Neuroradiology (2013) 55 (Suppl 1):S15–S159 DOI 10.1007/s00234-013-1236-8

Scientific Program (updated to August 9, 2013) 21st Advanced Course in Diagnostic Neuroradiology “Beyond morphology: advanced imaging modalities” 5th Advanced Course in Interventional Neuroradiology “Chronic ischemia of the brain and revascularization” Saturday, September 28, 2013 08:45–10:15

DIAGNOSTIC – Trauma Chair: F.E. Zanella (Germany)

ROOM HZ 2

Traumatic brain injury P.M. Parizel (Belgium) Trauma from the perspective of the neurosurgeon C. Renner (Germany) MRI of spinal injury J. Van Goethem (Belgium) 08:45–10:00

INTERVENTIONAL - Anatomical and pathophysiological basics Chair: M. Knauth (Germany)

ROOM HZ 4

Delayed and chronic ischemia of the brain – an underestimated feature? M. Söderman (Sweden) Vascular borderzones, microcirculation and collateral supply A. Valavanis (Switzerland) Basics of cerebral hemodynamics and metabolism in acute and chronic ischemia J. Sobesky (Germany) 10:00 – 10:45

Coffee break

10:45–12:15

DIAGNOSTIC - Brain tumors: new biological MR-techniques Chair: H. Lanfermann (Germany)

ROOM HZ 2

Requests from neurooncologist J. Steinbach (Germany) Susceptibility weighted techniques R. Gasparotti (Italy) MR derived biomarkers for quantification of microvascular disease in the ageing brain and neurodegenerative disorders A. Jackson (United Kingdom) Diffusion techniques P.M. Parizel (Belgium) 10:30–12:15

INTERVENTIONAL - Clinical findings and imaging of chronic ischemia Chair: B. Yan (Australia) Clinical and neuropsychological findings in patients with hemodynamic ischemia H. Steinmetz (Germany) Imaging patterns of ischemic lesions and differential diagnosis B. Schuknecht (Switzerland) Advanced imaging techniques in chronic hypoperfusion of the brain M. Wagner (Germany) Challenges of brain perfusion measurement M. Wintermark (USA) Discussion

ROOM HZ 4

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Neuroradiology (2013) 55 (Suppl 1):S15–S159

12:15 – 14:00

Lunch

14:00–15:20

DIAGNOSTIC – Neuroinflammation Chair: P. Lachezar (Bulgaria)

ROOM HZ 2

MR imaging in non-MS inflammation: immune-mediated diseases T. Yousry (United Kingdom) MR imaging in non-MS neuroinflammation: granulomatous disease F. Bonneville (France) MR imaging: neuroinflammation in immunocompromised patients A. Rovira (Spain) Discussion 14:00–15:20

INTERVENTIONAL - Treatment strategies in the light of recent randomized trials Chair: G. Schroth (Switzerland)

ROOM HZ 4

Revascularization in hemodynamic ischemia: which evidence do we have? L.J. Kappelle (The Netherlands) Medical therapy of patients with hemodynamic impairment. Can the brain survive without vessels? B. Yan (Australia) Neurointerventional revascularization techniques J. Gralla (Switzerland) EC-IC-Bypass in ischemic patients? P. Vajkoczy (Germany) 15:20 – 15:50

Coffee break

15:50–16:30

DIAGNOSTIC - Pain and epilepsy: can we imagine it? Chair: G. Krumina (Latvia)

ROOM HZ 2

Imaging pain H. Boecker (Germany) MRI in focal, non-lesional epilepsy S. Knake (Germany) 16:30–17:45

DIAGNOSTIC - Neurodegeneration: MR-modalities against biomarkers Chair: R. Vanninen (Finland)

ROOM HZ 2

Neurodegeneration: inflammatory reaction or vascular disorder M. Heneka (Germany) Imaging in Parkinson and other extrapyramidal disorders T. Stošic-Opincal (Serbia) Case presentation and discussion TBD 15:50–17:30

INTERVENTIONAL - Update on carotid and intracranial stenting after the RCTs Chair: J. Trenkler (Austria)

ROOM HZ 4

Carotid stenting in neuroradiology today: standard or niche indication? O. Jansen (Germany) Stenting of intracranial stenoses after SAMMPRIS C. Cognard (France) Periinterventional stroke, hemorrhage and hyperperfusion: how to avoid and manage complications during and after revascularisation I. Szikora (Hungary) How dangerous is revascularization? Cases and complications session D. Rüfenacht (Switzerland)

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S17

37th ESNR Annual Meeting Sunday, September 29, 2013 08:00–09:00

REFRESHER DIAGNOSTIC - Pediatric imaging Chair: P. Due-Tønnessen (Norway)

ROOM HZ 2

Differential diagnosis of pediatric brain tumors L. Porto (Germany) Real time MR technique for fetuses and neonates T. Feygin (USA) 08:00–09:00

REFRESHER INTERVENTIONAL - Intracranial aneurysms Chair: J. Ruscalleda Nadal (Spain), M. Söderman (Sweden)

ROOM HZ 3

Coiling vs. clipping in ruptured and unruptured aneurysms: long-term-efficacy and status of the debate A. Molyneux (United Kingdom) How to coil an aneurysm. Individual skill or reliable standards? L. Pierot (France) 09:00–10:00

Brain tumors Chair: P.M. Parizel (Belgium), M. Buruian (Romania)

ROOM HZ 2

Lymphomatoid spectrum disorders, Update 2013 A. Osborn (USA) Advanced tumor MRI M. Essig (Germany) 10:00 – 10:30

Coffee break

10:30–11:30

DIAGNOSTIC SPECIAL FOCUS - Spinal Imaging Chair: F. E. Zanella (Germany)

ROOM HZ 2

Advanced techniques for spine and spinal cord imaging T. Krings (Canada) High field strength at the spine, really a step forward? U. Attenberger (Germany) Differential diagnosis of acute myelopathy M. Thurnher (Austria) 10:30–11:30

INTERVENTIONAL SPECIAL FOCUS - Interventional stroke treatment Chair: R. von Kummer (Germany)

ROOM HZ 3

Randomized trials ahed: predictors for successful interventional stroke treatment R. Wiest (Switzerland) CT or MRI? Imaging for proper patient selection A. Dörfler (Germany) Materials, technical standards and procedural safety G. Schroth (Switzerland) 11:30 – 12:30

OPENING CEREMONY

12:30 – 14:00

Lunch/Lunch Symposium

14:00–15:30

ESNR Awards Ceremony

ROOM HZ 2

14:00–15:30

Parallel scientific session with introductory invited presentation Interventional aneurysms: new implants Chair: L. Pierot (France), C. Cognard (France)

ROOM HZ 5

New implants for aneurysm treatment S. Cekirge (Turkey)

ROOM HZ 2

S18

14:00–15:30

Neuroradiology (2013) 55 (Suppl 1):S15–S159

Parallel scientific session with introductory invited presentation Interventional stroke and revascularization Chair: I. Szikora (Hungary)

ROOM HZ 4

New devices and techniques O. Jansen (Germany) 14:00–15:40

Parallel scientific session Stroke diagnostic Chair: R. Wiest (Switzerland), M. Wagner (Germany)

15:30 – 16:00

Coffee break

16:00–18:00

Parallel scientific session with introductory invited presentation Diagnostic advanced MRI-techniques Chair: E. Hattingen (Germany), I. Pronin (Russia)

ROOM HZ 3

ROOM HZ 2

Diagnostic advanced MRI-techniques R. Deichmann (Germany) 16:00–18:00

Parallel scientific session with introductory invited presentation White Matter Diseases Chair: L. Markovic (Denmark)

ROOM HZ 3

Diagnostic white matter diseases: how to approach? F. Bonneville (France) 16:00–18:00

Parallel scientific session with introductory invited presentation Interventional AVM and AVF Chair: C. Stapf (France), J. Gralla (Switzerland)

ROOM HZ 5

Onyx in AVM and AVF: real complication rate L. Spelle (France) 16:00–18:00

Parallel scientific session with introductory invited presentation Spinal Imaging Chair: L. Weise (Germany), M. Muto (Italy) DTI of the spinal cord (technique and clinical applications) M. Sasiadek (Poland)

ROOM HZ 4

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Monday, September 30, 2013 08:00–09:00

Dementias beyond Alzheimer and psychiatric disorders Chair: N. Sadeghi (Belgium)

ROOM HZ 2

Dementias beyond Alzheimer P. Scheltens (The Netherlands) Advanced imaging in psychosis TBD Advanced imaging in vertigo Z. Merhemic (Bosnia and Herzegovina) 08:00–09:00

SAH and vasospasm Chair: V. Seifert (Germany)

ROOM HZ 3

Imaging assessment of patients with cerebral vasospasm after SAH J. Byrne (United Kingdom) Vasospasm: clinical concepts, therapeutic options and evidence H. Vatter (Germany) Interventional treatment of vasospasm: indication and how to do it J. Berkefeld (Germany) 09:00–10:00

Future MRI Chair: R. Deichmann (Germany)

ROOM HZ 2

Possibilities and limitations of functional MRI R. Göbel (The Netherlands) Clinical application ahead: quantitative imaging and multinuclear spectroscopy E. Hattingen (Germany) Real-time MRI: recent advances and future potential J. Frahm (Germany) 09:00–10:00

Parallel scientific interventional session Stroke aneurysm/AVM Chair: M. Khanghure (Australia), J. Byrne (United Kingdom)

10:00–10:30

Coffee break

10:30–11:30

DIAGNOSTIC SPECIAL FOCUS - Inflammatory disease Chair: G. Wilms (Belgium)

ROOM HZ 3

ROOM HZ 2

MRI in the diagnosis of MS: challenges and new evidences A. Rovira (Spain) Congenital infections A. Rossi (Italy) Imaging of vasculitis P. Sundgren (Sweden) 10:30–11:30

INTERVENTIONAL SPECIAL FOCUS - Clinical outcome after interventional procedures Chair: D. Rüfenacht (Switzerland)

ROOM HZ 3

New and rare techniques for aneurysm treatment: how to manage the risk of complications I. Saatci (Turkey) Aneurysms and AV-fistulae with cranial nerve deficits C. Cognard (France) Incidental aneurysms and vascular malformations C. Stapf (France) 11:30–13:00

Neuroradiology: from the past to the future. Dedicated to Hans Hacker Chair: F.E. Zanella (Germany) Neuroanatomy and high-resolution MRI R. Göbel (The Netherlands) Imaging in neuroscience W. Singer (Germany) Perspectives for neuroradiologists M. Leonardi (Italy)

ROOM HZ 2

S20 11:30–13:00

11:30–13:00

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Parallel scientific session Brain tumors 1 Chair: R. Colen (USA)

ROOM HZ 3

Parallel scientific session Pediatrics Chair: A. Rossi (Italy)

ROOM HZ 4

13:00–14:00

Lunch/Lunch Symposia

14:00–15:00

ESNR General Assembly

ROOM HZ 2

15:00–16:30

Paediatrics - Joint Session with the ASPNR Monothematic mini-course: “Advances in the understanding of brain malformations” Chair: A. Rossi (Italy), D. Shaw (USA)

ROOM HZ 4

Antenatal MRI: pushing the edge for early recognition A. Righini (Italy) DTI for brain malformations: does it help? T.A. Huisman (USA) Genetic/neuroradiological correlations in 2013 N. Girard (France) Hindbrain / midbrain malformations: the new classification A.J. Barkovich (USA) Discussion 15:00–16:30

Parallel scientific session with introductory invited presentation Spine Chair: M. Muto ( Italy), J. Walecki (Poland)

ROOM HZ 5

MRI of peripheral nerves and plexuses: imaging techniques and key findings M. Pham (Germany) Interventional spine: percutanous treatment of disc and bone M. Muto (Italy) 15:00–16:30

Parallel scientific session with introductory invited presentation Head and neck Chair: M. Mack (Germany), S. Kösling (Germany)

ROOM HZ 6

Diagnostic head and neck: vascular lesions temporal bone S. Kösling (Germany) 15:00–16:30

15:00–18:00

Parallel scientific session Brain Tumors 2 Chair: P. Sundgren (Sweden)

ROOM HZ 3

ESNR Interventional Hot Topics Chair: H. Brückmann (Germany) First results of ARUBA: end of invasive AVM-treatment? Neurological perspective C. Stapf (France) Lessons to learn from ARUBA: consequences for interventional treatment? R. Chapot (Germany) Discussion Interventional stroke treatment: are we the good guys? R. von Kummer (Germany) Interventional stroke treatment: perspectives for better study results J. Gralla (Switzerland) Discussion Clipping vs. coiling still a matter of debate? Neurosurgical perspective V. Seifert (Germany) Coiling after ISAT: a single lucky study or basis for reliable clinical application? A. Molyneux (United Kingdom) Discussion New materials and perspectives for interventional aneurysm treatment I. Szikora (Hungary) Do we need better rules for device approval in Europe? E. Houdart (France) Discussion

ROOM HZ 2

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S21

16:30–17:00

Coffee break

17:00–18:30

Parallel scientific session Advanced imaging epilepsy and consciousness Chair: P. Barsi (Hungary)

ROOM HZ 6

Parallel scientific session Free topics Chair: J. Wilmink (The Netherlands)

ROOM HZ 5

Parallel scientific session Stroke recanalization Chair: I. Saatci (Turkey)

ROOM HZ 3

Parallel scientific session Inflammatory disease Chair: T. Ogawa (Japan)

ROOM HZ 4

17:00–18:30

17:00–18:30

17:00–18:30

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Tuesday, October 1, 2013 08:00–09:00

REFRESHER COURSE DIAGNOSTIC - Epilepsy, head and neck Chair: T. Tali (Turkey)

ROOM HZ 2

Tumors in epilepsy A. Osborn (USA) Cranial nerve palsies in head and neck diseases M. Mack (Germany) 08:00–09:00

SPECIAL FOCUS INTERVENTIONAL – Advanced angiographic imaging and radiation protection Chair: J. Berkefeld (Germany)

ROOM HZ 3

Beyond fluoroscopy and DSA: indications for new neuroangiographic features A. Dörfler (Germany) Radiation dose in interventional neuroradiology M. Söderman (Sweden) Radiation protection in interventional neuroradiology R. Anxionnat (France) 09:00–10:00

Paediatric Chair: C. Hoffman (Israel)

ROOM HZ 2

Diagnostic pediatrics: epilepsy in malformations of the cerebral cortex N. Colombo (Italy) Uncommon pediatric tumors M. Warmuth-Metz (Germany) 09:00–10:00

Imaging in psychiatry Chair: G. Wilms (Belgium)

ROOM HZ 3

Clinical signs and biological markers in the prediction of Alzheimer's disease F. Jessen (Germany) 10:00–10:30

Coffee break

10:30–12:00

ESNR - ASNR joint session Chair: T. Tali (Turkey)

ROOM HZ 2

Advanced imaging of brain tumors with a focus on molecular characterization R. Colen (USA) MEG and MRI of the cognitive consequences of traumatic brain injury R. Lee (USA) Advanced imaging of stroke G. Zaharchuk (USA) 10:30–12:00

12:00–13:00

Parallel scientific session Advanced imaging: future tecniques in neuroradiology Chair: R. Siemund (Sweden) Closing ceremony

ROOM HZ 3

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Scientific paper sessions (original and unedited texts, authors and affiliations as received by the authors)

SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 5 14:00–15:30 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - INTERVENTIONAL ANEURYSMS: NEW IMPLANTS S.15.01 STENT-ASSISTED COIL EMBOLIZATION WITH A CLOSED CELL STENT DEVICE C. Taschner1, W. Reith2, J. Gralla3, R. Du Mesnil De Rochemont4, O. Singer4, C. Hader1, S. Meckel1, P. Papanagiotou2, C. Roth2, H. Körner2, E. Dabew2, U. Yilmat2, S. Zubler3, G. Schroth3, M. Schumacher1, J. Berkefeld4 1

Dept. of Neuroradiology, University Hospital Freiburg, Freiburg, Germany, 2Dept. of Neuroradiology, University Hospital Homburg/Saar, Homburg, Germany, 3Dept. of Neuroradiology, University Hospital Bern, Bern, Switzerland, 4Dept. of Neuroradiology, University Hospital Frankfurt, Frankfurt, Germany OBJECTIVE To evaluate safety and efficacy of a novel closed cell stent system (Neuroclosed, Acandis, Pforzheim, Germany) for the treatment of wide-necked intracranial aneurysms by stent-assisted coil embolization. METHODS Prospectively maintained database including 14 patients (age range 39– 71 years; mean age, 56,5 years) treated in three different centres for incidental aneurysms ( Internal carotid artery, n=10; basilar trunk, n=3; middle cerebral artery, n=1). We assessed the patient clinical history, aneurysm shape and dimensions, technical details and complications of the procedures, degree of aneurysm occlusion, and clinical findings upon discharge. In addition angiographic results and adverse neurological events during the 6 month follow-up period were recorded. Angiographic data was reviewed by an independent core lab. RESULTS Positioning of the Neuroclosed stent was successful in all cases. In 2 cases stents migrated after positioning. Thrombo-embolic complications occurred in one case, leading to a transient neurological deficit. At 6 months followup all patients had a mRs of 0. Angiograms obtained immediately after the procedure showed complete occlusion of the aneurysmal sac in 6 of 14 patients (43 %), a minor neck remnant in 2 (14 %), and a moderate excentric remnant in 6 (43 %). Upon follow-up angiography complete occlusion of the aneurysmal sac was present in 6 of 13 patients (46 %), a minor neck remnant in 1 (8 %), and a moderate excentric remnant 6 (46 %). One patient had a re-embolisation after the 6 months follow-up angiogramm. CONCLUSION Our data suggests that the Neuroclosed stent can safely be used for stent-assisted coil embolisation of incidental intracranial aneurysms. Keywords Aneurysm, stent assisted coiling

S.15.02 FLOW DIVERTER STENTS IN BIFURCATION ANEURYSMS S. Saleme, J.A. Mejia Nunez, S. Ponomarjova, D. Ayoub, T. Dinh, C. Mounayer CHU de Limoges- Department of Neuroradiology, Limoges, France PURPOSE We report our experience with Flow Diverters (FD) in the treatment of aneurysms in artery bifurcations beyond the level of the circle of Willis. MATERIAL AND METHODS A total of 37 bifurcation aneurysms were treated with FD, 43,2 % (16/37) at the middle cerebral artery bifurcation, 32,4 % (12/37) at the anterior communicating complex, 18,9 % (7/37) at the internal carotid bifurcation and 8,1 % (3/37) at the pericallosal artery. Thirty-eight flow diverter stents were deployed (1,03 FD/aneurysm). Aneurysm sizes varied from 1 mm to 20 mm (6 mm average). Eleven out of thirty-seven aneurysms (29,7 %) have been previously treated by coiling or stent+coiling. All patients but four (33/37, 89,2 %) had MRI 24–48 hs after the procedure. MRI at 6months was performed in 17/37 (45,9 %) patients. Control angiography at 6-months was obtained in 29/37 (78,4 %). RESULTS Thirty-seven aneurysms were treated flow diverters in artery bifurcations (31/37, 83,8 % saccular; 6/37, 16,2 % blister-like). There were no failure of stent deployment but in 1 case (2,7 %) balloon angioplasty was necessary for the perfect opening of the stent. Reversible neurological complications were noted in 8,1 % (3/37), and permanent neurological complications in 8,1 % (3/37). There was no mortality. MRI at 24-48hs showed micro embolic spots at Diffusion in 21,6 % (8/37), all asymptomatic, and ischemic lesions in the territory of the shunted branch in 18,9 % (7/37), 4 of which with reversible symptoms. MRI at 6-months showed no new ischemic lesion in 94,1 % (16/17) and a junctional infarct (5,9 %, 1/17) responsible for a transient facial paralysis due to occlusion of the MCA frontal branch covered by a FD , probably in relation to flow competition. Control angiography at 6-months showed complete occlusion of the aneurysm in 96,5 %(28/29) and residual sac in 3,5 %(1/29). CONCLUSION Aneurysms in artery bifurcations beyond the level of the circle of Willis are amenable to treatment by flow diverters in selective cases. Keywords Aneurysm, flow diverter stents, endovascular

S.15.03 INTENSIFYING PLATELET INHIBITION IN POOR RESPONDERS TO CLOPIDOGREL ACCORDING TO THE MULTIPLATE® ANALYZER DURING INTRACRANIAL FLOW-DIVERTING STENT IMPLANTATION I. Oran1, C. Cinar1, H. Bozkaya1, M. Korkmaz2

S24 1 Ege University Medical School Department of Radiology, Izmir, Turkey, 2Dumlupinar University Medical School Department of Radiology, Kutahya, Turkey

PURPOSE This study aims to identify the role of platelet function test Multiplate® Analyzer in optimizing platelet inhibition in case of poor response to clopidogrel during intracranial flow-diverting stent implantation. METHODS We recorded patient and aneurysm characteristics, initial antiplatelet drugs, pre-, intra-, post-procedure AUC value with Multiplate® Analyzer, technical variables, changes in antiplatelet regime, and perioperative thromboembolic and hemorrhagic complications up to day-30 after intracranial flow-diverting stent implantation at our institution during a 24-month period. All patients were loaded classically with 600 mg clopidogrel+300 mg aspirin 8–12 hours before the intervention. Initial measurement was obtained immediately before the procedure. The test was repeated when additional IV and PO antiplatelet loading was administered, after 30-min and minimum 4-hour respectively. RESULTS Sixty patients underwent 64 procedures accompanied by 76 time antiplatelet loading during the study period. Preoperative initial test results for clopidogrel accepted as sufficient (below the upper level of therapeutic window-467AUC) in 46 of 60 patients, while the remaining 14 (23.3 %) were defined as poor responders to clopidogrel. According to the initial test results, 15 of 64 (23.4 %) procedures were changed; 12 (18.7 %) changes in loading strategy, 2 postponing of procedure, and 1 change in embolization technique. All these procedural changes resulted in reduction of mean ADP value from 795AUC (initial, n=14) to 279AUC (tirofiban IV, n=9) at 30min and 301AUC (tirofiban IV+ticlopidine PO, n=11) at 4-hour. There were 3 fatal perioperative complication (5 %); one brainstem ischemia due to technical complication (insufficient stent expansion), and two fatal intracranial hemorrhage 1- and 18-day after the intervention. None of the patient having complication was in the group of modified loading. No thromboembolic events occurred in the cohort. CONCLUSION Intensifying platelet inhibition in poor responders to clopidogrel was effective to reduce thromboembolic complication during flow-diverting stent treatment of intracranial aneurysm. The Multiplate® Analyzer was useful to monitor closely platelet function either following initial loading before the intervention or after each extra loading during/following the procedure. Keywords aneurysm, flow-diverting stent, platelet function S.15.04 REMOSTENTING TECHNIQUE: COMBINED USE OF DOUBLE LUMEN REMODELLING BALLOONS WITH LOW PROFILE STENTS: LVIS JR, LEO BABY AND ACCLINO K. Kadziolka, L. Estrade, L. Pierot CHU Reims, Interventional Neuroradiology Department, Reims, France PURPOSE Remodeling technique and stenting represents an important options for intracranial aneurysm endovascular treatment. The newly designed available double lumen balloons and low profile stents offer possibility of combined approach with straightforward and safer strategy. OBJECTIVE To present the initial experience and feasibility of using new double lumen remodeling balloons Scepter and Ascent together with three types of low profile stents: braided Lvis Jr and Leo Baby as well as closed cell stent Acclino. All 20 stents were deployed through the balloon internal lumen without the need for any supplementary manoeuvres or stents dedicated microcatheter.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS 19 patients with 20 aneurysms were referred for endovascular treatment with remostenting technique. RESULTS All aneurysms were coiled but risk of coil protrusion or important anatomical modification was anticipated based on images with and without balloon inflated. In this situation we were able to use balloon microcatheter for stent delivery. Two periprocedural technical complications were noted and resolved without clinical sequelae. In one case postprocedural instent thrombosis was diagnosed and immediately treated with mild clinical modification of patient outcome. No mortality were observed. We report as well some technical considerations regarding three types of stents. CONCLUSIONS Stent plays important role as coils or endothelium scaffolding , provides flow diversion as well as confirm and stabilize anatomical modification due to the remodelling balloon microcatheter presence in parent artery. Association of new double lumen ballons Scepter and Ascent with low profile stents Lvis Jr, Leo baby and Acclino during balloon assisted technique provide additional security for instable and protruding coils cage at the end of remodelling. Remostenting reduces periprocedural risk of multiple manoeuvres needed for classical remodelling than stenting technique. Due to different types of low profile stents available that technique can be applied for proximal and distal intracranial aneurismal localisation. Keywords Stenting, remodeling, aneurysms S.15.05 PIPELINE FLOW DIVERTING STENTS REDUCE ANEURYSM INFLOW WITHOUT RELEVANTLY AFFECTING STATIC INTRA-ANEURYSMAL PRESSURE M. Brockmann1, H.U. Kerl2, H. Boll2, T. Fiebig2, G. Figueiredo2, A. Förster2, I.S. Nölte2, C. Groden2 1

University Hospital of the RWTH Aachen, Department of Diagnostic and Interventional Neuroradiology, Aachen, Germany, 2University Medical Center Mannheim, Department of Neuroradiology, Mannheim, Germany PURPOSE Flow diverting stent (FDS) implantation is an endovascular treatment option for intracranial aneurysms. However, little is known about the hemodynamic effects, and an increase of intra-aneurysmal pressure after successful implantation of FDS has been discussed to be related to delayed rupture of FDS treated aneurysms. The objectives of this study were to a.) assess the effect of stent compression on FDS porosity; b.) evaluate the influence of single and overlapping implantation of FDS on intra-aneurysmal flow profiles; and, c.) correlate stent porosity with changes of static mean intra-aneurysmal pressure. METHODS Intra-aneurysmal time-density curves were recorded at 15 fps in a pulsatile in vitro flow model before and after implantation of FDS (Pipeline Embolization Device; ev3) in four different types of aneurysm models. The reduction of the maximum contrast inflow and the time to maximum intra-aneurysmal contrast were calculated. Micro-CT was performed after implantation of each stent and compression-related FDS-porosity was measured. The influence of FDS placement on mean static intra-aneurysmal pressure was measured. RESULTS FDS compression resulted in an almost linear reduction of the stents porosity. Stent porosity (struts/mm) correlated significantly with the reduction of aneurysm contrast inflow (R2=0.81, p<0.001) and delay until maximum contrast (R2=0.34, p=0.001). Circulating intra-aneurysmal high-velocity flow was terminated in all sidewall models after implantation of a single stent.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Superimposition of two stents reduced maximum intra-aneurysmal contrast by 69.1±3.1 % (mean±1SD). Intra-aneurysmal mean static pressure did not correlate with FDS porosity or number of implanted stents. CONCLUSIONS Implantation of FDS effectively reduces aneurysm inflow in a porositydependent way, without relevantly affecting static mean intra-aenurysmal pressure. Keywords aneurysm, flow diverter stent, hemodynamics S.15.06 COST EFFICIENCY AND FOLLOW-UP DATA USING THE PENUMBRA COIL 400 COMPARED TO ORBIT/GALAXY FOR TREATMENT OFANEURYSMS IN THE CEREBROVASCULAR SYSTEM J. Milburn1, A.L. Pansara1, R.C. Martinez2, G. Vidal3 1

Ochsner Medical Center, Department of Radiology, New Orleans, LA, USA, 2Louisiana State University, Department of Neurology, New Orleans, LA, USA, 3Ochsner Medical Center, Department of Neurology, New Orleans, LA, USA PURPOSE This study was designed to compare the cost effectiveness and treatment stability of the larger diameter Penumbra Coil 400 with the commonly used smaller diameter Orbit/Galaxy coil. METHODS In a retrospective single center study, 18 consecutive aneurysms treated using the Penumbra coil were compared to 40 treated with Orbit or Galaxy coils from 2010 to February 2012. Measurements included aneurysm volumes, number of coils used, total length of coil, and final packing density. Cost analysis was performed using the retail coil prices based on the measurements in this study. Aneurysm occlusion class based on the Raymond Scale at the time of initial treatment was compared with follow-up studies to evaluate coil stability. RESULTS Number of coils per aneurysm volume was 0.026 coil/mm3 for Penumbra. This was significantly less than 0.114 coil/mm3 for Orbit/Galaxy. Average packing density of 33.7 % for Penumbra was significantly greater than 24.4 % for Orbit/Galaxy. Aneurysm occlusion rates at the time of treatment were similar in the 2 groups. Cost analysis estimated a 67 % reduced cost for Penumbra coils per volume of aneurysm. Follow-up was available on 14 of the 18 Penumbra aneurysms with an average time of 9.6months, and stability or improved obliteration was noted in 13. There was one coil migration into mural thrombus which was retreated with additional coiling. Follow-up studies on 25 of the 40 aneurysms treated with Orbit/Galaxy averaging 11.4 months showed stability or improvement in 21. There were 4 that had a worse Raymond class, and one was retreated with stent-coiling. CONCLUSIONS Aneurysm treatment using the Penumbra Coil 400 resulted in higher packing density compared to Orbit/Galaxy. The Penumbra coil was more cost effective, and follow-up studies suggested durable occlusions. Keywords Aneurysm, coiling, interventional

S25 SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 4 14:00–15:30 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - INTERVENTIONAL STROKE AND REVASCULARIZATION S.16.01 INITIAL CLINICAL EXPERIENCE WITH THE ADAPT TECHNIQUE: A DIRECTASPIRATION FIRST PASS TECHNIQUE FOR STROKE THROMBECTOMY D. Frei1, A.S. Turk2, A. Spiotta3, J. Mocco4, B. Baxter5, D. Fiorella6, A. Siddiqui7, M. Mokin7, M. Dewan4, H. Woo6, R. Turne 3, H. Hawk2, A. Miranpuri2, I. Chaudry2 1

Swedish Medical Centre, Department of Radiology, Englewood, CO, USA, 2Medical University of South Carolina, Department of Radiology, Charleston, SC, USA, 3Medical University of South Carolina, Department of Neurosciences, Charleston, SC, USA, 4University of Vanderbilt, Department of Radiology and Radiological Sciences, Nashville, TN, USA, 5Erlanger Health System, Department of Radiology, Chattanooga, TN, USA, 6Stony Brook University, Department of Neurosurgery, Stony Brook, NY, USA, 7University at Buffalo, Department of Neurosurgery, Buffalo, NY, USA PURPOSE The development of new revascularization devices has improved recanalization rates and time but not clinical outcomes. We report our initial results with a new technique utilizing a direct aspiration first pass technique with a large bore aspiration catheter as the primary method for vessel recanalization. METHODS A retrospective evaluation of a prospectively captured database of 37 patients at six institutions was performed on patients where the ADAPT technique was utilized. The data represent the initial experience with this technique. RESULTS The ADAPT technique alone was successful in 28 of 37 (75 %) cases although six cases had large downstream emboli that required additional aspiration. Nine cases required the additional use of a stent retriever and one case required the addition of a Penumbra aspiration separator to achieve recanalization. The average time from groin puncture to at least Thrombolysis in Cerebral Ischemia (TICI) 2b recanalization was 28.1 min, and all cases were successfully revascularized. TICI 3 recanalization was achieved 65 % of the time. On average, patients presented with an admitting National Institutes of Health Stroke Scale (NIHSS) score of 16.3 and improved to an NIHSS score of 4.2 by the time of hospital discharge. There was one procedural complication. CONCLUSIONS This initial experience highlights the fact that the importance of the technique with which new stroke thrombectomy devices are used may be as crucial as the device itself. The ADAPT technique is a simple and effective approach to acute ischemic stroke thrombectomy. Utilizing the latest generation of large bore aspiration catheters in this fashion has allowed us to achieve excellent clinical and angiographic outcomes. Keywords Acute ischemic stroke, mechanical thrombectomy, clinical outcome

S26 S.16.02 SOLVING THE ISSUE OF RESTENOSIS AFTER STENTING OF INTRACRANIAL STENOSES: EXPERIENCE WITH TWO THIN STRUT DRUG ELUTING STENTS (DES) - TAXUS ELEMENT™ (BOSTON SCIENTIFIC) AND RESOLUTE INTEGRITY™ (MEDTRONIC INC.) W. Kurre1, M. Aguilar-Pérez1, S. Fischer1, G. Arnold2, E. Schmid3, H. Bäzner3, H. Henkes1 1

Klinikum Stuttgart, Department of Neuroradiology, Stuttgart, Germany, Klinikum Sindelfingen, Department of Neurology, Sindelfingen, Germany, 3 Klinikum Stuttgart, Department of Neurology, Stuttgart, Germany 2

BACKGROUND Up to 30 % of patients treated with bare-metal stents for intracranial atherosclerotic lesions develop restenoses. DES significantly reduced recurrences after coronary artery angioplasty but the higher rigidity compared to bare-metal devices limited their application in neurovascular procedures. New generation thin-strut DES are more suitable for cerebrovascular interventions and may achieve improvement in terms of restenosis. The purpose of this study was to report our experience with thinstrut DES for the treatment of intracranial atherosclerotic disease. METHODS We retrospectively reviewed consecutive patients treated for an intracranial atherosclerotic stenosis with Taxus Element™ or Resolute Integrity™ between March 2011 and December 2012. Technical success was defined as the ability to deploy the device at the desired location and reduce the degree of stenosis below 50 %. Procedure related ischemic or haemorrhagic strokes with neurological symptoms lasting for more than 24 hours were reported. All patients were scheduled for regular control angiography after 6 weeks, 3, 6 and 12 month and yearly thereafter. Any new luminal narrowing more than 50 % was regarded as a restenosis. RESULTS In the defined period we treated 86 patients with 99 intracranial stenoses (including 15 recurrences after stenting). Taxus Element™ was used in 80 and Resolute Integrity™ in 19 targets. Locations were as follows: petrous internal carotid artery (ICA) (n=7), cavernous ICA (n=16), intradural ICA (n=8), middle cerebral artery (n=15), V3/V4 segments of the vertebral artery (n=41) and basilar artery (n=12). 74 of 84 (88.1 %) de novo lesions were treated successfully, 8 (9.5 %) were inaccessible and 2 (2.3 %) residual stenoses remained. Of 15 restenoses 9 (60 %) were treated successfully, 5 (33.3 %) were inaccessible and one (6.7 %) residual stenosis remained. Periprocedural strokes occurred in 8 (9.3 %) patients. Follow up angiography was available for 69 of 83 (83.1 %) successfully treated lesions after an average of 248 days (range 42–720). One asymptomatic vessel occlusion occurred and one patient developed a moderate restenosis (2.4 %). One ipsilateral stroke was associated with early cessation of clopidogrel. CONCLUSION DES substantially reduced the rate of restenosis compared to reported data on bare-metal stents. Technical feasibility was similar to bare-metal balloon-expandable devices. Procedure related neurological complications occurred within the expected range. Keywords Intracranial atherosclerosis, drug eluting stent, restenosis

Neuroradiology (2013) 55 (Suppl 1):S15–S159 1

Universitätsklinikum Dresden, Abteilung Neuroradiologie, Dresden, Germany, 2Vanderbilt University, Department of Neurological Surgery, Nashville, TN, USA, 3University of Cincinnati, Department of Neurology, Cincinnati, OH, USA, 4Medical College of Wisconsin, Department of Neurology, Neurosurgery & Radiology, Milwaukee, WI, USA, 5Grady Memorial Hospital, Department of Neurology, Neurosurgery and Radiology, Atlanta, GA, USA PURPOSE Recanalization with standard lytic therapy has been reported to have a greater likelihood to occur when clot length is less than 8 mm. Thinsliced non-enhanced CT (NCCT) images (2.5 mm or less) may be used to evaluate clot lengths in large artery occlusions. The goal of the THERAPY Trial is to examine safety and effectiveness of the Penumbra System® as adjunctive treatment to IV rtPA in stroke patients with large vessel occlusions and an extensive clot burden. METHODS THERAPY is a prospective, randomized, multicenter, concurrent controlled study. Up to 692 patients from 18 to 85 years presenting with acute ischemic stroke symptoms, an NIHSS score of at least 8 and eligible for IV rtPA with clot length of 8 mm or greater in the anterior circulation from reconstructed thin-sliced NCCT are randomized one to one to combined approach with the Penumbra System or IV rtPA therapy alone. The primary endpoints are good functional outcome at 90 days and incidence of serious adverse events. Secondary endpoints include good functional and neurological outcomes at discharge and at 30 days and the incidence of intracerebral hemorrhage. An independent Core Laboratory evaluates imaging data, while a Clinical Events Committee/Data Safety Monitoring Board assesses safety. RESULTS Currently, close to 41 centers have received IRB approval, and 35 patients are randomized. A preliminary analysis of the reasons for screened failures in patients eligible for IV rtPA shows baseline NIHSS score and age over 85 are the top two criteria for exclusion. Reasons for being unable to obtain consent include shipping from an outside institution and/or outside the time window for consent (45 %), refused consent (9 %), no family member present to consent (6 %), and no reason provided by the site (40 %). Of those patients who had their clot measured at screening, about 75 % had clot lengths of at least 8 mm. CONCLUSIONS The THERAPY Trial may serve as a seminal study to define the role of thrombectomy with clinically used mechanical devices in a stroke cohort unlikely to respond well to IV rtPA. An examination of its unique selection criteria demonstrates trial feasibility, with few patients lost to the unique THERAPY imaging selection criterion. Keywords Acute ischemic stroke, clinical trial, mechanical thrombectomy S.16.04 MECHANICAL RECANALIZATION OF ACUTE M1 OCCLUSIONS WITH THE PRESET® STENTRETRIEVER IN 48 PATIENTS TECHNICAL SUCCESS AND CLINICAL OUTCOME S. Prothmann1, F. Kober1, S. Wunderlich2, J. Kleine1, K. Kreiser1, T. Boeckh-Behrens1, C. Zimmer1, H. Poppert2 1

Klinikum rechts der Isar, Department of Neuroradiology, Munich, Germany, Klinikum rechts der Isar, Department of Neurology, Munich, Germany

2

S.16.03 THERAPY: A PROSPECTIVE, RANDOMIZED, CONTROLLED TRIAL TO EVALUATE THE ROLE OF MECHANICAL THROMBECTOMY AS ADJUNCTIVE TREATMENT TO IV RTPA FOR ACUTE ISCHEMIC STROKE THERAPY R. von Kummer1, J. Gerber1, J. Mocco2, P. Khatri3, O. Zaidat4, R. Gupta5

PURPOSE The aim of this study was to analyze technical success, safety and clinical outcome of mechanical recanalization in acute M1 occlusions with the pREset® thrombectomy device. METHODS We conducted a retrospective, single-arm study of 48 consecutive patients (24 female, 73 y median age) presenting with an acute M1 occlusion.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 According to our institutional guidelines all patients received best medical treatment and a mechanical recanalization with the pREset® device (Phenox, Bochum, Germany) within 6 hours after symptom onset. We assessed recanalization rates (TICI), time parameters, clinical outcome (NIHSS, mRS), procedure-related complications and intracerebral hemorrhage. RESULTS 36 patients received i.v. rtPA before intra-arterial treatment. Overall we achieved a potentially beneficial TICI 2b/3 recanalization rate of 81,3 %. The median number of stentretriever passages was 2 (1–8). The median procedure time was 45 minutes (11–185). The median time from symptom onset to reperfusion was 285 minutes (118–568). The median NIHSS score at admission was 15 (1–27). 33 patients (69 %) had an early NIHSS improvement of at least 4 points. In average the NIHSS score improved by 7,5 points. The median post procedural NIHSS score was 6 (0–24). The mean mRS score at dismissal was 3. 17 patients (33 %) had a mRS score of 0–2. 3 patients (6 %) died during hospitalization. In 6 cases (12 %) procedure related complications could be noted: 2 thromboembolic events, 2 dissections and 2 subarachnoid hemorrhages. Hemorrhagic transformation of the infarcted area occurred in 13 cases (27 %): 4 could be identified as HI1, 8 as HI2 and 1 as PH1, according to the ECASS criteria. CONCLUSIONS Mechanical recanalization of acute M1 occlusions with the pREset® device provides a high recanalization rate with an acceptable low complication rate. Besides, a clear clinical improvement could be seen. However, the clinical benefit of mechanical recanalization needs to be evaluated in the upcoming randomized controlled trials. Keywords Mechanical recanalization,M1 occlusion, stentretriever S.16.05 MECHANICAL THROMBECTOMY WITH DOUBLE SOLITAIRE STENTS M. Stauder, M. Heddier, H. Nordmeyer, C.P. Stracke, R. Chapot Alfried-Krupp Hospital, Essen, Germany PURPOSE The Solitaire stent is a good working device for thrombectomy in intracranial vessels. In some cases it is not possible to catch the clot with one device. METHODS In 2012 we performed around 280 thrombectomies in Alfried-Krupp Hospital, Essen. In most of the cases the successful recanalization was realised by using one device. When the clot was positioned at carotid T, mediabifurcation or even in the posterior circulation, it was necessary to use two Solitaire stents at the same time for complete clot removel. CONCLUSION Our experience suggest that double solitaire manoveurs are an effective tool for endovascular treatment of acute stroke. The rate of recanalization can be rised. The risk of symptomatic or asymptomatic intracranial hemorrhage is not higher than by using a single device. Keywords Double solitaire, recanalization rate, stroke S.16.06 HIGH CLOT BURDEN IN ACUTE EMBOLIC STROKE IN THE ANTERIOR CIRCULATION: COMPARISON OF NEUROTHROMBECTOMY AND SYSTEMIC THROMBOLYSIS A. Rohr1, J. Meyne2, P. Zimmermann2, C. Riedel1, F. Papengut2, R. Stingele3, O. Jansen1, G. Deuschl2, A. Binder2 UKSH Institute of Neuroradiology, Kiel, Germany, 2UKSH Department of Neurology, Kiel, Germany, 3DRK Clinic Köpenick Department of Neurology, Berlin, Germany 1

S27 PURPOSE To evaluate the efficacy and safety of neurothrombectomy in the treatment of acute embolic stroke in patients selected by a thrombus length of >= 8 mm using the stent-retriever TREVO device. METHODS 40 patients (mean age 66.7±14 years; 27 females) with acute artery occlusion in the anterior circulation with a thrombus length of>= 8 mm as measured on non contrast-enhanced cranial CTs were treated with neurothrombectomy additionally to standard stroke treatment between January 2011 and March 2012 (mean NIHSS on admission 15.3). 25 patients were treated with mechanical thrombectomy alone, the remaining patients were treated with additional i.v.-thrombolysis (bridging concept). We compared the outcome to a historical group of 42 patients (mean age 71.5±11.6; 21 females) with a thrombus length of>= 8 mm that received systemic thrombolytic therapy only (mean duration of symptoms 74.3±27 minutes, mean NIHSS on admission 13.1). Clinical outcome (modified Rankin scale) was assessed on admission, at discharge and at day 90. RESULTS Thrombectomy group and control group data on admission did not differ except for time from symptom onset until time of admission (156.2 min vs. 74.4 min; p=0.001). The mean duration from admission to start of angiographic interventions (including time to establish general anaesthesia) was 75.8±37.1 minutes (range 29 to 189 minutes). Artery recanalization (Thrombolysis In Cerebral Infarction Score 2b or 3) was achieved in 33 patients (83 %). The mean time from symptom onset to recanalization was 319.9±99 minutes. Treatment-related complications occurred in 3 patients (8 %). Mean modified Rankin scale score on admission was 4.6 ± 0.6 (thrombectomy) vs. 4.38±0.8 (control), at discharge 3.00±1.8 vs. 4.7±1.3, (p<0.01) and at day 90 2.6±1.8 vs. 4.8±1.2 (p<0.01), respectively. On Day 90, 7 vs. 24 patients experienced no improvement on the modified Rankin scale. Symptomatic intracranial hemorrhage occurred in 3 vs. 7 patients, 3 vs. 17 patients died within 90 days (thrombectomy vs. control each). CONCLUSIONS This study in patients with high clot burden found that thrombectomy with the TREVO device has an acceptable risk and was superior to iv-thrombolysis alone. This suggests that stratifying treatment for clot length by 8 mm might be a powerful approach to improve the outcome of mechanical thrombectomy. Keywords Stroke, recanalization, thrombolysis SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 3 14:00–15:40 PARALLEL SCIENTIFIC SESSION - STROKE DIAGNOSTIC CO.01.01 NONINVASIVE EVALUATION OF CEREBRAL ARTERIOVENOUS MALFORMATIONS BY 4D-CT ANGIOGRAPHY USING 320DETECTOR ROW CT H. Tajiri, L. Jin, T. Tsukiyama, T. Okabe, H. Kamide, S. Sekine, T. Shimizu, T. Ohiwa Shonan Kamakura General Hospital, Kamakura, Japan BACKGROUND AND PURPOSE Patients with higher Spetzler-Martin grade cerebral arteriovenous malformations (AVMs) are associated with poorer neurologic and clinical outcomes. Four dimensional computed tomography angiography (4D-CTA) is newly and promising technique in the diagnosis of patients with cerebral arteriovenous malformations (AVMs). The purpose of this retrospective study was to investigate the utility of 4D-CTA using whole-brain 320-detector row CT for assessing cerebral AVMs compared with conventional angiography (CA).

S28 MATERIALS & METHODS Participants comprised patients admitted to our institution from November 2010 to March 2013 due to cerebral AVMs, who underwent both 4D-CTA and CAwithin 14 days. The diagnosis of AVM was finally confirmed by CA. Two readers reviewed 4D-CTA and CA under consensus regarding detection rate of the AVMs, each component of the AVMs (feeders, nidi, drainers) which was scored using four-point grading scale (excellent=3, good=2, fair=1, poor=0), and the Spetzler-Martin (S-M) grade. RESULTS During study periods, fifteen patients met our criteria. In every case, cerebral AVM was diagnosed by 4D-CTA. The average score for feeders, nidi, and drainers was 2.0, 2.3, and 2.3 in 4D-CTA and 2.2, 2.5, and 2.5 in CA, respectively. The average score of S-M grade was both 2.5. There were no significant differences statistically between two modalities (P<.005). CONCLUSION 4D-CTA using 320-detector row CT is a very reliable method and offered diagnostic performance equivalent to CA in detecting and predicting S-M classification of cerebral AVMs. Keywords Arteriovenous malformation, 320-detector row CT, Spetzler-Martin grade CO.01.02 PERFUSION CT IN STROKE MIMICS N. Sarbu, O. Chirife, E. Ripoll, S. Capurro, A. López, D. Campodónico, J. Blasco, L. San Román, J. Macho, L. Oleaga Hospital Clinic of Barcelona, Barcelona, Spain PURPOSE To describe the findings on perfusion CT studies in patients with stroke mimics. MATERIAL AND METHODS All adult patients who presented between 2010–2012 at our stroke center were retrospectively identified. The standard imaging protocol for acute stroke during the analyzed period included: unenhanced cranial CT, whole-brain perfusion CT and CT angiography on a 128-slice Dual Source CT scanner. All patients with final diagnosis other than acute ischemic/ hemorrhagic stroke were considered stroke-mimics and were analyzed for abnormalities on perfusion CT. Perfusion maps were interpreted for mean transit time (MTT), cerebral blood flow (CBF) and cerebral blood volume (CBV). Hypoperfusion was defined as increased MTT, decreased CBF and normal/decreased CBV; hyperperfusion as decreased MTT, increased CBF and normal/increased CBV. We used a consensus reading of two radiologists, one from neuroradiology division. RESULTS A total of 882 patients suspected of stroke presented at our unit during 3 years; 93 of them had lesions masquerading as acute stroke and perfusion CT available. The main final diagnosis of the 93 patients was: seizure 22 patients (23,6 %), migraine 10 (10,7 %) and confusional states 10 (10,7 %). Perfusion CT was altered in 31 subjects (33,3 %). The principal final diagnosis of the 31 with perfusion abnormalities was: seizure 12 (38,7 %), migraine 5 (16,1 %), confusional state 4 (12,9 %) and posterior reversible encephalopathy syndrome (PRES) 3 (9,6 %). Regarding the subgroups of stroke mimics, out of 22 patients with seizure, 12 (54,5 %) showed perfusion alteration: hypoperfusion in postictal period (11 subjects) and hyperperfusion in status epilepticus (1); the distribution of perfusion changes was multilobar (7 patients), lobar (3), cortical ribbon (1) or holohemispheric (1) sparing basal ganglia. Among 10 patients with migraine, 5 (50 %) demonstrated abnormal perfusion CT as holohemispheric (3) or lobar (2) hypoperfusion, all presenting with aura.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Out of 6 patients with PRES, 3 (50 %) presented bilateral hypoperfusion. No patients with aforementioned mimicking aetiologies caused strokelike hypoperfusion pattern, involving and restricted to a vascular territory. CONCLUSION Perfusion CT is a valuable method for recognition of entities mimicking acute stroke. Different perfusion patterns can be identified in such entities. Their knowledge helps to establish the correct diagnosis and therapy and to avoid an unnecessary thrombolytic treatment with its potentially harmful reactions. Keywords Stroke mimic, perfusion CT, seizure CO.01.03 TEMPORAL CHANGES OF DIFFUSION KURTOSIS IMAGING IN STROKE PATIENTS P. Raab1, M. Heeren2, F. Donnerstag1, E. Bültmann1, P. Dellani1, M. Hennig2, K. Weißenborn2, H. Lanfermann1 1 2

Neuroradiology, Hannover Medical School, Hannover, Germany, Neurology, Hannover Medical School, Hannover, Germany

PURPOSE Diffusion kurtosis imaging has been applied to ischemic stroke in animal models as well as patients [1–3], showing its ability to characterize microstructural tissue changes. The goal of this study is to evaluate the temporal changes of diffusion kurtosis metrics in stroke patients. METHOD In this IRB approved and patient consented study we prospectively performed diffusion kurtosis imaging within 1 day of symptom onset, at day 7 and 3 months after the ischemic insult in stroke patients. 25 patients were included; due to quality reasons or patient drop outs we could analyze 17 time point 1 datasets, 14 time point 2 datasets and 9 time point 3 datasets (11 lacunar infarctions, 12 territorial infarctions). Diffusion kurtosis metrics were calculated as described by Tabesh et al. [4]. Region of interest borders were manually placed around the ischemic tissue based on the elevated diffusion signal and reduced mean diffusivity. Data of time points were compared using ANOVA with control for multiple comparisons. RESULTS Between time points 1 and 2 the gradual increases of day-1decreased diffusivity values and decreases of day-1-increased kurtosis values did not reach significance levels for whole stroke ROIs, all values of time point 3 differed significantly from time points 1 and 2 (decrease of kurtosis parameters, increase of diffusivity parameters). Axial kurtosis shows the largest absolute percent change compared to normal tissue on day 1 and 7. Fractional anisotropy (FA) absolute percent change did show a gradual decrease during time points 1 to 3, being significant on LSD-ANOVA analysis and just missing significance level with Bonferroni correction (p <0.068) for time point 1 vs. 2. CONCLUSION Until day 7 after ischemic stroke the diffusional kurtosis measurements remain relatively stable while FA is gradually decreasing. The dominating axial kurtosis changes are indicating microstructural axonal changes, which is in concordance with previously published data.

1. 2. 3. 4.

Hui, E.S., et al., Stroke, 2012. 43(11): p. 2968–73. Cheung, J.S., et al., Stroke, 2012. 43(8): p. 2252–4. Hui, E.S., et al., Brain Research, 2012. 1451: p. 100–109. Tabesh, A., et al., Magn Reson Med, 2011. 65(3): p. 823–36.

Keywords Stroke, diffusion kurtosis, microstructure

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CO.01.04 REGIONAL LEPTOMENINGEAL SCORE (RLMS) ON COMPUTED TOMOGRAPHY ANGIOGRAPHY/PERFUSION (CTA-CTP) CAN PREDICTS CLINICAL OUTCOMES IN PATIENTS WITH ACUTE ISCHEMIC STROKE (AIS) E. Puglielli1, M. Varrassi1, M. Fuschi1, V. Di Egidio2 1 Interventional and Vascular Radiology, G. Mazzini Hospital, Teramo, Italy, 2General and Interventional Radiology, S. Spirito Hospital, Pescara, Italy

PURPOSE Aim of this study was to systematically review the importance of rLMs in the outcome after AIS and identify a reliable score system for grading collateral flow. METHODS 78 consecutive patients with AIS (mean age 58,7y, April 2009-April 2013), on-set less than 6 hours for the anterior circulation and 12 for the verbtebrobasilar one, undergoing to endovascular multimodal treatment after basal CT, Computed Tomography Angiography/Perfusion (CTA-CTP). The rLMs is based on scoring pial and lenticulostriate arteries (0, no; 1, less; 2, equal or more prominent compared with matching region in opposite hemisphere) in 6 ASPECTS regions (M1-6) plus anterior cerebral artery region and basal ganglia. Pial arteries in the Sylvian sulcus are scored 0, 2, or 4. Good clinical outcome was defined as mRSor=0.30 for all comparisons). In multivariable analysis, the rLMs (good versus poor: OR, 15.8; 95 % CI, 3.3 %-97.4 %; medium versus poor: OR, 9.5, 95 % CI, 1.7 %50.6 %), age (< 80 years), baseline ASPECTS (> or=8), and CTP were independent predictors of good clinical outcome. CONCLUSION Nowadays CT offers a number of practical advantages over other cerebral perfusion imaging methods, including its wide availability and the rLMs appear to be as a strong imaging parameter for predicting clinical outcomes in patients with AIS and can therefore be used for imaging based patient selection. However efforts to determine biological factors of collateral status are however needed. Keywords Stroke, diagnostic, perfusion CT CO.01.05 FALSE ISCHEMIC PENUMBRAS IN CT BRAIN PERFUSION STUDIES IN PATIENTS WITH ACUTE ISCHEMIC STROKE (AIS) E. Puglielli1, M. Varrassi1, M. Fuschi1, V. Di Egidio2 1

Interventional and Vascular Radiology, G. Mazzini Hospital, Teramo, Italy, General and Interventional Radiology, S. Spirito Hospital, Pescara, Italy

2

PURPOSE The introduction of thrombolysis has changed the goals of neuroimaging, and Computed Tomography Angiography/Perfusion (CTACTP) plays a pivotal role in the diagnosis and treatment of acute ischemic stroke (AIS).

S29 METHODS 78 consecutive patients with AIS (mean age 58,7y, April 2009-March 2013), undergoing to endovascular multimodal treatment after basal CT, CTA/CTP. On CTP was calculated the time to peak enhancement TTP, mean transit time MTT, and cerebral blood volume CBV, important parameters for differentiating between an ischemic penumbra. A false delayed peak enhancement or increased mean transit time in a region with normal or only slightly abnormal cerebral blood volume was suggestive for an ischemic penumbra (Internal Carotid plaques, Anatomic Abnormality, Benign Oligemia) that leading to a false appearance of penumbra. Clinical history and findings at basal CT, Angiography or CTAwas correlated with PCT data with a regression analysis. Good clinical outcome was defined as mRS<2 at 90 days. RESULTS CTA can well define the occlusion site, depict arterial state, grade collateral blood flow, and characterize atherosclerotic status (96.15 % [75/78]), whereas PCT accurately delineates the infarct core and the ischemic penumbra (97.43 % [76/78]) p<005. False penumbras, each of which produces a different pattern at imaging were: upstream flow restriction (3.84 % [3/78]), evolution of ischemic change (2.56 % [2/78]), vascular dysregulation (1,28 % [1/78]), positioning of the patient’s head at an angle during image acquisition (1.28 % [1/78]), and variant anatomy in the circle of Willis (6.41 % [5/78]), (p<005). CONCLUSION Nowadays CT offers a number of practical advantages over other cerebral perfusion imaging methods, including its wide availability and Perfusion appear to be as a strong imaging parameter for predicting clinical outcomes in patients with AIS. Nevertheless familiarity with the imaging patterns and causes of false penumbras may increase the radiologist’s confidence in diagnosis. Keywords Stroke, diagnostic, cerebrovascular CO.01.06 MOTOR FUNCTION RECOVERY PREDICTION IN PATIENT WITH ACUTE ISCHEMIC STROKE USING DIFFUSION TENSOR IMAGING T. Popova, R. Konovalov, M. Maksimova, M. Krotenkova FSBI «Research Center of Neurology» under the RAMS, Moscow, Russia PURPOSE to investigate diffusion tensor imaging (DTI) potential for corticospinal tracts (CST) assessment to predict functional outcome in patients with acute ischemic stroke. MATERIALS AND METHODS 47 patients (28 men) with primary acute ischemic stroke in carotid artery system were examined on 1st day, 14th day, 21st day since stroke onset. Fractional anisotropy (FA) of CST was measured in both hemispheres in posterior limb of internal capsule (PLIC) and cerebral peduncle (CP). Neurological status was assessed using NIHSS and mRS (modified Rankin scales) on 1st and 21st days and BI (modified Barthel index) – on 21st day. RESULTS Using total score of unified scales patients were divided in two groups: with satisfactory (group A, n=22) and unsatisfactory (group B, n=25) outcomes of motor function recovery by the end of acute period. In B-group mean FA in ipsilateral PLIC was: 1st day – 0.708[0.647;0.732], 14th day – 0.485[0.426;0.598], 21st day – 0.41[0.303;0.448]; in ipsilateral CP: 1st day – 0.746 [0.703;0.79], 14th day – 0.554[0.423;0.648], 21st day – 0.473[0.381;0.562]. Significant decrease of CST FA was founded in Bgroup in PLIC and CP on 14th and 21st days (Mann–Whitney Test p<0.05). No significant changes of FA were detected dynamically in ipsilateral and contralateral CST in A-group (Mann–Whitney Test p >0.05). CONCLUSION DTI allows to assess changes in fiber tracts beyond acute ischemic stroke area during acute period. Significant alterations of CST were

S30 identified using DTI on 14th day from onset in patients with unsatisfactory recovery of motor function. DTI can be applied for motor function recovery prediction in patients with acute ischemic stroke. Keywords Stroke, DTI, corticospinal tract CO.01.07 DISTINCTION BETWEEN EXTRAVASATED IODINATED CONTRAST AGENT AND PARENCHYMAL HAEMORRHAGE IN MR IMAGING - AN IN-VITRO AND ANIMAL STUDY O. Nikoubashman1, F. Jablawi3, E. Yousefian1, L. Tanrikulu3, A. Woitok2, T. Stopinski2, R. Tolba2, J. Schulz4, H. Clusmann3, M. Wiesmann1 1

Klinik für Diagnostische und Interventionelle Neuroradiologie, Uniklinik Aachen, Aachen, Germany, 2Institut für Versuchstierkunde, Uniklinik Aachen, Aachen, Germany, 3Klinik für Neurochirurgie, Uniklinik Aachen, Aachen, Germany, 4Klinik für Neurologie, Uniklinik Aachen, Aachen, Germany PURPOSE To investigate whether extravasated iodinated contrast agent that may ooze into the brain parenchyma during neurointerventional procedures can be distinguished from haemorrhage in MR imaging. METHODS We analysed the T1-, T2-, T2-FLAIR-, and T2*-signal behaviour of different concentrations of iodinated contrast agent (iopamidol) and saline solution in a phantom model. Furthermore, we analysed the MRI signal behaviour of intraprenchymal iopamidol in an ex vivo porcine brain model. RESULTS High concentrations of iopamidol lead to marked T1 and T2 shortening compared to saline solution, while the effect in T2* and T2-FLAIR imaging was small in the phantom model. Intraparenchymal iopamidol caused no visually distinctive signal changes in the ex vivo porcine brain model. CONCLUSIONS Our data suggest that it is possible to distinguish intraparenchymal haemorrhage from extravasated iopamidol in the brain parenchyma based on MRI. Keywords Iodinated contrast agent,T2*, MRI CO.01.08 HAEMORRHAGE/CONTRAST STAINING AREAS AFTER MECHANICAL INTRA-ARTERIALTHROMBECTOMY IN ACUTE ISCHEMIC STROKE: IMAGING FINDINGS AND CLINICAL SIGNIFICANCE O. Nikoubashman1,2, M. Gindullis2, K. Frohnhofen1, R. Pjontek1, M. Brockmann1, A. Reich2, J. Schulz2, M. Wiesmann1 1 University Hospital Aachen, Department of Diagnostic and Interventional Neuroradiology, Aachen, Germany, 2University Hospital Aachen, Department of Neurology, Aachen, Germany

PURPOSE Investigation of the clinical significance of postinterventional cerebral hyperdensities (PCHD) after endovascular mechanical thrombectomy in acute ischemic stroke. METHODS Retrospective analysis of data of 102 consecutive patients who received postinterventional CT scans within 4.5 h after mechanical thrombectomy . RESULTS PHCD was present in 62 of 102 patients (60.8 %). PCHD were persisting after 24 hours in 13 of 62 patients (21.0 %), and

Neuroradiology (2013) 55 (Suppl 1):S15–S159 transient within 24 hours in the remaining 49 patients (79.0 %). The basal ganglia were the most common site of PCHD. Parenchymal haemorrhage was diagnosed in 4 patients without PCHD and 4 patients with PCHD. Neither ASA, nor Clopidogrel, Tirofiban or rtPA could be identified as risk factors for PCHD. Final infarction size was congruent with or bigger than areas of PPHD in 93.3 % of cases. CONCLUSION PCHD could not be determined as a risk factor for parenchymal haemorrhage in our series. PCHD is a strong predictor for final infarction size. The presence of PPHD is also strongly related to the prior presence of infarction. Keywords Stroke, haemorrhage, thrombectomy CO.01.09 INTRACRANIAL ANEURYSM AS AN ATHEROSCLEROTIC DISEASE A. Grams1, B. Glodny2, E. Maenner2, E. Schoenherr2, R. Helbok3, J. Petersen2 1

Department of Neuroradiology, Innsbruck Medical University, Innsbruck, Austria, 2Department of Radiology, Innsbruck Medical University, Innsbruck, Austria, 3Department of Neurology, Innsbruck Medical University, Innsbruck, Austria PURPOSE Besides the known risk factors such as aortic isthmic stenosis, polycystic kidney disease and connective tissue diseases for the development of intracranial aneurysms, an impact of classical cardiovascular risk factors is assumed. Due to the fact that these factors are not provable retrospectively, the aim of the present study was to examine, if intracranial aneurysms are associated with atherosclerosis, its risk factors and sequelae. METHODS In 241 patients (60.2 % male, 29.8 % female, mean age 58.8±11.5 years) with subarachnoid hemorrhage simultaneously acquired CTs of the cerebral arteries and the trunk, imaging data was evaluated retrospectively from the time period between 2002 and 2012. Thoracal and abdominal arteriosclerosis was quantified with a calcium scoring method in the patients and an age and gender matched control group. In addition cortical thickness was measured and the adrenals were assessed. RESULTS Overall 297 aneurysms were found in 189 patients (240 anterior and 57 posterior circulation). The abdominal aortic diameter was higher in the patients than in the control group with 22±3 mm versus 21.1±2.7 (p<0.0001). Thoracal and abdominal arteriosclerosis was found to be significantly higher (p<0.0001) in patients (0.26±0.7 and 0.41±0.77) than in the control group (0.07±0.36 and 0.21±0.6 ml). In patients a slimmer renal cortex was found than in the control group with 5.7±1.1 mm versus 7.6±2.0 mm on the right side and 5.9±1.1 mm versus 7.3±1.7 on the left side (p<0.0001 respectively). In addition adrenal adenomas were found in 37 of 136 patients but only in 3 of 136 members of the control group. CONCLUSIONS In patients with cerebral aneurysms the quantifyable atherosclerotic burden in large vessels is much more pronounced than in a control group. Additionally, volume decrease of the renal cortex indicates concomitant microangiopathy. The higher incidence of adrenal adenomas in patients with cerebral aneurysms suggests a secondary cause of arterial hypertension in some cases. For secondary prevention of cerebral aneurysm development and rupture clarification of common and uncommon causes for arteriosclerosis seems to be reasonable. Keywords Cerebral aneurysm, arteriosclerosis, adrenal adenoma

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CO.01.10 BOLD-BASED MRI REVEALS HYPOXIC AREAS IN PATIENTS WITH STROKE OR SEVERE ARTERIAL STENOSIS A. Gersing1, M. Ankenbrank1, V. Toth1, S. Wunderlich2, C. Zimmer1, C. Preibisch1 1 Department of Neuroradiology, Technical University Munich, Munich, Germany, 2Department of Neurology, Technical University Munich, Munich, Germany

PURPOSE Hypoxia plays an important role for prognosis in stroke. In this study, we applied a new method based on the quantitative BOLD effect for assessment of relative oxygen extraction fraction (rOEF) in patients with stroke or strong arterial stenosis. We investigated if a protocol with an additional measurement time of 3.5 minutes could provide diagnostic valuable maps of rOEF. The potential prognostic value of this method is compared with the established DWI/PWI mismatch method. METHODS 13 patients (71.5±11.9y; 7 males) with suspected acute (6 patients) and subacute ischemia (3 patients) or severe carotid artery stenosis (4 patients) were examined on a 3 T Philips Achieva scanner. In addition to the standard clinical protocol (FLAIR, DWI, T2*w, PWI (DSC: EPI, 40 dynamics during CA bolus application; TTP, MTT, CBF, CBV) and TOF), quantitative measurements of T2 (multi-echo GRASE) and T2* (multi-GE) were performed (20 slices, voxel size 2.33x2.33x4 mm3). As a measure for hypoxia rOEF=R2‘/(c*CBV) was calculated with R2‘=(1/T2*)-(1/T2) and c=4/3*π*γ*delta(χ)*B0=317Hz at 3 T. It was compared with the established method of the DWI/PWI mismatch by two independent experts and correlated with clinical outcome in order to evaluate its prognostic value and validity for therapeutic implications. RESULTS 9 patients (3 with an acute, 3 with subacute ischemia and 3 with stenosis with ischemia) showed a prolonged TTP over 4 sec. A significant DWI lesion was seen in 7 patients, 3 with acute, 2 with subacute stroke ischemia, and 2 with stenosis with ischemia. On the lesion side in areas with prolonged TTP (>4 sec) without diffusion restriction, rOEF presented a signal intensity increase from 0.59±0.19 to 1.44±0.85 (p=0.077). In regions with diffusion restriction this effect was less pronounced (1.03±0.62, p=0.082). rOEF lesion was associated with TTP lesion (p=0.12). Longer TTP values correlated with rOEF value increase (r=0.50, p<0.05). CONCLUSIONS Measurement of rOEF identifies ischemic areas and detects signal intensity differences between ischemic core and surrounding tissue. rOEF values correlate with perfusion prolongation. We assume that areas with rOEF increase represent tissue with potentially reversible metabolic function. Further work is needed to delineate the utility of rOEF for the penumbra concept. Keywords Stroke, BOLD-based MRI, hypoxia SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 2 16:00–18:00 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - DIAGNOSTIC ADVANCED MRI-TECHNIQUES S.17.01 USE OF BOLD SEQUENCES AND HYPEROXIA IN THE ASSESSMENT OF BRAIN TUMOR VIABILITY J. Martinez Barbero1, A. Luna Alcala1, L. Alcala Mata1, T. Martin Noguerol1, J. Sanchez2

S31 1 Clinica Las Nieves, Sercosa, Grupo Health Time, Jaen, Spain, 2Philips Healthcare España, Madrid, Spain

Up to date, there are many ways to evaluate tumoral perfussion and microvascularisation such as IVIM, ASL,CT-P, DCE-MRI… but none of them studies tumor oxygenation. BOLD effect has been largely used since 1990 for the evaluation of intracranial structures with many different approaches, especially in funtional-MRI, but it can also be used in tumor assesment.The connection between changes in BOLD sequences and tissue oxygenation can be explained through the relationship between oxygen and hemoglobin in the blood. Deoxyhemoglobin has an iron atom that directly influences the magnetic fields producing a local signal drop. The blood flowing through arteries has a high percentage of free or oxygen bound to hemoglobin. When blood goes through the tissue, the oxygen is released from hemoglobin and absorbed by tissue, reducing the percentage of oxygen in vessels and increasing relative levels of deoxyhemoglobin How do we do it? 1. Acquire a T1 mFFE sequence… 2. Obtain a T2* estimation after turning every pixel into a monoexponential decay model . 3. Make measurements of Signal Intensity in each ROI at T2* maps, and transform measures into RT2 to make data more reproductible and reliable. 4. Repetitive measurements of RT2 signal at basal level and then in certain moments after inhaled oxygen. Learning objectives 1. Show our experience in the design of T2* BOLD sequence for the brain 2. Become familiar with the effects of hyperoxia on T2* signal decay on brain tumors 3. Discuss and relationship between local variations on T2* signal and_tumor viability and vascularization, and its clinical applications. Summary BOLD MRI with hyperoxia allows to measure tumoral angiogenesis and hypoxia in the brain_ BOLD MRI may have a clinical role in tumor characterization, postreatment monitorization and prediction of response to treatment Keywords Brain tumor, bold, hyperoxia S.17.02 SUPERSELECTIVE PCASL – FIRST CLINICAL RESULTS WITH A NOVEL MRI METHOD FOR INDIVIDUAL CHARACTERIZATION OF INTRACEREBRAL PERFUSION V. Tóth1, M. Helle2, A. Förschler1, C. Zimmer1, C. Preibisch1 1

Dep. of Neuroradiology, Klinikum rechts der Isar, Munich, Germany, Philips Technologie GmbH, Innovative Technologies, Research Laboratories, Hamburg, Germany 2

INTRODUCTION Superselective pseudocontinuous arterial spin labeling (pcASL) is a novel ASL approach, where a circular spin labeling spot enables targeted specific vessel labeling even in difficult anatomical situations with elongated vessels. 1, 2 Thus, non-invasive imaging of altered perfusion territories is possible in patients with cerebrovascular stenoocclusive disease. Patients with multiple extracranial stenoses and cerebral infarcts often present a diagnostic conundrum with a difficulty to determine the currently symptomatic vessel. The unique possibility of pcASL to overlay selective perfusion maps on diffusion weighted images helps answering the question of infarct origin. SUBJECTS AND METHODS 20 patients with previously diagnosed multiple extracranial stenoses and TIAs of unclear origin were examined in a Philips Achieva 3.0 T

S32 MR. In addition to standard clinical protocol (FLAIR, DWI, T2*w and TOF MRA) superselective pcASL was performed with labeling of 3–6 extracranial arteries. In 10 cases, contrast enhanced perfusion with bolus tracking (DSC) was also performed. Comparison of two postprocessing softwares (Philips iViewBOLD and Brainlab BOLD Analysis) was performed in 10 cases. In 3 cases, MRI results could be correlated with DSA reports. Volumetry was performed in Brainlab iPlanCranial 3.0 (Brainlab, Feldkirchen, Germany). RESULTS Overall, labeling of 3 vessels (mean 3.3±0.78) was necessary, resulting in an additional imaging time of 7:15 minutes. Technical performance was robust. Online evaluation with the iViewBOLD software was reliable and reproducable. Correlation with DSA showed absolute accordance. Comparing DSC TTP and global pcASL, normally perfused regions were overlapping with a non-significant difference (p=0.01). Percentage of perfusion volumes per vessel correlated significantly with stenosis grade (r.0.6, p<0.05). DWI lesions could be assorted to a specific perfusion territory in all cases. DISCUSSION First clinical results with the novel superselective pcASL method for selective perfusion territory imaging in cerebrovascular stenoocclusive disease yielded meaningful findings in 20 patients with influence on clinical decisions. The method performed well in validation against cDSA and contrast enhanced perfusion measurements. Keywords pcASL, selective, stenoocclusive disease S.17.03 DIFFUSION KURTOSIS IMAGING IN GRADING OF BRAIN GLIOMA MALIGNANCY A. Tonoyan1, I. Pronin1, L. Fadeeva1, D. Pitskhelauri1, L. Shishkina1, A. Ektova1, F. Grinberg2, E. Farrher2, V. Kornienko1 1

Burdenko Neurosurgery Institute, Neuroradiology, Moscow, Russia, Forschungszentrum Juelich, Institute of Neuroscience and Medicine 4 Medical Imaging Physics, Juelich, Germany

2

PURPOSE Conventional diffusion tensor imaging (DTI) is a powerful tool of characterizing tissue microstructure. Recently, diffusion kurtosis imaging (DKI) has been introduced as an advanced extension of DTI that yields, in addition to conventional diffusion metrics, the estimate of diffusion kurtosis (DK). DK is related to the degree of deviation from the Gaussian model, assumed by DTI, and provides an improved characterization of tissue microstructure. The goal of this study is to assess the diagnostic efficacy of DKI in brain glioma grading. METHODS 40 patients with cerebral gliomas underwent imaging with a 3-T MR scanner. A spin-echo EPI sequence was used to acquire DKI using b values of 0, 1000 and 2500 s/mm2 and 60 gradient directions. The diffusion tensor (DT) parameters (fractional anisotropy (FA), mean diffusivity (MD)) and the DK parameters (mean kurtosis (MK), axial kurtosis (AK) and radial kurtosis (RK)) were compared in the solid parts of 14 grade-I-II astrocytomas, 12 grade-III astrocytomas and 14 gradeIV astrocytomas. The same parameters in the solid parts of tumors were also compared among glioma grades after the normalization to the corresponding values in contralateral normal-appearing white matter and after age correction. RESULTS DK parameters significantly differed between gliomas grades. MK, AK and RK values increased with higher glioma malignancy. DT parameters differed between gliomas grades, but not significantly. FA increased with higher glioma malignancy, whereas MD tended to decrease with that. Both DK and DT parameters, normalized to the corresponding values in contralateral normal-appearing white matter, were

Neuroradiology (2013) 55 (Suppl 1):S15–S159 significantly different between gliomas grades. Diffusion parameter values of peritumoral edema differed between gliomas grades, but not significantly. Peritumoral edema values of FA, AK, RK and MK increased with higher glioma malignancy. Demonstrated sensitivities and specificities for discriminating between the groups were higher for DK parameters and for normalized DK parameters, than for the corresponding values of DT parameters. The highest sensitivity and specificity for that were found for MK and MK normalized to the value in contralateral normal-appearing white matter. CONCLUSION DKI demonstrated high efficacy to differentiate among brain glioma grades. The method allowed better to discriminate glioma grades in comparison with DTI. Keywords Diffusion kurtosis, diffusion tensor, brain glioma S.17.04 REGIONAL SPECIFICITY OF fMRI, DTI, AND MRS DATA IN SUBSTANTIA NIGRA (SN) FOR CHARACTERISTICS OF THE LEVEL OF COGNITIVE IMPAIRMENT (CI) IN PATIENTS WITH PARKINSON’S DISEASE (PD) Z. Rozhkova1, O. Omelchenko1, I. Karaban2, N. Karasevich2 1

Medical Clinic BORIS, Department of Radiology, Kiev, Ukraine, Institute of Gerontology, Department of Extrapyramidal Disorders, Kiev, Ukraine

2

PURPOSE We try to find biomarkers that characterize SN neurodegeneration in patients with PD, and investigate potential regional specificity of fMRI, DTI, and MRS data for characteristics of the cortical connectivity, microstructural abnormalities in SN, and peculiarities of the local metabolic state of the brain in patients with PD and different level of CI. METHODS Three groups of PD-patients with various cognitive statuses are studied by fMRI, DTI, and 1H MRS with 1.5 T SIGNA (GE). The 1st group (DPDG):13 patients with dementia. The 2nd group (CIPDG):23 PDpatients with mild CI. The 3rd group (NPDG):18 PD-patients with normal cognitive function. Resting state fMRI data and simple unilateral finger tapping task are used:TR/TE=3000/60 ms. Model based on two step ICA analyses was carried out with GLM and ICA (FSL5.0 software package):FEAT, and MELODIC. DTI-data (25 directions) are obtained in ROI=2x2x2mm in the anterior, medial, and posterior SN (ASN, MSN, PSN). Spectra are recorded with the SVSSTEAM:TR/TE=1500/144 ms. RESULTS From fMRI data we have found out differences between the total activation areas in patients of all groups. In the NPDG connections between the APCG and PPCG, and inferior parietal gyrus bilaterally were found. In the NPDG activation of the anterior (APCG), and of the posterior portion of cingulate gyrus (PPCG) decreased, but connectivity patterns persisted.In DPDG no activation in PPCG were found but smaller clusters in the cuneal and precuneal region. In anterior part of SN (APSN) the mean values of NAA/Cr in DPDG, CIPDG, and NPDG are:(1.68+−0.02), (2.04+−0.03),(2.32+−0.05), and Cho/Cr:(0.84+−0.02), (0.81+−0.05),(0.53+−0.03). In posterior part of SN (PPSN) the mean values NAA/Cr in DPDG, CIPDG, and NPDG are:(1.14+−0.12), (1.81+−0.02), (1.98+−0.04), and Cho/Cr:(0.96+−0.02), (0.77+−0.03),(0.68+−0.03).We have found the progressive decreasing NAA/Cr in the PPSN and increasing of Cho/Cr for the patient of NPDG, CIPDG, DPDG, that is associated with poorer cognitive function. Mean diffusivity (MD) in DPDG are:(0.82 + −0.05)x10-3 mm2/s, in CIPDG:(0.74+−0.05)x10-3 mm2/s, in NPDG:(0.71+−0.05)x10-3 mm2/s. The MD changes are most pronounced in APSN. Fractional anisotropy (FA) are:(0.41+−0.05), (0.43+−0.05),(0.47+−0.05) in DPDG, CIPDG, NPDG, respectively. We have found that FA have non-significant tendency to decrease in PD-patients with various level of CI.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSION fMRI, DTI, and MRS-data give us new approach for understanding pathophysiological changes in PD-patients associated with CI. Keywords fMRI, Parkinson's disease, in-vivo MRS S.17.05 USEFULNESS OF BRAIN PERFUSION MAPS OBTAINED WITH ARTERIAL SPIN LABELING IN REFRACTORY EPILEPSY N. Bargallo1, A. Sierra2, X. Setoain1, M. Carreño2, A. Donaire2, J. Rumia2 CDIC. Hospital Clinic i Provincial, Barcelona, Spain, 2Institut de Neurociencies, Hospital Clinic i Provincial, Barcelona, Spain 1

PURPOSE The aim of this study is to determine the usefulness of Arterial Spin Label in clinical diagnosis of refractory epilepsy. MATERIAL AND METHOD This is an exploratory study. We have performed perfusion maps using ASL in all patients monitored in the epilepsy unit during the last year in our hospital . Forty-five patients were included, 26 females and 18 males ( mean age 35 years; age range 4–66.).All the patients undergone video EEG monitoring, 3 T scan MRI exam with dedicated epilepsy protocol consisting in 3D FLAIR, coronal DIR , Coronal T2WI., 3D T1 MPRAGE and axial T2WI and pulsed ASL. Relative CBF maps were generated using manufacture software ( 3D NEURO; Siemens) and corregistred with 3D FLAIR Image. PET or SISCOM data were obtained in all patients; (28 and 32 respectively). Kappa and Kendall’s coefficients of concordance were obtained between structural MRI, ASL, PET and SPECT images. RESULTS 36 patients ( 80 %) show structural lesion on MR examination and 9 (20 %) subjects show negative MRI. Finding observed were: 13 mesial sclerosis, 5 of them with temporal pole signal abnormalities, 6 tumours, 6 cortical dysplasia, 4 enlarged amygdale ( possible hamartoma or dysplasia), 3 heterotopias, 2 Rasmussen or chronic encephalitis , 1 polimicrogyria , and 1 posttraumatic malacic changes. In 4 patients the ASL data was to much degraded by movement artifacts that was dismissed . rCBF maps showed abnormalities in 24 patients ( 58,5 %) and was negative in 17 patients ( 41,5 %). Decreased on rCBF maps was detected in 18/24 patients (40.9 %) and increased rCBF in 6/24 ( 13,3 %). Statistically significant concordance were observed between structural MRI and ASL perfusion maps (0.53 Tau-b de Kendall and 0.92 Kappa) and between PET and ASL perfusion maps((0.31. Tau-b de Kendall and 0.49 Kappa). However no significant concordance was observed between ASL perfusion maps and SISCOM. (0.15Tau-b de Kendall and −0.13 Kappa). CONCLUSION ASL perfusion map is a new tool that can detect abnormalities in patients with refractory epilepsy. Given the correlation between ASL and PET perfusion, ASL could become part of the standard work-up in patients with epilepsy. Keywords Epilepsy, arterial spin labeling, MRI S.17.06 ARTERIALSPIN-LABELINGMRIMAGINGINMENINGOENCEPHALITIS T. Noguchi, M. Nishihara, Y. Hara, T. Hirai, H. Irie Department of Radiology, Faculty of Medicine, Saga University, Saga City, Japan

S33 PURPOSE Arterial spin-labeling MR imaging (ASL-MRI) provides brain perfusion information noninvasively. Our purpose was to identify the ability and pattern of the abnormal findings on ASL-MRI in meningoencephalitis. MATERIALS and METHODS 25 patients were clinically diagnosed as meningoencephalitis based on cerebrospinal fluid pleocytosis and elevated cerebrospinal protein level as well as abnormal findings of brain on FLAIR. They underwent pulsed ASL-MRI, or quantitative imaging of perfusion with thin-slice TI1 periodic saturation(Q2TIPS) using 1.5 T- or 3.0 T-MRI. Firstly, we assessed the imaging quality of ASL-MRI. Secondly, we divided the pattern of disease into the parenchymal involvement and the meningeal involvement based on the findings on FLAIR and estimated the agreement rates with those findings on ASL-MRI. RESULTS Four of 25 patients (16 %) were determined to have a suboptimal imaging quality of ASL-MRI due to movement artifacts. The diagnostic accuracy of ASL-MRI was sensitivity 39 %, specificity 92 %, and accuracy 64 % for the detection of parenchymal involvement, and 53 %, 100 %, and 64 % for the detection of meningeal involvement compared to FLAIR. CONCLUSION ASL-MRI can preserve the imaging quality even in patients with meningoencephalitis. ASL-MRI had high specificities in both the parenchymal and the meningeal involvement. ASL-MRI might be useful to improve diagnostic confidence for meningoencephalitis in conjunction with FLAIR. Keywords Arterial spin-labeling, meningoencephalitis, MRI S.17.07 INTRAVOXEL INCOHERENT MOTION DIFFUSION-WEIGHTED MR IMAGING OF GLIOMAS: FEASIBILITY OF THE METHOD AND INITIAL RESULTS S. Bisdas1, C. Roder2, C. Braun3, U. Klose1, E. Ernemann1 1 University of Tübingen, Department of Neuroradiology, Tübingen, Germany, 2University of Tübingen, Department of Neurosurgery, Tübingen, Germany, 3University of Tübingen, Department of Neurology, Tübingen, Germany

PURPOSE To evaluate the feasibility of intravoxel incoherent motion (IVIM) imaging and its value in differentiating the histologic grade among human gliomas. METHODS The IVIM model generated parametric images for apparent diffusion coefficient ADC, slow diffusion coefficient Dslow, fast diffusion coefficient Dfast, and fractional perfusion-related volume f in 22 patients with gliomas (WHO Grade 2 & 4) using monopolar Stejskal-Tanner DWI scheme and 14 b values ranging from 0 s/mm2 to a maximum of 1300 s/mm2. A region-of-interest (ROI) analysis on the tumor as well as in the white matter was conducted. The parameter values were tested for significant differences. The repeatability of the measurements was tested by coefficient of variation and Bland-Altman plots. RESULTS Dfast/slow, and f in the high-grade gliomas demonstrated significant differences compared to the healthy white matter. Dfast and f showed a significant difference between low- and high-grade gliomas. Dslow tended to be slightly lower in the WHO grade II compared to WHO grade IV tumors. f and Dfast demonstrated higher coefficients of variation than the ADC and Dslow in tumor. The Bland-Altman plots demonstrated satisfactory results without any outliers outside the mean±1.96 SD.

S34 CONCLUSIONS The IVIM-fitted post-processing of DWI-signal decay in human gliomas could show significantly different values of fractional perfusion-related volume and fast diffusion coefficient between low- and high-grade tumors, which may enable a noninvasive WHO grading in vivo. Keywords Gliomas, DWI, perfusion S.17.08 POTENTIAL CLINICAL APPLICATIONS OF ULTRA-HIGHFIELD MRI (7T) OF THE CENTRAL NERVOUS SYSTEM J. Johnson, J. Polimeni, E. Ratai, B. Keil, L. Wald, S. Stufflebeam, B. Rosen, J. Romero Massachusetts General Hospital, Boston, MA, USA PURPOSE To discuss the advantages of ultra-high-field (7 T) imaging and their potential clinical applications. METHODS Scanning was performed on a 7 T whole-body imager (Siemens, Erlangen, Germany) using a whole body gradient (Gmax= 70mT/m, SR=200 T/m/s) and a custom-built birdcage transmit coil with a 32channel receive array for the head and a custom-built 4-channel transmit coil (used in single-transmit) with a 19-channel receive coil for the spine. The 7.0 T system uses a 108-cm warm bore actively shielded magnet (Magnex Scientific, Oxford, UK). The system is equipped with 40 mT/m gradients with a 150 T/m/s available slew rate and a 55 cm patient aperture. Multiple sequences were optimized and evaluated on a combination of healthy volunteers and subjects with central nervous system pathology. These sequences include a magnetization-prepared 180 degrees radio-frequency pulses and rapid gradient-echo (MPRAGE) sequence, a 3D sampling perfection with application optimized contrasts by using different flip angle evolutions (SPACE) sequence, diffusion weighted imaging, susceptibility sensitive sequence (SSS), contrast enhanced dynamic susceptibility contrast perfusion sequence (CE-DSC), magnetic resonance time of flight angiography (MRA TOF), magnetic resonance spectroscopy (MRS) and functional magnetic resonance imaging (fMRI). A multi-echo T2*-weighted fast low angle shot (FLASH) sequence was optimized and evaluated for spine imaging. Images were subjectively evaluated for an increased signal-to-noise (SNR), higher spatial resolution and reduced scanning time. RESULTS Each sequence was felt to achieve a significant increase in SNR and spatial resolution. Given the focus on improved SNR and spatial resolution, imaging time for similar volumes of tissue were equivalent or higher compared to similar 3 T imaging sequences. Achievements include a 500 micron isotropic MPRAGE sequence, an 800 micron isotropic SPACE sequence, 300 micron (in plane) SSS, 1 mm isotropic CE-DSC, 150 micron MRA TOF and reliable MRS and fMRI with improved SNR and resolution. CONCLUSIONS Multiple sequences were successfully optimized for 7 T imaging which have been successfully utilized for the evaluation of epilepsy, demyelinating disease, cerebrovascular disease, inborn errors of metabolism, degenerative spine disease and central nervous system neoplasms. Keywords 7 Tesla MRI, brain, spine

Neuroradiology (2013) 55 (Suppl 1):S15–S159 SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 3 16:00–18:00 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - WHITE MATTER DISEASES S.18.01 MAGNETIC CHARACTERISTICS OF MULTIPLE SCLEROSIS MEASURED BY QUANTITATIVE SUSCEPTIBILITY MAPPING (QSM) Y. Wang, W. Chen, S. Gauthier, T. Liu, J. Communale, A. Gupta Cornell University, New York, NY, USA PURPOSE Tissue magnetism is a property of molecular electrons that respond to an applied magnetic field. For example, unpaired electrons in ferric iron make it highly paramagnetic. Magnetic susceptibility can be detected as a hypointensity in traditional gradient echo (GRE) MRI. However, this blooming T2*/SWI hypointensity varies easily with imaging parameters including TE, B0, object orientation, and voxel size. We have developed quantitative susceptibility mapping (QSM) from the typically ignored phase data in MRI by solving the magnetic field to susceptibility source inverse problem. The deconvolution in QSM removes the blooming artifacts and enables accurate localization and quantification of susceptibility sources. We apply QSM to study in brains of multiple sclerosis (MS) patients the deposition of iron, an essential facilitator of basic biochemical activities of cells. Excessive iron may present in deep gray matter structures including basal ganglia. Pathological iron deposits may present in white matter inflammation sites. The incompletely known iron deposition may be both consequence and promotion of MS pathogenesis. Activated microglia/macrophages express ferritin due to up-regulation of transferrin receptor in response to inflammatory stimuli. Iron overload can lead to oxidative stress damaging macromolecules including proteins, lipids and DNA, and can cause activated microglia increase production of proinflammatory mediators in MS. Additionally, demyelination may also contribute to magnetic susceptibility increase. METHODS All subjects underwent 3 T MRI including 3D multiecho GRE, from which QSM was constructed. Magnetic susceptibilities of MS lesions were studied on 32 clinically confirmed MS patients. To estimate the ages of MS lesions (hypointense on T2 weighted images), all available prior MRIs (performed 0.3 – 10.6 years ago) were examined. MS lesions’ susceptibilities relative to normal appearing white matter (NAWM) were obtained from QSM images. RESULTS We found 162 MS lesions being age measurable with 6 becoming only visible on QSM. The relative susceptibility on average was 1, 35, 42, -2, 1, and 1 ppb (part per billion) for early enhancing lesions (0y), early non-enhancing lesions (0 –2y), lesions aged 2 –4y (none aged 4–6y), 6 – 8y, 8 –10y, and >10y respectively. CONCLUSIONS Magnetic susceptibilities of MS lesions increase rapidly as lesions change from enhancing to non-enhancing, gain high susceptibility relative to NAWM and gradually dissipate as lesions age, which may reflect demyelination activities in MS lesions. Keywords Multiple sclerosis, QSM, magnetic susceptibility

Neuroradiology (2013) 55 (Suppl 1):S15–S159 S.18.02 ASSOCIATION OF MR FEATURES AND CLINICAL PRESENTATION, LEVELS OF ADVANCED OXIDATION PROTEIN PRODUCTS AND TOTALTHIOL CONTENT IN PLASMA AND CSF IN PATIENTS WITH CLINICALLY ISOLATED SYNDROME AND RELAPSING REMITTING MULTIPLE SCLEROSIS D. Stojanov1, S. Ljubisavljevic2, S. Vojinovic2, I. Stojanovic3 1 Center of Radiology, Clinical Center Nis, Nis, Serbia, 2Clinic of Neurology, Clinical Center Nis, Nis, Serbia 3Institute for Biochemistry, Faculty of Medicine University of Nis, Nis, Serbia

PURPOSE To assess association of MR features and clinical presentation, levels of advanced oxidation protein products (AOPP) and total thiol (SH) groups content in plasma and CSF in patients with clinically isolated syndrome (CIS) and relapsing remitting multiple sclerosis (RRMS) patients. Methods: The cross-sectional study included 50 CIS patients (15 male, 35 female), aged 17–57 years, 57 RRMS patients (12 male, 45 female), aged 23–58 years, and 20 control patients (10 male, 10 female), aged 23–45 years with nonspecific neurological symptoms. All CIS and RRMS patient’s clinical presentations were assessed using Extended Disability Status Scale (EDSS). The number of T2W hyperintense lesions and the lesion load of Gdenhancing lesions on T1W images were calculated. The lesion loads were calculated to volumes. AOPP and the amount of total sulfhydryl (SH) groups were estimated in plasma and CSF by the spectrophotometry. RESULTS Total number of T2W lesions [9(0–56) vs .40 (5–84)] and T1WGd enhancing lesions volume (146.5 ± 46 mm3 vs. 277.7 ± 109 mm3) were significantly higher in RRMS than in CIS patients (p<0.05). There was no differences in the number of T1W-Gd enhancing lesions. We found a significant positive correlation between EDSS and T2W lesions number in both study group (p <0.01), but no correlation was observed in EDSS and T1-Gd ehancing lesions volume (p > 0.01). AOPP values were significantly higher in CIS than RRMS patients (p < 0.05), although the total number of T2-weighted lesion was extremely higher in RRMS than in CIS patients ( p<0.05). CIS patients, with lower total brain T2W lesions had higher SH content than in RRMS patients, but comparing the intergroup differences we have confirmed significance only for SH values in CSF (p < 0.05). Although, there were differences in AOPP and SH values regarding the MRI findings, no correlation was observed in examined parameters in the plasma and CSF with Gd-enhancing lesions volume (p>0.01). CONCLUSION We found a significant positive correlation between EDSS and T2W lesions number in CIS and RRMS, but no correlation was observed in EDSS and T1-Gd ehancing lesions volume . Keywords MR, CIS, RRMS S.18.03 BRAINSTEM WHITE MATTER LESIONS ON MRI IN PATIENTS WITH TRIGEMINAL NEURALGIA WITHOUT MULTIPLE SCLEROSIS, OUR CASE SERIES AND REVIEW OF LITERATURE F. D'Arco, A. D'Amico, C. Russo, F. Caranci, B. Carotenuto, N. Di Paolo, M. Marseglia, A. Brunetti

S35 University Federico II Department of Diagnostic Imaging and Radiotherapy, Naples, Italy PURPOSE To investigate the frequency of white matter lesions in brainstem in patients with trigeminal neuralgia and without diagnosis of multiple sclerosis, differentiating between patients with trigeminal neuralgia due to herpes zoster and patients with neurovascular conflict. METHODS MRIs of 55 patients with trigeminal neuralgia were reviewed: 38 with surgical diagnosis of neurovascular conflict (surgically proved), 12 with clinical diagnosis of herpes zoster virus (HZV) infection and 5 patients with trigeminal neuralgia but without a known cause for the trigeminal pain. RESULTS We found 7 patients with T2 hyperintense lesions in the pons (localization consistent with symptoms), 5 with herpes zoster, 1 with neurovascular conflict and 1 among the patients with pain without known ethiology. We have also incorporated our results with data reported in literature. To our knowledge there are only 13 cases of T2 brainstem hyperintensities reported among 54 patients with trigeminal neuralgia related to herpes zoster virus infection (Hanpaa 1998; Kidd 1998; Nagane 2001; Aribandi 2005; Perez Navarro 2007) and 4 cases among 68 patients with trigeminal neuralgia related to neurovascular conflict (Arrese 2008). The overall frequency of brainstem hyperintensities in patients without multiple sclerosis is thus 13,5 % (24 on 177 patients); the frequency of this MRI sign in patients with herpes zoster infection is 27 % (18 on 66 patients) and 4 % in patients with neurovascular conflict (5 on 106 patients). CONCLUSIONS Brainstem hyperintensities could be an MRI sign of trigeminal neuralgia and it is definitely more frequent in case of pain related to viral infection (probably because of the retrograde involvement of the trigeminal nuclei from the virus). Therefore T2 brainstem hyperintensities should be included among MRI features of trigeminal pain. Keywords Trigeminal neuralgia, herpes zoster, neurovascular conflict S.18.04 SUSCEPTIBILITY SIGNAL WITHIN DEMYELINATING PLAQUES IN CLINICALLY ISOLATED SYNDROMES À. Rovira, C. Auger, M. Tintore, J. Canahuiri, G. Santana, C. Montealegre, G. Arrambide, E. Huerga, R. Mitjana, X. Aymerich, X. Montalban Hospital Universitari Vall d'Hebron, Barcelona, Spain PURPOSE Areas of intralesional susceptibility signal (ISS), likely corresponding to iron deposits have been observed by MRI susceptibility-weighted imaging (SWI) in multiple sclerosis (MS) plaques. The purpose of this study was to analyze the presence and pattern of ISS within acute and chronic MS plaques in patients with clinically isolated syndromes (CIS). METHODS In total, 34 subjects (23 females) mean age 33 years, with CIS and focal lesions on T2-weighted images were examined with 3 T MRI (PD/T2, T2-FLAIR, contrast-enhanced T1 and SWI). The MR-examination was performed within 0–5 months after symptoms onset. SWI images were acquired using a 3 mmslice thickness transverse 3D GE sequence (TR/TE=32 ms/24.6 ms). Lesions identified on SWI were classified as follows: (A) uniform dark signal; (B) rim of hypointense signal; (C) central hypointense signal; (D) no hypointense signal; and (E) hypointense but not seen on T2 (E). A group of 8 subjects (mean age 53 years; 7 females) with incidental white matter lesions, in whom a diagnosis of MS was excluded, was used as controls.

S36 RESULTS We found 405 plaques on T2 in the 34 CIS patients (mean 12; 1–43), 62 of them with contrast uptake. Areas of ISS were observed in 164 of the 343 plaques without contrast uptake (48 %): pattern A in 91 plaques, pattern B in 14 plaques, and pattern C in 59 plaques; while pattern D was observed in 177 plaques. Only two lesions were classified as pattern E. ISS were observed in 36 of the 62 plaques with contrast uptake (58 %): pattern A in 15 plaques, pattern B in 4 plaques, and pattern C in 17 plaques; while pattern D was observed in 26 plaques. In the control group, 139 focal lesions were identified, and none of them showed ISS. CONCLUSIONS Intralesional susceptibility signal, likely representing iron deposition, appears in approximately 50 % of visible plaques on T2-weighted sequences (both enhancing and non-enhancing) in patients with CIS, while this finding was absent in all lesions in asymptomatic subjects. This finding should be considered in future studies that assess the specificity of MR imaging in the diagnosis of multiple sclerosis. Keywords Multiple sclerosis, susceptibility-weighted imaging, MRI S.18.05 INFLAMMATORY PERFUSION CHANGES CORRELATE WITH EXECUTIVE FUNCTION DEFICITS IN PATIENTS WITH CLINICALLY ISOLATED SYNDROME E. Papadaki1, P. Simos2, T. Panou3, V. Mastorodemos3, T. Maris4, A. Karantanas1, A. Plaitakis3 1

University Hospital, Department of Radiology, Heraklion, Greece, University Hospital, Department of Psychiatry, Heraklion, Greece, 3 University Hospital, Department of Neurology, Heraklion, Greece, 4 University Hospital, Department of Medical Physics, Heraklion, Greece 2

PURPOSE Patients with Clinically Isolated Syndrome (CIS) demonstrate brain hemodynamic changes, and also suffer from difficulties in processing speed, memory, and executive functions.The aim of this study is to investigate possible correlation between the brain hemodynamic disturbances in CIS patients and the executive function deficits. METHODS Thirty CIS patients (17 women and 13 men, mean age (±SD) of 31.4± 9.6 years) and forty three healthy controls (25 women and 18 men, mean age of 33.6±10.2 years), matched for age, gender, education level and FSIQ, were administered tests of visuomotor learning and set-shifting ability. Using the dynamic susceptibility contrast- MRI perfusion technique, regional Cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) values were estimated in a fine grid of 20 Normal Appearing White Matter (NAWM) and Normal Appearing Deep Gray Matter (NADGM) structures, including those responsible for visuomotor learning and executive function. RESULTS CIS patients showed significantly elevated reaction time (RT) on both tasks and task conditions (with the exception of Simple blocks in the Complex Decision Task) compared to healthy controls, without evidence of reduced performance accuracy, while their CBVand MTT values were increased,across all 20 ROIs, probably due to inflammatory vasodilation. Significant, positive correlation coefficients were found between error rates on the Inhibition condition of the visuomotor learning task and CBV values in occipital and periventricular NAWM bilaterally and both thalami (ranging between r=.52 and r=.62). On the Set Shifting condition of the respective task , significant positive associations were found between error rates and CBV values in the semioval center and periventricular NAWM bilaterally (ranged between r=.51 and r=.64) . CONCLUSION Regional perfusion changes, probably associated with active inflammatory processes in brain tissue, may be detrimental for simple executive functions, including inhibition ability and cognitive flexibility, in patients with CIS. Keywords Clinically isolated syndrome, perfusion MRI, executive function

Neuroradiology (2013) 55 (Suppl 1):S15–S159 S.18.06 GLUCOSE METABOLISM IN ADULT-ONSET AUTOSOMAL DOMINANT LEUKODYSTROPHY (ADLD) WITH AUTONOMIC SYMPTOMS J. Finnsson1, I. Savitcheva2, M. Lubberink4, A. Melberg3, R. Raininko1 1

Department of Radiology, Uppsala University, Uppsala, Sweden, Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm, Sweden, 3Department of Neuroscience/Neurology, Uppsala University, Uppsala, Sweden, 4Department of Nuclear Medicine & PET, Uppsala University, Uppsala, Sweden 2

INTRODUCTION Adult onset autosomal dominant leukodystrophy (ADLD) with autonomic symptoms is a rare genetic disease debuting in the 5th decade having a slowly progressive clinical course. Patients initially present autonomic symptoms and later progress to exhibit symptoms from cerebellar and corticospinal tracts. The MRI findings are nearly pathognomonic with extensive T2 hyperintensities throughout the supratentorial white matter though sparing a zone periventricularly. Very few leukodystrophy patients have been studied with positron emission tomography (PET) previously and their general appearance on this modality is not known. MATERIALS AND METHODS We recruited five subjects [median age 56, range 48–59 years] with genetic linkage to the disease and exhibiting extensive MRI changes in cerebral cerebral white matter, cerebellar peduncles and in the entire pyramidal tract. Five age-matched healthy controls were also included. All subjects and controls underwent dynamic 18 F-fluorodeoxyglucose (FDG) PET of the brain to quantitatively assess glucose metabolism. Glucose metabolic rate images were segmented into 46 regions of interest and glucose metabolism in subjects and controls was compared using Mann–Whitney tests. RESULTS Glucose metabolism was significantly and consistently approximately 20 % lower in all of the examined grey matter regions of interest in ADLD subjects compared to controls (29 μmol/g/min vs. 36 μmol/g/min, p=0.02). This difference was most pronounced in the cerebellum (29 %, p=0.01) and caudate nuclei (35 %, p=0.02). CONCLUSION The low general glucose metabolism throughout the brain is somewhat curious as most of the subjects had only mild symptoms. The even lower metabolism in the cerebellum is more consistent with the symptomatology of the patients. Keywords PET, leukodystrophy, MRI S.18.07 SIGNAL INTENSITY CHANGES IN MEDIAL TEMPORAL LOBE STRUCTURES IN ALZHEIMER DISEASE AND NORMAL AGING AND THEIR CORRELATION WITH ATROPHY AND CLINICAL MEASURES M. Martucci1, J. Alonso1, J. Corral1, D. Pareto1, X. Gurí1, A. Palasi2, F. Pujadas2, C. Auger1, A. Rovira1 1 MR Unit, Radiology Department, Vall d´Hebron University Hospital, Barcelona, Spain, 2Neurology Department, Vall d´Hebron University Hospital, Barcelona, Spain

PURPOSE To evaluate signal intensity (SI) changes on T2-FLAIR sequences in the hippocampi and adjacent subcortical white matter in patients with Alzheimer disease (AD) compared to elderly controls, in order to find potential correlation between SI changes, medial temporal lobe atrophy (MTA) and clinical measures.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS We retrospectively evaluated already acquired clinical and magnetic resonance imaging (MRI) data of 27 patients with AD and 19 elderly healthy controls. For each participant we performed a quantitative analysis of T2 SI of both hippocampi and subcortical white matter, using the head of the caudate nucleus to ensure the quantitative comparison. Relative SI of both hippocampi (rSIh) and subcortical white matter (rSIwm) were obtained. A qualitative evaluation was also made, blinded to the clinical status of the patient, in order to assess: - MTA, according to the Scheltens visual rating score - visual SI changes of hippocampi (H) and subcortical white matter (SWM), each side independently, compared to homolateral caudate nucleus and hippocampi, respectively. For each subject a Mini-Mental State Examination test (MMSE) and Clinical Dementia Rating scale (CDR) were obtained. Statistical analysis evaluated differences between patients and controls for the different MRI variables and correlations between clinical and MRI variables. RESULTS All quantitative and qualitative analysis showed significant differences between patients and controls (p<0.05). The group of patients presented significant correlations between MTA and visual SI changes of H (right: rho=0.57, p=0.002; left: rho=0.44, p=0.02) and SWM (right: rho=0.7, p<0.001; left: rho=0.45, p=0.02), each side evaluated independently. Visual SI changes of SWM also correlated with rSIwm (right: rho=0.41, p=0.03; left: rho=0.39, p=0.04). MMSE and CDR did not show significant correlation with MTA, visual SI changes and quantitative T2 SI evaluation. CONCLUSION There is a correlation between qualitative SI changes of the hippocampi and subcortical white matter and medial temporal lobe atrophy. Moreover, there is a correlation between qualitative and quantitative signal intensities of the SWM. This result point out to the interest in the radiological evaluation of the SWM for the assessment of AD patients. Keywords Alzheimer disease,T2/FLAIR signal changes, medial temporal lobe atrophy

S37 decrease, 10 entered the 2nd one (SG2) with activation increase. During the relapse DTI values in SG1 differed from the CG in medial lemniscuses, corticospinal tract (CST) on the internal capsules level bilaterally and in the motor area of corpus callosum (MACC), in SG2 – in palsy corresponding CST on the pons level, on the internal capsules level bilaterally and also in the MACC. All patients had increased NHPT performance time in comparison with CG and non-palsy hand. Clinical recovery in three months was also characterized by NHPT performance time decrease in both subgroups, but more significant in SG2, which differed from SG1 (Mann– Whitney U-test,p < 0,05), and was associated with significant changes of DTI values in MACC in SG2 (Wilcoxon matched pairs test,p<0,05), which became comparable with the CG. Positive correlation was revealed between NHPT performance time and radial diffusivity in SG2 (r = 0,71, Spearman’s rho). There was also SM1 activation decrease to CG level in SG2, while in SG1 there was no significant DTI values changes and SM1 activation remained decreased. CONCLUSION Clinical recovery in RRMS is associated with heterogeneous structural and functional changes, probably depending on initially different pathologic mechanisms. Better clinical outcome in RRMS patients after the relapse with motor disorders is associated with the recovery of DTI values in MACC and increased cortical activation during the relapse. Keywords Multiple sclerosis, diffusion-tensor imaging, functional MRI S.18.09 THE TIMELINE OF MEDIAL TEMPORAL LOBE ATROPHY DEPENDS ON THE CLINICAL SUBTYPE OF MULTIPLE SCLEROSIS - A VOXEL BASED MORPHOMETRY STUDY L. Kozák1, A. Iljicsov2, M. Simó2, D. Bereczki2, G. Rudas1, P. Barsi1 1

Semmelweis University, MR Research Center, Budapest, Hungary, Semmelweis University, Department of Neurology, Budapest, Hungary 2

S.18.08 STRUCTURAL AND FUNCTIONAL CHANGES IN MULTIPLE SCLEROSIS PATIENTS DURING THE RELAPSE WITH MOTOR DISORDERS AND IN THE FOLLOW-UP S. Kulikova, V. Bryukhov, A. Peresedova, O. Trifonova, M. Krotenkova, I. Zavalishin Research Center of Neurology RAMS, Moscow, Russia PURPOSE To investigate structural and functional features of motor disorders in relapse-remitting multiple sclerosis (RRMS) patients during the relapse and in the follow-up. MATERIALS AND METHODS Data were acquired from 25 RRMS patients, all right-handed, age ranged 19–50, during relapse characterized by unilateral light hand palsy and in three months during persistent remission. All patients underwent full neurological examination, including nine-hole peg test (NHPT). Magnetic resonance imaging (MRI) was performed on 1.5 T scanner; scanning protocol included functional MRI (fMRI) using simple movement paradigm and diffusion tensor imaging (DTI) sequences with regions of interest analysis. 11 age-matched healthy controls entered the control group (CG). RESULTS All patients were divided into two subgroups accordingly to primary sensorimotor cortex (SM1) reorganization pattern during the relapse: 15 entered the 1st subgroup (SG1) with activation

PURPOSE Converging evidence suggests that temporal lobe volume loss is associated with severity of disability and cognitive decline in multiple sclerosis (MS). We showed previously that lesion load in the temporal lobes is associated with the subtype of MS. Here, we aimed to investigate whether the volumetric loss of temporal gray matter (GM) depends on the clinical course of MS. METHODS Contrast-enhanced 3D-GRE-T1W images of 46 patients (32 females, mean age: 36.2±8.7 yrs, mean disease duration: 57.6±50.3 months) acquired on a 3 T Philips Achieva scanner were retrospectively analyzed. Seven patient had clinically isolated syndrome (CIS), 19 relapsing-remitting (RR), 9 clinically benign RR (RR-B), 7 primary progressive (PP), and 5 secondary progressive (SP) disease course. The mean expanded disability status scale (EDSS) was 1.5±1.8. Voxel based morphometry was performed using the VBM8 (http:// dbm.neuro.uni-jena.de/vbm8/) extension of the SPM8 package (http://www.fil.ion.ucl.ac.uk/spm/). Briefly, GM compartments were segmented and normalized to MNI space with intensity modulation, thus allowing for comparing absolute amount of tissue corrected for individual brain sizes. Between-group differences were assessed using one-way ANOVAs modeling interactions with EDSS or disease duration; age and gender were considered nuisance variables. Statistical parametric maps (SPM) were thresholded at p<0.001 uncorrected, with a cluster-size threshold of 72 voxels (~250 mm3).

S38 RESULTS Both EDSS score and disease duration had significant strong positive correlation across groups (r=0.52, p<0.0001), thus SPMs were also highly similar; therefore we only show results with respect to disease duration. Significant between-group differences were found in the GM volume vs. disease duration relationship in the medial temporal lobes, insular cortices, and the superior temporal gyri bilaterally, and in the left temporal pole, and right anterior cingulate cortex. The PP subgroup had the most prominent deterioration in the middle temporal and insular cortices, while superior temporal gyri were more affected in the RR, RR-B and SP groups. CONCLUSIONS There is a differential involvement of temporal lobes, insulae, etc. depending on the subtype of MS. The cross-sectional nature of our results limits the generalizability of our findings; however a further longitudinal investigation may overcome this limitation and could help elucidating the relationship of disease course and temporal lobe involvement. Keywords Multiple sclerosis, voxel based morphometry, temporal lobe SUNDAY, SEPTEMBER 29, 2013 – Room HZ 5 16:00–18:00 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - INTERVENTIONAL AVM AND AVF S.19.01 BRAIN ARTERIOVENOUS MALFORMATION TREATMENT BY VENOUS APPROACH S. Saleme, D. Ayoub, S. Ponomarjova, J.A. Mejia Nunez, T. Dinh, C. Mounayer CHU de Limoges, Department of Neuroradiology, Limoges, France PURPOSE We report our experience with the endovascular treatment of brain arteriovenous malformations (BAVMs) by venous approach. MATERIAL AND METHODS From February 2008 to April 2013 a total of 10 BAVMs have been treated by Onyx by venous approach. This technique has been chosen when there were no other therapeutic options for the treatment of ruptured BAVMs with a small nidus and, for most cases (8/10, 80 %) with deep venous drainage. Patients consisted of 6 female and 4 male with an average of 39,5 years old(12–57 years). In 50,0 % (5/10) of cases the BAVM was treated by venous approach alone and in the other50,0 % (5/10) by both arterial and venous approaches. RESULTS Complete exclusion of the nidus was obtained in L’exclusion complète du nidus a été obtenue en 90 % (9/10) of cases. We had one complication (1/10, 10 %) related to the procedure due to venous perforation during microcatheterism wich was immediately controlled by injection of Onyx resulting in intraventricular hemorrhage with no clinical consequence. All patients remained clinically stable without change of mRS. CONCLUSION The venous approach is a safe and efficient technique in the treatment of ruptured BAVMs when there are no other therapeutique options and when certain anatomic considerations are respected. Keywords Brain AVM, onyx, venous approach S.19.02 ONYX EMBOLIZATION OF CEREBRAL ARTERIOVENOUS MALFORMATIONS BY MENINGEAL ARTERY APPROACH H. Nordmeyer, M. Heddier, M. Stauder, P. Schoss, P. Stracke, R. Chapot Alfried Krupp Hospital, Essen, Germany

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Meningeal feeders are frequently seen in patients harbouring an arteriovenous malformation of the brain (AVM). Despite the high prevalence of meningeal blood supply to BAVM, embolization is routinely performed via pial arteries. We report on our experience in AVM treatment by selective Onyx embolization of meningeal arteries regarding the degree of occlusion compared to cerebral artery approach and procedure related complications. METHODS We retrospectively reviewed all patients treated for an AVM from January 2007 until December 2009 using Onyx as an embolization agent. All AVM were characterized according to the Spetzler Martin grading scale. Angiographic images and intervention reports were assessed for the presence of meningeal feeding arteries, accessed feeders and the amount of Onyx injected per feeding artery. Technical adverse events were recorded as well as clinical deterioration of the patient after the procedure, including a three years follow-up. Post procedure MRI images were reviewed for the presence of cerebral ischemia or hemorrhage. RESULTS 340 endovascular procedures were achieved in 140 patients (64 female, 76 male, mean age 39 years) within this 3 years time period. According to the Spetzler-Martin Grading Scale, there were 21 % grade I-II, 21 % as grade III and 58 % as grade IV-V. Meningeal supply was found in 33 patients with a total number of 42 meningeal arteries that were selectively catheterized and embolized. The meningeal arteries were the middle meningeal artery (n=33), the posterior meningeal artery (n=5), 3 occipital arteries and 1 superficial temporal artery. The median amount of Onyx injected per meningeal feeder was 4.82 ml (range 1 – 29 ml) compared to 1.79 ml (range 1 – 36 ml) in cerebral (pial) artery approach. Meningeal artery treatment led to one microcatheter rupture without clinical sequelae. Hemorrhage occurred in one patient with a previous hemorrhage after embolization. We did not observe severe ischemic complications either clinically or on imaging studies after meningeal artery Onyx injection. CONCLUSION Onyx embolization of meningeal feeding arteries is safe and effective in AVM embolization. It enables to increase the occlusion rate after embolization and to enlarge the range of AVMs that can be cured by embolization alone or complementary to surgery or radiosurgery. Keywords AVM, embolization, meniningeal S.19.03 THE RADIOGRAPHIC OUTCOME OF SILENT MICROEMBOLISM ON DIFFUSION-WEIGHTED IMAGING IS IDENTICAL BETWEEN MICROSURGICAL CLIPPING AND ENDOVASCULAR COILING T. Matsushige1, Y. Kiura1, S. Sakamoto1, T. Okazaki1, K. Shinagawa1, N. Ichinose1, M. Takasu2, Y. Akiyama2, K. Kurisu1 1 Department of Neurosurgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan, 2Department of Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan

PURPOSE The aim of this study was to compare the radiographic outcome of periprocedural silent microembolism in microsurgical clipping and endovascular coiling of unruptured cerebral aneurysm. METHODS We examined 80 consecutive patients with unruptured cerebral aneurysms treated with 39 in clipping and 41 in coiling. We assessed the characteristics of 113 high signal spots on DWI at MRI after the procedures with parameters (location, volume, values of the apparent diffusion coefficient: ADC) of each spot and evaluated their radiographic outcome on conventional CT or MRI at follow-up. To compare differences between two groups, we used Fisher exact test for categorical factors and the Mann–Whitney U-test for quantitative variables. Statistical significance was assigned when p<0.05.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS The positivity of DWI was higher in coiling (65.6 %) than in clipping (15.4 %, p < 0.0001). The value of ADC was larger in coiling (0.762 ± 0.147 × 10- 3 mm 2 /s) than in clipping (0.658 ± 0.151 × 10-3 mm2/s, p=0.0179) and the volume of high signal spots was smaller in coiling (0.098 ± 0.064 cm 3 ) than in clipping (0.198±0.156 cm3, p=0.0015). The coiling had significantly better radiographic outcome without corresponding signal change at follow up (coiling: 13.3 % and clipping: 63.6 %, p=0.0001). Hence the frequency of periprocedural silent brain infarction at follow up was identical between coiling and clipping (coiling: 15.4 % and clipping: 10.0 %, p = 0.5179). The presumable causes of microembolism in clipping were from the plaque around the aneurysmal neck in 3 and perforators obstruction in 2, whereas one in coiling was invisible thrombosis. CONCLUSIONS A number of high signal spots on DWI in endovascular coiling did not correspond to brain infarction. Considering radiographic outcome of silent microembolism, thromboembolic risk was thought to be equivalent in comparison between microsurgical clipping and endovascular coiling. Keywords Diffusion-weighted imaging, microsurgical clipping, endovascular coiling S.19.04 COIL EMBOLIZATION OF ANEURYSMS INCORPORATING A BRANCH INTO THE SAC, SAFETY, DURABILITY, SINGLE CENTER EXPERIENCE O. Mansour1,2,3, M. Megahed1 1

Alexandria University, Interventional Neurology Division, Alexandria, Egypt, 2 Tanta University, Neuroradiology Center, Tanta, Egypt, 3 Freiburg Uniklinkum, Eurozentrum, Neuroradiologie Abt., Freiburg, Germany BACKGROUND One of the true challenge for endovascular specialist in treating aneurysms is the aneurysm with a branch incorporated into the sac ,because of the concern for occlusion of that branch artery. The aim of this study is to evaluate the feasibility, safety , techniques, and midterm clinical and angiographic outcomes of coiling for aneurysms with a branch incorporated into the sac. MATERIALS AND METHODS The medical records and radiologic studies of 49 patients with 59 aneurysms having a branch incorporated into the sac (26 ruptured, 33 unruptured) were retrospectively reviewed and evaluated. RESULTS Coiling was accomplished in 59 aneurysms in 49. The aneurysms were treated by using the following techniques: single-catheter (n=17), multicatheter (n=22), balloon-remodeling (n=7), stent-assisted coiling (n=6), and combined (n=7). Postembolization angiography revealed the following: near-complete occlusion in 50 (84.7 %), remnant neck in 4 (6.8 %), and incomplete occlusion in 5 (8.5.1 %) aneurysms. Procedure-related permanent morbidity and mortality rates were 6.1 % (3/49) and 0 %, respectively. All patients with unruptured aneurysms had a modified Rankin Scale (mRS) score of 0, except for 1 patient who had an mRS score of 3. Of the 26 patients with ruptured aneurysms, 20 had favorable outcome (mRS 0–2) but 6 had poor outcome (mRS 3–6). Follow-up angiography was available at least once at 6–50 months (mean, 15 months) in 55 aneurysms (93.2 %), of which 45 showed stable or improved occlusion; 4, minor recurrences; and 6, major recurrences. All 6 major recurrent aneurysms were retreated without complication by using a single-catheter (n=1), multicatheter (n=2), or balloonassisted technique (n=3).

S39 CONCLUSIONS With appropriate techniques, most aneurysms with a branch incorporated into the sac could be safely treated by coiling, with acceptable outcomes. Keywords Aneurysm, sac incorporated branch, coiling S.19.05 HYPOGLOSSAL CANAL DAVF: SYSTEMATIC REVIEW ON IMAGING ANATOMY, CLINICAL FINDINGS, AND ENDOVASCULAR MANAGEMENT S. Meckel1, S. El Sharifi1, C. Hader1,2, T.P. Singh3, D. San Millán Ruíz4, B. Spittau5 1

University Hospital Freiburg, Neuroradiology, Freiburg, Germany, Cantonal Hospital St. Gallen, Neuroradiology, St. Gallen, Switzerland, 3 Sir Charles Gairdner Hospital, Neurological Intervention and Imaging Service of Western Australia (NIISWA), Perth, Australia, 4Hospital of Sion, Valais, Neuroradiology Unit, Sion, Switzerland, 5University of Freiburg, Institute for Anatomy and Cell Biology, Department of Molecular Embryology, Freiburg, Germany 2

PURPOSE DAVF of hypoglossal canal is a rare type of cranial DAVF exhibiting complex angiographic anatomy due to variable venous drainage pathways. Hitherto, these fistulas have been referred to as various entities (e.g. marginal sinus DAVF) that were solely described in case reports or small series. We aimed to provide a comprehensive review on these DAVFs and associated venous anatomy. METHODS Craniocervical venous anatomy including multiple variable anastomoses between condylar veins, vertebral venous plexus, jugular system/dural sinuses, and perimedullary veins was reviewed. In systematic PUBMED research, all relevant publications on hypoglossal canal DAVFs were identified. Including 4 own cases, 72 DAVFs were analysed for clinical and angiographic findings, therapeutic strategies, complications, and outcome. RESULTS DAVFs were composed of fistulous pouch involving anterior condylar complex/vein with variable intraosseous component. 3D angiographic imaging enabled precise description in many cases. Fistulas with antegrade drainage usually presented with pulse-synchronous tinnitus (87.8 %). Ocular symptoms were second most common presentation (27.3 %) associated with reflux into IPS/CS/superior ophthalmic vein (24.4 %). Hypoglossal nerve palsy was presenting finding in 13.6 %. Rarely, aggressive fistulas with exclusive cortical (3 %)/perimedullary (3 %) drainage presented with hemorrhage or cervical myelopathy. Transvenous embolization (TVE) was performed in 70.8 % with low permanent morbidity (3.9 %), and total occlusion in 93.6 %. Understanding of complex venous anatomy was crucial for planning alternative approaches if standard transjugular access was impossible. Transarterial embolization (TAE) alone (15.3 %) and surgical disconnection of fistulas (5.6 %) was only performed in exclusively cortical/perimedullary draining, or poorly accessible lesions. Permanent morbidity in TAE using liquid embolic agents was 28.6 % related to lower cranial nerve injuries. Spontaneous occlusion of fistulas occurred in 8.3 %. CONCLUSIONS Hypoglossal canal DAVFs are unique due to involvement of complex venous skull base anatomy: 3 distinct types of venous drainage in association with clinical symptoms may be observed Thereby, retrograde orbital venous flow occurs second most commonly mimicking CS fistulas. TVE is treatment of primary choice demonstrating high safety and efficacy. TAE and/or surgery should be reserved for DAVFs with

S40 exclusive cortical/perimedullary drainage or if TVE is not possible. A conservative strategy may be followed in solely antegrade draining fistulas. Keywords Dural arteriovenous fistula, hypoglossal canal, venous anastomosis S.19.06 CLINICAL EXPERIENCE AND RESULTS IN A SERIES OF 27 ANEURYSMS TREATED WITH PENUMBRA PC 400 COILS J. Massó Romero, A. Lüttich Uroz, J. Larrea Peña, E. Pardo Zudaire, A. Masso Ordiozola, S. Cervantes Ibañez Hospital Donostia San Sebastián Servicio de Neuro Radiologia Paseo dr Begiristain Donostia, San Sebastián, Spain PURPOSE Penumbra PC 400 coils have 400 % more volume compared to conventional 0.010 coils of the same length. In our work we present the characteristics, device handling issues and advantages based on results from post procedural and follow-ups, including cost effectiveness of this product. METHODS We treated 27 aneurysms in 26 patients with the following locations: 2 in the ICA, 3 in the basilar tip, 9 in the ophthalmic, 5 in the posterior communicating, 5 in the middle cerebral arteries and 3 in other locations. We considered three groups in relation to the size: Group 1 up to 7 mm in maximum diameter (22 %); Group 2 from 7 to 15 mm (63 %); Group 3 more than 15 mm (15 %). In total, 74 % of the aneurysms had a neck greater than 4 mm. In 44 % of cases, we used PC 400 coils without any additional devices. In most cases, a volumetric estimation and packing density calculation were attained. In 48 % of cases, the clinical presentation was incidental, 44 % HSA, 8 % other. To assess the level of occlusion, we used the modified Raymond scale. We comprehensively evaluated the access devices and additional devices used. RESULTS We have evaluated the clinical outcomes at 48 hours and 30 days according to the modified Rankin scale, and in 23 cases the mRS score was 0 at 30 days. No severe complications were found. In 84 % of cases, complete occlusion was noted, and in the cases without complete occlusion, we observed no significant changes in aneurysm appearance. In our analysis of cost/effectiveness we agree with other work previously presented on the efficiency of this device. CONCLUSIONS The new microcatheter PX SLIM has provided a significant improvement in navigability, trackability and intra-aneurysmal access. In every case where 35 % packing density was achieved, we observed a durable complete occlusion. All cases in which we combined this device with a flow diverter stent presented a complete occlusion in the first attempt. Use of the access device NeuronMAX significantly facilitated the use of additional devices. The level of safety and ease of use are not determined by the aneurysm size. Keywords Cerebral aneurysm, coil embolization, clinical outcome S.19.07 VENO-SINUS HEMODYNAMICS OF DAVF: THE CLINICAL IMPLICATION OF QUANTITATIVE DSA W. Guo1, C.J. Lin1,2, S.C. Hung1,2, F.C. Chang1,2, W.F. Chu1, H.M. Wu1,2, C.B. Luo1,2, W.Y. Chung1,3 1 Taipei Veterans General Hospital, Department of Radiology, Taipei, Taiwan, 2School of Medicine, National Yang-Ming University, Taipei, Taiwan, 3Taipei Veterans General Hospital, Department of Neurosurgery, Taipei, Taiwan

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Dural arteriovenous fistula (DAVF) is associated with dynamically changing hemodynamics and clinical manifestation. A full understanding of the hemodynamics secures a proper management. The current study presents our experience in applying quantitative x-ray digital subtractive angiography (QDSA) in evaluating the hemodynamics of DAVF and the clinical implication. METHODS 23 patients (M/F=11/12, age=60, 27–88 y/o) with DAVF involved transverse-sigmoid sinuses (Cognard type I=11, IIa=6, IIa+b=6) and treated by Gamma Knife® radiosurgery in a 2-year time were recruited. All treatments were guided by integrating stereotactic DSA and MRI. All stereotactic MRI were performed on a 1.5 T MR scanner and all stereotactic DSA on a biplane angiosuite (AXIOM-Artis Zee®, Siemens Healthcare, Forchheim, Germany) with a same imaging protocol. Colorcoded QDSA by using Syngo iFlow® (version VB15, Siemens Healthcare, Forchheim, Germany) was employed to evaluate the hemodynamics of the DAVF focusing on the intracranial circulation time, waveforms of the time-density curves and morphology of sinuses. 34 patients with normal intracranial hemodynamics served as the control. RESULTS The circulation time of DAVF measured at the venous outlets was shorter than the normal control (0.75±1.1 versus 6.81±1.25 second, p<0.05). Multiple-peak waveforms at the arterialized draining sinus of DAVF were observed in 15 cases. The waveforms indicated that the arterialized sinus drained not only the trans-fistula flows of DAVF as the first pass but also the venous return from other unaffected tissues as the second or later passes. One DAVF drained into a stenotic sinus; the stenosis and clinical status deteriorated after the DAVF became partly cured. For DAVF associated with veno-sinus outlet stenosis, the transfistula flows might serve as the “driving force” to keep the venous flow moving. It would be physiologically favorable to open the stenotic outlet before closing the DAVF when treat a DAVF with veno-sinus outlet stenosis. CONCLUSIONS Both hemodynamics of arterial and venous components should be globally taken care of when deal with intracranial DAVF. The global consideration is more important when a DAVF is associated with sinovenous stenosis or occlusion. QDSA opens another window for refining the therapeutic strategy of DAVF. Keywords DSA, DAVF, hemodynamics S.19.08 RESOLUTIVE ENDOVASCULAR TREATMENT OF CAROTIDCAVERNOUS FISTULA WITH DETACHABLE BALLONS J. Figueroa, A. Martinez-Ponce De Leon University Hospital Jose Eleuterio González UANL, Neurosurgery Service and Endovascular Neurological Therapy, Monterrey, Mexico PURPOSE The cavernous sinus (CS) is a complex structure that has been studied since decades. An abnormal communication between the Carotid Artery and the CS is known as Carotid-Cavernous Fistula (CCF) which diagnosis and treatment is a challenge. The shunt location, flow type and its etiology allows its appropriate classification. The endovascular treatment with balloons is used since the 70's by Servinenko. In this series, we use detachable ballons (DB) for a resolutive treatment of the CCF. METHODS We made a retrospective study from March 2007 to March 2013 at the Neurosurgery Service and Endovascular Neurological Therapy of the University Hospital “Jose Eleuterio Gonzalez” UANL in Monterrey Mexico. We enrolled patients with direct CCF. We examined the demographic, clinic and angiographic features.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS We included 38 patients, 8 women (21.05 %), 30 men (78.95 %). The most common etiology was a traumatic brain injury (TBI) in 26 patients (68 %). The bruit and exophthalmos were found in 84.21 % and 81.57 %, respectively. A complete embolization of the CCF was done on 97 % of the patients on the first procedure and 100 % in the second one; all succesfull results were confirmed with angiographic monitoring at 6 months. We report 4 complications inherent to the procedure and no decease were presented. A positive correlation between the safety and effectiveness was found with the endovascular usage of DB in patients with direct CCF. CONCLUSIONS In our experience, detachable ballons are an effective and safety endovascular alternative in the treatment of direct Carotid-cavernous fistula. Keywords Carotid-cavernous fistula, cavernous sinus, angiography S.19.09 SAFETYAND EFFICACY OFA NEW DEVICE FORTHE TREATMENT OF WIDE NECK BIFURCATION ANEURYSMS (PCONUS) – PRELIMINARY EXPERIENCE

S41 CONCLUSION The pCONus device allows controlled coil occlusion of wide neck bifurcation aneurysms, both ruptured and unruptured. Major complications are rare. Keywords Wide neck, bifurcation, aneurysms SUNDAY, SEPTEMBER 29, 2013 – ROOM HZ 4 16:00–18:00PARALLELSCIENTIFICSESSIONWITHINTRODUCTORY INVITED PRESENTATION - SPINAL IMAGING S.20.01 WHAT IS MISSED WHEN REPORTING MRI LUMBAR SPINES - MOST COMMON FALSE NEGATIVE ERRORS AND HOW TO LOWER THEIR INCIDENCE C. Schorlemmer, E. Thimansson Telemedicine Clinic, Barcelona, Spain

M. Aguilar Pérez1, W. Kurre1, S. Felber2, E. Donauer3, N. Hopf4, H. Bäzner5, H. Henkes1 1

Klinikum Stuttgart, Department of Neuroradiology, Stuttgart, Germany, Stiftungsklinikum Mittelrhein, Department of Neuroradiology, Koblenz, Germany, 3Mediclin Krankenhaus, Department of Neurosurgery, Plau Am See, Germany, 4Klinikum Stuttgart, Department of Neurosurgery, Stuttgart, Germany, 5Klinikum Stuttgart, Department of Neurology, Stuttgart, Germany 2

PURPOSE Wide neck bifurcation aneurysms (WNBA) are considered to belong to the subgroup of aneurysms with increased treatment difficulty and risks. The simultaneous use of two or more microcatheters and the use of one or two compliant balloons are known techniques for the treatment of these aneurysms. Also the use of intracranial self-expanding stents to create an artificial border between vessel and aneurysm has shown to be a safe and efficacious option. pCONus is a self-expanding, completely retrievable, electrolytically detachable device with a proximal shaft and 4 distal petals and with a nylon cross in the distal end of the shaft. The device is made to bridge the orifice of WNBA in order to allow better control of the coil occlusion. It combines functional elements of “waffle cone” stent deployment and the no longer available TriSpan Neck Bridging Device. The purpose of this study was to evaluate the safety and efficacy of this new device for the treatment of intracranial wideneck bifurcation aneurysms. METHODS 21 consecutive patients underwent an endovascular treatment of intracranial WNBA using the pCONus device between February, 2012 and May, 2013. Target vessels included the anterior circulation in 17 (81 %) and the posterior circulation in 4 (19 %). 7 patients were treated in the setting of acute subarachnoid hemorrhage (33.3 %) and 5 of the aneurysms showed reperfusion after previous coil occlusion (23.8 %). RESULTS No technical failure was encountered. Rupture did not occur during any of the procedures. No premedication was used in the patients with subarachnoid hemorrhage. Acute thrombi formation was observed in only one patient (4.8 %), which resolved after administration a body weight adapted bolus dose of eptifibatide (Integrilin). After the initial embolization procedure, total occlusion was achieved in 6 (28.6 %) patients and a neck remnant was evident in 7 (33.3 %). Follow-up angiography 3 months after the treatment was available in 13 patients and demonstrated complete occlusion in 6 (46.2 %). Evident coil compaction requiring second treatment was observed in two patients (15.4 %). pCONus also assisted re-coiling without major complication.

PURPOSE Measure the prevalence and identify the most common types of false negative errors of MRI lumbar spine reports and suggest specific actions to be undertaken to lower their incidence. METHODS As part of the quality assurance activity in our radiology department, we second read systematically and on a routine basis a significant percentage of all our radiology reports since 2004. The resulting discrepancies between the first and the second read are scored according to a 5-point scale. 5, full agreement; 4, clinically insignificant discrepancy; 3, possible clinically significant discrepancy; 2, probable clinically significant discrepancy; and 1, almost certain clinically significant discrepancy. Out of the collected discrepancy data, we have specifically extracted the false negative errors of the reports of 5947 double read outpatient MR lumbar spines done between January 2009 and April 2012. 20 radiologists highly experienced in MRI lumbar spine reporting have been included in the study. RESULTS The discrepancy analysis revealed a prevalence of 2.3 % of significant false negative errors (discrepancy level 3 or below) and 31 different false negative error types. The 3 most common false negative errors involving the spine were missed disc hernias (28,5 %), missed transitional vertebras (12 %) and missed spondylolysis (7 %). The 2 most common false negative errors outside the spine were missed mass lesions of the pelvis (4.5 %) and missed abnormalities of the kidneys (4 %). CONCLUSIONS Out of a total number of 31 false negative error types of 5947 MRI lumbar spine reports the 5 most common represented almost 60 %. Specific recommendations related to structured image analysis, structured reporting and RIS tools are given to lower their incidence. Keywords MRI lumbar spine, radiology report, false negative error S.20.02 TUBERCULOUS SPINE - VARIED PRESENTATION U. Rashid Post Graduate Medical Institute, Lahore, Pakistan The aim of the study is to estimate the incidence and types of spinal tuberculosis referred to our department for diagnosis. Majority of patients presented with backache and various neurological symptoms depending upon level of cord compression.

S42 MATERIAL AND METHODS 2000 patients were selected by convenience sampling from January 2006 to September 2010. Study design was descriptive and among two thousand mostly unknown cases without evidence of symptoms of systemic tuberculosis (1080 males & 920 females). MRI without & with IV Contrast, CECT with MPR, and in some cases, not fit for MRI, CT Myelography were performed. In a few selected patients’ cases, MR Spectrograms were also obtained to rule out the possibility of metastasis. MRI remained the choice of imaging and was performed on 1.5 tesla Phillips MRI at Lahore General Hospital, PGMI, Lahore, Pakistan. Histopathological biopsies were available in 240 cases. RESULTS Out of 2000 cases of tuberculous spine 1080 (54 %) were male and 920 (46 %) were female. Their age ranges from 8 – 60 years. About 90 % of patients were below the age of 40 years. Peak age among the males and females were 20–29 years and 14–35 years respectively. The most common site of involvement was dorsal spine (45 %) followed by lumbo-sacral spine (33 %), cervical spine (10 %) and at multiple levels (12 %). Biopsies were done in 240 (12 %) cases. On MRI vertebral end plate destruction and reduced disc space are the commonest in all the biopsied cases (100 %). Among those at multiple levels, all the 240 cases (100 %) showed the involvement of dorsal spine. 88 % typical cases were further classified according to type of presentation: central (22 %), marginal (71 %) & peripheral (7 %). Incidence of atypical cases was 12 %. CONCLUSION Young males belonging to age group 20–29 years are more affected and the most common site is dorsal spine (45 %). MRI is an excellent tool to investigate the diseases of spine particularly tuberculous spine. However, an atypical radiological presentation of spinal tuberculosis presents a challenge for an appropriate diagnosis and early treatment, due to atypical clinical and radiological features. Spinal tuberculosis should always be suspected when radiographs demonstrate a destructive spinal process. Awareness and prompt management of TB spine will help in reducing the continuing morbidity of this disease. Keywords Tuberculous, central types, MRS S.20.03 DIFFUSION TENSOR IMAGING INDEXES CORRELATE WITH CONVENTIONAL MRI FOR LUMBAR INTERVERTEBRAL DISC DEGENERATION J. Puig1, G. Blasco1, J. Daunis-I-Estadella2, X. Molina1, C. Guergue1, S. Pedraza1 1

Department of Radiology (IDI), Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain, 2 Department of Computer Science , Applied Mathematics and Statistics, University of Girona, Girona, Spain PURPOSE Degeneration of the lumbar intervertebral discs (LIVD) is the most common condition that contributes to pain syndromes affecting the adult spine. The structure and composition of the annulus fibrosus and nucleus pulposus are important determinants of lumbar mechanical functions, and these parameters change with degeneration. Classically, LIVD degeneration has been assessed through qualitative differentiation between the nucleus pulposus and annulus fibrosus on T2-weighted imaging, based on water content. Newer, diffusion tensor imaging (DTI) enables quantitative assessment of LIVD, providing information on the microstructural status of tissue through anisotropic indexes that show the predominant direction and degree of diffusion of water. We investigated whether DTI metrics of LIVD correlate with visual grading of degeneration on T2-weighted imaging.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 MATERIAL AND METHODS 178 consecutive patients (82 women; age, 46±15 years) with low back pain underwent 1.5 T MRI including sagittal and axial T1- and T2weighted FSE and DTI sequences acquired in 15 directions. All imaging analyses focused on the L4-L5 discs. Quantitative evaluations of the annulus fibrosus and nucleus pulposus were based on fractional anisotropy (FA) values, mean diffusivity (MD), apparent diffusion coefficient (ADC), and T2 signal intensity (SI) on coregistered maps using multiple regions of interest (Olea Medical, Sphere, La Ciotat, France). The qualitative assessment categorized discs as normal (hyperintense), slightlymoderately degenerated (intermediate signal), and moderately-severely degenerated (hypointense) on T2-weighted images. Bulging and herniated discs were also recorded. RESULTS 62 (34.8 %) discs had normal T2-SI; 44 (27.7 %) were bulging and 41 (23 %) were herniated. Mean FA values tended to decrease significantly with degeneration (normal>bulging>herniated discs) (p=0.004). After adjusting for age, lower FA values on the annulus fibrosus significantly correlated with degenerative LIVD (p=0.011), with increased mean FA (p=0.002), with decreased mean ADC (p=0.001), and with decreased median MD (p=0.021). Decreased median T2-SI (p<0.001) on the nucleus pulposus correlated significantly with degenerative LIVD. CONCLUSIONS These preliminary findings suggest DTI is a potentially valuable noninvasive tool to quantitatively assess water diffusion anisotropy for characterizing LIVD degeneration. Quantitative imaging techniques like DTI metrics may help clinicians and researchers understand the development and clinical course of degenerative disc disease. Keywords Lumbar disc, diffusion tensor imaging, magnetic resonance imaging S.20.04 SAFETY ASPECT AND OUTCOME IN INTRATHECALLY APPLIED GADOLINIUM CONTAINING CONTRAST MEDIA FOR THE DIAGNOSIS OF INTRACRANIAL HYPOTENSION SYNDROME F. Donnerstag 1 , P. Raab 1 , E. Bültmann 1 , F. Götz 1 , R. Pul 2 , H. Lanfermann1 1

Institute of Diagnostic and Interventional Neuroradiology, Hannover Medical School, Hannover, Germany, 2Department of Neurology, Hannover Medical School, Hannover, Germany PURPOSE To prospectively evalutate on a 2 years basis the safety and outcome of patients with spontaneous intracranial hypotension syndrome (SIHS) due to cerebrospinal fluid (CSF) leaks which were diagnosed with intrathecal injection of gadolinium containing contrast media (GdCM) and treated with CT-targeted blood patch. METHODS From February 2009 until December 2012 8 women and 2 men were treated with orthostatic headache in our institution. All patients were contacted for 2 years concerning subjective well-being especially headaches or SIHS related symptoms until December 2012. All 10 patients were interviewed by telefone in 1, 3, 6, 12 and 24 months after they received the Gd-CM into the CSF. They were also asked for other complains which could be related to the intrathecally applied Gd-CM, especially new neurological deficits, seizure or signs of nephrogenic systemic fibrosis. RESULTS All patients but one had signs of CSF leakage in the cervical or upper thoracic spine, one women had an addional leak in the lumbar spine and were all treated with a single CT-guided blood patch. One women with SIHS longer then 2 years before treatment suffered of residual orthostatic headaches. In 1 women with marfan syndrome a new thoracic

Neuroradiology (2013) 55 (Suppl 1):S15–S159 dehiscence was successfully treated after first lumbar patch. Finally, a female patients with inital dural CSF leaks in cervical nerve roots had a relapse in the upper thoracic spine which could be treated successfully. Until the end of the questionaire in December 2012 all 10 patients tolerated well the intrathecally injected Gd-CM. All but one women with a long standing SIHS presented with a permanent relief of orthostatic headaches or other SIHS related affection of cranial nerves. CONCLUSION Intrathecally injected gadolinium containing contrast media seems to be safe and warranted a successful outcome on a 2 years basis in diagnosis and treatment of spontaneous intracranial hypotension syndrome. Further investigations with a greater number of patients are necessary to confirm the safety of intrathecally applied Gadolinium containing contrast medium. Keywords Intracranial hypotension, intrathecal gadolinium, outcome and safety S.20.05 DYNAMIC CONTRAST ENHANCEMENT MAGNETIC RESONANCE PERFUSION OF THE SPINAL CORD AND ADJACENT LESIONS V. Cuvinciuc1, M. Viallon2, F. Herrmann3, S. Haller1, M.I. Vargas1, K.O. Lovblad1 1

University Hospitals of Geneva, Imaging Department, Neuroradiology Unit, Geneva, Switzerland, 2University Hospitals of Geneva, Imaging Department, Radiology Unit, Geneva, Switzerland, 3University Hospitals of Geneva, Department of Internal Medecine, Rehabilitation and Geriatrics, Geneva, Switzerland PURPOSE Demonstrate the feasibility and clinical utility of dynamic contrast enhancement (DCE) magnetic resonance perfusion of the spinal cord and adjacent lesions. METHODS We have performed DCE perfusion in 26 patients with various enhancing medullary and extramedullary lesions, such as fibrillary astrocytoma, glioblastoma, hemangioblastomas, meningiomas, schwannomas, bone metastases and acute benign compression fractures. T1 mapping was based on two T1 acquisitions with 2 and 15 degrees flip angles. The dynamic acquisition was performed in a sagittal plane with a 3 mm thick T1 VIBE sequence and temporal resolution of 7.8 - 9.5 seconds on two MR machines, of 3 T and 1.5 T. 2D regions of interest were drawn within the normal appearing spinal cord (at least one vertebral body away from any abnormality) and within the enhancing lesion. The pharmacokinetic modeling (PKM) is based on a twocompartments model that allows for voxel-based calculation of permeability parameters (Ktrans, kep), leakage space (ve) and contrast volume within the region of interest (initial area under the curve - iAUC). RESULTS Within the normal-appearing spinal cord, PKM was correct in 78.30 % of the voxels acquired on 3 T and 42.17 % on 1.5 T (P<0.05). The correct modeling was more frequent in the cervical spinal cord (70.25 % on 1.5 T, 88.41 % on 3 T) then high dorsal spinal cord (33.99 % on 1.5 T, 73.33 % on 3 T) and low dorsal spinal cord (44.45 % on 1.5 T, 79.23 % on 3 T). The odds-radio of correct PKM, adjusted for spinal cord level, was 7.88 for 3 T compared to 1.5 T. The goodness of fit was computed with chi2 parameter; the values were significantly lower (better fit) for 3 T (mean 0.0332, standard deviation 0.0217) compared to 1.5 T (mean 0.0462, standard deviation 0.0380), P<0.0001. For meningiomas, mean Ktrans values of 0.134 min-1 are similar to literature data for head meningiomas. Schwannoma seems to have higher Ktrans values (mean 0.505 min-1). iAUC values are similar between schwannomas and meningiomas. Hemangioblastomas have highly elevated iAUC values (mean 41.764 mM x s), compatible with their hypervascularity.

S43 CONCLUSION These initial results show the feasibility and potential clinical utility of DCE-MR perfusion of the spinal cord and adjacent lesions. Keywords Dynamic contrast enhancement, spinal cord S.20.06 INITIAL EXPERIENCE WITH DOUBLE INVERSION RECOVERY IN THE DETECTION OF MULTIPLE SCLEROSIS LESIONS IN THE CERVICAL CORD: A COMPARISON WITH PROTON DENSITY WEIGHTED AND T2 WEIGHTED SEQUENCES AT 1.5 TESLA A. Chong, E. Roberts, R.V. Chandra, K. Chuah, S. Stuckey Monash Medical Centre, Melbourne, Australia PURPOSE Double inversion recovery (DIR) has been shown to be more sensitive than T2 turbo spin echo (TSE) and FLAIR for detection of multiple sclerosis (MS) lesions in the brain. However DIR sensitivity in the cervical cord remains unexplored. The cervical cord to C6 is routinely included as part of brain DIR imaging. We hypothesised that detection of cervical cord lesions on brain DIR may mitigate the need for dedicated cervical cord T2/PD imaging. The aim of the study was to compare cervical cord MS lesion detection and conspicuity on sagittal 1.5 T DIR brain to PD TSE and T2 TSE cervical cord imaging. METHODS 40 patients being treated or investigated for MS over a six-month period with brain and cervical cord MRI were included in this retrospective analysis. Sagittal DIR, PD TSE and T2 TSE images were acquired on a 1.5 T Siemens Magnetom Avanto MRI scanner. A head and neck matrix coil combination was utilised for brain DIR, which included the cervical cord to C6. A 4-channel neck matrix coil was employed for PD TSE and T2 TSE sequences. Two neuroradiologists identified MS lesions, with consensus agreement for single viewer lesions. Regions of interest were obtained within lesions using Osirix v3.0.2. Quantitative analysis comparing the normalised lesion-to-cord contrast ratio (LCCR) and the signal-to-noise ratio (SNR) for each sequence was performed using sample T-tests, where P>0.05 was considered statistically significant. RESULTS 81 cervical cord lesions were detected in 19 patients — 25 on DIR, 25 on T2 TSE and 31 on PD TSE. Five patients with positive T2 TSE scans had negative DIR imaging. Compared to PD and T2, DIR had greater LCCR (DIR 1.51±0.09 vs. PD TSE 0.26±0.02, P<0.0001; DIR vs. T2 TSE 0.30±0.03, P<0.0001), and higher SNR (DIR 126.90±5.94 vs. PD TSE 52.63±4.00, P<0.0001; DIR vs. T2 TSE 53.02±4.99, P<0.0001). CONCLUSIONS DIR detected lesions demonstrate superior contrast resolution and SNR compared to T2 TSE and PD TSE imaging. However multiple cervical cord lesions detected on T2 and/or PD are not detected on DIR brain imaging that includes the cervical cord. Dedicated T2 and/or PD cervical cord imaging should also be performed. Keywords DIR, multiple sclerosis, cervical cord S.20.07 UNDERSTANDING THE BAASTRUP'S DISEASE SPECTRUM: FROM KISSING SPINE TO INTERSPINOUS BURSITIS A. Bourgeois, A. Faulkner, J. Boyd, P. Campbell University of Tennessee Medical Center, Knoxville, TN, USA PURPOSE Baastrup’s disease refers to a spectrum of low-back pain derived from spinous process hypertrophy. As the normal spine ages, the spinous

S44 processes hypertrophy in a majority of patients. In a subset of these patients, repetitive mechanical friction produces degeneration of the interspinous ligament and a painful neo-bursitis. Although Baastrup’s disease was described as early as 1929, it remains of debated significance. This is in part due to the lack of adequate research correlating anatomic, imaging, and clinical factors. METHODS 862 patients with prior non-enhanced MRI of the lumbar spine, and CT or lumbar spine radiograph (DX) were reviewed for presence of intimately approximated spinous processes (“kissing spine”). MRI-STIR sequence images of this patient subset were reviewed for presence of lumbar interspinous bursitis (LIB). Same-level and aggregate degenerative disc disease (DDD), listhesis, fracture, and facet hypertrophy (FH) were analyzed. RESULTS Of 862 patients, 100 (11.6 %) had “kissing spine” changes. 17 of these 100 had evidence of LIB affecting a total of 22 levels. Bursitis was most common at L4/5 and L5/S1 (n=9), accounting for the majority of cases (81.8 %). Vertebral body fracture was positively correlated with bursitis, with odds ratio of 1.84. Mean degenerative change was less in the LIB subset (p=0.029). CONCLUSION Baastrup’s disease refers to a disease spectrum in which lumbar spinous processes hypertrophy and undergo repetitive mechanical friction. This leads to interspinous ligamentous degeneration, adventitial recruitment, and ultimately produces neo-bursitis in a small patient subset. Since degenerative changes and hypertrophied spinous processes (“kissing spine”) are nearly ubiquitous in an elderly population, many hypothesize that Baastrup’s is a merely harbinger of global aging-related degenerative changes. We propose that the interspinous bursitis component of the Baastrup’s spectrum is present in a small proportion of patients and likely corresponds with more advanced disease. Our data suggest that lumbar interspinous bursitis may be associated with a lesser degree of gloal degenerative change. There is suggestion of a positive correlation between interspinous bursitis and compression fracture at any level, possibly related to altered lumbar spine mechanics and load-bearing. Keywords Baastrup's, bursitis, degenerative MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 3 09:00–10:00 PARALLEL SCIENTIFIC SESSION - STROKE ANEURYSM/AVM CO.02.01 RECONSTRUCTIVE THERAPY WITH STENT FOR PARTIALLY T H R O M B O S E D A N E U RY S M S I N T H E P O S T E R I O R CIRCULATION T. Nakazawa, K. Higuchi, T. Yokoi, M. Tanimoto, H. Kimura, K. Takagi, N. Nitta, J. Jito, T. Fukami, K. Nozaki Shiga University of Medical Science, Otsu, Japan Patients with partially thrombosed large cerebral aneurysm in the posterior circulation have poor prognosis, however, early intervention should be considered and the optimum treatment for thrombosed aneurysms remains unknown. It is difficult to manage these aneurysms by conventional clipping. Sophisticated bypass surgery may have a good outcome, but some patients treated with flow alteration resulted in critical status, owing to ischemia of perforators including in the blind sac of arterial segment. Although endovascular treatment consists of parent occlusion with coils is effective in well-tolerated patients, some reported cases of partially thrombosed giant vertebral artery aneurysm that showed continued growth even in the absence of angiographic filling after endovascular trapping. So-called abluminal aneurysmal vasculopathies make neoangiogenesis of vaso vasorm to an aneurismal wall, and the increased amount of vaso

Neuroradiology (2013) 55 (Suppl 1):S15–S159 vasorum at the aneurysmal wall contributes growing in size. Direct coiling to aneurysmal sac causes migration of coils often. Recently, endovascular therapy with Enterprise VRD for cerebral large aneurysm started in Japan and good results reported from many . We report the clinical presentation and outcome of four patients with thrombosed cerebral aneurysms treated with VRD. Thirty-two patients with unruptured cerebral aneurysm were performed the endovascular treatment using VRD with or without coils. In this group, four patients had the partially thrombosed aneurysms. VRD were delivered in all patients, in 2 patients without coils, and in two patient who harbored a partial thrombosed aneurysm with coils. A symptomatic patient treated with VRD only died 2 months after procedure, due to rupture of the aneurysm. It seems that proximal side of VRD migrated to intra-aneurysmal space occurred a few days after deployment successfully and this condition was harmful to aneurysmal wall. Three other patients with non-giant aneurysm are stable in size of aneurysm and no episode has occurred. In conclusion, reconstructive endovascular therapy is one of the alternative therapy for partially thrombosed cerebral aneurysms, when the aneurysm was not so large. Single stent placement may not be enough for control of aneurysm growing or stent migration. Overlapping stents or stent with coils may have the effectiveness. Keywords Thrombosed aneurysm, endvascular treatment, stent CO.02.02 IS PREOPERATIVE STATIN THERAPY EFFECTIVE ON REDUCING DWI POSITIVE MICROEMBOLISM DURING COILING OF UNRUPTURED CEREBRAL ANEURYSMS? T. Matsushige1, Y. Kiura1, S. Sakamoto1, T. Okazaki1, K. Shinagawa1, N. Ichinose1, M. Takasu2, Y. Akiyama2, K. Kurisu1 1 Department of Neurosurgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan, 2Department of Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan

PURPOSE The aims of this retrospective cohort study are to assess whether the use of statin would reduce periprocedural microembolism after coil embolization of unruptured cerebral aneurysm with focus on plasma lipid levels. METHODS The records of 45 consecutive patients with cerebral aneurysms treated by coiling were analyzed. All patients received antiplatelet agents premedication and 28 of 45 (62.2 %) were on statins at the time of coiling. We evaluated baseline fasting plasma lipid levels as low and high-lipoprotein cholesterol (LDL-C and HDL-C), the ratio of LDL-C to HDL-C (LDL-C/HDL-C), non-HDL-C, and triglyceride one day before the intervention. Thromboembolic events were assessed with new focal spots of high signal intensity on diffusion-weighted MR images (DWI) obtained within 24–48 hours after the procedure. We also analyzed the area of a total of 102 spots of high signal intensity. To compare differences between two groups, we used Fisher exact test for categorical factors and the Mann–Whitney U-test for quantitative variables. Statistical significance was assigned when p<0.05. RESULTS Twenty-nine patients (64.4 %) showed high signal spots on DWI, however all were asymptomatic. DWI positivity was significantly smaller in statin users (50 %) than in non-statin users (88.2 %, p=0.0116); 14(50 %) of 28 patients with dyslipidemia under statins therapy, 7(87.5 %) of 8 with dyslipidemia without statin and 8(88.9 %) of 9 with normolipidemia without statin. Patients with DWI positive had significantly high plasma LDL-C (p = 0.0124) and non-HDL-C (p=0.0370). The cutoff value of LDL-C for predicting DWI positivity was 120 mg/dl (sensitivity 53.6 %, specificity 81.3 %). Non-statin users had significantly larger number of high signal spots over 6 mm in diameter than statin users.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSION Preoperative statin use may enhance to reduce the risk of microembolism detected on DWI after coiling of unruptured cerebral aneurysms. Keywords Thromboembolism, coil embolization, statin CO.02.03 RELIABILITY OF USING QUANTITATIVE DIGITAL SUBTRACTION ANGIOGRAPHY TO MONITOR CEREBRAL HEMODYNAMIC IN PATIENTS WITH SUBARACHNOID HEMORRHAGE-A PILOT STUDY C. Lin1, W. Guo1, S. Hung1, C. Lin2, B. Hsu2, W. Chu1 1 Taipei Veterans General Hospital, Radiology Department, Taipei, Taiwan, 2Taipei Veterans General Hospital, Neurosurgery Department, Taipei, Taiwan

BACKGROUND In-room assessment of cerebral hemodynamic helps to confirm the severity of the subarachnoid hemorrhage (SAH) and predict the development of vasospasm and patient outcome. The aim of our study is to confirm the correlation of cerebral circulation time (CCT) derived from the quantitative digital subtraction angiography (DSA) and CT perfusion (CTP). MATERIAL AND METHODS Twenty SAH patients with available DSA and CTP were retrospectively included in our study. The mean interval between two exams was 4.5 hours. The CCT from DSA (XA-CCT) was defined as the difference of Tmax (Time of maximum intensity) between the selected arterial ROIs and superior sagittal sinus ( SSS). Four selected arterial ROIs were selected to generate four corresponding XA-CCTs: second portion of right and left anterior cerebral arteries (XA-CCTRA2 and XACCTLA2), the insular banch of right and left middle cerebral arteries (XA-CCTRM2), and (XA-CCTLM2). The CCT from CTP (CT-CCT) were defined as the difference of TTP from the corresponding arterial ROIs and SSS. Different CCTs were compared between vasospasm and control groups. RESULT The intraclass classification of CCTs merited from DSA between two observers ranged 0.96-0.97, and those from CTP between two observers ranged 0.96-0.98. The correlation of XA-CCTRA2, XA-CCTRM2, XA-CCTLA2, and XA-CCTLM2 with the corresponding CT-CCTs were 0.67, 0.68,0.75,0.77, respectively. All-CCTs were significant prolonged in vasospasm group (6.9-7.6 seconds) except XACCTRA2, and XA-CCT RM2. CONCLUSION The XA-CCTs measured by quantitative color-coded DSA can reliably provide cerebral hemodynamics in SAH patients and successfully predicted those who were predisposed to develop vasospasm. Keywords Quantitative DSA, subarachnoid hemorrhage, vasospasm CO.02.04 TREATMENT OF DISSECTING ANEURYSMS OF THE POSTERIOR INFERIOR CEREBELLAR ARTERY: A NATO MICAL CONSIDERATIONS AND CLINICAL CONSEQUENCES R. Van Den Berg, T.C. Doorschodt, M.E.S. Sprengers, W.P. Vandertop Academic Medical Center, Amsterdam, The Netherlands BACKGROUND AND PURPOSE Posterior inferior cerebellar artery (PICA) dissecting aneurysms require rapid and aggressive treatment by sacrificing the parent vessel of the

S45 aneurysm-bearing dissected vessel. In this study, we assessed the clinical consequences of PICA vessel occlusion in view of the local vascular anatomy. MATERIALS AND METHODS We performed a retrospective search of our neurovascular database in the period 2007–2012. Patient characteristics, clinical presentation and outcome, and the detailed vascular anatomy including collateral circulation were recorded. RESULTS We identified 12 patients (6 male; mean age 51 years; range 21–63). Ten patients presented with WFNS grade I and II, the other patients with grade III and V. Outcome was favorable in 11 patients; one patient died due to the mass effect of the cerebellar hematoma. In ten patients, treatment consisted of parent vessel occlusion, the other two with selective aneurysm coiling. An extradural PICA origin and downstream dissecting aneurysms were present in five patients. Collateral circulation was visible prior to occlusion in three patients, after occlusion in another five patients. Only one of these eight patients showed clinical and radiological signs of cerebellar ischemia. The two patients without collaterals both developed ischemia. No patient developed a Wallenberg syndrome. CONCLUSION In this study, parent vessel occlusion for treatment of PICA dissecting aneurysms was well tolerated with a favorable outcome in 11 out of 12 patients. Regional collateral circulation from the ipsilateral anterior inferior cerebellar artery (AICA) and superior cerebellar artery and contralateral PICA was sufficient to prevent severe cerebellar ischemia. Keywords Aneurysm, arterial dissection, subarachnoid hemorrhage CO.02.05 ENDOVASCULAR REPAIR OF POSTERIOR COMMUNICATING ARTERY ANEURYSMS, ASSOCIATED WITH OCULOMOTOR NERVE PALSY: A REVIEW OF NERVE RECOVERY M. Sheehan, S. Looby Beaumont Hospital , Department of Radiology, Dublin, Ireland PURPOSE Oculomotor nerve palsy (ONP) is often the presenting symptom in patients with posterior communicating artery (PCOMM) aneurysms. Recovery of oculomotor nerve function is highly variable in this group. In this study we report the ophthalmologic outcome of 20 patients treated by endovascular coiling for PCOMM aneurysm induced ONP, in an Irish population. MATERIALS In our institute there were 230 endovascular coilings of PCOMM aneurysm between the years 2006 and 2011. Twenty of the 230 cases presented with oculomotor nerve dysfunction. We observed the degree of nerve recovery i.e. complete, partial or none whilst also documenting other predictive factors such as: degree of pre-intervention nerve deficit, presence of subarachnoid hemorrhage, size and location of the PCOMM aneurysm and length of follow up. RESULTS Of the 20 patients, 9 (45 %) presented with complete ONP and 11 (55 %) with partial ONP. After an average follow up period time of 16 months there was 9 (45 %) complete recoveries and 11 (55 %) partial recoveries. Of the 9 patients who presented with complete ONP 5 patients (56 %) made a complete recovery and 4 (44 %) made a partial recovery. Of the 11 who initially presented with partial ONP 4 patients (36 %) made a complete recovery and 7 (64 %) made a partial recovery. Seven (35 %) patients also had a SAH, 3 (43 %) of whom made a complete recovery with 4 (57 %) making a partial recovery.

S46 CONCLUSIONS ONP can occur with PCOMM aneurysm with or without SAH. Endovascular coiling is now the preferred treatment for this. Our study demonstrates that 45 % of this patient group can make a complete recovery in oculomotor nerve function. Keywords Endovascular intervention, posterior communicating artery, oclomotor nerve palsy CO.02.06 INTRA-ANEURYSMAL FLOW DISRUPTION: A NEW APPROACH FOR THE ENDOVASCULAR TREATMENT OF INTRACRANIAL ANEURYSMS. FRENCH CLINICAL EXPERIENCE L. Pierot1, A.C. Januel2, H. Raoult3, L. Spelle4, C. Papagiannaki5, H. Desal6, P. Courtheoux7, K. Kadziolka1, J.Y. Gauvrit3, J. Moret4, D. Herbreteau5, C. Cognard2 1 Chu Reims, Reims, France, 2Chu Toulouse, Toulouse, France, 3Chu Rennes, Rennes, France, 4Hopital Beaujon, Clichy/Paris, France, 5Chu Tours, Rennes, France, 6Chu Nantes, Nantes, France, 7Chu Caen, Caen, France

PURPOSE Standard coiling is now the first line approach for the treatment of intracranial aneurysms. However, this technique has some limitations, including treatment of wide-neck and large and giant aneurysms and recanalizations. Therefore, new techniques and devices are needed. The objective of intra-saccular flow disruption is the modification of aneurysmal flow by placing a device in the aneurysm sac. Preliminary clinical experience in French centers is presented. MATERIALS AND METHODS Computational fluid dynamics and pre-clinical testing (canine crossover carotid bifurcation model) were used to develop an intra-saccular flow disrupter design, designated as WEB (Sequent, Aliso Viejo, CA). The WEB is a self-expanding, oblate, braided nitinol mesh, composed of an inner and outer braid held together by proximal, middle, and distal radio-opaque markers and creating two compartments: one distal and one proximal. Clinically, 50 patients (37 F/13 M, age: 37–75 years) harbouring 51 ruptured, unruptured or recanalized aneurysms were treated between June 2011 and March 2013 in 7 French centers, using an intra-aneurysmal flow-disrupter (WEB). Aneurysm location was middle cerebral artery (31 aneurysms), basilar artery (10), internal carotid artery (6), and anterior communicating artery (4). Aneurysm size was <5 mm in 1 aneurysm, 5-10 mm in 44 aneurysms, and >10 mm in 6 aneurysms. Neck size was<4 mm in 6 aneurysms and>=4 mm in 45 cases. RESULTS Clinically, the device was successfully deployed in all but 2 cases. One intraoperative rupture was observed with no clinical worsening. Four thromboembolic events were observed with favorable outcome in 3 cases (mRS<=2). No delayed rupture or remote hematoma was observed. Additional coiling was performed in 5 cases, remodeling in 1 case, and stenting in 1 case. Mid-term follow-up results are presented. CONCLUSION Intra-saccular flow disruption using WEB is a completely new endovascular approach to treat some types of aneurysm, particularly wide-neck bifurcation aneurysms. This preliminary clinical experience shows the safety and efficacy of the device when used in appropriately selected cases. Keywords Aneurysm, endovascular treatment, flow disruption

Neuroradiology (2013) 55 (Suppl 1):S15–S159 MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 3 11:30–13:00 PARALLEL SCIENTIFIC SESSION - BRAIN TUMORS 1 CO.03.01 COMPARISON OF ARTERIAL SPIN LABELLING AND DYNAMIC SUSCEPTIBILITY-WEIGHTED CONTRAST-ENHANCED MR PERFUSION IMAGING IN BRAIN TUMOURS Y. Ozsunar Dayanir1, S. Ata1, Y. Durum1, M. Turgut2 1 Adnan Menderes University Faculty of Medicine, Department of Radiology, Aydin, Turkey, 2Adnan Menderes University Faculty of Medicine, Department of Neurosurgery, Aydin, Turkey

PURPOSE The purpose of this study was to preliminarily compare arterial spin-labelled (ASL) imaging with dynamic susceptibility contrastenhanced cerebral blood volume (DSCE-CBV) Magnetic Resonance Imaging for evaluation of tumour perfusion in patients with brain tumours. METHODS Patients with brain tumours were examined in 1,5 T MRI. Single phase and multiphase ASL, DSCE-CBV examinations were assessed by both qualitative and quantitative analysis for the detection of malignancy. Imaging results were correlated with a histopathology or follow-up. RESULTS Thirty-one cases were studied with both 31 ASL and DSCE-CBV examinations. On the basis of visual inspection, the sensitivities of ASL and DSCE-CBV examinations for detecting malignant tumor were 78 % and 84 % respectively. The highest sensitivity values for quantitative analyses were obtained using a normalized cut-off ratio of 1,05 for ASL , and 1,45 for DSCE-CBV imaging resulting in sensitivity of 94 % for ASL imaging and 95 % for DSCE-CBV imaging. Area under curve were calculated with ROC curve resulted 0,71 for ASL imaging and 0,87 for DSCE-CBV imaging. CONCLUSIONS Both ASL and DSCE-CBV are valuable method for assessment of microvascular perfusion and provides comparable high sensitivity and specificity values. However, quantitative DSCE-CBV analyses provided better diagnostic performance comparing ASL technique. Keywords Brain tumors, perfusion Imaging, functional imaging CO.03.02 PROTON MR SPECTROSCOPY COULD BE USEFUL IN THE DIAGNOSIS OF PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA (PCNSL) P. Mora1, M. Cos2, A. Camins2, A. Muntané1, C. Aguilera2, C. Majós2 1

Neuroradiology and Neurointerventional Department, Hospital Universitari De Bellvitge, Barcelona, Spain, 2Institut Diagnòstic per la Imatge (Idi), Hospital Universitari De Bellvitge, Barcelona, Spain PURPOSE To assess whether MR Spectroscopy (MRS) could be useful to reinforce the radiological suspicion of PCNSL by helping to differentiate these lesions from other brain tumors. METHODS We retrospectively reviewed 366 patients (201 men and 165 women; mean age, 57 years) with a brain tumor in which spectroscopy at short TE was performed between 1998 and 2012. All tumors except some

Neuroradiology (2013) 55 (Suppl 1):S15–S159 metastases had a definitive histological diagnosis and correspond to lymphoma (LYMP, n=17), meningioma (MEN, n=61), low grade astrocytoma (LGA, n=31), anaplastic astrocytoma (AA, n=49), glioblastoma (GB, n=124) and metastasis (MET, n=84). The MRS was evaluated as a series of numbers that delineate the graphics shown as spectra. Each point in the spectrum was considered to be a variable for the statistical analysis. Each type of tumour was compared to PCNSL by using the Mann–Whitney U nonparametric test. The obtained P values were corrected by using the Hochberg method. Only data points with significance level better than P<0.05 were retained for further analysis. Receiver operating characteristic (ROC) curves were constructed for each one of the points obtained. Then the cut-off points with an optimal sensitivity/specificity relationship were selected to be used as thresholds for the classification. These spectroscopic variables with the selected cut-off points were used as classifiers for binary comparison of PCNSL vs non-PCNSL. RESULTS Significant differences were found between PCNSL and the rest of groups. The most relevant differences between MEN and PCNSL were found in the GLX and ALA area. Significant differences between PCNSL and LGA, and between PCNSL and AAwere found in the resonances CR, CHO and MI. Glioblastoma showed a pattern of differences similar to that of MET, being high lipids the most relevant signature. The elective resonances defined by ROC curves for each bilateral comparison were considered to be 1.22 ppm lipids for MEN, MI for LGA and AA, and 1.28 ppm lipids for GB and MET. These vales showed an accuracy greater than 70 % (70-94 %). CONCLUSIONS To consider MRS as a series of numbers and to perform bilateral comparisons of the spectra may be useful in the differentiation of PCNSL and other intracranial tumors. Keywords Spectroscopy, lymphoma, brain tumors CO.03.03 PH CHANGES IN RECURRENT GLIOBLASTOMAS DURING BEVACIZUMAB MEASRED WITH 31P MR SPECTROSCOPY U. Pilatus1, V. Voelker1, M. Hardt1, O. Baehr2, E. Hattingen1 Neuroradiology, Goethe University, Frankfurt, Germany, 2Dr. Senckenberg Institute of Neurooncology, Goethe University, Frankfurt, Germany 1

PURPOSE Hypoxia and other biochemical changes in the tumoral environment may enhance glycolysis, augmenting lactic acid production. Thus, increased extracellular acidosis causes an increase of intracellular pH by upregulation of H+extrusion and buffering pathways. 31P MR spectroscopic imaging (MRSI) offers a tool to monitor intra- and extracellular pH in the brain. Results to lipid and energy metabolism were recently published (1). In this study we evaluated whether antiangiogenic treatment is affecting the intracellular pH. METHODS 1H and 31P MRSI was prospectively performed in 32 patients with rGBMs before and under BVZ therapy at 8 weeks intervals until tumor progression. The pH values of the tumor and normal appearing brain tissue (control) were determined from the chemical shift difference phosphocreatine signal and inorganic phosphate with the program jMRUI. Wilcoxon signed-ranks test was used to compare tumor tissue to control as well as tumor tissue before and during therapy. RESULTS Before treatment the tumor, pH was increased by 0.07 (+/− 0.02) units. 8 weeks after treatment the pH was dropped by 0.05 units (almost

S47 normal). While the treatment continues the pH increases gradually reaching typical values for tumor tissue when the tumor progressed again. CONCLUSION The measurement of pH by 31P MRSI seems to be a rather sensitive method for monitoring initial effects of treatment with bevacizumab as well as tumor progression under this antiangiogenic treatment. However, partial volume effects due to the poor point spread function in 31P MRS have to be considered in interpretation of the results. (1) Hattingen E, Bähr O, Rieger J, Blasel S, Steinbach J, Pilatus U. PLoS One. 2013;8:e56439 Keywords Glioblastoma, phosphorus spectroscopy, PH CO.03.04 FACTORS CONTRIBUTING TO ITSS-MORPHOLOGY IN PATIENTS WITH GLIOBLASTOMA MULTIFORME D. Fahrendorf 1 , V. Hesselmann 1 , W. Schwindt 1 , J. Wölfer 2 , H. Kooijman3, H. Kugel , W. Heindel1, A. Bink1 1 University Hospital Münster, Department of Clinical Radiology, Münster, Germany, 2University Hospital Münster, Department of Neurosurgery, Münster, Germany, 3Philips Healthcare, Clinical Application, Hamburg, Germany

PURPOSE The complexity of intratumoural susceptibility signal (ITSS) morphology in the assessment of patients with glioblastoma multiforme (GBM) still remains a challenge. The aim of this study was to outline variations in ITSS morphology and their relationship to the location of the lesion within the brain parenchyma. METHODS A total of 32 patients with histologically confirmed glioblastoma multiforme participated in this study. SWI images were analysed with particular regard to ITSS-morphology ranging from score 0 (=no ITSS) to score 4 (=dense and conglomerated ITSS). Considering the location of the lesion within brain parenchyma, lesions with and without involvement of the subventricular zone (SVZ+ /SVZ-) were discerned. Additionally, the contrast-enhancing tumour volumes were analysed. Statistical analysis included Spearman’s rank correlation coefficient, Mann–Whitney-U-test, and KruskalWallis-test. RESULTS The distribution of ITSS-scores showed significant differences between the SVZ+and SVZ- groups (p<0.002). While glioblastomas without involvement of the SVZ had ITSS-scores ranging from 0 to 2, SVZ+ GBM were associated with higher ITSS-scores (predominantly 3 and 4). Additionally, a significant positive correlation of higher ITSS-scores to larger tumour volumes (p<0.01, in a two-tailed analysis: Spearman’s rho r=0.692)) was found. CONCLUSION Our findings indicate that ITSS morphology is not a random phenomenon. Location of GBM and involvement of the subventricular zone, potentially associated with neural stem cell regions, as well as tumour volume, appear to be contributing factors to ITSS morphology. Abbreviations: CE-T1w = contrast-enhanced T1 weighted imaging; GBM=glioblastoma multiforme; ITSS=intratumoural susceptibility signals; MRI=magnetic resonance imaging; SVZ=subventricular zone; SWI=susceptibility weighted imaging Keywords Glioblastoma multiforme, SWI, subventricular zone

S48 CO.03.05 BENEFITS OF CONTRAST-ENHANCED SWI IN PATIENTS WITH GLIOBLASTOMA MULTIFORME D. Fahrendorf1, W. Schwindt1, J. Wölfer2, A. Jeibmann3, H. Kooijman4, H. Kugel1, O. Grauer5, W. Heindel1, V. Hesselmann1, A. Bink1 1 University Hospital Münster, Department of Clinical Radiology, Münster, Germany, 2University Hospital Münster, Department of Neurosurgery, Münster, Germany, 3University Hospital Münster, Institute of Neuropathology, Münster, Germany, 4Philips Healthcare, Clinical Application, Hamburg, Germany, 5University Hospital Münster, Department of Neurology, Inflammatory Disorders of the Nervous System and Neurooncology, Münster, Germany

PURPOSE SWI can be used to differentiate LGG from HGG. The objective of this study was to analyse SWI and CE-SWI characteristics, i.e. the relationship between contrast-induced phase shifts (CIPS) and intratumoural susceptibility signals (ITSS) in patients with glioblastoma multiforme (GBM). METHODS MRI studies of 29 patients were performed to evaluate distinct susceptibility signals with a focus on the comparison of SWI and CE-SWI characteristics. The relationship between these susceptibility signals and CE-T1w tumour volume was analysed by using Spearman’s rank correlation coefficient and Kruskal-Wallis-test. Tumour biopsies of distinct susceptibility signals were performed in one patient. RESULTS Comparison of SWI and CE-SWI demonstrated different susceptibility signals. Susceptibility signals visible on SWI images are consistent with ITSS, those only seen on CE-SWI were identified as CIPS. Correlation with CE-T1w tumour volume revealed that CIPS were especially present in small or medium-sized GBM (Spearman’s rho r=0.843, p<0.001). Histology identified the area with CIPS as the tumour invasion zone, while the area with ITSS represented micro-hemorrhage, highly pathological vessels, and necrosis. CONCLUSION CE-SWI adds information to our understanding of pathological changes during the growth of GBM and has the potential to improve preoperative planning, i.e. identification of the tumour invasion zone. Abbreviations: CE-SWI=contrast-enhanced susceptibility weighted imaging; HGG=high grade glioma; ITSS=intratumoural susceptibility signals; LGG=low grade glioma; MRI=magnetic resonance imaging; CIPS=contrast-induced phase shifts; SWI=susceptibility weighted imaging; CE-T1 WI = contrast-enhanced T1 weighted imaging Keywords Glioblastoma multiforme, CE-SWI, tumour invasion zone CO.03.06 DIFFERENTIATION OF VASOGENIC EDEMA FROM TUMORINFILTRATED EDEMA USING DTI, RCBV AND MR SPECTROSCOPY. A PROSPECTIVE STUDY OF 25 PATIENTS F. De Belder1, M. De Belder2, C. Venstermans1, J. Van Goethem1, L. Van Den Hauwe1, T. Van Der Zijden1, M. Voormolen1, P.M. Parizel1 1

Antwerp University Hospital, Radiology, Antwerp, Edegem, Belgium, Ghent University, Department of Experimental Psychology, Ghent, Belgium

2

PURPOSE To validate the effectiveness of magnetic resonance spectroscopy (MRS), relative cerebral blood volume (rCBV) mapping, diffusion

Neuroradiology (2013) 55 (Suppl 1):S15–S159 tensor imaging (DTI), fractional anisotropy (FA) and apparent diffusion coefficient (ADC), in the differentiation of vasogenic edema from tumor-infiltrated edema. METHODS We performed a prospective study of 25 patients with brain tumors (10 high grade gliomas, 8 metastases and 7 meningiomas surrounded by vasogenic edema). All diagnoses were histologically confirmed. Proton MRS (with measurement of the choline/creatine ratio (Cho/Cr)), dynamic susceptibility contrast (DSC) perfusion (used to calculate rCBV curves and values) and DTI (from which FA and ADC were computed) were performed on a 3 T and a 1.5 T MR-scanner, using dedicated phased array head coils. The Cho/Cr ratio and rCBV were also measured in the peritumoral edema. FA and ADC measurements in the peritumoral edema and the contralateral normal white matter, and the ratio of peritumoral edema/normal contralateral white matter were calculated. RESULTS In tumor-infiltrated edema, Cho/Cr ratios were significantly higher (1.4+/−0.61) than in pure vasogenic edema (0.9+/−0.13). rCBV curves demonstrated a higher rCBV values in tumor-infiltrated edema (2.1+/−1.51) than in vasogenic edema (0.9+/−0.22). FA and ADC values were higher in pure vasogenic edema (surrounding meningiomas and metastases)(FA 0.17 +/−0.13, ADC 1.67 +/−0/25) than in tumor-infiltrated edema (surrounding infiltrating glial tumors)(FA 0.12 +/−0.05, ADC 1.60+/−0.26). There was, however, a significant overlap between the two groups. CONCLUSIONS Multiparametric imaging (MRS, DSC-perfusion and DTI), added to conventional MR-imaging, can be helpful to differentiate vasogenic edema from tumor-infiltrated edema. Especially MRS and rCBV seem to be particularly useful; FA and ADC are indicative, but not reliable due to significant data overlap between the two types of edema. Accurate differentiation has important clinical consequences; therefore we advocate that multiparametric imaging should be included in the diagnostic workup of brain tumors in order to outline tumor boundaries and assess resectability. Keywords Peritumoral edema, MR Spectroscopy, DTI CO.03.07 CORRELATION OF EXTRAVASCULAR EXTRACELLULAR SPACE OF TREATED GLIOBLASTOMAS BETWEEN DYNAMIC CONTRAST ENHANCEMENT MAGNETIC RESONANCE PERFUSION AND DIFFUSION TENSOR IMAGING V. Cuvinciuc1, A. Varoquaux2, M. Viallon2, O. Gurer2, I. Barnaure Nachbar2, M.I. Vargas1, S. Haller1, K.O. Lovblad1 1 University Hospitals of Geneva, Imaging Department, Neuroradiology Unit, Geneva, Switzerland, 2University Hospitals of Geneva, Imaging Department, Radiology Unit, Geneva, Switzerland

PURPOSE Verify the potential correlation between mean diffusivity (MD) on diffusion tensor imaging (DTI) and leakage space (ve) on dynamic contrast enhancement (DCE) perfusion imaging as parameters of the extravascular extracellular space (EES) in treated glioblastomas. METHODS 44 patients with glioblastomas after radiochemotherapy were considered for this retrospective, ethics committee-approved study. All patients had at least a MR exam on a 3 T machine, including DTI (30 directions, b=0 and 1000 s/m2) and DCE (T1 mapping with dual flip angle; 5 min30 sec acquisition time of the dynamical T1 VIBE sequences). Inclusion criterion was the presence of enhancing lesions on follow-up MR exams; exclusion criteria were significant artifacts (e.g. movement artifacts, susceptibility artifacts on DTI images), small

Neuroradiology (2013) 55 (Suppl 1):S15–S159 enhancing lesions (area less than 0.5 cm2). 16 patients were finally included. One MR exam was considered for each patient, with the largest enhancing lesion and less artifacts. MD and ve maps were computed with commercially available software; DCE images were reconstructed using a two-compartments model (Tofts, Tofts extended) and tissue homogeneity model (Lawrence and Lee, Lawrence and Lee delay). 2D regions of interest (ROIs) were drawn loosely around the enhancing lesions on T1-weighted images after gadolinium administration. A semi-automatic algorithm was applied in order to segment the enhancing lesion and to exclude voxels with susceptibility artifacts. Resulting ROIs were copied on coregistered MD and ve maps. Mean values and standard deviation were compared using nonparametric Spearman coefficient. RESULTS Spearman r correlation coefficient between MD and ve maps (based on Tofts model, Tofts extended model, Lawrence and Lee, Lawrence and Lee delay) was calculated at 0.3777, 0.3839, 0.3379 and 0.3761, respectively (P<0.005). CONCLUSION Although MD and ve are both parameters used to describe EES, they are only fairly correlated in treated glioblastomas, reflecting probably limitations of the current models. Further work is necessary to explore other models (such as subcompartimentalization of the EES, water exchange between the cellular and extracellular spaces etc.). Keywords Glioblastoma, dynamic contrast enhancement, diffusion tensor imaging CO.03.08 MR PERFUSION IN AND AROUND THE CONTRASTENHANCEMENT OF PRIMARY CNS LYMPHOMAS S. Blasel1, A. Jurcoane1, O. Baehr2, L. Weise3, P.N. Harter4, E. Hattingen1 1

Institute of Neuroradiology, Goethe University Hospital Frankfurt, Frankfurt, Germany, 2Dr. Senckenberg Institute of Neurooncology, Goethe-University Hospital Frankfurt, Frankfurt, Germany, 3Department of Neurosurgery, Goethe-University Hospital Frankfurt, Frankfurt, Germany, 4Edinger Institute, Institute of Neurology, Goethe-University Frankfurt, Frankfurt, Germany PURPOSE In glioblastomas MR-perfusion visualizes diffuse cerebral tumor infiltration into the non-enhancing brain tissue adjacent to the contrast enhancing area (penumbra) through elevated regional cerebral blood volume (rCBV) values. Primary central nervous system lymphomas (PCNSL) may also diffusely infiltrate the brain tissue adjacent to the obvious tumor mass. We aimed to evaluate if penumbral rCBV is also increased in PCNSL and compared the MR perfusion features of PCNSL and glioblastomas. METHODS Dynamic susceptibility contrast (DSC) MR-perfusion was performed at 3 Tesla in 38 presurgical patients with solid contrast-enhancing tumors and the histopathological diagnosis of either PCNSL (n=19) or glioblastoma (n=19). We normalized the rCBV within the enhancing tumor and the penumbra to the values in the contralateral normal brain and compared them between PCNSL and glioblastomas. Further, we visually evaluated if the time-signal intensity curves (TSIC) showed a shoulder-like increase over baseline level after the first pass signal drop and histologically compared the patients with and without shoulder-like TSIC pattern. RESULTS Relative to the normal tissue, rCBV within and adjacent to the enhancing area was increased (p<0.05) in both groups. In the penumbra the rCBV increase was moderate in both groups, with

S49 1.4 ± 0.46 in PCNSL and 1.82 ± 0.82 in glioblastomas (p = 0.07 between groups). In the enhancing tumor the increase was moderate in PCNSL (1.4±0.62) and marked in glioblastomas (4.13±2.44) (p<0.001 between groups). A shoulder-like TSIC increase was exclusively found in PCNSL (11/19) and was significantly associated with a less prominent reticulin fibre network compared to the PCNSL without a shoulderlike TSIC increase. CONCLUSIONS Normalized rCBV values and pattern of TSIC represent important perfusion features of malignant primary brain tumors that are invisible on conventional MRI. Increased rCBV in the penumbral area beyond the enhancing tumor may detect tumor infiltration in both, PCNSL and glioblastomasand may differentiate them from noninfiltrative lesions like metastases. A shoulder-like TSIC not only excludes glioblastomas, but also characterizes PCNSL with less dense reticulin fibre networks. Keywords Primary CNS lymphoma, tumor infiltration, rCBV CO.03.09 A S S ES S M E N T O F P R O G R E S S I O N - F R E E - S U RV I VA L AND THERAPY RESPONSE IN GLIOBLASTOMAS BY INTRATREATMENT DYNAMIC CONTRAST-ENHANCED MRI S. Bisdas1, U. Smrdel2, F. Bajrovic3, K. Surlan-Popovic4 1 University of Tübingen, Department of Neuroradiology, Tübingen, Germany, 2Oncology Institute, Department of Radiation Therapy, Ljubljana, Slovenia, 3University of Ljubljana, Department of Neurology, Ljubljana, Slovenia, 4University of Ljubljana, Department of Neuroradiology, Ljubljana, Slovenia

PURPOSE The efficacy of concomitant chemoradiation in patients with glioblastomas (GBMs) cannot be reliably assessed until months after therapy completion. Our aim was to evaluate dynamic contrastenhanced (DCE) MRI as an early predictive assay for treatment response and survival that would potentially lead to therapy tailoring. METHODS Twenty-two patients with primary GBMs underwent DCE-MRI before, during and after completion of adjuvant chemoradiation. Ktrans (transfer constant between the intravascular and extravascular, extracellular space), ve (extracellular, extravascular volume) and iAUC (initial area under the signal intensity-time curve) and their changes into treatment were assessed as predictors of response (12 months of progression-freesurvival (PFS)). RESULTS Among 7 responders and 15 non-responders distinct patterns in the direction and magnitude of changes in tumour perfusion were revealed and reached statistical significance in the midtreatment ve as well as in the mid- and endtreatment Ktrans values. Cox regression analysis of baseline time-independent and timedependent perfusion variables demonstrated significant relationships between PFS and the changes in Ktrans values during the treatment. Trend to significant prognostic value demonstrated the baseline Ktrans, ve and iAUC as well as the change of iAUC upon therapy completion. CONCLUSIONS Early temporal perfusion changes during concomitant chemoradiation in glioblastomas can be detected by means of DCE-MRI and have significant prognostic value for the response to therapy and PFS. Keywords Glioblastoma, perfusion, treatment monitoring

S50 MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 4 11:30–13:00 PARALLEL SCIENTIFIC SESSION - PEDIATRICS CO.04.01 THE NEURONAL CORRELATES OF MIRROR ILLUSION IN CHILDREN WITH HEMIPARESIS: A PILOT STUDY USING FUNCTIONAL MRI C. Weisstanner1, S. Saxer4,5, A. Kaelin-Lang2, C.J. Newman3, M. Zbinden1, R. Wiest1, M. Steinlin4, S. Grunt4 1

University Institute of Diagnostic and Interventional Neuroradiology, University Hospital, Bern, Switzerland, 2Department of Neurology, University Hospital, Bern, Switzerland, 3Division of Neuropaediatrics and Rehabilitation, Nestlé Hospital CHUV, Lausanne, Switzerland, 4 Division of Neuropaediatrics, Development and Rehabilitation, Children University Hospital, Bern, Switzerland, 5Institute of Human Movement Sciences and Sport, ETH Zürich, Zürich, Switzerland AIM To investigate the neuronal mechanism underlying the effects of mirror therapy (MT) in children and adolescents with hemiparesis. INTRODUCTION MT provides the visual illusion of a normal moving paretic arm by using the mirror reflection of the non-paretic arm and is used in rehabilitation medicine to improve hand motor function. Despite promising clinical results, little is known about the neuronal correlates underlying the effect of MT in patients with hemiparesis. METHODS 12 children and adolescents with hemiparesis participated in this study. Functional MRI was performed to investigate neuronal activation patterns in two different viewing conditions; without and with mirror. Each condition consisted of a unimanual and a bimanual motor task. In the unimanual task, participants moved their non-paretic hand while looking at it directly (non-mirror condition) or while looking at its mirror reflection (mirror condition). During the bimanual motor task, participants moved both their hands simultaneously while looking at the paretic hand (nonmirror condition) or while looking at the mirror reflection of the non-paretic hand (mirror condition). RESULTS Data of 11 participants were suitable for analysis. Analysis showed a significant effect of mirror in the bimanual experiment (p< 0.001 (uncor.) at voxel level and P<0.05 (family-wise error corrected) at cluster level and minimum cluster size of 33 voxels). Activated regions were the precuneus (bilateral to the lesioned hand), superior frontal gyrus (ipsilateral), posterior cingulate cortex (contralateral), medial frontal lobe (ipsilateral) and middle occipital gyrus (contralateral). CONCLUSIONS In this study of neuronal correlates of mirror therapy in children and adolescents with hemiparesis, in bimanual experiment the mirror illusion increases activity in precuneus, posterior cingulate cortex, superior frontal gyrus, areas associated with self awareness/ reflection. We also find increased activity in the supplementory motor area (SMA). This finding provides neurophysiological evidence supporting the application of MT in children and adolescents. Keywords Functional MRI, children, hemiparesis CO.04.02 DIFFERENT PATTERNS OF CEREBELLAR ABNORMALITY AND HYPOMYELINATION BETWEEN POLR3A AND POLR3B MUTATIONS H. Tada1, J. Takanashi2, H. Mori3, H. Terada4, A. J. Barkovich5

Neuroradiology (2013) 55 (Suppl 1):S15–S159 1 Department of Pediatrics, Chibaken Saiseikai Nrashino Hospital, Narashino, Japan, 2Department of Pediatrics, Kameda Medical Center, Kamogawa, Japan, 3Department of Radiology, University of Tokyo, Tokyo, Japan, 4Department of Radiology, Toho University Sakura Medical Center, Sakura, Japan, 5Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA

BACKGROUND Mutations of POLR3A and POLR3B have been reported to cause several allelic hypomyelinating disorders, including hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome). Patients and methods: To clarify the difference in MRI between the two genotypes, we reviewed MRI in three patients (aged 16–31) with POLR3B mutations, and three (aged 15–44) with POLR3A mutations. The cerebellum was assessed for size and degree of enlargement of the fissures in the hemispheres and vermis. It was judged mildly abnormal when the cerebellar hemispheres and vermis were normal in size with mildly thin folia and mildly enlarged fissures, or they are small in size with almost normal folia. A moderately abnormal cerebellum was small with mildly thin folia and mildly enlarged fissures. The cerebellum was severely abnormal when it was small with extremely thin folia and very enlarged fissures. MR spectroscopy (PRESS TR/TE=5000/30, analyzed with LCModel) was performed in two of the three patients with POLR3B mutations. RESULTS MRI of the patients with POLR3B mutations revealed small cerebellum (hemispheres and vermis) with thin folia and enlarged fissures (judged as moderately abnormal in the hemispheres, and severely abnormal in the vermis). The pattern of decreased cortical thickness and diminished underlying white matter suggested cerebellar atrophy. MRI in the patients with POLR3A mutations revealed significantly less severe changes in the cerebellar hemispheres and vermis (judged as mildly to moderately abnormal). MR spectroscopy revealed increased concentrations of N-acetylaspartate and creatine with normal choline. CONCLUSIONS MRI findings are distinct between patients with POLR3A and 3B mutations, and can provide important clues for the diagnosis, as these patients sometimes have no clinical symptoms suggesting 4H syndrome. Keywords Hypomyelination, 4H syndrome, cerebellum CO.04.03 DIFFERENT IMAGING ASPECTS IN MALFORMATIONS OF CORTICAL DEVELOPMENT DEPENDING ON MYELINATION AND AGE – PICTORIAL ESSAY AND LITERATURE REVIEW M. Sarpi, L. Silva, L. Godoy, H. Lee, M. Docema, M. Martin, T. Lyra, D. Delgado Hospital Sírio Libanês, São Paulo, Brazil PURPOSE To review and demonstrate the disturbances of neuronal migration seen in radiological practice, depicting and discussing apparent modification of these findings through imaging follow up of the patients, demonstrating that they can be highlighted or obscured as development of the brain parenchyma evolves. METHODS Literature review and exemplification by clinical cases with magnetic resonance imaging (MRI) of malformations of cortical development seen in radiological practice, some of them exemplified by rare neurological syndromes, such as Aicardi syndrome. To review anatomic characteristics of the developing brain parenchyma, especially related to myelination, and to discuss possible factors related to variability of imaging findings over time along MRI follow up.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS We have observed that some cortical development disturbances are differently represented over time, accordingly to developmental aspects of the brain parenchyma, particularly related to myelination. As these patients often undergo imaging follow up, we will demonstrate that comparison with prior exams is very important for accurate identification of possible imaging findings. CONCLUSIONS Neuronal migration disturbances represent an important cause for epilepsy, and may also be related to encephalopathy, cognitive and motor development impairment. Associated malformations are frequent, and MR is the preferred method for imaging evaluation. It is important for the radiologist to recognize possible modifications that may occur during imaging follow up of these patients, acknowledging probable factors related to them. Keywords Cortical development, myelination, MRI CO.04.04 RADIOLOGICAL AND CLINICAL MANIFESTATIONS OF MEGALENCEPHALY-CAPILLARY MALFORMATION (M-CM) SYNDROME A. Sanchez-Montanez1, P.A. Parra Ramirez1, S. Boronat Guerrero2, I. Delgado Alvarez1, P. Cano Granda3, E. Vazquez Mendez1 1

Vall d'Hebron University Hospital - Diagnostic Imaging, Barcelona, Spain, Vall d’Hebron University Hospital - Pediatric Neurology, Barcelona, Spain, 3 Vall d’Hebron University Hospital - Neurosurgery, Barcelona, Spain 2

PURPOSE Megalencephaly-Capillary Malformation (M-CM) is a syndrome of unknown etiology whose main clinical symptoms are megalencephaly and capillary malformations, which frequently occur in the philtrum, upper lip and nose, also found in limbs and trunk. Other features include neonatal hypotonia, developmental delay, hydrocephalus, overgrowth, polydactyly, body asymmetry and connective tissue disorders. The most valuable neuroimaging findings include white matter lesions, cerebral asymmetry, ventriculomegaly, cerebellar tonsillar herniation, cortical dysplasia and polymicrogyria. The pathogenesis of hydrocephalus and tonsillar herniation is attributed to a combination of several factors, being the initial event a cerebellar rapid growth difficulting and distorting the dynamics of cerebrospinal fluid. To this date approximately 130 cases have been reported. The aim of this paper is to review the radiological findings of five patients with MCM recently studied in our institution, conducting a review of the literature. METHODS We reviewed the medical records of five patients with M-CM from 2005 to the current date in our institution. We describe their clinical and radiological findings, particularly MRI, comparing with those described in the literature. RESULTS The most common radiological findings in the five patients diagnosed with M-CM were tonsillar descent (5 / 5), ventriculomegaly (5 / 5), white matter lesions (4 / 5), dilated Virchow-Robin spaces (3 / 5), and abnormalities of venous sinuses and / or intracranial veins (3 / 5), findings consistent with those previously described. The most frequent clinical manifestations in our series were macrocephaly (5 / 5), developmental delay (4 / 5), overgrowth (5 / 5) and cutaneous manifestations such as midline facial nevus flammeus (5 / 5). CONCLUSIONS The recognition of typical imaging findings of M-CM is very important, especially in order to an early management of ventriculomegaly. Keywords Megalencephaly, capillary malformation, CSF dynamics

S51 CO.04.05 RESTRICTED DIFFUSION IN CHILDREN, SECONDARY TO CEREBRAL HYPOXIA: IDENTIFYING MRI SIGNS OF GOOD NEUROLOGICAL OUTCOME N. Pyatigorskaya, I. Haegy, R. Richard, D. Siahou, J. Bataille, R. Carlier Raymonnd Poincare, Garches, France PURPOSE The clinical outcome in children with cytotoxic edema which is secondary to cerebral hypoxia is difficult to predict. However, the right prognosis is essential, especially if the decision about reanimation has to be made. The purpose is to identify the MRI indications of positive clinical outcome of cytotoxic edema secondary to cerebral hypoxia in children in order to make the right decision regarding the intensive reanimation care. METHODS Retrospective analysis of five pediatric cases of cytotoxic edema in the context of hypoxia or respiratory failure by circulatory insufficiency was performed. Both clinical and radiological assessments were performed. Clinical examination was made on the day of the neurological deterioration and exit, and, in the case of resuscitation, a remote examination (1 year 2 months) was made. Radiological examination included MRI T1-weighted sequence in the sagittal plane, T2-weighted FLAIR, T2-weighted Gradiant Echo sequence in axial plane, DWI with a b0 and b1000 weighting and calculation of apparent diffusion coefficient (ADC) early D0 to D7 of the accident, then later to M1 D15 and the last one at M3. RESULTS Five patients aged 4 to 8 years showed significant impairment of consciousness (Glasgow coma scale less than 8), requiring mechanical ventilation. Three patients with diffuse cytotoxic edema of the white matter had favorable clinical outcome despite a significant decrease of ADC, with full neurologic recovery, the other two patients who had gray matter (cortical and basal ganglia) lesions associated with the white matter lesions and low ADC had negative evolution with vegetative coma (Glasgow coma scale less than eight). Despite a decrease in ADC, important cytotoxic edema was confined to the white matter, without any damage to the cortex and basal ganglia, seems to be the indication of the possibility of improvement and all intensive care facilities must be implemented to maximize the chances of recovering the patient. CONCLUSION In children, cytotoxic edema, even in the case of extensive involvement and significant decrease of the apparent diffusion coefficient, if confined to the white matter may be followed by a good neurological recovery. The white matter damage with the involvement of the gray matter seems to be a poor prognosis. Keywords Hypoxia, diffusion, prognosis CO.04.06 CONVENTIONAL MAGNETIC RESONANCE IMAGING IN THE DIFFERENTIATION BETWEEN HIGH AND LOW GRADE BRAIN TUMOURS IN PAEDIATRIC PATIENTS L. Porto1, A. Jurcoane1, D. Schwabe2, E. Hattingen1 1

Goethe University, Neuradiology Department, Frankfurt, Germany, Goethe University, Pediatric oncology Department, Frankfurt, Germany

2

PURPOSE It has been described that hyperintensity in diffusion weighted imaging (DWI) correlates with high-grade tumours and high signalintensity in T2-weighted (T2w) images identifies low grade tumours. We aimed to

S52 investigate the potential of routine conventional MRI sequences, such as DWI and T2-w to pre-operatively distinguish between low-grade and high-grade brain tumours in paediatric patients. METHODS Two raters, blinded to the histological diagnosis, rated the aspect and signal intensity of MR images (T2w and DWI) from 37 children with newly diagnosed brain tumours. Histological diagnoses included 18 low-grade and 19 high grade brain tumours. RESULTS The interrater agreement was 81-95 %. High grade tumours were never hypointense on DWI and low grade tumours were usually hyperintense on T2w. Specificity was 100 % for low-grade tumours and 90 % for high-grade tumours. About 95 % of the high-grade tumours and about 70 % of the low-grade tumours were correctly diagnosed. CONCLUSION The combination of general morphological aspect of the tumours and signals on T2-w and DWI yield a high accuracy of pre-operative differentiation between low-grade and high-grade paediatric tumours. More sophisticated and time-consuming MR methods should be measured at the high diagnostic potential of conventional MRI. Keywords Brain tumours, children, MRI CO.04.07 VALUE OF 18 F-DOPA PET/MRI FUSION IN PEDIATRIC PATIENTS WITH SUPRATENTORIAL INFILTRATIVE ASTROCYTOMAS G. Morana1, A. Piccardo2, M.L. Garre'3, M. Puntoni4, P. Nozza5, A. Cama6, D. Zefiro7, M. Cabria2, A. Rossi1 1 Istituto G. Gaslini - U.O.Neuroradiologia, Genova, Italy, 2Ospedali Galliera - S.C Medicina Nucleare, Genova, Italy, 3Istituto G. Gaslini U.O.Neuro-oncologia, Genova, Italy, 4Ospedali Galliera - Direzione Scientifica, Genova, Italy, 5Istituto G. Gaslini - U.O. Anatomia Patologica, Genova, Italy, 6Istituto G. Gaslini - U.O. Neurochirurgia, Genova, Italy 7Ospedali Galliera -S.C. Fisica Sanitaria, Genova, Italy

PURPOSE To investigate the diagnostic role, clinical contribution, and prognostic value of fused 18 F-DOPA PET/MRI images in pediatric supratentorial infiltrative astrocytomas (IAs). METHODS Pediatric patients with supratentorial IAs involving at least two cerebral lobes, either newly diagnosed or with suspected disease progression, prospectively underwent 18 F-DOPA PET and conventional MRI, performed within ten days of each other. 18 F-DOPA-PET data were interpreted qualitatively and semiquantitatively, fusing images with MRI. Maximum standardized uptake values (SUVmax), tumor-tonormal contralateral tissue (T/N) ratios and tumor-to-normal striatum (T/S) ratios were calculated for all tumors. Correlations between the degree and extent of 18 F-DOPA uptake, MRI tumor characteristics, and histologic results were investigated. The contribution of 18 F-DOPAPET/MRI fusion was considered relevant if it enabled one to: i) select the most appropriate biopsy site; ii) discriminate between disease progression and treatment-related changes; and iii) influence treatment strategy, supplementing the role of MRI and histology. Patient’s outcome was finally correlated with DOPA uptake. RESULTS 13 patients (8 boys and 5 girls) were included (5 diffuse astrocytomas, 2 anaplastic astrocytomas, 5 gliomatosis cerebri, and 1 glioblastoma multiforme). The DOPA uptake pattern was heterogeneous in all positive scans (9/13), revealing metabolic heterogeneities within each tumor. Significant differences in terms of DOPA uptake were found between low- and high-grade lesions (p<0.05). The diagnostic and therapeutic contribution of 18 F-DOPA PET/MRI fusion was relevant

Neuroradiology (2013) 55 (Suppl 1):S15–S159 in 9 out of 13 patients (69 %). DOPA uptake correlated significantly with progression free survival (p=0.004) CONCLUSION Our results indicate that 18 F-DOPA PET/MRI fusion may be a reliable imaging biomarker of IAs. Close collaboration between neuroradiologists and nuclear medicine physicians is required to improve such process of the integration of information obtained by different imaging modalities (multimodal imaging), in order to possibly overcome their individual limitations and/or to better extrapolate subtle diagnostic data that might be useful for optimal treatment strategy. Information gathered by this combined imaging approach can be readily transferred to the everyday practice and may help clinicians to better stratify patients with IAs, especially diffuse astrocytomas and gliomatosis cerebri, for diagnostic, therapeutic and prognostic purposes. Keywords 18 F-DOPA PET, brain tumor, MRI CO.04.08 MR IMAGING FINDINGS IN PEDIATRIC HEAD AND NECK RHABDOMYOSARCOMA I. Delgado Alvarez, J.L. Hortega Garcia, A. Sanchez Montanez, L. Gros Subias, E. Vazquez Mendez Hospital Universitario Vall D'Hebron, Barcelona, Spain PURPOSE Rhabdomyosarcoma is the most common soft-tissue tumor in children and 40 % of them occur in the head and neck region. Magnetic Resonance imaging is actually the technique of choice for investigation in patients with head and neck tumors. In this pictorial review we illustrate the spectrum of presentations of craniofacial rhabdomyosarcoma (RMS) in children, show the characteristic MR imaging findings, discuss the role of the advanced MRI techniques and present the differential diagnosis of RMS. METHODS Twenty-two children (aged 1-13y) with RMS seen in our pediatric center between 2007 and 2013 were retrospectively reviewed. An analysis of their MR imaging findings are presented in an educational approach. Other entities involving pediatric head and neck are presented in the differential diagnoses. Routine spin-echo (SE) T1- and T2-weighted sequences before and after intravenous contrast administration in axial, coronal and/or sagittal planes were performed. Fat saturation was added in contrastenhanced series. Diffusion-weighted imaging (DWI) was included in all studies. 1,5 T Siemens machine was used and patients under 5 years were sedated. RESULTS Based on primary location, RMS were classified as: parameningeal (nasal cavity, paranasal sinuses, middle ear, pterygopalatine fossa… ), nonparameningeal (pharynx, oral cavity…) and orbital. Nasopharyngeal carcinoma, lymphoma, Langerhans cell histiocytosis, Ewing sarcoma, metastasis and fibrous dysplasia have been included in the differential diagnosis. CONCLUSIONS Rhabdomyosarcoma is the most common soft-tissue tumor in children and 40 % of them occur in the head and neck region. MR imaging plays an important role in the evaluation of head and neck tumours in the paediatric population. Advanced MRI techniques (DWI) is useful in de differential diagnosis and in the discrimination between residual viable and non-viable tumour masses. Keywords Rhabdomyosarcoma, MRI, children

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CO.04.09 AUDIO-VISUAL REAR-PROJECTION SYSTEM IN MAGNETIC RESONANCE FOR PEDIATRIC POPULATION A. Sanchez-Montanez, I. Delgado, J.P. Salazar, J.F. Corral, E. Vazquez, G. Enriquez Vall D'Hebron University Hospital - Diagnostic Imaging, Barcelona, Spain PURPOSE -To reduce movements of children improving image quality -To reduce scan times allowing a greater number of explorations -To avoid or minimize number of sedations reducing costs -To allow performing MR in non-candidates patients for sedation -To improve patient comfort by reducing the claustrophobic feeling -Availability for visual and auditory functional MRI METHODS We have been studying the benefits of our developed audio-visual rearprojection (AVRP) system that works in 1.5 and 3 T Magnetic Resonance for two years in our institution at The Vall d’Hebron University Hospital. The system consists of: -DVD-DVD player, Movies, Projector (outside the room) -Display and Cranial coil-mirrors (inside the room) -Audio-system (both outside and inside the room) RESULTS In our clinical practice, the group of patients considered 'uncooperative' represents about 50 %. These patients require sedation depending on the anesthesiologist’s availability, patient's respiratory status, and parental consent, among other factors. AVRP system has been demonstrated as a very useful tool in the 1.5 and 3 T MRI to improve image quality, as patients remain still over the duration of the scan, with less need to repeat sequences, reducing scanning times. It also minimizes claustrophobic feelings of anxiety and discomfort, avoiding to practice sedation for MRI in these cases. Furthermore, it has been observed a significant reduction in the number of sedation in children age limit. Similarly, patients with medical contraindications for sedation such as patients with lung problems who had to be studied with CT, now take advantage of MRI thus, preventing the undesirable intrinsic effect of ionizing radiation. Additionally AVRP system opens the door to functional MR evaluation of primary auditory and visual areas. Finally, AVRP system has a very low cost of implementation, an ease of use and involves a not inconsiderable cost reductions enabling the potential realization of a larger number of studies in a lesser time, requiring less personnel and equipment for sedation. CONCLUSIONS The AVRP system has proven very useful for the practice of MRI in pediatric population. It has demonstrated significant benefit to children as young as 3 years of age in completing an interpretable brain MR exam without sedation/anesthesia. Keywords Comfort and support procedure, sedation, pediatrics

S53 Beaumont Hospital - Department of Academic Radiology, Dublin, Ireland PURPOSE CT-guided bone biopsy is advocated as a useful tool to aid in the diagnosis and management of suspected vertebral malignancies and infection. However, there is limited data available to support this practice. This single institution retrospective study aims to provide evidence to inform the discussion and debate over the usefulness of image-guided bone biopsy for spinal pathology. METHODS All 26 CT-guided bone biopsies of the spine at Beaumont Hospital Dublin, a tertiary referral centre for neurosurgery, orthopaedics and oncology, from April 2009 to April 2013 inclusive were examined. Information pertaining to the biopsy technique and biopsies themselves as well as the indications, treatment plans, and clinical courses of the patients involved were collected. Alterations in management and the need for further investigations based on the histopathological results of these biopsies were scrutinised. The study design was that of a retrospective chart review. RESULTS Of the 26 biopsies performed during the study period: 22 were performed for clinically or radiologically suspected cases of primary carcinoma or metastasis; 2 for suspected discitis; 1 for a mass of unknown origin; and 1 which was lost to follow-up and therefore excluded from this study. Following histopathological examination: 15 of the remaining 25 biopsies were diagnostic (60 %). Ten were non-diagnostic (40 %), and this group includes 4 repeat CTguided biopsies. Factors related to this included small sample obtained and difficulty with accessing radiological abnormality during the CTguided biopsy procedure. Of the 15 biopsies which were diagnostic, 13 (87 %) resulted in a significant change in patient management. The other 2 were diagnostic of non-neoplastic tissue which was borne out on subsequent clinical and radiological follow-up. In summary, 13 biopsies (52 %) resulted in a change of the patient’s management on the basis of the histopathological diagnosis. CONCLUSION This study shows the potential complementary and effective role that minimally-invasive percutaneous CT-guided biopsy can play in guiding the diagnosis and management of abnormal spinal pathology. However, a significant number of patients have a non-diagnostic result and may require open surgical or other type of biopsy. Keywords CT-guided, spinal biopsy, diagnostic tool S.28.02 BONE MINERAL DENSITY MEASUREMENTS OF THE SPINE DERIVED FROM SAGITTAL REFORMATIONS OF MDCT J. Bauer1, T. Baum2, C. Zimmer1 1 Dep. of Neuroradiology TUM, Munich, Germany, 2Dep. of Radiology, Munich, Germany

MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 5 15:00–16:30 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - SPINE S.28.01 EFFICACY AND UTILITY OF CT-GUIDED SPINAL BIOPSY AS A DIAGNOSTIC TOOL R. Brennan, A. O'Hare, J. Thornton, P. Brennan, S. Looby

OBJECTIVES To assess quantitative computed tomography (QCT) equivalent bone mineral density (BMD) of the lumbar spine in sagittal reformations of standard, non-calibrated MDCT with simple PACS measurement tools and to apply this method to MDCT datasets for differentiating patients with and without osteoporotic vertebral fractures. METHODS A MDCT-to-QCT conversion equation for lumbar BMD measurements was developed by using 35 corresponding vertebrae in 15

S54 postmenopausal women (68 ±8 years), who underwent standard QCT and non-enhanced MDCT of the lumbar spine within 2weeks. QCT was performed in semi-axial slices in L1-L3 using a calibration phantom. The sagittal reformations were used for corresponding lumbar Hounsfield-unit(HU) measurements in MDCT. Different equations were established for MDCT examinations using 120 kV and 140 kV, respectively. The MDCT-to-QCT conversion equation was applied to lumbar MDCT scans of 58 age-matched postmenopausal women (70 ± 10 years) with and without osteoporotic fractures. Their vertebral fracture status was assessed in the sagittal reformations. RESULTS A correlation coefficient of r =0.94 (p<0.001) was calculated for the MDCT with 120 kV using the conversion equation BMD(QCT==0.75xHU(MDCT_120)mg/ml. For 140 kV, a correlation coefficient of r=0,86 (p<0.001) was found using the conversion equation BMDQCT=0.9xHU(MDCT_140)mg/ml. Patients with existing osteoporotic fractures showed significantly (p<0.001) lower converted BMD values (BMD=52 mg/ccm; averaged over L1-L3) than patients without fracture (BMD=92 mg/ccm). CONCLUSION In modern MDCT scanners, a close relationship between HU and calibrated BMD exists. Thus, a patient’s BMD can easily be determined from any non-contrast-enhanced MDCT scan without phantom calibration and help the neurosurgeon in planning spine surgery. Keywords Spine, quantitative CT, osteoporosis S.28.03 IMPROVING THE ACCURACY OF TRANSPEDICULAR SCREW PLACEMENT IN THE LUMBAR SPINE WITH 3-D STER EOTA CTIC NAV IGATION : A R EVIEW O F 518 CONSECUTIVE PATIENTS A. Bourgeois, A. Faulkner, J. Gash, W. Reid University of Tennessee Medical Center, Knoxville, TN, USA PURPOSE Over the past 10 years, advanced image guidance systems have achieved increased utilization in transpedicular screw placement. Threedimensional (3-D) stereotactic navigation utilizing intraoperative computed tomography (CT) aims to reduce operative morbidity by increasing the accuracy of percutaneous pedicle screw placement (PPSP). We present the accuracy data from a consecutive series of 599 patients who underwent lumbar fusion including transdpedicular screw placement aided by 3-D navigational guidance. To the authors’ best knowledge, this represents the largest single operator study of its kind. METHODS 599 patients had placement of a combined 2438 pedicle screws by either minimally invasive transforaminal or posterior approach. All lumbar pedicle screws were placed utilizing the 3-D image guided Sextant system (Medtronic, Inc.). Of these, 518 patients had post-procedural imaging and clinical follow-up. Postoperative CT images were evaluated for incidence, direction, and distance of pedicle breach. A total of 2123 pedicle screws were evaluated. RESULTS Of the 2123 pedicle screws reviewed, 7 breaches were present. 5 were 3–4 mm and 2 were 1-2 mm (5 medial, 2 lateral). One patient of 599 required postoperative screw revision due to clinically symptomatic breach (0.16 %). The breach rate was 0.3 % (7 in 2123). When compared to a meta-analysis of 964 patients that underwent thoracolumbar PPSP aided by 2-D navigational guidance, the rate of breach ratio was 0.13 (95 % CI=0.06 - 0.29, p<.001). This corresponds to an 87 % reduction in breach risk in the 3-D navigation group.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSION Intraoperative fluoroscopic systems that produce multiplanar CT-like imaging combined with image guidance systems provide a highly accurate technique for the percutaneous placement of lumbar pedicle screws. We propose that a single operator using 3-D navigational guidance can achieve pedicle screw placement accuracy as close to 100 % as reasonably attainable in medicine. The presentation will include a focused discussion of the instrumentation and surgical techniques utilized in pedicle screw placement and provide practical insight for understanding post-operative lumbar spine imaging. Keywords Spine surgery, neuronavigation, pedicle screws MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 6 15:00–16:30 PARALLEL SCIENTIFIC SESSION WITH INTRODUCTORY INVITED PRESENTATION - HEAD AND NECK S.29.01 ACUTE TENSION ORBITAL EMPHYSEMA: MECHANISM AND TREATMENT WITH NEEDLING DECOMPRESSION A. Simonovich1, S. Levartovsky2, W. Wehbby2, E. Aloni2 1 Barzilai Medical Center, Radiology Department, Faculty of Sciences at the Ben Gurion University of the Negev, Israel, Ashkelon, Israel, 2Barzilai Medical Center, Ophthalmology Department, Faculty of Sciences at the Ben Gurion University of the Negev, Israel, Ashkelon, Israel

INTRODUCTION Orbital emphysema is a common finding following orbital wall fractures. On general, it is a benign finding and no treatment is required. On rare cases acute tension orbital emphysema (pneumo-orbit) might occur causing acute orbital compartment syndrome leading to visual loss. PURPOSE We will present a patient with severe acute tension orbital emphysema in whom drainage of air was performed by a simple technique. The mechanism by which it was derived will be presented. MATERIAL AND METHODS A 61 year old female was struck in her right eye by an airbag during a road accident. She had decreased vision in her left eye mainly due to a submacular and macular hemorrhage. On orbit CT two medial wall fractures and one inferior wall fracture with few orbital small air bubbles were seen. Thirty six hours following trauma, after sneezing, the patient complained of severe left orbital pain and on examination there was severe left eye proptosis, a frozen globe with no eye movements and an afferent pupillary defect that was not seen previously. Orbit CT showed acute tension orbital emphysema. An immediate lateral canthotomy and lower lid cantolysis improved her symptoms only mildly. Drainage of air was performed by insertion of a 22 gauge needle to the inferior retrobulbar air compartment. Video Recording of the maneuver will be presented. RESULTS Although immediate improvement in proptosis and eye movements and partial improvement of the afferent pupillary defect were seen, visual acuity did not improve due to optic neuropathy and macular scaring. CONCLUSIONS It is essential to recognize early these rare cases of acute tension orbital emphysema that may cause vascular compromise due to orbital compartment syndrome and thus may lead to optic neuropathy or central retinal artery occlusion. Needle drainage of acute severe orbital emphysema is a simple and safe procedure that may prevent visual loss. It is a unique treatment only suitable for orbital compartment syndrome due to orbital emphysema. Keywords Trauma, orbit, CT

Neuroradiology (2013) 55 (Suppl 1):S15–S159 S.29.02 COMPARISSON OF ECHO-PLANAR DIFFUSION-WEIGHTED MRI AND HIGH-RESOLUTION CT IN THE STUDY OF PEDIATRIC CHOLESTEATOMA A. Sanchez-Montanez1, J.P. Salazar1, F. Pumarola2, I. Delgado1, M. Pellicer2, E. Martinez3, E. Vazquez1 1

Vall D'Hebron University Hospital, Diagnostic Imaging, Barcelona, Spain, 2Vall D'Hebron University Hospital, ENT Surgery, Barcelona, Spain, 3Vall D'Hebron University Hospital, Pathology Department, Barcelona, Spain PURPOSE The purpose of this study is: - To evaluate the use of Echo-Planar DWI in the diagnosis of cholesteatoma in pediatric population. - To compare results and imaging findings with High-Resolution CT (HRCT) with bone window. METHODS Retrospective review of pediatric cases with echo-planar DWI (1.5 and 3 T) for cholesteatoma evaluation, from January 2011 to March 2013. A review of the ENT medical history was carried out, analysing imaging findings and radiological reports of cases evaluated by pediatric neuroradiologist with the corresponding pathology reports. Correlation between imaging findings on DWI with HRCT was done. RESULTS 32 cases were identified between 4 and 17 years-old. DWI depicted a positive result for cholesteatoma in 17 of these 32 cases, while 15 were negative. Out of these 17 children with cholesteatoma by DWI, 8 were positive according to the pathology report and 8 according to ENT surgeon. There was only one case with positive DWI and negative pathology report. 19 cases (59,4 %) had been evaluated with both high-resolution CT and DWI for cholesteatoma, while 13 cases were studied using DWI without HRCT. 5 of 10 patients (50 %) with positive results for cholesteatoma on DWI had also positive results in HRCT, while 4 of 9 cases with negative DWI (44 %) had also negative HRCT. In general, the concordance between CT and DWI was 52,6 %. 17 patients had DWI and pathology report. Among them 94,1 % were both positve. There was one case (5,8 %) with cholesteatoma by DWI but negtive pathology result; therefore sensitivity was 100 % and the PPV 94 %. HRCT only identified 5 of 10 positive cases by pathology, therefore its sensitivity was 50 % with 5 false negative results. CONCLUSIONS DWI-MRI is a fundamental tool in cholesteatoma diagnosis; however, it is still a complementary diagnostic imaging option. The overall concordance between DWI AND HRCT in this study was 52,6 %. Cholesteatoma might be present even without bone erosion, which is one of the key findings on HRCT . This shows the importance of using DWI independently of HRCT results. We have demonstrated in this study that DWI could be used for the initial diagnosis and follow-up of cholesteatoma, reducing radiation exposure. Keywords Cholesteatoma, diffusion weighted-image, pediatrics S.29.03 DIAGNOSTIC VALUE OF 3TESLA HIGH RESOLUTION IMAGING OF THE TEMPORAL BONE IN CI CANDIDATES P. Raab1, F. Götz1, S. Lyutenski2, E. Bültmann1, T. Lenarz2, H. Lanfermann1, A. Giesemann1

S55 1 2

Hannover Medical School, Neuroradiology, Hannover, Germany, Hannover Medical School, Departement of ENT, Hannover, Germany

PURPOSE to evaluate the possibilities of a 3Tesla FSE VFA sequence with the use of a loop coil in the clinical setting with cochlea implant candidates. METHOD A high resolution imaging sequence (T2-VFA TSE sequence, voxel size 0.39x0.39x.2, FOV 200, scanning time 10:16 min) was used additionally in 53 children undergoing pre-cochlea implant evaluation (including standard protocol T2-VFA TSE Sequence, voxel size 0.52x0.52x0.4, scanning time 4:58 min). In these 53 children 10 were examined bilateral, resulting in 63 examined ears. Due to not sufficient image quality 9 were discarded. Out of the remaining 54 exams 9 ears presented with suspected nerve hypoplasia/ aplasia, 14 presented with inner ear malformations (5 Incomplete partition Typ 1, 3 Incomplete partition Typ 2, 2 aplasia of the semicircular canals, 2 dysplasia of the semicircular canals, 1 hypoplastic cochleae and 1 large vestibular aqueduct syndrome) and 2 with an atresia of the external auditory canal. Image evaluation and comparison was done by three neuroradiologists with 6, 10 and 11 years of experience. Imaging features as the continuity of the cribiform plate, the modiolus, the cochlear nerve, the visibility of the cochlear duct and the utriculus were evaluated. Diagnostic advantages over the lower resolution images were noted. RESULTS The presentation of the stuctures was as follows: the cribiform plate was complete in 46 cases and incomplete in 8. The Modiolus was complete in 39 cases, partial existent in 10 and absent in 5 ears. The cochlear nerve was hypoplastic or aplastic in 9 cases. The cochlear duct was not seen clearly in any case and the Utriculus was appearing blurred in 12 cases compared to the others. Most diagnostic benefit was noted in cases of cochlear nerve hypoplasia or aplasia, CONCLUSION The use of a loop coil in combination with a high resolution 3Tesla FSE VFA sequence reveals a benefit for the diagnosis of cochlea nerve hypoplasia or aplasia. Keywords Temporal bone, cochlea implant, high resolution S.29.04 NEW PRE-SURGICAL GRADING SYSTEM FOR ACTIVE MIDDLE EAR IMPLANTS IN PATIENTS WITH CONGENITAL AURAL ATRESIA C. Mohr1, G. Sprinzl2, G. Widmann3, D. Petersen1, B. Wollenberg4, H. Frenzel4 1

Institute of Neuroradiology, University Hospital Schleswig-Holstein Lübeck, Lübeck, Germany, 2Department of Otorhinolaryngology, University Hospital Innsbruck, Innsbruck, Austria, 3Department of Radiology, University Hospital Innsbruck, Innsbruck, Austria, 4 Department of Otorhinolaryngology and Facial Plastic Operations, University Hospital Schleswig-Holstein Lübeck, Lübeck, Germany PURPOSE Active middle ear implants (aMEI) can be used for hearing restoration in congenital aural atresia and other malformations of the middle ear. To date the existing scores and grading sytems used for pre-surgical CT findings in malformed middle ears do not exactly meet the requirements for these implants. Some items are expendable and others are completely missing. Our purpose was to design a new grading system that can describe the extent of the malformation and also predict the feasibility and surgical complexity of implanting an aMEI. METHODS Therefore we evaluated more than one hundred temporal bone HRCT scans of malformed middle ears for aMEI score

S56 development. We included qualitative items such as middle ear and mastoid pneumatization, morphology of the stapes, configuration of the oval and round window, tegmen mastoideum and facial nerve displacement. An anterior- and posterior round window corridor, oval window and stapes corridor were novelly designed and quantified, describing the size of the surgical field and the sight towards the windows. RESULTS The score grades the ears on a 16-point scale (16–13 easy, 12–9 moderate, 8–5 difficult, 4–0 high risk). The strength of agreement between the aMEI score and performed implantations was good. Comparison of our new 16-point scale aMEI score with the Jahrsdoerfer score showed that both were able to conclusively detect the high-risk group. But, the aMEI score was able to further determine which malformed ears were favorable for an aMEI, which the Jahrsdoerfer score could not do. CONCLUSION The Active Middle Ear Implant Score (aMEI score) for aural atresia allows more precise risk stratification and decision making regarding the feasibility of surgical implantation of an aMEI. The use of operative corridors seems to have significantly better prognostic accuracy compared to the Jahrsdoerfer score. Keywords Active middle ear implant, congenital aural atresia, new grading system S.29.05 NASOPHARYNGEAL CANCER, A NEURORADIOLOGICAL DIAGNOSIS. HOW OFTEN IS SKULL BASE AFFECTED? B. Kress1, S. Babu2, N. Ravindranathan3, P. Varghese4, A. Gottschalk1,4 1

Institute of diagnostic and interventional Neuroradiology, Krankenhaus Nordwest, Frankfurt, Germany, 2The Brunei Cancer Center, Bandar Seri Beghawan, Brunei, 3Department of oro-maxillo-facial surgery, Ripas Hospital, Bandar Seri Beghawan, Brunei, 4Department of diagnostic Neuroradiology, Bandar Seri Beghawan, Brunei OBJECTIVE How often skull base is affected in primary staging of nasopharyngeal cancer (NPC) MATERIAL AND METHODS Between February 2011 and January 2013 35 patients underwent MR (magnetic resonance imaging) for primary staging in nasopharyngeal cancer in our department. These cases were analysed retrospectively concerning affection of skull base compartments (prevertebral space, prestyloid and poststyloid parapharyngeal space, masticator space, clivus, trigeminal nerve V2 and V3, cavernous sinus, pterygopalatine fossa and dura). Lesion was rated as affection of skull base when the lesion infiltrated one of the following compartments: clivus, dura, pterygopalatine fossa, Trigeminal nerve V2 and V3 and cavernous sinus. RESULTS 10 women and 25 men shows an average of age of 51 (15–69years). 1 patient was staged as T1 (3 %), 10 patients as T2 (29 %), 5 patients as T3 (14 %) and 19 patients as T4 (54 %). In 18 cases (51 %) at least one skull base compartment was affected: N. V2 8 patients (23 %), N. V3 6 patients (17 %), pterygopalatine fossa 11 patients (31 %), cavernous sinus 9 patients (26 %), clivus 17 patients (49 %), dura 7 patients (20 %). CONCLUSION In primary staging of NPC 51 % of patients showed an infiltration of the skull base. Especially the affection of cranial nerve and pterygopalatine fossa requires profound MR anatomical knowledge, which is present in neuroradiologist or specialised head and neck radiologists only. Affection of skull base in NPC

Neuroradiology (2013) 55 (Suppl 1):S15–S159 changes therapeutic options (f.e. enlargement of radiation field), therefore it is mandatory that MR staging of NPC should be done in Institutes with dedicated neuroradiological or head and neck expertise only. Keywords NPC, MR, skull base S.29.06 HIGH-RESOLUTION DIFFUSION-WEIGHTED IMAGING USING READOUT-SEGMENTED ECHO-PLANAR IMAGING IN THE DIAGNOSIS OF TEMPORAL BONE ESPECIALLY FOR MIDDLE EAR CHOLESTEATOMAS T. Kodama1, T. Yano1, S. Tamura1, D. Porter2 1 Faculty of Medicine, University of Medicine, Department of Radiology, Miyazaki, Japan 2Siemens AG, Healthcare Sector, Erlangen, Germany

PURPOSE The usefulness of diffusion weighted imaging (DWI) in the evaluation of cholesteatomas has been widely recognized. However, DWI using standard single-shot echo-planar imaging (ss-EPI), is vulnerable to susceptibility artifacts even with parallel imaging, especially at 3 T. Readout segmented EPI (rs-EPI) has been suggested as a promising variant to EPI for high-resolution imaging with less image distortion and susceptibility artifacts. This study aimed to evaluate the utility of DWI using rs-EPI in the diagnosis of middle ear cholesteatomas. METHODS This prospective study was approved by the medical ethics committee of our institution with written informed consent. DWI was performed using rs-EPI, ss-EPI and 3D-PSIF (reversed FISP) on a 3 T MRI system in 39 patients with temporal bone pathologies including 33 cholesteatomas. Measurement parameters for the rs-EPI DWI acquisition were determined based on fundamental studies as follows; TR=6500 msec, TE=70 msec, b=0 and 3 orthogonal diffusion directions with b=800 sec/mm2, FOV=220 mm, matrix size=226 X 226, slice thickness=1.5 mm, number of readout segments=11, acceleration factor of GRAPPA=2, averaging=1, and a scan time of 6 min 6 sec. The image data were visually assessed to evaluate image properties (such as signal-to-noise ratio, spatial resolution, geometric distortions and susceptibility artifacts), as well as lesion conspicuity, and diagnostic confidence. Apparent diffusion coefficient (ADC) maps were obtained from the rs-EPI and ss-EPI data and ADCs were compared in 24 cholesteatomas. RESULTS Compared with ss-EPI DWI, rs-EPI DWI showed better image quality and lesion conspicuity in almost all patients by reducing geometric distortions, susceptibility artifacts, and image blurring, in spite of its lower signal-to-noise ratio. However, rs-EPI DWI was not completely free from susceptibility artifacts and its overall diagnostic utility was lower than PSIF DWI in 16 patients. In particular, two small cholesteatomas were only visualized on 3D PSIF DWI. Although the ADCs of the cholesteatomas from rs-EPI and ss-EPI were well correlated, ADCs derived from rs-EPI (0.78 +/− 0.11) were slightly but significantly lower than ADCs derived from SS-EPI (0.82 +/− 0.11). All cholesteatomas showed an ADC value lower than 1.2 X 103/mm2/sec. CONCLUSIONS rs-EPI DWI provided higher image quality and lesion conspicuity than rs-EPI and ADCs obtained by both EPI techniques were well correlated. However, rs-EPI DWI was still more susceptible to susceptibility effects than non-EPI DWI. Keywords Cholesteatoma, diffusion weighted imaging, readout segmented DWI

Neuroradiology (2013) 55 (Suppl 1):S15–S159 MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 3 15:00–16:30 PARALLEL SCIENTIFIC SESSION - BRAIN TUMORS 2 CO.05.01 PREOPERATIVE DIFFERENTIATION OF HIGH GRADE GLIOMAS, METASTASES AND PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMAS USING PERFUSION AND DIFFUSION WEIGHTED MR IMAGING A. Zimny, M. Neska-Matuszewska, J. Bladowska, M. Guzinski, M. Sasiadek Wroclaw Medical University, Department of Radiology, Wroclaw, Poland PURPOSE In standard MR examination high grade gliomas (HGG), metastases (meta) and primary central nervous system lymphomas (PCNSL) may show very similar appearance. The aim of the study was to evaluate usefulness of perfusion (PWI) and diffusion (DWI) weighted imaging in the preoperative diagnostics of these tumours. METHODS The study group consisted of 20 patients with HGG, 20 with meta and 9 with PCNSL. In PWI parameter of Cerebral Blood Volume (rCBV) and shape of perfusion curves (parameters: rPH-peak height, rPSR- percentage of signal recovery) and in DWI diffusion coefficient (ADC) were analyzed. These parameters were assessed from the tumour core and peritumoural non enhancing T2 hyperintense region. RESULTS Within tumour core HGG and meta showed similar high rCBV values (5.05 and 4.95, respectively) while PCNSL showed significantly lower rCBV values (0.68) and rPSR (1.95). Analysis of ADC from the tumour core revealed similar high values for HGG and meta (1.14x10-3, and 1.15x10-3) and significantly lower for PCNSL (0.59x10-3). In the peritumoural region HGG showed significantly higher values of rCBV compared to meta (1.4 and 0.45, respectively), without any differences in ADC values (1.25x10-3 and 1.65x10-3, respectively). CONCLUSIONS Analysis of PWI and DWI parameters enables to differentiate PCNSL from HGG and metastases. PCNSL are hypoperfused tumours with typical perfusion curve returning above the baseline levels and with diffusion restriction. The analysis of the peritumoural region is useful in distinguishing between metastases and HGG, the latter are surrounded by edema and infiltration leading to higher rCBV values. Keywords Brain tumours, perfusion weighted imaging, diffusion weighted imaging CO.05.02 COMPARISON OF THREE DIFFERENT MR-PERFUSION TECHNIQUES AND MR-SPECTROSCOPY FOR DISTINGUISHING RECURRENT HIGH-GRADE GLIOMAS FROM RADIATION INJURY A. Seeger1, C. Braun2, F. Paulsen3, M. Skardelly4, U. Ernemann1, S. Bisdas1 1

Diagnostic and Interventional Neuroradiology, Tuebingen, Germany, Department of Neurology, Tuebingen, Germany, 3Department of Radiation Oncology, Tuebingen, Germany, 4 Department of Neurosurgery, Tuebingen, Germany 2

INTRODUCTION The discrimination between recurrent tumor and post-radiation changes might be indistinguishable in conventional MRI. MR perfusion techniques and MR spectroscopy (MRS) provide additional specific

S57 pathophysiological information that may allow to separate glioma progression from post-radiation changes. METHODS 40 patients with histologically verified high-grade gliomas previously treated with surgery and radiotherapy and new enhancing lesions masses underwent conventional MRI, arterial spin labeling (ASL), dynamic contrast-enhanced T1-weighted perfusion imaging (DCE), dynamic susceptibility contrast-enhanced perfusion imaging (DSC), and multi-voxel MRS. Quantitative parameters were calculated in tumor recurrences and radiation changes, which were retrospectively reviewed based on clinical and radiological followup. The cerebral blood flow (rCBF) in ASL was calculated and normalized to white matter. The mean and maximum transfer constant between the blood plasma and extracellular space, k(trans), in DCE-MR as well as the extravascular, extracellular space v(e) were measured. Cerebral blood volume (CBV) and cerebral blood flow (CBF) in DSC were also normalized to white matter. For MRS, peak-height of N-acetylaspartate (NAA), choline (Cho), and creatine (Cr) were measured and ratios were calculated. Receiver operating characteristic curves (ROC) for each parameter were compared. RESULTS Of the 40 patients, 23 were determined to be recurrent gliomas and 17 were radiologically and clinically determined to be radiation necrosis The patient group with recurrent glioma showed higher values in all perfusion techniques (ALS, DCS, and DSC). However, differences in ASL between the two groups were not statistically significant (rCBF 2.41± 1.3 vs. 1.66± 0.5; p= 0.063) while the following parameters obtained in DCE and DCS were significantly in recurrent tumor than in readiation changes (rCBF p<0.01; rCBV p=0.01, k(trans) p=0.046). Sensitivities/specificities for the detection of recurrent lesions were: k(trans) 61.9 % / 80 %, rCBF 77.3 % / 84.6 %, and rCBV 81 % / 76.9 %. Among the parameters in MRS, Cho/Cr(n) showed the best diagnostic accuracy (p=0.014; sensitivity 70 %, specificity 78.6 %) for detecting recurrent gliomas. CONCLUSION MR-perfusion techniques and MRS are useful tools that enable improved differentiation of recurrent glioma from radionecrosis. Keywords MR-perfusion, radionecrosis, tumor recurrence CO.05.03 INTERNAL CAROTID ARTERIAL SHIFT AFTER TRANSSPHENOIDAL SURGERY IN PITUITARY ADENOMAS WITH CAVERNOUS SINUS INVASION Y. Sasagawa1, O. Tachibana1, M. Doai2, T. Akai1, H. Tonami2, H. Iizuka1 1 Department of Neurosurgery, Kanazawa Medical University, Ishikawa, Japan, 2Department of Diagnostic and Therapeutic Radiology, Kanazawa Medical University, Ishikawa, Japan

INTRODUCTION The intercarotid distance (ICD) between cavernous carotid arteries (CCAs) is an important factor for avoiding injury of the internal carotid artery during transsphenoidal surgery. The ICD between CCAs in pituitary adenoma patients is generally larger than in normal individuals. However, the movement of the CCA during transsphenoidal surgery is not known. The aim of this study is to measure the ICD between CCAs in pituitary adenoma patients before and after surgery. METHODS We reviewed 138 pituitary adenoma patients who were treated with resection via the transsphenoidal approach. The CCA diameter and the ICD between CCAs were measured from preoperative and postoperative MR images.

S58 RESULTS The CCA diameter was similar at the preoperative and postoperative time points. On the other hand, the ICD between CCAs was shorter at postoperative time point (19.4±4.5 mm) than at the preoperative time point (20.9±4.9 mm) (P=0.048). Above all, invasion type adenomas had more significant ICD change at the postoperative time point (23.8±3.8 mm) than at the preoperative time point (21.6±3.9 mm) (P=0.008). Also in multivariate analysis, cavernous sinus invasion of adenoma was independently associated with ICD contraction >2 mm (P=0.027). CONCLUSION It is important to know the change in ICD between CCAs after transsphenoidal surgery, particularly for pituitary adenomas with cavernous sinus invasion. The position of the CCA should be known before and during transsphenoidal surgery, as well before and during the second operation to avoid vascular injuries. Keywords Pituitary adenoma, intercarotid distance, transsphenoidal surgery CO.05.04 IMAGING EVALUATION OF GLIOBLASTOMA MULTIFORME (GBM) DURING TREATMENT WITH AVASTIN® (BEVACIZUMAB) – A DIVERSITY OF FINDINGS YET TO BE UNDERSTOOD M. Sarpi, T. Lyra, L. Godoy, D. Delgado, M. Docema, H. Lee, M. Martin, L. Silva Hospital Sírio Libanês, São Paulo, Brazil PURPOSE To depict the variety of imaging findings observed in GBM follow up during the treatment with Avastin® (bevacizumab), and to discuss their possible correlation with molecular, biochemical and genetic characteristics of the tumor. METHODS We will use clinical cases with magnetic resonance imaging (MRI) to discuss correlation between the imaging findings (before and after treatment) and molecular, biochemical and genetic characteristics of GBM, supported by literature review. To demonstrate through MRI the tumor behavior during target therapy, depicting different patterns of evolution and growth of the lesions, sometimes different from the initial tumor and present in the same patient. RESULTS The use of target therapy for recurrent GBM is recent and it extends the life span, but does not cure the disease. The effects on tumor behavior and growth pattern are still being observed and understood, and we will demonstrate possible presentations using confirmed cases with diverse imaging features and clinical data, such as time in therapy. CONCLUSIONS Avastin® (bevacizumab) was approved in 2009 by the FDA for the treatment of GBM patients with progressive disease following prior therapy. It is an inhibitor to the activity of human vascular endothelial growth factor and represents a promising optional treatment for these patients, since angiogenesis is a hallmark of high grade tumors (specially GBM). Imaging evaluation of the treatment effects is very interesting – tumors initially responds, but ultimately progress, and it is possible to observe distinct imaging patterns of growth, sometimes multiple in the same patient. As a relatively recent practice there will be a lot to observe and to learn regarding tumor behavior related to this treatment, and imaging is playing a fundamental role in the evaluation of response and prognostic factors. Keywords Glioblastoma multiforme (GBM), Avastin® (bevacizumab), imaging follow-up

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CO.05.05 MRI FEATURES OF MULTIFOCAL AND MULTICENTRIC GBM TO AID DIFFERENTIATION FROM CEREBRAL METASTASES AND PRIMARY CNS LYMPHOMA E. Ryan, N. Adams, P. Brennan, M. Thornton, A. O'Hare, S. Looby Department of Neuroradiology, Beaumont Hospital, Dublin, Ireland PURPOSE Multifocal or multicentric glioblastoma multiforme (MGBM) is an uncommon clinical entity with imaging features similar to other cerebral tumours, particularly cerebral metastases and primary CNS lymphoma. We sought to compare MRI imaging features of a cohort of patients with MGBM with features in patients with multifocal brain metastases (MBM) and patients with multifocal CNS lymphoma (MFL). METHODS Imaging and histopathology of 25 consecutive patients with MGBM, 25 consecutive patients with MBM and 25 with MFL were retrospectively recruited from an internal neuroscience database. MRI and neuropathology were reviewed by neuroradiology and neuropathology subspecialists. Multiple MRI characteristics were evaluated, with the reviewing radiologist blinded to the tumour histology. RESULTS Age and sex demographics were similar for all 3 groups. The average number of masses at presentation was 4.9 for MGBM, 3.4 for MM and 5.1 for MFL. Masses were more commonly unilateral in MGBM (70 %) than MBM (30 %) and MFL (10 %). Identical signal characteristics for all lesions was demonstrated in all patients with MFL, versus 20 % of MGBM and 30 % of MFL. Masses were more frequently T1-hypointense in MGBM (83.7 %, n=123 masses). In cases of MBM, 49 % showed T1-hypointensity and 51 % T1-isointensity (n=85 masses). 100 % of MFL masses were T1isointense (n=78 masses). Restricted diffusion was more common in MFL (68 %) than in MGBM (0.04 % with avid DR, 35 % with partial DR) or MBM (32 %). 97 % of MFL masses demonstrated diffuse enhancement whereas rim enhancement surrounding central necrosis was present in the majority of MGBM and MBM masses (63 % and 74 % respectively). A potential pathway of dissemination along white matter tracts was demonstrated for 100 % of MGBM but was not apparent in any cases of MFL or MBM. CONCLUSION Multifocal GBM is uncommon and can be difficult to distinguish from multifocal CNS lymphoma and multiple brain metastases by standard imaging characteristics. Advanced MRI techniques including MR perfusion have shown promising potential for lesion characterisation, however we demonstrate useful conventional imaging characteristics and location patterns. In particular, an identifiable potential route of white matter tract dissemination appears to differentiate MGBM from other multifocal enhancing masses. Keywords Multifocal GBM, MRI CO.05.06 GROWTH PATTERNS OF GLIOBLASTOMA: COMBINED VISUALIZATION OF ADC DIFFUSION MAPS AND CBV PERFUSION MAPS A. Radbruch1, K. Deike1, M. Graf2, C. Reimer1, B. Wiestler3, R. Floca2, W. Wick3, M. Bendszus1, S. Heiland1 1 University of Heidelberg, Department of Neuroradiology, Heidelberg, Germany, 2German Cancer Research Center, Department of Radiology, Heidelberg, Germany, 3University of Heidelberg, Department for Neuro-oncology, Heidelberg, Germany

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Decreased Apparent Diffusion Coefficient (ADC) values on Diffusion MRI (DWI) maps and increased Cerebral Blood Volume (CBV) values on dynamic-susceptibility-contrast weighted perfusion MRI (DSC) maps have been reported to identify areas of increased malignancy in high grade glioma. Here we analyzed if both imaging techniques identify similar areas and if a combined visualization of both imaging techniques can identify different growth patterns of glioblastoma. MATERIALS & METHODS DWI, DSC and contrast-enhanced T1-w Imaging using DOTAREM (Gadoterate meglumine) was performed in 53 patients with newly diagnosed and histologically proven glioblastoma before surgery on a 3 Tesla MR-system. ADC and CBV maps were calculated and coregistered on T1-w images. A region of interest was manually delineated on T1-w images encompassing the enhancing lesion including a 1 cm margin. Within this ROI, pixels with ADCthe 70th percentile (maxCBV) and the corresponding overlap were automatically calculated and visualized on the T1-w images. The acquired maps were assessed by two neuroradiologists and qualified as predominant DWI growth pattern if minADC values were located mainly in the surrounding area and maxCBV values were located mainly within the enhancement and as predominant CBV pattern for the opposite distribution. RESULTS MinADC- and maxCBV-areas showed an average overlap of 11.66 +/− 3.8 percent within the complete ROI. 41 patients were qualified as predominant DWI growth pattern, 7 patients as predominant CBV and 5 patients did not present any specific distribution of MaxCBV and MinADC values. CONCLUSION Our study provides evidence, that diffusion- and perfusion-imaging visualize different aspects of tumor biology that do not necessarily overlap spatially. Furthermore a possible explanation of the pathophysiologic mechanism within the majority of predominant ADC tumors could be that migrating tumorcells in the invasion-front, represented by areas of low ADC-values, produce and secrete neoangiogenic factors, leading to a trailing behind of the vascular-rich tumor border, represented by high CBV-values. Keywords Glioblastoma, diffusion imaging, perfusion imaging CO.05.07 DIFFERENTIATION OF PSEUDOPROGRESSION AND REAL PROGRESSION IN GLIOBLASTOMA USING ADC PARAMETRIC RESPONSE MAPS A. Radbruch1, C. Reimer1, M. Graf2, J. Fladt1, K. Deike1, R.O. Floca2, S. Heiland1, H.P. Schlemmer2, W. Wick3, B. Wiestler3 1 University of Heidelberg, Department of Neuroradiology, Heidelberg, Germany, 2German Cancer Research Center, Department for Radiology, Heidelberg, Germany, 3University of Heidelberg, Department of Neurooncology, Heidelberg, Germany

INTRODUCTION Pseudoprogression describes the radiologic phenomenon that patients with high-grade glioma undergoing their first or second radiation MRI show increased contrast enhancement that eventually subsides without any change in treatment. Currently it is not possible to differentiate real progression and pseudoprogression using conventional T1- and T2weighted images. Here we tested if a voxel-wise analysis of Apparent Diffusion Coefficient (ADC) values can differentiate between true progression and pseudoprogression using the parametric response map, a new postprocessing procedure.

S59 MATERIAL AND METHODS 29 patients with proven progression and 7 patients with pseudoprogression were identified in a retrospective case study. For all patients ADC baseline and follow-up maps were available. The ADC baseline map and the ADC follow up map were coregistered on the contrast enhanced T1-weighted follow up images. Subsequently the enhancement in the follow up contrast enhanced (Dotarem (Gadoterate meglumine)) T1-weighted image was manually delineated and a reference ROI was drawn in the contralateral white matter. Both ROIs were transferred to the ADC images. Relative ADC(baseline)/reference ROI(baseline) values and ADC(follow up)/reference ROI(follow up) values were calculated for each voxel within the ROI. The corresponding voxels of rADC (follow up) and rADC (baseline) were subtracted and the percentage of all voxels within the ROI that exceeded the threshold of 0.25 was quantified. RESULTS rADC voxels showed an increase of 21.9+−26.3 % above 0.25 in patients with real progression and in 55.7+− 28.3 % in patients with pseudoprogression. ROC analysis revealed a very good diagnostic performance (AUC=0.82). DISCUSSION The introduced parametric response map for rADC maps provides a potential tool for the differentiation between pseudoprogression and real progression. Generally an ADC increase is supposed to be correlated with a decrease of cellularity and hence with therapy response. Therefore our findings of an increased number of voxels with increased ADC values in patients with pseudoprogression are in line with these basic pathophysiologic considerations. Keywords Glioblastoma, parametric response MAP, diffusion CO.05.08 INTRAVOXEL INCOHERENT MOTION MR IMAGING IN GLIOBLASTOMA: COMPARISON WITH DYNAMIC SUSCEPTIBILITY CONTRAST-ENHANCED AND IMPACT ON SURVIVAL PREDICTION J. Puig1, J. Sánchez-González2, G. Blasco1, J. Daunis-I-Estadella3, M. Essig4, R. Jain5, S. Pedraza1 1 Department of Radiology (IDI), Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain, 2 Philips Ibérica, Madrid, Spain, 3 Department of Computer Science, Applied Mathematics and Statistics, Girona, Spain, 4Diagnostic Radiology and Neuroradiology, Department of Neuroradiology, University of Erlangen, Erlangen, Germany, 5 Division of Neuroradiology, Department of Radiology, Henry Ford Health System, Detroit, MI, USA

PURPOSE The degree of angiogenesis is one of the most important factors affecting the clinical outcome of astrocytomas. Dynamic susceptibilityweighted contrast-enhanced (DSC) MR imaging allows the measurement of hemodynamic parameters influenced by microvasculature, such as cerebral blood flow (CBF) or cerebral blood volume (CBV). Considering the vascular floor as a random network of vessels where blood freely flows, intravoxel incoherent motion (IVIM) MR imaging can distinguish between pure molecular diffusion and the motion of water molecules in the capillary network with a single diffusion-weighted imaging acquisition. We aimed to compare IVIM MR imaging parameters with CBF and CBF in patients with de novo glioblastomas and to determine whether IVIM parameters are useful in predicting survival. MATERIAL AND METHODS Seventeen patients (14 men; mean age, 64 years) with histologically proven glioblastoma underwent MR imaging including echo-planar imaging with IVIM-encoding gradients using 10 b values (0–1000sec/mm2). We used the IVIM biexponential model to elaborate diffusion coefficient(D), pseudodiffusion coefficient(D*), and perfusion

S60 fraction(f) maps for areas of enhanced tumor and peritumoral edema. Deconvolution of the measured tissue concentration-versus-time curve with an arterial input function was applied, and CBV and CBF maps were generated (Olea Medical,Sphere, La Ciotat, France). Pearson correlations, linear regression analysis, and intraclass correlation coefficients were determined. Receiver operating characteristic curves and Kaplan-Meier survival analysis were also conducted. RESULTS ftumor showed a close linear correlation with CBFtumor and CBVtumor (linear regression coefficients, R=0.878 and R2=0.77 [P<0.001] and R=0.599 and R2=0.36 [P=0.011], respectively). Moreover, ftumor significantly correlated with Dtumor (R=0.598, R2=0.36;P=0.011). The correlation between Dtumor and CBFtumor was R=0.561 (R2=0.31; P=0.019). The ftumor inversely correlated with D*edema(R=−0.528,R2=0.28;P=0.030). Dedema inversely correlated with CBFedema(R=−0.491, R2=0.24;P=0.053). Patients with ftumor>15.37 % had a higher risk for poor survival at seven months (AUC 0.722, 44.4 % sensitivity, 100 % specificity, 100 % positive predictive value, 100 % negative predictive value). Similarly, CBFtumor>223.01 mL/min/100 g was associated with poor outcome (AUC 0.694, 44.4 % sensitivity, 100 % specificity, 100 % positive predictive value, 100 % negative predictive value). CONCLUSIONS IVIM perfusion parameters correlate with DSC-MR imaging indexes in glioblastoma and might be suitable for assessing microvascular tumor perfusion. The ftumor seems to be a useful clinical prognostic biomarker for survival in patients with glioblastoma. Keywords Brain neoplasms, magnetic resonance imaging, perfusion MRI CO.05.09 BLOOD POOL CONTRAST AGENT MR ANGIOGRAPHY TO ASSESS GLIOBLASTOMA VASCULARITY: FEASIBILITY AND CORRELATION WITH SURVIVAL J. Puig 1 , G. Blasco 1 , J. Daunis-I-Estadella 2 , S. Remollo 1 , D. Hernández1, J. Sánchez-González3, M. Essig4, R. Jain5, S. Pedraza1 1 Department of Radiology (IDI), Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain, 2Department of Computer Science, Applied Mathematics and Statistics, University of Girona, Girona, Spain, 3Philips Iberica, Madrid, Spain, 4Diagnostic Radiology and Neuroradiology, Department of Neuroradiology, University of Erlangen, Erlangen, Germany, 5Division of Neuroradiology, Department of Radiology, Henry Ford Health System, Detroit, MI, USA

PURPOSE Glioblastoma (GBM) neovascularization, defined histologically or with molecular techniques, correlates with worse survival. However, MR angiography has been unable to characterize GBM vascularity. Gadofosveset is an albumin-binding MR contrast agent approved for imaging blood vessels. It remains largely intravascular because it forms reversible noncovalent bonds with albumin, resulting in a 4- to 5-fold increase in blood relaxivity at 1.5 T compared to extracellular contrast agents. We aimed (1) to assess the feasibility of high-resolution MR angiography using gadofosveset to detect vascularity in GBM and (2) determine whether vascularity correlates with survival. MATERIAL AND METHODS Before treatment 34 patients (23men; mean age, 63 years) with histologically proven GBM underwent MRI including T1-WI, axial FLAIR, first-pass dynamic susceptibility-weighted contrast-enhanced perfusion images, and postcontrast axial T1-WI after administration of 0.03mmol/kg gadofosveset; we obtained high resolution tumor angiography (TR,8.9 ms;TE 2.6 ms;voxel size, 0.6x0.6x0.6 mm). We obtained volumes of interest for edema, enhancing tumor, and contralateral healthy tissue. We calculated the cerebral blood volume ratio, cerebral blood flow ratio, mean permeability constant (K2), mean temporal

Neuroradiology (2013) 55 (Suppl 1):S15–S159 maximal intensity projection (tMIP), mean apparent diffusion coefficient (ADC), and T1-enhancing tumor mean volume (Olea Medical, Sphere, La Ciotat,France). Two observers assessed tumor angiograms for vascularity (hypervascular was defined when more than 3 vessels were visible); interobserver reliabilities were calculated. We did receiver operating characteristic curves and Kaplan-Meier survival analysis. RESULTS 18 (52.94 %) GBMs were classified as hypervascular and 16 (40.5 %) as hypovascular; interobserver reliability was substantial (K=0.672). In hypervascular GBMs mean tMIP values were higher (p=0.024) and there was a trend to lower mean ADC values (p=0.068). The median survival for hypovascular and hypervascular GBMs treated with surgery and with radiotherapy+chemotherapy was 15 months (95%CI,4.5-30.2) and 8.5 months (95%CI,2.9-14.1), respectively. When treatment was incomplete, the median survival for hypovascular and hypervascular GBMs was 6.5 months (95%CI,3.1-9.8) and 3.5 months (95%CI,2.1-4.9), respectively. High-resolution MR angiography pattern was the best survival predictor for GBM at 5.25 months (AUC 0.806, 81.2 % sensitivity, 77.8 % specificity, 76.5 % positive predictive value, 82.3 % negative predictive value). CONCLUSIONS High-resolution MR angiography using a blood pool contrast agent can detect vascularity in GBM. Hypervascularity correlates with worse survival. Keywords Brain neoplasms, magnetic resonance imaging, angiogenesis MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 6 1 7 : 0 0 – 1 8 : 3 0 PA R A L L E L S C I E N T I F I C S E S S I O N ADVANCED IMAGING: EPILEPSY AND CONSCIOUSNESS CO.06.01 FUNCTIONAL MRI OF PATIENTS WITH DISORDERS OF CONSCIOUSNESS L. Hermoye 1 , L. Tshibanda 2 , W. Gradkowski 1 , V. Katsaros 3 , A. Vanhaudenhuyse2, S. Laureys2 Imagilys, Brussels, Belgium, 2Liege University, Coma Science Group, Liege, Belgium, 3Athens University, Athens, Greece 1

PURPOSE In 2006 and 2010, our group published 2 groundbreaking articles (Science 2006, NEJM 2010) relating to the evaluation by functional MRI of the state of consciousness in patients with an unresponsive wakefulness syndrome (formerly known as vegetative state), minimally conscious state or locked-in syndrome. This kind of examination has not only a medical significance, but also an ethical and societal one. Seven years on, has it become a clinical tool? METHODS Since 2010, we have used MRI to examine 169 patients with disorders of consciousness. 61 of those examinations included task-based fMRI sequences, in which the patient was asked to play tennis or to walk about in his house. All of the examinations included resting-state fMRI sequences. RESULTS 11 patients presented activations in the supplementary motor area, characteristic of the motor imagery paradigm, 8 in the parahippocampal gyrus, characteristic of the spatial imagery paradigm. Globally, 24 % of the patients performed at least 1 of the 2 tasks, indicating a capacity to understand and carry out instructions, which suggests a preserved consciousness. The connectivity of the resting-state networks showed a correlation with the state of consciousness. CONCLUSIONS Absence of feedback, and involuntary movements, which in some cases required sedation, were the main difficulties encountered. Nonetheless,

Neuroradiology (2013) 55 (Suppl 1):S15–S159 clinically significant and sometimes unexpected results were observed in certain patients. fMRI is therefore a feasible and useful examination in patients with disorders of consciousness. Its results should, however, be assessed alongside those of other clinical examinations and imaging results. Keywords fMRI, consciousness, vegetative state, MCS CO.06.02 CHANGES OF GABA AND GLUTAMINE IN JUVENILE MYOCLONIC EPILEPSY MEASURED BY MR SPECTROSCOPY C. Lueckerath1, U. Pilatus1, S. Knake2, M. Kieslich3, E. Hattingen1 1

Neuroradiology, Goethe University Frankfurt, Frankfurt, Germany, Centrum of Epilepsy Hessen, Marburg, Germany, 3Pediatric Neurology, Goethe University Frankfurt, Frankfurt, Germany 2

PURPOSE In juvenile myoclonic epilepsy (JME) congenital alterations of GABAergic neurotransmission play an important role. Dysfunction of thalamocortical circuits is considered to trigger JME. This thalamocortical network is reciprocally connected by excitatory glutamatergic and inhibitory GABAergic projections. In addition, subtle frontal lobe dysfunction has been found in JME together with glucose hypometabolism and hypoperfusion. Positron emission tomography with 11C-labeled Flumazenil revealed particularly increased binding with the benzodiazepine/ GABA receptor complex in the cerebral frontal cortex of JME patients. Therefore we aimed to evaluate if concentration of GABA and of its counterpart glutamate is altered the target areas (thalamus, frontal lobe) as well as in the motor cortex. For this purpose MR spectroscopic GABA editing as the method for in vivo measurement of GABA was performed in different brain regions of JME patients and agematched controls. METHODS Thalamus, frontal lobe and motor cortex of the dominant hemisphere were measured at 3 T in 32 JME patients and 16 controls. Single voxel spectroscopy was performed using a GABA editing sequence (MEGAPRESS) and a short-TE PRESS (30 ms) sequence. Short-TE data were processed with LCModel allowing to discriminate between glutamine and glutamate. Concentrations of GABA, glutamate and glutamine, N-acetyl-aspartate (NAA), creatine and choline of the three target brain regions were compared between patients and controls. RESULTS In patients, GABA and NAA were significantly decreased in the thalamus. GABA and glutamine were significantly increased in the frontal lobe. CONCLUSION The increase of GABA in the frontal lobe of JME patients which already showed higher receptor affinity implicates a pathological up-regulation of GABA in this brain region explaining frontal dysfunction. Higher glutamine levels may implicate that glutamate regulation is also affected. Reduced GABA implicates GABAergic dysfunction maybe causing JME. The decrease in NAA reflects neuronal damage which also has been caused by GABAergic dysfunction. ααα11 Keywords Juvenile myoclonus epilepsy, GABA editing, MR spectroscopy CO.06.03 LIMBIC DYSCONNECTIVITY IN DISORDERS OF CONSCIOUSNESS C. Di Perri1, S. Bastianello2, A. Bartsch3, C. Pistarini4, G. Maggioni4, L. Magrassi5, R. Imberti5, A. Pichiecchio2, S. Laureys1, F. Di Salle6

S61 1

Coma Science Group, Liege, Belgium, 2Mondino, Pavia, Italy, University of Heidelberg, Heidelberg, Germany, 4Maugeri, Pavia, Italy, 5 S. Matteo, Pavia, Italy, 6 University of Salerno, Salerno, Italy 3

PURPOSES To investigate functional connectivity between the Default Mode Network and other networks in disorders of consciousness. METHODS We analyzed 11Vegetative State and 7 Minimally Conscious State patients with age- and gender- matched healthy controls. MRI data underwent a careful non-linear spatial normalization to compensate for disease-related anatomical distortions. Brain connectivity was analyzed in resting-state MRI temporal series by combining non-inferential (Independent Component Analysis) and inferential (Seed-Based General Linear Model) methods. RESULTS We show that concurrently with Default Mode Network hypoconnectivity, patients’ functional connectivity of the DMN is shifted to and paradoxically increased with limbic structures, including orbitofrontal cortex, insula, hypothalamus and the ventral tegmental area. CONCLUSIONS Concurrently with Default Mode Network hypoconnectivity, we report the evidence of limbic hyperconnectivity in Vegetative State and Minimally Conscious State patients. This hyperconnectivity may reflect the persistent engagement of residual neural activity in self-reinforcing neural loops which could subtract crucial neural resources from the plasticity of patients’ brains. Keywords Disorders of consciousness, functional connectivity, limbic system CO.06.04 O P T I C PAT H WAY I N V O LV E M E N T I N A L S T R O M SYNDROME: A MRI MULTIMODALITY STUDY V. Citton1, A. Favaro2, J. Marshall3, V. Bettini4, N.A. Greggio5, F. Favaretto 4 , G. Milan 4 , K. Naggert 3 , P. Meneguzzo 2 , G. Zorzi 2 , A. Salvalaggio2, C. Idotta2, L. Weis1, P. Maffei4, R. Manara1,6 1

Neuroradiology Unit, IRCCS San Camillo Hospital, Venice, Italy, Department of Neurosciences, University of Padua, Padua, Italy, 3The Jackson Laboratory, Bar Harbor, ME, USA, 4Internal Medicine 3, Dept. of Medicine, University Hospital of Padua, Padua, Italy, 5Pediatric Endocrinology Unit, Dept of Pediatrics, University Hospital of Padua, Padua, Italy, 6Neuroradiology Unit, University of Salerno, Salerno, Italy 2

BACKGROUND Alstrom syndrome (AS) is a genetically determined ciliopathy with primary progressive cone-rode dystrophy. Blindness occurs usually during adolescence. Aims: to investigate brain involvement along the optic pathways in AS by means of conventional and quantitative MRI. MATERIAL AND METHODS Eleven AS patients (mean-age 23 years; range: 6–45; 5 females) and 19 age- and gender-matched controls underwent brain MRI (Achieva 1.5 T, Philips). The MRI study protocol included 3D-T1, FLAIR, diffusion tensor imaging (32 directions; b-value=800 s/mm2) and resting state functional MRI (250 continuous functional volumes). Voxel based morphometry and cortical thickness analyses, independent component analysis and tract based spatial statistics were performed using dedicated softwares (Freesurfer, SPM8 and FSL). RESULTS Five AS patients were totally blind; 6 patients presented with severe low vision. AS patients showed significantly lower grey (5386 voxels, peak: 16, -68, 6) and white matter density in the occipital lobes, while cortical thickness did not differ from controls. The optic radiation disclosed significantly reduced fractional anisotropy (peaks: 33, -65, -2 and 28, -60, -1) and increased radial diffusivity (peaks: 31, -65, 11 and −25, -68, 0), while mean and axial diffusivity did not differ significantly. AS patients had reduced

S62 connectivity (2189 voxels; peak: 21, -51, -3) within primary visual area with sparing of the occipital pole. CONCLUSIONS Our multimodality MRI study on AS disclosed occipital atrophy encompassing both white and gray matter, optic radiation white matter derangement consistent with demyelination and profound primary visual area dysfunction. Beside secondary changes due to retinal dystrophy, primary myelin derangement and selective occipital neural reorganization might have a role in determining optic pathway MRI changes in AS. Keywords Alstrom syndrome, MRI, optic pathway CO.06.05 RESTING-STATE FMRI IN AN INTRAOPERATIVE MRSETTING: FEASIBILITY AND PRELIMINARY RESULTS S. Bisdas1, C. Roder2, E. Charyasz1, U. Klose1, M.S. Tatagiba2, U. Ernemann1 1 2

Eberhard Karls University, Neuroradiology, Tübingen, Germany, Eberhard Karls University, Neurosurgery, Tübingen, Germany

PURPOSE Resting-state functional MRI (fMRI) has emerged as an important method for assessing neural networks, enabling extensive connectivity analyses between multiple brain regions. This method might provide important results in an intraoperative setting of high-field intraoperative MR scanners. The aim of this study was to investigate the feasibility to perform restingstate fMRI during neurosurgical procedures in anesthetized patients. METHODS Twenty patients referred for a surgical resection of intracranial masses were included in this study after informed consent was obtained. All patients received total intravenous anesthesia with propofol 2 % and fentanyl. The subjects were continuously monitored and ventilated by specifically designed MR-compatible devices. A 1.5-T MR scanner placed in a operating room with an adapted operating table (IMRIS, Nuernberg, Germany) was used for resting-state fMRI. Three-dimensional anatomical T1- and T2-weighted images for co-registration were acquired prior to the EPI measurements (TR 2 s, TE 50 ms, resolution 3,4*3,4*3 mm3, 153 repetitions). Measurements were performed before surgical intervention. Single-subject independent component (IC) analysis was performed with the GIFT toolbox (MIALAB, Mind research Network) using previously described methods and algorithms. Smoothed data were decomposed into 41 components. The components were assigned to published resting-state network (RSN) components as far as possible. RESULTS In all patients, up to 12 from the 28 published RSN components could be identified, including auditory network (IC 17), sensorimotor networks (IC 07, 23, 24), default-mode networks (IC 25, 50, 53), attentional networks (IC 52, 55, 71, 72, 60) and visual networks (IC 46, 64, 67) . No reduction of the RSN intensity in comparison to subjects in resting wakefulness was found. CONCLUSIONS Our preliminary results show that resting-state fMRI measurements can be performed with anesthetized patients using intraoperative high-field MRI system. This opens new avenues for functional navigation allowing a real-time intraoperative identification of resting-state connectivity. Keywords fMRI, resting-State fMRI, intraoperative MRI CO.06.06 ASSESSMENT OF THIRD VENTRICULOSTOMY PATENCY W I T H 3 D - S PA C E T E C H N I Q U E : A M U LT I C E N T E R RESEARCH STUDY O. Algin1, M. Ucar2, M.G. Kartal1, A. Börcek2, P.A. Ozisik3, E. Ozmen1, T. Tali2

Neuroradiology (2013) 55 (Suppl 1):S15–S159 1 Ataturk Training and Research Hospital, Ankara, Turkey, 2Gazi University, Medical Faculty, Ankara, Turkey, 3Koru Hospital, Ankara, Turkey

INTRODUCTION Endoscopic third ventriculostomy (ETV) is being used in increasing frequency in the treatment of obstructive hydrocephalus. The aim of this study is to determine the efficacy of 3D-SPACE in evaluation of patients with ETV. MATERIALS AND METHODS 25 patients (mean age: 22 years; range: 4—74) treated with ETV between 2010 and 2013 were included in the study. MRI examinations performed in two different 3-tesla MRI scanners (Trio&Verio scanners, Siemens). Sagittal plane 3D-T1W, 3D-heavily-T2W, and 3D-SPACE with variant flip angle mode images were obtained with isotropic voxel sizes. Sagittal and axial planes PC-MRI images with retrospective cardiac gating were also obtained. For the evaluation of ETV patency, the following findings were evaluated using the 3D and flow analysis tools of the same dedicated workstations (Leonardo, Siemens): diameter of stoma and third ventricle, flow void sign on 3D-SPACE with variant FAM and PC-MRI images, third ventricular integrity on heavily-T2W images, and quantitative PC-MRI parameters of the stoma. Results of 3D-SPACE technique were statistically analyzed with the PC-MRI and clinical findings. RESULTS In 22 patients, the etiology of hydrocephalus was aqueductal stenosis; in 3 patients, the cause was fourth ventricular outlet obstruction (FVOO) or complex hydrocephalus. 3D-SPACE, PC-MRI, and clinical findings in 4 patients were consistent with closed stoma. In one patient PC-MRI findings were equivocal. On the other hand clinical examination and 3D-SPACE findings were consistent with patent stoma. In 3 patients findings were equivocal in heavily-T2W images. Evaluation of other sequences obtained and clinical examination revealed that in 2 of these 3 patients it was patent whereas in the last one it was closed. 3D-SPACE was the sequence that correlated best with PC-MRI and/or clinical findings (p<0.05). DISCUSSION 3D-SPACE seems to be the most efficient sequence used to determine patency of ETV. This new technique and our optimized protocol may prevent false positive or negative results of PC-MRI and heavily & thinsection T2W sequences. Also, 3D-SPACE provides accurate data in a reasonable time period in most of the patients with ETV. In patients with negative results on 3D-SPACE images, PC-MRI or other techniques (such as cisternography) may be unnecessary. Keywords Endoscopic third ventriculosto, 3D-SPACE, obstructive hydrocephalus CO.06.07 ROLE OF COMBINED STRUCTURAL MR IMAGING AND SPECT CT IN THE MANAGEMENT OF REFRACTORY EPILEPSY K. Rahmat, H. Taha, N. Ramli, F. Fadzli, K.S. Lim University of Malaya, Kuala Lumpur, Malaysia BACKGROUND AND PURPOSE Optimised epilepsy screening MRI protocol is highly sensitive and specific in the detection of anatomic substrates . Combined functional and MRI is essential for the diagnostic work up of medically refractory epilepsy patients to identify suitable candidates for surgery . The purpose of this study was to investigate the collaborative role of MRI, SPECT CT and EEG in the work up of epilepsy patients. We aimed to evaluate the concordance of functional SPECT CT to clinical lateralization by EEG and structural imaging by MRI and to assess the timing of ictal SPECT for seizure localization versus propagation seizures.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS Patients with refractory focal epilepsy who had been scheduled for video-EEG telemetry and SPECT (99 m Tc-HMPAO) were recruited. Anti-epileptic drugs were withdrawn in all cases. MRI was performed on the 3 Tesla scanner with epilepsy protocol. Ictal or interictal SPECT CT was performed following injection of radiotracer 99 m T-HMPAO. SPECT CT images were co-registered with 3 D FSPGR (fast spoiled gradient-echo) sequence with multiplanar reformats. Correlation with histopathology of surgical specimens was performed when available. RESULTS A total of 18 subjects had EEG and MRI, of which 7 underwent ictal and 11 interictal SPECT CT. MRI findings included mesial temporal sclerosis, cortical malformations , arachnoid cyst and normal scan.Ictal SPECT scans delineated the epileptogenic zone and seizures propagation as areas of cerebral hyperperfusion. Seizures foci showed areas of hypoperfusion in the interictal scan.The success rate in acquiring ictal SPECT increased from 25 % (2 out of 8) to 50 % (5 out of 10) after the final protocol was established .The concordance rate between ictal SPECT and MRI/EEG was higher than interictal SPECT and MRI/EEG. All ictal SPECT were concordant with the EEG localization. CONCLUSION Combination of Ictal SPECT CT , MRI and ictal EEG provides complementary information in presurgical evaluation of refractory epilepsy patients.SPECT CT is particularly useful in patients with normal MRI findings, abnormal MRI findings with incongruent EEG and nonlocalizing EEG. Keywords Epilepsy, SPECT, MRI CO.06.08 CAPABILITIES OF MRI IN ASSESSMENT OF RESULTS OF FOCAL CRYOABLATION OF THE MAMMALIAN BRAIN (EXPERIMENTAL WORK) S. Osipov, V.V. Khovrin, T.N. Galyan, S.A. Vasiliev, S.B. Pesnya-Prosolov Petrovsky National Research Center of Surgery, Moscow, Russia INTRODUCTION Surgical management of brain tumors is based on choice of surgical approaches, tactics and removal technique, radicalism of tumor excision, preservation of functionally important brain structures. Therefore cryosurgery is a perspective method in treatment of brain tumors. Purpose: To evaluate the MRI facilities in assessment the results of local cryoablation of the mammalian brain. Methods and materials: The research included 26 experiments performed on 13 pigs and 13 rabbits. In vivo brain MRI was performed on Hitachi APERTO 0,4 T tomograph using T1-WI, T2-WI and Flair, strictly on 1st, 2nd, 3rd, 7th, 14th, 21st, 28th day after cryotherapy procedure. These data were compared with the results of morphological examination. RESULTS In early postoperative period in the area of cryotherapy a hyperintensive signal on T2-WI and FLAIR and slightly hypointensive signal on T1WI had been received. The area of cryoablation was round-shaped with rather sharp and smooth margins. This was interpreted as the area of local edema-ischemia in the region of cryotherapy. During follow-up in above-mentioned days the intensity of MR-signal in cryoablation area changed and formation of cystiform structures with the signal close to that from the CSF were registered. Postoperative cyst formation was observed on the 14th day after cryotherapy. Morphologically on the first day the post-cryotherapy area was presented as a zone of destruction of brain tissue with hemorrhages along the small vessels. On MRI it corresponded to the signs of edema

S63 and ischemia. In intact brain tissue the pericellular and perivascular edema was not clearly differentiated from the area of cryoablation by MRI. From the 2 day an appearance of a distinguishable border between the mentioned zone and perifocal edema was noted. On MRI it corresponded to the formation of leukocytic demarcation, which increased to the 3 day and gradually decreased to the end of second week. In morphology the size of necrotic changes in area of cryoablation is corresponded to those by MRI. CONCLUSIONS MRI is helpful in assessment of cryodestruction results, allows to differentiate the cryonecrotic zone, perifocal edema and normal brain tissue. Keywords Cryodestruction, MRI, animals MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 5 17:00–18:30 PARALLEL SCIENTIFIC SESSION - FREE TOPICS CO.07.01 MR FINDINGS AND IMAGING TYPES OF FOCAL CORTICAL DYSPLASIA M. Zhu, D. Zhao, T. Du, L. Wang, X. Zhang, X. Chen Dept. of Neuroradiology, Beijing Sanbo Brain Hospital, Beijing, China PURPOSE Focal Cortical Dysplasia (FCD) is a localized form cerebral cortex malformation. It usually associates with intractable epilepsy in both children and adults. A broad clinicopathologic spectrum of FCD has been described. The imaging appearances and pathologic classification of FCD have been reported not correlated very well. The MR finds of FCD were varied in literature. In this study, we tried to analyze the MRI findings of FCD and then to summary imaging types of FCD. METHODS MR images of 54 patients with pathologic confirmed FCD were included. The patients with second lesion in imaging or pathologic study were excluded. Axial T1,T2,and FLAIR image with 5 mm slice thickness, coronal T2 and FLAIR imaging with 3 mm thickness, and a sagittal 5 mm thickness FLAIR images were obtained on a 1.5 T MRI scanner. Lesion location ,cortex thickness, the gray/white matter junction, subcortical white matter signal intensity, and morphology of gyri and sulci of patient with FCD were evaluated retrospectively. RESULTS Focal cortical and subcortical hyperintensity were found in 51 patients. The thickening of focal cortex was found in 42 cases, blurring of gray/white matter junction in 46 patients, the malformation of gyri or sulci in 31 cases. Based on MRI findings of FCD, the imaging appearances of FCD were classified into 3 types: Radial band, hyperintense, and mild type FCD . Radial band FCD showed a white matter hyperintense tapering toward the wall of lateral ventricle. Ten cases showed radial band FCD in our group. Hyperintense FCD displayed a subcortical white matter hyperintense without tapering sign. There are 25 hyperintense FCD. Mild FCD showed focal cortical thichness or a slightly focal cortical hyperintense without underlying whitematter signal changes. The mild type of FCD was classified in 19 patients in our patient group. CONCLUSION MR appearances of FCD could be classified into 3 types: radial band, hyperintensity and mild FCD. Understanding the MR imaging type of MR of FCD might improve the MR diagnosis of FCD. Keywords Focal cortical dysplasia, MRI, epilepsy

S64 CO.07.02 EXTRA CRANIAL VENOUS ABNORMALITIES IN PATIENTS WITH MULTIPLE SCLEROSIS (MS): A TRUE PATHOLOGICAL FINDING OR AN ANATOMICAL VARIANT? C. Torres1, M. Hogan1, C. Lum1, S. Chakraborty1, S. Patro1, H. Dabirzadeh1, T. Nguyen1, M. Bussiere2, M. Freedman1, R. Thornhill1, L. Kingstone1, S. Belanger1, B.A. Schwarz1 The Ottawa Hospital, University of Ottawa, Ottawa, Canada, 2Grey Nuns Community Hospital, Edmonton, Canada 1

PURPOSE To evaluate the extra cranial venous anatomy with contrast enhanced MR Venogram (CE-MRV) in patients without MS. To assess the prevalence of various venous anomalies such as asymmetry and stenosis in this population. METHODS & MATERIALS The study was approved by our local Research Ethics Board and all participants gave informed consent. We recruited 100 patients without MS referred for a contrast enhanced MRI, who underwent additional CEMRV from the skull base to the mediastinum on a 3 T scanner. The study started in February 2012 and was completed in July 2012. We included patients between 18 and 60 years old with a male: female ratio of 1:1. Exclusion criteria included prior neck radiation, neck surgery, neck or mediastinal masses or significant cardiac or pulmonary disease. Two neuroradiologists independently evaluated the studies to document the presence of asymmetry and stenosis in the jugular, vertebral and azygous veins. RESULTS Asymmetry of the IJVs was found in 75 % of patients. 85 % of patients had a focal stenosis in the right IJVand 82 % in the left IJV. The stenoses were found in the upper third of the vein in 95 % of the cases. Stenosis of the azygous vein was found in 10 % of patients. There was prominence of the external jugular veins in 39 % of cases, of the anterior jugular veins in 27 % and of the deep cervical veins in 22.4 %. CONCLUSION The venous anatomy of non MS patients demonstrates multiple variants including asymmetry and stenoses of the IJVs. We believe the stenoses in the upper third of the IJVs are secondary to indentation of the vessel between the posterior belly of the digastric muscle and the occipital bone. This study has been used as normative data to compare with CEMRV in the MS population (phase 2 of our study). Keywords Extra cranial venous stenosis, contrast enhanced MR Venogram CO.07.03 NSSAFE STUDY: OBSERVATIONAL STUDY ON THE INCIDENCE OF NEPHROGENIC SYSTEMIC FIBROSIS IN RENAL IMPAIRED PATIENTS FOLLOWING GADOTERIC ACID ADMINISTRATION B. Kress, A. Gottschalk Institute of Diagnostic and Interventional Neuroradiology, Krankenhaus Nordwest, Frankfurt, Germany PURPOSE To prospectively estimate the incidence of NSF in patients with moderate to severe renal impairment after administration of gadoteric acid. METHODS An ongoing worldwide post-marketing study (PMS) is conducted to collect safety data in 1,000 patients (adults and children) with moderate to severe and end stage renal impairment, scheduled to undergo a routine contrast-enhanced magnetic resonance (MR) imaging using gadoteric acid (Dotarem®). For each patient, risk factors at inclusion, indications for MR imaging, and occurrence of adverse events are recorded. Three follow up visits (between 3 months and 27 months after MRI) are performed in order to detect any suspicion or occurrence of NSF.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS As of January 18, 2013, the cut-off date for the interim safety analysis, this ongoing PMS included data on 232 patients (mean age: 70.2 years (range: 21–92); male: 62.5 %). The mean eGFR was 36.5 ±16.1 ml/min/1.73 m2 (range: 4.0-59.1) including 64.2 % of moderate, 18.5 % of severe, 14.2 % of end stage renal insufficiency and 2.6 % of kidney transplanted patients. CNS MR examinations accounted for nearly 25 %. The first follow-up visit was done for 67 patients (29 %) and no NSF occurred. Only 1 patient (0.4 %) had two serious adverse events not related to gadoteric acid. CONCLUSION This interim safety analysis already confirms the very good safety profile of gadoteric acid in renal impaired patients. Keywords Contrast agent, NSF, safety CO.07.04 A COMBINED LONG TERM MRI AND BEHAVIORAL STUDY ON STATUS-EPILEPTICUS INDUCED NEURODEGENERATION IN RAT: NEUROPROTECTION AND ALLEVIATED EPILEPSY-ASSOCIATED CO-MORBIDITIES BY ADD-ON TREATMENT WITH PHENOBARBITAL X. Ding1, J.P. Bankstahl2, M. Meier3,4, M. Bankstahl5, X. Tang1, H.J. Hedrich3, W. Löscher5, H. Lanfermann1 1 Institute of Diagnostic and Interventional Neuroradiology, Hannover Medical School, Hannover, Germany, 2Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany, 3REBIRTH Unit 8.4, Hannover Medical School, Hannover, Germany, 4Institute of Laboratory Animal Science, Hannover Medical School, Hannover, Germany, 5 Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany

PURPOSE Status epilepticus (SE) is a common insult that may lead to development of temporal lobe epilepsy (TLE) characterized by hippocampal neurodegeneration. In addition, neurodegeneration in TLE is associated with psychological and cognitive dysfunctions and pharmacoresistance. Neuroprotective treatment during or shortly after SE could be an option to reduce psychological co-morbidities and improve treatment of possibly followed chronic epilepsy. This study aims to estimate treatmentmediated reduction of neurodegeneration and behavioral dysfunction by long term MRI follow-ups combined with a behavioral test battery. METHODS A fractionated rat pilocarpine model that mimics clinical and neuropathological features of TLE was used. SE was interrupted either with a combination of diazepam (DZP) and phenobarbital (PB, n=7) or with DZP alone (n=7). Six additional rats were taken as controls. MR scans were performed before, and 24 h, 48 h, 1 week, 6 weeks, 3 months, and 6 months after SE onset to include acute, latent and chronic phases of epileptogenesis. All MR examinations were conducted on a 7 Tesla animal scanner (Pharmascan 70/16, Bruker, Ettlingen). The time-dependent volume changes of hippocampus, CSF space and whole brain volume were manually measured. Six months after SE, all animals performed a behavioral testing battery consisting of tests for learning and memory, explorative and anxietyassociated behavior, and hyper-excitability. Results: Spontaneous seizures occurred in all animals exhibiting SE. Increasing cellular edema occurred immediately after SE, with a maximum at 24 h to 48 h post SE. Subsequently, edema disappeared while continued degeneration of the tissue became obvious with loss of volume of the whole brain and the hippocampus. All rats showed similar time dependency concerning volume reduction. However, the group treated only with DZP exhibited more severe volume loss than the PB-treated group, especially during the period of 1 to 6 weeks after SE. In the behavioral test battery PB-treated rats showed significantly better performance in a learning and memory test (Morris Water Maze), but

Neuroradiology (2013) 55 (Suppl 1):S15–S159 exhibited no major differences in explorative and anxiety-associated behavior or hyper-excitability. In conclusion, SE-induced neurodegeneration is a long lasting process associated with behavioral changes that can be reduced by add-on treatment with PB. Keywords Temporal lobe epilepsy, 7 T MRI, add-on treatment CO.07.05 THE RELATIONSHIP BETWEEN HOUNSFIELD UNIT VALUES OBTAINED FROM SKULL BASE CT IMAGES AND DEXA FINDINGS M. Varer, M. Gursoy, M. Apaydin, E. Uluç, O. Oyar Department of Radiology, Katip Celebi University Ataturk Education and Training, Izmir, Turkey BACKGROUND Head computed tomography (CT) imaging is a frequently used modality for the evaluation of patients for many reasons such as headache, syncope, trauma, serebrovascular disease. During a long period of head CT evaluation considerable variations of skull base bone density was striking.The purpose of this study was to determine if Hounsfield unit (HU) values , a standardized CT attenuation coefficient, obtained from skull base CT images correlate with bone mineral density . METHODS Ninety-four patients( including 11 male and 83 female patients with a mean age of 59.97 years) undergoing both cranial CT imaging and dual x-ray absorptiometry (DEXA) scans were evaluated. For all patients 3 different skull base-clivus HU values for an area of 30 mm2 were obtained . Then the mean value of the three measurements was calculated. These mean values were then correlated with the T scores of the lumbar spine, femur neck and Wards area . RESULTS Significant correlations were found between skull base HU values and DEXA T score values for femur neck, lumbar spine( L1-4) and Wards area (p<0,05).According to ROC analysis , for skull base HU values below 140, the sensitivity was found to be 80 % and specificity 70.4 % for predicting osteoporosis . CONCLUSION Statistically significant correlation was found between the HU values of skull base and DEXA T score values . It was concluded that for skull base HU values below 140 osteoporosis and consequently fracture risk could be predicted and DEXA evaluation could be suggested. Keywords CT, osteoporosis, skull base CO.07.06 EFFICACY AND RELIABILITY ANALYSIS OF 3D-SPACE SEQUENCE IN THE EVALUATION OF PATIENTS WITH HYDROCEPHALUS G. Kartal1, M. S. Ugurel2, O. Algin1 1 Ataturk Training and Research Hospital, Ankara, Turkey, 2Gulhane Military Medical Academy, Ankara, Turkey

INTRODUCTION Three-dimensional sampling perfection with application optimized contrasts using different flip angle evolutions (3D-SPACE) is a useful technique in evaluation of hydrocephalus. However, inter- and intraobserver variability of this sequence is not yet determined. In this retrospective study, we aimed to investigate the effectiveness and additive value of 3D-SPACE with variant flip-angle mode in imaging of all types of hydrocephalus. Our secondary objective was to assess the

S65 reliability of 3D-SPACE sequence and correspondence of the results with phase-contrast cine MRI (PC-MRI) based data. METHODS 41 patients with diagnosis or suspicions of hydrocephalus have undergone 3 T MRI. 3D-SPACE sequence has been obtained in addition to routine hydrocephalus protocol. Cerebrospinal fluid circulation, presence/type/etiology of hydrocephalus, obstruction level scores, and confidence levels were evaluated separately by two radiologists. In the first session, routine sequences with PC-MRI were evaluated, and in another session, only 3D-SPACE and three-dimensional magnetization prepared rapid-acquisition gradient-echo (3D-MPRAGE) sequences were evaluated. Results obtained in these sessions were compared with those obtained in consensus session. RESULTS Agreement values were very good for both 3D-SPACE and PC-MRI sequences (p<0.001 for all). Also, the correlation of more experienced reader’s 3D-SPACE-based scores and consensus-based scores was perfect (kappa value=1, p<0.001).The mean value of PC-MRI-based confidence scores were lower than those obtained in 3D-SPACE and consensus sessions. CONCLUSIONS 3D-SPACE sequence provides morphologic and physiologic data. It is a non-invasive technique providing extensive multiplanar reformatted images in an acceptable acquisition time and with a lower specificabsorption rate. These advantages over PC-MRI make 3D-SPACE sequence a promising tool in management of patients with hydrocephalus. Keywords CSF, hydrocephalus, MRI CO.07.07 NOVEL DEVICE AND PROCEDURE FOR THE TREATMENT OF EPIPHORA H. Maan1, C. Oliver2, B. Willoughby3, J. Steele4, D. Schomer1 Banner MD Anderson Cancer Center, Gilbert, AZ, USA, 2Colorado Head and Neck Specialists, Denver, CO, USA, 3University of Colorado School of Medicine, Denver, CO, USA, 4MD Anderson Cancer Center, Houston, TX, USA 1

PURPOSE Epiphora treated by Jones tube placement is an accepted practice that has seen little innovation since its introduction in the 1960's. Jones tube predilection for migration, poor patient tolerance and cosmesis has led to the development of the modern Dacro Cysto Sinusotomy (DCS) stent as a novel alternative therapy for epiphora. A pilot study was performed to evaluate the DCS device and procedure. METHODS 19 patients received lacrimal sinus diversion utilizing the DCS stent developed by Sinopsys Surgical for the treatment of epiphora. The DCS stent is placed posterior to the lacrimal caruncle within the medial angle of eye with distal terminis in the anterior ethmoid air cell. RESULTS With adequate anchoring, all patients experienced 80 % or greater relief of symptoms. All patients requested to have the DCS stents left in place after termination of the study for continued symptom relief. The most common adverse event was temporary conjunctivitis, itching/burning and foreign body sensation. CONCLUSION The modern DCS stent is a safe and effective alternative to Jones tube placement that allows better cosmesis and is less prone to migration with improved epiphora symptom relief. However, larger scale studies will need to be undertaken to validate these initial findings.

S66 CO.07.08 NOVEL APPLICATION OFA NEW EPIPHORATHERAPY TO TREAT RHINOSINUSITIS H. Maan1, C. Olivier2, B. Willoughby3, J. Steele4, D. Schomer1 Banner MD Anderson Cancer Center, Gilbert, AZ, USA, 2Colorado Head and Neck Specialists, Denver, CO, USA, 3University of Colorado School of Medicine, Denver, CO, USA, 4MD Anderson Cancer Center, Houston, TX, USA 1

PURPOSE Rhinosinusitis affects 35 million people annually and is listed as one of the top 5 reasons for missed work. Lacrimal Sinus Diversion utilizing a Dacro Cysto Sinusotomy (DCS) stent is a novel innovation that allows direct sinus irrigation and delivery of a plethora of ophthalmologic medications directly into the ethmoid sinuses. METHODS 17 patients with sinonasal symptoms were evaluated with the SinoNasal Outcomes Test (SNOT-20) questionnaire and routine Sinus CT. Each patient then received lacrimal sinus diversion utilizing a DCS stent, developed by Sinopsys Surgical. All patients were placed on daily eye drops of steroids and antibiotics for 2 weeks, allergy eye drops X 30 days+and then reevaluated at 3 weeks with repeat SNOT-20 questionnaire and sinus CT. RESULTS 34 stents were placed in a total of 17 patients with one gross procedure deviation but without long-term complication. With adequate anchoring, SNOT-20 scores were reduced greater than 66 % in all patients and greater than 80 % in half of the patients. The most common adverse event was temporary conjunctivitis, itching/burning and foreign body sensation. CONCLUSION Lacrimal sinus diversion utilizing the Sinopsys Surgical DCS stent demonstrates tremendous promise in relieving the symptoms of rhinosinusitis by allowing irrigation and targeted medication therapy to the ethmoid sinuses. Preliminary studies demonstrate significant improvement of symptoms and mucosal inflammation with impressive safety profile at a nominal cost. CO.07.09 DRUG-RESISTANT TEMPORAL LOBE EPILEPSY: ROLE OF MAGNETIC RESONANCE IN THE STUDY OF FOCAL CORTICAL DYSPLASIA ASSOCIATED WITH LOW-GRADE TUMOR F. Toni1, A.F. Marliani1, F. Bartiromo1, A. Tarsi1, G. Marucci2, M. Martinoni3, L. Volpi4, P. Riguzzi4, G. Rubboli4, R. Michelucci4, M. Giulioni3 1 IRCCS Istituto delle Scienze Neurologiche di Bologna, Neuroradiology Department, Bellaria Hospital, Bologna, Italy, 2IRCCS Istituto delle Scienze Neurologiche di Bologna, Department of Pathology, Bellaria Hospital, Bologna, Italy, 3IRCCS Istituto delle Scienze Neurologiche di Bologna, Division of Neurosurgery, Bellaria Hospital, Bologna, Italy, 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy

PURPOSE Magnetic resonance imaging (MRI) is mandatory to identify the epileptogenic zone in drug-resistant temporal lobe epilepsy (DR-TLE). Low grade tumour (LGT) and focal cortical dysplasia (FCD) are common findings in symptomatic DR-TLE, and frequently coexist. The correct identification of the lesions is essential to obtain positive post-operative seizure outcome. This study aims to identify the role of MRI in the diagnosis of FCD associated with temporal lobe LGT.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS We retrospectively reviewed MRI scan performed on a high-field system of twenty-four patients with DR-TLE associated with LGTs, who were surgically treated for intractable epilepsy. Fourteen of them had histologically proven FCD. Pre-operative MR exams were reviewed by two experienced neuroradiologists involved in the epilepsy programme and subsequently compared with histological data. RESULTS In the diagnosis of FCD MRI demonstrated a 64–86 % sensitivity and 27-36 % specificity. An incomplete imaging protocol, the big dimensions of the tumor, the infiltration and the related oedema were the most important factors limiting MRI accuracy. CONCLUSIONS Despite the acquisition of adequate study protocol equipped with high field MR system and the neuroradiologist experience MRI diagnosis of FCD dysplasia associated with low grade tumor of the temporal lobe is still challenging. Keywords Focal cortical dysplasia, temporal lobe epilepsy, low-grade tumor MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 3 17:00–18:30 PARALLEL SCIENTIFIC SESSION - STROKE RECANALIZATION CO.08.01 MULTIMODAL APPROACH IN THE INTRA-ARTERIAL TREATMENT OF ACUTE ISCHEMIC STROKE E. Puglielli1, M. Varrassi1, M. Fuschi1, V. Di Egidio2 1

Interventional and Vascular Radiology, G. Mazzini Hospital, Teramo, Italy, General and Interventional Radiology, S. Spirito Hospital, Pescara, Italy

2

PURPOSE Recanalization has been identified as a major prognostic factor for good outcome in acute ischemic stroke (AIS). The purpose of this study was to evaluate technical feasibility, safety, and efficacy of multimodal and mechanical thrombectomy in the treatment of AIS. METHODS 78 consecutive patients with AIS (mean age 58,7y, from April 2009 to March 2013), with on-set less than 6 hours for the anterior circulation and 12 for the verbtebrobasilar one, undergoing to the endovascular therapy using retrievable stents or multimodal treatment approaches including, thromboaspiration, intravenous and/or intra-arterial thrombolysis, pharmacologic and PTA/permanent stent placement. MRI or CT/CT-Perfusion and Digital Subtraction Angiograpy were used for the imaging. Clinical outcome and mortality were assessed after treatment. Patient’s age, sex, etiology of occlusion, symptom, median NIHSS score at presentation and modified Rankin Scale (mRS), recanalization rates evaluated with TICI (Thrombolysis in Cerebral Ischemia: grade 0 (no flow) grade 3 (normal flow), and hemorrhagic complications were recorded and correlated using a multiple logistic regression analysis. RESULTS Median NIHSS score at presentation was 21 (range 5–36). Sites of arterial occlusion before treatment were: M1 35/78 patients (44.87 %), intracranial carotid 7/78 patients (8.97 %), M2 12/78 (15.38 %), tandem occlusion 6/78 (7.69 %), extracranial internal carotid isolated occlusion 5/78 (6.41 %), P1 7/78 (8.97 %), basilar trunk 6/78 (7.69 %). Therapeutic interventions: multimodal therapy 23/78 patients (29.48 %), pharmacologic cheap with tissue plasminogen activator (t-PA) 11/78 patients (14.10 %), mechanical embolectomy 44/78 (56.41 %). Successful recanalization (TICI 3 or 2b) was achieved in all patients (TICI III in 61/78 [78.02 %]), with high rate of recanalization for mechanical thrombectomy (TICI III in 42/44 [95.45 %]), compared to pharmacologic therapy only (TICI III 6/11 [54.54 %]) or multimodal therapy (TICI III 18/23 [78.26 %]), p<0.001. Asymptomatic

Neuroradiology (2013) 55 (Suppl 1):S15–S159 hemorrhagic sufusion occurred in one patient with M1 occlusion that spontaneously resolved. At 6 months, good functional outcome (mRS 0–2) was observed in 42.30 % (33/78); procedural mortality was 5.12 % (4/78). CONCLUSION Rate and stability of recanalization can predict the neurologic outcome. A multimodal endovascular approach using also the retrievable stents in AIS has high recanalization rates, with very low complications. Keywords Stroke, interventional, recanalization CO.08.02 SUBARACHNOID HAEMORRHAGE AFTER MECHANICAL INTRA-ARTERIAL THROMBECTOMY IN ACUTE ISCHEMIC STROKE: IMAGING FINDINGS AND CLINICAL SIGNIFICANCE O. Nikoubashman1, M. Gindullis2, K. Frohnhofen1, R. Pjontek1, M. Brockmann1, A. Reich2, J. Schulz2, M. Wiesmann1 1

Klinik für Diagnostische und Interventionelle Neuroradiologie, Uniklinik Aachen, Aachen, Germany, 2Klinik für Neurologie, Uniklinik Aachen, Aachen, Germany PURPOSE Investigation of the clinical significance of postinterventional subarachnoid haemorrhage (SAH) after endovascular mechanical thrombectomy in acute ischemic stroke. METHODS Data of 108 consecutive patients who received postinterventional CT scans within 4.5 h after mechanical thrombectomy were analysed retrospectively. RESULTS SAH was present in 23 of 108 patients (21.3 %). A perforation was observed during intervention in only 6 of 23 cases (26.1 %). There was haemorrhagic transformation in 4 of 23 patients with SAH (17.4 %): 2 patients suffered from an ECASS-PH1 bleeding and 2 patients suffered from an ECASS-PH2 bleeding.Both of the latter occurred in patients with apparrent intrainterventional perforations. There was a correlation between the occurrence of postinterventional SAH and the number of interventional thrombus extraction attempts (p=0.008, Chi2 test). Furthermore, the correlation betweeen postinterventional SAH and the occurrence of parenchymal haemorrhage was significant in our series (p=0.018, Chi2 test). CONCLUSION Postinterventional SAH after endovascular mechanical thrombectomy in acute ischemic stroke are likely to occur in complicated cases in which more than one revascularisation attempt is performed. Furthermore, postinterventional SAH seems to be associated with parenchymal haemorrhage. Keywords Stroke, subarachnoid haemorrhage, neurointervention CO.08.03 IMPORTANCE OF PRE-TREATMENT NEUROIMAGING IN IDENTIFYING ACUTE STROKE PATIENTS WITH LARGE INFARCTS WHO ARE UNLIKELY TO RESPOND TO IA THERAPY D. Frei1, A. Yoo2, D. Heck3, F. Hellinger Li4, V. Mccollum5, D. Fiorella6, A.S. Turk Lii7, T. Malisch8, O. Zaidat9, Z. Chaudry2, R. Gonzalez2, L. Barraza10, S.P. Sit10, A. Bose10 1 Swedish Medical Center, Englewood, CO, USA, 2Massachusetts General Hospital, Boston, MA, USA, 3Forsyth Medical Center, Winston-Salem, NC, USA 4Florida Hospital, Orlando, Fl, USA, 5Mercy Health Center, Oklahoma City, OK, USA, 6Stony Brook Medical Center, Stony Brook, NY, USA, 7Medical University of South Carolina, Charleston, SC, USA, 8 Alexian Brothers Medical Center, Elk Grove Village, IL, USA, 9Medical College of Wisconsin, Milwaukee, WI, USA 10Penumbra, Inc., Alameda, CA, USA

S67 PURPOSE The Penumbra START Trial is a multicenter, prospective trial with a goal of testing whether core infarct size on pre-treatment neuroimaging predicts clinical response to IA stroke therapy. METHODS Major inclusion criteria include presence of proximal artery occlusion of the anterior circulation, baseline NIHSS score 10 or greater, evaluable pretreatment imaging (NCCT, CTA source imaging, CT perfusion or MRI DWI) and treatment with the Penumbra System within 8 hours. Core infarct size was determined by a blinded imaging Core Lab. As prespecified, infarcts were trichotomized into small [ASPECTS 8–10 (NCCT, CTA-SI) or lesion volume <50 cc (CTP or DWI)], medium (ASPECTS 5–7 or volume 50–100 cc) or large (ASPECTS 0–4 or volume >100 cc). To date, 147 patients are enrolled at 27 centers, including 105 patients with Core Lab review and 90-day evaluation. Good clinical outcome is defined by 90day mRS 0–2. Review is still ongoing; statistical analysis is from the 105 patients with complete information. RESULTS Mean age is 66. Median NIHSS score is 19. Overall rate of TIMI 2–3 revascularization is 85 %. Forty-nine patients had a good outcome (47 %); 28 died (27 %). The number of evaluable scans for each modality is: 32 CTP, 83 CTA-SI, 80 NCCT and 6 DWI. In aggregate analysis pooling all modalities, there is a statistically significant relationship between core infarct size and good outcome, in that worse outcomes were seen only in the large infarct group. The good outcome rate is 55 % in small, 56 % in medium and 22 % in large infarcts (p=0.0019), despite similar recanalization rates (79 % small, 93 % medium, 84 % large). Independent predictors of good outcome were age, NIHSS score, time from onset to recanalization and infarct volume. CONCLUSION Pre-treatment neuroimaging is essential for identifying patients with large infarcts who are unlikely to respond to IA therapy. These results support the use of strict imaging criteria in patient selection. Keywords Stroke thrombectomy, neuroimaging, patient selection CO.08.04 LONG TERM O UTCOME AFTER INTRACRANIAL ANGIOPLASTY AND STENTING FOR ATHEROSCLEROTIC DISEASE W. Kuker, U. Schulz, D. Briley, P. Rothwell Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom PURPOSE Since 2006 we have performed angioplasty and stenting in patients with symptomatic intracranial atherosclerosis. Long term results are scarce for the efficacy of the procedure to prevent ischemic events. From 2010 all eligible patients were randomised for participation in the VIST trail. Patients treated with intracranial angioplasty or stenting before or outside the trial are presented here. PATIENTS 37 patients presented with symptomatic posterior circulation stenoses (32 vertebral, 5 basilar artery). 14 patients were treated with angioplasty alone, 10 with balloon mounted bare metal stents, 14 with drug eluting stents and 6 underwent angioplasty and stenting. Access failed twice. Primary endpoint was death or disabling stroke distal to the treated stenosis. 34 patients were available to long term follow up (6 to 50 months). All patients were reviewed clinically and had either DSA (n=12), MRA or CTA. RESULTS Procedural complications with permanent neurological deficits were encountered twice (basilar artery rupture and embolic stroke). Three

S68 patients fully recovered from procedural events and one patient encountered an asymptomatic vertebral artery occlusion. Two patients required urgent angioplasty of partially deployed stents. Three patients suffered further ischemic events during follow up and two died of other causes. No patient has suffered a disabling stroke downstream a treated stenosis. No further procedures were performed as the stents in symptomatic patients were either occluded (n=2) or not stenosed (n=1). Follow up imaging showed symptomatic stent occlusion in two patients and asymptomatic stent occlusion in one. One patient developed an asymptomatic pseudo-aneurysm after angioplasty. Follow up DSA showed partial re-stenoses after angioplasty or placement of bare metal stents but no restenosis of drug eluting stents. In patients with MRA follow up the restenosis grades could not be assessed due to stent artefacts. CONCLUSION Recurrent ischaemic events seem uncommon after successful angioplasty or stenting of an underlying posterior circulation stenoses. However further evidence is required comparing best medical treatment with endovascular intervention. Hence patients should be offered participation in an ongoing prospective randomised trial (VIST). Keywords Intracranial atherosclerosis, intracranial stenting, stroke prevention CO.08.05 E N D O VA S C U L A R T R E A T M E N T I N “ B E N I N G ” INTRACRANIAL HYPERTENSION. CLINICAL RESULT AND LONG-TERM FOLLOW-UP M. Aguilar Pérez1, K. Kurre1, S. Fischer1, D. Horward-Rizea1, R. Unsöld2, H. Bäzner3, H. Henkes1 1

Klinikum Stuttgart, Department of Neuroradiology, Stuttgart, Germany, Privatpraxis für Augenheilkunde, Düsseldorf, Germany 3Klinikum Stuttgart, Department of Neurology, Stuttgart, Germany 2

PURPOSE Idiopathic intracranial hypertension (IIH) is a disorder of increased intracranial pressure in the absence of any known causative factor, previously referred to as pseudotumor cerebri or benign intracranial hypertension. Although the severity of the symptoms can affect the activities of daily living, the most important factor to plan the treatment is the amount and progression of the visual loss. Recently stenting of stenotic dural sinuses has gained popularity as treatment of IIH since these stenoses may contribute to an obstruction of the venous return and hence CSF outflow. We prospectively evaluated the safety and efficacy of endovascular treatment in these patients. MATERIALS & METHODS A total of 29 patients underwent endovascular treatment of IIH. Most of them were women (76 %) and clinically obese. The mean age was 38.76 years. All the patients referred headache as clinical manifestation and the majority of them also any type of visual problems with all the patients presenting papilledema. Elevated intracranial pressure was documented in all the patients with an opening pressure >20 cm H2O. Magnetic resonance imaging was performed in order to exclude another cause of intracranial hypertension. Hyperintensity of the optic nerve sheath was observed in 90 % and an empty sella syndrome was present in 76 % of the patients. All the patients presented venous stenosis, 5 of them (17 %), unilateral and 24 (83 %), bilateral. Patients were treated with angioplasty and stenting of the venous stenosis if symptoms persisted under medical treatment, repeated lumbar punctures, CSF diversion procedures or a combination of them. Stent was placed in all 29 patients, in 11 (38 %) unilaterally and in 18 (62 %) bilaterally.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULT Resolution of the venous stenosis was possible in all the patients. There were no periprocedural or long-term complications. Improvement of papilledema was observed in all the patients and 90 % reported improvement of the headache after the treatment. In the mid-term followup (median 18 months, cumulative 404 months) only 5 patients (17 %) presented re-stenosis, which were retreated. CONCLUSION Endovascular treatment with sinus stenting is an easy, safe and effective treatment in patients with IIH. The far majority of patients have a persistent clinical benefit. Keywords Intracranial hypertension, pseudotumor, venous stenting CO.08.06 SIMPLE AND EASY WAY USING TIME-INTENSITY CURVE OF PERFUSION-WEIGHTED IMAGES TO FIND SALVAGEABLE PENUMBRA IN STROKE PATIENTS WITHIN 3.5 HOURS OF THE ONSET DUE TO THE CAROTID AND MIDDLE CEREBRAL ARTERY OCCLUSION T. Mori, T. Iwata, Y. Miyazaki, S. Kasakura, Y. Tanno, K. Yoshioka Shonan Kamakura General Hospital Stroke Center, Kamakura, Japan PURPOSE The aim of our study was to investigate whether or not time-intensity curve (TIC) of PWI can easily find salvageable penumbra in stroke patients due to acute carotid artery and ipsilateral middle cerebral artery occlusion. METHODS AND MATERIALS Included were patients 1) who were admitted within 3.5 hours of onset between Jan 2006 and January 2012, 2) who presented neurological symptoms of NIHSS >=5 on admission, 3) in whom emergency MRA displayed neither signal of the affected carotid artery nor the ipsilateral middle cerebral artery, and 4) who underwent PWI with Gd. We assessed, NIHSS on admission (NIH adm), DWI-ASPECT score, TIC types, neuroendovascular reperfusion therapy (RT) and NIHSS on the 7th day (NIH 7th). Early neurological improvement (ENI) was defined as NIH adm NIH 7th >0. TICs were generated on region of interests set at symmetrical positions of the bilateral MCA territories. According to the time to peak (TP) and the peak signal (PS) comparing the affected side (a) with the contralateral side (c), we classified TIC into four types and defined type 1 as TPa-TPc>2 and PSa <0.2xPSc, type2 as TPa - TPc>2 and 0.2xPSc2 and PSa >0.9xPSc, and type 4 as TPa-TPc <=2. Relationship between TIC types, RT and ENI were assessed. RESULTS Forty-nine patients were analyzed. There were 10, 31, 6 and 2 patients in TIC type 1, 2, 3 and 4, 19 patients underwent reperfusion therapy (RT) and 19 patients achieved ENI. Median DWI-ASPECTS was 4. RT coupled with TIC type 2 achieved ENI (p<0.01). CONCLUSION It was very easy to generate the TIC and to understand what the TIC meant. TIC type 2 may suggest salvageable penumbra. Keywords Acute stroke, MR perfusion, salvageable penumbra CO.08.07 PERIINTERVENTIONAL SAH DURING MECHANICAL THROMBECTOMY WITH STENTRETRIEVERS IN ACUTE STROKE. A RETROSPECTIVE CASE–CONTROL STUDY U. Yilmaz1, S. Walter2, H. Körner1, P. Papanagiotou3, C. Roth3, A. Simgen1, S. Behnke2, A. Ragoschke-Schumm2, K. Fassbender2, W. Reith1

Neuroradiology (2013) 55 (Suppl 1):S15–S159 1 Saarland University Hospital, Department of Neuroradiology, Homburg, Germany, 2Saarland University Hospital, Department of Neurology, Homburg, Germany, 3Klinikum Bremen Mitte, Department of Neuroradiology, Bremen, Germany

PURPOSE Mechanical thrombectomy with stentretrievers in acute stroke has emerged as a promising new technique with the highest recanalization rate of the therapeutic procedures available so far. However SAH on postprocedural CT-scans without angiographically recognizable perforations has been reported in up to 16 % of the cases and little is known about the influence of this finding on clinical outcome. The purpose of this study was to investigate the clinical relevance of SAH due to occult perforations during thrombectomy with stentretrievers. METHODS Postinterventional CT-scans of 217 consecutive patients with acute occlusions of intracerebral arteries who were treated with stentretrievers in our department between October 2009 and October 2012 were retrospectively analyzed. RESULTS SAH was found on postinterventional CT-scans in 4.1 % of the cases. 7 cases were included for further analysis and matched to controls. Comparison of the angiographic data of the two cohorts showed no significant difference in the length of the procedures or the number of maneuvers needed for recanalization. Neither were there significant differences in clinical outcomes as measured by NIHSS- and mRSscores. Secondary symptomatic ICH occurred in one case in either cohort and led to death in both cases. The rate of asymptomatic ICH within the first 24 h after recanalization was significantly higher in the group with periinterventional SAH (57 % vs. 0 %, P=0.018). CONCLUSION This small retrospective case–control study did not reveal a significant influence of periinterventional SAH due to angiographically occult perforations on neurologic outcome of patients treated with stentretrievers. Keywords Stroke, mechanical thrombectomy, SAH CO.08.08 THROMBUS DENSITY DOES NOT PREDICT ANGIOGRAPHIC RESULTS OF MECHANICAL THROMBECTOMY WITH STENTRETRIEVERS U. Yilmaz1, C. Roth2, W. Reith1, P. Papanagiotou2 1

Saarland University Hospital, Department of Neuroradiology, Homburg, Germany, 2Klinikum Bremen Mitte, Department of Neuroradiology, Bremen, Germany PURPOSE Mechanical thrombectomy with stentretrievers in acute stroke has emerged as a promising new technique with the highest recanalization rate of the therapeutic procedures available so far. However, in up to 20 % of the cases mechanical thrombectomy with stentretrievers results in poor angiographic outcomes with TICI-scores<= 2a. The purpose of this study was to investigate whether thrombus attenuation on the initial CT-scan can predict the angiographic outcome of the recanalization procedure in MCA-occlusions. METHODS The data of 70 patients with acute MCA-occlusions who underwent endovascular treatment with stentretrievers in our department were included. We analyzed thrombus attenuations, angiographic outcome and periprocedural thrombus fragmentation. RESULTS The mean thrombus attenuation was 49.8±7.8 HU and the mean difference to the attenuation of the contralateral MCA was 9.9±8.0 HU. There were no significant differences in the thrombus attenuations of

S69 occlusions that were successfully recanalized (mTICI>= 2b) and those that were not. Neither were there significant correlations of thrombus attenuations and periprocedural thrombus fragmentations which occurred in 64.3 %. We found a non-significantly higher rate of recanalizations mTICI>= 2b when the difference to the attenuation of the contralateral MCA was between 1 and 20 HU. CONCLUSION In contrast to results of other revascularization procedures as published in a recent study, the angiographic result of mechanical thrombectomy with stentretrievers is not predicted by thrombus attenuation Keywords Mechanical thrombectomy, stroke CO.08.09 SUSECEPTIBILITY WEIGHTED IMAGING (SWI) TO IDENTIFY IRREVERSIBLE INFARCTION F. Tsai1, H.W. Kao2, Y. Tsui3, C. Chen1 1 Taipei Medical University, Taipei, Taiwan, 2Triservice General Hospital of National Defensive Medical College, Taipei, Taiwan, 3Taipei Medical University, Chi-Mei Hospital, Taipei, Taiwan

Penumbra of brain is the potential salvageable ischemic brain tissue. Mismatch of parameters on perfusion weighted imaging and infarct core of diffusion weighted imaging has been used to define the penumbra as the therapeutic target. However, the clinical outcome varies despite successful recanalization with mismatch PWI/DWI. We investigated use of SWI to redefine the potential irreversible infarction. MATERIAL Retrospectively review 317 patients from January 2009 to December 2010.After excluding patients without proper SWI,49 patients(24 men,25 women; mean age 56.2 years and range15-89 years) with SWI and endovascular therapy were in this study. CT,SWI,DWI and FLAIR images were obtained for all before endovascular treatment. Fifteen patients(30.6 %) also undertook PWI before the procedure. Endovascular procedures were thrombolysis only in 39 patients(79.6 %) and combined thrombolysis and stenting in 10(20.4 %). RESULT Average timing of endovascular intervention was 6.3 hours after symptom onset and no significant different in timing between good and poor outcome.28 (51.7 %) patients who recovered well or stable condition had negative of deoxgenated cerebral arteries on SWI. 21(48.3 %) patients had poor outcome with extensive deoxygented cerebral arteries on SWI. CONCLUSION Deoxygenated cerebral artery will show as low intensity on SWI. Those patients who had poor outcome had extensive deoxygenated cerebral arteries indicating severe ischemic despite with mismatching of PWI/DWI. Thus SWI has potential biomarker to identify irreversible infarction and patients selection for endovascular procedure Keywords SWI, infarction, penumbra MONDAY, SEPTEMBER 30, 2013 – ROOM HZ 4 17:00–18:30 PARALLEL SCIENTIFIC SESSION - INFLAMMATORY DISEASE CO.09.01 CAN QUANTITATIVE MRI PREDICT CONTRAST ENHANCEMENT IN MULTIPLE SCLEROSIS? E. Hattingen 1 , U. Ziemann 2 , M. Hirschmann 1 , M. Wagner 1 , C. Schmidt1, A. Jurcoane1

S70 1 2

Neuroradiology, Goethe University Frankfurt, Frankfurt, Germany, Neurology, University Tübingen, Tübingen, Germany

PURPOSE Quantitative MR (qMRI) parameters - T1 relaxation time (T1), proton density (PD) and magnetization transfer ratio (MTR) - are influenced by structural tissue damages and extracellular water content which dependent on extracellular matrix and integrity of the blood brain barrier (BBB). Both of which are typical changes in multiple sclerosis (MS) lesions. Therefore, (semi)quantitative MR parameters (T1, PD, MTR) should reveal BBB damage, which can be quantified by the shortening of T1 relaxation time upon contrast agent. METHODS 17 patients with relapsing-remitting MS (RRMS, EDSS 1–3.5), 15 patients with progressive MS (PMS, EDSS 3–8.5) and 17 healthy controls were examined at 3 T with an 8-channel phased array head coil. T1, PD and MTR were measured and T1 was repeated 7 min after iv administration of gadolinium-based contrast agent. For T1 mapping, a variable flip angle method was performed together with B1-mapping correcting B1-inhomogeneities. For MTR, a 3D-GE sequence with slab selective excitation without and with MT saturation pulse was used. PD mapping was performed as descripted by Volz et al. (MRM 2012). Manually drawn MS FLAIR lesions were labeled as enhancing (E) if post-contrast T1-shortening was>2 SD above the mean T1-shortening in the normal appearing white matter (NAWM) and non-enhancing (NE) otherwise. RESULTS Pre-contrast T1, PD and MTR differed between E and NE in RRMS & PMS patients (all p<0.01). PD of E and NE differed between RRMS and PMS. In grey matter, pre-contrast T1 and MTR differed between RRMS and PMS and MTR differed between RRMS and controls. In NAWM, PD differed between PMS and controls and between PMS and RRMS, but not between RRMS and controls DISCUSSION QMRI may replace application of contrast agent to reveal BBB damage in MS lesions. BBB damage can be objectively measured as relative T1shortening upon standardized application of contrast agent, but also without contrast agent by PD, T1 and MTR provided that MS subtypes are considered. In addition, MTR is the most sensitive parameter for grey matter damage and higher PD values may be a sensitive indicator for advanced tissue damage in lesions and in NAWM of MS patients. Keywords Multiple sclerosis, quantitative MRI, blood brain barrier CO.09.02 REDUCED DIFFUSION ON MRI IN ACUTE MS LESIONS IS ASSOCIATED WITH CSF PLEOCYTOSIS P. Eisele, K. Szabo, M. Griebe, M. Wolf, M.G. Hennerici, A. Gass Dept. of Neurology, University Hospital Mannheim, Mannheim, Germany PURPOSE It is uncertain why acute multiple sclerosis (MS) lesions occasionally show a reduced apparent diffusion coefficient (ADC) on magnetic resonance imaging (MRI). The objective of the study was to investigate MRI diffusion characteristics of new acute MS lesions and compare them to cerebrospinal fluid (CSF) findings in patients with acute relapses. METHODS We compared CSF findings with conventional MRI and diffusion MRI signal characteristics of acute lesions in 25 patients with MS or a clinically isolated syndrome (CIS) lateron confirmed as MS. MRI studies were performed on a 1.5 T MR system using a standardized protocol including FLAIR, DWI and post-contrast T1-weighted MRI. The CSF was analysed for leukocyte count, CSF protein content and intrathecal IgG synthesis.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS In 9/25 patients investigated between days 1 and 4 after symptom onset, a reduced intralesional ADC value (−15 % to −51 %) was accompanied by a marked CSF pleocytosis (11–46 leukocytes / μl). In 16/25 patients with pseudo-normal or elevated ADC values in the acute lesion (range from 0 % to+52 %) there was no or only mild pleocytosis<10 leukocytes / μl (mean 3.1 / μl, range 1–8). These patients were investigated>5 days after symptom onset (range 6–8 days). CONCLUSIONS Our results suggest that ADC reduction in acute MS lesions is a phenomenon that is probably related to an aggressive inflammatory milieu as indirectly indicated by CSF pleocytosis. Furthermore the ADC reduction and CSF pleocytosis were only observed early after symptom onset, which suggests that both are typically early and transient phenomena. μμ Keywords Multiple sclerosis, diffusion weighted MRI CO.09.03 MRI FINDINGS IN PATIENTS WITH NEWLY DIAGNOSED NEUROPSYCHIATRIC LUPUS. A SYSTEMATIC APPROACH N. Sarbu1, P. Toledano2, S. Capurro1, M.I. Sarbu3, G. Espinosa2, R. Cervera2, N. Bargalló1 1

Hospital Clinic of Barcelona, Department of Radiology, Barcelona, Spain, 2Hospital Clinic of Barcelona, Department of Internal Medicine and Autoimmune Diseases, Barcelona, Spain, 3Consorci Mar Parc de Salut de Barcelona, Department of Rheumatology, Barcelona, Spain PURPOSE To evaluate structural brain abnormalities in newly diagnosed neuropsychiatric systemic lupus erythematosus (NPSLE). METHODS Retrospective descriptive study of 43 patients with NPSLE, studied between 2003–2011 in a national tertiary referral center for SLE. All MRI exams were performed within the first six months after the diagnosis of NPSLE. MRI studies were all performed at 1,5 T scan and included axial T1, T2 and FLAIR sequences in all the patients, DWI in 38 and post contrast T1 in 21. We arbitrary defined three types of lesions: small vessel, large vessel and inflammatory-type lesions. Small vessel type lesions were graded using the score of ARWMC from European Task Force that takes into account number and location. The large vessel lesions were classified by vascular territories and the inflammatory type lesion by localization and imaging characterization. Demographic, clinical data and laboratory parameters were also evaluated. A descriptive statistical study was performed using SPSS17.0. Correlation between MRI findings and clinical and laboratory data was made using Fisher’s exact test. RESULTS Cerebral abnormalities were present in 18 patients (41,9 %). According to the type of injury, vascular lesions were found in 17 patients (39,6 %), inflammatory in 3 (7 %), and in 2 (4,7 %) both type of lesions were found. Out of the vascular injuries, small vessel pattern was noticed in all the patients. The most common locations of small vessel lesions were: frontal (94,1 %), parieto-occipital (52,9 %), and infratentorial (29,4 %). Most patients (70,5 %) presented less than 15 lesions. Headache, cerebrovascular disease and seizure were the most prevalent NPSLE syndromes. Headache correlates with normal MRI exam (p=0,09). Patients with seizure had higher number of focal lesions (p = 0,02). Myelopathy syndrome was associated with contrastenhancement lesions (p=0,003). Related to laboratory data, patients with antiphospholipid antibodies showed a tendency to have more white matter changes than those without. Anti-dsDNA antibodies didn’t show any association with MR lesions.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSIONS A high number of patients presented MRI findings early after the diagnosis of NPSLE. The most frequent pattern consisted of small supratentorial white matter lesions, probably representing small vessel disease. Keywords Neuropsychiatric lupus, MRI, antibodies CO.09.04 LOCALIZED SCLERODERMA NEUROLOGICAL MANIFESTATIONS R. Carvalho1, F. Sousa2, J. Rocha2, J. Fernandes1, J. Rocha1 1 2

Neuroradiology Department, Hospital de Braga, Braga, Portugal, Neurology Department, Hospital de Braga, Braga, Portugal

PURPOSE Localized scleroderma “en coup de sabre” (LScs) is a rare chronic disease of probable autoimmune etiology. It presents as unilateral fronto-parietal atrophic lesions confined to the skin and underlying tissues, and differs from systemic forms by the absence of internal organ involvement. Recent data suggests that 20 % of the patients with localized forms, also have involvment of other systems, including the neurological, with epilepsy, headache or focal deficits. The imaging findings on MRI include focal atrophy and inflammatory lesions, even in asymptomatic patients. METHODS Presentation of imaging findings identified in four patients with LScs and neurological involvment. RESULTS Patient 1: 60 years old male admitted for transient ischemic attack (TIA) and vascular risk factors. He had left frontal skin atrophy, and the MRI revealed left fronto-perietal pachymeningeal enhancement and sulcal effacement. Patient 2: 46 years old female admitted for chronic headaches and right upper limb progressive paresis. The MRI revealed partially calcified left frontal intra-axial lesion. The lesion was surgically removed, and the histology revealed normal brain tissue, calcifications, and subtle inflammatory changes. The skin lesion and bone atrophy were subsequently identified. Patient 3: 29 years old female with recent worsening of chronic headaches. She was admitted for cerebral venous thrombosis. Right frontoparietal skin and bone atrophy were identified, and the MRI revealed multiple bilateral inflammatory lesions. Patient 4: 16 years old girl with history of visual aura migraine and right linear fronto-parietal skin atrophy. The MRI revealed right intra-axial enhancing lesions with surrounding edema. CONCLUSIONS The linear form of localized scleroderma may affect any part of the body, but when located in the head, may be accompained by CNS involvement. The patients described had no LScs previous diagnosis, and it was in the course of the etiology investigation of various neurological manifestations, associated with the recognition of the skin lesions, that this diagnosis of exclusion was reached. Treatment is difficult, and evolution of the skin and brain lesions can occur. Keywords Localized scleroderma, neurologic manifestations CO.09.05 COMBINED USE OF CONVENTIONAL MRI AND SPECTROSCOPY INCREASES DIAGNOSTIC ACCURACY IN AMYOTROPHIC LATERAL SCLEROSIS A. Cervo1, S. Cocozza1, F. Saccà2, S.M.D.A. Giorgio1, V. Brescia Morra2, E. Tedeschi1, A. Marsili2, G. Vacca2, A. Brunetti1, M. Quarantelli3

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Federico II University, Department of Advanced Biomedical Sciences, Naples, Italy, 2Federico II University, Department of Neurosciences, Reproductive Sciences and Odonto-Stomatology, Naples, Italy, 3National Research Council, Biostructure and Bioimaging Institute, Naples, Italy BACKGROUND AND PURPOSE Concerning amyotrophic lateral sclerosis (ALS) diagnosis, a number of conventional magnetic resonance imaging (MRI) signs and magnetic resonance spectroscopy (MRS) data modifications have been reported in literature, even if, taken alone, they do not provide an acceptable diagnostic accuracy. With the aim of improving diagnostic efficiency of MRI in ALS diagnosis, we combined a semiquantitative region of interest (ROI) based analysis of conventional MRI signs, such as hypointensity of the precentral gyrus and hyperintensity of the corticospinal tract in T2weighted images, with MRS data. MATERIALS AND METHODS A large group of subjects (74 ALS patients and 29 healthy controls HC) was split in two, in order to use two independent data sets, one for the definition of the optimal cut-offs to separate patients from HC (37 ALS patients and 14 HC), and the other for the assessment of the diagnostic accuracy of the MR measures (37 ALS patients and 15 HC). T2 hypointensity of the precentral gyrus and T2 hyperintensity of the corticospinal tract analyses were performed placing ROIs along the precentral gyrus and the corticospinal tract, respectively. MRS analysis was carried out averaging spectra from voxels of the motor cortex, using the corresponding N-Acetyl-Aspartate (NAA)/(Choline+Creatine) ratio as a marker of neuronal loss. RESULTS No significant difference emerged between ALS patients and HC in terms of corticospinal tract hyperintensity. Both NAA peak (p=0.023) and T2 hypointensity (p=0.024) of the precentral gyrus were significantly reduced in patients and did not correlate significantly to each other, suggesting their relative independence. When defining diagnostic accuracy of these two variables taken alone, we found a sensitivity and specificity of 45.9 % and 93.3 %, respectively, for both variables. When used in combination, we reached an increase in sensitivity (from 45.9 % to 70.3 %) without a significant loss in specificity. CONCLUSIONS Hypointensity of the precentral gyrus in T2 weighted images and NAA of the motor cortex reflect relatively independent phenomena, and their combined use improves the diagnostic accuracy of MRI in ALS diagnosis. Keywords Amyotrophic lateral sclerosis, magnetic resonance imaging, spectroscopy CO.09.06 CORRELATION OF EARLY CEREBRAL METABOLIC ALTERATIONS WITH IMMUNOLOGIC DATA AND COGNITIVE TESTS RESULTS IN NEUROLOGICALLY ASYMPTOMATIC HIV-1 POSITIVE AND HCV-POSITIVE PATIENTS J. Bladowska1, A. Zimny1, B. Knysz1, K. Malyszczak1, A. Koltowska1, P. Szewczyk1, J. Gasiorowski1, M. Furdal2, M. Sasiadek1 1 Wroclaw Medical University, Wroclaw, Poland, 2Regional Specialistic Hospital, Wroclaw, Poland

PURPOSE The aim of the study was to evaluate early cerebral metabolic changes using proton MR spectroscopy (MRS) in asymptomatic HIV-1-positive and HCV-positive patients without abnormalities in structural MR examination, as well as to assess the correlation between MRS measurements and the immunologic data and the cognitive tests results. METHODS Sixty-five asymptomatic patients: 21 HIV-1-positive naive, 20 HIV-1positive treated with combination antiretroviral therapy (cART), 9 HIV-

S72 1/HCV-positive naive, 15 HCV-positive naive and 18 normal control subjects were enrolled in the study. The MRS examinations were performed with a 1.5 T MR scanner. Voxels were located in the following regions: posterior cingulate gyrus (PCG), anterior cingulate gyrus (ACG), parietal white matter (PWM), left basal ganglia (BG) and frontal white matter (FWM). The NAA/Cr, Cho/Cr, mI/Cr ratios were calculated. Two cognitive tests: Wisconsin Card Sorting Test (WCST) as a measure of executive function and Brickenknap’s d2 concentration endurance test (d2 test) as a measure of visual attention were used in order to assess possible deterioration of cognitive functions. Correlations of MRS measurements with the immunologic data (CD4 nadir T cell count) and the cognitive tests results were analyzed. RESULTS There was a significant decrease (p<0.05) of the NAA/Cr ratios in PCG, ACG and PWM regions in HIV-1-positive cART treated and in the ACG area in HIV-1/HCV patients compared to the controls. The significantly decreased NAA/Cr ratios in PWM and FWM were observed in HCV infected patients. Other metabolite ratios in all analyzed regions showed no statistically significant differences. The decrease of CD4 nadir T cell count was associated with the decease of NAA/Cr ratio in the PCG area as well as the increase of Cho/Cr ratio in the FWM region in all HIV-1-positive subjects. We found significant correlations between NAA/Cr ratio in BG as well as Cho/Cr, mI/Cr ratios in PWM and BG regions and the cognitive tests results in HIV-1-positive and HCVpositive patients. CONCLUSIONS The metabolic changes in HIV-1 positive and HCV-positive patients are correlated with the results of the cognitive tests. The low CD4 nadir T cell count is a risk factor for neurocognitive impairment in HIV-1positive patients. Keywords HIV, HCV infection, brain metabolism, cognitive tests CO.09.07 DIFFUSION-WEIGHTED IMAGING APPEARANCE OF BALO’S CONCENTRIC SCLEROSIS: MULTIPLE STUDIES OF THREE INDIVIDUAL CASES R. Bert1, L. Gaido2, J. Corboy1 1

University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA, 2Denver Health, Denver, CO, USA PURPOSE Restricted diffusion demonstrated on diffusion-weighted imaging (DWI) sequences and apparent diffusion coefficient (ADC) maps associated with Multiple Sclerosis (MS) lesions has been presented by multiple authors. MS lesions with restricted diffusion studied longitudinally have demonstrated ADC signal evolution over time in temporal relationship to, but dynamically different than evolution of contrast enhancement. Balo’s Concentric Sclerrosis (BCS) is a rare form of MS with confluent intermittent disease resulting in alternating spreading rings of varying conventional MRI signals. Restricted diffusion has not been previously reported with BCS. Our purpose is to present three cases of BCS (two with successive studies) and compare enhancement, conventional MRI signal and DWI/ADC signal characteristics. METHODS Three subjects were referred to our large MS referral center after initial workup at other institutions. In one case, a biopsy had been performed to establish the diagnosis. Diagnosis was established in the remaining two cases by serial imaging, clinical exams and laboratory tests. Serial imaging studies included T2 FLAIR, T2 Fast Spin Echo, pre/post contrast T1 Spin Echo and DWI/ADC sequences. regions of interest (ROI) were obtained from concentric foci of varying signal on ADC maps and correlated with the other imaging sequences.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS In all three cases, alternating rings of high and low ADC were confirmed by ROI measurements. Low ADC rings increased in value gradually from the periphery to the center of the lesions. The established alternating rings of different DWI/ADC values persisted over the periods of observation. The outermost rings of DWI/ADC values varied at the time of presentation, two cases showing peripheral restricted diffusion and one showing vasogenic edema peripheral to restricted diffusion. Peripheral contrast enhancement was generally central to the most peripheral ring of restricted diffusion. DISCUSSION DWI/ADC images demonstrated classic concentric rings of varying DWI and ADC signal in BCS in all three cases. Restricted diffusion had only marginal overlap with contrast enhancement and evolved differently over time. We hypothesize that persistence of the ring pattern over time suggests a two phase pathologic process in this disease rather than waxing and waning of a single pathologic process. Keywords Balo's concentric sclerosis, multiple sclerosis, diffusion-weighted imaging CO.09.08 EVALUATION OF BRAIN VASCULARITY IN TB MENINGITIS USING MRI/MRA F. Abu Bakar1, K. Rahmat1, N. Ramli1, S. Tai Mi2, C. Tan2 1

Department of Biomedical Imaging, University Malaya Medical Centre, Kuala Lumpur, Malaysia, 2Department of Medical, University Malaya Medical Centre, Kuala Lumpur, Malaysia PURPOSE Cerebral vasculitis is one of the complications of tuberculous meningitis (TBM). Cerebral infarctions in TBM commonly affect the basal ganglia, thalamus and the internal capsule which are supplied by the penetrating striate vessels. The aim of this study is to evaluate the imaging features, vasculitic changes and dynamics of blood flow involved in tuberculous meningitis on MRI/MRA and consequently correlate with clinical outcome. MATERIALS AND METHODS A prospective study of newly diagnosed TB meningitis patients who presented to the University Malaya Medical Centre was undertaken between March 2012- February 2013. Diagnosis was confirmed by serum and cerebrospinal fluid analysis. Standard 3 T brain MRI sequences (T1W, T2W, Flair, DWI, GRE) and TOF MRA were performed at the time of diagnosis. RESULTS A total of six patients comprising four men and two women (range: 30– 60 years) were enrolled. 4 patients were healthy prior to diagnosis and two patients had co-morbid status. Acute cerebral infarctions were demonstrated in 5 patients, with 4 showing involvement of both anterior and posterior circulations territory. All patients with acute infarction in the anterior territory showed similar occurrence of infarction in what has been described as ‘TB zone’, referring to the heads of the caudate nuclei, anteromedial thalami and internal capsules. All patients demonstrated vasculitis in the anterior circulations mainly involving the M1, M2 and A1 segments. Vasculitis in the anterior and posterior circulations was observed in 3 patients. Acute obstructive hydrocephalus was present in 5 patients. Leptomeningeal and basal cisterns enhancement and tuberculomas were demonstrated in all patients. CONCLUSION MRI/ MRA of the brain findings are characteristic in tuberculous meningitis and vasculitis. Vascular abnormality mainly affected the middle cerebral, anterior cerebral and supraclinoid internal carotid arteries. Keywords TB meningitis, vasculitis, infarct

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CO.09.09 AGE-RELATED DTI CHANGES IN THE DEEP GRAY NUCLEI C. Lee1, K.M. Ng2, R. Helmut1, C.S. Yeoh1, E.K. Tan2,3, L.L. Chan1,2 1 Department of Radiology, Singapore General Hospital, Singapore, Singapore, 2 Duke-NUS Graduate Medical School, Singapore, Singapore, 3Department of Neurology, National Neuroscience Institute (SGH-Campus), Singapore, Singapore

INTRODUCTION Diffusion Tensor Imaging (DTI) is widely used in the study of normal aging of white matter, and the DTI parametrics of lower fractional anisotropy (FA) and higher apparent diffusion coefficient (ADC) are typically reported. However the effects of aging on the deep gray structures are less known. PURPOSE Aim of this study us to report the effects of aging on the DTI parametrics of anisotropy or diffusivity in the deep gray nuclei or the brain of the longitudinal case series. METHODS Twenty healthy and neurologically intact control subjects (age 46–73years, average 60 years, 12 males) underwent brain T1-, T2-weighted and DTI scan, followed by an identical scan 6.6 (5–7) years later on a 1.5 Tesla MR scanner. Six regions of interest were drawen in the caudate nucleus, putamen and thalamus bilaterally using the commercially available Siemens Neuro 3D Taskcard, and the FA and ADC values recorded. The values from the right and left side for each structure were averaged and statistical analysis was performed using the paired student t-test. Statistical significance was defined at p<0.05. RESULTS Mean FA in the caudate measured 0.25±0.033 (0.20-0.30), putamen 0.24±0.027 (0.20-0.29), thalamus 0.37±0.059 (0.29-0.47). Mean ADC in the caudate measured 0.72±0.040 x 10-3 mm2/s (0.670.81), putamen 0.67± 0.034× 10-3 mm2/s (0.61-0.77) and thalamus 0.71±0.060 x10-3 mm2/s (0.63-0.84). These DTI metrics increased in all the structures studied on the longitudinal follow up study. The serial increase in the FA and ADC were statistically significant for all structures except the ADC of the caudate. CONCLUSIONS In contrast to normal white matter there is an increase in both anisotropy or diffusivity in the deep gray nuclei with increase in age. This may be related to the notable increase in iron deposition in the deep gray matter structures with advancing age. Keywords DTI, brain, aging TUESDAY, OCTOBER 1, 2013 – ROOM HZ 3 09:00–10:00 IMAGING IN PSYCHIATRY S.34.01 MICROARCHITECTURE OF HIPPOCAMPUS: HOW MUCH CAN BE RESOLVED ON CLINICAL 3 T MRI?

S73 clinical high resolution MRI. Hence, there are no consistent and objective criteria for evaluating hippocampal architecture on clinical MRI. This study attempts to assess the extent to which the microanatomy of hippocampus can be resolved on high resolution techniques at 3 T and thereby, establish clinical MR criteria of hippocampal architecture. METHODS 95 consecutive technically optimal 3 T MRI (SKYRA, SIEMENS)scans of patients with seizures were independently viewed by two neuroradiologists experienced in epilepsy imaging. Hippocamapal architecture was evaluated on high-resolution coronal 3D SPACE True Inversion Recovery T1 sequence. A total of 154 hippocampi remote or contralateral to seizure onset, and appearing normal in volume and signal were included in the study. These hippocampi were scrutinized for morphological details published in cadaveric ultra high field MR and histologic studies of hippocampal architecture. RESULTS The following features of hippocampal microarchitecture were agreed upon by both observers in greater than 95 % hippocampi:

1.

Cornu ammonis (CA1-CA3):

a.

2.

A dark outer stripe representing the strata oriens and pyramidale, tapering from CA1 to CA3 b. An inner bright stripe comprising of strata radiatum and lacunosum-moleculare, becoming thicker from CA1 to CA3. End-folium (CA4 and dentate gyrus):

a.

Dentate gyrus: an outer bright molecular layer, and inner dark band comprising of granular and polymorphic layers b. CA4: seen as an intermediate signal zone enveloped by the dentate gyrus. In the hippocampal head digitations, the bright stripes of inner cornu ammonis and outer dentate merge into a single band; while in the body, these are separated by the hippocampal fissure. CONCLUSION High resolution 3 T MRI can reliably replicate the above details of hippocampal microarchitecture described on cadaveric MR and histological studies. These can be used as objective criteria to evalaute and describe hippocampal architecture both in practice and clinical research. Keywords Epilepsy, hippocampus, MRI S.34.02 NO DIFFERENCE OF GREY MATTER DISTRIBUTION COMPARED TO CONTROLS BUT REGIONALLYACCENTUATED REVERSIBLE BRAIN GREY MATTER REDUCTION IN ULTRA MARATHON RUNNERS DETECTED BY VOXEL BASED MORPHOMETRY W. Freund1, S. Faust1, F. Birklein2, C. Billich1, A. Wunderlich1, U. Schuetz1 1

V. Gupta, P. Vibhute

Diagnostic and Interventional Radiology, University Hospitals Ulm, Ulm, Germany, 2Neurology, University Medical Centre Mainz, Mainz, Germany

Mayo Clinic, Radiology, Jacksonville, Fl, USA PURPOSE Alterations of hippocampal volume and signal are the standard MR criteria in localization of temporal lobe epilepsy. In absence of the above, the internal architecture of hippocampus may become critical in seizure lateralization. Although, the hippocampal microanatomy is well understood, there is no literature investigating what extent of the microarchitecture detail is reproducible on

PURPOSE During the 4,487 km ultra marathon TransEurope-FootRace 2009 (TEFR09), runners showed catabolism with considerable reduction of body mass. We hypothesized that the athletes have acquired changes to grey matter (GM) brain morphology due continuous high volume training. With VBM we looked for possible baseline differences of athletes´ brain composition compared to controls as well as the evolution of additional changes during the race.

S74 MATERIAL AND METHODS Prior to the start of the race 13 runners volunteered to participate in this study of planned brain scans before, twice during, and 8 months after the race. A group of matched controls was recruited for comparison. Twelve runners had a scan before the start of the race and were taken into account for comparison with control persons. Because of drop-outs during the race, voxel based morphometry (VBM) analyses could be performed in 10 runners covering the first 3 time points, and in 7 runners who also had the follow-up scan. Scanning was performed with three identical 1.5 T Siemens Avanto scanners, two situated at our university. The third MRI scanner with identical sequence parameters was a mobile MRI unit escorting the runners. A volumetric 3D dataset was imaged using a MPRAGE sequence. A level of p<0.05, family-wise corrected for multiple comparisons was the a priori set statistical threshold. RESULTS Comparison of TEFR09 participants and controls revealed no significant differences regarding the GM brain volume. During the race however, voxelwise morphometry revealed GM concentration decreases in regionally distributed brain regions. These included the bilateral posterior temporal and occipitoparietal cortices as well as anterior cingulate and caudate nucleus. After eight months, regional GM differences came back to baseline. CONCLUSION We did not observe baseline differences between TEFR09 athletes and rather sedentary controls. However, during the race GM concentration decreased in brain regions normally associated with higher visuospatial and language tasks. Also the possible reduction of the energy intensive default mode network as a means to conserve energy during catabolism is discussed. These changes are reversible after 8 months and seem to be adaptive. Keywords Voxel based morphometry, ultra marathon, atrophy TUESDAY, OCTOBER 1, 2013 – ROOM HZ 3 10:30–12:00 PARALLEL SCIENTIFIC SESSION - ADVANCED IMAGING: FUTURE TECHNIQUES IN NEURORADIOLOGY CO.10.01 EVALUATION OF THE PONTINE PERFORATORS OF THE BASILAR ARTERY USING DIGITAL SUBTRACTION ANGIOGRAPHY IN HIGH RESOLUTION AND 3D-ROTATION TECHNIQUE S. Lescher, T. Samaan, J. Berkefeld Institute of Neuroradiology, Frankfurt Am Main, Germany PURPOSE The microvascular anatomy of the proximal and the middle portion of the basilar artery have been described and classified from different point of views before (Foix and Hillemand (1925), Gillilan (1964) and Lazorthes et al. (1976)). The superficial ramifications of the arteries and their points of penetration have similar patterns to the spinal cord vascular supply. They can be divided into subgroups according to their penetrations of brain stem surfaces. Existing imaging of the brain stem is missing in detail descriptions of the small arterial rami origin from the basilar artery. The lack of consistent presentation in the imaging literature raised the question whether latest generation of flat panel neuroangiography allows for more reliable visualisation of the pontine branches of the basilar artery. METHODS We analysed DSA-images and 3D rotational angiography reconstructions obtained on a Siemens AXIOM Zee biplane neuroradiological angiography equipment. All patients whose DSA images were chosen for retrospective evaluation had clear indications justifying the performance of a selective vertebral angiogram.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS On DSA images small arterial side branches of the basilar artery with superficial courses can be demonstrated in each of the cases but with a wide variation in the visibility of these vessels. The basic patterns are segmental circumferential arteries on each side with a descending course around the pons. Common trunks or longitudinal anastomoses between the circumferential arteries are occasionally seen but the frequency varies considerably. Paramedian perforating branches penetrating the brain stem can be identified on three levels and are subdivided in a cranial, medial and caudal group. CONCLUSIONS Our results demonstrate that 3D-rotation technique is able to visualize reliable the penetrating branches of the brainstem in vivo. In future more detailed information on DSA images about the anatomy of the perforator arteries can provide further explanations about the arterial territories in brain stem and their correlation to ischaemic lesions in brain stem infarctions or after intracranial stenting. The clinical significance of imaging the microvascular anatomy of the brain stem, their possibilities and their limitations should be demonstrated in further studies. Keywords Pontine perforators, basilar artery, 3D-rotation technique CO.10.02 A COMPARATIVE PHANTOM STUDY ON RADIATION EFFECTIVE DOSES OF CEREBRAL HEMODYNAMICS MEASUREMENT BETWEEN DYNA CTAND MULTIDETECTOR CT W. Guo1, C. Lin1,2, W. Chen3, S. Hung1,2, W. Chu1, C. Chiu1, T. Wu3 Taipei Veterans General Hospital, Taipei, Taiwan, 2School of Medicine, National Yang-Ming University, Taipei, Taiwan, 3Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan 1

PURPOSE Digital subtractive angiography (DSA) using Dyna CT provides both conventional morphological and quantitative hemodynamics in onestop. However, the effective radiation dose remains the concern. We aimed to estimate effective dose that involved in cerebral hemodynamic measurement using Dyna CT and multidetector CT (MDCT). METHODS An anthropomorphic phantom (Rando Alderson phantom; Radiology Support Devices, Long Beach, CA), a biplane Dyna-CT DSA suite (AXIOM-Artis®, Siemens Healthcare, Erlangen, Germany) and a 256 slice MDCT (Brilliance iCT®, Phillips Healthcare, Best, Netherland) were used. For cerebral parenchyma blood volume (PBV) measurement, a clinical DSA imaging protocol (one 8-second rotational mask run with 60 frames/second followed by another 8-second rotational contrast medium filled run with same frame rate) was used. The scanning parameters were: 73 kV, 483 mA, 4.0 ms, 48 cm field-of-view. The scan range was 8-cm slab (from sella turcica to convexity). Eighty lithium fluoride thermo-luminescent dosimeters (TLDs) (TLD-100H, Bicron-Harshaw, Solon, OH) divided into 22 organ sites were embedded in the phantom. The same phantom and TLDs distribution were also scanned with the MDCT using a clinical CT perfusion (CTP) scanning protocol (8-cm scan coverage identical to PBV, 5 mm slice thickness, 64x1.25 mm collimation, 20x20 cm FOV, 80 kVp, 250 mA, 100 mAs, 0.4 second tube rotation time, scan interval of 1.5 seconds and lasted for 1 minute). We followed the guidelines of International Commission on Radiation Protection Number 103 (ICRP-103) to measure the effective dose. Both Dyna CT and MDCT dose experiments were conducted twice. RESULTS The dose area product/entrance skin dose was 2631.6 μGym2/228 mGy and the effective dose was 0.87±0.55 mSv for PBV. As a comparison, the dose length product of MDCT CTP was 1177.3-1232.9 mGy*cm,

Neuroradiology (2013) 55 (Suppl 1):S15–S159 equivalent to the effective dose of 2.46-2.58 mSv. The effective dose of MDCT CTP measured by TLDs was 2.77±1.59 mSv. CONCLUSIONS Cerebral PBV measurement using Dyna-CT is dose-saving with high reproducibility and reliability. Its one-stop imaging service saves procedural time and patient transportation and makes Dyna CT be recommended for cerebral vascular disorders. Keywords Effective irradiation dose, dyna CT, parenchymal blood volume CO.10.03 NEUROSURGICAL ICU: ULTRA-LOW DOSE SAFIRE BASED HEAD CT SATISFACTORY FOR REPEATED SURVEILLANCE EXAMS I. Corcuera-Solano, A. Noor, A. Doshi, L. Tanenbaum Icahn School of Medicine at Mount Sinai, New York, NY, USA PURPOSE Neurosurgical ICU(NICU) patients undergo frequent and repeated head CT imaging, resulting in high cumulative doses. As a result, we adopted a sinogram affirmed iterative reconstruction based (SAFIRE) ultra-low dose head CT protocol (ULDCT) for follow-up use in this patient population. Our purpose was to quantitatively and qualitatively assess the quality of ULDCT exams against perceived standards of quality as well as with respect to LDCT and SDCT examinations of the same patient. METHOD AND MATERIALS Due to practical considerations and scanner availability, NICU patients undergo CT exams on a variety of scanners and many will undergo lowdose CT (LDCT) and standard-dose (SDCT) along with ULDCT examinations creating the opportunity to assess an individual patient's image quality across exam types. A retrospective analysis of 60 head CT during 2012–2013 was performed with 28 ULDCT (avg CTDIvol =15.55 mGy, 79 %
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Diagnostic and Interventional Radiology, University Hospitals Ulm, Ulm, Germany, 2Neurosurgery, Nova Clinic, Biberach, Germany, 3 Neurosurgery, University Hospitals Ulm, Ulm, Germany, 4Neuroradiology, University Hospitals Ulm, Ulm, Germany BACKGROUND Angulated projections are standard in conventional radiography of the cervical spine. However, they are not widely used in magnetic resonance imaging (MRI). Since neuroforaminal pathology is responsible for many causes of radiculopathy, improved visualization of the neuroforamen is necessary. Especially in the neurosurgical setting, it is important to discern the degree of neuroforaminal stenosis and the cause (osseous or soft). PATIENTS AND METHODS In a retrospective setting, 25 consecutive patients diagnosed with cervical monoradiculopathy were identified after approval of the study by the local ethics committee. T2-weighted sagittal, coronal oblique and transversal slices were anonymized, generating 75 “cases” consisting of stacks of slices in only one spatial orientation. Four readers blinded to the diagnosis individually performed the evaluation (2 radiologists and 2 neurosurgeons, one of each pair experienced with the coronal oblique slices; the naïve received a 10-minute training). Rating criteria were site and grading of the predominant neuroforaminal stenosis, cause of stenosis and the level of confidence on a 100-point visual analogue scale (VAS). The results were compared to the clinical gold standard of the final neurological diagnosis. Comparisons were performed with ttests, taking a level of p<.05 as statistically significant. Interrater agreement was computed. RESULTS Using only one orientation, the sensitivity to diagnose the relevant neuroforaminal stenosis was .45 for transversal, .63 for sagittal and .61 for coronal oblique scans. The combination of three planes increased sensitivity to .77 to detect the relevant lesion in at least one sequence. The readers felt significantly most confidence in the attribution of the cause of neuroforaminal pathology on coronal oblique planes (76.4 VAS points, p=.006) vs. 68.2 (sagittal) vs. 68.6 (transversal). Neither experience with the sequence nor the professional status resulted in significant differences in the fraction of correct diagnoses (range 51-59 %), however, interrater agreement was significantly better for experienced readers (kappa .48 vs .32 for inexperienced readers, p=.02). CONCLUSION Coronal oblique planes in cervical spine MRI provide valuable additional information and improve confidence in the attribution of the cause of neuroforaminal obstruction as well as sensitivity towards detection of relevant neuroforaminal pathology. Coronal oblique planes are easy to interpret, however, experience with the sequence increases interrater agreement. Keywords MRI, cervical spine, neuroforamen CO.10.05 QUANTITATIVE CEREBRAL ANGIOGRAPHY TO EVALUATE HYPERPERFUSION POSTCAROTID STENTING F. Tsai1, B.C.J. Lin2, F.C. Chang2, W.Y. Guo1,2, D.Y.T. Chen1 1

Taipei Medical University, Imaging Research Center, Taipei, Taiwan, Taipei Veterans General Hospital, Radiology Department, Taipei, Taiwan 2

Cerebral circulation is usually in stable even with increase cerebral blood flow after endovascular stenting procedure. In some occasions, hyperperfusion syndrome might develop, but symptoms of

S76 hyperperfusion may be cured or subsided after proper management with blood pressure control. However, we have observed abnormal venous drainage with severe hypoplasia ipsilateral dural sinus associate with those devastating complication.Thus promote us to review all cases over the past two years, hoping to get possible factor of hyperperfusion from carotid stenting with impairment of venous drainage. MATERIALS AND METHODS We have retrospectively reviewed 42 patients from the past two years. Among these 42 patients; F:M being 7:35 and mean age 73.6 years and ranged from 51 to 81 years of age. All patients had MR and sonographic evidence of unilateral carotid stenosis more than 70 % according to NASCET criteria with clinical symptoms of minor stroke(45 %),TIA(72 %) and dizziness (81 %). Quantitative color coded cerebral angiography were applied to measure changes of cerebral circulation especially at cerebral venous drainage. Among of 39 of those 42patients had quantitative color coded cerebral angiography before and after carotid stenting procedures and also MRI. Arterial and venous circulation were compared with before and after stenting procedure and also changes of MRI findings RESULTS AND DISCUSSION All patients had shortening of arterial circulation but venous circulations were irregular with those patients had ipsilateral hypoplasia of dural sinus. These group had some shortening, stable and also delay venous flow even increasing arterial flow. Those patients who had hypoplasia or atresia of ipsilateral dural sinus had shortening of venous circulation also had MRI finding of increasing white matter changes and symptom of hyperperfusion,but not with others. Hemorrhagic complication may occur with pressure gradient from atresia of ipsilateral dural sinus. We believe that quantitative color coded cerebral angiography may be able to identify those patients with potential hyperperfusion and with proper management immediately to avoid complication. Keywords Stenting, hyperperfusion, sinus atresia CO.10.06 DIFFERENTIAL DIAGNOSIS OF BRAIN LESIONS USING MRI, PROTON MR SPECTROSCOPY (MRS) AND INTERPRET DECISION SUPPORT SYSTEM (DSS). A COMPARATIVE STUDY R. Romanos-Zapata, F. Ortiz-Nieto, R. Raininko Uppsala University - Department of Radiology, Uppsala, Sweden PURPOSE MRS, commonly used in research, is not so common in daily clinical practice. INTERPRET DSS was developed to improve diagnostic capability of MRS, particularly in intracranial tumors. The purpose of our study was to evaluate the utility of MRS as an additional method in clinically problematic cases and how using of INTERPRET DSS can improve diagnostics. METHODS Journals of the patients examined with MRS for clinical indications, often with uncertain MRI diagnosis, were reviewed. Teenagers and adults with a confirmed diagnosis of a disease included in the INTERPRET database and examined with a single voxel MRS were included in the study. The final material consisted of 30 patients. The single voxel MRS (PRESS sequence, TR/TE 5000/30 ms, 1.5 T) was analyzed with LCModel. Thirteen patients had also examined with CSI (TR/TE 1500/144 ms). MR images were re-evaluated by one experienced neuroradiologist as in clinical work: referrals and earlier radiological examinations were available. Then MRS data was reanalyzed. Another radiologist compared the MRS curves in DSS database. Both radiologists were blinded for the

Neuroradiology (2013) 55 (Suppl 1):S15–S159 confirmed diagnoses. The MRI, MRS and DSS diagnoses were compared to the confirmed diagnosis achieved by histopathology in 27/30 patients, long time follow-up in 2 patients and laboratory tests in one patient. Diagnoses were classified as non-neoplastic disease, low grade tumor (Gr I-II), and high grade tumor (Gr III-IV). Specific DSS and confirmed diagnoses were also compared. RESULTS 21 patients had a high-grade tumor which class of diagnosis was given correctly in 13 cases (61 %) on MRI, in 11 cases (52 %) after MRS analysis, and in 13 cases (61 %) when DSS was used. Five patients had low-grade tumors which were correctly diagnosed in 1/5 cases on MRI, in 2/5 cases with MRS and in 3/5 cases using DSS. Non-neoplastic disease group was correctly diagnosed in all 4 cases on MRI, in 3/4 with MRS and in 2/4 using DSS. When the results were compared to specific diagnoses, DSS gave a correct diagnosis in 11/30 examinations (36 %). CONCLUSION In clinical material, MRS did not improve differential diagnostic capability of MRI and INTERPRET DSS did not give significantly better results than visual MRS analysis. Keywords Magnetic resonance, spectroscopy, brain CO.10.07 BRAIN CHANGES IN KALLMANN SYNDROME A. Salvalaggio1, R. Manara2,3, A. Favaro1, V. Palumbo4, C. Idotta1, V. Citton3, A. D'Errico5, A. Elefante5, G. Ottaviano6, E. Cantone5, C. Briani1, N.A. Greggio7, L. Weis3, S. Rizzati8, E. Napoli9, G. Coppola10, A. Brunetti5, F. Di Salle2, G. Bonanni8, A.A. Sinisi4 1

Dept of Neurosciences, University of Padova, Padova, Italy, Neuroradiology, University of Salerno, Salerno, Italy, 3IRCCS San Camillo, Venezia, Venezia, Italy, 4Endocrinology and Medical Andrology, Second University of Napoli, Napoli, Italy, 5Federico II University, Napoli, Napoli, Italy, 6Otolaryngology Section, Dept of Neurosciences, University of Padova, Padova, Italy, 7UOS di Endocrinolgia Pediatrica, Azienda Ospedaliera, Padova, Italy, 8Dept of Medicine (DIMED), University of Padova, Padova, Italy, 9Medicanova, Diagnostic Center, Battipaglia, Salerno, Italy, 10Child and Adolescent Neuropsychiatry, University of Salerno, Salerno, Italy 2

BACKGROUND Kallmann syndrome (KS) is a rare inherited disorder due to defective intrauterine migration of olfactory axons and gonadotropin-releasing hormone neurons leading to rhinencephalon hypoplasia and hypogonadropic hypogonadism. Concomitant brain developmental abnormalities have been described. AIMS to investigate KS-related brain changes by means of conventional and novel quantitative MRI analyses. Material and methods: Forty-five male KS patients (mean-age 30.7 years; range: 9–55) and twenty-three age-matched male controls underwent brain MRI (Achieva 1.5 T, Philips). The MRI study protocol included 3D-T1, FLAIR and diffusion tensor imaging (32 non-collinear gradient encoding directions; b-value=800 s/mm2). Voxel based morphometry, sulcation, curvature and cortical thickness analyses and tract based spatial statistics were performed using SPM8, Freesurfer and FSL. RESULTS Corpus callosum partial agenesis, multiple-sclerosis-like white matter abnormalities and acoustic schwannoma were found in one patient each. Total amount of gray and white matter volume and TBSS measures (fractional anisotropy and mean, radial and axial diffusivity) did not differ between KS patients and controls. By specific analyses, KS patients presented with: symmetric clusters of gray matter volume increase and decrease and white matter volume decrease close to the

Neuroradiology (2013) 55 (Suppl 1):S15–S159 olfactory sulci; reduced sulcal depth of the olfactory sulci and deeper medial orbitofrontal sulci; lesser curvature of olfactory sulcus and sharper curvature close to the medial orbitofrontal sulcus; increased cortical thickness within the olfactory sulcus. CONCLUSIONS This large MRI study on male KS patients featured significant morphological and structural brain changes, likely driven by olfactory bulb hypo/aplasia, selectively involving the basal forebrain cortex. Keywords Kallmann syndrome, MRI, mirror movements CO.10.08 VISUALIZING PLASTICITY AND ALTERED NEURONAL SIGNALING IN THE INJURED HUMAN SPINAL CORD WITH fMRI D. Cadotte1, D. Mikulis2, R. Bosma3, P. Stroman3, M. Fehlings1 1

University of Toronto, Dept. of Surgery, Division of Neurosurgery, Toronto, Canada, 2University of Toronto, Department of Radiology, Division of Neuroradiology, Toronto, Canada, 3Queens University, Kingston, Canada PURPOSE Evidence of CNS plasticity after traumatic spinal cord injury has been observed in animal models and human brain fMRI studies. In this work, we conduct a spinal fMRI study and apply a functional connectivity analysis to determine whether or not the injured spinal cord processes sensory information differently than healthy controls. METHODS

S77 Using an automated thermal delivery system, heat (44 °C) was applied to 2 dermatomes above and 2 below the level of SCI. Spinal fMRI data was collected on a 3 T system using a SEEPbased protocol developed by our group (SSFSE, TE=30 msec, TR=1 sec). Data were spatially normalized and analyzed using the general linear model (P=0.001). We divided the cervical spinal cord into zones based on known anatomical relationships of nerve rootlets entering the cord from the segmental nerve root. We conducted a functional connectivity analysis between the dorsal quadrant of the spinal cord corresponding to the stimulated dermatome and other regions of the spinal cord and brainstem. Clinical measures were conducted at the time of scan (AISA examination). RESULTS 35 people were examined: 20 control, 9 incomplete SCI and 6 ASIA E patients. We demonstrate that dermatomes of abnormal sensation negatively correlate with the number of active voxels (R2 = 0.93, p < 0.001). We show that the number of interspinal connections is significantly higher in incomplete SCI patients stimulated above the level of their injury in a dermatome of normal sensation, p= 0.045, in comparison to healthy controls. This was also observed in ASIA E patients (p=0.03). CONCLUSIONS For the first time, we report a connectivity analysis of spinal fMRI data to understand how neural networks change after spinal cord injury. We show for evidence for spinal plasticity in incomplete SCI patients; these plastic changes are evident in those who fully recover from their injury. Keywords Spinal cord injury, fMRI, plasticity

S78

Neuroradiology (2013) 55 (Suppl 1):S15–S159

Scientific paper poster session (original and unedited texts as received by the authors)

Brain tumors, diagnostic and interventional P.1.001 SELECTIVE EMBOLIZATION OF NECK OF INTRACRANIAL ANEURYSMS WITH PLATINUM COILS M. Wu1, C. Shen1, Y. Tyan1, H. Wong2 1

Department of Medical Imaging, Chung Shan Medical University Hospital and Institute of Medicine, CSMU, Taichung, Taiwan, 2Department of Neuroradiology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan PURPOSE Dense packing is acknowledged the goal in endovascular treatment of the intracranial aneurysm. Instead of attempting to achieve a dense packing of the whole aneurysm, selective maximal packing for the aneurymsal neck was achieved. The purpose of this study was to evaluate the outcome of aneurysms treated by this method. METHODS Eight patients with seven ruptured and one unruptured aneurysms. All aneurysms with lobulated outline and present of daughter sac were treated with selective embolization, coiling was reduced for the daughter sac or the aneurysm fundus, but maximal packing was achieved for the aneurysmal neck. RESULTS Seven aneurysms were shown to have complete occlusion on angiograms obtained at the end of the procedure. Only one aneurysm revealed the contrast stasis in lobulated daughter sac. The follow-up studies show a stable complete occlusion and no rebleeding clinically. CONCLUSIONS The selective embolization of the aneurysm seems to enable a change in the concept of coiling, by reducing the amount of coils and avoid perforation during manipulation of the coil within the daughter sac. Keywords Aneurysm, embolization, coil P.1.002 IMAGING REVIEW OF DYSEMBRYOPLASTIC NEUROEPITHELIAL TUMOR (DNET)

seizures. The purpose of this report is to review the imaging findings of this tumor in a large cohort. METHOD AND MATERIALS The study was IRB-approved. 50 pathologically-proven cases of DNET presenting at 2 large pediatric medical centers from 1998– 2011 were identified from a review of neuro-oncology databases. Pre-operative imaging was available on 37 cases (34 MRI, 11 CT). Imaging features were evaluated independently by 2 pediatric radiologists, documenting size, location, signal characteristics, the presence of edema, calcification, and cystic features. Presence and degree of enhancement were also assessed, as well as presence of diffusion restriction, and features on MR perfusion and spectroscopy, when available. RESULTS 22 of the tumors were in the frontal lobes, 11 temporal, 3 parietal, and 5 occipital, with no predominant side. 34 of 37 cases were either cortically based tumors, or mixed cortical and subcortical. One was intraventricular. Tumor diameters ranged from 4 - 83 mm, with an average of 25 mm. Most were elongated spheres, often conforming to the morphology of the involved gyrus. Of those that had CT, all but one were hypoattenuating; the exception was diffusely calcified. All but 1 were considered well-defined lesions, with clear delineation from surrounding parenchyma. 30 had hypo-intense signal on T1WI with 27 having associated hyperintense signal on T2WI or FLAIR. 10 had iso- or hypo-intense FLAIR signal. Only 2 cases had vasogenic edema, and less than half demonstrated enhancement. Cyst-like foci were seen in a small number of cases, but were not a dominant feature. No tumors exhibited diffusion restriction. MRS showed a relatively benign spectrum, without lactate or choline elevation. MR perfusion (2) showed no significant altered perfusion in the tumors. CONCLUSION Although there is considerable variability in the imaging appearance of DNET, the majority are cortically based lesions in the supratentorial compartment, usually frontal or temporal, averaging 2-3 cm in diameter, with hypointense signal on T1WI and hyperintense signal on T2WI. The presence and pattern of enhancement is variable, and cystic foci or calcification are occasionally seen. Keywords DNET, pediatric, brain tumor

University Hospital, Cincinnati, OH, USA, 2Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA

P.1.003 PROGNOSTIC VALUE OF MRI DSC-T2* CEREBRAL PERFUSION IN GBM (GLIOBLASTOMA MULTIFORME) PATIENTS

PURPOSE Dysembryoplastic neuroepithelial tumors are low-grade neoplasms frequently associated with cortical dysplasia and typically present with

J. Villanua1, E. Fernandez1, J. Larrea2, E. Pardo2, P. Aldaz3, C. Barrena4, E. Carrasco3, E. Sarasqueta5, I. Ruiz6, A. Matheu3

L. Wang1, B. Jones2, K. Dorris2 1

Neuroradiology (2013) 55 (Suppl 1):S15–S159 1 Unidad Donostia, Osatek Sa. Donostia University Hospital, Donostia-Ss, Spain, 2Radiology Department, Donostia University Hospital, DonostiaSs, Spain, 3Neurooncology Group, Biodonostia Institute, Donostia University Hospital, Donostia-Ss, Spain, 4Neurosurgery Department. Donostia University Hospital, Donostia-Ss, Spain, 5Epidemiology Department. Donostia University Hospital, Donostia-Ss, Spain, 6Pathology Department, Donostia University Hospital, Donostia-Ss, Spain

PURPOSE Determine the prognostic value of MRI DSC-T2* cerebral perfusion in GBM patients three months after the end of Chemo & Radiotherapy (QT&RT). METHODS We performed a retrospective study of 103 patients diagnosed by surgical intervention of GBM between March 2007 and November 2012. From them 63 patients completed QT&RT. In 37 subjects MRI DSC-T2* cerebral perfusion studies were obtained three months after the end of QT&RT. EGFR and TP53 expression was analyzed by Immunohistochemistry in these group of patients. We performed the Kaplan-Meier and Log rank test for rCBV >2,7 subjects (n=17) and rCBV<=2,7 (n=20) patients groups (pg). Additionally, the correlation of rCBV with EGFR high expression-EGFRh (n=15) and P53 mutation (n=30 positive-P53mp, N =7 negativeP53mn) has been studied. RESULTS The overall median survival rate (msr) of the 37 patients examined by MRI DSC-T2* three months after QT&RT, was 517 days (d) (474,3559,7). The rCBV>2,7 pg (n=17) shows a msr of 456 d (454–457) vs rCBV<=2,7 (n=20) pg with a msr of 577,0 d (384,7-769,3), p (Log Rank)=0,006. EGFRh was found in 66,7 % (n=10) and P53mp in 50 % (n=15) of the rCBV>2,7 pg. In contrast, EGFRh was detected in 33,3 % (n=5) and P53mn in 85,7 % (n=6) of rCBV<=2,7 patients group. CONCLUSION MRI DSC-T2* studies obtained three months after QT&RT finalization in GBM patients appears to showed prognostic value and correlation with unfavourable expressions of EGFR and P53 mutation. Keywords GBM (Glioblastoma Multiforme), MRI DSC-T2* cerebral perfusion, EGFR, P53 mutation P.1.004 A N E U RY S M A L B O N E C Y S T O F S P H E N O I D B O N E AND CLIVUS MISDIAGNOSED AS CHORDOMA: A CASE REPORT F. Ustabasioglu, I. Yanik, E. Huseynov, M. Asik, Z.I. Hasiloglu Istanbul University Cerrahpasa Medical Faculty, Department of Radiology, Istanbul, Turkey PURPOSE Aneurysmal bone cysts (ABC) are benign bone tumors that most commonly occur in people younger than 30 years. The cysts are most often found in the metaphyses of long bones. The involvement of skull base, particularly clivus is an uncommon location for ABC. It is an expansile, multi-loculated destructive bone lesion. Herein, we present the magnetic resonance (MR) imaging features of a sphenoid bone and clivus ABC misdiagnosed as skull base chordoma. METHOD A 21-year-old male who had undergone a resection of a mass in the skull base which was misdiagnosed as chordoma in a different hospital’s surgery department. Because of pathologic discrepancy the preoperative cranial MR images were consulted to our radiology department. RESULT In the pre-operative cranial MR imaging, expansile clival and sphenoidal lesion was seen as lobulated, well-demarcated, and multiloculated fluid-fluid cavities. MR images showed

S79 heterogeneous intensities on T1-weighted and T2-weighted images. Also T2-weighted images revealed surrounding hypointense sclerosis. There was heterogeneous enhancement on contrast enhanced T1-weighted images. ABC was histologically identified as we predicted. CONCLUSION Skull base involvement of ABC is extremely rare. In our case ABC was under-recognized and misdiagnosed as chordoma. Radiologic awareness of skull base ABC is lacking and patients with this disease may undergo unnecessary extended surgery. Keywords Aneurysmal bone cyst, chordoma, skull base P.1.005 DIFFERENTIATION OF PRIMARY AND SECONDARY BRAIN TUMOURS USING DYNAMIC SUSCEPTIBILITY CONTRAST MRI PERFUSION A. Sprlakova-Pukova1, M. Kerkovsky1, J. Stulik1, R. Jirik2, O. Macicek2, K. Bartusek2 1

The University Hospital Brno and Masaryk University, Department of Radiology, Brno, Czech Republic, 2Brno University of Technology, Department of Biomedical Engineering, Brno, Czech Republic PURPOSE This work represents an early part of a project aimed at the computational analysis of the MR perfusion data using advanced segmentation methods. At this initial stage we performed a small-sample analysis of the dynamic susceptibility contrast (DSC) perfusion using conventional region of interest (ROI)-based approach. We tried to apply the findings of the previous studies focused at the discrimination of a primary and secondary brain tumors using DSC perfusion at the routine clinical setting. METHODS The study group included 12 patients with brain tumors, all of them were examined at 1,5 T MR device including DSC perfusion imaging. The total of 13 lesions was analyzed (6 high-grade gliomas and 7 metastases). From the perfusion data we measured the cerebral blood volume (CBV) values using 12 different ROIs for each lesion, six of them placed within the enhancing mass of the tumor, another six within the peritumoral edema. We calculated the variability of the measured values and compared the average, minimal and maximal CBV values between the subgroups of patients with glioma and metastases. RESULTS We found no statistically significant difference of the CBV values between the glioma and metastases subgroups of patients. The variation coefficients of the CBV values measured at different ROIs at the enhancing part of the tumors and peritumoral edema were 36,4 % (range 17,5-57,3 %) and 35 % (range 11,5-64,3 %) respectively. CONCLUSION In our small sample of patients we were not able to reliably differentiate between the gliomas and metastases based on the ROI analysis of DSC perfusion data. Furthermore, the perfusion of the tumors and surrounding tissue seems to be rather inhomogenous, which makes the evaluation using ROI analysis of the perfusion data at the individual level fairly unreliable. More advanced techniques like histogram analysis or pattern recognition may be useful. Supported by GACR P102/12/1104 Keywords Perfusion, brain tumours, magnetic rezonance imaging

S80 P.1.006 IDENTIFICATION OT TREATMENT VOLUMES FOR RADIOTHERAPY PLANNING OF THE INTRA-AXIAL BRAIN TUMORS USING CT AND MR IMAGES FUSION L. Sibilla1, G.B. Ivaldi2, S. Montagna1, P. Tabarelli3, M. Liotta3, L. Moro3, M. Baldi1 1

Research Institute S. Maugeri Found - Radiology Dpt., Pavia, Italy, Research Institute S. Maugeri Found - Radiotherapy Dpt., Pavia, Italy, 3 Research Institute S. Maugeri Found - Medical Physics Service, Pavia, Italy 2

PURPOSE To determine if magnetic resonance images (MRI) are particularly helpful in providing accurate definition of the target for radiotherapy of brain tumours. The techniques of image fusion are powerful field of diagnostic imaging to combine and integrate different information summing the various diagnostic potential of each individual technique. In brain radiotherapy a computed tomography (CT) must be performed because it contains the necessary electron density information required for dosimetric calculations in the treatment planning. On the other hand MRI improves soft tissue contrast and may offer an advantage to identify target volume. In S. Maugeri Foundation a multimodality imaging protocol has been applied to define the target volume in brain tumours. METHODS A custom-molded thermoplastic masks was used for about 20 patients treated for intra-axial brain tumors. Images for treatment planning are acquired on both a multislice CT scanner (MSCT, GE Light Speed RT16) and a 1.0 Tesla MR scanner (Simens Magnetom Harmony. MRI was acquired with a flash 3D-VIBE, isotropic, 1 slab (176 slices), thickness 1 mm, TR 7.71, TE 3.77, FA 12, matrix 256*256, FOV 230. The patient is positioned in the magnet with the masks and we use spine array coil, back, and body extender coil in front. The CT and MR datasets are then transferred to treatment planning system (TPS) Pinnacle version 9.0 (Philips Medical System). MR id co-registered with CT, first by a manual adjustment and then automatically applying a rigid body transformation through the mutual information algorithm which measures the statistical dependence between the image intensities of corresponding voxels in both images. RESULTS The physicist performs a visual check of the adequacy of the anatomy landmark registration on axial, sagittal and coronal planes. Finally the radiation oncologist with the aim of the neuroradiologist contours the target volume on the MR images and this volume is automatically associate with the CT scans where the treatment planning is studied. CONCLUSIONS We find that the volumetric MRI has proved to be crucial in order to obtain accurate definition of the target, allowing the use of modern intensity modulated radiotherapy techniques with high spatial dose gradient. Keywords Brain tumors, radiotherapy, 1 T-MRI P.1.007 ORBITAL CAVERNOUS HEMANGIOMA: DIAGNOSIS WITH CT-PERFUSION I. Schurova, I. Pronin, V. Kornienko Burdenko Neurosurgery Institute, Moscow, Russia

Neuroradiology (2013) 55 (Suppl 1):S15–S159 INTRODUCTION Orbital cavernous hemangioma (OCH) is a benign, noninfiltrative, slowly progressive vascular neoplasm that develops as a result of abnormal vascular system. The tumor occurs in 70 % of patients with vascular lesions of the orbit, so it is important to diagnose it at the preoperative level. MATERIAL AND METHOD CT perfusion were performed in 14 patients with OCH on multislice CT scanners “Brillance,” (Philips) and “Highlight” (GE): CT perfusion at the orbital level included 4 slices with thickness 5 mm (100 mA, 80 kV), (160 images), acquisition time – 40 s, radiation dose −1,8 mSv. All patients underwent MRI (standart T1,T2, T1+Gd; FAT SAT before and after Gd and CT before and after surgical treatment. Pathomorphological verification was carried out in all patients. Cerebral blood flow, (CBF), cerebral blood volume (CBV) and mean transit time (MTT) maps were calculated. RESULTS OCH had completely different MRI and CT features, including contrast enhancement. But CT perfusion parameters were similar: CBVand CBF in all 14 patients decreased in comparison to the brain white matter and averaged 1, 2 ml/100 mg for CBV and 12 ml/100 mg/min – CBF. MTT in OCH is prolonged and the average time is 8 s. Based on these results a graph is made (1). CONCLUSION CT-perfusion is an effective method in diagnosis cavernous hemangioma which allows to assess tumors hemodynamic, its vascularization and to make more specific differential diagnosis. It may help to decrease the number of patients undergoing preoperative biopsy and to plan optimal surgical approach. Keywords Orbit tumors, orbit cavernous hemangioma, CT-perfusion P.1.008 3D-TSE-T1W:A MATTER OF SENSITIVITY I. Saralegui1, I. Vicente1, J.M. Ontañón1, J. Sanchez2, A. Cabrera1 Galdakao Hospital, OSATEK, Usansolo, Spain, 2 MR Clinical Department, Philips Healthcare Iberia, Madrid, Spain 1

PURPOSE To compare the accuracy between T1-weighted 3D and axial T1weighted 2D spin-echo postcontrast sequences in the detection and characterization of brain pathology. METHODS Prospective study including 79 lesions in 76 patients with diverse brain pathology. The examinations were performed in a Philips 3.0 T-TX Achieva system with a 32-channel head coil (Philips Healthcare). The precontrast examinations included T1-weighted 3D; axial TSE-T2, FLAIR and diffusion-weighted; and coronal TSE-T2 sequences. A bolus of 0,1 mmol/kg of gadopentetate dimeglumine was administered in every patient. The postcontrast examinations included a 3D-TSE-T1W using flip angle sweep readout strategy (TR/TE 500/34 msec; SENSE 2.2; flip angle, 90°; matrix size, 252 x 249; field of view, 250 x 250; number of slices, 360; in plane resolution 1 x 1 x 0.5 mm; NSA 2), total acquisition time 4´53”; and an axial T1-weighted 2D spin-echo sequence (T1-SE2D) (TR/TE 500/10 msec; flip angle, 70°; matrix size, 252 x 249; field of view, 232 x 182; 3 mm thickness with no gap; number of slices, 40; NSA 1), total acquisition time 4´48”. RESULTS Two cases corresponded to inflamatory processes with similar findings in both sequences.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 In all cases with vascular pathology (1 AVM and 6 venous angiomas) the T1-SE-2D was superior to the 3D-TSE-T1W sequence. In one case of tuberculous meningitis 3D-TSE-T1W defined better meningeal involvement. 19 extra-axial tumors were included: 1 pinealoma, 1 subependymoma, 1 papilloma, 3 neurinomas and 13 meningiomas. All tumors were depicted equally or better in 3D-TSE-T1W (18 cases). 21 patients were studied for metastatic disease screening. 3D-TSE-T1W accuracy was similar or greater in the 10 patients affected. 22 intra-axial tumors were evaluated (19 gliomas, 2 oligodendrogliomas, 1 ependymoma, and 1 case of multiple hemangioblastomas). The 8 cases where T1-SE-2D was superior to 3D-TSE-T1W correponded to surgically treated tumors. CONCLUSIONS T1-weighted 3DW sequence is a useful tool in clinical practice to evaluate intracranial tumoral pathology. In our experience 3D-TSE-T1W sequence categorizes brain tumoral pathology properly and allows multiplanar reconstructions with a similar acquisition time than T1-SE-2D sequence. Nevertheless ís less accurate evaluating postsurgical changes and it can´t be used in the evaluation of vascular lesions. Keywords Tumors, gadolinium, brain P.1.009 MRI BLOOD POOL CONTRAST AGENTS: IMPROVED IMAGING OF GLIOBLASTOMA J. Puig1, G. Blasco1, W. Chwang2, J. Daunis-I-Estadella3, M. Essig4, R. Jain2, S. Pedraza1

S81 longer window for data acquisition. Gadofosveset provides strong, persistent intravascular enhancement that can be exploited to acquire additional high-resolution images, enabling better delineation of neovessels. The ability of MRI techniques using BPCA to reveal changes in tumor microvascularity is likely to accelerate the development, testing, and monitoring of new antiangiogenic drugs. Additionally, BPCA make it possible to reduce the dose of contrast compared to extracellular gadolinium agents (0.03 mmol/kg vs 0.1-0.3 mmol/kg) without diminishing scan quality. SUMMARY The future of BPCA imaging is promising. This exhibit shows the usefulness of gadofosveset in the diagnostic workup of glioblastoma. It discusses the potential role of BPCA as a reliable noninvasive imaging technique for the assessment and monitoring of angiogenesis. Keywords Brain neoplasms, magnetic resonance imaging, contrast media P.1.010 VALUE OF DIFFUSION TENSOR IMAGING IN DIFFERENTIATING HIGH-GRADE FROM LOW-GRADE GLIOMAS S. Piyapittayanan1, O. Chawalparit1, S. Tritakarn1, T. Witthiwej2, T. Sangruchi3, S. Nanta-Aree2, S. Sathornsumetee4, P. Itthimethin2, C. Komoltri5 1

Siriraj Hospital, Department of Radiology, Bangkok, Siriraj Hospital, Department of Surgery, Bangkok, 3 Siriraj Hospital, Department of Pathology, Bangkok, 4 Siriraj Hospital, Department of Medicine, Bangkok, 5 Siriraj Hospital, Department of Research Development, Thailand 2

Thailand, Thailand, Thailand, Thailand, Bangkok,

1

Department of Radiology (IDI), Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain, 2Division of Neuroradiology, Department of Radiology, Henry Ford Health System, Detroit, MI, USA, 3Department of Computer Science, Applied Mathematics and Statistics, University of Girona, Girona, Spain, 4Diagnostic Radiology and Neuroradiology, Department of Neuroradiology, University of Erlangen, Erlangen, Germany PURPOSE Contrast-enhanced MRI is the modality of choice for evaluating brain tumors. Gadolinium-based agents are the most commonly used contrast agents in clinical MRI. We describe the usefulness of the proteinbinding blood pool contrast agent (BPCA) gadofosveset in de novo glioblastoma and highlight its potential for improving the diagnostic quality of contrast-enhanced MRI in brain tumors. APPROACH/METHODS 1. We explain the mechanism of action of BPCA, with particular emphasis on protein targeting and increased T1 relaxivity. 2. We explain how to optimize the use of BPCA for imaging tumors. 3. We use cases from our research on glioblastomas to illustrate the spectrum of tumor enhancement and findings on tumor steady-state MR angiograms obtained with BPCA (Olea Medical, Sphere, La Ciotat, France). 4. We discuss the potential of BPCA as a surrogate marker of tumor angiogenesis. FINDINGS/DISCUSSION BPCA represent a new class of contrast agents for tumor imaging. Gadofosveset binds strongly but reversibly to albumin in plasma, resulting in four to five times higher relaxivity, better vascular retention, and thus longer intravascular half-life (~16 hours vs ~90 min) than extracellular contrast agents. These characteristics result in increased tumor enhancement, enabling better diagnostic information for highgrade glioma (more accurate delineation of tumor margins and extension that allow better planning for resection and radiotherapy) and a

OBJECTIVE To determine the usefulness of diffusion tensor imaging (DTI) in differentiating high grade glioma (HGG) from low grade glioma (LGG). MATERIAL AND METHOD Patients with cerebral gliomas underwent conventional MRI and DTI before surgery. All proven pathology were classified into two groups, i.e. LGG and HGG. We measured fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values in region of interest (ROI) including solid tumoral region, necrotic region, peritumoral edema, contralateral normal appearing white matter (NAWM) and normal corpus callosum as well as calculated ADC ratios. Pairwise comparisons were performed by using the t-test. The ROC curves of imaging parameters were employed to determine the best parameter for differentiating the two entities. RESULTS Forty three patients with cerebral gliomas, 17 with LGG and 26 with HGG, no statistical significant difference between LGG and HGG using mean FA values in each ROI. The ADC and minimal ADC values of solid tumoral region and peritumoral edema, the ADC and minimal ADC ratios of solid tumoral region are statistical significant to differentiate HGG from LGG, P<0.05. The ratio ADC solid tumoral region to normal corpus callosum had highest predictive accuracy to differentiate the two entities with AUC of 0.74. CONCLUSION The ADC value, minimal ADC value, and ADC ratios of solid tumoral region appeared to be useful for differentiating HGG from LGG. Keywords Brain tumor, glioma, DTI P.1.011 METASTATIC MELANOMA FOR DUMMIES J. Nair1, C.I. Torres1, J. Chankowsky1, R. Del Carpio O'Donovan1, J. Beegom Mansoor2

S82 1 Department of Radiology, Montreal General Hospital, Mcgill University, Montreal, Canada, 2Baraha Hospital, Ministry of Health, Dubai, United Arab Emirates

PURPOSE Describe the Magnetic Resonance Imaging (MRI) findings, especially the signal intensity characteristics of metastatic melanoma based on its content. Identify the various patterns and sites of intra/ extra cranial involvement. To analyze the imaging characteristics and pattern following chemo/radiotherapy. METHODS 75 patients with melanoma were screened for metastasis of the head, neck and the cranio-spinal axis using standard MRI sequence including T1, T2, FLAIR ( Fluid Attenuated Inversion Recovery), DWI ( Diffusion Weighted Imaging), GRE (Gradient Echo) and Post-Contrast T1 sequences in Multiple Planes. 25 patients with metastatic melanoma to the brain, post-chemo and radiotherapy were also evaluated using the same standard MRI sequences. RESULTS Two basic imaging patterns, based on signal intensity characteristics were noted. The melanotic form were characterized by high signal intensity on T1-weighted images and low signal intensity on T2weighted images while amelanotic lesions appeared hypo intense or iso intense to the cortex on T1-weighted images and hyper intense or iso intense to the cortex on T2-weighted images. Melanoma having appearances different from the melanotic or amelanotic pattern were also noted. In addition to the brain, melanotic deposits were also noted in the internal auditory canals, meninges, muscles, nasopharynx, choroid plexus, spinal cord and spinal nerve roots. CONCLUSION Malignant melanomas have a wide spectrum of appearance and involvement of the intra and extra cranial structures. Although brain is the most common site of metastasis in the head and neck, metastatic melanoma can involve any structure intra/ extra cranially and also along the cranial-spinal axis This pictorial review from our institution will better familiarize radiologists with typical and atypical imaging features and locations of malignant melanoma on MRI when screening patients for metastatic melanomas. Keywords Melanoma, signal Intensity, magnetic resonance imaging P.1.012 FUNCTIONALNEUROIMAGINGTECHNIQUESINTHEEVALUATION OF CENTRAL NERVOUS SYSTEM TUMORS: A MULTIMODALITY AND COMPREHENSIVE APPROACH J. Martinez Barbero1, T. Martín Noguerol1, M. Navarro-Pelayo Láinez2, M. Gómez Río2, J. Pastor Rull3 1

Clinica Las Nieves, Neuroimaging Department, Grupo HealthTime, Jaén, Spain, 2Hospital Universitario Virgen de las Nieves, Servicio de Medicina Nuclear, Granada, Spain, 3Hospital Universitario Virgen de las Nieves, Servicio de Radiología, Sección de Neuroimagen, Granada, Spain Nowadays, monitoring of primary CNS tumors treated, either with surgery, chemotherapy (with or without inhibitors of angiogenesis) or radiotherapy (cranial, fractionated or stereotactic) has become an extremely complex problem. Many imaging and pathological phenomena such as radionecrosis, pseudoprogresión or pseudoresponse must be taken into consideration, and differentiated from real response or

Neuroradiology (2013) 55 (Suppl 1):S15–S159 recurrence, and have shown the limitations of the Macdonald Criteria with the use of novel treatments. Radionecrosis is the main differential diagnosis of recurrence in CNS tumors treated with radiotherapy, and happens from 5 to 24 % of cases, according to different series. It is based on radiation induced damage especially to the vascular endothelium, that conditions contrast extravasation and inflammatory deposit with gliosis. Pseudoprogression is currently one of the main problems in the monitoring of CNS tumors treated with radiotherapy and chemotherapy, especially those under treatment with Temodal. It has been observed that during treatment (up to 3 months after completion) these lesions experience an increase in size and uptake contrast, ending when treatment stops. Pseudoresponse is a phenomenon secondary to the treatment with antiangiogenic agents, and must be differentiated from real response. In this poster, we will review current concepts in neuro-oncology follow-up, and we will make an extensive and comprehensive review of the current neuroimaging advanced techniques. A systematic review of the usefulness of diffusion-weighted imaging, Perfusion- MRI (Dynamic contrast enhancement), and Spectroscopy, as well as Nuclear Medicine imaging techniques commonly used in brain tumor follow up, such as PETCT and SPECT with Thallium or Methionine will be made, including many clinical and practical examples. Keywords Multimodality, brain tumors follow up, advanced functional imaging P.1.013 INTRACRANIAL METASTATIC MELANOMA: DIAGNOSIS, IMAGING AND TREATMENT C. Mandel Peter MacCallum Cancer Centre, Cancer Imaging, Melbourne, Australia PURPOSE Melanoma is one of the commoner malignancies in young adults. In countries where a sun-safety culture is less developed, melanoma often presents with metastases which may be intracranial. The imaging appearances are diverse which may lead to diagnostic error. Understanding the imaging appearances is essential for accurate diagnosis and good management of these patients. This paper will illustrate the range of appearances of intracranial metastatic melanoma, discuss the diagnostic pitfalls and provide an update on treatment of intracranial disease. METHODS Our patients' images were reviewed in order to illustrate the diverse range of appearances of intracranial metastatic melanoma. The cause of these appearances discussed. The current treatment options, and the radiological features that influence the choice of treatment will be described. RESULTS There is a wide variety of appearances of intracranial metastatic melanoma. Whilst the classical appearance of melanoma is high signal intensity on T1-weighted images, the 'melanotic pattern', melanoma is more often iso- or low intensity. Haemorrhagic changes are common and are another cause increased signal on T1W imaging. Metastases may range in size from miliary to very large with significant mass effect requirng urgent neurosurgery. Melanoma may metastasise to any intracranial structure, including the choroid plexus, the ependyma, the meninges, and the cranial nerves. lesions in these locations wil be demonstrated.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Treatment options include, neurosurgery, stereotactic and whole brain radiotherapy, chemotherapy, kinase (BRAF) inibitors or a combination of these. CONCLUSIONS Intracranial melanoma has a wide range of imaging appearances. Accurate interpretation of neuroimaging is essential as new treatments that are effective in controlling metastatic melanoma. The size, location and number of lesions is important in determining eligibility for neurosurgery and radiotherapy. Keywords Metastatic melanoma, intracranial metastases, magnetic resonance imaging P.1.014 INTRACRANICAL HEMANGIOPERICYTOMA: CASE REPORT AND REVIEW OF LITERATURE C. Gagliardo, S. Regalbuto, C. Sarno, F. Cannizzaro, G. La Tona, M. Midiri DI.BI.MEF., Radiology Section, University of Palermo, Palermo, Italy PURPOSE We present a case of intracranical hemangiopericytoma (HPC) in a patient with migraine (male, 49 years old), who also presented mental confusion and partial left sensorimotor syndrome. We will also provide some elements regarding the international classification of this rare and highly vascularized mesenchymal tumor, and will consider possible differential diagnosis with other more common extra-axial masses. METHODS After a preliminary examination in ER, patient underwent to head CT examination and was then transferred to the neurosurgical unit. The day after a brain MR examination was performed using advanced techniques too (PWI, and MRS); before surgery also functional MR imaging (fMRI) and CTA where performed. RESULTS CT scans showed a left frontoparietal expansive lesion, most likely of extra-axial nature, with heterogeneous characteristics and polilobulated margins. There was a severe mass effect on adjacent parenchymal structures and heavy involvement on the adjacent skull bone. MR examination with conventional sequences confirmed the extra-axial nature of the lesion, which appeared to be highly vascularized as later confirmed by CTA. The analysis of lesions perfusion by DSCE-PWI (EPI-T2*w) confirmed these findings, showing permeability curves compatible with a highly vascularized lesion (high rCBV and rCBF values) without hematoencephalic barrier. Spectroscopy examination showed an increased Cho peak, compatible with a high cell proliferation with a lipid/lactate peak into the intralesional areas of necrosis. Diagnostic hypothesis of HPC was placed. The fMRI presurgical examination allowed to identify language and motor areas that were all considerably dislocated. CONCLUSIONS Pathologic examination confirmed diagnosis of anaplastic HPC (WHO III), a tumor originating from malignant transformation of microcircle Zimmerman’s pericytes, a rare tumor of the central nervous system (0,4 % of all primary tumors, previously classified as angioblastic meningioma). Anaplastic HPS (AHPC) is usually characterized by a more lobulated shape, substantial bleeding, necrosis or cystic areas, marked peritumoral edema and signs of cranial table erosion, while the typical “dural tail” sign is more frequent in the non-anaplastic types (WHO II). Keywords Hemangiopericytoma, CT and MR imaging, differential diagnosis

S83 P.1.015 DIAGNOSTIC PERFORMANCE OF ADVANCED MRI IN DIFFERENTIATING HIGH-GRADE FROM LOW-GRADE GLIOMAS IN A SETTING OF ROUTINE SERVICE O. Chawalparit1, T. Sangruchi2, T. Witthiwej3, S. Sathornsumetee4, S. Tritrakarn1, S. Piyapittayanan1, P. Chaicharoen1, T. Direksunthorn1, P. Charnchaowanish1 1 Department of Radiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, 2Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, 3Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, 4Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand

OBJECTIVE To evaluate the usefulness of advanced MRI techniques in differentiating high-grade (HGG) from low-grade gliomas (LGG). METHODS 64 patients with suspected gliomas were prospectively evaluated by conventional and advanced MRI studies including MR spectroscopy (MRS), diffusion tensor imagining (DTI) and dynamic susceptibility contrast (DSC) MRI. The parametric measurements of metabolic profile, cerebral blood volume, flow (CBV, CBF), apparent diffusion coefficient (ADC), fractional anisotropy and their ratios by internal normalization were analyzed for differentiating LGG from HGG. Histopathologic findings were used as the gold standard. RESULTS 43 cases with pathologically-proven gliomas were included. The best discriminating features between HGG and LGG were CBV and CBF of the solid tumoral region (p < 0.05); whereas the minADC/corpus callosum ratio for DTI and the ratio of Cho/Cr for MRS of the solid tumoral region provided the best diagnostic performance (p<0.05). With a predetermined threshold for each parametric measurement, the combination of all advanced MRI modalities was associated with the best accuracy; whereas the combination of DSC MRI and MRS provided the highest specificity. When all parametric measurements were positive, the probability of HGG was 0.889. CONCLUSION Comprehensive advanced MRI studies provided better diagnostic performance than using conventional MRI alone in the evaluation of gliomas. Keywords Gliomas, MRI, advanced P.1.016 AMIDE PROTON TRANSFER IMAGING: IS SINGLE REPRESENTATIVE SLICE ANALYSIS SUFFICIENT FOR TUMOR GRADING? S. Akihiko1, T. Okada1, A. Yamamoto1, M. Kanagaki1, Y. Fushimi1, E. Morimoto1, R. Sakamoto1, T.H. Mehemed1, S. Nakajima1, S. Okuchi1, T. Kakigi1, T. Dodo1, B. Schmitt2, K. Murata3, K. Togashi1 1

Department of Diagnostic Imaging and Nuclear Medicine, Kyoto Universty, Kyoto, Japan, 2Siemens AG, Munich, Germany, 3Siemens Japan, Tokyo, Japan PURPOSE Amide proton transfer (APT) MR imaging is a kind of chemical exchange saturation transfer imaging to detect amide protons. Many of the previous studies employed single slice (2D) acquisition due to technical

S84 limitations, but if analysis of a representative 2D slice is sufficient or not has not been investigated. The purpose of this study is to compare diagnostic performance of three-dimensional (3D) APT imaging that covers the entire tumor and a single representative slice to differentiate low-grade glioma (LGG) and high-grade glioma (HGG). METHODS This study is approved by institutional review board. Thirty-two patients of histologically-proven glial tumors were included (LGG 8 and HGG 24 patients) and scanned with a 3 T MRI using a 3D gradient-echo pulse sequence (TR/TE=8.3/3.3 ms, Flip angle: 12°, 24 slices, resolution: 1.72×1.72×4 mm) with a pre-saturation module consisting of five RF pulses with 99 ms duration plus 1 ms delay and 1.6μT amplitude. APT asymmetry was calculated as a percentage difference in magnetization transfer rate at ±3.5 ppm: APTasym=(S[+3.5 ppm] - S[−3.5 ppm])/S0×100 %. APTasym images were co-registered to FLAIR images and re-sliced using SPM8. For each subject, a ROI was placed on a single representative slice of the tumor and whole tumor slices, and the APTasym values were compared between high and low tumor grades using t-tests and ROC analysis. RESULTS The averages±SD of LGG were 1.17±0.36 and 1.14±0.31 for 2D and 3D imaging, respectively. Those of HGG were 1.95 ± 0.71 and 1.88±0.67, respectively. Both 2D and 3D imaging had significant difference between LGG and HGG (P=0.0064 and 0.0003, respectively). The ROC analysis showed no statistically significant difference in differential diagnostic capability between the two imaging conditions (P=0.68). CONCLUSIONS The APT imaging of a representative slice could differentiate between LGG and HGG. No significant difference was observed between 2D and 3D imaging. This result will help to facilitate usage of APT imaging within a reasonable scan time of 2D acquisition. Keywords Amide proton transfer, glioma, grading P.1.017 A CASE REPORT OF GLIOSARCOMA: CT AND MRI FINDINGS K. Suzuki1, M. Hori2, H. Suzuki1, M. Kobayashi1, J. Kodera1, Y. Okada1, S. Mizumura1, N. Shiraga1, H. Terada3, T. Nagao3, T. Kuroki3, W. Tokuyama3, H. Hiruta3, E. Kohta4 1 Toho University Omori Medical Center, Tokyo, Japan, 2Juntendou University, Tokyo, Japan, 3Toho University Sakura Medical Center, Chiba, Japan 4Toho University School of Medicine, Tokyo, Japan

PURPOSE Gliosarcoma is a rare malignant central nervous system tumor with mixed glial and mesenchymal components.We report a case of gliosarcoma with computed tomography (CT) and magnetic resonance imaging (MRI) findings. METHODS Case report A 72 year-old female with headache. She had a history of breast cancer. An tntra-axal tumor was diagnosed by CT and MRI. She had a craniotomy, and the tumor was diagnosed gliosarcoma pathologically. She received radiotheraphy, and chemotherapy, after surgical resection. RESULTS AND CONCLUSIONS Imaging Findings Well-demarcated tumor with hemorrhage was found in the right temporal lobe. Hypodense tumor with surrounding edema and intra-tumoral hyperdence area related to hemorrhage on non-enhanced CT. Thick irregular ring enhancement surrounding tumor was seen on contrast enhanced CT. The tumor is hypointense on T1-weighted images (T1WI) and heterogeneous hyperintense and hypointense area related to hemorrhage on T2-weighted (T2WI) images, and ring enhancement was seen on

Neuroradiology (2013) 55 (Suppl 1):S15–S159 contrast enhanced T1WI. The tumor abut dural surface, with continuous dural enhancement. No systemic metastasis was found. SUMMARY We report a case of gliosarcoma. Imaging findings were so similar to those of an glioblastoma that it was difficult to distinguish gliosarcoma from a glioblastoma. However, if the tumor has aggressive invasion of dura,gliosarcoma should be included in the differential diagnosis. Keywords Gliosarcoma, brain tumor, MRI

Head and neck imaging P.1.018 ADULT PAROTID TUMORS: A RADIOPATHOLOGIC CORRELATION D. T. Wang1, L. Wang2, A. Bahel2, I. Bhutani3, R. Cornelius2 1

Dpt. of Radiology, Royal Melbourne Hospital, Melbourne, Australia, University of Cincinnati, HospitalMedical Center, Cincinnati, OH, USA, 3 Dpt. of Pathology, University of Cincinnati Medical Center, Cincinnati, OH, USA 2

PURPOSE The parotid glad is the largest salivary gland. These tumors are not uncommon. This poster will review malignant and benign adult parotid tumors correlating with gross and histologic pathology. METHODS Review of the head and neck oncology pathology database and radiology records at a major head and neck multidisplinary referral center for the past 10 years for spectrum and examples of parotid tumors. RESULTS Imaging findings of benign and malignant, common and uncommon parotid gland tumors will be reviewed with pathological correlation. Primary tumors such as pleomorphic adenoma, Warthin tumor, salivary duct carcinoma, sarcomatoid carcinoma, squamous cell carcinoma, mucoepidermoid carcinoma, adenoid cystic carcinoma, lymphoma and intra-parotid metastasis from skin malignancy. Common routes of spread will be reviewed. CONCLUSION Although distinguishing different types of parotid tumors by imaging alone is difficult, radiological identification of parotid tumors can assist in the management and treatment of patients. Keywords Parotid tumors, metastases, pathology P.1.019 ALGORITHMIC APPROACH TO CYSTIC LESIONS OF THEPAROTID GLAND AND THEIR MIMICS E. Ryan, M. Mccusker, M. Thornton, A. O'Hare, P. Brennan, S. Looby Department of Neuroradiology, Beaumont Hospital, Dublin, Ireland PURPOSE Many cystic parotid lesions present with a palpable mass, with or without pain, and cytological diagnosis can be non-diagnostic, or indeed not required if imaging is definitive. Accurate imaging is an important adjunct to cytological evaluation to determine the lesions that may benefit from surgical management versus socalled 'leave-alone' lesions. This has important implications for patients in terms of early management of invasive lesions, and avoiding potential surgical morbidity for those lesions with a benign aetiology.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS Using a PACS archive, patients with cystic parotid masses were retrospectively recruited. Correlation was made with cytological analysis or histopathology of resected specimens where appropriate. Imaging characteristics on non-enhanced and enhanced computed tomography and on multi-planar multi-sequence magnetic resonance imaging were recorded and compared. RESULTS Cystic masses of the parotid gland range from benign lesions such as Warthin's tumour, benign cysts, lymphoepithelial cysts, mucous retention cysts, cystadenomas, cystic pleomorphic adenomas to malignancies such as mucoepidermoid carcinoma and cystadenocarcinoma. We demonstrate an algorithm for the differential diagnosis of cystic parotid gland masses. CONCLUSION Cystic parotid masses represent an important diagnostic challenge in head and neck imaging. An algorithmic approach to the differential diagnosis of such lesions is proposed. This may assist in identification of benign lesions and selection of cases for surgical resection, with important implications for morbidity and quality of life. Keywords Cystic parotid lesion P.1.020 THE VERTEBRAL ARTERY - ORIGIN, EXTRACRANIAL COURSE, VARIATIONS AND ASSOCIATION WITH VASCULAR DISEASES DIAGNOSED BY CTA M. Tysiac1, F. Brassel2, A. Berenstein3, D. Meila2,4 1

Klinikum Duisburg, Sana Kliniken, Department of Anaesthesiology, Duisburg, Germany, 2Klinikum Duisburg, Sana Kliniken, Department of Radiology and Neuroradiology, Duisburg, Germany, 3Roosevelt Hospital, Center for Endovascular Surgery, New York, NY, USA, 4Hannover Medical School, Department of Diagnostic and Interventional Neuroradiology, Hannover, Germany PURPOSE The aim of this study was to show the different origins and extracranial courses of the VA. The duplicated VA is an anomaly that has been assumed to predispose for dissection and to be associated with aneurysms. We report its frequency and clinical significance. METHODS We retrospectively reviewed CTA of 539 patients from 2007 to 2012. RESULTS 94.2 % of left VA originated from left subclavian artery and entered the transverse foramen at C6 in nearly all cases. 6.3 % of left VA (m=4 %, f=10 %) originated from the aortic arch and entered the transverse foramen either at C4, C5 or C7 but never at C6. One case of an aberrant retroesophageal right VA originated from the aortic arch distal to the left subclavian artery and entered at C7 (0.19 %). All other right VA originated from the right subclavian artery (99.8 %) and entered between C4 and C6. We diagnosed 4 cases of duplicated VA (0.74 %) with a female predominance (1.9 %) without any signs of dissection on CTA. Two cases with VA duplication had intracranial arterial aneurysms. CONCLUSIONS The VA is a longitudinal anastomosis of segmental metameric arteries. The level of entrance into the transverse foramen indicates which metameric artery or arteries persist. Duplication corresponds to persistence of two segmental arteries and is a rare phenomenon. VA duplication might be associated with vascular lesions. Keywords Vertebral artery, CTA, anatomy

S85 P.1.021 ANATOMICAL AND PATHOLOGICAL MRI ATLAS OF UPPER THORACIC OUTLET. A NEW APPROACH TO AN OLD CHALLENGE J. Martinez Barbero, T. Martín Noguerol Clinica Las Nieves, Sercosa, Grupo Health-Time, Jaen, Spain POURPOSE/AIM 1. To review the optimal sequences and MRI techniques used for the study of upper thoracic outlet anatomy. 2. Detail the anatomic structures involved in this transit region between neck and thorax in a MRI-based atlas. To describe the normal anatomy, variants of normality and pathology of UTO. 3. Show the advantage of MRI for assessing the main pathological processes that involved this anatomical area. To illustrate the importance and advantages magnetic resonance imaging reconstructions and functional techniques for the evaluation of anatomy and pathology of UTO. CONTENT ORGANIZATION - To Review the most appropriated sequences for the evaluation of this area: morphological, MRA 3D and 4D, HASTE and functional techniques such diffusion weighted imaging (DWI), diffusion tensor imaging (DTI) and perfusion weighted imaging (PWI). - To Perform a MRI-based atlas of upper thoracic outlet highlighting the anatomy of this region: peripheral nerves, vascular and lymphatic drainage systems, bone structuresand soft tissues including upper airway, esophagus and lung apices. - To Illustrate the clinical applications and main pathological conditions that take place in this controversial anatomic area. SUMMARY The thoracic outlet is a challenge anatomical region. This transitional area has been classically considered a clash zone between head and neck and thoracic radiologists. The major teaching points of this exhibit are: -To get familiar with the anatomy and pathology trough an MRI anatomical and functional approach - To Demonstrate the advantages of the functional advanced MRI sequences for the assessment of pathology in this region. Keywords Head and neck, thoracic outlet, advanced MRI sequences P.1.022 THE VALUE OF MR IMAGING FOR THE DIAGNOSIS OF OPTIC NERVE NEUROPATHY IN PATIENTS WITH GRAVES’ DISEASE E. Maj 1 , A. Cieszanowski 1 , P. Miskiewicz 2 , K. Trautsolt 2 , T. Bednarczuk2, A. Samsel3, A. Krzeski4, O. Rowinski1 1 Medical University of Warsaw, 2nd Department of Clinical Radiology, Warsaw, Poland, 2Medical University of Warsaw, Chair and Department of Internal Medicine and Endocrinology, Warsaw, Poland, 3Medical University of Warsaw, Chair and Department of Ophthalmology, Warsaw, Poland, 4Medical University of Warsaw, Department of Otolaryngology, Warsaw, Poland

PURPOSE The most serious complication of thyroid ophthalmopathy is optic nerve neuropathy, which affects only 5 % of patients with Graves’ disease, but may lead to permanent visual loss. It is assumed that the cause is a mechanical compression of the optic nerve in the orbital apex by thickened oculomotor muscles. The aim of the study was retrospective evaluation of changes within the orbits by MRI in patients with clinical

S86 known neuropathy, qualified for immunomodulator therapy and surgery decompression. METHODS Analysis included 9 patients (8 women, 1 men) in whom, between July 2009 and December 2012, MR imaging was performed on 1.5 T system using following protocol: T1- and T2-weighted images with and without fat-saturation (axial plane), T1- and T2-weighted images with fat-saturation (coronal plane), T1weighted images (saggital plane). Evaluation included: apical crowding, effacement of the fat plane surrounding optic nerve, stretching of the optic nerve, anterior displacement of the lacrimal gland, prolaps of orbital fat through the superior ophthalmic fissure, proptosis and superior ophthalmic vein distention. RESULTS The most frequent abnormalities included: effacement of the fat plane surrounding optic nerve (in 8 of 9 patients) and apical crowding (in 6 patients). In 5 patients stretching and thinning of the optic nerve and anterior displacement of the lacrimal gland were observed and proptosis was noted in 4 patients. In none of the patients prolaps of orbital fat through the superior ophthalmic fissure or superior ophthalmic vein distention were demonstrated. CONCLUSIONS MR imaging may be useful for the identification of patients with the increased risk for optic nerve neuropathy in course of Graves’ ophthalmopathy. Keywords Graves disease, optic nerve neuropathy, MR imaging P.1.023 HYPERINTENSITY IN THE SUBARACHNOID S PA C E ON FLAIR MRI IN PATIENTS WITH RENAL INSUFFICIENCY: A DIAGNOSTIC PITFALL H. Kalkan, D. Kiresi Necmettin Erbakan University, Meram School of Medicine, Departmant of Radiology, Konya, Turkey Subarachnoid space (SAS) hyperintensity on fluid attenuated inversion recovery (FLAIR) images is an important finding that diferantial diagnosis must be done carefully. Because, FLAIR hyperintensity has lots of reasons: subarachnoid hemorrhage(SAH), leptomemingeal carsinomatosis, meningitis, etc.. Renal failure patients have comorbidities which they are performed many imaging methods for. One of the comorbidities are serebrovascular events and magnetic resonans imaging (MRI) is the best choice to diagnose them. But if patient was applied MRI with gadolinium before this, brain MRI will be confused because of delayed clearance and persistance of gadolinium on SAS, mimicking the serious pathologies above. PURPOSE We aimed to differantiate the SAS hperintensity on FLAIR images from pathologic conditions due to delayed clearance of gadolinium in renal failure patients. MATERIALS AND METHODS A 69 year old woman with chronic renal failure was performed neck MRI with gadolinium for neck pain and for vertigo the next day she underwent brain MRI without any contrast. The SAS were hyperintense on FLAIR images and this finding was suspicious of any other pathology, SAH, meningitis, etc.. But the patient had no meningeal irritation findings. The following day, for her persistant symptoms, brain MRI with gadolinium was performed. Precontrast images were similar with the images of yesterday. We considered that SAS hyperintensity was due to gadolinium that was used for neck MRI and which couldn’t eliminate, then excreted into CSF becuse of renal insufficiency. DISCUSSION Patients with renal failure had delayed clearance of gadolinium and metabolits. Gadolinium can’t excrete from urine, consequently it excretes to CSF. After IV gadolinium administration, CSF hyperintensity in the T1

Neuroradiology (2013) 55 (Suppl 1):S15–S159 weighted and FLAIR images is the result of delayed clearence of gadolinium. In our case there was no T1 weighted image hyperintensity in the SAS,ventricules. As a result IV gadolinium which was administered previously, may persist in the SAS and may lead to misdiaognose. Our patient was performed neck MRI with gadolinium the previous day. SAS hyperintensity because of gadolinium usage for any MRI of any body part, is a rare but important finding and difficult to consider if the radiolog doesn’t know patients’ renal failure history.So radiologist must investigate about patients’ comorbities. Keywords Renal insufficiency, subarachnoid space hyperintens, magnetic resonans imaging P.1.024 BRAIN MRI AND CT UTILIZATION TRENDS AMONG MEDICARE BENEFICIARIES: 2000–2007 R. Dhangana, P. Dhangana, M. Gupta, G. Muro Bridgeport Hospital, Yale New Haven Health, Department of Diagnostic Imaging, Bridgeport, CT, USA OBJECTIVE To study the trends of utilization of brain MRI and CT among Medicare beneficiaries from 2000 to 2007, and to determine payment amount for these services. MATERIALS AND METHODS We reviewed Medicare Part B Physician/Supplier Procedure Summary Master File (PSPSMF) for years of 2000, 2002, 2005, 2006 and 2007 and extracted claims for CT brain (CPT Codes 70450, 70460, 70470) and MRI brain (CPT codes 70551, 70552, 70553). Analyses were performed for total volume, trends of utilization, and total amount paid (professional component) by Medicare during a recent eight-year period. RESULTS Between 2000 and 2007, the total volume of brain CT utilization among Medicare population increased 1.5 fold, from 3.3 million to 5.1 million; whereas, brain MRI utilization increased 1.7 fold, from 1.1 million to 1.9 million. During the same interval, the total payment amount to providers for brain CTs increased by 1.4 fold, from $146.3 million to $206.8 million; and for brain MRIs increased 1.2 fold, from $279.7 million to $334.3 million. Of note, increased utilization of brain CT studies was primarily due to increased utilization of without contrast studies (CPT code 70450), increasing by 1.7 fold, from 2.8 million to 4.7 million (out of total 5.1 million CT heads performed in year 2007); whereas, MRI brain with and without contrast (CPT Code 70553) studies contributed most to increased MRI brain utilization, increased by 1.8 folds, from 0.65 million to 1.17 million. CONCLUSION There has been considerable growth in utilization of brain MRIs and CTs among Medicare beneficiaries between 2000 and 2007. In particular, brain MRI utilization has increased at a more rapid pace as compared to brain CT utilization rates between 2000 and 2007. Factors affecting these trends are of considerable interest. Keywords Brain CTs and MRIs, healthcare utilization, healthcare expenditure P.1.025 TRANSSPHENOIDAL MENINGOENCEPHALOCELE WITH NASAL FOSSA EXTENSION V. Cruz E Silva, J. Barreira, J. Graça, J. Ruivo, P. Soares Neuroradiology Department, Hospital Egas Moniz, CHLO, Lisbon, Portugal

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Spontaneous transsphenoidal meningoencephalocele is a rare entity, and even rarer through the Sternberg’s canal, which is a congenital defect on the lateral wall of the sphenoid sinus. To the best of our knowledge only 17 cases have been described in the literature and a smaller number from true transsphenoidal type. We report such a case in an obese 52-year-old woman with an 8-year history of spontaneous cerebrospinal fluid (CSF) rhinorrhea and recurrent meningitis. METHODS Brain Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) were performed, along with CT cisternography in which CSF opening pressure was measured. RESULTS CT scan showed a defect on the inferior and lateral wall of the right sphenoid sinus filled with a hypodense soft tissue mass connecting temporal fossa with sphenoid sinus and extending to the nasal cavity through the sphenoid ostium. MRI revealed herniated brain parenchyma from right temporal lobe surrounded by a meningeal sac through the sphenoid bone defect filling sphenoid sinus and protruding in the roof of the nasal fossa. Additionally an empty sella was seen. CT cisternography revealed iodide-contrast in the sphenoid sinus through the same bone defect, confirming the CSF leakage. CSF opening pressure was 270 mmH2O. CONCLUSIONS Meningoencephalocele should always be excluded in patients presenting spontaneous CSF fistula. MRI is the method of choice for the diagnosis, although bone defects are best depicted on CT scan. As in this case, meningoencephaloceles have been previously related to a benign intra-cranial hypertension in obese middle-aged women and occasionally to an empty sella. Keywords Meningoencephalocele, Sternberg's canal, CSF fistula P.1.026 SPONTANEOUS PNEUMOLABYRINTH AFTER VALSALVA MANEUVER SECONDARY TO PERILYMPHATIC FISTULA R. Carvalho1, J. Guimaraes2, J. Fernandes1, S. Vilarinho2, J. Rocha1 1

Neuroradiology Department, Hospital de Braga, Braga, Portugal, Otorinolaringology Department, Hospital de Braga, Braga, Portugal

2

PURPOSE Pneumlolabyrinth resulting from perilymphatic fistula is rare and it is usually diagnosed by high-resolution computed tomography (CT). It has been associated with barotrauma, iatrogenic injury, head trauma, and chronic ear disease; it can also develop spontaneously. Potential sites of gas entry include oval and round windows, microfissures between the posterior semicircular canal and the round window, and the fissula ante fenestram. METHODS Case-Report. RESULTS A 55-year-old male presented with acute onset of severe vertigo and right hearing loss, after blowing vigorously his nose. He had no history of head trauma, prior vertigo and ear disease. He had normal tympanic membranes bilaterally. The audiogram demonstrated right mixed hearing loss. The CT scan revealed air bubbles inside the external semicircular canal and the vestibule; and irregular air-fluid transition in the round window, suggesting pneumolabyrinth secondary to perilymphatic fistula. Exploratory timpanotomy confirmed perilymphatic fistula, as revealed air emanating from round window. It was repaired with tragal perichondrium, resulting in vertigo relief and audiometric improvement. The control CT and Magnetic Resonance (MR) showed pneumolabyrinth resolution.

S87 CONCLUSIONS Implosive and explosive forces seems to cause perilymphatic fistula development. Implosive forces are those that cause pressure change in the middle ear space, exerting an external force. Explosive forces are those that exert an internal pressure by increasing cerebrospinal fluid pressure. Once a connection has been established between inner and middle ear, endolymphatic hydrops develops, along with its constellation of symptoms. Pneumolabyrinth is a rare finding on CT, and its detection supports the diagnosis of perilymphatic fistula. Keywords Pneumolabyrinth, perilymphatic fistula, Valsalva maneuver P.1.027 IDENTIFICATION OF PARANASAL SINUSES ANATOMICAL VARIANTS BY COMPUTED TOMOGRAPHY R. Carvalho1, R. Figueroa2 1 Hospital de Braga, Braga, Portugal, 2Georgia Health Sciences University Medical College of Georgia, Augusta, GA, USA

PURPOSE The development of the sinuses occur in a well-established sequence, beginning during embryonic life, around the 3rd and 5th month of pregnancy, and ending between 12–14 years-of-age. Factors not well understood can change this sequence, and lead to the formation of anatomical variants, and these may or may not have clinical implications. Computed tomography (CT) is the method of choice in the evaluation of the paranasal sinuses, and provides valuable information on the anatomy, variants, pathological processes, treatment planning and follow-up. METHODS The authors reviewed CT scans of patients undergoing evaluation examinations. Examinations were performed with volumetric acquisition and were reformatted in multiple planes. The variants were classified into groups. RESULTS The anatomical variants were classified as: frontal (intersinusal cell and hypoplasia), ethmoidal extramural (Agger Nasi, frontal, supraorbital ethmoid, Haller and Onodi cells), ethmoidal intramural (frontal bullar cell, suprabullar cell and ethmoid bulla), esphenoidal (optic nerve and carotid dehiscence, hypoplasia, pterygoid and clinoid pneumatization) and maxillary (posterior fontanella and hypoplasia). The variants not related with any sinuses were classified as others, and includes variations of the uncinate process, middle turbinate bulla, paradoxical middle turbinate, anterior ethmoidal artery, lamina papyracea defects, crista galli and nasal septum pneumatization. CONCLUSIONS A better identification of pneumatization patterns and its anatomic variants is possible because of the improvement of imaging modalities, allowing a precise multiplanar mapping of the anatomic variants. The correct interpretation of some variants is important important because of their implications in mucociliary dreinage, and the therapeutic success of endoscopic endonasal surgery is directly related to the accurate identification and description of these variants. Keywords Paranasal sinuses, anatomical variants, computed tomography P.1.028 NEUROIMAGING FINDINGS IN RENAL FAILURE AND RENAL DISEASE R. Brennan, A. O'Hare, J. Thornton, P. Brennan, S. Looby Beaumont Hospital, Department of Academic Radiology, Dublin, Ireland

S88 PURPOSE Acute and chronic renal failure present diagnostic and performance challenges in CT and MRI. Many renal diseases can result in neurological complications with diagnostic features on radiological imaging. METHODS This illustrative review presents several interesting examples of neuroimaging findings related to renal failure. Examples of many neurological complications secondary to primary renal diseases are radiologically illustrated and reviewed. RESULTS In the acute renal failure setting, use of iodinated contrast can exacerbate same and may be contraindicated. In the chronic renal failure setting, contrast staining of acute or chronic cerebral infarcts can be a diagnostic challenge and/or can mimic a haemorrhage. Use of gadolinium based MR contrast agents is often contraindicated in patients with chronic renal failure because of the risk of nephrogenic systemic fibrosis. Congenital renal abnormalities, particularly those related to spinal dysraphism, will have a number of associated anomalies including a Chiari malformation, a lumbar myelomeningocoele, callosal agenesis or dysgenesis and other anomalies. The incidence of small vessel disease is markedly increased in patients with chronic renal failure, often exacerbated by hypertension. The incidence of cerebral infarction and haemorrhage is increased secondary to hypertension, vasculitis and vasculopathy, all of which can affect the kidneys and the central nervous system (CNS). The entity of posterior reversible encephalopathy syndrome (PRES) is increased with acute renal failure. Subarachnoid haemorrhage and intracranial cerebral aneurysm formation is increased with polycystic kidney disease. The phakomatoses, which are well described, have a number of renal and CNS findings. These include neurofibromatosis type 1, Von Hippel Lindau syndrome and tuberous sclerosis. Renal cell carcinoma classically metastasizes to the brain as hypervascular metastases. Sequelae of chronic renal failure include metabolic renal bone disease with distinct neuroradiological entities such as haemodialysis spondyloarthropathy. CONCLUSION Renal failure poses a challenge to the neuroradiologist in protocolling CT and MRI studies with contrast. We outline rationale for dealing with this. We provide illustrations of the salient imaging features of many congenital, vascular, neoplastic, inflammatory, infectious and metabolic diseases that affect the CNS secondary to primary renal disease or pathology. Keywords Neuroimaging findings, kidney, renal disease P.1.029 IMAGING OF FOREIGN BODIES IN THE HEAD, NECK AND ORBIT D. Mcweeney, J. O'Dowd, L. Galvin, R. Grech, A. O'Hare, J. Thornton, P. Brennan, S. Looby Diagnostic and Interventional Neuroradiology, Beaumont Hospital, Dublin, Ireland PURPOSE In adult populations, foreign bodies in the head, neck and orbit are usually the result of traumatic injury. Surgical materials are also foreign bodies and when they remain in situ can present diagnostic dilemmas. Traumatic foreign bodies are unusual findings and the imaging of such cases is both interesting and potentially challenging to interpret and to subsequently treat. In this poster we outline the useful imaging modalities in foreign body detection in the head, neck and orbit and the main complications thereof. MATERIALS AND METHODS We carried out a review of interesting cases of foreign bodies in the head, neck and/or orbit recorded internally in our department.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS The outlined cases demonstrate the value of different imaging modalities in various scenarios. Pseudoaneurysm formation is the complication of head/neck foreign body impaction most frequently managed by interventional neuroradiologists at our institution. CONCLUSION Foreign body impaction in the head, neck and orbit can give rise to life- and sight-threatening complications. Detection of small foreign bodies or complications caused by a foreign body requires a high index of suspicion. Early diagnosis and management significantly influences the outcome for the patient. P.1.030 NEOPLASTIC AND NON-NEOPLASTIC LESIONS AFFECTING THE SKULL BASE – WHAT DO WE NEED TO KNOW? CLINICAL CASES IN A PICTORIAL ESSAY M. Sarpi, E. Gebrim, M. Garcia, F. Cevasco, M. Daniel, R. Elia, U. Passos, H. Zuppani INRAD - FMUSP, São Paulo, Brazil PURPOSE To exemplify the variety of clinical conditions that may affect the skull base, including inflammatory conditions (skull base osteomyelitis, IgG4 related disease, sarcoidosis and amyloid tumor). To review skull base anatomy, acknowledging possible pathways of intracranial spread. METHODS To demonstrate through clinical cases with computed tomography (CT) and magnetic resonance (MR) imaging pathologies that can affect the skull base, including tumors and inflammatory conditions, some of them with intracranial spread. To highlight key points to be evaluated, with literature and anatomy review, offering tools for the radiologist to work up the differential diagnosis for these cases. Examples of cases that will be demonstrated: neoplastic – juvenile angiofibroma with cavernous fistula, chondrosarcoma, chordoma, invasive pituitary adenoma, meningioma, paraganglioma, metastatic disease, invasive nasopharyngeal carcinoma, esthesioneuroblastoma, among others; non-neoplastic – fibrous dysplasia, skull base osteomyelitis, sphenoid sinusitis with intracranial spread, foreign body in the pontocerebellar cistern, amyloid tumor, among others. RESULTS All cases to be demonstrated represent clinical cases of diseases that involve the skull base, with didactic imaging findings, most of them confirmed through anatomopathologic evaluation. CONCLUSIONS Skull base lesions may be the manifestation of a great variety of pathologies. Some of them primary arise from skull base, as chondrosarcoma, but some of them may secondary involve skull base structures. It is very important to recognize this involvement and to acknowledge anatomic and imaging characteristics that should alert the radiologist for intracranial dissemination of neoplastic and non-neoplastic diseases, leading to proper clinical management of the patients. It is also important to recognize typical features of some lesions thus contributing to the differential diagnosis (in cases of nasoangiofibromas, meningiomas, paragangliomas, etc.). Keywords Skull base, neoplastic and non-neoplastic, imaging evaluation P.1.031 DCE-MRI IN HEAD AND NECK LESIONS: PICTORIAL REVIEW J. Ontañon, I. Vicente, I. Saralegui, A. Cabrera OSATEK MRI Unit, Galdakao, Spain

Neuroradiology (2013) 55 (Suppl 1):S15–S159 OBJETIVE To show the different types of curves obtained with dynamic contrastenhancement magnetic resonance imaging (DCE-MRI) in different pathological head and neck processes. MATERIAL AND METHODS We reviewed 79 T1 perfusion studies performed from June 2012 to May 2013 in 70 patients. The equipment used were Achieva 3 T (Philips) and Avanto 1.5 T (Siemens). 3 T magnet parameters were: 85 dynamics scan every 3,6 sec (total tyme 5,07 m); TR/TE=2,4/1.22; thickness 1'6 mm; Field of view (FOV) 220 x 220; Matrix=124x122; flip angle=10, number of signal acquired=1. 1'5 T equipment parameters were: 50 dynamics scan, obtained every 5 sec (total tyme: 4,28 m); TR/TE 2,67/1,13; thickness 4 mm; FOV 255 x 81; Matrix=166x256;flip angle=10; number of signal acquired=1 A standard bolus of 0,1 mmol/Kg of contrast agent was injected at a rate of 4 or 5 mL/s followed by a bolus of sodium chloride solution injected at a rate of 5 mL/s after the 1- 2th baseline acquisition. All patients underwent morphological series: T2 and DW-weighted sequences,and T1-weighted sequence before and after administration of gadolinium chelate. Patients were referred for suspected malignancy, for staging newly diagnosed tumor or post-treatment control. RESULTS We divided the cases according to the site of involvement : A) salivary glands, B) lymh nodes, C) other tissues of the head and neck or D) miscelanea. We reviewed the curves of: A) 15 pleomorphic adenomas (8 newly diagnosed, 5 persistent/relapsed after surgery), 2 Warthin tumors, 2 parotid cyst and 4 inflammatory processes. B) 7 patients with suspected pathological lymph nodes. C) 4 tongue neoplasms, 2 mouth floor carcinomas, 2 nasopharyngeal neoplasm, 2 benign lymphoid hyperplasia of cavum, 1 trigone retromolar carcinoma, 1 neurinoma, 1 vocal cord lymphoma, 1 esophageal neoplasm, 1 mandibular osteomyelitis/osteoradionecrosis, 1 tonsil carcinoma. D) Other studies included: changes after treatament (surgery and /or radiotherapy) (19) and no pathological changes (5). CONCLUSIONS DCE-MRI is an useful technique in the diagnosis of neoplasms and in many cases can help to distinguish between benign and malignant processes. However, further morphologic features such as sharp or blurred borders, invasion of adjacent structures and clinical signs of malignancy are still important to establish the correct diagnosis. Keywords DCE-MRI, tumor, contrast

Inflammatory, demyelinating and degenerative diseases of the brain P.1.033 SIGNIFICANCE OF COMBINED USE OF MR IMAGING AND PERFUSION SPECT FOR THE EVALUATION OF MULTIPLE SYSTEM ATROPHY T. Ogawa, Y. Kanasaki, S. Fujii, Y. Shinohara, T. Kaminou, F. Miyoshi Tottori University, Yonago, Japan PURPOSE To clarify the significance of combined use of MR imaging and perfusion SPECT on pathophysiological evaluation and differential diagnosis of multiple system atrophy (MSA).

S89 METHOD We evaluated 26 patients with MSA using MR imaging and 99mTcECD SPECT. We considered the significance of combined use of both modalities for the evaluation of MSA on the basis of MR-pathologic correlations. RESULTS Imaging findings of both modalities could be broadly classified into 2 types as follows and were helpful for the differential diagnosis of MSA. 1. Consistent findings on MR imaging and perfusion SPECT: atrophy and signal-intensity changes of cerebellum, middle cerebellar peduncle, brainstem, and/or basal ganglia on MR imaging and hypoperfusion in these regions on SPECT. These findings can be interpreted as severe degeneration of cerebellar white matter and/or severe neuronal loss and gliosis of the basal ganglia. 2. Inconsistent findings on MR imaging and perfusion SPECT: asymmetrical hypoperfusion of basal ganglia or cerebellum on SPECT in spite of no atrophy and/or no signal-intensity changes in these regions on MR imaging. These findings can be interpreted as mild neuronal loss and gliosis in the basal ganglia or mild loss of myelin and axons with mild gliosis of cerebellar white matter. CONCLUSIONS Combined use of MR imaging and perfusion SPECT is useful for the pathophysiological evaluation of MSA and for the differential diagnosis. Keywords Multiple system atrophy, MRI, SPECT P.1.034 CEREBRAL AMYLOID ANGIOPATHY-RELATED INFLAMMATION: FROM CLINICAL PRESENTATION TO NEURORADIOLOGICAL DIAGNOSIS M. Martucci1, S. Sarria1, C. Vert1, M. Toledo2, P. Coscojuela1, S. Siurana1, C. Auger1, A. Rovira1 1

Neuroradiology Unit, Radiology Departmen, Vall d´Hebrón University Hospital, Barcelona, Spain, 2Epilepsy Unit, Neurology Department, Vall d´Hebrón University Hospital, Barcelona, Spain PURPOSE To highlight clinical presentation, radiological findings and outcome of cerebral amyloid angiopathy (CAA)-related inflammation. METHODS We retrospectively reviewed clinical manifestation, CT and MR imaging findings and long-term outcome of nine consecutive patients with CAA-related inflammation, admitted at our institution from February 1994 to May 2010. Eight patients had a diagnosis of “probable” CAA according to the Boston criteria, while one patient a “definitive”CAA based on autopsy sample. For all patients a brain CT scan was acquired when admitted to the hospital and a brain MRI performed within 2–4 days after the onset of symptoms. Clinical and radiological long-term follow-up were evaluated in all patients. RESULTS Patients mean age was 75 years (range, 63–83), and six were women. The most common clinical onset was rapidly progressive cognitive decline in the intercourse of days to a few months, followed by focal neurological sings such as epileptic seizures, headache or stroke-like symptoms. Brain CT showed non-contrast enhanced expansive subcortical hypodense lesions in all patients, most of them unifocal (6/9) and localized in the temporal lobe (4/9). CT lesions corresponded to areas of high signal intensity on the T2-WI sequences without diffusion restriction on apparent diffusion coefficient map, indicating that the signal changes corresponded to vasogenic edema. All patients showed micro/macro lobar cortico-subcortical hemorrhages on T2* sequences. A slight leptomeningeal enhancement was observed in two of the six patients in whom contrast agent was administered.

S90 Clinical symptoms recovered within a few weeks under treatment with corticosteroids or even spontaneously in two patients. MRI follow-up in four patients, performed 2–12 months after treatment, showed resolution of the lesions. Symptomatic disease recurrence was observed in three patients, with new lesions on CT/MR, all localized in the parietal lobes. One autopsy sample confirmed the diagnostic of encephalitis associated with amyloid angiopathy. CONCLUSION CAA–related inflammation represents an uncommon but clinically striking presentation of CAA. A correct diagnosis of this entity is of huge importance as it can allow a timely, proper and often efficacious treatment. Even in the absence of histological data, the early recognition of clinical symptoms and typical radiological features is the key to identify patients with CAA-related inflammation. Keywords Cerebral amyloid angiopathy, CAA related inflammation P.1.035 SUPRATENTORIAL MICROSTRUCTURAL WHITE MATTER ABNORMALITIES IN FRIEDREICH ATAXIA - A DTI STUDY T. Lindig1, B. Bender1, T. Nägele1, U. Klose1, M. Synofzik2, L. Schöls2, S. Mang3 1 Radiologische Universitätsklinik - Abteilung Diagnostische und Interventionelle Neuroradiologie, Tübingen, Germany, 2Neurologische Klinik und Hertie-Institut für klinische Hirnforschung - Abteilung Neurodegeneration, Tübingen, Germany, 3Deutsches Krebsforschungszentrum Heidelberg - Softwareentwicklung für Integrierte Diagnostik und Therapie, Heidelberg, Germany

PURPOSE Friedreich Ataxia is well characterized by progressive neurodegeneration of the dorsal root ganglia, the posterior columns of the spinal cord, the pyramidal and spinocerebellar tracts, the cerebellum and the cerebellar peduncles. However, clinical evidence of non-ataxic symptoms point to an expanded degeneration of nervous tissue even in cortical and subcortical cerebral structures. METHODS Tract based spatial statistics (TBSS) were used to investigate differences between 15 patients and 15 healthy controls along the major white matter tracts without bias. Prior to the TBSS evaluation the diffusion data (3 T Siemens Tim TRIO, 64 directions, 2.5 mm isotropic voxel size, b=2000) was corrected for motion during data acquisition and the corresponding gradient directions were corrected accordingly. Different diffusion measures such as fractional anisotropy (FA), mean diffusivity (MD), the three eigenvalues of the diffusion tensor (L1, L2, and L3), the trace of the diffusion tensor (TR) and radial diffusivity (RD) were investigated independently. RESULTS TBSS showed significant (p<0.05) differences between patients and controls with lower FA and higher MD, L1, L2, TR and RD values in the already known regions of the brainstem, cerebellum and the cerebellar peduncles but also in many major subcortical and deep white matter fiber bundles of the supratentorial brain. CONCLUSION This DTI study reveals structural evidence of non-ataxic symptoms demonstrating microstructural cerebral white matter abnormalities in Friedreich ataxia far beyond previously know infratentorial areas.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Keywords FRDA, diffusion weighted imaging, neurodegeneration P.1.036 SUSCEPTIBILITY-WEIGHTEDIMAGINGINTHEDIFFERENTIATION OF PYOGENIC BRAIN ABSCESSES FROM NECROTIC GLIOBLASTOMAS P. Lai1, T.C. Chuang2, H.C. Chang3, H.W. Chung4, H.S. Lin5, J.H. Fu1, P.C. Wang1, H.B. Pan1 1 Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, 2Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan, 3Brain Imaging and Analysis Center in the School of Medicine at Duke University, Durham, NC, USA, 4Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan, 5Program of Health-Business Administration, School of Nursing, Fooyin University, Kaohsiung, Taiwan

PURPOSE Brain abscess can simulate intracranial necrotic glioblastomas multiforme (GBM) in MRI appearance. The purpose of this study was to investigate the discrimination of abscess and GBMs at susceptibilityweighted imaging (SWI). METHODS SWI was performed in 21 patients with pyogenic brain abscesses and 21 patients with rim-enhancing GBMs at 1.5 Tesla. Three observers assessed independently the intralesional susceptibility signal (ILSS), and analyzed with qualitative (QL) and semi-quantitative (SQ) methods. Logistic regression models were used to distinguishing between two diseases. After receiver operating characteristic curve analysis, area under ROC curve was compared between two different methods in these two diseases. RESULTS In QL analysis, absence of ILSS was more associated with abscess than presence of ILSS when distinguishing abscess from GBM (odds ratio [OR]=15, P=.015). In SQ analysis, ILSS grade 0 and grade 1 was more associated with abscess when distinguishing abscess from GBM (OR =144, P=.001). For distinguishing abscess from GBM, the AUCs of QL model and SQ model were .69, and .91, respectively. SQ model was significantly better than QL model in distinguishing abscess from GBM (P<.001). A derived ILSS cut-off grade of 1 or less was quantified as having a sensitivity of 85.7 %, specificity of 85.7 %, accuracy of 88.1 %, PPVof 90.0 % and NPVof 86.4 % in distinguishing the abscess from GBM. CONCLUSION The use of ILSSs provides a benefit for the differential diagnosis of abscesses and necrotic GBMs. A high-grade ILSS may help distinguish necrotic GBMs from abscesses. The lack of ILSS or low-grade (grade 0 or 1) ILSS can be a more specific sign in the diagnosis of abscesses. Keywords Abscess, glioblastoma, susceptibility-weighted imaging P.1.037 MR PRESENTATION OF CREUTZFELDT-JAKOB DISEASECASE REPORT OF SPORADIC FORM B. Georgievski-Brkic1, M. Radovic-Stefanovic2, A. Terzic-Beljakovic1, B. Vukomancic1, M. Pesovic-Grbovic1, T. Jaramaz-Ducic3, M. Vukicevic3 1

Stroke Hospital Sveti Sava, Radiology Department, Belgarde, Serbia, Clinical Centar Bezanijska kosa, Radiology Department, Belgarde, Serbia, 3 Stroke Hospital Sveti Sava, Neurology Department, Belgarde, Serbia 2

Neuroradiology (2013) 55 (Suppl 1):S15–S159 INTRODUCTION AND PROPOUSE: Creutzfeldt - Jakob disease (CJD) is rare, progressive and fatal neurodegenerative brain disease which often leads to dementia. Types of CJD are sporadic, variant, familial and iatrogenic. CJD belongs to humans and animal’s group of diseases known as transmitted spongiform encephalopathy or prion’s disease. MATERIAL AND METHODS 59 years old female patient was admitted to the Hospital Sveti Sava in Belgrade having amended state of consciousness. Disease started 6months before admittance with instability, progression of cerebellar symptomatology and altered behavior. Personal anamnesis data showed information of eating monkey’s brain 15 years ago in China. We performed MSCT of brain EEG and MR of brain. RESULTS Brain CT showed cerebral and cerebellar atrophy. There was pathological EEG. Brain MRI pointed on hyperintense T2W/FLAIR lesions with restriction of diffusion and no postcontrast enhancement of IS in putamens, heads of nucleus caudatus with bilateral symmetrical abstraction of globus palidus, asymmetrical more right abstraction of pulvinar nuclei, and insulopercular and parahippocampal billateral symmetrical abstraction. Diffusion showed restriction and T2/FLAIR showed signal hiperintensity in cortex, predominantly in temporofrontal regions bilaterally. There were also a signs of cerebral and cerebellar atrophy. We excluded potential differential conditions such as intoxication (CO poisoning, hypoxia) and metabolic diseases (Morbus Wilson). According MR imaging we concluded that the patient was suffering from CJD, sporadic form, which is more frequent and present almost 85 % of all cases of CJD. Lesions of this CJD type usually are in basal ganglia, can be asymmetrical and cortical lesions on T2/FLAIR and diffusion restriction include two cerebral regions. We had autopsy confirmation of this disease. CONCLUSION Along with clinical appearance, EEG, CSF analysis, brain MRI has leading role in precise in vivo diagnose of this rare condition and type of disease. Keywords Creutzfeldt-Jakob disease, MRI of brain, sporadic form P.1.038 FRACTIONAL ANISOTROPY IN THE CENTRUM SEMIOVALE AS A QUANTITATIVE INDICATOR OF CEREBRAL WHITE MATTER DAMAGE IN THE SUBACUTE PHASE IN PATIENTS WITH CARBON MONOXIDE POISONING: CORRELATION WITH CONCENTRATION OF MYELIN BASIC PROTEIN IN CEREBROSPINAL FLUID T. Beppu, S. Fujiwara, K. Ogasawara, M. Sasaki Iwate Medical University, Morioka, Japan PURPOSE Carbon monoxide (CO) poisoning leads to demyelination of cerebral white matter (CWM) fibers, causing chronic neuropsychiatric symptoms. Our previous study suggested that the centrum semiovale in CWM is the main region damaged in the subacute phase after CO inhalation. To clarify whether fractional anisotropy (FA) from diffusion tensor imaging in the centrum semiovale can depict demyelination in the CWM during the subacute phase after CO inhalation, we examined correlations between FA in the centrum semiovale and myelin basic protein (MBP) in cerebrospinal fluid.

S91 METHODS Subjects comprised 30 adult CO-poisoned patients less than 60 years old. MBP concentration was examined for all patients at 2 weeks after CO inhalation. Mean FA of the centrum semiovale bilaterally at 2 weeks was also examined for all patients and 21 age-matched healthy volunteers as controls. After these examinations, presence of chronic symptoms was checked at 6 weeks after CO poisoning. RESULTS Seven patients displayed chronic symptoms, of whom 6 patients showed abnormal MBP concentration. The remaining 23 patients presented no chronic symptoms and no abnormal MBP concentrations, with MBP concentrations undetectable in 20 patients. MBP concentration differed significantly between patients with and without chronic symptoms. Mean FA was significantly lower in patients displaying chronic symptoms than in both patients without chronic symptoms and controls. After excluding the 20 patients with undetectable MBP concentrations, a significant correlation was identified between MBP concentration and FA in 10 patients. CONCLUSIONS The present results suggest that FA in the centrum semiovale offers a quantitative indicator of the extent of demyelination in damaged CWM during the subacute phase in CO-poisoned patients. Keywords Carbon monoxide poisoning, fractional anisotropy, demyelination P.1.039 THE EFFECT OF DISEASE DURATION ON MR RESTING STATE DATA OF MS PATIENTS B. Bender1, E. Charyasz1, L. Zeltner2, P. Rebasso2,3, H.O. Karnath2,3, F. Bischof 2, U. Klose1 1

MR Research Group, Dept. of Diagnostic and Interventional Neuroradiology, University Tübingen, Tübingen, Germany, 2Department of Neurology, University Tübingen, Tübingen, Germany, 3Division of Neuropsychology, Hertie-Institute for Clinical Brain Research, Tübignen, Germany PURPOSE Usually the visible demyelinating lesions in multiple sclerosis (MS) show a random distribution with a predominance in the periventricular WM in MR images. The expected impact on resting-state brain networks should be dependant on the site of the brain lesions. Therefore standard twosampled t-tests expecting an effect that is similar in all patients of one group might not be appropriate to prove disease dependant changes. Goal of the present work, was to test whether group effects in patients with MS exist that might be missed with standard analysis. METHODS Resting state fMRI data were collected from patients with known MS. MR Protocoll:: 153 meassurements, TR/TE 2175/30 ms, 32slices with a voxel size of 3x3x3mm 3 , 0.75 mm gap. Imaging data were preprocessed using SPM8 including slice–timing, motion correction, coregistration, spatial normalization and smoothing using a Gaussian kernel of 10 mm FWHM. Group independent component analysis was performed using the GIFT toolbox- One component that best matched the default mode network (DMN) was identified by spatial correlation coefficients. Data from patients with a short (0-4 years, N=16, mean age 37 years) and long (11+years, N=18, mean age 44 years) disease duration were selected for this study. The DMN component was tested for in group effects by standard SPM analysis. Furthermore the size of the DMN and the distribution of the DMN in the groups was examined.

S92 RESULTS There was no significant difference between the three groups in the twosampled t-test. The average number of voxels with a z-Score>2 in the DMN was increased in the long duration group(1608) compared to the short duration group (1576). If only voxels were counted that had a zScore >2 in at least 80 % of the patients in the normalized group data, 651/618 were found in the short/long group. CONCLUSION While the average size of the DMN increases with disease duration the overlap between patients decreases. The findings suggest that the random individual focal brain damage caused by demyelinating lesions in MS is compensated for by increased activation of other patient specific brain areas. This effect is probably dependant on the site of brain lesions and therefore underestimated in standard group evaluations. Keywords Resting-state fMRI, MS, disease duration P.1.040 INVESTIGATING THE ROLE OF BRAIN JUXTACORTICAL LESIONS IN CORTICAL THICKNESS MEASUREMENTS C. Auger1, D. Pareto1, J. Sastre-Garriga2, Y. Vives-Gilabert3, J. Delgado3, E. Huerga1, M. Tintore2, X. Montalban2, A. Rovira1 1 MRI Unit Radiology Department, Vall D´Hebron Hospital, Barcelona, Spain, 2Neurology Department, Cemcat, Vall D´Hebron Hospital, Barcelona, Spain, 3Pic-Ifae, Universitat Autonoma Barcelona, Barcelona, Spain

PURPOSE The impact of juxtacortical lesions in cortical thickness measurements is still not fully clarified. The aim of this work was to assess if the presence of juxtacortical lesions (JL) could be related to regional brain atrophy at the early stages of multiple scleros is (MS), by means of m easuring brain cortical thickness. METHODS 95 patients with a clinically isolated syndrome (CIS) and 38 patients with a relapsing-remitting MS (RRMS) were scanned on a 3.0 T system. CIS patients were classified in 3 groups: no brain lesions (CISn, n=23), presence of only non-juxtacortical brain lesions (CISnj, n=35), and presence of juxtacortical and non-juxtacortical brain lesions (CISj). RRMS patients were divided in two groups: presence of only nonjuxtacortical brain lesions (RRnj, n=8), and presence of juxtacortical and non-juxtacortical brain lesions (RRj, n=30). JL were identified and manually delineated on FLAIR images. FLAIR images and the corresponding lesion masks were normalized to the MNI template using Statistical Parametric Mapping. A JL probability map was generated for CIS and RR-MS patients. Cortical thickness was measured from the MPRAGE images, using FreeSurfer v5.1. RESULTS Freesurfer outputs were carefully revised, specially checking for accuracy at the sites of occurrence of JL. Significant decreases in cortical thickness (p<0.001, uncorrected) were observed in the following pairs: RR
Neuroradiology (2013) 55 (Suppl 1):S15–S159 P.1.041 EVALUATION VALUE OF MAGNETIZATION TRANSFER MARKERS AS EARLY PREDICTORS OF CLINICAL DISABILITY AND LESION LOAD PROGRESSION IN CLINICALLY ISOLATED SYNDROME A. Royo1, C. Utrilla1, S. Noval2, P.S. Garcia-Raya1, J. Alvarez-Linera3, C. Valencia4, G. Garzon5, C. Oreja-Guevara4 1 Neuroradiology, University Hospital La Paz, Madrid, Spain, 2Ophthalmology, University Hospital La Paz, Madrid, Spain, 3Neuroradiology, Hospital Ruber Internacional, Madrid, Spain, 4Neurology, University Hospital Clínico, Madrid, Spain, 5Radiology, University Hospital La Paz, Madrid, Spain

PURPOSE -To compare the prognostic value of magnetization transfer (MT) parameters with conventional MRI markers, like black holes and infratentorial lesions, and their relationships with disability. -To evaluate the value of MT parameters in clinically isolated syndrome (CIS) as predictors of the future risk to develop black holes, white matter T2 lesions and infratentorial lesions METHODS 17 patients with CIS (McDonald criteria 2005) were followed over 3 years. Neurological explorations were performed every 6 months (using EDSS, Expanded Disability Status Scale as a measure of clinical disability). MRI was performed at the diagnosis and after 3 years, in a 3 T scanner. Volume of infratentorial lesions, T2WI white matter lesions, T1 hypointense lesions and MTR whole brain histograms analysis were calculated using an image processing software (Jim 5.0, Xinapse System) RESULTS Significant correlation (p<0.05) was found between mean MTR at the diagnosis and EDSS at the end of the study (r:-0.64, p:0.019), peak of white Matter MTR at diagnosis and EDSS at the end (r:-0.82, p:0.001), black holes volume at baseline and EDSS at the end (r:0.82, p:0.000) and volume of infratentorial lesions at baseline and EDSS at the end (r:0.75, p:0.002). The correlation was significant between mean MTR (r-0.657, p=0.006)and peak WM MTR (r-0.828, p=0.000)at baseline and white matter T2 lesion load at the end of the study, mean MTR (r-0.665, p=0.005) and peak WM MTR (r-0.814, p=0.000)at baseline and infratentorial white matter lesion load at the end, mean MTR (r-0.687, p=0.003) and peak WM MTR (r0.773, p=0.000) at baseline and black holes load at the end CONCLUSIONS MTR parameters at baseline are associated with disability progression and with the increase of black holes, white matter T2 lesion volume and infratentorial lesion load 3 years after diagnosis. According with our results, quantitative MT parameters could offer useful information about progression of lesions that could be a surrogate of severe focal tissue damage in CIS at earliest clinical stages. Keywords Clinically isolated syndrome, magnetization transfer, prognostic value P.1.042 EVOLUTION OF GADOLINIUM-ENHANCING LESIONS IN CLINICALLY ISOLATED SYNDROME AND RELAPSINGRECURRENT MULTIPLE SCLEROSIS A. Royo1, C. Utrilla1, S. Noval2, R. Frutos1, C. Valencia3, G. Garzon4, J. Alvarez-Linera5, C. Oreja-Guevara3 1

Neuroradiology, University Hospital La Paz, Madrid, Spain, 2Ophthalmology, University Hospital La Paz, Madrid, Spain, 3Neurology, University Hospital Clinico, Madrid, Spain, 4Radiology, University Hospital La Paz, Madrid, Spain, 5Neuroradiology, Hospital Ruber Internacional, Madrid, Spain

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE -To assess the evolution of acute inflammatory lesions in patients with clinically isolated syndrome (CIS) and relapsing-recurrent multiple sclerosis (RRMS) using Magnetic Resonance Imaging (MRI) findings from serially acquired scans. -To compare permanent focal damage induced by previous acute inflammatory lesion (active MS plaque) presenting in the same location in these two groups of patients (CIS versus RRMS). METHODS 17 patients with CIS (McDonald criteria 2005) and 15 patients with RRMS were followed for 3 years. Neurological explorations were performed every six months. MRI was performed at baseline and after three years, using a 3 Tesla scanner (GE, USA). Imaging protocol included: axial dual-echo variable echo Fast Spin Echo, axial fast fluid-attenuation inversion recovery (FLAIR), and T1-weighted conventional SE pre- and postcontrast administration. The volume of gadolinium-enhancing T1 lesions at baseline was measured. The percentage of these lesions that was hypointense at T1WI (“black hole”) in the follow-up MRI at the end the study was calculated, using Jim 5.0 software (Xinapse System), in both groups. RESULTS A strong correlation between the volume of T1 gadolinium-enhancing lesions at baseline and the remaining percentage of hypointenseT1WI lesion at the end of study and the type of disease (RRMS versus CIS) was found (p<0.006). The mean in CIS patients was 0.069 (SD 0.163), and in RRMS patients the mean was 0.541 (SD 0.529). CONCLUSIONS RRMS patients demonstrated more extensive white matter permanent damage after 3 years follow-up of the active MS plaque (enhancing lesion), compared to patients with CIS. The evaluation of permanent damage, both in CIS and RRMS, using the percentage of gadolinium-enhancing lesion that is transformed into a black hole, could be an easy and useful parameter to quantify it. These preliminary findings are in concordance with the poorer clinical prognosis that is observed in RRMS patients compared to patients with CIS. This highlights the development of brain damage in both conditions Keywords Active plaque, clinically isolated syndrome, RR multiple sclerosis

Pediatric neuroradiology P.1.043 FETAL MRI: EMBRYOLOGY, ANATOMY AND PATHOLOGY OF POSTERIOR FOSSA M. Recio1, P. Martínez Ten2, B. Adiego3, J. Pérez Pedregosa4, A. Álvarez1, C. Hayoun1 1

Hospital Universitario Quiron Madrid, Pozuelo De Alarcon, Spain, Delta Ecografia, Madrid, Spain, 3Hospital Universitario Fundacion Alcorcon, Madrid, Spain, 4Hospital La Moraleja, Madrid, Spain 2

PURPOSE The aim of this exhibit is to: - Specify the normal US and MRI anatomy of the developing fetal posterior fossa. - Describe posterior fossa pathologies amenable to prenatal diagnosis - Establish a diagnostic imaging strategy for posterior fossa abnormalities. - Correlation of antenatal imaging features with postnatal clinical features. METHODS 265 fetuses between the 20th and the 37,5th week of gestation were examined employing FIESTA ,SSFSE , diffusion and gradient T1 pulse sequences, using a 1.5 T MR scanner.

S93 RESULTS Posterior fossa malformations are among the most common brain anomalies identified by current fetal imaging techniques. A good knowledge of embryology and anatomy of the posterior fossa is mandatory to analyse the US and MR images. Although US remains the primary imaging method for routine examination of the developing fetal brain, MRI provides better soft-tissue contrast, especially within the PF . However, there are numerous problems concerning classification, pathogenesis and prognosis. We describe posterior fossa pathologies: Chiari‘s malformations, Dandy Walker malformation, vermian agenesis, vermian hypoplasia, rombencephalosynapsis, Joubert syndrome, cerebellar hypoplasia, pontocerebellar hypoplasia, cerebellar atrophy, mega cisterna magna, posterior fossa arachnoid cyst, Blake pouch cyst (delayed closure of the vermis) unilateral cerebellar damage, PHACE syndrome, fetomaternal infection (CMV), cerebellar hemorrhage and meningocele and occipital meningocele. We establish a diagnostic algorithm based on radiological findings. CONCLUSIONS Fetal MRI is a powerful technique used to evaluate the fetal brain, and is also a valuable complement to prenatal sonography. Fetal MRI has higher contrast resolution than prenatal sonography and therefore, allows better differentiation between normal and abnormal tissues. Structural abnormalities such as posterior fossa abnormalities can be sonographically occult on prenatal sonography yet detectable by fetal MR imaging. MR often plays a major role in the evaluation of fetal posterior fossa abnormalities, whose prognosis is often poor. Keywords MRI, fetal cerebellum, posterior fossa P.1.044 MOYAMOYA DISEASE IN CHILDREN - SPECTRUM OF MAGNETIC RESONANCE BRAIN CHANGES K. Nowak, E. Jurkiewicz, P. Daszkiewicz, D. Kuczynski, K. Malczyk IP-CZD, Warsaw, Poland PURPOSE Moyamoya disease (MMD) is a rare cerebrovascular condition. These slowly progressive steno-occlusive changes in the terminal portions of the bilateral internal carotid arteries and their proximal branches result in the formation of a fine vascular network - moyamoya vessels. In children, moyamoya disease typically presents with a transient ischemic attack, ischemic stroke or seizures. The steno-occlusive areas are usually bilateral, but unilateral involvement does not exclude the diagnosis. We present the spectrum of magnetic resonance changes recognized in children with MMD. MATERIAL AND METHODS Our group of patients consists of seven children (3 boys and 4 girls) at age from 2 to 17 years old. All children met the criteria of definite moyamoya disease according to the published guidelines. Children with moyamoya syndrome were excluded. MR brain examinations were obtained with 1.5 scanner. Standard MR protocol with FLAIR sequence, diffusion weighted imaging (DWI) and TOF MR angiography was performed. T1-weighted images after contrast administration were obtained in 5 children. RESULTS Ischemic lesions in watershed distribution were identified in 4 children (chronic infarcts in 3 and acute stroke in 1 patient). In two children we found lacunar infarcts, large infarcts of the left ACA distribution in another two. Additional white matter lesions were recognized in 6 patients (diffuse hiperintense signal in one, several high signal foci in four, extensive multiple lesions in one children). Enlarged perivascular spaces were observed in one patient.

S94 The leptomeningeal ivy sign we noticed in 6 patients. None of our patients had signs of hemorrhage. CONCLUSIONS Varied morphological brain changes, except hemorrhage were observed in patients with MMD due to vascular disease. Although MMD is a rare disease, it is an important cause of cerebral stroke in children. The correct diagnosis is the key to proper treatment procedures (surgical revascularization is thought to improve cerebral perfusion, and to reduce the risk of subsequent stroke). Keywords Moyamoya disease, brain changes P.1.045 MAGNETIC RESONANCE IMAGING OF THE SPINAL CORD IN CHILDREN AND ADOLESCENTS WITH MULTIPLE SCLEROSIS E. Jurkiewicz1, K. Nowak1, K. Kotulska2, K. Malczyk1, D. Chmielewski2, M. Bilska2 1

The Children's Memorial Health Institute, Department of Diagnostic Imaging, Warsaw, Poland, 2The Children's Memorial Health Institute, Department of Neurology, Warsaw, Poland PURPOSE The purpose of our study was to determine the prevalence of spinal cord lesions revealed by magnetic resonance (MR) imaging in children and adolescents with clinically definite multiple sclerosis (MS). MATERIAL AND METHODS We retrospectively evaluated the spinal cord magnetic resonance examinations in group of MS patients consisted of 54 children, (37 girls and 17 boys), aged from 7 to 18.5 years (mean 13.8 years). All children met the criteria of clinically definite MS and had typical MS lesions revealed in the brain imaging. MRI of the spinal cord was performed on 1.5 T scanner using a spinal phased array coil. The entire length of the spinal cord was visualised with T1-,T2-weighted sagittal and axial images and T1-weighted images following contrast administration (0.1 mmol/kg). The total lesion count, lesion location, and gadolinium enhancement were analyzed. RESULTS Spinal cord lesions were identified in 35 (64.8 %) patients. In 19 of 54 patients, (35.2 %) we didn’t find any lesions. Contrast enhancement were noticed in 13 of 54 patients (24.1 %). 22 of 54 patients (40.7 %) had less than 5 lesions. 13 of 54 (24.1 %) children had more than five lesions. Four of them (7.4 %) had uncountable, diffuse lesions. The lesions were located within the cervical and thoracic regions of the spinal cord in 29 patients, in the cervical region only in 4 children, and in the thoracic region only in 3. None of these patients met the diagnostic criteria for neuromyelitis optica (NMO). CONCLUSION The prevalence of spinal cord lesions in children and adolescents with MS is high. Therefore, spinal cord MRI with contrast should be performed in every child suspected as having MS. Keywords Multiple sclerosis, spinal cord, magnetic resonance imaging P.1.046 CASE PRESENTATION OF DIASTEMATOMYELIA. HOW IMPORTANT TO MAKE PRENATAL DIAGNOSIS OF NEURAL TUBE ANOMALY? A. Jasovic, S. Dowlut, T. Ghoorah Apollo Bramwell Hospital, Moka, Mauritius

Neuroradiology (2013) 55 (Suppl 1):S15–S159 The aim of this study was to discuss about new concept of early diagnosis of some dysraphism and possible prevention of spinal cord irreversible damage. Prenatal knowledge of spinal cord anomalies is important for prenatal counseling as well as surgical treatment. Knowledge of a diastematomyelia in addition to an MMC aids the pediatric neurosurgeon in the surgical planning. Presenting a case of diastematomyelia in a 8 year old boy with good outcome we would like to point out importance of early diagnosis. MRI of the spine showed complete splitting of the cord into two halves in the midline at D10 vertebra by a bony projection from the same vertebra associated with segmentation defects was seen. Surgery was performed and the postoperative period was uneventful and child was able to recover his bladder function fully. We discussed literature data about prenatal diagnosis of spinal cord anomaly. It is suggested that fetuses with sonographically diagnosed bony abnormalities of the spine may benefit from further evaluation with fetal MRI and that fetal MRI identified additional spinal cord anomalies in 10 % of cases referred for evaluation of sonographically detected bony spine anomalies. In particular, fetal MRI showed sonographically occult diastematomyelia and segmental spinal dysgenesis. We would suggest new diagnostic algorithm for urinary incontinence assessment in children. More precise ultrasound investigations for foetal neural tube anomaly are recommended. Is it possible to have fetal neuroradiology specialist in a small environment like Mauritius? Keywords Diastematomyelia, meningocele, neurogenic bladder P.1.047 SPECTRUM OF NEURORADIOLOGICAL FINDINGS IN CHARGE SYNDROME: A PICTORIAL REVIEW T. Demerath1, M. Krüger2, S. Meckel1 1

University Hospital Freiburg, Department of Neuroradiology, Freiburg, Germany, 2University Hospital Freiburg, Department of Child and Youth Health, Freiburg, Germany PURPOSE CHARGE is an acronym for a highly variable multiorganic malformation syndrome: Coloboma, congenital Heart defects, ChoanalAtresia, Retardation of Growth and Development, Genital Hypoplasia and Ear-Anomalies. Due to various neurological, ophthalmological, and ENT manifestations of affected patients, such as congenital deafness, orbital malformations, vestibular symptoms or cranial nerve dysfunction, neuroradiologists are often confronted with broad spectrum malformations. To review neuroradiological imaging findings of these CHARGE malformations. METHODS All cranial and head & neck malformations of CHARGE patients including detailed analysis of clinical findings, incidences of different anomalies, and neuroradiological findings are systematically overviewed. A pictorial review of common and rare anomalies from our own series of CHARGE patients is presented. RESULTS Current clinical diagnostic criteria of CHARGE syndrome are shortly reviewed. Cranial and head & neck findings include malformations of external, middle and inner ear, ocular anomalies, choanal atresia, facial anomalies, cleft lip and palate, cranial nerve anomalies, variable supraand infratentorial brain malformations, hypothalamic and pituitary dysfunction, and arterial and venous vascular anomalies of brain and skull base. Thin-slice computed-tomography and MRI-protocols of skull base, facial skeleton, temporal bone and/or brain may be obtained for clinical and preoperative diagnostics, e.g. prior to a cochlear implant. We demonstrate imaging findings of common (coloboma, choanal atresia, and semicircular canal atresia) and rare malformations

Neuroradiology (2013) 55 (Suppl 1):S15–S159 (microophthalmia with persistent hyperplastic primary vitreous, ICA hypogenesis, bilateral petrosquamous sinus). CONCLUSIONS CHARGE syndrome may affect patients with many different cranial and head & neck malformations. As neuroradiological imaging is often performed, in particular prior to surgical procedures (e.g. cochlear implant), neuroradiologists should be aware of imaging spectrum of common and rare malformations. In particular, detection of vascular anomalies (e.g. petrosquamous sinus) may be of importance for surgical planning. Keywords CHARGE, cranial malformations, vascular anomalies P.1.048 LEIGH DISEASE A. Bocchio1, G. Voltolin2, D. Machado1, T. Meloni1 1

General Hospital U. Parini, Department of Radiology, Aosta, Italy, Beauregard Hospital, Department of Neuropsychiatry, Aosta, Italy

2

PURPOSE Leigh syndrome is an early-onset, progressive, neurodegenerative disorder, exhibiting considerably variable clinical signs, symptoms, onset time and disease course. Diagnostic tests include magnetic resonance (MR); lactate and pyruvate levels from plasma, cerebrospinal fluid, or both; mitochondrial morphology from tissue biopsy and mitochondrial gene analysis. Advances in technology of neuroimaging are useful in the diagnosis and monitoring of mitochondrial diseases. METHODS We present the case of a family with two children, both eutocic delivered. General, neurological and psychomotor development of both were normal, until the age of 4/5 months. At this age, the first child (female) presented progressive severe psychomotor deterioration and respiratory dysfunction and died, at he age of 9 months, without a diagnosis. The second child, (male) born 5 years after, as well presented, at the age of 5 months, progressive hypotonia and psychomotor regression. MR revealed only non-specific neurodegenerative features. The clinical conditions progressive worsened (dystonia, nystagmo, seizures, swallowing dysfunction and respiratory disturbances) and required domiciliar nursing. Genetic analysis, performed on biological material of both children (stored sample, for the first child) revealed an omozygosis mutation of NDFUFS4 (c462, A delection) in both of them. A mitocondrial disorder was supposed. MR was performed on a 1.5 T GE, with SE, FSE e FLAIR sequences, T1, DP, T2, IR T1-T2 weighted images and DWI. The findings were bylateral, symmetric hyperintensities, on T2 and FLAIR images of basal ganglia (putamina), thalami, brainstem (peri-aqueductal gray matter, subthalamic nuclei, pons and medulla) and cerebellar dentate nuclei. General brain atrophy. Bilateral and symmetric restriction of DWI , with increased ADC values, was evident in frontal cortex (F1-F2). RESULTS MR findings (symmetric areas of T2 prolongation in the basal ganglia, periaqueductal region and cerebral peduncles, with putaminal involvement) were a consistent feature for Leigh disease and definitly helped to define the diagnosis. CONCLUSIONS MR has become the primary imaging modality in patients with leukodystrophy and plays an important role in the identification, localization and characterization of underlying white matter abnormalities in affected patients. MR has also been extensively used to monitor the natural progression of various white matter disorders and the response to therapy. Keywords Leigh, MR, leukodystrophies

S95 P.1.049 ADVANCED MR IMAGING TECHNIQUES TO REFINE THE CONCEPTUAL APPROACH IN PEDIATRIC WHITE MATTER DISEASES A. Allmendinger1, A. Burke2, N. Viswanadhan1, S. Prabhu1 1 Boston Children's Hospital, Harvard Medical School, Boston, MA, USA, 2Franciscan Children's Hospital, Boston, MA, USA

PURPOSE Pediatric leukodystrophies are complex group of diseases that result from abnormal primary myelination or secondary myelin/neuronal degeneration. We will provide a systematic clinico-radiological conceptual approach to pediatric leukodystrophies, and present cases of specific disorders with specific patterns of abnormality. In addition, we will elaborate the use of MR spectroscopy and diffusion-weighted imaging in the diagnostic algorithm that aid in making a more specific diagnosis, or narrow the differential diagnoses. APPROACH Imaging studies obtained for pediatric patients with proven pediatric white matter disease from our tertiary care institution over an 8 year period (2004–2012). We describe important imaging features of each disease narrowing the differential diagnosis of this complex group of diseases, which guides the radiologist and clinicians in planning the most appropriate work-up and tailor laboratory tests. DISCUSSION Use of a conceptual approach in conjunction with the clinical features can help narrow the differential diagnosis. In this clinical-radiological approach, we divide the disorders into groups based on the distribution of the abnormality, nature of lesions, neurological features and degree of temporal progression. MR spectroscopy and DWI data is merged with the structural and clinical characteristics to help refine the diagnosis pathway. Examples of grouped disorders include leukodystrophies presenting with macrocephaly, hypomyelination, predominant cerebral white matter involvement, deep grey matter/brainstem involvement or cerebellar hemispher involvement. Specific diagnostic patterns are seen in patients with metachromatic leukodystrophy, globoid cell leukodystrophy, Saposin B deficiency, Canavan disease, Alexander disease, Sulfite Oxidase deficiency, Leigh Syndrome, Glutaric Aciduria Type-1, Pelizaeus-Merzbacher disease and Mitochondrial Encephalopathy, Lactic Acidosis, with Stroke-like episodes (MELAS), LBSL, megalencephalic leukoencephalopathy with cysts, pyruvate carboxylase deficiency, fucosidosis, X-Linked Adrenoleukodystrophy and Maple Syrup Urine Disease (MSUD). We emphasize utility of diffusion-weighted imaging and MR spectroscopy in diagnosing some of these conditions. SUMMARY This review illustrates the value of the combined clinical and radiological approach to pediatric leukodystrophies. We highlight specific MRI patterns of numerous common and unusual white matter diseases and provide a structured algorithm to aid in narrowing the differential, and in some cases, make a accurate, initial diagnosis. We show how judicious use of MR spectroscopy and diffusion-weighted imaging can help refine the diagnostic algorithm. Keywords Leukodystrophy, MRI, diffusion tensor imaging P.1.050 CONGENITAL SPINAL MALFORMATIONS DEMYSTIFIED A. Allmendinger1, A. Burke2, N. Viswanadhan1, S. Prabhu1 Boston Children's Hospital, Boston, MA, USA, 2Franciscan Children's Hospital, Boston, MA, USA

1

S96 PURPOSE Congenital abnormalities of the spine and spinal cord, or spinal dysraphisms, are often complex and variable in imaging appearance. The purpose of this exhibit is: 1) to review normal embryological development of the spinal cord as discreet anomalies can generally be traced to a specific failure of embryogenesis, and 2) to classify and review neuroimaging manifestations of various congenital malformations of the spine and spinal cord. METHODS Imaging studies obtained for pediatric patients with proven congenital spinal malformations from our tertiary care institution over an 8 year period (2004–2012). MRI images were obtained on both 1.5 and 3 Tesla magnets (majority on 3 Tesla). Additionally, imaging of fetal MR obtained on 1.5 Tesla magnets will be reviewed. We describe important embryological concepts of spinal development, and neuroimaging manifestations of each malformation narrowing the differential diagnosis of this complex group of diseases. RESULTS We will provide an overview of normal embryologic development of the spinal cord including gastrulation, and primary and secondary neurulation (i.e. canalization and retrogressive differentiation. We will first discuss open spinal dysraphisms (myelocele and myelomenigocele) and associated Chiari type II malformation. Closed spinal dysraphisms are categorized into those with a subcutaneous mass (lipo/myelomeningocele, terminal myelocystocele, and meningocele). Or, those without a subcutaneous mass, which are subcategorized into simple dysraphic states (filar lipoma, tight filum terminale spectrum, persistent terminal ventricle, and dermal sinus), and complex dysraphic states including split notochord spectrum (dorsal enteric fistula, neurenteric cysts, and diastematomyelia), and disorders of hypogenesis/agenesis portions of the spine (caudal regression syndrome and segmental spinal dysgenesis). Lastly, we will discuss congenital spinal lipomas including lipomas without dural defect, and lipomas with dural defect. CONCLUSION This review illustrates the value of the combined embryologic and radiological approach when attempting to recognize typical neuroimaging manifestations of pediatric spinal cord malformations. Upon completion of this exhibit, the viewer will be able to accurately categorize these congenital spinal malformations and lipomas, as well as understand the underlying developmental pathology. Keywords Dysraphism, spine, lipoma P.1.051 THE ROLE OFADVANCED TECHNIQUES IN MR NEUROIMAGING IN SURGICAL MANAGEMENT OF BRAINSTEM-EXPANDING LESIONS IN CHILDHOOD

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS We reviewed all cases of brainstem expanding lesions treated in our institution in the last 13 years. There were 45 cases of brainstem gliomas, 24 surgically treated. We also include a case of a hemorrhagic cavernoma in the pons because the surgical management was similar to those tumors. Imaging protocol before the surgery included magnetic resonance imaging (MRI) and multidetector computed tomography (MDCT). MRI study included T2WI, Fluid Attenuation Inversion Recovery sequences, T1 pre and post-gadolinium and diffusion weighted images. MR-angiography and 3D T1 sequences were obtained in most of the cases. 20 of the cases also had MRS and DTI before the surgery. RESULTS Indications for surgical treatment brainstem cavernomas and brainstem tumors in children are based on imaging findings. The role of neuroimaging in the surgical planning of brainstem spaceoccupying lesions and as a guide during the surgical act is crucial in this area We found a good correlation between imaging and surgery findings, etiologic diagnosis and the location of risk structures; discrepancies between the degree of malignancy in neuroimaging and the pathology results were found, specially in cases were advanced techniques were not available. CONCLUSION There have been huge advances in the field of neurosurgery and today the brainstem is no longer regarded as an inoperable region. Preoperative planning based on modern neuroimaging techniques and advances in other fields allows brainstem surgery to be performed with acceptable morbidity and mortality rates We will show the contribution of new imaging techniques in making the surgical decision (selecting the approach, marking the “risk points” before surgery, vascular mapping, white matter tracts delimitation), as a guide during the surgical act and in the follow up Keywords Brainstem expanding lesions, advanced neuroimaging, surgical planning

Spine, Diagnostic imaging P.1.052 THE ROLE OF MR TRACTOGRAPHY OF MEDULLA AND CERVICAL SPINE IN TREATMENT OF TUMORS AND TUMOR-LIKE LESIONS E. Maj1, A. Cieszanowski1, M. Prokopienko2, P. Kunert2, A. Marchel2, O. Rowinski1 1

C. Utrilla1, A. Royo1, F. Carceller2, A. Alvarez-Muelas1, P.S. GarciaRaya1, A.F. Fernandez-Prieto1, G. Garzon3 1

Neuroradiology, University Hospital La Paz, Madrid, Spain, 2Pediatric Neurosurgery, University Hospital La Paz, Madrid, Spain, 3Radiology, University Hospital La Paz, Madrid, Spain PURPOSE -To review the role of neuroimaging with special attention in new neuroimaging techniques (MR-spectroscopy, diffusion fiber-tracking, 3D sequences) in the management of brainstem-expanding lesions, in selecting the approach, planning the surgery and during the surgical act. -To describe our experience in the management of brainstem gliomas in pediatric population, highlighting the role of neuroimaging in presurgical planning.

Medical University of Warsaw, 2nd Department of Clinical Radiology, Warsaw, Poland, 2Medical University of Warsaw, Chair and Department of Neurosurgery, Warsaw, Poland PURPOSE The purpose of this study was to assess the relation of tumors and tumor-like lesions to pyramidal tracts of medulla oblongata and cervical spine and correlation with histopathology result and patients’ motor function before and after the operation. METHODS In 9 patients (6 women, 3 men) aged 19–56 years MR tractography of medulla and cervical spine (20 directions) and morphologic sequences including 3DT1GRE, T2TSE and T1TSE were performed on 1.5 T MR scanner. One patient was excluded from the analysis due to diagnosis of SM. Lesions were classified according to their relation to pyramidal tracts into four categories: type I-normal pyramidal tracts, type II-fibers

Neuroradiology (2013) 55 (Suppl 1):S15–S159

S97

pressed, displaced or separated, type III-fibers partially disorganized, type IV-fibers completely disorganized. All lesions were correlated with histopathology and patients’ motor functions before and after surgery were compared. RESULTS Type I was demonstrated in 1 patient (hemangioblastoma), without deficits before and after surgery, type II in 4 patients (hemangioblastoma, astrocytoma, 2 ependymomas), in whom transient numbness of the upper extremity was occasionally encountered, type III in 1 patient (astrocytoma) with discrete monoparesis before surgery and without symptoms after operation, type IV in 2 patients (PNET and ependymoma) with paresis of upper extremities, in whom tetraplegia was observed after surgery. CONCLUSIONS The appearance of pyramidal tracts of medulla oblongata and cervical spine on MR tractography in patients with tumors and tumor-like lesions shows good correlation with neurologic evaluation in terms of patients’ motor function and may be valuable in predicting patients outcome after surgery. Keywords Spinal tumor, DTI tractography, pyramidal tracts

morphological measurements between the subjects with spinal cord compression compared to those without compression. DTI parameters showed no significant difference between subgroups with and without signs of compression, but we proved statistically significant decrease in FA and ADC values at the lower spinal cord levels (maximal compression site or C5/6 level in subjects without compression) compared to the reference C2/3 level in both subgroups. CONCLUSION The prevalence of ASCCC in our group is higher than previously reported, the presence of the spinal cord compression is documented by the significantly different morphological measurements compared to the subjects without compression. In mostly asymptomatic subjects we found no significant influence of the spinal cord compression on DTI parameters at this stage, but there seem to be physiologic changes of FA and ADC values between different spinal cord levels irrespective of the spondylotic compression, which should be taken into account in case of individual evaluation. The predictive significance of different morphological and DTI parameters remains to be established in future prospective evaluation of larger group of subjects. Keywords Spinal cord compression, cervical myelopathy, diffusion tensor imaging

P.1.053 CERVICAL SPINAL CORD COMPRESSION: PREVALENCE AND DIFFUSION TENSOR IMAGING DATA ANALYSIS

P.1.054 PREDICTION OF CARTILAGE ENDPLATE HERNIATION IN MRI

M. Kerkovsky1, J. Bednarik2,3, B. Jakubcova1, Z. Kadanka 2, Z. Kadanka Jr.2, M. Nemec2, I. Kovalova2, A. Sprlakova-Pukova1

E. Joe, J.W. Lee, G.Y. Lee, S.E. Cho, H.S. Kang Seoul National University Bundang Hospital, Seong Nam, South Korea

1

Department of Radiology, University Hospital Brno and Masaryk University, Brno, Czech Republic, 2Department of Neurology, University Hospital Brno and Masaryk University, Brno, Czech Republic, 3 Central European Institute of Technology, Masaryk University, Brno, Czech Republic PURPOSE Degenerative changes of the cervical spine leading to spinal canal narrowing and spinal cord compression might represent the cause of the cervical spondylotic myelopathy (CSM). The spinal cord compression, however, may be asymptomatic as well and its prevalence is not exactly known. The purpose of the study is to determine the prevalence of asymptomatic spondylotic cervical cord compression (ASCCC) in a general population above the age of 40 and to analyze the diffusion tensor imaging (DTI) parameters as potential marker of subclinical pathological changes of the compressed spinal cord. METHODS The study group comprised 69 randomly chosen volunteers recruited irrespective of the presence of signs of CSM, 40 women and 29 men, aged 65 years (median), range 42–82 years. All subjects underwent MR examination on a 1,5 T MR device. The imaging protocol included conventional sequences in sagittal and axial plane and DTI axial scans. Imaging data analysis comprised morphological measurements including spinal cord cross-sectional area, spinal cord and spinal canal cross-sectional diameters and measurements of ADC and FA values derived from DTI data. These parameters were compared between different levels of the spinal cord and between subgroups of patients distinguished by the presence of the spinal cord compression using non-parametric statistical testing. RESULTS MRI signs of cervical cord compression were found in 38 individuals (55.1 %). The T2 hyperintensity of the spinal cord was present in 3 subjects (4.3 %). Clinical signs of symptomatic CSM were found in 2 cases (2.9 %). We found significant differences in several

PURPOSE To evaluate spinal MR images for disc herniation with cartilage endplate herniation (DH-CEP) to determine the reliable MRI findings. MATERIALS AND METHODS Among seventy-three patients who underwent spinal MRI and microdiscectomy between March 2005 and January 2009, Thirtyseven patients were diagnosed as DH-CEP confirmed at surgery. We assessed the morphologic features of the posterior corner (a. Lumbar posterior marginal node, b. Dorsal corner defect, c. Modic change and d. Posterior osteophyte), mid-endplate (a. Endplate irregularity, b. Modic change), and heterogenous dark signal intensity of extruded material. Chi-square test and multiple logistic regression analysis with age, BMI, and sex as covariates were used for analysis. Receiver operating characteristic (ROC) curve was obtained by scoring system using the statistically significant 6 MRI findings (0~6). RESULTS In patients more than 60 years of age, DH-CEP were more commonly found than in the younger age group (p=.037). In the area of MRI findings, lumbar posterior marginal node, posterior osteophyte, Modic change of the posterior corner, mid-endplate irregularity, Modic change of the mid-endplate, and heterogeneous dark signal intensity of extruded material were significantly more frequent in DH-CEP (.000
S98 P.1.055 A CASE OF A PRESACRAL MYELOLIPOMA: IMAGING FINDINGS AND DIFFERENTIAL DIAGNOSIS CHECKLIST OF OTHER PRESACRAL MASSES C. Gagliardo, G. Falanga, G. La Tona, A. Lo Casto, M. Midiri, R. Lagalla DI.BI.MEF., Radiology Section, University of Palermo, Palermo, Italy PURPOSE There have been many reports describing adrenal myelolipoma but there have been only few reports of extraadrenal myelolipoma. We describe a case of an elderly woman with lower back pain due to age-related spondyloarthrosis and mild discopathy with a presacral myelolipoma as incidental finding. We also discuss about common and uncommon imaging findings of other presacral masses. METHODS A 74 years-old woman came to our observation to perform an MRI of the lumbar spine for typical lumbar back pain. MR imaging revealed, in addition to the signs of mild scoliosis and spondylo-disc-arthrosis, a presacral mass showing heterogeneously high signal in all sequences and almost completely suppressed on inversion recovery sequences for fat tissue and not showing significant enhancement after i.v. administration of contrast medium. CT imaging confirmed the fatty nature of the lesion without any sign of bone involvement. RESULT CT and MR imaging findings were most consistent with a diagnosis of a rare presacral myelolipoma. Our hypothesis was confirmed at histopathologic analysis which showed a mixture characterized predominantly by mature adipocytes and hematopoietic cells including erythroid, myeloid, and megakaryocytic elements without mesenchimal tissue elements. CONCLUSIONS We have reported a case of one of the rarest presacral masses and we have emphasized the role of imaging in the differential diagnosis of other presacral masses inclunding liposarcomas, teratomas, dermoids, epidermoids, chordomas, schwannomas and anterior sacral meningoceles. Keywords Myelolipoma, presacral masses, differential diagnosis P.1.056 LUMBAR INTRADURAL DISK EXTRUSION AND UNUSUAL MIMICS G. Fletcher1, J. Hoxworth1, D. Black2, T. Lidner1 1 Mayo Clinic Arizona, Scottsdale, AZ, USA, 2Mayo Clinic, Rochester, MN, USA

PURPOSE Intradural disk extrusions in the spine are rare. In this poster exhibit, we present a case of surgically proven lumbar intradural disk extrusion and review differentiating features of other uncommon intradural spaceoccupying lesions. METHODS The radiology teaching file at our institution was reviewed, and a single case of surgically confirmed intradural disk extrusion was identified. The clinical history, MRI, and intraoperative findings of this index case are presented. Differential diagnosis of a lumbar intradural mass is reviewed, and two additional uncommon cases of intradural gas-filled cyst and catheter tip granuloma are highlighted. RESULTS 42 year-old man with subacute bilateral sciatica presented to the Emergency Department because of worsening pain and new onset urinary retention. Lumbar spine MRI demonstrated an ovoid intradural mass

Neuroradiology (2013) 55 (Suppl 1):S15–S159 with heterogeneous T1 and T2 signal and peripheral rim enhancement. Surgical resection confirmed the diagnosis of intradural disk extrusion. The presence of additional extruded disk material in the ventral epidural space differentiated this case from other intradural space-occupying lesions, including non-neoplastic masses such as intradural gas-filled cyst and catheter tip granuloma. CONCLUSION With increased awareness of rare non-neoplastic intradural masses, a more accurate differential diagnosis can be offered on pre-operative imaging. Keywords Intradural disk extrusion P.1.057 MR IMAGING FINDINGS OF SPINAL ARTERIOVENOUS FISTULA S. Cho, J. Lee, E. Kim, G. Lee Department of Radiology, Seoul National University Bundang Hospital, Gyeongi-do, South Korea PURPOSE To evaluate MR findings of spinal arteriovenous fistula (AVF) focusing on the expectation of fistula point, and differentiation of types of AVF METHODS Thirty-two patients (M:F =24:8, mean age 59, range, 3-81 yr ) who underwent spinal angiography for suspection of spinal AVF from 2003, April to 2013, April were included in the study. The following findings were analyzed on spine MR images by two radiologists in consensus who were blinded to the clinical and angiographic findings: (a) longitudinal distribution of multiple small abnormal vessel flow voids (VFV) (even or uneven and if uneven, describe most crowded level), (b) axial location of VFV on cord pial surface (both even, ventral dominancy, dorsal dominancy), (c) presence of epidural VFV, (d) longitudinal extent of T2-high signal in the spinal cord (e) presence contrast enhancement in the spinal cord. MR imaging findings were related with spinal angiography. Most crowded VFV level on MR was related with fistula level on angiography. Axial location of abnormal VFV on cord pial surface and presence of epidural VFV was related with type of AVF. Retrospective chart review was done by one radiologist, focusing on the symptom duration before MR. Symptom duration was related with longitudinal extent of T2-high signal and presence of enhancement in the spinal cord. RESULTS There were 18 patients with spinal dural AVF, seven with perimedullary AVF, three with epidural AVF, one with traumatic AVF and three with normal. Uneven longitudinal distribution of VFV was seen at 17 of 32 patients. In dural AVF, dorsal dominance of VFV was more common (17 of 18, 94.4 %) on MR. However, in perimedullary AVF, ventral dominance of VFV was more common (six of seven, 85.7 %). Epidural VFV were only seen in five patients with the epidural AVF. Extent of spinal cord edema or presence of cord enhancement was not correlated with duration of symptom. CONCLUSIONS Most crowded level of VFV was well matched with fistula level in the two level differences in most cases. Spinal dural AVF showed dorsal predominancy of VFV, but spinal perimedullary AVF showed ventral predomiancy of VFV, which can be a clue to differentiate. Keywords Spinal AVM, perimedullary AVF, spinal dural AVF P.1.058 CYSTIC DILATATION OF VENTRICULUS TERMINALIS - A CASE REPORT V. Boskovic, B. Georgievski Brkic, G. Milenkovic, V. Debeljkovic, B. Vukomancic, D. Veljkovic Stroke Hospital Sveti Sava, Department of Radiology, Belgrade, Serbia

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Ventriculus terminalis is a developmental anomally, presenting as a small oval ependymal lined space within the conus medullaris, which has the same signal intensity as CSF. It is rare pathology in adults.Rarely the terminal ventricle may dilatate and have large dimensions.Patients can have a variety of clinical symptoms: from low back/leg pain to weakness of lower limbs, bladder dysfunction etc. MATERIALS AND METHODS We are presenting a 46 year old female patient with complaint of low back/leg pain. MRI(1,5 T GE) exam was performed ussing routine protocol which include T2W, T1W, and postcontrast sequences. RESULTS MR images showed a large cystic dilatation of ventriculus terminalis as well circumscribed cystic lesion within conus medullaris, extending from superior end plate of TH12 to midline of L1.The lesion has the same signal intensity as CSF on all MRI sequences.Dimension of lesion are 41 mm craniocaudally, 16 mm anteroposteriorly and 17 mm mediolaterally. There is no enhancement after admission of contrast media. CONCLUSION Cystic dilatation of ventriculus terminalis is rare pathology in adults and should be differentiated on MR images from other lesions like ependymomas, astrocytomas, etc. Therefore, images with application of contrast media must be performed. Keywords Cystic dilatation, conus medullaris, ventriculus terminalis P.1.059 NOTOCHORDAL CANAL PERSISTENCE A. Bocchio, D. Machado, A. Rosano, D. Furfaro, T. Meloni General Hospital U. Parini, Department of Radiology, Aosta, Italy PURPOSE Persistence of the notochordal canal is a rare anomaly, first described in 1891 by Musgrove. Only a few cases have been reported in the literature. Although it has been cited as a structural route for the spread of infection from one disk level to another, it is usually asymptomatic and discovered as an incidental finding on images. METHODS We present a case of a young male (22 years old), occurred at emergency for back pain. Lateral radiograph of the lumbar spine showed a sclerotic rimmed central channel at L4, that flared at the vertebral endplate to merge with the disk space. About 2 months before, after minor trauma, it had been misdiagnosed on radiograms. The assessment of current plain films and analysis of previous radiograms indicated the need for taking a developmental anomaly into consideration. Based on CT of lumbar spine performed, a final diagnosis of a persistent notochordal canal was established. RESULTS The presence of a notochordal canal may result in a change in the shape of the vertebral body seen on plain films, CT scans, or MR images. In some instances, the presence of a persistent notochordal canal may not result in an appreciable change in the plain film appearance of the vertebral body and may be evident only on CT or MR studies. The true frequency of this malformation may be underestimated. CONCLUSIONS A persistent notochordal canal is a rare anomaly that is generally discovered by chance. In spite of its rare occurrence, the characteristic features of a persistent notochordal canal should be known by radiologists, particularly to avoid misinterpretation in post-traumatic patients

S99 The radiographic appearance of this entity is characteristic and usually does not require further investigation. However, in some cases plain films may fail to depict this appearance, and computed tomography or magnetic resonance imaging (MRI) is required for final diagnosis. Keywords Notochordal persistence, plain films, CT P.1.060 SUBACUTE COMBINED DEGENERATION OF THORACIC AND LUMBAR SPINE - CASE REPORT M. Baptista, M.J. Silva, A.M. Reis Hospital Pedro Hispano, Matosinhos, Portugal Subacute Combined Degeneration (SCD) of spinal cord refers to degeneration of the posterior and lateral columns of the spinal cord as a result of vitamin B12 deficiency. This condition can result due to a dietary deficiency of B12, malabsorption in the terminal ileum, lack of intrinsic factor secreted from gastric parietal cells, low gastric pH inhibiting attachment of intrinsic factor to ileal receptors. The onset is gradual and uniform. The pathological findings of SCD consist of patchy losses of myelin in the dorsal and lateral columns. Patients present with weakness of legs, arms, trunk, tingling and numbness that progressively worsens. Vision changes and change of mental state may also be present. Bilateral spastic paresis may develop and the pressure, vibration and touch sense are diminished. Magnetic Resonance Imaging (MRI) of the spinal cord usually shows increased signal intensity on T2-weighted images in the posterior, lateral, and sometimes anterior columns. Lesions typically occur in the thoracic and cervical spinal cord. We report a case of a 47 years old woman, admitted to the emergency department with history of progressive bilateral lower limb weakness and lumbar pain with no bowel, bladder or sensory symptoms. There was no traumatic history. At the neurological examination there were no cranial nerve or upper limb deficits. She exhibited a hypotonic hyporreflexic paraparesis with bilateral extensor plantar responses and a sensory level with systematic bilateral proprioceptive errors. MRI of the spine showed increased signal intensity on T2-weighted images in the posterior columns from T11 to L1 levels, without enhancement after IV administration of gadolinium. No significant expansion of the cord was seen. MRI of the brain was normal. Complementary investigation yielded a macrocytic anemia (Hb 11.6 g/dL, VGM 112.0 fL), raising the possibility of a SCD. Vitamin B12 dosing revealed a level of <83 pg/mL. The gastric endoscopic study showed an erythematous gastric atrophy and the histology revealed antral and body evidence of glandular atrophy and chronic inflammation with focal signs of activity. The dosing of the anti-parietal cell antibody was negative. She was submitted to an intramuscular regular program of vitamin B12 replacement. Keywords Subacute combined degeneration, posterior columns, vitamin B12 P.1.061 THE CORRELATION BETWEEN TRANSITIONAL VERTEBRAE TYPES IN REGARDING TO THE LUMBAR DISC AND FACET DEGENERATION IN THE YOUNG MEN POPULATION WITH LOW BACK PAIN M. Apaydin, M. Varer, E. Uluc, O. Oyar Radiology, Izmir Katip Celebi University Ataturk Education and Training Hospital, Izmir, Turkey

S100 OBJECTIVE To investigate the correlation of the types of the congenital lumbosacral transitional vertebrae (LSTV) and degenerative changes in young men population whom are younger than 40 years old. MATERIAL and METHODS The study included 450 out of 2000 patients with LBP with LSTV that lasted longer than 1 month. All cases were screened by standard lomber MRI. Standard protocol of sagittal, and axial T1-weighted and T2weighted spin echo sequences was used. Also coronal images to the lumbosacral area was acquired for evaluation of lumbosacral area. Patients were divided mainly into four groups according to evidence of transitional vertebrae type. LSTV’s were classified in to incomplete or complete as well as uni or bilateral origin. The lumbar disc and facet degeneration as well as anatomical findings were also noted according to the relevant literature. RESULTS While 63 patients were had lumbarization, 387 patients had sacralization. The most frequent sacralization LSTV type was Type I includes unilateral (Ia) (30 %) or bilateral (Ib) (20 %), dysplastic transverse process type II (168/ 387, 37 % , incomplete unilateral (Type II-A) (14 %). We detected 23 % of the patients had incomplete bilateral (Type II-B), 10 % complete unilateral(Type III-A), 12 % complete bilateral (Type III-B), 2 % patient had Type IV transition. The transvers process width did not differ between the types and did not over 19 cm as like in literature. The LSTV types did not have any correlation with with disc herniation but degeneration. Facet arthrosis had found to be relevant with the type 1 of LSTV. CONCLUSION LSTV are found 30 % of the patients. The complaints were higher in the incomplete types. It was known that mechanical imbalance over the LSTV were high due to extra stress to the lumbosacral region to biomechanical response. We can conclude that incomplete LSTV were most likely prone to physicial problems in that region. Congenital lumbosacral transitional vertebra (LSTV) is an anomaly or variation defined as a Keywords Low back pain, MRI, transitional vertebrae P.1.062 MRI FINDINGS IN OCCULT SPINAL DYSRAPHISM M. Varer, M. Apaydin, F. Gelal, E. Uluç, O. Oyar Department of Radiology, Katip Celebi University Izmir Ataturk Education and Training Hospital, Izmir, Turkey Occult spinal dysraphism ( OSD) refers to a group of disorders which occur during the developement of human embryo,resulting with incomplete or incorrect formation of the spinal column, spinal cord and overlying skin. It tends to be overlooked at birth. It is usually diagnosed by cutaneous stigmata or slowly progressing neurological disorders which become apparent later in life. The purpose of this study is to review the MR findings of occult spinal disraphism. Fourteen patients were evaluated with MR imaging, 10 of them being female. The mean age was 18.5. Ten of the patients had dastomatomyelia, 7 of them had syringohydromyelia, 3 had vertebral fusion anomalies, 8 had spina bifida, 6 had tight filum terminale, 3 had lipomas and one of them had dorsal dermal sinus finding. OSD can lead to neurologic, orthopedic and bladder-bowel symptoms. Untreated symptoms can become irreversible. Once diagnosed early surgical correction is mostly preferred. Unfortunately, it is not always

Neuroradiology (2013) 55 (Suppl 1):S15–S159 an obvious diagnosis.Intraspinal anomalies frequently seen are lipomyelomeningocele, the dermal sinus, the tight filum, neuroenteric cyst, diastomatomyelia, the terminal myelocytocele and meningocele. Most of these findings were present in our patient group . In this study we aimed to remind the MR findings in various conditions which have been classified under occult spinal disraphism as a pictorial essay Keywords Diastematomyelia, MRI, spinal dyraphism P.1.063 THE VALUE OF IMAGING IN THE DIAGNOSIS AND TREATMENT OF A TRAUMATIC SACRAL PSEUDOMENINGOCELE: A CASE REPORT A. Moore1, M. Ladino Torres2, F. Rivas Rodriguez3 1 University of Michigan, Department of Radiology, Residency Program, Ann Arbor, MI, USA, 2University of Michigan, Department of Radiology, Division of Pediatric Radiology, Ann Arbor, MI, USA, 3 University of Michigan, Department of Radiology, Division of Neuroradiology, Ann Arbor, MI, USA Traumatic sacral pseudomeningocele as a complication of significant pelvic trauma is a very rare occurrence given the stability of the pelvis in comparison to other parts of the spine. Following pelvic trauma, sacral dural tears with contained accumulations of CSF which are walled off by the proliferating arachnoid and dura are described as pseudomeningoceles, and are most often associated with stretch-type injuries and avulsions of the nerve roots. Here we present a case of traumatic sacral pseudomeningocele following a sports-related injury, and we review the relevance of the imaging workup in confirming the diagnosis and directing nonaggressive therapy. A 44 year old female without any significant past medical history, sustained a fall while ice skating, and presented to the Emergency Room of an outside hospital complaining of sacrococcygeal pain. A CT of the pelvis was performed which demonstrated a displaced sacral fracture with compromise of the anterior and posterior walls of the mid sacral vertebral body. Conservative treatment was recommended at this time. Four days following this trauma, the patient developed positional headaches and presented to the University of Michigan for further investigations. Neurology and neurosurgery services were consulted. MRI of the brain demonstrated multiple imaging findings supporting the diagnosis of intracranial hypotension syndrome. Given the known sacral fracture, the most likely location of a potential dural tear was in the sacral region. A dedicated MRI of the lumbosacral spine was then performed, which redemonstrated the known displaced sacral fracture, as well as the unexpected finding of an open communication between a likely torn thecal sac and the pre-sacral retroperitoneal space. Conventional CT and CT myelogram confirmed a CSF leak with pre-sacral retroperitoneal accumulation of CSF, and the diagnosis of traumatic pseudomeningocele. The treatment of this traumatic pseudomeningocele involved the placement of a lumbar drain, which was left in place for 1 month with the intention of lowering the CSF pressure in order to facilitate the healing of the dural tear. An MRI of the cervical spine documented regression of previously observed signs of intracranial hypotension syndrome. The lumbar drain was removed after 1 month and the patient recovered well. Keywords Pseudomyelomeningocele, trauma, postural headache

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Spine, intervention P.1.064 CLINICAL EVALUATION OF A NOVEL SYSTEM FOR VERTEBRAL AUGMENTATION - CROSSTREES™ POD SYSTEM FOR OSTEOPOROTIC VERTEBRAL COMPRESSION FRACTURES IN ADULT PATIENTS

S101 P.1.065 ARTERIOVENOUS MALFORMATIONS OF THE SPINAL CORD: CHOICE OF CONTEMPORARY ENDOVASCULAR METHOD FOR TREATMENT T. Tissen Burdenko Neurosurgery Institute, Moscow, Russia

A. Rhyne1, M. Lusk2, M. Gillespy3, G. Niedzwiecki4, W. Olan5, H. Yang6, H. Yuan6, P. Yuan7, J. Vandevenne8 1 OrthoCaroline Spine Center, Charlotte, NC, USA, 2NASA Physicians Regional Hospital Pine Ridge, Naples, FI, USA, 3Orthopedic Clinic of Daytona Beach, Daytona Beach, FI, USA, 4Advance Imaging and Interventional Institute, Clearwater, FI, USA, 5George Washington University Hospital, Washington, DC, USA, 6The First Affiliated Hospital of Soochow University, Suzhou, China, 7Long Beach Memorial Center, Memorial Orthopedic Surgical Group, Long Beach, CA, USA, 8 University Hasselt, Ziekenhuis Oost-Limburg, Genk, Belgium

PURPOSE Pain and kyphosis caused by osteoporotic vertebral compression fractures (oVCF) adversely affect quality of life and survival. Kyphoplasty and vertebroplasty have been associated with less than desirable rates of cement extravasation with published rates of 34.5-41 %. Crosstrees Medical, Inc. (Boulder, CO) has developed a percutaneous vertebral augmentation (PVA) system designed to provide vertebral body fracture stabilization while minimizing the risk of cement extravasation. A pivotal US FDA IDE study has been completed. The purpose of this study is to demonstrate safety of the Crosstrees Pod PVA System in the treatment of vertebral body fractures (T4-L5) in the adult spine. METHODS Patients with acute or sub-acute oVCF (T4-L5) were enrolled according to study requirements of the FDA-accepted IDE protocol. Between 2009 and 2012, the Crosstrees Pod device was evaluated prospectively in 135 non-randomized subjects, 80 females and 36 males, aged 74.6 years (range 50–94). Of the 135 patients treated, a total of 161 levels received surgical intervention with PVA. Outcome measures were followed-up at 24 hours; 2 weeks; 1, 3, 6, and 12 months including a physical exam, radiographs and patient questionnaires. Demographic data obtained included age; gender and level of fracture(s). Technical measures included intraoperative device related adverse events, PMMA extravasation, and reduction of pain evaluated by VAS scale. Secondary outcome measures included vertebral body morphology, SF-12, ODI, patient satisfaction, and late fracture. RESULTS Initial assessment of outcomes is reported for 116 patients at the primary outcome evaluation of 6 months follow up. Clinically significant improvement in pain relief was reported in 93.8 % of patients. Extravasation reported by the radiographic core laboratory occurred in of 18/115 subjects treated, or 15.7 %, all which were reported as asymptomatic. Investigator reported extravasation was noted in 8/118 subjects, or 6.9 %. New clinical fractures were reported in 7.9 % of subjects. No device related adverse device events or complications were reported. CONCLUSIONS Extravasation rates for the Crosstrees Pod PVA System are reduced from those previously reported. Primary outcome measures meet study success criteria. The Crosstrees PVA Pod may offer an opportunity for improved control of PMMA delivery to the vertebra. Keywords Vertebral augmentation, cement leakage, device

The purpose is to determine the optimal endovascular method and its features in the treatment of arteriovenous malformations (AVM) of the spinal cord. METHODS 1200 patients with AVM of the spinal cord were treated in period over 30 years. Among them were men 69 %, women 31 %, including 315 children.The endovascular occlusions of afferent AVM`s vessels using the different methods from the first balloon-occlusion method by F. Serbinenko to with the coils. RESULTS Occlusion of spinal afferent vessels and AVM‘s stroma was mainly performed by using PVA-emboli, glue Hystoacryl and coils. Dural arteriovenous fistulae (DAVF) localized on the posterior spinal cord surface had great extension in veins and slow blood velocity. Endovascular occlusion for this type of DAVF consists in direct injection of the glue into the vessel and intercostal artery. When dealing with endovascular occlusion of the AVM supplied by the artery of Adamkiewicz, it is necessary first to extinct accessory sources of blood supply and only then if possible to extinct an aneurysm from the Adamkiewicz artery system by using glue or coils. The technique used resulted in outcome improvement in 90 % of cases, 7 % of patients revealed no dynamics, and 3 % showed neurological impairment. CONCLUSION The choice of using a method of endovascular occlusion should be based on thorough analysis of spinal angiography and MRI data, haemodynamic characteristics of the AVM and DAVF spinal cord. Keywords AVM, spinal cord, endovascular treatment P.1.066 RADIOFREQUENCY ABLATION OF SPINAL OSTEOID OSTEOMA AND OSTEOBLASTOMA – TECHNICAL ADVANCES FOR PROTECTING ADJACENT NEURAL ELEMENTS AND CLINICAL SUCCESS RATES M. Weber1, S.D. Sprengel1, G. Omlor2, B. Lehner2, H.U. Kauczor1, C. Rehnitz1 1

University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg, Germany, 2University Hospital Heidelberg, Department of Orthopaedic Surgery, Heidelberg, Germany PURPOSE 10 % of all osteoid osteomas (OO) are located in the spine. OO with a size of more than 15 mm is denominated osteoblastoma (OB). Computed tomography (CT)-guided radiofrequency ablation (RFA) is the accepted treatment for OO in the extremities, but is limited in spinal applications due to the risk of thermal damage of adjacent neurovascular structures. Thus, our purpose was to assess the clinical success of RFA of spinal OO using dedicated techniques of thermal protection.

S102 METHODS Seven patients with spinal OO and 2 with spinal OB (median age, 24 years) were treated with CT-guided RFA over 400 s with 90° Celsius. Diagnosis was proven by multi-detector CT, magnetic resonance imaging, scintigraphic bone scans, and in OB using CT-guided biopsy. Procedural techniques included three-dimensional CT-guided access planning in all cases, two overlapping RFA needle positions within the OB nidus, and thermal protection by epidural air insufflation (5 ml) in case of missing cortical layer of the tumour with regard to the neuroforamen or the spinal canal and less than 10 mm distance to neural elements (n=2). Long-term success was assessed using a questionnaire including visual analogue scales (VAS) regarding the effect of RFA on severity of pain and limitations in daily activities (0–10, with 0=no pain/limitation up to 10=maximum pain/limitation). RESULTS Median follow-up time was 27 months. Technical and clinical success rate was 9/9 (100 %) of all patients. No complications were observed. The clinical outcome measured with the VAS pain score did not differ between spinal OB and OO. After RFA, the pain usually resolved within a week and all patients had a clear and persistent pain reduction (p < 0.001). The mean VAS score for all patients decreased from 8.33±1.53 to 1.33±1.15 for severity of pain and from 5.00±5.00 to 1.67±2.89 for limitations in daily activities. CONCLUSIONS RFA is an efficient method to treat spinal OO and OB and thus should be regarded as first line therapy. Using thermal protection methods, even OO adjacent to nerve roots or the spinal cord can be treated safely and with very good clinical success, so that open surgical excision of spinal OO will be less needed. Keywords Spinal osteoid osteoma, radiofrequency ablation, protection of neural elements

Stroke and cerebrovascular disease, diagnostic P.1.067 P H A S E - C O N T R A S T S Y N C H R O T R O N X - R AY MICROTOMOGRAPHY OF CEREBRAL PROTECTION DEVICE RETRIEVED AFTER CAROTID ARTERY STENTING S. Youn1, H. Kim1, H. Lee2, J. Lee2, H. Kim1 Catholic University of Daegu, Daegu, South Korea, 2Kyungpook National University, Daegu, South Korea

1

PURPOSE The phase-contrast synchrotron x-ray microtomography (pcSyncX) has visualized the microstructures of biologic specimens due to highly coherent X-ray beam, but it had never been used for evaluation of embolic debris captured on cerebral protection device (CPD). The purpose of this study was to demonstrate the feasility of pcSyncX as tools for evaluating the embolic debris during carotid artery stenting (CAS). METHODS Five patients (4 males; range, 67–77 years) with severe carotid artery stenosis underwent CAS. The retrieved cerebral protection device (CPD) was placed in front of the synchrotron radiation. A total of 1,000 projection images of pcSyncX were obtained by rotating CPD through 180°. An x-ray shadow of a CPD was converted into a visual image by the scintillator. After microtomographic reconstruction, the three-dimensionally reconstructed images were further segmented into the embolic debris and CPD. Total volume of emboli was calculated by summing up each volume per scanning level. The membrane pore covered by emboli was counted seen from outer surface, and the percentage of covered area was calculated. RESULTS Embolic debris were clearly demonstrated not only at the inner surface and within pore but also outer surface of CPD. The mean total volume

Neuroradiology (2013) 55 (Suppl 1):S15–S159 of embolic debris was 0.538 x 10-6 mm3 (range, 0.225–0.965 x 10– 6 mm3). The average 61.5 % of them were located at apical one third of CPD. The average 20.8 % of the pore area were covered by the debris. CONCLUSION The pcSyncX allow us to visualize the microscale appearance of embolic debris in relation to the pore of CPD. By using pcSyncX, we can measure the volume of embolic loads either total or as per the location along the axis. The pcSyncX would eventually help to improve the design of CPD or to modify procedural steps to reduce complications. Keywords Synchrotron x-ray, embolic debris, cerebral protection device P.1.068 THE RELATIONSHIP BETWEEN MEAN PLATELET VOLUME AND ATTENUATION VALUES OF ACUTE INTRACEREBRAL HAEMATOMAS ON COMPUTED TOMOGRAPHY SCANS E. Unlu1, S. Ulu2, E. Kacar1, E. Yilmaz3, S. Ozdinc4, E. Dogan Baki5, H. Uzel Tas6, A. Haktanir1 1

Afyon Kocatepe University Faculty of Medicine, Department of Radiology, Afyonkarahisar, Turkey, 2Afyon Kocatepe University Faculty of Medicine, Department of Internal Medicine, Afyonkarahisar, Turkey, 3 Afyon Kocatepe University Faculty of Medicine, Afyonkarahisar, Turkey, 4Afyon Kocatepe University Faculty of Medicine, Department of Emergency Medicine, Afyonkarahisar, Turkey, 5Afyon Kocatepe University Faculty of Medicine, Department of Anesthesiology and Reanimation, Afyonkarahisar, Turkey, 6Afyon Kocatepe University Faculty of Medicine, Department of Public Health, Afyonkarahisar, Turkey OBJECTIVE The relationship between the computed tomography (CT) attenuation of blood and hemoglobin levels were shown before. However, little is known about the effect of platelet function disorders on attenuation values of haematomas. We aimed to investigate the relationship between mean platelet volume (MPV) and the attenuation values of haematomas on unenhanced CT scans. MATERIALS AND METHODS The study was included 77 patients who had undergone unenhanced CT scan within the first 24 hours of the intracranial haemorrhages (ICH ) and had peripheral blood examination. The patients who have normal hemoglobin values were included in the study to minimize the effect of hemoglobin on the CT attenuation of blood. We measured Hounsfield Units in a region of interest within the intracranial haematomas and correlated these data with blood parameters in male and female patients aged 1 to 83 years. Pearson and Spearman correlation analysis were used to assess the relationships between measured CT attenuation of haematomas and blood parameters. RESULTS The attenuation values of the haematomas was directly correlated with MPV levels (p=0.03). In addition, there was no significant correlation between the density of haematoma and hemoglobin, hemotocrite, red cell Distrubition Width (RDW), platelet count (PC) and platelet distribution width (PDW). CONCLUSION In conclusion, MPV is a significant factor that effects the attenuation value of haematoma on CT scan beside hemoglobin levels. Keywords Intracranial haemorrhage, computed tomography, mean platelet volume P.1.069 PREVALENCE OF SMALLVESSEL DISEASES IN ASIAN PATIENTS WITH SPONTANEOUS INTRACRANIAL HEMORRHAGE S.W. Chang1, Y.H. Tsai1, H.H. Weng1, M.H. Lee2 1

Department of Radiology, Chang Gung Memorial Hospital, Chiayi, Taiwan, 2Department of Neurosurgery, Chang Gung Memorial Hospital, Chiayi, Taiwan

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE Small vessel disease, including hypertensive arteriopathy and cerebral amyloid angiopathy is an important cause of spontaneous intracerebral haemorrhage (ICH). There are four neuromiaging makers of small vessel disease that can be observed by MRI: 1) Enlarged perivascular spaces (EPVS), 2) Periventricular white matter hyperintensities or leukoaraiosis (LA) and 3) lacunar infarctions. Recent studies have showed the high prevalence of these factors among ICH patients in Western countries. These markers have also been reported to be associated with functional outcome after ICH. However, the prevalence and etiology of ICH in Asian are different from that in Caucasian race. To know the racial differences of small vessel disease may help us to understand the association between small vessel disease and ICH. METHODS Fifty patients with first-ever spontaneous ICH were enrolled in this study. MRI scans were performed within the first week after stroke onset. Clinical information was obtained using standardized forms. EPVS, LA and old lacunar infarctions were rated using validated forms. The EPVS is identified on T2-weighted imaging and is defined as a small and sharply delineated structure of cerebrospinal fluid intensity that follows the orientation of the perforating vessels and perpendicular to the brain surface. The LA is identified on Fluid-attenuated inversion recovery imaging. RESULTS Among ICH patients, the prevalence of EPVS is 80 % for basal ganglion and 48 % for centrum semiovale. 86 % of patient suffered from LA in periventricular regions and 44 % suffered from LA in deep white matter matter. 38 % patients had lacunar infarction in cortical and subcortical regions, 42 % patients had lacunar infarction in deep grey matter and 8 % patients had lacunar infarction in brainstem. CONCLUSIONS The prevalence of small vessel disease identified by MRI is different between Asian and Caucasian race. In compared with the prevalence reported in previous literature of Caucasian ICH patients, Our results showed Asian patients had higher incidences of concurrent lacunar infarctions (46 % versus 26 %), lower incidence of EPVS (82 % versus around 100 %) and similar incidence of LA (86 % versus around 85 %). Further investigation of these racial differences may improve our understanding of pathophysiology associating ICH. Keywords Hemorrhage, small vessel disease, asian

S103 APPROACH/METHODS 1. We explain DTI techniques, postprocessing, and tractography as well as how to optimize the protocol for AIS. 2. We use cases of acute, subacute, and chronic strokes to address the potential role of anisotropic parameters as a biomarker of stroke age. 3. We discuss methods of analyzing quantitative and qualitative data (Olea Medical, Sphere, La Ciotat, France) from DTI about the integrity of functional WMT to predict clinical outcome after AIS. 4. We highlight the role of anisotropic indexes as biomarkers of strokerelated damage and the potential value of lesion mapping techniques. FINDINGS/DISCUSSION Water diffusion in brain tissue is affected by barriers to translational motion like cell membranes and white matter tracts. Anisotropic water diffusion can be specified using several indices (e.g., eigenvalues (λ1, λ2, λ3), fractional anisotropy (FA), mean diffusivity). Diffusion anisotropy increases in the first hours after AIS. Thus, DTI could be useful in patients in whom the onset is unknown (up to 25 %) and in the clinical evaluation of new treatments. Furthermore, stroke is the commonest cause of disability in adults in many countries. Accurate early prediction of outcome would enable realistic goalsetting and efficient resource allocation by clinicians and patients. Damage to the posterior limb of the internal capsule is an early imaging predictor of poor motor outcome. Lower FA values on corticospinal tract (CST) distal to the infarct are associated with worse motor recovery. SUMMARY DTT should be incorporated into MRI protocols for AIS because it could help determine stroke age. Damage to specific WMT (e.g., CST) can help predict clinical outcome. A better understanding of predictors of outcome would help in selecting clinically meaningful outcome measures for future studies. Keywords Diffusion tensor imaging, stroke, outcome P.1.071 WALL ENHANCEMENT OF THE CEREBRAL ARTERYANEURYSMS AFTER GADOLINIUM INJECTION: EVALUATION BY MRI USING MSDE-3D-TSE SEQUENCE S. Nagahata1, M. Nagahata1, M. Obara2, Y. Minagawa3, S. Sato3, R. Kondo4, S. Saito4, T. Kayama5 1

P.1.070 DIFFUSION TENSOR IMAGING IN ACUTE STROKE: CLINICAL APPLICATIONS FROM DETERMINING LESION AGE TO PREDICTING OUTCOME J. Puig1, G. Blasco1, J. Daunis-I-Estadella2, M. Castellanos3, J. Serena3, J. Figueras4, S. Pedraza1 1

Department of Radiology (IDI), Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain, 2Department of Computer Science, Applied Mathematics and Statistics, University of Girona, Girona, Spain, 3Department of Neurology, Girona Biomedical Research Institute (IDIBGI), Hospital Universitari Dr Josep Trueta, Girona, Spain; 4Department of Rehabilitation, Hospital Universitari de Girona Dr Josep Trueta, Girona, Spain PURPOSE Diffusion tensor imaging (DTI) provides information on the microstructural status of brain tissue by quantifying anisotropic indexes that reflect inherent biophysical properties of tissue structure and determining the direction of the anisotropic diffusion of the white matter tracts (WMT). We show how determining the anisotropy profile in the infarcted areas and assessing the integrity of specific WMT by tractography can improve the management of acute ischemic stroke (AIS) patients.

Yamagata City Hospital SAISEIKAN Stroke Center, Department of Diagnostic and Interventional Neuroradiology, Yamagata, Japan, 2Philips Electronics Japan, Ltd., Tokyo, Japan, 3Yamagata City Hospital SAISEIKAN, Department of Radiology, Yamagata, Japan, 4Yamagata City Hospital SAISEIKAN Stroke Center-Department of Neurosurgery, Yamagata, Japan, 5Yamagata University Faculty of Medicine, Department of Neurosurgery, Yamagata, Japan PURPOSE Motion sensitized driven equilibrium (MSDE) method can reduce the intraluminal blood signal, even in the post-contrast MR imaging. In this paper, we investigate the wall enhancement of cerebral aneurysms after injection of gadolinium using MSDE3D-TSE sequence. METHODS We retrospectively reviewed post-contrast MSDE-3D-TSE images of consecutive 95 saccular aneurysms in 80 patients (43 patients with SAH, 37 patients with unruptured aneurysms) from September 2011 to December 2012. MSDE-3D-TSE sequence was performed in three directions (axial, coronal, and sagittal) targeting to the aneurysm with a high resolution protocol consisting of T1w 3D-TSE sequence, TR/TE 425/12.8, 50 sections, 0.72x0.95x0.70 mm voxel size, and a 384x342imaging matrix on a 3 T Achieva scanner (Philips). Pre-operative MR examination was performed under general anesthesia in all of the 43 patients with SAH. In this study, objective aneurysms we investigated were 43 ruptured (surgically verified) aneurysms and 52 unruptured aneurysms. We evaluated the wall enhancement of each aneurysm on

S104 MSDE-3D-TSE images. All images were analyzed by experienced neuroradiologist and neurosurgeons in consensus and classified as strong wall enhancement (equal to choroid plexus), faint enhancement (increased wall signal than pre-contrast scan), and no enhancement. In this study, we excluded fusiform aneurysms and dissecting aneurysms. RESULTS Strong enhancement of the aneurysmal wall was observed in 72 % of the ruptured aneurysms and 6 % of the unruptured aneurysms. No enhancement was observed in 79 % of the unruptured aneurysms and 5 % of the ruptured ones. Post-contrast MSDE-3D-TSE images demonstrated sensitivity of 72.1 % and specificity of 94.2 % for differentiation ruptured aneurysms from unruptured ones. CONCLUSION We could evaluate the wall enhancement of cerebral aneurysms using MSDE-3D-TSE sequence. Strong enhancement of the aneurysmal wall may be indicative of ruptured condition. Keywords MRI, gadolinium, cerebral artery aneurysm P.1.072 HIV-RELATED RARE DIFFUSE ANEURYSMAL CEREBRAL VASCULOPATHY: FOUR NEW CASES AND REVIEW OF THE LITERATURE B. Law-Ye1, R. Richard1, F. Clarencon2, R. Blanc3, C. Jourdan4, D. Siahou1, C. Wattel1, D. Safa1, A. Felter1, R. Carlier1 1 Hospital Raymond Poincaré, Department of Radiology, Garches, France, 2Hospital Pitié-Salpêtrière, Department of Neuroradiology, Paris, France, 3Alfred de Rothschild Foundation, Department of Neuroradiology, Paris, France, 4Hospital Raymond Poincaré, Department of Reeducation, Garches, France PURPOSES OF OUR STUDY - To present four new cases of HIV-related cerebral vasculopathy in a rare form of diffuse proximal fusiform aneurysms with an emphasis on imaging features - To discuss physiopathology and relation to length of evolution of the infection - To show main differential diagnosis - To discuss management of these vascular lesions METHODS Between 2006 and 2013, 4 patients were adresses in 3 different centers for neurologic symptoms (repeated ischemic strokes, epilepsy, incidental discovery). Brain vascular exams were performed for each patient (angioTDM, angioMR or digital substraction angiography) and showed diffuse fusiform aneuryms of the arteries of Willis polygon. Review of the literature. RESULTS All 4 patients were female patients. HIV infection was acquired at an adult age in 3 patients and was neonatal in one patient. Typical vascular lesion was a fusiform ectasy of the carotid terminus extending to A1 and M1 segments of anterior and middle cerebral arteries (4/4). In one patient, there was involvement of the posterior cerebral circulation. Minimum period between infection and diagnosis of the vasculitis was 7 years. Treatment was medical in most cases; in one patient, a symptomatic compression of the brainstem required an endovascular treatment consisting of an occlusion of the right vertebral artery . In data of the literature, this type of HIV-related vasculopathies are rare. A systematic review of the literature published in 2010 gathered 11 cases and one previously unpublished case. Physiopathology is complex with a very important inflammation of the artery wall.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Risk factors may be a high viral load and low rate of lymphocytes CD4. Frequent ischemic or hemorrhagic complications are found. Differential diagnosis are not numerous, and include atherosclerosis as well as a case of chronic EBV meningeal infection in a 12-year-old child. CONCLUSION HIV-related diffuse aneurysmal cerebral vasculopathy is a rare yet previously-reported entity. It has been reported in HIV-infected children for more than 20 years and have only been described recently in adult patients with very few cases published. Physiopathology is complex, characterized by an important inflammation of the artery wall and it may be related to high viral load, low rate of TCD4 cells and length of evolution of the infection. It is noteworthy that management of this pathology can require interventional neuroradiology. Keywords HIV, diffuse aneurysms, vasculitis P.1.073 BRAIN INJURY AFTER CARDIOPULMONARY ARREST AND ITS ASSESSMENT WITH DIFFUSION-WEIGHTED MRI Y. Ihn, W. Jung St.Vincent's Hospital, Suwon, South Korea PURPOSE The prognosis of comatose survivors is determined by clinical examination. Early laboratory indicators of poor prognosis (such a evoked potentials) have low sensitivity. To characterize the frequency and pattern of diffusion weighted imaging (DWI) abnormalities detected as part of brain MRI and their association with short-term neurologic outcomes in patients successfully resuscitated after cardiopulmonary arrest (CPA). MATERIALS AND METHODS We retrospectively analyzed a case series of patients who experienced cardiopulmonary arrest between March 1st 2011, and Feb. 28, 2013 at our hospital. Eligible patient required treatment by the Code Blue team and had at least 1 DWI study before discharge or death. Two neuroradiologists jointly classified DWI abnormalities by anatomic location RESULTS Ten patients showed diffuse signal abnormalities, predominantly in the cerebellum (n=10 ), the frontal and parietal cortices (n=8 ), the caudate nucleus ( n=9), and hippocampus ( n=8). Cortical areas (global and regional) were the most common sites of restricted diffusion. None of the patients with abnormal cortical structures on DWI MR images recovered beyond a severely disabled state. CONCLUSION Diffusion weighted imaging in comatose survivors may parallel the pathologic findings in severe anoxic-ischemic injury, and extensive abnormalities may indicate little to no prospects for recovery. Keywords Cardiac arrest, diffusion weighted imaging, magnetic resonance imaging P.1.074 THE VALIDATION OF CT BRAIN PERFUSION IN PATIENTS WITH ACUTE ISCHEMIC STROKE B. Georgievski-Brkic1, D. Kozic2, J. Ostojic3, M. Radovic-Stefanovic4, G. Milenkovic1, P. Nikic5 1

Stroke Hospital Sveti Sava, Radiology Department, Belgrade, Serbia, Institution for Oncology Vojvodina , Radiology Department, Sremska Kamenica, Serbia, 3Clinical Centar of Vojvodina, Radiology Department, Novi Sad, Serbia, 4Clinical Centar Bezanijska Kosa, Radiology Department, Belgrade, Serbia, 5Stroke Hospital Sveti Sava, Neurology Department, Belgrade, Serbia

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Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE CT perfusion (CTP) is advanced technique which is applicable in acute stroke patients. CTP accurately shows localization and size of infarct, selects candidates for thrombolytic therapy (rTPA) by differentiating core infarct and ischemic penumbra, and approximates final size of infarct. METHODS In Stroke Hospital „ Sveti Sava“ in Belgrade, from March 2008 to April 2013, 130 patients were included in this study. They underwent unenhanced CT and CTP. All patients presented with symptoms of acute brain stroke within 6 hours of onset. First, we performed unenhanced CT brain for exclusion of hemorrhage. After that, we examined them by CTP deconvolution technique, using i.v. contrast application in the amount of 40 ml, and dynamic scanning specific brain region range 2 cm. CTP was often performed at basal ganglia’s level, but other level scanning was suggested by neurologist. CBV, CBF i MTT maps were calculated. After 24 h, control brain CT was made. Inclusion criteria was improving ischemic lesion in CTP. Exclusion criteria were: strong motion artifacts and false negative cases, when ischemia was located outside of CTP imaging. We divided patients in two groups. The experimental group (N=100) received intravenous rTPA and control group (N=30) did not received rTPA. In all type of images (CBV, CBF i MTT and follow up CT) we measured areas of lesion, expressed in square of millimeters. We used CBV/CBF mismatch for evaluation of penumbra and calculate percent of penumbra and percent of preserving predicting penumbra. RESULTS There were statistically significant differences between experimental and control group, F (1,128) =25.46, p< .01, R2= .17, in the size of deficit in CBV map and infarct size in follow up CT. In experimental group the difference in size of CBV deficit and final size of infarct is smaller (M= 68.21, SD=290.16) than in control group (M=504.00, SD= 687.30). In experimental group in 88 % patients were achieved salvage of predicted penumbra, but only in 12 % patients in control group.Between experimental and control group there were significant difference in percent of preserving predicted penumbra, x2 (N= 130,1)=5.52, p<.05. CONCLUSION Lesions on CTP are highly predictive of final infarct size, especially in patients who receiving intravenous rTPA. Keywords CT perfusion, penumbra, thrombolytic therapy P.1.075 NEUROIMAGING AND PATHOLOGICAL CORRELATES OF THE “IOWA” MUTATION – THE FIRST REPORTED IRISH FAMILY L. Galvin1, R. Grech1, A. Chalissery2, D. Mcweeney1, L. Costello2, J. Moroney2, P. Brennan1, J. Thornton1, A. O'Hare1, M. Farrell3, S. Looby1 1

Beaumont Hospital, Department of Neuroradiology, Dublin, Ireland, Beaumont Hospital, Department of Neurology, Dublin, Ireland, 3Beaumont Hospital, Department of Neuropathology, Dublin, Ireland

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PURPOSE To provide the first reported description of the neuroimaging features and pathological findings of the so-called “Iowa” mutation of amyloid precursor protein (APP) in an Irish family. METHODS The family pedigree over four generations is summarised. The neuroimaging of four family members is described. Histopathogical correlation was available in two patients. RESULTS There was a strong family history of both dementia and anencephaly. Four related patients presented to our institution over a fourteen year period. Three patients showed signs of early Alzheimer-type dementia

S105 and two of these presented with acute lobar haemorrhage. All three demonstrated bilateral, symmetric cortically-based calcification in a predominantly parieto-occipital distribution, with varying degrees of underlying chronic small vessel disease. Extensive intracerebral amyloid deposition was histologically confirmed in one patient with cortical calcification, who subsequently died of catastrophic haemorrhage following brain biopsy. For this reason biopsy was avoided in her cousin, who subsequently had serological confirmation of the APP gene mutation. Her demented father had an almost identical pattern of cortical calcification on computed tomography. The fourth patient had an oligodendroglioma detected on screening MRI- histological examination revealed perivascular amyloid protein deposition within the tumour. CONCLUSION The autosomal dominant “Iowa” gene mutation of APP, although rare, is often associated with a characteristic and almost pathognomonic pattern of symmetric, cortical calcification on brain imaging. Due to the high association of APP mutation with both early dementia and intracerebral haemorrhage, timely diagnosis is paramount both to implement important therapeutic measures and for genetic counselling of family members. Keywords Amyloid, angiopathy, iowa P.1.076 IMPROVED 3D PHASE CONTRASTANGIOGRAPHIC MAGNETIC RESONANCE VENOGRAPHY OF THE BRAIN: INITIAL CLINICAL EXPERIENCE IN 25 PATIENTS N. Campeau, A. Patton Mayo Clinic, Rochester, MN, USA PURPOSE To describe our initial experience performing magnetic resonance venography (MRV) of the brain using a new commercially available 3D phase contrast (PC) angiographic technique which does not require intravenous gadolinium administration, and has improved features that permit acquisition of high resolution angiographic images with excellent background suppression and short scan time. METHODS This 3D phase contrast technique differs from conventional methods by use of parallel imaging; optimized k-space sampling (elliptical centric view ordering/corner cutting); phase cycling of excitation RF to spoil signal from tissue with longer T2; partial Fourier acquisition, and zerofilling. Complex difference (not phase difference) reconstruction is used so there is no need for phase unwrapping. Specific protocols for performing 3D PC MRV of the brain were optimized with respect to acquisition volume orientation, matrix size, velocity encoding gradient amplitude (VENC), and use of saturation bands to suppress arterial flow. Comparison with corresponding available 3D-TOF, 2D-TOF and gadolinium enhanced MRV techniques are provided in 25 clinical studies. The PC-MRV images were evaluated for accuracy in detection of vascular stenosis, as well as image quality and artifacts. RESULTS Ages ranged from newborns to 86 years. 3D PC MRV acquisition was successfully obtained in all 25 patients. The 3D PC MRV suffered from signal dropout compared to gadolinium enhanced techniques, but much less so than comparable 2D TOF MRV acquisitions. Saturation effects were minimized by varying the volume orientation and artifacts were more marked with axial acquisition compared to sagittal or coronal directions. Complex difference reconstruction eliminated the typical “aliasing” artifact seen with phase difference reconstruction, and allowed for a broader selection of velocity encoding gradients. CONCLUSION Bolus gadolinium MRV remains the gold standard, however 3D PC MRV is a superior alternative to 2D TOF MRV of the brain, with less

S106 saturation dropout and improved visualization of cortical veins. The 3D PC MRV technique is robust and works well for all ages ranging from neonate to octogenarian, and is recommended for imaging patients who cannot tolerate gadolinium because of allergy or renal insufficiency. Keywords MRV, phase contrast, dural venous sinus P.1.077 CT VENOGRAPHY IN THE EVALUATION OF CEREBRAL VENOUS SINUS THROMBOSIS J. Avsenik1, B. Jancheva2, J. Pretnar Oblak2, K. Surlan Popovic1 1

Institute of Radiology, University Medical Centre, Ljubljana, Slovenia, Department of Neurology, University Medical Centre, Ljubljana, Slovenia PURPOSE The aim of our study was to determine the role of computed tomography venography (CTV) in the evaluation of patients with suspected cerebral venous sinus thrombosis (CVST). METHODS We reviewed clinical data and imaging studies of 32 patients who were admitted to neurological emergency department with clinical signs of CVST from October 2011 to April 2013. All patients underwent nonenhanced computed tomography scan (CT) and CTV. Clinical signs and symptoms, patients' risk factors, laboratory results and radiological studies were retrospectively analyzed. RESULTS CVST group comprised of 12 subjects (9 women) in whom the diagnosis of CVST was radiologically confirmed. The control group comprised of 20 subjects (14 women) in whom the diagnosis was rejected. The CVST group and the control group did not differ in age (37.7 vs 46.3 y) and they had similar presenting symptoms, the most common being headache (n=9 vs. 16), followed by vomiting (n=6 vs. 4). History of recent abortion, pregnancy or puerperium was confirmed in 1 CVST patient and 2 controls, while the use of oral contraceptives was confirmed in 4 CVST patients. One CVST patient had normal D-dimer values and the initial non-enhanced CT scan was normal in 5 CVST patients. The most common site of thrombosis was transverse sinus (n=9; 5 on the right side), followed by superior saggital sinus (n=6) and right sigmoid sinus (n=5). Alternative diagnosis was established in 15 control subjects, namely sinusitis (n = 7), followed by intracranial haemorrhage (n=6). One case of supratentorial meningeoma and one case of PRES syndrome were diagnosed by initial CT scan and were later confirmed by MRI. CONCLUSIONS Transverse sinus is the frequent site of CVST, accounting for 75 % of our cases. However, a negative non-enhanced CT scan on admission or a normal D-dimer value do not exclude the presence of CVST. Therefore, appropriate use of other imaging modalities is mandatory, whenever there is a high degree of clinical suspicion. CTV is a good alternative to MRI for the diagnosis of CVST and should be interpreted together with clinical and laboratory data. Keywords Cerebral venous thrombosis, cerebral venography, computed tomography

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P.1.078 POSSIBILITIES OF MSCT ANGIOGRAPHY IN DETECTION AND CHARACTERIZATION OF DISTAL INTRACRANIAL ANEURYSM REPORT OF SEVEN CASES AND REVIEW OF LITERATURE V. Vasiljevic1, S. Milosevic Medenica2 1

Dptm. of Neuroradiology, Center of Radiology and MR, Clinical Center of Serbia, Belgrade, Serbia, 2Dptm. of Neuroradiology, Center of Radiology and MR, Clinical Center of Serbia, Belgrade, Serbia

Neuroradiology (2013) 55 (Suppl 1):S15–S159 INTRODUCTION Distal intracranial aneurysms are extremely rare and occur in 0,3-9 % of all brain aneurysms. In previous years cerebral DSA was method of choice for diagnosing all vascular pathological changes, distal intracranial aneurysms included. Today, the MCTA or MRA are increasingly used for detection of intracranial vascular pathological changes. MATERIALS AND METHODS From November 2012 to April 2013 we performed 397 MSCTA in our institution, out of which in 7 patients (6 females and 1 male) distal intracranial aneurysms were diagnosed. The patients’ age ranged from 33 to 71 years. Case 1. Woman (63) , came for severe long lasting headaches. MCTA detected a distal aneurysm of temporal branch of the right ACM. Diagnosis was confirmed by DSA. The aneurysm was treated by coiling. Case 2. Woman (71), came for examination because of headaches and high blood pressure. MSCTA detected an aneurysm on distal part of the left PICA. DSA confirmed diagnosis, but it was decided not to proceed with any treatment due to bad general condition. Case 3. Woman (66) came for left eyelid drooping. MSCTA showed distal aneurysm of the left ACP branch. No indication for neurosurgical or endovascular cure was made. Case 4. Man (42) was sent to MSCTA due to occasional headaches. MSCTA detected an aneurysm on the occipital branch of the left ACP. Patient underwent DSA and endovascular treatment.. Case 5. Female (33), was admitted to the Neurosurgery because of the SAH . MSCTA showed saccular aneurysm on the distal segment of the left ACP. Patient underwent DSA and endovascular treatment. Case 6. Female (57) was sent to MSCTA due to persistent headaches. The examination showed a distal aneurysm on the distal part of the ACA. She underwent endovascular treatment. Case 7. Female (57) was admitted to Neurosurgery because of the SAH. MSCTA found an aneurysm on the distal segment of the ACA with frontal intracerebral hematoma. DSA was done followed by endovascular treatment. CONCLUSION The MSCTA on 128 - sliced CT apparatus is reliable method for fast detection and therapy planning for intracranial aneurysms. Keywords Cerebral aneurysms, MSCT angiography, distal aneurysms P.1.079 WORKUP OF SUSPECTED DELAYED CEREBRAL ISCHEMIA IN SUBARACHNOID HEMORRHAGE: A DECISION ANALYSIS S. Rawal1, C. Barnett Tapia2, A.A. John-Baptiste3, H.H. Thein4, T. Krings1 1 Toronto Western Hospital, University of Toronto, Division of Neuroradiology, Department of Medical Imaging, Toronto, Canada, 2Toronto General Hospital, University of Toronto, Department of Neurology, Toronto, Canada, 3Women's College Research Institute, Women's College Hospital, University of Toronto, Toronto, Canada, 4Dalla Lana School of Public Health, University of Toronto, Toronto, Canada

PURPOSE Delayed cerebral ischemia (DCI) is a severe complication of subarachnoid hemorrhage (SAH), originally thought to be the result of vasospasm. Emerging literature has questioned the causality of this relationship; however, many proposed therapeutic strategies for DCI remain targeted at patients with vasospasm. This study was performed to assess whether treatment for suspected DCI on the basis of vasospasm detection would improve outcomes relative to treating all symptomatic patients.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS A decision analysis was performed using a Markov model with a lifetime horizon. The base case was assumed to be a 55-year-old patient following SAH with a single, treated aneurysm, symptomatic for DCI. Strategies considered were to either undergo diagnostic testing for vasospasm - including digital subtraction angiography (DSA), computed tomography angiography (CTA), or computed tomography perfusion (CTP) - where only those testing positive for vasospasm were treated, or to treat immediately. Treatment consisted of induced hypertension as per current practice guidelines. Outcomes assessed were survival in terms of life-years and quality-adjusted life-years (QALYs). RESULTS The dominating strategies were DSA and 'Treat all' by very minor incremental differences in QALYs over CTA and CTP (QALYs: DSA 9.787; Treat all - 9.785; CTA - 9.71; CTP - 9.68). The model was robust over clinically plausible ranges for the included variables. Major drivers of the model pertained to the adverse effects of DSA and treatment, as well as the sensitivity of DSA. However, altering these variables over wide ranges did not result in significant absolute differences in QALYs. CONCLUSIONS For prevention of infarction and improvement of outcome in DCI, treating on the basis of vasospasm detection is not significantly better than treating all symptomatic patients. This supports a growing body of literature suggesting that vasospasm may not be the most appropriate therapeutic target in patients with suspected DCI. Keywords Delayed cerebral ischemia, vasospasm, decision analysis P.1.080 HEMODYNAMIC ALTERATIONS IN CEREBRAL BLOOD VESSELS AFTER CAROTID ARTERY REVASCULARISATION: QUANTITATIVE ANALYSIS USING 2D PHASE-CONTRAST MRI S. Youn1, H. Kim1, Y. Doh1, J. Doh1, J. Lee2 1

Catholic University of Daegu, Daegu, South Korea, 2Kyungpook National University, Daegu, South Korea OBJECTIVES This study was conducted to evaluate the effect of revascularisation, whether revascularisation improves total cerebral blood flow volume (FVTCBF), and how cerebral veins would respond to altered FVTCBF. METHODS The 39 carotid artery stenoses in 37 patients who underwent revascularisation including 32 stentings and 7 endarterectomies were included in this prospective study. From the 2-dimensional phase-contrast (2D-PC) MRI acquired before and after revascularisation, the flow volumes (FVs) of the arteries and veins were compared using paired t-test. The relationships between these parameters were correlated using Pearson’s correlation. RESULTS The mean FV in the treated carotid artery (proportion of treated artery among total FV) increased from 162.06 mL/min (25.80 %) to 267.71 mL/min (37.21 %; P<0.001). Revascularisation increased the FVTCBF of patients from 638.66 mL/min to 716.72 mL/min (P<0.001). The FV of the internal jugular veins, superior sagittal and straight sinuses (FVSS+SSS), and transverse sinuses increased after revascularisation (P<0.05). Positive relationships were shown between the FVTCBF and the FVSS+SSS (r=0.584–0.741, P<0.001). CONCLUSIONS Revascularisation improves the FVTCBF by increasing the FV in the treated carotid artery. The venous drainages are closely linked to FVTCBF. 2D-PC-MRI is a feasible method for evaluating comprehensively the haemodynamic improvement after revascularisation. Keywords Carotid artery stenting, two-dimensional phase-contrast, total cerebral blood flow volu

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Stroke and cerebrovascular disease, interventional: aneurysms and vascular malformations P.1.081 ENDOVASCULAR TREATMENT OF INTRACRANIAL ANEURYSMS ARISING FROM FENESTRATION:REPORT OF THREE CASES AND THE REVIEW OF LITERATURE S. Milosevic Medenica Department of Neuroradiology, Center of Radiology and MR, Clinical Center of Serbia, Belgrade, Serbia PURPOSE Intracranial arterial fenestrations represent a segmental duplication of intracranial arteries, resulting from abnormal development of primitive embryological vessels. An arterial fenestration may be a site of an aneurysm, as a consequence of hemodynamic stress and wall defect. We describe two cases of ruptured aneurysms within a fenestration of VB junction, successfully obliterated by EVT, and one case of non - ruptured partly thrombosed aneurysm in the ACoA complex treated by EVT and obliterated completely during the second procedure. PRESENTATION OF CASES Case 1. 63-years old patient admitted to Neurosurgery for SAH. Angiography showed an aneurysm arising from one branch of fenestration on VB junction. Another fenestration arm arose from aneurysm dome, as well as right PICA. The aneurysm was excluded by EVT, preserving all branches and the parent vessel. Case 2. 59-years old patient was admitted to Neurosurgery for massive SAH,. Angiography showed an aneurysm inside the fenestration of VB junction with both arms arising from its neck. The aneurysm was obliterated by EVT and all vasculature was preserved. Case 3. 63-years old patient was admitted because of previously proved giant aneurysm in the complex of ACoA.The angiography showed a very complex aneurysm arising from the beginning of fenestrated A2 segment. The patent part sized 12 mm, while the whole aneurysm measured 30 mm. After the first EVT patent part was excluded, but the patient still complained for headaches. After 3 months there was a new aneurysmal growth . This time again all patent part was excluded, but the A2 segment was not filling. Thanks to calateral circulation, patient experienced no symptoms and was dismissed in excellent condition. On the next control the aneurysm was not shown any more, and the A2 was recanalised. CONCLUSION Treating an aneurysm associated with fenestration can be very challenging either from a surgical or endovascular point of view, because of complex relationship of the parent vessel, fenestration arms and parent artery, as well as the perforating branches. The aim of procedure is obliteration of aneurysm with preservation of all branches included. Detailed MSCT angiography and DSA with 3D are mandatory for careful treatment planning. Keywords Intracranial aneurysms, arterial fenestrations, endovascular treatment P.1.082 WHAT ABOUT ANEURYSM SAC THROMBOSIS AT DAY 1 AFTER FLOW-DIVERTER STENTING OF INTRACRANIAL ANEURYSMS? A RETROSPECTIVE CASE SERIES J. Gabrieli, F. Clarençon, F. Di Maria, L. Le Jean, J. Chiras, N. Sourour Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital. Paris VI University, Paris, France PURPOSE The flow redirection in the parent artery provided by the flow diverter stent (FDS) leads to a progressive thrombosis of the aneurysm.

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However, the delay of thrombosis of the aneurysm’s sac remains poorly known. The purpose of our study was to evaluate the early (Day 1) angiographic outcome of aneurysms treated by means of FDS. METHODS Out of 46 patients treated with FDS in our institution between January 2009 and April 2013, 12 patients (26 %); mean age 54y, range 20-75y, 10 females, harbouring 13 unruptured aneurysms, underwent digital subtraction angiography (DSA) at day 1 after FDS(s) deployment. A single device (Pipeline or Silk) was used in 10 cases while 3 were managed with the apposition of either 2 or 3 FDSs; in 3 aneurysms also additional coils were deployed. Post-operative (Day 0) and Day 1 angiographies were retrospectively reviewed and graded by two interventional neuroradiologists in consensus. Day 0 flow modifications were graded as 1-no, 2-minor, 3-major (major flow reduction corresponds to contrast stagnation at venous phase). Angiograms at Day 1 were instead rated on the degree of aneurysmal thrombosis by 1-no, 2-partial, 3-complete thrombosis. Mean aneurysmal size was 14 mm (range 5-28 mm) and mean dome-toneck ratio was 1.8 (range 1.4-3.0). RESULTS Among the 3 patients who had no flow modification at Day 0 none presented intrasaccular thrombosis at Day 1 and only 1 patient had complete occlusion at long term follow-up. Among the 7 patients with major flow modification at Day 0 partial thrombosis was observed in 86 % (6/7) and those (4/7) who had 12months follow-up all showed complete aneurysmal thrombosis. It is noteworthy that the 3 aneurysms treated with additional coiling had at least a partial thrombosis day 1 regardless of flow modifications at day 0 and subsequently progressed to complete thrombosis. CONCLUSIONS Despite the limited number of this case series it seems that among patients treated with FDS, contrast stagnation at venous phase is a good predictor of partial thrombosis at day 1; similarly aneurysms that show partial thrombosis at Day 1 are more likely to progress to complete thrombosis at long term follow-up. Keywords Flow diverter stent, flow modifications, thrombosis

In 88 % of the cases (42/48) a flat-panel volume CT angiography (AXIOM Artis dBC – Siemens, Erlangen, Germany) was performed in the angio suite, just after the stent(s) deployment. The acquisition protocol was as follows: intra-arterial injection in the parent vessel of iohexol 300 mg I/mL diluted at 20 % with saline, coupled with C-arm flat-panel volume CT acquisition with 217° of rotation and 1 image/0.4°. Imaging was reconstructed and analysed on a dedicated workstation (Artis Workplace – Siemens, Erlangen, Germany) with the aid of multiplanar and maximum intensity projections. RESULTS FDS visualization was satisfactory in all the cases, providing partial or total depiction of the device. In 2 cases (5 %) the 3D imaging prompted the operator to perform an additional intra-stent angioplasty for a condition that was previously underestimated. No patient had thrombo-embolic event related to stent kinking/misdeployment. Only one patient experienced thromboembolic complication that was related to Plavix resistance. CONCLUSIONS FPR-CTA is an interesting tool to depict FDS misdeployment and may encourage the operator to perform intra-stent angioplasty (5 % of the cases in our experience) to avoid delayed thrombo-embolic complication. Disclosure Dr Sourour is proctor for pipeline device. Keywords Flow diverter stent, volume CT angiography, flat-panel

P.1.083 INTEREST OF FLAT PANEL VOLUME CT ANGIOGRAPHY TO EVALUATE THE ACCURATE DEPLOYMENT OF FLOWDIVERTER STENTS

OBJECTIVE To compare the clearness of radiodiagnostics methods for planning the open surgical treatment of arterial aneurysms under the navigational control. METHODS The researches were carried out with the help of the 160-section CAT scanner “Aquilion PRIME” by Toshiba and the MRI system “Signa Excite” 1,5 T. The data obtained by CT-angiography and MR-imaging in the SPGR sequence was imported into the navigational station of Medtronic company, and synchronized with the operational microscope. 8 patients were operated on with distal aneurysms M2 and M3 segments of the medial cerebral artery, A3 segment of the anterior cerebral artery. For intracranial vessels visualization CT-angiography was performed on 4 patients, and MR-imaging in the regime on 4 patients. There was used a synchronization of the navigational station with the microscope Pentero. RESULTS The patient’s head registration in the navigational station was performed by native axial sections of MRI in the SPGR sequence and axial scans of CT-angiography, without resorting to fusion with other research methods. All the methods allowed to visualize the saccular arterial aneurysm. The best arterial aneurysm visualization with its neck detailing was obtained during CT-angiography. The use of the given diagnostics methods allowed to fulfill the surgical interventions successfully on all the patients with saccular arterial aneurysms under the navigational station control by the

J. Gabrieli, F. Clarençon, F. Di Maria, L. Le Jean, J. Chiras, N. Sourour Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital. Paris VI University, Paris, France PURPOSE Flow Diverter stents (FDS) have gained acceptance during the past 4 years for the treatment of some intracranial aneurysms, especially the giant/large ones. However, one of the major drawbacks for the use of this device is its poor radiopacity that may lead to missing of kinking or misdeployment of the stent, with potential severe clinical consequences. The purpose of this study was to investigate the interest and clinical impact of stent-dedicated flat-panel volume CT-angiography (FPVCTA) to evaluate the satisfactory deployment of the FDS. METHODS From January 2009 to April 2013, 47 consecutive patients (mean age 50y, age range 20-77y, 34 females) were treated, under general anaesthesia, with FDS (30 Pipeline, 10 Silk, 6 NeuroEndograft, 2 FRED. 47 aneurysms (41 unruptured, 6 ruptured; 41 anterior, 6 posterior circulation) were treated in 46 patients (one patient had 2 aneurysms both treated by means of FDS). One patient was treated for a traumatic carotid-cavernous fistula.

P.1.084 INTRACRANIAL VESSELS VISUALIZATION FOR KEY-HOLE S UR GE RY OF ART E RI AL A NE URY SM S U ND ER THE NAVIGATIONAL CONTROL A. Arablinsky, A. Gorozhanin, I. Danchenko, D. Vakatov, A. Osipovskay Moscow State Medical Institution Municipal Clinical Hospital N.A. S.P. Botkin, Moscow, Russia

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minimally invasive access complying with the key-hole surgery principles. CONCLUSIONS The clearest method for intracranial aneurysms visualization which can be successfully imported into the navigational station and used for surgical treatment is the CT-angiography. MRI in the SPGR sequence is the alternative method used for navigational planning of surgical treatment on patients with the allergic reaction to iodine-containing contrast medicine. Keywords Radiodiagnostics methods, CT-angiography and MR-imaging, surgical treatment of arterial

P.1.086 ROLE OF COMPUTED TOMOGRAPHY ANGIOGRAPHY/ PERFUSION (CTA-CTP) IN THE BLOOD PRESSURE (BP) MANAGEMENT IN ACUTE SUBARACHNOID HEMORRAGE (SH) DUE TO ANEURYSM RUPTURE

P.1.085 ENDOVASCULAR TREATMENT OF ACUTELY RUPTURED WIDE-NECKED INTRACRANIAL ANEURYSMS: SAFETY AND EFFICACY OF DOUBLE MICROCATHETER TECHNIQUE

PURPOSE Brain aneurysm rupture is an internal neurological trauma that represent a common cause of death and disability worldwide. The current literature supports an association between PCT/CTA, BP and patient outcome during SH. Aim of this paper is to analyse the correlation between PCT/CTA finding and outcome to support BP management during SH. METHODS 236 consecutive patients with symptomatic SH (mean age 58,7y, April 2009-March 2013), Fisher 2 (76.27 % [180/236]), 3 (18.22 % [43/236]), 4 (5.5 % [13/236]) and CTA evidence of intracranial aneurysm undergoing endovascular coiling, with subsequent permanent exclusion. The PCT penumbra areas correlates with hypoperfusion. Patients’ age, sex, Hunt-Hess score at presentation and vasospasm evaluated with TICI (Thrombolysis in Cerebral Ischemia: grade 0 (no flow) grade 3 (normal flow)) were recorded and correlated using a multiple logistic regression analysis. RESULTS PCT and CTA were independent predictors of good clinical outcome. Hypotension and hypertension are correlated with poor outcome, but the effect of reducing or augmenting excessively BP is unclear. In 83.47 % patients (197/236) BP was treated only when systemic BP is greater than 220 or greater than 180 in candidates for embolization. In 87.71 % (207/236) the systolic BP greater than 140 has been correlated with poor outcomes (mRS 3–5) p<0.005. The use of vasopressor drugs to treat hypotension was limited to concomitant vascular malformation presence. CONCLUSIONS Although recent studies report the safety and feasibility of early BP reduction in hemorrhagic stroke, PCT/CTA can help to prevent complications, the optimal hemodynamic parameters are not clearly defined in this patient population. Keywords Aneurysm, subarachnoid hemorrage, stroke

P. Yoon1, J. Lee1, Y. Lee2, K. Yang2 1

NHIS Ilsan Hospital, Department of Radiology, Goyang, South Korea, 2NHIS Ilsan Hospital, Department of Neurosurgery, Goyang, South Korea PURPOSE Use of the stents for treatment of wide-necked intracranial aneurysms is controversial in the setting of acute subarachnoid hemorrhage because of concerns about the risk of using antiplatelet therapy. Double microcatehter technique is an alternative for treatment of wide-necked intracranial aneurysms and it does not require antiplatelet therapy. In this study we evaluate the safety and efficacy of this technique for the treatment of acutely ruptured wide-necked aneurysms. METHODS A retrospective review of 41 patients with ruptured wide-necked intracranial aneurysms treated with double microcatheter technique was done. The angiographic results, treatment-related complications, and clinical outcome were documented. Glasgow Outcome Scale (GOS) was used for clinical outcome. Angiographic follow-up using digital subtraction angiography or magnetic resonance angiography was available in 22 patients and length of angiographic follow-up ranged from 3 to 40 months with mean of 15.2 months. Both postembolization and follow-up angiograms were graded on a 3-point Raymond scale. Aneurysms were classified as stable, improved, or recanalized based on the follow-up angiograms. RESULTS On the postembolization angiograms, 18 (43.9 %) aneurysms showed complete occlusion (Raymond 1), 13 (31.7 %) showed neck remnant (Raymond 2), and 10 (24.4 %) showed body remnant (Raymond 3). Treatment-related complications occurred in 4 patients (9.8 %) and the treatment-related morbidity rate was 2.4 % (1/41). A good outcome (GOS 4 or 5) was observed in 58.5 % of patients at the time of discharge and 5 patients died. The overall mortality rate was 12.2 % (5/41), however, the treatment-related mortality rate was 0 %. Of the 22 aneurysms in which angiographic followup was available, 9 (40.9 %) aneurysms showed stable and 13 (59.1 %) aneurysms demonstrated recanalization. Four (30.8 %) aneurysms with recanalization were retreated endovascularly; there was one aneurysm of re-rupture in follow-up, which was incompletely packed initially. CONCLUSIONS Double microcatheter technique is safe and effective for coil embolization of acutely ruptured wide-necked intracranial aneurysms with a low treatment-related complication, morbidity, and mortality rate. However, the high rate of postembolization incomplete occlusion and recanalization remains the main challenge. More and longer term angiographic follow-up information is needed to better define the durability of treatment. Keywords Aneurysm, double-microcatheter technique, endovascular treatment

E. Puglielli1, M. Bafile2, M. Fuschi1, M. Varrassi1, V. Di Egidio3 1

Interventional and Vascular Radiology, G. Mazzini Hospital, Teramo, Italy, 2Department of Anesthesia and Intensive Care, S. Salvatore Hospital, L'Aquila, Italy, 3General and Interventional Radiology, S. Spirito Hospital, Pescara, Italy

P.1.087 CLINICAL AGGRESSIVE CAVERNOUS SINUS DURAL ARTERIOVENOUS FISTULA: ANGIO-ARCHITECTURE ANALYSIS AND EMBOLISATION BY VARIOUS APPROACHES C. Luo1, Y. Tsai3, F. Chang1,2, M. Teng1,2, C. Lin1,2, W. Guo1,2 1 Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, 2Department of Radiology, National Yang-Ming University School of Medicine, Taipei, Taiwan, 3Department of Diagnostic Radiology, Chang-Gung Memorial Hospital, Chiayi, Taiwan

PURPOSE Most cavernous sinus dural arteriovenous fistulas (CSDAVFs) are commonly presented with neuro-ophthalmic symptoms. CSDAVFs manifest with clinical aggressive symptoms such as hemorrhagic or non-hemorrhagic neurologic deficits is rare. The purpose of this study is to analysis the angio-architectures of clinical aggressive CSDAVF and to report our experiences of endovascular management.

S110 METHODS In the past 10 years, a total of 107 CSDAVF had been managed by embolization. From these databases, five patients were found to have clinical aggressive CSDAVF. There were 4 women and 1 man, age ranged from 58 to 78 years (mean: 68). We retrospectively analyzed the angioarchitecture of clinical aggressive CSDAVF and endovascular outcomes by various accesses to the cavernous sinus. RESULTS The causes of clinical aggressive of CSDAVF were poor venous drainage of CSDAVFs because of occlusion of inferior petrous sinus (IPS) with reflux to veins of brainstem (n=4) leading to non-hemorrhagic brainstem edema/ ischemic change (paresis in 3, paresis and respiratory failure in 1), while one fistula flow reflux to superficial middle cerebral vein demonstrating intracranial hemorrhage and presented with paresis. Transvenous access via occluded IPS to fistula was attempted in all 5 patients, but failed in 4; three underwent trans-orbital access, while trans-arterial embolization by using liquid adhesive was performed in 1. Total fistula occlusion was achieved in all 5 patients. All patients had totally resolution of their symptoms within three months. No permanent peri-procedural neurologic complication was found. Mean clinical follow-up period was 16 months. CONCLUSIONS Aggressive CSDAVFs always associated with occlusion of IPS with leptomeningeal reflux and may associate with clinical aggressive symptoms such as hemorrhagic or non-hemorrhagic neurologic events. Embolization is a feasible and safe method to manage these clinical aggressive CSDAVFs. However, transvenous access via occluded IPS may fail. Trans-orbital access or trans-arterial embolization is alternative with promising results in this limit case analysis. Keywords Cavernous sinus, dural arteriovenous fistula, embolisation P.1.088 DOUBLE MICROCATHETER TECHNIQUE FOR COIL EMBOLIZATION OF OVERWIDE AND UNDERTALL SMALL ANEURYSMS D. Kim, B.M. Kim, N.Y. Shin, E.H. Ihm, J.H. Baek, D.I. Kim Yonsei University College of Medicine, Department of Radiology, Seoul, South Korea PURPOSE To evaluate the preliminary feasibility and results of double microcatheter endovascular coil embolization of overwide and undertall small intracranial aneurysms. METHODS From July 2010 to Jan 2013, small (<7 mm), overwide (dome to neck ratio (DNR)=<1.2), and undertall (ASPECTS ratio=<1.2) aneurysms which were treated with double microcatheter technique were selected. For the double microcatheter technique, 2 microcatheters were selected simultaneously into the aneurysm sac and coil insertion was performed alternatingly. The initial results, complications, and follow up results were assessed. RESULTS Thirteen patients (mean age: 52.5 years, range 33–73 years) with small (mean size 3.9 mm, range; 2.5-5.5 mm), overwide (mean DNR;1.1, range;0.9-1.2), and undertall (mean ASPECTS ratio; 1.0, range; 0.7-1.2) aneurysms were treated with the double microcatheter technique. The indication for treatment were rupture (n=1), rupture of another aneurysm (n=2), or aneurysm with lobulations / daughter sac (n=10). The location of the aneurysms were Acom (n=6), MCA bifurcation (n=3), ophthalmic (n=2), AchA (n=1), and IC-Pcom (n=1). Complete or near complete occlusion was achieved in 12/13 aneurysms. Adjuvant balloon remodeling was performed in 3 patients due to microcatheter instability (n=2) and poor working projection (n=1). Coiling failed in one patient with both

Neuroradiology (2013) 55 (Suppl 1):S15–S159 ASPECTS and DNR <1.0. One patient developed transient in-situ thrombus which was resolved IA tirofiban. No patients developed newly developed symptoms on clinical follow up (mean; 7.1mo, range; 1–29.6mo). CONCLUSION Double microcatheter technique may be a safe and effective method for treatment of overwide and undertall small intracranial aneurysms. Keywords Aneurysm, coil, embolization

Stroke and cerebrovascular disease, interventional: vessel obstructions and recanalisation P.1.089 SAFETY AND OUTCOME OF ACUTE STROKE TREATMENT WITH THE SOLITAIRE FR STENT RETRIEVER IN 227 PATIENTS P.P. Gratz1, S. Jung2, G. Schroth1, J. Gralla1, P. Mordasini1, K. Hsieh1, M.R. Heldner2, H.P. Mattle2, M. Mono2, U. Fischer2, M. Arnold2, C. Zubler1 1

Department of Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland, 2Department of Neurology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland PURPOSE Stent retrievers have become an important adjunct in the treatment of patients with ischemic stroke. Previous studies reported high rates of successful reperfusion and favorable outcome after treatment with this technique. The aim of this study was to analyze outcome and complications in a large cohort of patients with anterior circulation stroke treated with the Solitaire stent retriever with additional focus on patients treated outside standard treatment protocols: equal to or older than 80 years of age, ischemic signs in more than one third of the middle cerebral artery (MCA) territory, and time from symptom onset to endovascular intervention more than 8 hours. METHODS Consecutive patients presenting with acute ischemic stroke in the anterior circulation treated with the Solitaire were analyzed. Data on characteristics of endovascular interventions, complications and clinical outcome were collected prospectively in our stroke database. Patients treated outside were compared with those treated within standard protocols. RESULTS 227 patients (mean± standard deviation, 68.2 ± 14.7 years) were included. Median National Institutes of Health Stroke Scale (NIHSS) score on admission was 16 (range, 2–36). Successful reperfusion (Thrombolysis in Cerebral Infarction [TICI] grades 2b-3) was achieved in 70.9 %. Favorable outcome (modified Rankin scale [mRS] 0–2) was seen in 64.4 % of patients treated within and 19.6 % treated outside standard protocols. The rates for symptomatic intracranial hemorrhage (sICH) were 3.8 % and 15.1 %, for death 11.0 % and 42.0 %, and for symptomatic intra-procedural complications 3.8 % and 4.2 %, respectively. CONCLUSIONS Patients less than 80 years of age without extensive pre-treatment ischemic signs had high rates of favorable outcome and low periprocedural complication rates after treatment with the Solitaire. Less favorable outcomes, despite similarly low intra-procedural complication rates, in patients not fulfilling these criteria indicate that further research should focus on optimal patient selection for endovascular stroke treatment. Keywords Thrombectomy, solitaire, acute ischemic stroke

Neuroradiology (2013) 55 (Suppl 1):S15–S159 P.1.090 CHANGES OF CEREBRAL PERFUSION IN PATIENTS WITH MODERATE AND SEVERE CAROTID ARTERY STENOSIS AFTER STENTING A. Sergeeva, M.V. Krotenkova, R.N. Konovalov, A.S. Suslin, M.A. Piradov Research Center of Neurology RAMS, Moscow, Russia PURPOSE To assess changes in cerebral perfusion, measured with computed tomography perfusion (CTP) imaging, in patients with moderate and severe ICA stenosis after unilateral transluminal angioplasty and stent placement. METHODS Ten patients with moderate ICA stenosis of 50-69 % (median age 67 years) and 12 patients with severe ICA stenosis (median age 62 years) underwent CTP before stenting and 3–7 days and 1–3 months after the procedure. Control group included 15 otherwise healthy subjects with mild hypertension (median age 60 years), who underwent CTP. Mean transit time (MTT), cerebral blood volume (CBV), and cerebral blood flow (CBF) were calculated in the middle cerebral artery (MCA) area, watershed between anterior cerebral artery and MCA territories (anterior watershed), and watershed between posterior cerebral artery and MCA territories (posterior watershed). Since some patients had contralateral mild to moderate ICA stenosis, absolute values of perfusion parameters were evaluated on the side of the intervention. RESULTS Patients with moderate ICA stenosis before endovascular therapy demonstrated increased MTT and decreased CBF in MCA territory (p=0.005 and p=0.003, respectively) and posterior watershed (p=0.02 for MTT, p=0.03 for CBF) compared to control group. These parameters improved in 3–7 days after the intervention, so that there was no significant difference versus control group, and this effect remained up to 1–3months. In the group of patients with severe ICA stenosis before stenting an increase of MTT and a decrease of CBF were observed in all vascular territories (p<0.001 for all parameters) versus control group. Three to seven days after the intervention all perfusion parameters improved and showed no difference compared to the control group, but in 1–3 months after stenting perfusion alternations were noted in both watershed territories (p<0.05 for both increased MTT and decreased CBF in both zones). In MCA territory all parameters remained the same. CONCLUSIONS Endovascular stent placement steadily improved cerebral hemodynamics in patients with moderate symptomatic ICA stenosis. Revascularization led to perfusion benefit in patients with severe ICA stenosis immediately after the procedure, but 1–3 months later perfusion deficit in watershed territories was demonstrated. Keywords CT perfusion, carotid artery stenosis, endovascular stent placement P.1.091 RADIOLOGIC EVALUATION OF TOP OF THE BASILAR SYNDROME Y. Kiroglu1, C. Oncel2, A. Kocyigit3 1

Pamukkale Univ. Medical Faculty, Department of Radiology, Denizli, Turkey, 2Pamukkale Univ. Medical Faculty, Department of Neurology, Denizli, Turkey, 3Pamukkale Univ. Medical Faculty, Department of Radiology, Denizli, Turkey PURPOSE To characterize the complete imaging spectrum of top of the basilar syndrome (TOBS). METHOD Imaging and clinical datas of 25 patients with TOBS infarction from 2006 to 2013 were reviewed retrospectively. The primary imaging

S111 criterion for inclusion was an abnormal signal intensity on MR imaging and detecting an stenosis/oclusion in defined TOB arteria territories. RESULTS The most common affected vessel site of TOB arterial territory was unilateral P1segment in 9 patients, bilateral P1 segment in 7, distal or tip of the BA in 14 and SCA in 6 patients. Stenosis or occlusion was unilateral in 12 (%48) and bilateral in 13 (%52) patients. The most common infarcted localization was thalamus, affected in 18 patients (unilateral in 8, bilateral in 9 patients) and followed by unilateral medial occipital lobes in 8, bilateral medial occipital lobes in 4, unilateral medial temporal lobes in 4, bilateral medial temporal lobes in 3, unilateral superior cerebellum in 7, bilateral superior cerebellum in 1 patiens and 8 pons sites. Arterial dissection was diagnosed in four patients located in left proximal VA in and distal BA. The most frequent initial symptoms were loss of consciousness, muscle weakness, visual and behavioral disturbances. The major risk factors were diabetes mellitus (DM), hypertension (HT), rheumatismal cardiac diseas (RCD), chronic renal disease (CRD) and esansieal thrombositosis. CONCLUSION The accurate evaluation with imaging findings of TOB-S is essential for the diagnosis and appropriate management. Familarity with the territorial ischemic lesions and infarction patterns seen in the TOB-S with MR and DWI can help radiologists to recognize these lesions and correlate the patient’s clinical presentation with the radiological findings. The dedection of the acute ischemic lesions in characteristic distrubition or the distal BA territory on DWI is unique for the early TOB-S diagnosis. The most sensitive examination to demonstrate vascular disturbance is DSA but MR and DWI are the investigation of choises. Keywords Basilar artery, stroke, ischemia P.1.092 ISCHEMIC BRAIN CHANGES ASSOCIATED WITH CEREBRAL ANGIOGRAPHY EVALUATION OF DIFFUSION WEIGHTED MAGNETIC RESONANCE IMAGING T. Ikizceli 1 , H. Donmez 2 , E. Serifov 3 , A. Candan Durak 2 , G. Kahriman2, S. Senol2 1 Haseki Education and Researc Hospital, Istanbul, Turkey, 2University of Erciyes, School of Medicine, Kayseri, Turkey, 3The Centre of Nahcivan Hospital, Baku, Azerbaijan

BACKGROUND AND PURPOSE The aim of this study is to evaluate the incidence of clinically silent embolic cerebral infarctions and associated risk factors following diagnostic cerebral angiography with diffusion-weighted magnetic resonance imaging (DWI). METHODS A total of 71 cerebral digital substraction angiograms (42 male, 29 female, average age: 56.0±15.0) obtained using nonionic contrast material were prospectively evaluated. To asses embolic events, before and after (1–3 days) angiography, DWI was performed. The risk factors for embolic ischemic brain changes such as patient age and sex, atherosclerotic vessel wall disease, type of indication for catheter angiography, the number and size of used catheters, difficult anatomy, selective/nonselective catheterization, contrast media volume, and time of procedure were determinated. Fisher exact tests and a Student-t test were used for the statistical analyses of outcomes. RESULT Thirteen new silent ischemic lesions were identified in 7 of 71 patients who underwent diagnostic cerebral angiography. Embolic cerebral lesions were often 6–10 mm in diameter. According to the findings in this study there was a strong correlation between diffusion abnormality and patient age which was considered as risk factors (p<0.05). However, there was no significant corelations between other risk factors and lesions appearance (p>0.05).

S112 CONCLUSION In elderly patients, the angiographic procedures should be performed meticulously and should be obtained routine DWI in all patients even if normal neurological examination normal. In this way presence of microemboli and clinical results can be evaluated. Keywords Cerebral angiography, diffusion magnetic resonance i, embolism P.1.093 DETECTION OF EMBOLIC COMPLICATIONS FOLLOWING STENT RETRIEVER DEPLOYMENT IN ANTERIOR CIRCULATION STROKES: AN SWI STUDY P.P. Gratz1, G. Schroth1, C. Weisstanner1, U. Fischer2, S. Jung2, M.R. Heldner2, C. Kiefer1, J. Gralla1, P. Mordasini1, F. Kellner-Weldon1, C. Zubler1, K. Hsieh1, M. El-Koussy1 1 Department of Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland, 2Department of Neurology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland

PURPOSE Stent retrievers are recently introduced endovascular thrombectomy devices. While being highly effective in the treatment of ischemic stroke, their use carries the potential risk of embolic complications. Susceptibility-weighted imaging (SWI) is an MRI technique sensitive for the detection of thromboembolism. This study examines the occurrence of peri-interventional embolic events as depicted by SWI. In addition, the ability of SWI in determining thrombus location before endovascular intervention is compared with other imaging modalities METHODS 292 patients with acute anterior circulation stroke treated with stent retrievers were retrospectively analyzed. Patients with pre- and post-interventional SWI were included and screened for peri-interventional embolism. Thrombus location depicted by SWI before intervention was compared to that seen on time-of-flight (TOF) magnetic resonance angiography (MRA), first-pass gadolinium enhanced MRA, and digital subtraction angiography (DSA). RESULTS 42 patients fulfilled the inclusion criteria. In 9 patients (21.4 %) 10 minute, punctate emboli were detected in the treated middle cerebral artery (MCA) territories on SWI (one patient had 2 emboli). There was no association between the occurrence of embolic events and clinical outcome, reperfusion success, thrombus length, technique of the endovascular intervention, or post-procedural intracranial hemorrhage. The length of the thrombus on pre-interventional SWI was 12.0±5.1 mm (mean±standard deviation). There was a strong correlation between thrombus location on SWI with that seen on TOF, first-pass gadolinium enhanced MRA, and DSA. CONCLUSIONS SWI aids in the detection of peri-interventional embolic events. The low burden of peri-interventional emboli was not associated with a negative impact on clinical outcome. Keywords SWI, stent retriever, acute ischemic stroke

Other/free topics P.1.094 PEDIATRIC SJÖGREN-LARSSON SYNDROME AND ADULT PRIMER SJÖGREN’S SYNDROME: BRAIN INVOLVEMENT H. Kalkan, O. Babaoglu, D. Kiresi Necmettin Erbakan University, Meram School of Medicine, Department of Radiology, Konya, Turkey

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Sjögren Larsson syndrome (SLS), is a neurocutaneous disorder that is inherited autosomal recessive. Peak incidence is approximately 0.4 per 100.000. Classic triad is congenital ichthyosis, spastic diplegia or tetraplegia and mental retardation. Medium and long-chain fatty aldehydes can’t be oxidated because of the deficiency of aldehyde dehydrogenase enzyme. Brain magnetic resonans imaging(MRI) is performed for neurological symptoms and there is T2WI hyperintensity in periventriculer white matter and corticospinal tract. On Proton MR Spectroscopic(MRS) analysis, there is lipid peak at 1.3 ppm and high myoinositol levels. These are due to lipid acumulation and delayed myelinisation. Primer Sjögren’s syndrome(PSS) is an autoimmun disease that affect %2-3 of adults. Central nevre system involvement is rare.. Patients suffer from dry eye and mouth. Brain MRI shows increased signal intensity on T2WI at periventriculer white matter. PURPOSE We aimed to discuss the brain involvement of pediatric SLS and PSS with the MRI and MRS findings. METHODS AND RESULTS Case 1: 2 year old boy , applied for motor-mental retardation, ichtiyosis. He was performed brain MRI and MRS. There was periventriculer white matter hyperintensities on T2WI . Spectra of the periventriculer white matter showed a narrow lipid peak at 1.3 ppm. Also, at 3.8 ppm, there was reverse myoinositol peak . Case 2: 54 year old woman applied for dry mouth, leg paresthaesia. Autoantibodies, such as antinuclear, anti-Ro, anti-La, and rheumatoid factor and schirmer test were positive. Salivary gland biopsy confirmed the diagnose of primer Sjögren’s syndrome. On T2WI and FLAIR, there was increased intensity at periventrivuler white matter and corticospinal tract. MRS of white matter had normal spectroscopic findings. DISCUSSION As SLS is a rare inherited disease of pediatric age group; PSS is an autoimmune disorder of adults. These two disease have different symptoms and occure at different age groups. They are similar with the involvement of periventriculer white matter. SLS is diagnosed by typical MRS findings. PSS has no abnormal MRS peak of metabolites in comparison with SLS. PSS is diagnosed by clinical findings, laboratory values and biopsy of the salivary gland. Keywords Magnetic resonans spectroscopy, Sjögren Larsson syndrome, primer Sjögren syndrome P.1.095 NORMAL BASAL GANGLIA SIGNAL FROM 3 T AND 1.5 T MRI SCANNERS IN DIFFERENT AGE GROUPS N. Leela, A. Rana Aberdeen Royal Infirmary, Aberdeen, United Kingdom BACKGROUND The signal intensity from the basal ganglia reduces with increasing age however there are no published studies on this and on the difference between 1.5 T and 3 T. OBJECTIVE To demonstrate the change in signal intensity with age and to 1.5 and 3 T field strengths. METHODS T1 and T2 weighted images of randomly selected patients from a Philips 3 T MRI scanner and a Siemens 1.5 T scanner were retrospectively reviewed. The patients were divided into age groups of 1–10, 10– 20, 20–40, 40–60, 60–80 and 80+ years. Up to 15 patients were reviewed in each age group. Basal ganglia signal was compared with the cortical grey matter as the internal control for each image.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 RESULTS A total of 129 subjects of ages ranging from 1 week to 89 years were reviewed. The basal nuclei become hypointense relative to the cortical grey matter with increasing patient age. At 3 T the basal nuclei become hypointense in the 20–40 age group, and at 1.5 T the basal nuclei become hypointense in the 40–60 age group. CONCLUSIONS The reduction of basal nuclei signal intensity with age has been confirmed. The basal nuclei become hypointense relative to cortical grey matter at an earlier age on 3 T MRI compared to 1.5 T. Keywords Normal basal ganglia, MRI, change with age P.1.096 HYPOPHYSIS MRI FINDINGS DUE TO IRON OVERLOAD IN TWO TRANSFUSION- DEPENDENT BETA THALASSAEMIA MAJOR PATIENTS H. Kalkan, D. Kiresi Necmettin Erbakan University, Meram School of Medicine,Department of Radiology, Konya, Turkey Beta thalassemia major is a hereditary anemia. Patients are treated with repeated blood transfusions to prevent from anemia. Because of this, iron accumulates at different parts of the body; spleen, liver then in myokard and endocrine glands.Hypogonadotropic hypogonadism and growth hormon deficiency is the result of iron deposition at the pituitary gland. PURPOSE We aimed to describe the pituitary magnetic resonans imaging (MRI) findings of two thalassemia patients who presented with hypogonadotropic hypogonadism. MATERIALS AND METHODS Case 1 15 year old female diagnosed as beta thalassaemia major in her 6 monthsyear old suffered from delayed puberte, short stature. Ferritin level was high and there was a heterozygous mutation of MTHFR. She was treated with desferroksamine. There was iron deposition in liver. Hypophysis MRI reveled that height of pituitary gland decreased, enhancement of the gland significantly reduced and gland was hypointense on T2WI. Case 2 20 year old female with thalassemia major presented with short stature and amenorrhea in her 13 year old. She had iron acumulation in spleen, liver and myocard. Her ferritin was high, FSH and LH ,GH levels were low. She had HFE gene mutation. She was performed pituitary MRI for the symptoms. Gland was short in central, on T2WI the intensity was lower than expected and enhancement was lower than normal after contrast injection. DISCUSSION Beta thalaseamia major is treated with transfusion. This leads iron deposition in different parts of the body especially liver, spleen, myocard and pituitary. Those two tranfusion dependent patients in this article, had the symptoms and laboratory values of hypogonadothropic hypogonadism due to iron overload in pituitary gland. MRI findings confirmed the deposition .Signal intensity of the gland was slightly reduced on both T1- T2WI. Pituitary gland height decreased. Thyroid, adrenals and gonads are also affected in patients with thalaseamia; however our patients were spared. Cardiac failure is the leading cause of death from iron overload in patients with thalassaemia. Only the second patient had myocardial involvement. As a result, if thalaseamia major patients presented with the symptoms of hypogonadotropic hypogonadism they must be performed MRI to see the iron acumulation in pituitary gland. Keywords Thalassemia major, pituitary gland, iron overload

S113 P.1.097 ASSESSMENT OF NEURAL IMPAIRMENT IN OBSTRUCTIVE SLEEP APNOEA SYNDROME: CAN APPARENT DIFFUSION COEFFICIENT MEASUREMENTS BE USEFUL? E. Kacar1, S.S. Ulasli2, G. Gungor1, E. Unlu1, T. Koyuncu2, A. Haktanir1, M. Unlu2 1

Kocatepe University, Department of Radiology, Afyonkarahisar, Turkey, 2Kocatepe University, Department of Respiratory Diseases, Afyonkarahisar, Turkey PURPOSE To investigate whether neurological impairment in patients with obstructive sleep apnoea syndrome (OSAS) with apparently normal cerebral and cerebellar structures can be assessed by means of apparent diffusion coefficient (ADC) measurement, and to evaluate the relationship between OSAS severity and ADC values. METHODS Following the acquisition of diffusion-weighted imaging (DWI), ADC measurements were performed in 24 different apparently normal cerebral and cerebellar structures, including the bilateral frontal and parietal cortex, insula, cingulate gyrus, hippocampus, frontal and parieto-occipital periventricular white matter (PWM), caudate nucleus, putamen, thalamus, cerebellar hemisphere, pons, and midbrain in 47 OSAS patients and 20 control subjects. The ADC values of the patients and the control group were statistically compared. The relationship between the apnoea–hypopnea index (AHI) and the ADC values of the patients was investigated. RESULTS The ADC values in the bilateral frontal periventricular white matter were lower in the patient groups than in the control subjects (P<0.05). The measurements in the right cingulate gyrus of the OSAS patients exhibited significantly higher ADC values than those of the control group (P=0.002). Bilateral thalamic ADC values in severe OSAS patients were significantly higher than those in mild and moderate OSAS patients (P<0.05). CONCLUSIONS The ADC measurement is a simple and effective technique to evaluate neural impairment of the brain in patients with OSAS. ADC measurements can also be useful in the evaluation of the relationship between the AHI and the degree of neural impairment in the central nervous system, and may provide different strategies for treatment. Keywords Obstructive sleep apnea, brain, diffusion weighted MRI P.1.098 ACUTE INFARCTIONS IN PATIENTS WITH COGNITIVE FUNCTION IMPAIRMENTS Y. Hwang, S. Lee, B. Lee, S. Kim Inje University Ilsan Paik Hospital, Goyang, South Korea PURPOSE This study aims to evaluate the incidental rate and characteristics of acute infarcts on brain MRI in patients with subjective cognitive function impairments. METHODS We retrospectively analyzed acute infarcts on brain magnetic resonance images in 348 patients with subjective cognitive function impairments. The MR protocols included conventional T2-weighted axial images, fluid-attenuated inversion recovery axial images, T1-weighted coronal 3D magnetizationprepared rapid acquisition of gradient echo, and diffusion tensor images. We evaluated the acute infarctions on a trace map of the diffusion tensor images. RESULTS Twelve patients showed increased signal intensity on the trace map of the diffusion tensor images, suggesting acute infarction. The incidental rate of

S114 acute infarctions in patients with cognitive function impairments was 3.45 %. Eight patients had a single lesion, and four patients had multiple lesions. CONCLUSIONS An acute infarction as an incidental finding was detected in patients with subjective cognitive function impairments, and the incidence of acute infarctions was higher than in the general population. It will be helpful in the early detection and treatment of ischemic lesions to evaluate carefully the MR images of patients with cognitive function impairments. Keywords Dementia, MRI, cerebral infarction P.1.099 RADIOGRAPHIC SCREENING OF SCOLIOSIS: PREVALENCE STUDY IN YOUNG KOREAN MILITARY RECRUITS T. Ha, K. Chang, J. Hur Incheon Regional Military Manpower Administration, Incheon, South Korea PURPOSE To assess the prevalence of scoliosis among young male recruited by the Military Manpower Administration in Korea. METHODS A retrospective cross-sectional study was performed by analyzing chest radiograph taken from all young male recruits in Incheon Regional Military Manpower Administration from April,1 2011 to Mar 31,2013. A thoracolumbar standing anterior-posterior radiograph was taken when suspected scoliosis in chest radiograph. More than 10 degree Cobb angle in thoracolumbar standing anterior-posterior radiograph was diagnosed as scoliosis. RESULTS Total 80509 chest radiographs were taken. Among of them, 1671 thoracolumbar standing anterior-posterior radiographs were taken for confirming scoliosis. Diagnosed as scoliosis was 795. It was categorized according to cobb angle that consist of 652(10~25 degree), 122(25~40 degree) and 21 (> 40 degree). Each of them was 82.0 %, 15.3 %,2.7 % in total scoliosis.Mean cobb angle is 20.5 degree±8.0. CONCLUSION In young Korean male military recruits, the overall prevalence of scoliosis was 0.98 %, which was relatively lower than another recent studies. Keywords Radiograph, scoliosis, prevalence P.1.100 EMERGING ROLE OF ULTRASOUND IMAGING ASSOCIATED TO CLINICAL NEUROPHYSIOLOGY AS A SUPPLEMENTARY DIAGNOSTICS TECHNIQUE OF PERIPHERAL NERVES PATHOLOGIES: A SICILIAN EXPERIENCE A. Gagliardo1, 2, C. Avarino1, G. Giaimi1, D. Di Matteo1, M. Midiri2, C. Gagliardo 2 1

Clinical Course, Neurophysiology Unit, NHS accredited, Palermo, Italy, DI.BI.MEF, Radiology Section, University of Palermo, Palermo, Italy

2

PURPOSE To show the relevance of peripheral nerve ultrasound imaging as a supplementary technique in a clinical neurophysiological evaluation. METHODS Peripheral nerves ultrasound (US) examination was performed in patients with a medical history of nerve entrapment and/or posttraumatic neuropathy but with clinical or neurophysiological unusual findings. A 10–18 MHz transducer was used. RESULTS We recruited 50 patients with clinical evidence of peripheral neuropathies (25 M, 25 F): 24 median nerves, 1 anterior interosseous, 14 ulnar, 3 brachial plexus, 2 posterior interosseus, 1 superficial radial, 1 superficial

Neuroradiology (2013) 55 (Suppl 1):S15–S159 peroneal and 4 common peroneal nerves. Overall 20/50 patients had a history of trauma: 4/24 patients with median pathology, 6/14 ulnar, 3/4 common peroneal, 1/2 posterior interosseous and all cases of involvement of the brachial plexus, superficial peroneal and superficial radial nerves. CONCLUSIONS Our data show that peripheral nerve US is advisable: in all patients with post-traumatic etiology (40 %) as it could reveal neuromas and neurotmesis; in all post-surgical iatrogenic onset neuropathies for the uncommon sites of injury; in severe diseases with not evocable nerve at the neurophysiological examination; in patients with diffuse pre-existing (and confounding) neurophysiological alterations (but with clinical suspect of new neuropathy); in entrapment neuropathies for screening purpose (we found concomitant tenosynovitis in 21.7 % of carpal tunnel syndromes; dynamic ulnar nerve luxation at the elbow in 28.5 % of case); in all brachial plexus pathologies as multiple sites of injury – i.e. radial, ulnar and posterior interosseous have been documented; for early selection of surgical candidates and post-surgical patients monitoring. Keywords Peripheral nerves, ultrasound imaging, clinical neurophysiological P.1.101 DO EXPERT SECONDARY READS OF OUTSIDE NEUROIMAGING EXAMINATIONS ADD CLINICAL VALUE? G. Fletcher1, J. Melikian2, M. Patel1 1

Mayo Clinic Arizona, Dept of Diagnostic Radiology, Scottsdale, AZ, USA, 2Arizona State University, Tempe, AZ, USA PURPOSE The primary objective of this study was to determine the clinical impact and value of neuroradiology reinterpretations by subspecialty neuroradiologists (neuroradiologists whose clinical practices are nearly exclusively devoted to neuroimaging). METHODS All secondary interpretations for CT and MR neuroradiology studies performed outside our institution over a 28-week period in 2010 were retrospectively compared to the primary (outside) interpretation, with interpretive differences recorded. When a patient had more than one examination on the same area reviewed at the same time (such as a head CT and head MR), only one secondary interpretation encompassing all reviewed studies was issued. Clinical notes, pathology and subsequent imaging determined ground truth diagnosis and the clinical impact of any interpretive errors were graded as having high clinical impact if it could lead to an incorrect treatment plan, and graded as medium clinical impact if it could lead to minor delays or unnecessary additional tests. Interpretive comparisons were scored into categories: (1) no difference; (2) incidental findings of no clinical impact; (3) finding not reported; (4) significance of finding undercalled; (5) significance of finding overcalled; (6) finding misinterpreted; (7) multiple error types in one report; (8) unable to determine. RESULTS 266 report comparisons were reviewed on 260 patients, evaluating 33 CT, 226 MR, and 7 CT plus MR examinations. The primary report had 3.8 % (10/266) high clinical impact interpretive errors and 5.2 % (14/266) medium clinical impact errors. Of the 24 high or medium clinical impact outside interpretation errors, 9 (37.5 %) were due to unreported findings, 11 (45.8 %) were due to overcalls, and 4 (16.7 %) were due to a misinterpretation. The subspecialized secondary report had no high clinical impact errors; there were 0.8 % cases (2/266) where the subspecialty interpretation was graded as a medium impact error (1 undercall and 1 overcall). CONCLUSIONS Subspecialty review of neuroradiology imaging exams provides clinical benefit. Failure to report significant findings and ascribing too much significance to findings (overcalls) accounted for more than 80 % of the errors made in the primary interpretation.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Keywords Second interpretations, outside exams, subspecialty interpretations P.1.102 ALTERED AXONAL INTEGRITY OF LOWER LIMB MOTOR TRACTS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A DTI BIOMARKER FOR DIFFERENTIATING LUMBARDRAINAGE RESPONDERS FROM NON-RESPONDERS C. Chen1, S. Chiang2, S. Chung3, H. Kao2 1 Taipei Medical University Hospital, Department of Medical Imaging, Taipei, Taiwan, 2Tri-Service General Hospital, Department of Radiology, Taipei, Taiwan, 3National Taiwan University, Department of Electrical Engineering, Taipei, Taiwan

PURPOSE Gait disturbance is the most common initial symptom in idiopathic normal pressure hydrocephalus (iNPH). The diagnostic workup of iNPH for shunt treatment may include invasive lumbar CSF drainage. We aimed to investigate the diffusional properties of the lower limb motor tracts in iNPH patients by using diffusion tensor imaging (DTI) and to determine whether these tensor parameters can be used as biomarkers to differentiate lumbar-drainage responders from non-responders in iNPH patients. METHODS During the last 4 years period, we prospectively enrolled 25 patients with iNPH and gait disturbance, and 17 age- and sex-matched controls for DTI study. Diffusion tensor metrics of the lower-limb corticospinal tracts (CST) and corpus callosum, including FA values, axial eigenvalues, and radial eigenvalues, were evaluated by using tract-specific analysis. The DTI findings were compared among groups with lumbardrainage responders, non-responders and the control. RESULTS Tract-specific analysis of the lower-limb CST at pontine level showed that axial eigenvalues were significantly increased (P<.01), whereas FA and radial eigenvalues were not significantly altered, in patients with iNPH compared with the control. In corpus callosum, the distended body showed decreased FA and prolonged axial eigenvalues. The nonresponders revealed increased axial eignvalues than that of the responders (p <0.01). ROC analysis showed accuracy 0.898 (p<0.001), and a sensitivity of 100 % and specificity of 100 % at a cutoff value of 0.0018. CONCLUSION Gait disturbance in iNPH is associated with altered axonal integrity in the corups callosum and lower-limb motor tracts. The degree of axonal integrity changes is significantly increased in lumbar-drainage nonresponders than the responders. DTI may potentially be useful in differentiate the responders from non-responders in the diagnostic workup of iNPH patients who might benefit fronm permanent ventriculo-peritoneal shunting treatment. Keywords Normal pressure hydrocephalus, diffusion tensor imaging, lumbar drainage P.1.103 CAROTID INTIMA-MEDIA THICKNESS INCREASE IN SLEEP DISORDERS M. Apaydin1, S.O. Ayik2, M. Varer1, G. Akhan3, S. Peker3, E. Uluc1 1 Department of Radiology, Katip Celebi University Ataturk Education and Training Hospital, Izmir, Turkey, 2Department of Chest Disorders, Katip Celebi University Ataturk Education and Training Hospital, Izmir, Turkey, 3Department of Neurology, Katip Celebi University Ataturk Education and Training Hospital, Izmir, Turkey

Sleep disorders are emerging risk factors for atherosclerosis. Increased carotid intima-media thickness (CCA-IMT) is a surrogate marker of

S115 cardiovascular risk. The aim of the presentstudy was to investigate the relationship betweenCCA-IMT and habitual simple snoring or obstructive sleep apnea syndrome (OSAS) and the other cardiovascularrisk factors. Sleep disorders were diagnosed and staged by polysomnography. Patients were then classified into either habitual simple snoring (n=20, group 1) or OSAS (n=67, group 2), which was subclassified as mildmoderate (n=27) or severe (n=40). CCA-IMT was measured by Bmode ultrasonography. The other major risk factors were investigated. The mean CCA-IMT was 0.65±0.02 mm (mean±SD) in group 1 versus 0.75±0.02 mm in group 2 (p=0.03). Using CCA-IMT >0. 9 mm as the threshold value also yielded significant results between the two groups (p=0.03). The mean CCA IMT did not differ between patients with mild-moderate and severe OSAS, whereas metabolic risk factors and metabolic syndrome (MS) were more prominentin the latter. Age, MS, neck and waist circumference, waist/ hip circumference, and fasting glucose level were higher in patients with CCA-IMT>0,09 mm. CCA-IMT increase was associated with OSAS, but did not correlate with its severity, which could be due to the higher incidence of MS in this group. Keywords Carotid intima-media thickness, obstructive, ultrasonography P.1.104 RADIOLOGICAL FEATURES OF ENCEPHALOPATHY ASSOCIATED WITH E. COLI O111 OUTBREAK IN JAPAN J. Takanashi1, H. Tada2, H. Taneichi3, A. Okumura4, H. Terada1, M. Mizuguchi5 1

Toho University, Sakura Medical Center, Sakura, Japan, 2Saiseikai Narashino Hospital, Narashino, Japan, 3University of Toyama, Toyama, Japan, 4Juntendo University Faculty of Medicine, Tokyo, Japan, 5Graduate School of Medicine, University of Tokyo, Tokyo, Japan PURPOSE To elucidate the clinical and radiological features of encephalopathy associated with Shiga toxin-producing Escherichia coli (STEC) O111. METHODS We reviewed the clinical charts and neuroimaging in 22 patients with neurologic symptoms among 86 patients with STEC O111 infection (34 having hemolytic-uremic syndrome [HUS]) occurring in Toyama and other prefectures in Japan between late April and early May 2011. The day of onset of encephalopathy was defined as day (D) 0. RESULTS Twenty-one (6 males and 15 females, 10 children under 16 years and 11 adults) of the 22 patients were diagnosed as having encephalopathy (24 % and 62 % of STEC O111 infection and STEC O111-HUS patients, respectively). Their neurological symptoms included disturbance of consciousness in 16 patients, delirious behavior in 14, and seizures in 8. Five patients died from D1 to 6 months (D1 to D5 in 4 patients) due to progressive encephalopathy with severe cerebral edema observed on neuroimaging (four patients). Fifteen of the 16 surviving patients clinically recovered completely. Neuroimaging studies revealed symmetrical lesions in the lateral thalamus in 12 patients, including 4 deceased patients, putamen or globus pallidus in 10 (5 deceased patients), external capsule in 9 (5 deceased patients), and dorsal brainstem or cerebellum in 6 (3 deceased patients). The apparent diffusion coefficient (ADC) value in the lateral thalamus was reduced in 4 patients scanned within D7, and normal or increased in 3 patients after D7. On the other hand, ADC in the putamen and external capsule was increased in 3 patients examined on D2, 6, 7, and 10. Spotty lesions in the white matter or basal ganglia suggesting lacunar infarctions were recognized in 5 patients on D6 to 27. CONCLUSION This study adds to our knowledge on the clinical and radiologic features of STEC O111 infection, which was characterized by a high incidence of encephalopathy and a high fatality rate. The characteristic distribution, i.e., symmetrical lesions in the lateral thalamus, basal ganglia,

S116 external capsule, and dorsal brainstem or cerebellum, may provide a radiological clue for the early diagnosis of STEC-encephalopathy, however, which could not predict the neurologic outcome. Keywords Encephalopathy, E. coli O111, infection P.1.105 AMNESTIC SYNDROMES AND LESIONS WITH HIGH DIFFUSION SIGNAL IN THE LIMBIC SYSTEM AND HIPPOCAMPUS – A PICTORIAL ESSAY M. Sarpi, M. Docema, M. Martin, L. Silva, L. Godoy, D. Delgado, H. Lee Hospital Sírio Libanês, São Paulo, Brazil PURPOSE To depict and discuss imaging findings that allow differentiation among the variety of clinical conditions that may course with high diffusion signal in the limbic system and particularly in the hippocampus, acknowledging imaging and anatomic highlights that may lead to the proper diagnosis in conjunction with the patient’s clinical history and symptoms. METHODS Literature review and exemplification by confirmed clinical cases with magnetic resonance imaging (MRI) of the most frequent diseases – acute ischemic stroke, transient global amnesia (TGA), status epilepticus, inflammatory and infectious conditions (limbic encephalitis) and anoxic encephalopathy – including a rare case of anterior commissure and anterior columns of the fornix stroke. Some of these cases have follow-up imaging that will be also presented. Anatomic and imaging details will be discussed offering tools for the radiologist to work up the differential diagnosis for these cases in correlation to clinical data. Particularly regarding TGA we will also exemplify the importance of an accurate examination technique (specific DWI protocol with higher B values and thinner slices) to improve the detection of lesions, even in a short period between clinical onset and MRI acquisition. RESULTS All cases to be demonstrated represent confirmed cases of pathologies that involve the limbic system and specially the hippocampus. CONCLUSIONS This pictorial essay will demonstrate the importance of familiarization with the limbic system clinical syndromes and their imaging presentation, correlated with the variety of causes found in literature and clinical practice. Our goal will be, through clinical cases, to highlight the key points that should be evaluated by the radiologist, leading to an effective contribution for the differential diagnosis in these cases. Keywords Amnestic syndromes, high diffusion signal, limbic system and hippocampus

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Kodaira, Japan, 5Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan PURPOSE Corticobasal degeneration (CBD) is a rare neurodegenerative disorder characterized by distinctive clinical manifestations including asymmetric akinetic-rigid syndrome and higher cortical dysfunctions. In the clinical aspect, it can be impossible to differentiate CBD from progressive supranuclear palsy (PSP) due to overlaps in the similar clinical course and neurological findings. These disorders can also reveal similar atrophic patterns in the midbrain tegmentum and subcortical frontal lobe white matter (WM). Although previous studies have reported the predominant atrophy of the midbrain in PSP and subcortical frontal WM in CBD, data on the utility for the differentiation by these findings are scant. The purpose of this study is to compare the utility of the structural WM atrophy in the differentiation between CBD and PSP. METHODS We retrospectively reviewed clinically diagnosed 18 CBD and 33 PSP patients, and 32 age-matched controls, who had undergone 3D T1weighted magnetic resonance imaging. We randomly divided CBD and PSP patients into two groups. For the first patients group, we first obtained segmented WM images using statistical parametric mapping 8 (SPM8) plus diffeomorphic anatomic registration through exponentiated Lie algebra. Second, with the first patients group, a target volume of interest (VOI) for disease-specific atrophy was determined using group analyses of WM volume between patients group and normal control with a threshold at a cluster false discovery rate of p<0.001 for the multiple comparison correction. Third, we then evaluated the usefulness of these VOIs for differentiating between remaining CBD and PSP patients in the second group. Z score values in these VOIs were used as the determinant in receiver operating characteristic (ROC) analyses. RESULTS Specific target VOIs for CBD were determined in the bilateral frontal subcortical WM including the precentral gyrus. Specific target VOIs for PSP were determined in the midbrain and pontine tegmentum. In the ROC analyses, the target VOIs of CBD revealed higher area under the ROC curves than that of PSP (0.78 vs 0.51). CONCLUSIONS Bilateral frontal WM volume loss demonstrated the higher power for differentiating CBD from PSP. This VOI analysis may be useful for the diagnoses of CBD and PSP pathologies in the parkinsonian syndrome. Keywords Corticobasal syndrome, voxel based morphometry, white matter P.1.107 BASILAR ARTERY HYPOPLASIA AND PERSISTENCE OF CAROTID-VB COMMUNICATIONS

P.1.106 THE UTILITY OF WHITE MATTER VOLUME LOSS ANALYSIS USING SPM8 PLUS DARTEL IN THE DIFFERENTIATION BETWEEN CORTICOBASAL DEGENERATION AND PROGRESSIVE SUPRANUCLEAR PALSY

D. Quiñones1, A. Mas Bonet2, C. Andreu1, M. Picado2, A. Moll2, P. Jimenez-Arribas2, S. Miralbés2

K. Sakurai1, E. Imabayashi1, A. Tokumaru1, S. Hasebe1, S. Murayama2, M. Takao2, K. Kanemaru3, S. Morimoto3, H. Matsuda4, Y. Shibamoto5

PURPOSE Basilar hypoplasia is a frequent finding nowadays in noninvasisve MRI, MRA and CTA exams. The exact definition of basilar hypoplasia is not well established. We considered basilar hypoplasia when the diameter of the basilar trunk was inferior to either posterior cerebelar arteries, usually below 2 mm. The most frequent presentation of basilar hypoplasia is with persistent fetal origin of the posterior cerebral arteries and hypoplasia of the P1 segments (bilateral in 8 %). Congenital communications between

1 Department of Diagnostic Radiology, Tokyo Metropolitan Medical Center of Gerontology, Tokyo, Japan, 2Department of Neuropathology (the Brain Bank for Aging Research), Tokyo Metropolitan Medical Center of Gerontology, Tokyo, Japan, 3Department of Neurology, Tokyo Metropolitan Geriatric Hospital, Tokyo, Japan, 4Integrative Brain Imaging Center, National Center of Neurology and Psychiatry,

1 Hospital Del Rosario, Madrid, Spain, 2Hospital Son Espases, Palma De Mallorca, Spain

Neuroradiology (2013) 55 (Suppl 1):S15–S159 the anterior carotid arteries and the posterior vertebro-basilar system may occur at 5 locations: posterior communicating, trigeminal, otic, hypoglossal and proatlantal type I or II arteries. METHOD A retrospective review of reports from MRI, MRA, and CTA with the diagnosis of Basilar Hypoplasia was performed in two hospitals during the last 3 years. RESULTS The occurrence of bilateral persistent embryologic origin of de posterior cerebral arteries from the carotid arteries was associated with terminal basilar hypoplasia in 50 cases. Trigeminal artery persistence was documented in 18 cases, and we found a female predominance, but no dominant laterality. Associated anomalies were: Aneurysms (3), fenestrations (1), ischemia, nerve compresion or neuralgia, MAV or PHACES. We did not find other congenital anastomosis between the carotid and basilar systems. In the case of aneurysms the abnormal anatomy presents challenging problems with vascular approach for percutaneous embolization. CONCLUSIONS Basilar hypoplasia may de related to posterior fosa vascular insuficiency. Persistent fetal origin of both posterior cerebral arteries is the most common association. Carotid-Basilar abnormal connections occur in up to 1 % of the population, and the persistent trigerminal artery is the most frequently encountered. When detecting basilar hypoplasia the radiologist must search for abnormal connections between the anterior and posterior intracranial arteries, specially if sellar or skull base surgery is planned, and recommend complementary noninvasive vascular imaging. Keywords Basilar artery hypoplasia, trigeminal artery, persistent fetal origin of PCA P.1.108 NEUROCYSTICERCOSIS FOR DUMMIES J. Nair1, J. Chankowsky1, C.I. Torres1, S. Jaggi2, I. Talwar2, P. M. Parizel3, R. Del Carpio O'Donovan1, J. Beegom Mansoor4 1 Dept of Radiology, Montreal General Hospital, McGill University, Montreal, Canada, 2Dept of Radiology, Bombay Hospital Institute of Medical Sciences, Mumbai, India, 3Dept of Radiology, University of Antwerp, Antwerp, Belgium, 4Baraha Hospital, Ministry of Health, Dubai, United Arab Emirates

PURPOSE

1) Revisit the life cycle of Taenia solium. 2) Review in detail characteristic imaging findings in various stages of its evolution especially in the brain parenchyma.

3) Review of less common locations. 4) Emphasize on the Computed Tomography(CT) and Magnetic Resonance Imaging (MRI) findings in patients with previously calcified lesions,presenting with seizures. METHODS 15 patients with recent history of seizures were evaluated using CT (Non-contrast and contrast enhanced examination) and MRI using standard sequences including T1, T2,FLAIR (Fluid Attenuated Inversion Recovery),DWI (Diffusion Weighted Imaging),GRE (Gradient Echo) and Post-Contrast T1 sequences in multiple planes.In addition 3D FIESTA sequence was also added to the routine sequences. 5 patients from endemic areas who presented with first-time seizures or recurrent seizures after a five year period considered 'seizure-free “were also evaluated using the same standard sequences.

S117 RESULTS Characteristic Imaging Findings in various stages:

1) VESICULAR STAGE:

2)

3)

4)

CT:CSF density cystic lesion with no perilesional edema nor contrast enhancement. Scolex appreciated as hyper attenuating rounded structure. MRI: T1W-hypo intense and T2W-hyperintense lesion with discrete hyper intense scolex seen as hole in dot appearance but no perilesional edema nor enhancement. COLLOIDAL-VESICULAR STAGE: CT:Cystic lesion with hyper dense fluid relative to CSF, associated perilesional edema and contrast enhancement. MRI: T1W- iso to hyper intense and T2W- hyper intense cystic lesion with peripheral enhancement/edema. GRANULAR NODULAR STAGE: CT:Cystic lesion with minimal residual perilesional edema and thick but faint peripheral enhancement. MRI: Iso intense to hypo intense on T2W. Target or Bull’s eye appearance. Retraction of cyst wall with diminished perilesional edema, thick but faint ring enhancement. NODULAR CALCIFIED STAGE: CT:Calcified nodule with no perilesional edema nor contrast enhancement. MRI: Signal void on T2W,best appreciated on Gradient echo sequence.

IN RELAPSING CASES Non-contrast-enhanced CT: Nodular calcified lesion / lesions surrounded by a hypo attenuating halo, with effacement of the adjacent cortical sulci, consistent with vasogenic edema. MRI:In addition to the vasogenic edema, demonstrates varying degree of peripheral enhancement of the calcified lesions. CONCLUSION Reviewing the imaging findings in various stages of neurocysticercosis helps to have high index of suspicion in the correct clinical background. Clinicians and radiologists must be made familiar to the fact that patients with calcified lesions,assumed to have resolved may present with late-onset symptoms Keywords Neurocysticercosis, seizures, calcified P.1.109 ANALYSIS OF CSF FLOW DYNAMICS USING CSF FLOW VOID PHENOMENON AND PHASE CONTRAST CINE MRI IN NORMAL PRESSURE HYDROCEPHALUS COMPARED TO SUBCORTICAL VASCULAR DEMENTIA AND HEALTHY VOLUNTEER C. Wirojtananugoon, B. Hooncharoen, J. Laothamatas, S. Chansirikarnjana Ramathibodi Hospital, Mahidol University, Bangkok, Thailand BACKGROUND AND PURPOSE Diagnosis of normal pressure hydrocephalus (NPH) is important, because it is one of the few treatable causes of dementia. Subcortical vascular dementia can have NPH like symptoms and large ventricles as a result of brain atrophy. The aim of the study is to compare CSF flow dynamics in NPH, subcortical vascular dementia and healthy volunteer. MATERIALS AND METHODS We analyse CSF flow dynamics at the cerebral aqueduct using phase contrast cine MRI and CSF signal void on FSE T2W images in 9 patients with NPH, 6 patients with subcortical vascular dementia , and 13 normal volunteers in Ramathibodi hospital during February 2011 – January 2012.

S118 RESULTS In NPH group, 5 (55.6 %) have strong CSF flow void, 4 (44.4 %) have moderate CSF flow void at the cerebral aqueduct. None of NPH group has weak CSF flow void at the cerebral aqueduct. In subcortical vascular dementia group, 4 (66.7 %) have weak CSF flow void, 2 (33.3 %) have moderate CSF flow void. None of subcortical vascular dementia has strong CSF flow void at the cerebral aqueduct. In normal volunteer group, 5 (38.5 %) have weak CSF flow void, 8 (61.5 %) have moderate CSF flow void at the cerebral aqueduct. In NPH group, range and mean of peak velocity is 2.5-15.2 cm/s and 9.9 cm/s during systole, 5.0-12.8 cm/s and 9.7 cm/s during diastole. In subcortical vascular dementia group, range and mean of peak velocity is 1.1-4.8 cm/s and 3.0 cm/s during systole, 1.25.1 cm/s and 3.6 cm/s during diastole. In normal volunteer group, range and mean of peak velocity is 4.2-12.6 cm/s and 8.8 cm/s during systole, 2.6-13.2 cm/s and 7.5 cm/s during diastole. Using statistical analysis, there is significant difference of CSF peak velocity between normal pressure hydrocephalus group and subcortical vascular dementia group (P-value=0.001). CONCLUSIONS Analysis of grading of CSF flow void on FSE T2W images and CSF peak velocity using phase contrast cine MRI at the cerebral aqueduct can be helpful to differentiate between normal pressure hydrocephalus and subcortical vascular dementia. Keywords Normal pressure hydrocephalus, subcortical vascular dementia, CSF flow dynamics P.1.110 MAGNETIC RESONANCE IMAGING IN DIAGNOSIS OF VASCULITIS OF INTERNAL CAROTID, VERTEBRAL AND BASILAR ARTERIES E. Seliverstova, L. Dobrynina, M. Krotenkova, L. Kalashnikova Research Center of Neurology, Russian Academy of Medical Sciences, Moscow, Russia PURPOSE Refining of magnetic resonance imaging (MRI) study protocol using 1.5-T scanner in patients with clinical suspicion of vasculitis of internal carotid and/or vertebral arteries, and/or basilar artery. METHODS We studied nine patients (mean age 36.5±10.2 years) with clinical suspicion of vasculitis of internal carotid and/or vertebral arteries, and/or basilar artery. MRI was performed using a 1.5-T scanner (Avanto, Siemens, Erlangen, Germany). Vascular patency and abnormalities of vessels’ wall were studied using 3D time-of-flight magnetic resonance angiography (3D TOF MRA) with assessing vessels from an aortic arch to Willis’ Circle. In order to evaluate arterial wall T1fat sat, T1dark blood, T2FLAIR images in axial, coronal and perpendicular to vessel’s section views were obtained in all patients before and after intravenous 0.5 M gadolinium enhancement. Thickened vessel’s wall with lumen narrowing or arterial occlusion and/or distribution of gadolinium enhancement in thickened vessel’s wall were defined as signs of inflammation in vessel’s wall. We assessed localization, length, and severity of revealed abnormalities comparing with the same segments of contralateral arteries. RESULTS Inflammation signs in internal carotid arteries were revealed in seven patients (77.8 %); vertebral and basilar arteries were affected in two patients (22.2 %). The most appropriate MRI sequences for revealing inflammation in the vessel’s wall were T1fat sat and T1dark blood.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSIONS Evaluating the zone from an aortic arch to Willis’ Circle while performing 3D TOF MRA facilitates searching for abnormal segment of an artery. Inclusion of T1 fat sat and T1dark blood sequences while performing the MRI study on 1.5-T scanner with gadolinium enhancement improves visualization of probable inflammatory signs in internal carotid, vertebral and basilar arteries’ wall in case of clinical suspicion of vasculitis. Keywords Vasculitis, MRI, 3D TOF MRA P.1.111 GOSSYPIBOMA - AN UNUSUAL INTRACRANIAL MIMIC IN A CHILD E. Ryan, N. Adams, P. Brennan, A. O'Hare, M. Thornton, S. Looby Department of Neuroradiology, Beaumont Hospital, Dublin, Ireland PURPOSE Gossypibomas are foreign body reactions arising from retained swab material and appearing as an enhancing lesion on MRI. Abscess formation can occur in the acute setting, while seizures have been described in the chronic setting. We present a case of a gossypiboma occurring in a child following resection of a pilocytic astrocytoma (PCA), resulting in a diagnostic and management conundrum. MATERIALS AND METHODS We performed a retrospective review of the clinical and operative course of this 3 year-old boy. MR imaging and digital subtraction angiography were reviewed by a subspecialist neuroradiologist and pathological correlation was provided by a subspecialist neuropathologist. RESULTS A 3 year-old boy underwent near-total surgical resection of a PCA involving the left posterior limb of the internal capsule and the posterior lentiform nucleus. Immediate post-operative imaging showed enhancement at the resection site indicating minimal tumour residuum but was otherwise unremarkable. Follow-up imaging demonstrated a small new focus of enhancement separate from the tumour but along the surgical tract, adjacent to the left middle cerebral artery. Digital subtraction angiography excluded a pseudoaneurysm. Both regions of enhancement enlarged on subsequent imaging and surgical resection was performed. Histology of the lesion adjacent to the left MCA showed exuberant foreign body giant cell reaction, representing a gossypiboma. CONCLUSION We present sequential imaging and histopathology of a postoperative intracranial enhancing gossypiboma mimicking tumour recurrence. In cases of unexpected apparent tumour recurrence, particularly removed from the resection cavity, this is a rare but important consideration. Keywords Gossypiboma P.1.112 NON-TRAUMATIC INTRA CEREBRAL HEMORRHAGE - A PICTORIAL ASSAY J. Nair1, S. Jaggi2, S. Shah2, J. Chankowsky1, C.I. Torres1, I. Talwar2, R. Del Carpio O'Donovan1, J. Beegom Mansoor3 1 Department of Radiology, Montreal General Hospital, Mcgill University, Montreal, Canada, 2Department of Radiology, Bombay Hospital, Mumbai, India, 3Baraha Hospital, Ministry of Health, Dubai, United Arab Emirates

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PURPOSE 1) To demonstrate imaging findings in non-traumatic pathologies that result in intra cerebral hemorrhage 2) To distinguish primary causes from secondary pathologies causing intra cerebral hemorrhage based on imaging. METHODS 500 patients who presented to the emergency with focal neurological deficit , headache, altered consciousness, seizure, nausea, vomiting and other acute symptoms were evaluated initially by Non-Contrast Computed Tomography(CT) and then by Magnetic Resonance Imaging ( MRI), CT Angiography/ Digital Subtraction Angiography (DSA) based on the initial CT findings. RESULTS Hypertension, Cerebral Amyloid Angiopathy( CAA), Hemorrhagic transformation of ischemic stroke, Aneurysmal Subarachnoid hemorrhage, Vascular malformations, Venous Thrombosis, Neoplasia – Primary, Metastases were the major causes of intra cerebral hemorrhage in most of our patients. Other causes included Vasculitis, Vasculopathy, Vasospasm and Anticoagulant therapy, though to a very small extent.. Primary causes such as Hypertension or CAA could be differentiated from secondary pathologies, such as Arterio-venous malformations, Coagulopathies, Cerebral venous and sinus thrombosis CONCLUSION Multi-modality approach, excellent co-ordination between the radiologist and clinician forms the key to determine cause of most spontaneous Intra cerebral hemorrhage , although in some patients the cause remains indeterminate despite an extensive clinical and diagnostic workup in the acute and chronic phase. Keywords Non-traumatic, hemorrhage, intracerebral P.1.113 APPROACHING THE TRIGEMINAL NERVE. OUR EXPERIENCE IN CT-GUIDED PROCEDURES J. Ortiz1, J. Ocampo1, J. Abreu1, J. Moyano1, J. Tejada2, N. Useche1, S. Bermudez1 1

Hospital Universitario Fundacion Santafe de Bogota, Bogota, Colombia, 2 IU Health University Hospital, Indianapolis, IN, USA

PURPOSES To show our experience approaching the trigeminal nerve pathology with a minimally invasive technique using computed tomography (CT)guided procedures.. Describe the anatomy, anatomical variations, technique and different approaches to the foramen ovale, which are prerequisites for the performance of these procedures MATERIALS AND METHODS We evaluated retrospectively 7 patients, who came to our institutions for a biopsy or for a peripheral nerve block and radiofrequency ablation of the trigeminal nerve guided by CT. We reviewed the anatomy, anatomical variations, the different approaches, as well as posible complications derived from the procedures. RESULTS We reviewed a total of 3 biopsies and 4 trigeminal nerve blocks and radiofrequency ablations. Patients were adults between 18 and xx years old. 6 subzigomatic approaches and 1 paramaxilar approach were performed without any major complication. CONCLUSIONS Minimally invasive CT-guided procedures of the fifth cranial nerve are very udeful for the treatment of the trigeminal neuralgia and for the histopathologic diagnosis of masses. These skull base lesions are difficult for the head and neck surgeon and for the neurosurgeon, to access safely. Thorough knowledge of the anatomy, anatomical variations technique

S119 and different approaches to the foramen ovale are prerequisites for the performance of these procedures and to avoid potential complications. Keywords Trigeminal nerve, CT guided procedure, approaches of the trigeminal

Advanced/new imaging modalities P.1.114 D I S R U P T I O N O F D E FA U LT N E T W O R K A C T I V I T Y IN ACUTE STROKE PATIENTS WITH EARLY IMPAIRMENT IN CONSCIOUSNESS Y. Tsai1, H.H. Weng2, B. Biswal3, C.P. Lin1, R. Yuan3 1 National Yang Ming University, Department of Biomedical Imaging and Radiological Sciences, Taipei, Taiwan, 2Chang Gung Memorial Hospital at Chiay, Department of Diagnostic Radiology, Chiayi, Taiwan, 3New Jersey Institute of Technology, Department of Biomedical Engineering, Newark, NJ, USA

PURPOSE Impairment in consciousness is frequent in acute stroke patients and is correlated with outcome after stroke. The mechanisms for the impairment of consciousness are not fully understood and little is known about brain activity and connectivity change in acute stroke patient with impairment of consciousness. Spontaneous low frequency fluctuations of the blood oxygen level dependent signal and in brain activity are the keys to determining correlated activity between brain regions and defining resting state networks. Amplitude of spontaneous low frequency fluctuations (ALFFs) and regional homogeneity (ReHo) of the blood oxygen level dependent signal and in brain activity is associated with regional brain activity. METHODS Seventeen consecutive patients of first-ever stroke with early impairment of consciousness were enrolled in this study. Resting-state functional magnetic resonance imaging (MRI) scans were acquired within 24 hours after stroke onset. Nineteen healthy subjects were also enrolled. The functional MRI data processing was accomplished using Analysis of Functional NeuroImages (AFNI) software (http://afni.nimh.nih.gov/afni; version: Jan 2012) and FMRIB Software Library (FSL) (http://www.fmrib.ox.ac.uk/fsl/; version: 4.1.8). ALFFs and ReHo of the blood oxygen level dependent signal were estimated to detect regional brain activity. The connectivity of default mode network (DMN) was also calculated with spatial independent component analysis method. RESULTS Decreased ALFFs and ReHo intensity among stroke patients with early impairment of consciousness in precuneus and posterior cingulate cortex regions were observed. The significant reduction in the DMN was also observed where there was a reduction in the number of active voxels (22.1 %, P=0.000). There are significant correlations between DMN voxel number and the Glasgow Coma Scale at time of MRI scan (R=0.487; P=0.004) and at time when patient discharged (R=0.604; P=0.000). CONCLUSIONS The precuneus and posterior cingulate cortex are the key regions of arousal and consciousness. Decreased activity among these regions was observed in unconscious patients in this study. The connectivity of DMN is related maintaining of consciousness and was correlated with clinical conscious scale in this study. The resting state functional MRI is a feasible tool for evaluation acute stroke patients with early impairment of consciousness and the

S120 detailed mechanisms and implications of these brain activity and network changed will require further investigation. Keywords Resting state fMRI, stroke, consciousness P.1.115 VALUE OF FOUR-DIMENSIONAL MR ANGIOGRAPHY AT 3.0 T COMPARED TO DSA FOR THE FOLLOW-UP OF TREATED BRAIN ARTERIOVENOUS MALFORMATIONS S. Soize1, K. Kadziolka1, F. Bouquigny1, C. Portefaix2, L. Pierot1 1

Hospital Maison Blanche, Department of Radiology, Reims, France, CReSTIC SIC EA3804, University of Reims, Reims, France

2

PURPOSE Four-dimensional contrast-enhanced magnetic resonance angiography (MRA) at 3.0 T has a very good agreement with digital substraction angiography (DSA) regarding brain arterio-venous malformation (bAVM) diagnosis and classification. The purpose of this study is to evaluate it usefulness for the follow-up of treated cerebral arteriovenous malformations. METHODS This retrospective study analyzed patients with previously treated bAVM. Each patient underwent both DSA and 4D MRA at least 1month after last treatment. Both examinations were not more distant than a month and without intercurrent treatment. MRA examinations were performed at 3 T using a 4D-TRAK sequence, which permitted an overall accelerating factor of 40 with the combination of CENTRA keyhole and SENSE techniques. Examinations were compared by two independent and experienced readers. Studied endpoints were the presence of residual nidus and/or early venous drainage. Disagreements were resolved by a third reader. RESULTS Between May 2008 and February 2013, 37 patients, 22 men and 15 women, with mean age of 42±17 year-old completed the follow-up protocol. They have been previously treated by: embolization then radiosurgery (35 %), embolization (24 %), radiosurgery (22 %), surgery (8 %) and surgery then embolization or radiosurgery (11 %). Thirtythree (89 %) of bAVM were supra-tentorial. The pair of examinations was acquired meanly 32±26 months after last treatment. The statistical analysis is in process. Interobserver and intermodality agreements with respect to residual nidus and early venous drainage were determined using the kappa statistic test. Quality of the 4D MRA images was also evaluated. CONCLUSIONS The study will answer the usefulness of 4D MRA for the follow-up of brain AVM. Keywords Arteriovenous malformation, four-dimentionnal MRA, follow-up P.1.116 DIFFUSION TENSOR TRACTOGRAPHY IN MESIAL TEMPORAL SCLEROSIS SURGERY: AN INSTITUTIONAL EXPERIENCE D. Siu1, X.L. Zhu2, Y.X. Wang1, J.M. Abrigo1, J.C.S. Leung3, C.H.K. Mak2, W.S. Poon2 1

Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Hong Kong, Hong Kong, 2Chinese University of Hong Kong, Division of Neurosurgery, Department of Surgery, Hong Kong, Hong Kong, 3Chinese University of Hong Kong, Department of Ophthalmology, Hong Kong, Hong Kong BACKGROUND In patients with mesial temporal sclerosis underging anterior temporal lobectomy (ATL) plus amygdalohippocampectomy, the anterior portion

Neuroradiology (2013) 55 (Suppl 1):S15–S159 of the optic radiation, also known as Meyer’s loop, can be damaged resulting in homonymous superior quadrantanopia. Magnetic resonance diffusion tensor tractography (DTT) can visualize the Meyer’s loop and facilitate surgical planning to lower the risk of post-operative visual field defect. In our institution, we have incorporated DTT in our epilepsy imaging protocol since 2009. The clinical outcome of patients after ATL with and without pre-operative DTT-guidance is compared. METHODS All patients who underwent ATL for mesial temporal sclerosis were included in the study and grouped as standard ATL (without preoperative DTT) and modified ATL (with pre-operative DTT). Diffusion tensor imaging was performed on a 3 T MRI using a single-shot spin echo echo-planar-imaging sequence, and ATL resection margins were tailored according to Meyer’s loop. All patients received visual field assessment by an ophthalmologist. RESULTS Thirty-eight subjects were included in the study. In 23 patients who received standard ATL, 70 % (16/23) had visual field defect. In 15 patients who underwent modified ATL, 33 % (5/15) had visual field defect, 3 of which had incomplete medial hemianopia. Both groups had acceptable seizure outcomes after surgery; 86.7 % (13/15) of modified ATL patients became seizure-free. CONCLUSION Diffusion tensor tractography is useful in surgical planning for epilepsy surgery and lowers the risk of visual field defect. Keywords Diffusion tensor tractography, anterior temporal lobectomy, Meyer's loop P.1.117 EVALUATION OF CEREBRAL BLOOD FLOW USING PASL IN HEALTHY VOLUNTEERS E. Shults1, I. Proinin1, L. Fadeeva1, A. Celik2, V. Kornienko1 1

Burdenko Neurosurgery Instittute, Neuroradiology, Moscow, Russia, Clinical Science Development Group, GE Healthcare, Istanbul, Turkey

2

PURPOSE ASL-perfusion is non-contrast method of assessing the cerebral blood flow (CBF) and alternative technology compare to CE CT and MRI perfusion. The main advantage of ASL is its non-invasive nature. The implementation of this technology in clinical setting allows monitoring CBF changes noninvasively in cases with various cerebral pathology. The lack of reliable information about normal CBF values in different age groups was caused of using ASL in our research. METHODS 43 healthy volunteers (without neurological disorders) were studied. They were divided into two age groups: 21–40 years (G1) and 41– 60 years (G2). The ASPECTS program served as a base for the measurement of hemodynamic parameters. Also additional zones of interest were added to our study – in total 15 zones for right (r) and left (l) hemispheres. RESULTS Following average values were received for large cortical areas of MCA territory (M2), ACA (A1, A2), PCA (P1, P2), white matter (WM) and hemispheres (H) on the both sides: G1 - rM2 = 61,68 ± 8,59, l M 2 = 6 3 , 4 9 ± 8 , 2 7 ; r A 1 = 6 8 , 9 3 ± 11 , 7 1 , l A 1 = 6 8 , 1 4 ± 6 , 8 ; rA2 = 67,49 ± 12,46, lA2 = 70,64 ± 10,92; rP1 = 60,23 ± 12,91, l P1 = 6 7, 0 3 ± 8 , 8 6 ; r P2 = 6 0, 7 1 ± 11 , 4 7 , l P2 = 6 6 , 9 8 ± 8 , 7; rWM = 21,56 ± 2,86, lWM = 21,06 ± 2,21; rH = 45,94 ± 6 35, lH = 47,26 ± 6,31; G2 - rM2 = 52,24 ± 9,19, lM2 = 56,78 ± 9,9; rA1 = 57,55 ± 11,87, lA1 = 59,48 ± 10,78; rA2 = 53,87 ± 12,87, lA2 = 57,82 ± 19,00; rP1 = 52,45 ± 10,72, lP1 = 54,17 ± 15,06; rP2 = 52,72 ± 16,51, lP2 = 57,81 ± 16,00; rWM = 23,40 ± 2,14, lWM=25,21±2,98; rH=44,08±9,17, lH=41,48±8,49.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 CONCLUSIONS The obtained results demonstrate the differences of perfusion parameters between the age groups of healthy volunteers. It can be useful as a reference point for hemodynamic parameters evaluation in followed studies for patients with cerebrovascular diseases and brain tumors. Keywords ASL-perfusion, cerebral blood flow, normal brain P.1.118 THE USE OF fMRI IN CLINICAL PRACTICE BEYOND PRESURGICAL PLANNING: IMAGINARY, LANGUAGE AND OLFACTORY PARADIGMS H. Felgueiras1, P. Branco2, T. Santos1, H. Morais1, M. Veloso1, J. Spratley2,3, P. Abreu2,3, D. Seixas1,2 1

Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova De Gaia, Portugal, 2Faculty of Medicine of Porto University, Porto, Portugal, 3 Centro Hospitalar São João, Porto, Portugal FMRI has been used in clinical practice mostly to plan the excision or biopsy of intracranial lesions, hoping to avoid damage to eloquent areas of the brain. However, informed by Neuroscience, fMRI has the potential to be of interest in many other clinical situations, as beautifully exemplified by recent work in patients in vegetative state. Our purpose was to illustrate fMRI use in clinical practice beyond presurgical planning. We reviewed our database, retrieving three cases. The first case was 51 year-old male that had a spinal cord trauma, resulting in paraplegia and a neuropathic pain syndrome affecting his right lower limb. Motor cortex stimulation was proposed, after other treatments had failed. Because the trauma had been ten years before, neuronal plasticity phenomena could have changed the expected topography of the primary motor cortex for the lower limbs. FMRI was used to locate the area with an imaginary paradigm. The second case describes a 70 year-old patient with a sudden episode of stuttering and apparent repetition impairment. After excluding other causes, the hypothesis of a psychogenic episode or seizure remained. Structural and language fMRI with conjunction analysis were performed hoping to contribute for the diagnosis. The last case was an 8 year-old girl diagnosed with anosmia, with history of head trauma at 12 months of age. However, hyposmia was suspected when she started to report few smell sensations with incongruent testing. Olfactory fMRI using two odorants and a volumetric study of the olfactory bulbs were performed, to further characterise the presence/absence of smell. Activity in the olfactory cortex, anterior commissure, piriform cortex, amygdala and orbitofrontal cortex was demonstrated, although asymmetrical; asymmetry in the volume of the olfactory bulbs was also found. In selected cases, fMRI with unconventional paradigms and post processing can be helpful in the clinical setting in understanding physiopathology, diagnosis and guiding treatment of a broader group of diseases. It is important for the Neuroradiologist to be involved in Neuroscience research to be able to bring to the clinical practice different imaging approaches to the neurological or neurosurgical patient. Keywords fMRI P.1.119 ARTERIAL SPIN LABELING, DIFFUSION-TENSOR IMAGING AND FDG-PET IN FOCAL CORTICAL DYSPLASIA S. Sarria Estrada1, M. Toledo2, G. Cuberas-Borrós3, C. LorenzoBosquets3, C. Vert1, C. Auger1, A. Rovira1 1

Magnetic Resonance Unit, Radiology Department, Vall d´Hebrón University Hospital, Barcelona, Spain, 2Epilepsy Unit, Neurology Department, Vall d´Hebrón University Hospital, Barcelona, Spain, 3 Nuclear Medicine Department, Vall d´Hebrón University Hospital, Barcelona, Spain

S121 PURPOSE This study aimed to evaluate the diagnostic yield of arterial spin labeling (ASL) perfusion imaging and differences in the anisotropy fraction in focal cortical dysplasia. METHODS Five patients with epilepsy secondary to focal cortical dysplasia were identified by 3 T MR. Interictal ASL, diffusion tensor Imaging (DTI) and 18 F-fluorodeoxyglucose positron emission tomography (FDGPET) were performed on all of them. Lesion volume was determined in the structural T1 sequences. Relative cerebral blood flow (CBF) differences were studied by asymmetry index by comparing the region of interest with a mirror focus in the opposite hemisphere. Anisotropy fraction and FDG-PET signal analysis of the lesions were compared using the same method. RESULTS Focal cortical dysplasia volumes ranged from 0.43 to 1.9 cc. (three located in the temporal lobes and two in the frontal lobes). The asymmetry index for the ASL showed focal hypoperfusion over the cortical dysplasia in three out of five patients. Such findings correlated with the decreased metabolism observed in three of the patients by FDG-PET. The remaining two patients with normal FDG-PET metabolism did not show hypoperfusion in ASL. Anisotropy fraction results did not correspond with these lesions. CONCLUSION Focal cortical dysplasias demonstrated hypoperfusion in ASL maps matching the areas of hypometabolism in FDG-PET Imaging. ASL has the potential to be an important sequence of localizing the focal cortical dysplasias in patients with epilepsy. Keywords Dysplasia, ASL, PET P.1.120 ARTERIAL SPIN LABELING AND ITS APPLICATIONS IN PEDIATRIC CENTRAL NERVOUS SYSTEM. PICTORIAL REVIEW A. Sanchez-Montanez, J.P. Salazar, I. Delgado, J.F. Corral, M. Fernandez, E. Vazquez 1

Vall D'Hebron University Hospital, Diagnostic Imaging, Barcelona, Spain PURPOSE To review arterial spin labeling (ASL) methodologies and clinical applications, while focusing on pediatric neuroscience. METHODS In our institution we have the opportunity of using ASL while performing 3 T MR for more than 3 years. We review some examples of ASL applications in different clinical neuropediatrics scenarios: stroke, hypoperfusion syndromes, PRES, infection, epilepsy, migraine, encephalopathy, oromotor disorders, neurooncology. RESULTS ASL provides an endogenous and completely noninvasive tracer for the quantification of regional cerebral blood flow (CBF) with magnetic resonance imaging (MRI). ASL also plays a role as a biomarker of regional brain function in basic and clinical neuroscience. We should be awared about nephrotoxicity of magnetic resonance contrast media, and about renal immadurity in infants under one year of life. Radiologists must try to administrate gadolinium just when it is necessary and when additional informational will be acquired. CONCLUSIONS ASL should be acquired as part of a multimodal MRI examination in our daily clinical practice because it may help us in the diagnosis of some pathologies and in the approach to a huge differential diagnosis.

S122

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Department of Radiology, Siriraj Hospital, Bangkok, Thailand, 2Department of Physical Therapy, Siriraj Hospital, Bangkok, Thailand, 3 Department of Radiation Technique, Faculty of Technical Medicine, Siriraj Hospital, Bangkok, Thailand

Its characteristics as a noninvasive, easy and fast method, make ASL a very important utility in pediatric MR imaging. Keywords Arterial spin labeling, central nervous system, pediatrics

1

P.1.121 DIFFUSION TENSOR MR IMAGING AND TRACTOGRAPHY AT 3.0 T: ANATOMY AND CLINICAL APPLICATIONS

PURPOSE The arcuate fasciculus (AF) is great important to language processing in human and using of AF for lateralization of the dominant hemisphere in Thai speakers with Thai mother tongue language has not been studied. The purpose of this study was to demonstrate any possibility that AF (by DTI) could be used to lateralize the dominant hemisphere in nativeThai language, using relative fiber density (RFD) , fractional anisotropy (FA) and asymmetry index (AI) in relation to functional hemispheric language lateralization from functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS Ten normal official Thai speakers with Thai mother tongue language (5 male, 5 female, mean age 24.9 years; range 22–37 years) were studied with diffusion tractography (DTI) by 3 T MRI. The two ROI methods were used for tract the arcuate fasciculus, bilaterally. The RFD , FA and AI were analyzed to determine the dominant hemisphere. Comparison of the lateralization from fMRI language paradigm was done. RESULTS The RFD lateralize to the right were found in 5 and to the left in 3 subjects. The FA was slightly lateralized to the left in all subjects, However, the AI lateralization to the right was found in 5 subjects, to the left in 3 subjects. The lateralization from the fMRI language paradigm using visual analysis of all subjects were to the left. The anterior end of the AF tract was at par opercularis in 6 subjects, par triangularis in 3 subjects and middle frontal gyrus in 5 subjects. The posterior end of the AF was at superior temporal gyrus in 7 subjects, middle temporal gurus in 9 subjects and par angularis in 4 subjects. When fusion with the fMRI using word paradigm , the termination of the AF was not correlated with activation from fMRI in 6 subjects, and in 7 subjects when fusion with verb paradigm. CONCLUSIONS The way to reconstruct the AF is feasible with practical method and software. However its clinical value to determine the dominant hemisphere in Thai subject is needed to be more explore with more advance and promised technique. Keywords Arcuate fasciculus, lanquage pathway, diffusion tensor imaging

M. Recio1, L.C. Hernández2, J. Carrascoso1, R. Cano1, A. Alvarez1, V. Martïnez De Vega1 1

Hospital Universitario Quirón Madrid, Pozuelo de Alarcón, Spain; Departamento De Morfología Y Biología Celular, Facultad De Medicina. Universidad de Oviedo, Oviedo, Spain

2

PURPOSE We review the normal anatomy of the white matter (WM) tracts as they appear on directional diffusion tensor imaging (DTI) color maps and tractography. Anatomic gross dissection photographs are correlated with tractography to review the anatomy of those tracts, which are readily seen in most cases. We describe the principles of diffusion contrast and anisotropy, as well as their main clinical applications in developmental abnormalities, demyelinating disease, ischemic disease, infectious diseases, neurodegenerative disordes, neoplasms and preoperative studies. METHODS DTI MR images were obtained with a 3 T system and b values of 0 and 1000 s/mm2 were used. Our imaging protocol consisted of 82 diffusion encoding gradient directions when comparing with anatomic sections from cadavers and 25 diffusion encoding gradient directions when clinical applications were under evaluation. RESULTS WM fiber tracts traditionally have been classified as follows: Association fibers , projection fibers and commissural fibers. From a functional standpoint the most important fasciculus are: Pyramidal tract (motor studies); medial lemniscus and superior corona radiata (sensory studies); Meyer´s loop and optical radiations (visual studies)and arcuate and inferior frontooccipital fasciculi (language assessment). Myelination process, developmental brain disorders, demyelinating disease, hypoxic ischemic disease, infectious diseases, degenerative disease, tumors, preoperative mapping of vascular disease, epilepsy and psychiatric disorders are the most important clinical applications. CONCLUSION Diffusion tensor imaging and tractography are a key tool in the anatomical study of white matter fibers and projection, association and commissural fibers that improves conventional magnetic resonance imaging. Diffusion tensor imaging is able to show abnormalities in a wide variety of diseases such as developmental disorders or psychiatric disorders and is specially useful in the assessment of ischemic disease, multiple sclerosis and tumors. The use of tensor imaging in conjunction with functional studies (motor, visual, speech or memory), cortical mapping and intraoperative stimulation is a promising trend that helps prevent surgical neural damage. Keywords Diffusion tensor imaging, tractography, MRI P.1.122 THE ARCUATE FASCICULUS: ANALYSIS OF WHITE MATTER CONNECTION IN THAI LANGUAGE SYSTEM USING DIFFUSION TENSOR IMAGING C. Ngamsombat 1 , J. Wongsripuemtet 1 , S. Manochiopinig 2 , S. Piyaapittayanan1, S. Chaovongphanit3, O. Chawalparit1

P.1.123 PERCENT PERFUSION-TERRITORY AREA (%PT-A) CALCULATED BY TERRITORIAL ASL IMAGING: A UNIQUE PARAMETER TO INDICATE INTRACRANIAL HEMODYNAMICS M. Nagahata1, M. Obara2, Y. Minagawa3, S. Sato3, S. Nagahata1, R. Kondo4, S. Saito4, T. Kayama5 1 Yamagata City Hospital SAISEIKAN Stroke Center, Department of Diagnostic and Interventional Neuroradiology, Yamagata, Japan, 2 Philips Electronics Japan, Ltd., Tokyo, Japan, 3Yamagata City Hospital SAISEIKAN, Department of Radiology, Yamagata, Japan, 4Yamagata City Hospital SAISEIKAN Stroke Center, Department of Neurosurgery, Yamagata, Japan, 5Yamagata University Faculty of Medicine, Department of Neurosurgery, Yamagata, Japan

PURPOSE Territorial ASL (t-ASL) can color code each arterial perfusion territory as a color map. In this paper, we design a new parameter percent Perfusion-Territory Area (%PT-A) to indicate the area of each arterial perfusion territory numerically. We also investigate the usefulness of

Neuroradiology (2013) 55 (Suppl 1):S15–S159 this parameter by comparing post-surgical t-ASL with pre-surgical tASL in patients with cerebrovascular occlusive disease. METHODS We performed t-ASL imaging with Dual Labeling approach and LookLocker method on a 3.0 T Achieva scanner (Philips). After the acquisition, we calculated 7 slices, as “Accumulated map”, by accumulating all phases from phase 1 (post-label 550 ms) to phase 12 (postlabel 3300 ms). This accumulated map provides delay-insensitive territorial information. Then we calculated %PT-A of each arterial territory, such as right carotid arterial area, left carotid, and vertebrobasilar from all slice data. We compared the post-surgical %PT-A of each arterial territory with pre-surgical %PT-A in 11 patients with cerebrovascular occlusive disease (anterior circulation: 10, posterior circulation: 1) who underwent surgical reperfusion therapy (STA-MCA bypass: 4, CEA: 5, CAS: 1, balloon PTA: 1). RESULTS Post-surgical %PT-A of the affected artery was increased compared to pre-surgical %PT-A in 9 of 1 l cases, well-reflecting the change of intracranial hemodynamics revealed by cerebral angiography. In other 2 cases, no remarkable change in hemodynamics was observed between pre- and post-surgical cerebral angiograms. CONCLUSION %PT-A calculated by t-ASL is a unique and useful parameter to explain the area of intracranial perfusion territory of each artery objectively non-invasively. Keywords ASL, territorial ASL, cerebral artery occlusion P.1.124 CORRELATION BETWEEN ARTERIAL SPIN LABELING AND DYNAMIC SUSCEPTIBILITY CONTRAST PERFUSION MRI IN THE EVALUATION OF THE INTRACRANIAL LESIONS AT 3-TESLA MR O. Kitis1, A. Tosun2, C. Eraslan1, E. Ozgiray3, T. Yurtseven3, Y. Ertan4, M.C. Calli1 1

Ege University, School of Medicine, Radiology Dept, Izmir, Turkey, Izmir Bozyaka Education and Research Hospital, Radiology Dept, Izmir, Turkey, 3Ege University, School of Medicine, Neurosurgery Dept, Izmir, Turkey, 4Ege University, School of Medicine, Pathology Dept, Izmir, Turkey 2

PURPOSE To evaluate correlation between arterial spin labeling (ASL) and dynamic susceptibility contrast (DSC) perfusion MR imaging with regard to perfusion measurement (cerebral blood flow-CBF) of the intracranial lesions. METHODS 24 patients with intracranial tumor or tumor-like lesions were undergone MRI examination at 3-Tesla MRI system. In addition to conventional brain imaging, ASL and DSC perfusion MR imaging was performed. The cerebral blood flow values of the all intracranial lesions were collected and correlation between ASL and DSC perfusion MR imaging was assessed statistically. RESULTS Analyses demonstrated a positive linear correlation (r: 0.896) between ASL and DSC perfusion measurements (CBF) obtained from lesions by using region-of-interest analysis. CONCLUSION These results suggest that ASL and DSC methods provide same CBF measurements and ASL can be used as a non-invasive, inexpensive and reproducible perfusion MRI technique because of no contrast administration. Keywords Perfusion weighted MRI, brain neoplasms, magnetic resonance imaging

S123 P.1.125 HIPPOCAMPAL REVERSIBLE LESIONS IN A CASE OF TRANSIENT GLOBAL AMNESIA C. Gagliardo, F. Barone, F. Bencivinni, A. Banco, M. Midiri DI.BI.MEF, Radiology Section, University of Palermo, Palermo, Italy PURPOSE We present a case of transient global amnesia (TGA) onset in a 52-yearold male with a medical history of migraine. METHODS Patient was taken to ER by his colleagues which reported that after an emotional stress he suddenly appeared perplexed and started asking repetitive questions. In ER a neurological examination excluded other neurological signs or symptoms and it was confirmed that cognitive impairment was limited to the amnesia domain; electroencephalography was unremarkable and he had no history of epileptic seizures or head trauma. At the neurologic examination Capland and Hodges criteria were fulfilled and the diagnostic hypothesis of TGA was placed. He underwent to a brain CT (Siemens SOMATOM Definition AS+128) and later he underwent to a brain MRI (GE Signa HDxt 1,5 T). MRI protocol includes sagittal and axial T2w Fast Recovery Fast Spin Echo (FRFSE), axial and coronal T2w FLuid attenuated Inversion Recovery (FLAIR), axial T1w Fast Spin Echo (FSE), axial T2*w Gradient Echo (GE) and axial EchoPlanar Diffusion Weighted Imaging (EP-DWI, using a b value of 0 and 1000 s/mm2). RESULTS Brain CT and conventional MRI sequences did not show any relevant pathological findings but diffusion weighted imaging (DWI) showed two small areas of restricted diffusion in the right hippocampus. The amnesic syndrome resolved spontaneously within 24 h; in a brain MRI follow-up performed two week later those findings were no more appreciable. CONCLUSION DWI is very sensitive identifying the typical TGA lesions especially when a high b value (b>1000 s/mm2) is used combined to a thin section thickness (<5 mm). Even if the diagnosis of TGA is primarily clinical, MRI can give a positive diagnostic support. The etiology and pathogenesis of this rare neurologic syndrome is still unclear: several factors, such as migraine-related mechanism, focal ischemia, venous flow abnormalities, and epileptic-like phenomena, have been suggested and/or hypothesized. Further studies are needed but it’s plausible that more advanced imaging techniques and will help to better understand the underlying mechanisms. Keywords Transient global amnesia, diffusion weighted MRI, reversible lesions P.1.126 QUANTITATIVE T2*-MAPPING IN PARKINSON´S DISEASE USING AN AUTOMATED INVESTIGATOR INDEPENDENT “REGION-OF-INTEREST”-BASED APPROACH K. Egger1, M. Obmann1, R. Schwarzwald1, H. Mast1, L. Köstering2, C. Kaller2, S. Klöppel2, F. Amtage3, I. Mader1 1

Dept. of Neuroradiology, University Medical Center, Freiburg, Germany, 2Freiburg Brain Imaging Center, Freiburg, Germany, 3Dept. of Neurology, University Medical Center, Freiburg, Germany PURPOSE Early classification of Parkinson syndromes is difficult. One reliable biomarker in distinguishing these pathological entities is the brain iron accumulation due to degenerative process following intracellular αsynuclein aggregation.

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A new quantitative Magnetic Resonance Imaging (qMRI) technique provides an evaluation of differences in the distribution of the resulting iron accumulations. Previous ROI-based studies used hand-drawn ROIs, which is very time consuming and therefore hard to implement in clinical routine. The aim of this study was to determine significant differences of quantitative T2*-values in the substantia nigra (SN) of PD patients in comparison to healthy controls using a fully automated regionof-interest (ROI) based analysis approach in individual (native) space. METHODS 26 patients with idiopathic Parkinson´s disease and 26 age- and gender-matched healthy controls were scanned on the same 3 TMR-scanner. Apart from the standard protocol including a T1wMPR sequence, the MR measurements comprised additional T2*w-multiecho-acquisition using a single-shot echo-planar imaging sequence with 5 different echo times (TE) of 6.82, 12.04, 18, 25 and 33 ms and a voxel size of 0.6 x 0.6 x 4 mm. Creation of T2*-maps was performed using an in-house-software. ROIs (bilateral SN) were obtained with WFU PickAtlas software. Spatial preprocessing of T1w-images and ROI transformation to native space was performed using SPM8. The resulting mean decay constants were analyzed in SPSS using independent-samples T Test. RESULTS We found significant T2*-value differences (p<0.05) in the SN in PDpatients when compared to age- and gender matched healthy controls. CONCLUSIONS Quantitative MRI analyses may reflect the future of imaging based diagnosis in neurodegenerative diseases. Therefore fully automated methods of analysis are needed. This study report on significant differences in quantitative T2*-values in the SN of PD patients when compared to healthy controls using a fully automated investigator independent ROI based approach. Keywords T2*-mapping, Parkinson, substantia nigra

used to segment the WM. The T1 images were registered with the DTI. The data are divided into two sets: frontal lobe data and data on the brain as a whole. Two measurements, the fractional anisotropy (FA) and the mean diffusivity (MD), were derived from the WM in the DTI. Both linear regression modeling and cluster analysis were used to examine the associations between the DTI parameters. RESULTS The age vs. FA diagram showed that as age increases, FA decreases. Linear regression analysis confirmed a significant negative correlation between mean global FA and mean global MD (R2=0.6132, p<0.001, FA=0.7875–0.4043×age). The age vs. MD diagram showed that as age increases, so does MD. Consistent with this finding, linear regression analysis revealed a significant positive correlation between mean global MD value and age (R2=0.5309, p<0.001, MD=0.6279–0.0023×age). Mean global FA showed a significant negative correlation with mean global MD, indicating that there is age-related decreasing of water restriction within cerebral WM. In the cluster analysis, the mean frontal FA was significantly lower than the mean global FA. However, the difference between the mean frontal MD and the mean global MD was insignificant. CONCLUSIONS The experimental results showed that with increasing age, FA decreases, while MD increases. Those results corresponded to the natural degeneration of nerve fibers in normal-aged people. After dividing the data into frontal lobe versus whole brain, the analysis showed that the mean frontal FA was significantly lower than the mean global FA and the effect of white matter degeneration was significantly different from frontal lobe than whole brain. Keywords Fractional anisotropy, mean diffusivity, diffusion tensor imaging

P.1.127 QUANTIFYING THE CHANGES OF WHITE MATTER OF NORMAL ELDERLY IN DIFFUSION TENSOR IMAGING

S. Bermudez1, D. Matallana1, 2, P. Reyes2, J. Castro3, A.J. Morillo1, C. Filizzola2, G. Santiago1, B. Bernal4

C. Chen1, J.C. Fu2, S.H. Tsai1, J.W. Chai1, C. Troy3, S.K. Lee1 1 Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan, 2National Yunlin University of Science and Technology, Yunlin, Taiwan, 3Dayeh University, Changhua, Taiwan

PURPOSE The purpose of this study is to investigate age-related changes in White Matter (WM) within the elderly population. Diffusion Tensor Imaging (DTI) provided in vivo characterization of WM. Linear regression modeling and cluster analysis were applied to investigate the decline in cerebral (WM) integrity among the normal elderly. METHODS A Siemens 1.5 T MR scanner was employed to gather MR images. The 35 subjects met the following selection criteria: 1) age greater than 55; 2) score of 0 on the clinical dementia rating (CDR) scale; and 3) minimental status examination (MMSE) of at least 28. In each MPRANGE T1-weighted image, statistical parametric mapping (SPM) software was

P.1.128 UNDERSTANDING SOCIAL COGNITION ABILITIES IN TRAUMATIC BRAIN INJURY SUBJECTS: A PILOT STUDY OF FUNCTIONAL MRI fMRI IN TRAUMA BRAIN INJURY (TBI) COLOMBIAN PATIENTS

1

Fundacion Santa Fe de Bogotá University Hospital, Bogotá, Colombia, Xaveriana University Psyquiatric Department, Bogotá, Colombia, 3Los Andes University Biomedical Engineering, Bogotá, Colombia, 4fMRI Consulting Miami Children Hospital, Miami, FL, USA

2

INTRODUCTION How people understand actions has been centered in two hypotheses: The mirror-system hypothesis where the understanding of others is achieved via action simulation, and the social-network hypothesis which proposes that such understanding is achieved via the integration of critical biological properties (e.g., faces, affects) (Martin et al., 2007). OBJECTIVES

1. To create a fMRI paradigm to identify social cognition abilities in patients with TBI.

2. To identify differences between normal subjects and TBI patients regarding fMRI activations associated with Social cognition impairments when regular MRI images do not reveal a structural lesion.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 METHODS In this study, we assessed the areas of the brain that were engaged when 12 TBI patients and 12 Normal Control (NC) individuals observed moving dots with no meaning (Motion with no meaning MnM), a human dot figure performing an action of walking or seating (Biologic motion BM) and a human dot figure engaged in a social situation (Social Motion SM) such as two human dot figures sharing a soda or engaged on a violent action. RESULTS NC subjets activated Left Temporal Superior areas when observing BM and SM conditions. Nonetheless, TBI patients, within group analysis, did not show significant differences between paradigms: BM and SM. DISCUSSION The creation of the present paradigm concerns a simple observation task that can be useful in the understanding of Social network of patients with TBI that have severe social withdrawal, among other cognitive compromises, without major structural brain damage. Since TBI patients did not show differences in the brain-engaged areas during human and social paradigms, such tasks could become an useful clinical tool. Though further follow-up is required to track the association of social skills and brain activation, results can relate the patients´ everyday social functioning, the cognitive social assessment and the brain activity. Keywords Functional MRI, brain trauna, social cognition P.1.129 FUNCTIONAL MAGNETIC RESONANCE IN MEDICINE STUDENTS WITH AND WITHOUT PARTIAL SLEEP RESTRICTION S. Bermudez1, J.T. Hernandez2, I. Perez3, A.J. Morillo1, B. Bernal4, G. Santiago1, S. Torres2, A. Ocampo1, M. Ibañez2, S. Rascovsky5, A. Sanz5, P. Reyes1 1

Fundación Santa Fe de Bogotá University Hospital, Bogotá, Colombia, Los Andes University Imagine Group, Bogotá, Colombia, 3El Rosario University NeURos Group, Bogotá, Colombia, 4fMRI Consulting Miami Children Hospital, Miami, FL, USA, 5IATM Instituto de Alta Tecnología Médica de Antioquia, Medellín, Colombia

2

OBJECTIVE To describe the effects of partial sleep restriction (PSR) in the brain regions involved in cognitive inhibition processes, motor function and phonological fluency using functional Magnetic Resonance Imaging (fMRI). METHOD A sample of 12 graduate medicine students were subject to a follow-up of the number of hours of habitual sleep and underwent fMRI studies evaluating 4 paradigms before and after the PSR : Stroop (in standard and modified versions), right hand movement and verbal fluency. The PSR was equivalent to one night-shift, with at least 45 % sleep restriction with respect to the habitual sleep pattern during the previous week. The d2 attention test was done before and after the PSR to evaluate attention. RESULTS The d2 attention test did not show any significant differences between the habitual sleep condition and the PSR. Significant differences were found

S125 in BOLD activity for the motor function (P<0.05). Changes in BOLD activity were not observed for the Stroop nor verbal fluency paradigms. Keywords fMRI, sleep, motor abilities P.1.130 H-MR-SPECTROSCOPY OF INFERIOR COLLICULUS AS A TOOL FOR EARLY DIAGNOSIS OF ALZHEIMER DISEASE IN A FEASIBILTY STUDY Y. Aghazadeh1, B. Kress1, V. Paulose2, A. Sagheer3, F. Shad Kaneez3, A. Quirbach5, N. Hj Azaman4 1

Hospital Nordwest Frankfurt, Frankfurt, Germany, 2Jerudong Park Medical Center, Brunei, 3Institute of Health Sciences-University Brunei Darussalam, Brunei, 4RIPAS Hospital, Brunei, 5Dr. Horst-SchmidtKliniken, Wiesbaden, Germany PURPOSE Multiple neuropathological studies could show the affect of some structures in brainstem during the early stages in the development of Alzheimer disease (AD), many years before the first cognitive deficits become manifest. According to the neuropathological studies, inferior colliculus is one of those structures, which is being affected in the majority of AD patients. The typical neuropathological changes in AD damage neuronal structures in the way that many of Neurons loose their integrity and function, which leads to neuronal degeneration. The marker for neuronal activity and integrity in MRS is NAA. The decreaement of NAA in relation to the most stable metabolite Creatin (NAA/Cr-Ratio) can therefore show the neuronal damage in MRS. In case of inferior colliculus this decreasment can prove and demonstrate the affect of this structure in AD patients or in patients with MCI who are in risk to develope AD. In this way the NAA/Cr-Ratio can be a usefull diagnostic tool for the early diagnosis of AD or for followup measurements of MCI patients. METHODS Because of the difficulties in spectroscopy of inferior colliculus due to its anatomical position which is sorrounded by cerebrospinal fluid (CSF), it is mandatory to aprove the spectrums reproducibility of this structure in two seperated measurements with the aim to achieve the minimal percentage of variation. For this reason we have done a feasibility study with 14 healthy volunteers, in which SVS (with two different voxel sizes) and MVS were implemented. All these sequences were repeated after few days and the variation of NAA/Cr-Ratio between the first and second measurement were analysed. RESULTS The lowest variation of NAA/Cr-Ratio between the first and second measurement could be achieved for the SVS with the voxel size 15x12x18mm (FHxAPxRL) with the mean variation of 7.41 %. The mean variations for other MRS-sequences were above 18 %. CONCLUSION These results show the high reproducibility and stability of SVS with the aforementioned voxel size for the inferior colliculus in spite of its difficult anatomical position. In conclusion we will use this voxel size and relating adjustments in the following study to analyse the NAA/Cr-Ratio between healthy volunteers and patients with AD. Keywords MR-Spectroscopy, Alzheimer disease, inferior colliculus

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Traumatic brain injury P. M. Parizel & F. De Belder & C. Venstermans & J. van Goethem & L. van den Hauwe & Ö. Özsarlak & T. Van der Zijden & M. Voormolen & A. Maas &

Modern neuroradiological techniques play an essential role in the diagnostic work-up of patients with traumatic brain injury (TBI). Imaging findings increasingly determine patient management and greatly influence the clinical course. Moreover, advanced imaging techniques can serve as (surrogate) biomarkers to predict outcome and prognosis. In the acute setting, the main goal of imaging in head-injured patients is to detect “primary injuries”, which occur as a direct result of the impact with immediate damage to brain tissue. Examples include fractures, different types of traumatic hemorrhage (epidural, subdural, intracerebral, subarachnoid), cerebral contusions, diffuse axonal injury (DAI). In acute TBI patients, CT remains the first choice technique to determine the presence and extent of traumatic brain injuries, and to guide surgical planning if appropriate. Multi-detector CT allows simultaneous assessment of head and cervical spine, obviating the need for plain X-rays. In many major trauma centers, assessment of traumatic blood vessel injury has become part of the initial diagnostic evaluation, and can be performed with CT-angiography (or MR-angiography). In the subacute period, after stabilization and management of the patient, the focus usually shifts towards the evaluation of “secondary injuries”, which are caused by systemic factors such as increased intracranial pressure, edema, brain herniation, decreased cerebral blood flow, excitotoxic damage, etc. While CT can be used in the follow-up of cerebral herniation with shift of the midline structures or transtentorial displacement of brain tissue, the best technique to document these lesions is multiparametric MRI including diffusion, perfusion, and susceptibilityweighted imaging. Whenever there is a discrepancy between the clinical neurological status of a TBI patient and the CT findings, MRI is indicated. For example, diffuse axonal injury often remains a controversial diagnosis because the brain may appear quite normal on conventional CT examinations, which grossly underestimate the extent of cerebral damage; in these cases, MRI with diffusion weighted imaging, ADC mapping and diffusion tensor imaging is very useful to reveal the true extent of the lesions. Diffusion abnormalities have been shown to correlate with outcome. The development of recent advances in neuroimaging techniques, such as diffusion tensor imaging (DTI) with fractional anisotropy (FA) or mean diffusivity (MD) mapping, allows better characterization of microstructural brain abnormalities, even when traditional MRI sequences appear normal (e.g. in patients with mild TBI). These techniques have

P.M. Parizel : F. De Belder : C. Venstermans : J. van Goethem : L. van den Hauwe : Ö. Özsarlak : T. Van der Zijden : M. Voormolen : A. Maas Departments of Radiology and Neurosurgery, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium email: [email protected]

allowed neuroimaging studies to progress from a qualitative to a quantitative assessment. There is increasing scientific evidence that quantitative imaging techniques can serve as biomarkers of cerebral injury. These methods provide valuable information regarding the staging of lesions, the (ir)reversibility of white matter changes, and offer the potential to monitor changes in brain damage over time. From a medicolegal point of view, multiparametric imaging techniques are becoming very important in identifying sequelae, determining prognosis, and guiding rehabilitation of TBI patients. In conclusion, new multiparametric imaging techniques in neuroradiology improve our understanding of the pathophysiology of craniocerebral trauma. These methods allow the detection of elusive abnormalities, even when routine imaging studies appear normal (for example in patients with mild head trauma). Neuroradiologists should be encouraged to adopt quantitative imaging techniques in the routine diagnostic work-up of TBI patients, in order to obtain a complete inventory of the traumatic cerebral lesions. Development of a standardized pattern analysis approach, and structured reporting of findings will become important tools to facilitate communication with clinicians. The widespread application of advanced multiparametric imaging techniques in TBI patients should enable us to elucidate the biological substrate of posttraumatic cognitive and behavioral changes (such as the ‘postconcussion syndrome’). In summary, new techniques help us detect subtle brain damage, and lesions that have previously gone undiscovered because of lack of sensitivity of earlier neuroimaging techniques. Suggested reading 1.

2. 3. 4.

5.

Bendlin BB, Ries ML, Lazar M, Alexander AL, Dempsey RJ, Rowley HA, Sherman JE, Johnson SC. Longitudinal changes in patients with traumatic brain injury assessed with diffusion-tensor and volumetric imaging. Neuroimage. 2008; 42(2): 503–514 Maas AI, Menon DK. Traumatic brain injury: rethinking ideas and approaches. Lancet Neurol. 2012; 11(1): 12–13. Parizel PM, Van Goethem JW, Ozsarlak O, Maes M, Phillips CD. New developments in the neuroradiological diagnosis of craniocerebral trauma. Eur Radiol. 2005; 15(3): 569–581. Sidaros A, Engberg AW, Sidaros K, Liptrot MG, Herning M, Petersen P, Paulson OB, Jernigan TL, Rostrup E. Diffusion tensor imaging during recovery from severe traumatic brain injury and relation to clinical outcome: a longitudinal study. Brain. 2008; 131(Pt 2): 559–72 Yuh EL, Mukherjee P, Lingsma HF, Yue JK, Ferguson AR, Gordon WA, Valadka AB, Schnyer DM, Okonkwo DO, Maas AI, Manley GT; TRACK-TBI Investigators. Magnetic resonance imaging improves 3month outcome prediction in mild traumatic brain injury. Ann Neurol. 2013; 73(2): 224–235.

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MRI in traumatic spinal injury J. W. M. van Goethem & C. Venstermans & F. De Belder & L. van den Hauwe & P. M. Parizel &

MRI has gained importance in imaging of spinal trauma with its increased availability for the emergency room physician. It is apparent that the depiction of the spinal cord is of primary importance, and with the adoption of MR, the utility of myelography and post-myelography CT has diminished to the point of vanishing (in the absence of contraindications to MR). MR is capable of depicting the vertebra and supporting structures, intervertebral disks, the spinal cord and nerve roots, and traumaassociated injuries such as hemorrhage, traumatic disk herniations, and primary cord injury such as hematomas, edema, and even cord transection. Any patient with presumed spinal cord injury should undergo an emergent MR study. MR is superior at depicting the previously mentioned lesions which guide surgical management in these patients. Careful clinical examination with a determined level of injury is an excellent means of directing the level to be studied. Many trauma protocols may also mandate evaluation of the other spinal segments to exclude additional injury which may be masked by a higher level spinal cord injury. The sensitivity of MR

J. W. M. van Goethem : C. Venstermans : F. De Belder : L. van den Hauwe : P. M. Parizel University Hospital Antwerp, Antwerp, Belgium email: [email protected]

for injuries of the soft tissue associated with trauma is well known, but MR may also demonstrate changes within the bone marrow of traumatized vertebrae which are inapparent on plain film studies, and even on CT, such as bone contusions. MR has also been shown to be both sensitive and specific for ligamentous injury in the trauma setting. We have used MR to provide a “ligament screen” exam for major trauma patients for several years now, with consistent results. The typical exam protocol for this purpose includes sagittal T1, sagittal T2, and sagittal STIR images, as well as axial imaging. Edema in the interspinous or supraspinous ligaments is particularly conspicuous on STIR images. Some observers may prefer fatsuppressed T2 images, which provide similar conspicuity of the changes of ligamentous injury. In whiplash patients special attention to the ligaments of the craniocervical junction is important. In these patients a dedicated 3D proton density sequence with thin reconstructed slices is able to show lesions to the transverse, alar and atlanto-occipital ligaments as well as the tectorial membrane.

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Requests from neurooncologist J. Steinbach

The clinical neurooncologist relies on the neuroradiology expert to answer a number of questions that are paramount for patient care. Recently, these have extended from basic information regarding morphology, location and diagnosis to biological and molecular features. In addition, there is high pressure to establish prognostic and predictive imaging markers. Finally, the assessment of tumor status, i.e. progression versus response, is rapidly increasing in complexity in the age of antiangiogenic therapy, local therapies and immunotherapy. All these issues pose significant challenges for the neuroradiologist and demand special expertise and experience in brain tumor imaging as well as advances technical equipment. Some of the most pertinent issues with a focus on gliomas are listed below. DIAGNOSIS: For incident lesions, the clinical neurooncologist needs information beyond MR-morphology and location that provide information on the type of process. For glial tumors, grading is very important. The presence of key genetic alterations may soon also be an issue for the neuroradiologist. Information about tissue oxygenation, pH and metabolite levels may also soon become important. For the planning of stereotactic biopsies, the identification of „hotspots“ by, e.g., MR-perfusion and MR-spectroscopy represents a considerable advance.

J. Steinbach Dr. Senckenberg Institute of Neurooncology, Frankfurt, Germany email: [email protected]

SURGICAL TREATMENT: For the planning of resections, the delineation of eloquent areas by functional imaging such as fMRI and DTI is essential in some cases. An integration of data derived from these techniques with TMS and intraoperative testing will be important in the future. NONSURGICAL TREATMENT: Prognostic and predictive imaging markers will in the future complement molecular markers and aid in establishing rational and individualized therapies. A current area of particular interest is the role of early response imaging markers during treatment of glioblastoma with bevacizumab. ASSESSMENT OF TUMOR STATUS: Finally, the assessment of tumor status, i.e. progression versus response, is becoming more challenging. With radiochemotherapy, pseudoprogression, i.e., early inflammatory responses mimicking true tumor progression, needs to be recognized. Successful immunotherapies may also result in progressive changes that are difficult to differentiate from tumor progression. Conversely, antiangiogenic therapies may, by reducing vascular permeability and thus contrast medium uptake, mask vital tumor („pseudoresponses“). Some of these issues are adressed in the RANO-criteria, that are now the new standard for the response assessment in neurooncology.

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Susceptibility weighted techniques R. Gasparotti & R. Liserre

INTRODUCTION SWI (Susceptibility-Weighted Imaging) is a relatively new Magnetic Resonance (MR) technique that provides innovative sources of contrast visualizing the changes in magnetic susceptibility that are caused by different substances like iron, hemorrhage, calcium. The basic concept of this technique is the idea to maintain phase information into the final image, discarding phase artifacts and keeping just the local phase of interest. Prior to the clinical implementation of SWI, susceptibility imaging has relied only on GE sequences. SWI differs significantly from a T2*weighted GE sequence: it is based on a long-TE high-resolution flowcompensated 3D GE imaging technique with filtered phase information in each voxel. The combination of magnitude and phase data produces an enhanced contrast magnitude image which is particularly sensitive to haemorrhage, calcium, iron storage and slow venous blood, thus allowing a significant improvement compared to T2* GE sequences. After imaging acquisition, incidental phase variations due to static magnetic field inhomogeneities are removed. The phase mask is then multiplied with the magnitude data to enhance the visualization of vessels or foci with susceptibility effects (1). SWI is therefore especially helpful in the detection of calcifications and microhemorrhages which are both characterized by low signal. The evaluation of the corrected phase images allows the differentiation between the two substances, since calcifications appear bright because of positive phase shift and hemorrhages appear dark because of negative phase shift. A supplementary source of information in SWI is primarily associated with the magnetic susceptibility differences between oxygenated and deoxygenated hemoglobin. The paramagnetic properties of deoxyhemoglobin (BOLD-effect) and the prolonged T2* of venous blood were used as an intrinsic contrast agent leading to a phase difference between vessels containing deoxygenated blood and surrounding brain tissue, resulting in signal intensity cancellation. Thus, deoxy-Hb can behave like a contrast agent with long TEs for differentiating arteries from small veins, which can be as small as 100–200 μm and therefore difficult to detect with conventional magnetic resonance MR Angiography techniques, such as time-of-flight (TOF) or phase contrast (PC). For this reason, the phase added information which are usually not available in the conventional magnitude image make SWI well suited for the visualization of very small vessels such as R. Gasparotti : R. Liserre Neuroradiology Unit, Dept. Diagnostic Imaging, Spedali Civili, University of Brescia, Brescia, Italy email: [email protected]

teleangiectasies or tumor neoformed vessels as a result of a combination of slow flow with changes of deoxyhemoglobin concentration. Latest advances have allowed the technique to be refined, thereby expanding its clinical applicability to brain imaging as a complementary source of information to conventional T1 and T2-weighted imaging sequences.

TECHNICAL ASPECTS At our institution, MR imaging is performed by using two 1.5 T scanners (Magnetom Avanto and Aera; Siemens, Erlangen, Germany) with 12 and 32-channel head coils respectively. SWI is obtained with a long-TE, fully flow-compensated 3D gradient echo sequence with the following parameters: TR/TE, 49/40 ms; Flip Angle, 15°; rectangular FOV, 7/8; matrix size, 280x320; slice thickness, 1.6 mm (80 slices in a single slab matrix size); iPAT factor, 2; acquisition time, 5 minutes. Images are acquired in the axial plane parallel to the bicommissural line. The SWI sequences are reconstructed with the minimum intensity projection algorithm (minIP) and multiplanar reformation (MPR) techniques to obtain images with thickness (3–10 mm) and position comparable to those of conventional sequences. The minIP algorithm has the characteristic to enhance the visualization of veins while attenuating the signal from the brain tissue. SWI sequences have some intrinsic disadvantages, which are mainly represented by artifacts caused by undesirable sources of magnetic susceptibility which occur at air-tissue interfaces, therefore limiting the investigation of areas next to paranasal sinuses and temporal bone. The “blooming artifact”, useful in the majority of cases, could also be not needed in some situations, producing normal tissue signal cancellation and loss of anatomical borders. The sequence acquisition time on a 1,5 T scanner ranges from 5 to 8 minutes, depending on the spatial resolution and the needed coverage of the brain, leading to an increased incidence of movement artifacts. Imaging at high field strength have some advantages over 1.5 T in delineation of even smaller vessels belonging to the venous network with shorter scan times, due to higher signal to noise ratio, higher spatial resolution and increased susceptibility effects. However susceptibilitybased signal loss and severe image distortion caused by air–tissue interfaces or other sources of local field inhomogeneity are much more severe at higher fields, thus reducing the SWI usefulness in the evaluation of the posterior fossa and skull base. SWI has been investigated also at 3 T and 7 T with excellent results especially concerning brain tumors and detection of cerebral microbleeds (2).

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CLINICAL APPLICATIONS: INTRACRANIAL TUMORS Brain MR Imaging predictors of tumor grade include contrast enhancement, edema, mass effect, cyst formation or necrosis, hemorrhage, metabolic activity and cerebral blood volume. SWI can provide a thorough assessment of the internal angioarchitecture of brain tumors (increased microvascularity inside and beyond the tumor margins), together with the identification of foci of hemorrhage and calcification, thus representing an additional tool in the neuroradiological grading of cerebral neoplasms (Figs. 1–2). The administration of a contrast agent (CE-SWI) allows the discrimination between those three entities, as only blood vessels will change their signal intensity, while calcifications and regions of inactive hemorrhage (which can be differentiated each other by the evaluation of phase images, as described above) will not. The utility of CE-SWI has been found equivalent or even superior to CE-T1 images in the evaluation of most tumors with necrotic areas: the particular contrast combination within SWI images permits the simultaneous visualization of the information otherwise obtained by a multimodal imaging approach including CT scans, CE-T1 SE, FLAIR and T2*conventional GE sequences. As regards tumor grading, a positive abnormal enhancement around the tumor rim on post-contrast SWI, indicating breakdown of the blood–brain barrier, seems to be more specific for high-grade tumors. It has been observed that GBMs have a higher grade of susceptibility signals than lymphomas, but according to our and other experiences, intratumoral microbleeds are not exclusive of high grade glial tumors. Hori et Al. confirmed the efficacy of SWI also at 3 T in structural characteristics analysis of gliomas, but sustained the necessity of a standardized method for image analysis in clinical routine (3). It is well known that the growth of solid tumors, such as gliomas, is dependent on the angiogenesis of pathologic vessels. The clinical potentials of contrast-enhanced BOLD MR Venography at 3 T and 1.5 T for the study of brain tumors were first reported by Barth et Al., who demonstrated variable venous patterns in various types of tumors and in different parts of the lesions (edema, contrast enhancing area, necrosis), which might represent increased blood supply and particular vascular patterns around fast growing malignant tumors (4). Pinker et Al. found a correlation between intratumoral susceptibility effects at 3 T, PET results and hystopathologic grading (2). A correlation with MR perfusion-weighted imaging (PWI) has also been attempted, but in our opinion larger comparative studies of PWI and SWI are still needed to determine a more precise role of these techniques in grading of cerebral neoplasms. As regards follow-up studies, SWI has been recently proposed as predictor of clinical response of Glioblastoma to a combination of anti-angiogenic, cytotoxic, and radiation therapy (5). A preliminary study suggested also a possible use of CE-SWI in the ADCguided differential diagnosis between recurrent primary brain tumor and radiation injury, by excluding regions that may correlate to vascular compartments containing blood products and areas of necrosis (6).

Figure 1. Characterisation and grading of a glial tumor. A. SWI, minIP: presence of intratumoral susceptibility signals due to microhaemorrhages in right parahippocampal gyrus (arrow). B. Postcontrast T1-weighted image showing BBB breakdown (arrow). C. Relative cerebral blood volume (rCBV) map obtained with DSC-PWI technique demonstrates moderate hypervolaemia in the same area (arrow). The neuroradiological hypothesis of a high-grade glioma was confirmed at targeted biopsy.

itself and of imaging analysis methods and therefore further investigation seems to be needed for its extensive clinical application in this field.

Figure 2. Characterisation of a hemorrhagic lesion. CONCLUSION SWI, a combination of gradient-echo sequences with phase information, is an imaging technique that provides more information in addition to conventional sequences and is useful, mainly with contrast enhancement, also for evaluating characteristics and architecture of brain tumors in vivo. Despite some inherent limitations, SWI has increasing indications in brain tumors diagnosis and follow-up. Disadvantages are mainly represented by the complex contrast of SWI

A. Pre-contrast T1W image of a hemorrhagic lesion of corpus callosum genu. B. SWI unprocessed image helps in the sharp definition of a dark ring-shaped left paramedian lesion inside the methemoglobin components (arrow) and in decision-making of DCE-PWI technique use for perfusion assessment. C. Post-contrast T1W image and D. DCE colorcoded map corroborate the hypothesis of a hemorrhagic metastasis. Targeted stereotactic biopsy in the supposed neoplastic area confirmed a metastasis from a primary hepatocellular carcinoma.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Reference List 1. 2.

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Haacke EM, Mittal S, Wu Z, Neelavalli J, Cheng YC. Susceptibilityweighted imaging: technical aspects and clinical applications, part 1. AJNR Am J Neuroradiol 2009; 30:19–30. Pinker K, Noebauer-Huhmann IM, Stavrou I, et al. High-resolution contrast-enhanced, susceptibility-weighted MR imaging at 3 T in patients with brain tumors: correlation with positron-emission tomography and histopathologic findings. AJNR Am J Neuroradiol 2007; 28:1280–1286. Hori M, Mori H, Aoki S, Abe O, Masumoto T, Kunimatsu S, Ohtomo K, Kabasawa H, Shiraga N, Araki T. Three-dimensional susceptibilityweighted imaging at 3 T using various image analysis methods in the estimation of grading intracranial gliomas. Magn Reson Imaging. 2010 May;28(4):594–8.

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Barth M, Nobauer-Huhmann IM, Reichenbach JR, et al. Highresolution three-dimensional contrast-enhanced blood oxygenation level-dependent magnetic resonance venography of brain tumors at 3 Tesla: first clinical experience and comparison with 1.5 Tesla. Invest Radiol 2003; 38:409–414. Lupo JM, Essock-Burns E, Molinaro AM, Cha S, Chang SM, Butowski N, Nelson SJ. Using susceptibility-weighted imaging to determine response to combined anti-angiogenic, cytotoxic, and radiation therapy in patients with glioblastoma multiforme. Neuro Oncol. 2013 Apr;15(4):480–9 Al Sayyari, Buckley R, McHenery C, Pannek K, Coulthard A, Rose S. Distinguishing recurrent primary brain tumor from radiation injury: a preliminary study using a susceptibility-weighted MR imaging-guided apparent diffusion coefficient analysis strategy. AJNR Am J Neuroradiol 2010; 31:1049–1054.

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ADVANCED COURSES OF THE ESNR MEETING 2013

MR derived biomarkers for quantification of microvascular disease in the ageing brain and neurodegenerative disorders Alan Jackson

Vascular/ischaemic injury is one of the commonest forms of brain disease particularly in the ageing population. MR provides unique tools to demonstrate and quantify the presence of vascular brain disease and it’s sequelae and has become a de facto “gold standard” for clinical investigation. In some cases, the cause of an ischaemic lesion such as an infarct can be definitively identified by demonstration of a large vessel occlusion. However, in the majority of cases the aetiological factors giving rise to apparently ischaemic changes are unclear. Many studies have examined the number and distribution of whitematter lesions in ageing and age-related diseases. A number of quantitative and semiquantitative scoring systems exist which allow stratification of phenotypic groups for research purposes. These include the well-known and commonly clinically used Fazekas scale and the more complex Schelten’s scoring system which is most commonly used for research purposes. There is convincing pathological and imaging-based evidence that these white matter lesions represent the consequence of local ischaemic injury. The presence of multiple white-matter lesions (leukoariaosis, LA) is a common finding and clinical radiologists typically described extensive white-matter hyperintensities as “microvascular disease”. However, pathological studies show that small vessel disease is present in only 55 to 60 % of these cases. Therefore, although LA may provide evidence of an underlying vascular insult it provides no significant evidence as to the nature of that vascular insult or its pathogenesis. The realisation that white matter lesions could occur in the absence of microvascular disease has led to a large number of studies attempting to identify the pathogenetic mechanisms involved and to develop appropriate imaging biomarkers to describe them. True microvascular disease is recognised by the pathologist by the presence of increased tortuosity and irregularity in small arteries and arterioles (grade 1), sclerosis of vessel walls with hyalinosis and lipid deposits in the wall and loss of smooth muscle (grade 2) and eventual fibrotic wall thickening with onion skinning, loss of the muscularis and the elastic lamina and focal necrosis within the vessel wall (grade 3). Grade 2 and 3 disease are associated with dilatation of perivascular spaces (Virchow Robin spaces; VRS). Visualisation of dilated VRS was therefore identified as a potential imaging biomarker of microvascular disease. Dilated A. Jackson University of Manchester, Manchester, United Kingdom email: [email protected]

VRS can be seen on appropriate MR sequences, particularly very heavily T2 or T1 weighted high spatial resolution sequences. Comparisons of simple scoring systems describing the number and distribution of VRS with white matter lesion grading scores showed considerably greater diagnostic specificity in distinguishing late-onset, treatment resistant depression (known to be a symptom of microvascular disease) from responsive depression, vascular dementia from neurodegenerative dementias and can separate groups of individuals with high and low/risk factors. Alternative scoring systems are available and VRS dilatation has now become a standard biomarker in cerebral vascular studies. Small vessel disease may also be considered to change arteriolar flow rates and flow patterns. This led to the development of quantitative techniques to image small vessel arterial blood flow using dynamic contrast enhanced-MRI. The use of high spatial resolution, isotropic voxels, combined with software to extract linear transit time vectors from the dataset allows the mapping of regional small vessel blood flow rate. However this rather demanding technique has not found widespread clinical Or research use. Another specific feature of microvascular disease is structural change in the vessel wall with consequent reductions in elasticity and compliance. In theory this should lead to increased transit of the systolic pulse wave from a large basal arteries into the brain causing capillary pulsatility and consequent increase in cerebral aqueduct CSF flow. Using phase contrast angiography techniques to measure flow patterns in the major vessels and cerebral aqueduct allows modelling of flow patterns which can produce absolute estimates of small vessel compliance. More pragmatically, The speed with which the arterial systolic pulse wave propagates to the aqueduct correlates closely with vascular compliance. This, simply measured metric has also been shown to hold diagnostic specificity for the presence microvascular disease in late-onset depression, dementia and in normal is with high vascular risk profiles. Other mechanisms of vascular injury have also increasingly attracted interest. Studies of micro-embolic disease, mainly using transcranial Doppler have demonstrated correspondence between white-matter lesions, disease aetiology vascular and embolic numbers in normal ageing and vascular and neurodegenerative dementias. Another topical mechanism of vascular injury is failure of cerebral blood flow autoregulation. Until recently the auto regulatory system could be studied only by using transcranial Doppler to measure middle cerebral artery flow velocities. Based on this technique there is an extensive literature demonstrating cerebral

Neuroradiology (2013) 55 (Suppl 1):S15–S159 vascular autoregulation in the face of hypotension and normotensive hypovolaemia. More recently, we have developed an MR compatible lower body negative pressure (LBNP) system, which allows subjects to be exposed to normotensive hypovolaemia and hypertensive hypovolaemia in a graded fashion. The stimulus can be maintained over a significant period of time allowing the use of imaging biomarker is derived from magnetic resonance imaging. This technique allows simple measurements of changes in cerebral blood flow using phase contrast angiography and, much more detailed anatomical studies of blood flow changes using arterial spin labelling. We have demonstrated that, in normal subjects, normotensive hypovolaemia does not initiate classical cerebral autoregulation but results in decreases in blood flow that closely parallel the measured decrease in cardiac output. Within the brain, ASL demonstrates maintenance of grey matter blood flow despite an overall reduction in CBF of up to 25 %. The use of ASL allows us to study bolus arrival time which appears to provide an excellent surrogate indicator of vascular dilatation. And thus it appears that in the presence of normotensive

S133 hypovolaemia grey matter blood flow is maintained in the presence of decreasing overall CBF presumably bifocal vasodilatation induced by neurovascular coupling. In conclusion, imaging biomarkers are providing increasingly specific indicators of the pathogenesis of diffuse cerebral vascular disease. These studies are already redefining our understanding of cerebral vascular autoregulation in health and these techniques are likely to become mainstays of research into cerebral vascular injury. I will present a review of work from the past 10 years attempting to provide MR biomarkers for specific mechanisms of ischaemic injury. I will review the work leading to the identification of dilated perivascular spaces and of changes in patterns of CSF pulsatility as specific biomarkers of atherosclerotic small vessel disease. I will also discuss potential approaches to measurement of failure of cerebral autoregulatory mechanisms using a novel technique combining phase contrast measurements of cerebral blood flow with lower body negative pressure plethysmography as a controllable and progressive autoregulatory stimulus.

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Diffusion techniques in brain tumors P. M. Parizel & F. De Belder & C. Venstermans & J. van Goethem & L. van den Hauwe & T. Van der Zijden & M. Voormolen & W. Van Hecke

DIFFUSION WEIGHTED IMAGING Diffusion-weighted imaging (DWI) is a technique that generates images, which reflect differences in diffusion characteristics within the brain, or other organs in the human body. DWI indicates differences in the Brownian motion of water molecules within a microstructural environment of a biological tissue. DWI can be performed by adding powerful dephasing and rephasing diffusion gradients to a standard (spin echo) MRI sequence, before and after the 180° pulse. These gradients have to be applied in (at least) 3 different directions. Differences in the signal of individual voxels are mapped onto twodimensional “trace” images, which are averaged from the individual diffusion weighted images (in linear algebra, the trace of a matrix is defined as the sum of the elements on the main diagonal). The signal intensity of a voxel in the trace image is inversely correlated with the rate of water diffusion in that location; areas with restricted diffusion appear bright (hyperintense) and areas with facilitated diffusion are dark (hypointense). While the signal intensity of a voxel in a trace image is mainly determined by the rate of diffusion, other elements also come into play (e.g. T2-relaxation and flow). In order to eliminate these additional components, parametric images can be calculated which reflect the apparent diffusion coefficient (ADC), thereby eliminating other factors such as T2-shine through phenomena. ADC images are parametric maps, which reflect the spatial distribution of water diffusion in the biological tissue under study. ADC values are expressed in mm2/sec. The greater the microstructural organization of a tissue is, the lower the ADC value. Low ADC values indicate ‘restricted’ diffusion, and high ADC values reflect ‘facilitated’ diffusion. The rate of diffusion of water molecules in the brain is determined by many factors, but mainly reflects the microscopic environment. This implies that ADC values can be used in the preoperative diagnosis of brain tumors to assess differences in tumor cellularity. Cell membranes and intracellular organelles impede the free diffusion of water molecules, thus yielding lower ADC values on diffusion weighted images. P. M. Parizel : F. De Belder : C. Venstermans : J. van Goethem : L. van den Hauwe : T. Van der Zijden : M. Voormolen : W. Van Hecke : Department of Radiology, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium email: [email protected]

Brain tumors with high cellularity, high nucleus/cytoplasm ratio and small extracellular spaces have lower ADC values (restricted diffusion). Examples include, among others, cerebral lymphoma and primitive neuroectodermal tumor. There is an inverse correlation between cell density and ADC values of brain tumors. In general terms, ADC values tend to decrease with increasing WHO tumor grade. Unfortunately, there is considerable overlap between ADC values among different types of tumors, and even within one tumor, so the ADC value cannot reliably be used as a predictor. ADC values have been successfully applied to differentiate necrotic brain tumors (e.g. glioblastomas, cystic metastases) from bacterial abscesses. These lesions often present comparable morphological features as an irregular, thick-walled rim-enhancing mass with a non-enhancing center and prominent perifocal edema. In a bacterial abscess, which contains pus, diffusion is restricted, which corresponds to markedly increased signal intensity on the trace images, and lowered ADC values. Conversely, in necrotic tumors, the center of the lesion remains dark on trace images, and ADC values are not decreased (no diffusion restriction). Recent literature data indicate that DTI with FA provides superior diagnostic performance when compared to DWI with ADC mapping. Similarly, ADC values have been used to make the differential diagnosis between epidermoids and arachnoid cysts. Both types of lesions present similar T1 and T2 signal intensities, and may be difficult to differentiate. On DWI, epidermoids, or ‘pearly tumors’ as they are sometimes referred to, typically present with markedly restricted diffusion: very bright on trace images, with lowered ADC values. The opposite is true for arachnoid cysts. Non-echoplar DWI has proven to be very useful in the evaluation of cholesteatomas. In post-operative patients with equivocal CT findings, DWI allows differentiation recurrent cholesteatoma of the middle ear from post-operative changes such as scar tissue, granulation tissue and inflammatory changes. In the postoperative evaluation of patients with brain tumors, DWI has been successfully applied to differentiate recurrent glioma from radiation necrosis. This can be done by comparing the ADC ratio of the contrast enhancing lesion versus the normal appearing brain in the heterolateral hemisphere. ADC ratios tend to be significantly higher in regions with radiation injury versus areas with recurrent tumor. The increased ADC values, which occur during chemotherapy, most likely reflect a reduction of tumor cellularity and widening of the extracellular spaces. When the tumor recurs, the ADC values decrease back to baseline values.

Neuroradiology (2013) 55 (Suppl 1):S15–S159 DWI with ADC mapping can play an important role in distinguishing tumor components; a surgical biopsy should be directed towards the area of the tumor with the highest cell density (lowest ADC value). There is some evidence that ADC values can play a role in judging the grade of astrocytomas. Moreover these techniques help to determine the tumor boundary of glial tumors. The underlying idea is that diffusion is more restricted in ‘contaminated edema’ (containing malignant cells) than in pure vasogenic edema (containing only increased amounts of intercellular water).

DIFFUSION TENSOR IMAGING Whereas DWI reflects the magnitude of water diffusion (ADC value), diffusion tensor imaging (DTI) also provides information about the direction along which the water diffusion occurs and the threedimensional shape of diffusion in space. In DTI, it is necessary to apply the diffusion gradients in numerous directions (the more the better, but at least 6). In this model, diffusion can be represented by a ‘tensor’, which provides a graphical three-dimensional representation of diffusion as an elongated ovoid. In mathematics, a tensor can be represented as a multi-dimensional array of numerical values which reflects correspondences between sets of geometric vectors, e.g. the different directions of diffusion in a biological tissue. In an isotropic medium (e.g. cerebrospinal fluid in the ventricles), diffusion is equal in all directions, and the tensor can be represented by a sphere; in an anisotropic medium (e.g. heavily myelinated white matter fibers in the corticospinal tracts), the tensor presents an elongated ellipsoid, because the diffusion is predominant along the direction parallel to the long axis of the axons, while limited in the direction perpendicular to the main axis of the fiber tracts. DTI information is represented graphically in parametric images, for example fractional anisotropy (FA) or mean diffusivity (MD). FA values range between 0 and 1; an FA value of 1 indicates perfectly isotropic diffusion, whereas an FA value of 0 indicates absolute anisotropic diffusion. Postprocessing programs alllow us to reconstruct white matter fiber tracts by connecting voxels that have a similar orientation and degree of diffusion. This process is known as fiber tracking, and can provide of graphical rendering of white matter tracts in the brain and spinal cord. In patients with brain tumors, DTI is important because the technique provides information about white matter anatomy and structural connectivity. DTI can be studied using either a deterministic or probabilistic tracking approach. A detailed description of these techniques is beyond the scope of this presentation. FA values have been linked to the degree of malignancy of brain tumors. For example, FA mapping has a certain value in differentiating highgrade from low-grade astrocytomas, with high grade tumors presenting with lower FA values. One of the main goals of DTI is to provide reliable information about the tumor and its surroundings, as well as the connections of the tumor

S135 to adjacent brain areas, in order to assess resectability. There is increasing evidence that DTI with FA measurements is more sensitive than ADC to outline the tumor boundary and may be more accurate in differentiating infiltrative tumor, vasogenic edema, and normal brain tissue than conventional MRI. DTI with fiber tracking can provide information about the anatomical relationship between a brain tumor and the adjacent white matter fiber tracts, as well as the position and integrity of subcortical fiber bundles. This knowledge may be vitally important in avoiding neurological deficit after operation. Witwer et al. classified involvement of white matter tracts into 4 types: displaced, edematous, infiltrated, and disrupted. Displacement implies that the white matter tracts retain a normal anatomic structure, but are shifted to an abnormal location or show an abnormal orientation. Infiltration is used when there is partial disintegration of the fiber bundles, relative to the corresponding tract in the contralateral hemisphere. Disruption occurs when the continuity of fiber tracts is interrupted. Edematous infiltration of fiber tracts is found in areas of peritumoral edema, where the increased amount of intercellular water separates and splays the white matter tracts. Many centers are now using DTI with fiber tracking in the presurgical planning for tumor excision. In only a few years, DTI has evolved into a robust and reproducible technique that accurately provides anatomical information about white matter tract location, orientation, and projections. This knowledge enables neurosurgeons to achieve maximum resection of the brain tumor, while avoiding postoperative loss of neurological function.

CONCLUSION Water diffusivity in a biological tissue is affected by many microstructural determinants, such as cellularity, viscosity, permeability and histologic architecture. In DWI, only the magnitude of water diffusion is taken into account, and can be expressed quantitatively by the ADC value. DTI is a more complicated technique, which takes into account not only the magnitude, but also the main direction and threedimensional shape of water diffusion; this information can be expressed in DTI derived metrics such as FA and MD. Quantitative assessment of cerebral white matter tracts is useful for the diagnosis, presurgical assessment and follow-up of patients with brain tumors. There is no doubt that MRI techniques such as DWI and DTI provide important information for surgical or treatment planning, especially about the anatomical relationship between the brain tumor and the adjacent fiber tracts. Up to now, it is impossible to accurately predict tumor grade and histology by MRI alone, despite promising trends which rely on analysis of ADC and FA values. Quantitative MRI techniques (such as DTI, DKI, FA mapping, fiber tracking etc.) are here to stay and hold great promise to detect and characterize brain tumors and other neurological disorders at an early stage.

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ADVANCED COURSES OF THE ESNR MEETING 2013

MR imaging in non-MS neuro-inflammation: granulomatous diseases Fabrice Bonneville

Neuroinflammation can be encountered in a large variety of pathological conditions. Multiple sclerosis is the most frequent, but non-MS inflammatory diseases still encompasses a wide spectrum of disorders including other demyelinating syndromes, infections and granulomatous diseases. The diagnosis of the latter is still based on clinical features and laboratory findings but in this setting, some MRI findings are indicative of each specific disease: micronodular leptomeningeal enhancement in sarcoidosis, diffuse or focal pachymeningeal

F. Bonneville Department of Neuroradiology, Toulouse University Hospital, Toulouse, France email: [email protected]

involvement in Wegener disease, dentate nuclei and brain stem lesions in Langerhans cell histiocytosis, meningeal masses, dentate nuclei lesions and periarterial infiltration in Erdheim-Chester disease, meningeal masses in Rosai-Dorfman disease, veinular pontic lesions and cerebral vein thrombosis in Behçet, supratentorial microvascular lesions in lupus and antiphospholipid and Gougerot-Sjögren syndrome. In this short presentation, the most suggestive MRI findings for each granulomatous disease will be explained, described and illustrated.

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MRI in focal, non-lesional epilepsy Susanne Knake

Approximately 60 % of all patients with epilepsy (0.4 % of the population in industrialized countries) suffer from focal epilepsy syndromes. About 15 % of these patients have medically intractable seizures and might be candidates for surgical epilepsy treatment. The goal of surgical treatment is seizure control by complete disconnection of the epileptogenic zone, which is defined as the area of tissue indispensable for the generation of clinical seizures

S. Knake Universitätsklinikum Standort Marburg Ag, Brain Imaging Epilepsiezentrum Marburg, Marburg, Germany email: [email protected]

under preservation of the eloquent cortex. MRI has become an extremely valuable tool for presurgical evaluation of epilepsy patients by enabling detection of the epileptogenic zone. Epilepsy surgery is challenging, if patients with focal epilepsies are MRI-negative. Here, we will review the contribution of novel and automated imaging techniques to better define the epileptogenic lesion in the clinical practice.

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ADVANCED COURSES OF THE ESNR MEETING 2013

Imaging in Parkinsonism and other extrapyramidal disorders Tatjana Stošić-Opinćal

INTRODUCTION Extrapyramidal disorders can be classified as pathologies that affect basal ganglia (caudate, putamen, and globus pallidus), subtalamic nucleus and structures that are functionally connected with them (substantia nigra) [1]. On histological level affected tissues exhibit high level of deposits of paramagnetic ions (presumably iron and copper) and loss of neural tissue [2]. In turn this is manifested in loss of volume of brain structures and dysfunction of specific neural tracts. Imaging techniques were focused on tracing of those changes.

METHODS Magnetic resonance imaging (MRI) in primary choice since it provides morphological, structural and physiological insight in changes caused by extrapyramidal disorders. Positron emission tomography (PET) gives additional information about physiological changes by using neurotransmitters labeled with positron emitters. Computerized tomography (CT) has limited possibilities which are restricted to assessment of morphological changes.

PARKINSONISM Parkinsonism refers to any condition that causes a combination of the movement abnormalities such as tremors, slow movement, impaired speech or muscle stiffness resulting from the loss of dopaminergic nerve cells in substantia nigra pars compacta. Beside idiopathic Parkinson’s disease (PD), a several conditions fulfill definition-such as progressive supranuclear palsy (PSP), multisystem atrophy (MSA-Parkinson and olivopontocerebelar atrophy) and corticobasal degeneration.

IDIOPATHIC PARKINSON’S DISEASE Computerized tomography and conventional (structural) MRI have limited role in diagnostics of idiopathic Parkinson’s disease. Brain atrophy, generalized or frontally predominant, which is characteristic T. Stošić-Opinćal Clinical Center of Serbia, Belgrade, Serbia email: [email protected]

of clinically advanced cases, can be assessed by these two techniques [3]. Those findings are non specific since a variety of neurological diseases show similar pattern. The more specific sign can be observed on T2 imaging of brain stem were narrowing of high intensity zone located between substantia nigra pars reticulata and red nucleus [4]. Despite of this, it is still difficult to detect abnormalities in the substantia nigra in individual patients in routine clinical scans. However, the role of structural techniques is in differentiation of PD from other Parkinson-like disorders. Advanced MRI techniques which probe tissue microstructure provide more information and introduce more parameters suitable for early diagnostics of PD. T2* relaxometry, method which exploits effect which iron exhibit on local magnetic field, pinpoints to presence of higher levels of iron in substantia nigra [5]. Findings on diffusion weighted imaging (DWI) are restricted to increased diffusivity in olfactory tract (consequence of hypoosmia), which could be considered as specific for PD [6]. Diffusion tensor imaging studies, which exploit anisotropy of water diffusion in evaluation of integrity of nerve tracts, revealed decreased fractional anisotropy (FA) and increased mean diffusivity in the substantia nigra and the lower part of the putamen/caudate complex [7]. These findings suggest loss of tract integrity. Determination of concentration of N-acetyl aspartate (NAA, which is considered as marker of neuron density) by use of magnetic resonance spectroscopy (MRS) usually doesn’t reveal differences between striatum of PD and normal subjects [8]. Use of functional magnetic resonance imaging (fMRI) and motor stimulation shows hypoactivation in supplementary motor cortex and hyperactivation of other cortical motor regions, such as the lateral premotor cortex and parietal cortex in PD patients [9]. Numerous volumetric studies based on MRI images revealed atrophy of hippocampal region, medial temporal lobe and prefrontal cortex. For patients with concomitant dementia atrophy was also noticed in anterior cingulate, thalamus, caudate and different regions of cortical gray matter [10]. However, didn’t find any differences between volumes of substantia nigra in patients and healthy subjects. Therefore, volumetric methods found application in evaluation of time course of PD. Application of PET, with use of dopamine labeled with positron emitter 18 F as tracer, confirms degeneration of striatonigral pathway. This finding is highly specific for loss of dopaminergic neurons [11}. However, studies using 18F-deoxiglucose (FDG) didn’t revealed impaired metabolism in striatum or substantia nigra [12].

Neuroradiology (2013) 55 (Suppl 1):S15–S159 PROGRESSIVE SUPRANUCLEAR PALSY (PSP) Convenional MRI has major role in diagnostics of progressive supranuclear palsy. Characteristic atrophy of rostral midbrain segment can be noticed on T1W images (humming bird sign-see Fig 1) is accompanied by dilatation of cerebral aqueduct and enlarged perimesocenphalic cisterna which can be seen on T2 images. Multiple cerebral infarcts were found in one-third of patients [13]. These diagnostic signs enable clear distinction between late stages of PSP and idiopathic Parkinson’s disease. However, for distinction in earlier phases of disease DWI, DTI and volumetric measurements should be used. Volumetric measurements revealed atrophy of cerebellar cortex, the thalamus, the putamen, the pallidum, the hippocampus and the brainstem in PSP [14], accompanied by enlargement of 3rd and 4th ventricle.

Figure 1. Sagital T1w MPRAGE in patient suffering from PSP. The atrophy of midbrain is denoted by arrow (“humming bird sign”).

Figure 2. a) Axial T2w MRI in patient suffering from MSA. Arrow indicates “hot bun cross sign”, b) Slit-void sign (arrow) on T2W image in MSA. Findings that could be usually seen on DWI images include increased apparent diffusion coefficient (ADC) in structures of basal ganglia [15]. Magnetic resonance spectroscopy suggests presence of reduced levels of NAA in putamen in PSP patients [16]. MULTISYSTEM ATROPHY MSA is subcategorized into three syndromes by predominant automatic dysfunction (MSA-A), predominant Parkinsonism

S139 (MSA-P), and predominant cerebellar ataxia (MSA-C). The pathologic substrate of these three syndromes is mainly located in the spinal cord, putamen, brainstem and cerebellum. Because MRI cannot trace changes in the intermediolateral columns of the spinal cord, diagnostics is focused on last two. Classical MRI identifies sites of maximum atrophy in the brain stem and cerebellum. On T2w images middle cerebellar peduncle shows the most marked reduction in size, but other affected structures include the cerebellar vermis, the cerebellar hemispheres, the pons and the lower brain stem. Signal hyperintensities can be identified within the pons, middle cerebellar peduncles (“hot bun cross” sign-see fig. 2a) and putamen. Usual finding on T2W images in putamen is presence of slit-like area of hypointesity, surrounded by hyperinensive region (fig 2b) [17]. Studies which involved ADC measurement in this structure revealed increased density compared to healthy controls [6]. Usual finding in MRS spectra is reduction of NAA in putamen, which is consistent with neuronal loss/dysfunction [16]. CORTICOBASAL DEGENERATION CBD is characterized by asymmetric frontoparietal atrophy mostly involving the contralateral side of the more clinically affected body side. Other features noticeable on T2W images include putaminal hypointensity and hyperintense signal changes in the motor cortex or subcortical white matter [1]. OTHER EXTRAPYRAMIDAL DISORDERS Wilson’s disease Wilson's disease is inherited as an autosomal recessive trait characterized by abnormal metabolism of copper in liver and consequent neurodegeneration. Imaging is of value in demonstrating the particular changes occurring in the brain [18]. CT can demonstrate ventricular dilatation and cortical atrophy as well as hypodensities in the basal ganglia [1]. MRI is more sensitive in detecting both lesions within the basal ganglia and in the thalamus. Usual MRS findings are reduction of NAA and increase in glutamine/glutamate concentrations, which could be explained by nerve loss and increased excitability of tissue [18]. Huntington disease Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder, caused by a CAG repeat expansion in the gene encoding the protein huntingtin. The availability of a sensitive and specific genetic test allows pre-clinical diagnosis, many years before the onset of unequivocal motor signs. CT reveals evidence of cortical and basal ganglia atrophy. A measure of caudate nuclear size (the bicaudate diameter) shows significant differences compared with a control population. The caudate and putaminal atrophy are better defined by MRI. In the classical form of the disease, abnormal signals from these nuclei are unusual. In the akinetic–rigid form, however, T2-weighted images demonstrate increased signal intensity in both the caudate and the putamen [19]. PANTOTHENATEKINASE-ASSOCIATED NEURODEGENERATION (HALLERVORDEN–SPATZ DISEASE) Hallervorden-Spatz disease is caused by mutation in gene which code protein called pantothenate kinase 2 responsible which takes part in regulation of vitamine B5 metabolism. Patients with this genetic defect have a buildup of iron in parts of the brain. MRI findings are characteristic, with diffuse low signal intensity on T2-weighted images in the globus pallidus, accompanied by an anteromedial area of high signal intensity (“eye-of-the-tiger” sign) [20]. However, this may be occasionally seen in patients with corticobasal degeneration. CONCLUSION Diagnostics of extrapyramidal disorders and distinguishing among them requires multimodal approach, which beside classical CT and MRI include physiological imaging (MRS and PET), volumetric evaluation of brain structures atrophy and assessment of integrity of nerve fibers (DWI and DTI).

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Wu, T. and Hallett, M.A., (2008), ‘Biomarkers-MRI’ in Parkinson's Disease: Diagnosis & Clinical Management, Demos, New York Wayne-Martin, W. R and Broderick P. A., (2005), Bioimaging in Neurodegeneration (Contemporary Neuroscience),. Humana Press, New Jersey Martin, W. R. (2001), 'Magnetic resonance imaging and spectroscopy in Parkinson's disease.', Adv Neurol 86, 197–203. Doraiswamy, P. M.; Shah, S. A.; Husain, M. M.; Escalona, P. R.; McDonald, W. M.; Figiel, G. S. & Krishnan, K. R. (1991), 'Magnetic resonance evaluation of the midbrain in Parkinson's disease.', Arch Neurol 48(4), 360. Baudrexel, S.; Nürnberger, L.; Rüb, U.; Seifried, C.; Klein, J. C.; Deller, T.; Steinmetz, H.; Deichmann, R. & Hilker, R. (2010), 'Quantitative mapping of T1 and T2* discloses nigral and brainstem pathology in early Parkinson's disease.', Neuroimage 51(2), 512–520. Köllensperger, M.; Seppi, K.; Liener, C.; Boesch, S.; Heute, D.; Mair, K. J.; Mueller, J.; Sawires, M.; Scherfler, C.; Schocke, M. F.; Donnemilier, E.; Virgolini, I.; Wenning, G. K. & Poewe, W. (2007), 'Diffusion weighted imaging best discriminates PD from MSA-P: A comparison with tilt table testing and heart MIBG scintigraphy.', Mov Disord 22(12), 1771–1776.

Schocke, M. F. H.; Seppi, K.; Esterhammer, R.; Kremser, C.; Mair, K. J.; Czermak, B. V.; Jaschke, W.; Poewe, W. & Wenning, G. K. (2004), 'Trace of diffusion tensor differentiates the Parkinson variant of multiple system atrophy and Parkinson's disease.', Neuroimage 21(4), 1443–1451. [8] Abe, K.; Terakawa, H.; Takanashi, M.; Watanabe, Y.; Tanaka, H.; Fujita, N.; Hirabuki, N. & Yanagihara, T. (2000), 'Proton magnetic resonance spectroscopy of patients with parkinsonism.', Brain Res Bull 52(6), 589–595. [9] Eidelberg, D. & Edwards, C. (2000), 'Functional brain imaging of movement disorders.', Neurol Res 22(3), 305–312. [10] Ghaemi, M.; Hilker, R.; Rudolf, J.; Sobesky, J. & Heiss, W.-D. (2002), 'Differentiating multiple system atrophy from Parkinson's disease:

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contribution of striatal and midbrain MRI volumetry and multi-tracer PET imaging.', J Neurol Neurosurg Psychiatry 73(5), 517–523. Antonini, A.; Vontobel, P.; Psylla, M.; Günther, I.; Maguire, P. R.; Missimer, J. & Leenders, K. L. (1995), 'Complementary positron emission tomographic studies of the striatal dopaminergic system in Parkinson's disease.', Arch Neurol 52(12), 1183–1190. Otsuka, M.; Ichiya, Y.; Kuwabara, Y.; Hosokawa, S.; Sasaki, M.; Yoshida, T.; Fukumura, T.; Kato, M. & Masuda, K. (1996), 'Glucose metabolism in the cortical and subcortical brain structures in multiple system atrophy and Parkinson's disease: a positron emission tomographic study.', J Neurol Sci 144(1-2), 77–83. Savoiardo, M.; Girotti, F.; Strada, L. & Ciceri, E. (1994), 'Magnetic resonance imaging in progressive supranuclear palsy and other parkinsonian disorders.', J Neural Transm Suppl 42, 93–110. Schulz, J. B.; Skalej, M.; Wedekind, D.; Luft, A. R.; Abele, M.; Voigt, K.; Dichgans, J. & Klockgether, T. (1999), 'Magnetic resonance imaging-based volumetry differentiates idiopathic Parkinson's syndrome from multiple system atrophy and progressive supranuclear palsy.', Ann Neurol 45(1), 65–74. Lodi, R. (2009), 'Diffusion-weighted brain imaging study of patients with clinical diagnosis of corticobasal degeneration, progressive supranuclear palsy and Parkinson's disease.', Brain 132(Pt 12), e130. Yanagihara, T. (2000), 'Proton magnetic resonance spectroscopy of patients with parkinsonism.', Brain Res Bull 52(6), 589–595. Pastakia, B.; Polinsky, R.; Chiro, G. D.; Simmons, J. T.; Brown, R. & Wener, L. (1986), 'Multiple system atrophy (Shy-Drager syndrome): MR imaging.', Radiology 159(2), 499–502. Alanen, A.; Komu, M.; Penttinen, M. & Leino, R. (1999), 'Magnetic resonance imaging and proton MR spectroscopy in Wilson's disease.', Br J Radiol 72(860), 749–756. Klöppel, S.; Henley, S. M.; Hobbs, N. Z.; Wolf, R. C.; Kassubek, J.; Tabrizi, S. J. & Frackowiak, R. S. J. (2009), 'Magnetic resonance imaging of Huntington's disease: preparing for clinical trials.', Neuroscience 164(1), 205–219. Angelini, L.; Nardocci, N.; Rumi, V.; Zorzi, C.; Strada, L. & Savoiardo, M. (1992), 'Hallervorden-Spatz disease: clinical and MRI study of 11 cases diagnosed in life.', J Neurol 239(8), 417–425.

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Delayed and chronic ischemia of the brain – an underestimated feature? M. Söderman

In order to function properly an adult human brain needs about 25 ml oxygenated blood per 100 g of tissue. In some situations the blood supply may be compromised even though no permanent damage has yet occurred. This state of functional impairment, “cerebral hypoperfusion”, may progress to permanent damage, stay more or less constant, or even regress, depending on many factors. The “penumbra” around an infarcted core is a familiar example of hypoperfusion1. In principle, the condition is reversible if blood flow can be restored. However, long-standing or severe flow impairment will create brain injury. The neurological symptoms vary according to which part of the brain is affected and the flow conditions. The Circle of Willis here plays a pivotal role. Cognitive symptoms are not uncommon and are probably often overlooked2. They may develop rapidly or insidiously, sometimes related to “watershed” infarctions in areas between vascular territories particularly vulnerable when perfusion is poor. In addition, other degenerative diseases may have a synergistic detrimental effect. Patients with high degree internal carotid artery (ICA) stenosis or occlusion frequently develop cognitive symptoms, even without brain infarction2. Superficial temporal artery to middle cerebral artery bypass has not been shown to improve the prognosis, possibly because of lack of technical success3. Trombendarterectomy or stenting of the ICA can improve cognitive function4,5. Recently, endovascular recanalization of the chronically occluded ICA has emerged as a promising therapy in patients where previously the only treatment option was surgical bypasses.

M. Söderman Ass. Professor Department of Clinical Neuroscience, Karolinska Institutet and Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden email: [email protected]

Perfusion imaging with CT or MRI gives little or no data about absolute blood flow or brain metabolism. Oxygen extraction fraction measurement with PET has been used but also questioned in the assessment of this patient group3. To summarize, delayed and chronic ischemia of the brain is most likely underestimated. The clinical awareness of this often quite elusive condition is low. Also, we need better tools to assess brain metabolism and to offer patients the best possible treatment. References [1] [2] [3]

[4] [5]

Heiss WD. The Ischemic Penumbra: Correlates in Imaging and Implications for Treatment of Ischemic Stroke. The Johann Jacob Wepfer Award 2011. Cerebrovasc Dis 2011;32(4):307–20. Marshall RS, Festa JR, Cheung YK, et al. Cerebral hemodynamics and cognitive impairment: baseline data from the RECON trial. Neurology 2012;78(4):250–5. Powers WJ, Clarke WR, Grubb RL, Jr., Videen TO, Adams HP, Jr., Derdeyn CP. Extracranial-intracranial bypass surgery for stroke prevention in hemodynamic cerebral ischemia: the Carotid Occlusion Surgery Study randomized trial. Jama 2011;306(18):1983–92. Hino A, Tenjin H, Horikawa Y, Fujimoto M, Imahori Y. Hemodynamic and metabolic changes after carotid endarterectomy in patients with highdegree carotid artery stenosis. J Stroke Cerebrovasc Dis 2005;14(6):234–8. Lal BK, Younes M, Cruz G, Kapadia I, Jamil Z, Pappas PJ. Cognitive changes after surgery vs stenting for carotid artery stenosis. J Vasc Surg 2011;54(3):691–8.

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Clinical and neuropsychological findings in patients with hemodynamic ischemia Helmuth Steinmetz

The parenchymal brain arteries can be subdivided into the (i) superficial pial (centrifugal) system and (ii) the deep penetrating (centripetal) system. Borderzones or watersheds exist between the territories of each large pial artery (e.g. anterior, middle and posterior cerebral artery), as well as between the centrifugal and centripetal system (“inner borderzones”). Each of the corresponding borderzone or watershed infarctions has a characteristic, although not entirely specific neuroradiologic appearance. Neurological syndromes particularly suggestive for hemodynamic mechanisms include “limb shaking”, “retinal claudicatio”, the “opticoretinal syndrome” (internal carotid artery, respectively), the “man-in-the-barrel” syndrome (anterior/middle cerebral arteries bilat-

H. Steinmetz Department of Neurology, Center of Neurology and Neurosurgery, Goethe University Frankfurt am Main email: [email protected]

erally) or Balint’s syndrome (posterior/middle cerebral arteries bilaterally). In addition to such clinical pictures, a hemodynamic origin is also sometimes suggested by characteristic circumstances of symptom occurrence, such as rising to the upright position, postprandial blood pressure drop, physical exercise or coughing. In contrast, a specific pattern of neuropsychological deficits suggesting hemodynamic impairment has not been established. One recent randomized study (RECON/COSS) of extra-intracranial-bypass-surgery in patents selected by positron emission tomography (increased oxygen extraction fraction) failed to show improvement of cognitive functions. Thus, despite more mechanistic concepts, it remains unlikely that vascular cognitive impairment can be ameliorated by hemodynamic treatment.

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Imaging patterns of ischemic lesions and differential diagnosis Bernhard Schuknecht

Chronic ischemia may present as white matter lesions (WML) and/or as cortical infarcts. The imaging correlate is increased signal intensity on T2 weighted and Flair MR sequences and on CT white matter and cortical hypodensity. Imaging-histologic correlation have shown white matter lesions to correspond to axonal loss, demyelination, astrocytic gliosis and enlarged perivascular spaces. On MR imaging white matter lesions may be small and focal, coalesce to larger areas and combine with lacunar infarcts of deep white and gray matter. The lesion distribution and extent and age-related progression of white matter changes have been the subject of different rating scales (among others Fazekas et al., Wahlund et al.) to enable quantification and assess evolution over time and to provide a comparison between CT and MR studies. An increase in thr number and extension of white matter lesions is observed ranging from approximately 10 % of individuals affected in the fourth decade to up to 80 % of individuals in the eighth decade of life. Few punctate supratentorial lesions commonly are nonspecific. Significant overlap exists between normal and an abnormal degree of white matter lesions. Isolated punctate or multiple non-confluent lesions in the subcortical white matter are nonspecific, sparing of commissural fibers and of the infratentorial white matter is obligatory. On follow-up after 6 years punctate white matter lesions were found to be not progressive and thus considered benign (Schmid). However, early confluent and marked confluent white matter abnormalities were progressive. Thus lesion grade at baseline was the only significant predictor of lesion progression. Intracranial small vessel atherosclerosis is the leading cause of an increased extent of white matter lesions corresponding to leukencephalopathy in the advanced stage. Leukencephalopathy initially predominantly affects the periventricular white matter, subsequently extends into the deep centrum semiovale and optic radiation and only in late stages involves subcortical fronto-parietal and subinsular U-fibers. Subcortical involvement is more common in patients with poorly controlled diabetes mellitus and cerebral amyloid angiopathy. In the latter instance cortico-subcortical “peripheral“ microbleeds are observed on SWI or T2* sequences. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukencephalopathy (CADASIL) also has a predominant subcortical temporo-polar and superior frontal white matter predilection. White matter lesion location in the pons and adjacent to the basal ganglia is indicative of chronic and excessive hypertension and typically associated with “central” microbleeds on susceptibility sensitive sequences. B. Schuknecht Medical Radiologic Institutes MRI, Zurich, Switzerland email: [email protected];bschuknecht@ mri-roentgen.ch

While pathological substrates of white matter lesions are heterogeneous in nature and severity, cortical and deep grey matter lesion location is universally pathologic and corresponds to infarcts. Hemodynamic and thromboembolic infarcts frequently occur in conjunction though pathogenically different. Patients with single vessel stenosis harbour more infarcts in the perforating branches of the middle cerebral artery (MCA). Conversely patients with concurrent extra- intracranial stenosis are more likely to develop cortical infarcts (Man BL). Small embolic infarcts are more common on the convexity of a gyrus and thus differ from hemodynamic infarcts that predominantly affect the depth of a sulcus. Watershed infarcts represent deep multifocal white matter lesions or lacunes in a straight line pattern at the junction between basal perforating branches and penetrating pial vessels. Pure deep watershed infarcts however are rare (0.8 %). A frequent combination is in conjunction with lacunar and pial infarcts (58.5 %) and rarely with pial infarcts only (7 %). Additional manifestations of ischemia include sequela of vasoconstrictive syndromes such as PRESS or RCVS, autoimmune microvascular occlusive disorders and further vascular inflammatory conditions. The differential diagnosis includes additional hereditary vascular (CADASIL, MELAS, Fabry, xerebrotendinous xanthomatosis), inflammatory/autoimmune vascular (PACNS, APS, SLE) disorders, infectious/ post infectious conditions (TB, HIV,varicella zoster vasculits), leukencephalopathies and toxic- metabolic conditions such as radio-chemotherapy. Conclusion: Morphologic imaging may suggest chronic white lesions and grey matter infarcts at least initially as a focal rather than diffuse cerebrovascular process. Advanced applications such as perfusion MR and CT and diffusion tensor imaging enable deleineation of “whole brain “perfusion and tissue microstructure and are thus on the wake to bridge the gap to the frequently discrepant clinical presentation. CT and or MR angiography are essential in chronic disease as well to provide information on the location and extent of an underlying disease of the intra- and extracranial macrocirculation.

1. Fazekas F et al. MR signal abnormalitiess at 1.5 T in Alzheiemr`s dementia and normal aging AJR 1987 149 351–356 7 2. Wahlund LO et al. A New Rating Scale for Age-Related White Matter Changes Applicable to MRI and CT. Stroke. 2001; 32: 1318–1322 3. Schmid R et al. Progression of cerebral white matter lesions: 6-year results of the Austrian Stroke Prevention Study Lancet 2003;361: 2046–2048

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Challenges of Brain Perfusion Measurement Max Wintermark

Introduction: the need for standardization and validation Since iv tPA was approved in 1996, the number of acute stroke patients receiving this treatment has stayed under 5 % in most locations, mainly because of delayed presentation to care {{27 Bambauer,K.Z. 2006; }}. A recent study suggested that the time window for tPA administration could be extended from 3 hours to 4.5 hours in certain patients {{151 Hacke,W. 2008; }}. While this extension might slightly increase the rate of tPA administration, it does not change the fundamental limitation that we currently decide on thrombolytics administration using a generalized, statistical rule regarding time to presentation rather than an individualized, pathophysiological assessment of the "ischemic penumbra", which is the target of the tPA treatment. Several studies {{14 Albers,G.W. 2006; }} {{29 Furlan,A.J. 2006; }} {{28 Hacke,W. 2005; }} have suggested and validated the concept that the ischemic penumbra can be imaged and quantified, and an optimal therapeutic decision regarding thrombolytic agents can be based on such imaging, within an extended time window of up to 9 hours. Such approximation would not only increase the fraction of acute stroke patients amenable to thrombolytic treatment - possibly up to 40 % - but also select them more precisely, thereby improving overall clinical outcomes {{26 Schellinger,P.D. 2004; }}. However, this concept of penumbral image-guided thrombolytic therapy has not been validated in a large phase III trial yet {{115 Davis,S.M. 2008; }} {{58 Hacke,W. 2009; A trial of imaging selection and endovascular treatment for ischemic stroke. Kidwell CS, Jahan R, Gornbein J, Alger JR, Nenov V, Ajani Z, Feng L, Meyer BC, Olson S, Schwamm LH, Yoo AJ, Marshall RS, Meyers PM, Yavagal DR, Wintermark M, Guzy J, Starkman S, Saver JL; MR RESCUE Investigators.N Engl J Med. 2013 Mar 7;368(10):914–23. doi: 10.1056/NEJMoa1212793. Epub 2013 Feb 8} and as a result has not become part of the clinical standard-of-care in tPA treatment decisions. One of the reasons for this is the lack of standardization in penumbral imaging, which can result in different treatment decisions in the same patient when different penumbral imaging methods are used {{158 Leiva-Salinas, C. 2010; }}. Current methods available for defining the penumbra vary due to several reasons. The mathematical algorithms that calculate variables such as cerebral blood volume (CBV) , cerebral blood flow (CBF) and mean transit time (MTT) differ. The variables that are used to define the penumbra (for example, MTT versus M. Wintermark Associate Professor of Radiology, Neurology, Neurological Surgery and Biomedical Engineering Chief of Neuroradiology University of Virginia, Department of Radiology, Charlottesville,VA,USA email: [email protected]

CBF versus CBV in perfusion-CT imaging) and their corresponding thresholds (for example, the threshold of perfusion/diffusion mismatch in MRI imaging) may also differ {{113 Provenzale,J.M. 2008; Dani KA, Thomas RG, Chappell FM, Shuler K, MacLeod MJ, Muir KW, Wardlaw JM; Translational Medicine Research Collaboration Multicentre Acute Stroke Imaging Study. Computed tomography and magnetic resonance perfusion imaging in ischemic stroke: definitions and thresholds. Ann Neurol. 2011 Sep;70(3):384–401.}} (Figures 1 and 2). The imaging methods to identify the ischemic penumbra differ from each other, but not in an irreconcilable way. Rather, they just need some tuning up in order to give concordant results. This is one of the goals pursued by the Stroke Imaging Repository (STIR) Consortium {{Stroke Imaging Repository Home found at http://stir.ninds.nih.gov/. The Stroke Imaging Repository (STIR) On September 2007, the National Institute of Health, in conjunction with the American Society of Neuroradiology and the Neuroradiology Education & Research Foundation, sponsored a research symposium entitled Advanced NeuroImaging for Acute Stroke Treatment. That meeting brought together stroke neurologists, neuroradiologists, emergency physicians and neuroimaging research scientists to discuss the role of advanced neuroimaging in acute stroke treatment. In particular, the goals of the meeting were to debate about some unresolved issues regarding: (1) the standardization of perfusion and penumbral imaging techniques, (2) the validation of the accuracy and clinical utility of imaging markers of the ischemic penumbra, and (3) the validation of imaging biomarkers relevant to clinical outcomes {{31 Wintermark,M. 2008; }}. This meeting resulted into the creation of the Stroke Imaging Research (STIR) consortium, an international consortium of investigators to combine efforts to promote excellence in stroke care and stroke trial design and more specifically to overcome the issues mentioned earlier {{31 Wintermark,M. 2008; }}. STIR has developed a repository of source MRI and CT images toward the objectives of standardization and validation of acquisition, analytic, and clinical research methods of image-based stroke research. This consortium is working in close collaboration with another collaborative group, VISTA (Virtual International Stroke Trials Archive). VISTA is an international collaborative venture that was established to facilitate the planning of randomized clinical trials. The VISTA collaboration seeks to get together data sets from different institutions. The VISTA database provides the possibility to access a large volume of patient data on which to perform original analyses that would ultimately aid clinical trial design and development {{152 Ali,M. 2007; }}. In its second roadmap (Max Wintermark, Gregory W. Albers, Joseph P. Broderick, Andrew M. Demchuk, Jochen B. Fiebach, Jens Fiehler, James C. Grotta, Gary Houser, Tudor G. Jovin, Kennedy R. Lees, Michael H. Lev, David S. Liebeskind, Marie Luby, Keith W. Muir, Mark W. Parsons,

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Rüdiger von Kummer, Joanna M. Wardlaw, Ona Wu, Albert J. Yoo, Andrei V. Alexandrov, Jeffry R. Alger, Richard I. Aviv, Roland Bammer, Jean-Claude Baron, Fernando Calamante, Bruce C. V. Campbell, Trevor C. Carpenter, Søren Christensen, Colin P. Derdeyn, E. Clarke Haley Jr, Pooja Khatri, Kohsuke Kudo, Maarten G. Lansberg, Lawrence L. Latour, Ting-Yim Lee, Richard Leigh, Weili Lin, Patrick Lyden, Grant Mair, Bijoy K. Menon, Patrik Michel, Robert Mikulik, Raul G. Nogueira, Leif Østergaard, Salvador Pedraza, Christian H. Riedel, Howard A. Rowley, Pina C. Sanelli, Makoto Sasaki, Jeffrey L. Saver, Pamela W. Schaefer, Peter D. Schellinger, Georgios Tsivgoulis, Lawrence R. Wechsler, Philip M. White, Greg Zaharchuk, Osama O. Zaidat, Stephen M. Davis, Geoffrey A. Donnan, Anthony J. Furlan, Werner Hacke, Dong-Wha Kang, Chelsea Kidwell, Vincent N. Thijs, Götz Thomalla, Steven J. Warach. For the Stroke Imaging Research (STIR) and VISTA-Imaging Investigators. Acute Stroke Imaging Research Roadmap II. Stroke (in press)), STIR proposes the establishment of a calibration process for measuring ischemic core and penumbral software, as well as the population of the STIR clinical and imaging data repository to facilitate this calibration process. STIR recognizes that imaging techniques continuously evolve, and that there will always be a newer, better ischemic core or penumbral imaging technique or processing software. Therefore, it is desirable to find a balance between continued attempts to improve on existing methods versus determining whether existing methods are good enough to be used in current clinical trials. At this time, STIR does not assess or recommend how to use ischemic core and penumbra information for prognosis, prediction of response to treatment and/or selection of patients for reperfusion therapy. These are better answered in welldesigned clinical trials or prospective validation studies. Conclusion STIR aims at facilitating the validation and widespread use of imaging for acute stroke patients’ management. Contributions to the central repository from academic institutions is crucial to obtain a large and complete dataset to but also to constitute a broad network of international stroke care centers that will – with the collaboration of the NIH, FDA and the industry- form the basis for future imaging-based stroke trials, including, but not limited to, treatment of stroke patients in an extended time window. Figures Figure 1. Depiction of the effect of varying the threshold on the size of the predicted infarct core in an 81 year-old woman with acute left MCA territory infarct treated successfully with tPA. Non contrast CT of the head obtained 2.5 hours after symptom (NCT) onset shows no findings. Perfusion CT parametric maps show a mismatch between the region with prolonged MTT (involving the anterior superficial left MCA territory) and the region of decreased CBV (limited to the left putamen), which represents the predicted infarct core. Follow-up non-contrast CT performed 36 hours later shows that the final infarct corresponds to the area of predicted infarct core as represented by the area of decreased CBV. Perfusion CT prognostic maps generated using different CBV thresholds (1.5, 2.0, 2.3 and 2.6 ml/100 g respectively) show that the volume of the predicted infarct core (in red) in case of recanalization varies depending on the chosen value. The CBV value that best predicts the size of the final infarct is 2.0 ml/100 g, as published in the literature.

S145 The threshold for the delineation of the ischemic penumbra (in green) was set as a relative 145 %.

Figure 2. Depiction of the effect of using different commercial PCT software packages (1, 2 and 3) on the MTT, CBV and CBF parametric maps in the same patient as in figure 1. Even if the discordance is not major nor is it incongruous, the area of predicted ischemic penumbra as represented by the area of prolonged MTT differs slightly depending on the software employed to process the source images,. The area of predicted infarct core as represented by the area of decreased CBV is very similar for all of the 3 manufacturers’ tools. Note that parametric maps from manufacturer 1 and 3 are displayed with vessels removed.

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Management of haemodynamic ischaemia; which evidence do we have? L. Jaap Kappelle

Treatment of patients with presumed haemodynamic cerebral ischaemia is largely based on clinical experience and not on evidence based medicine. So far, the few randomised controlled trials (RCT’s) of specific treatment options for patients with signs or symptoms of cerebral ischaemia of presumed haemodynamic origin have not shown any positive results.[1] As with patients with transient ischaemic attacks (TIAs) or ischaemic stroke in general, antithrombotic agents should be administered and hyperlipidaemia and diabetes mellitus should be rigorously controlled. Cessation of smoking should be actively pursued. Only the management of blood pressure might be different. Non-surgical treatment Blood pressure control Because clinical manifestations of cerebral ischaemia can be precipitated by the lowering of blood pressure in patients with occlusive arterial disease,[2,3] treatment of hypertension in patients with a TIA or ischaemic stroke of presumed haemodynamic origin should be done with caution, particularly in the acute phase. Sometimes hypertension should not be treated, and it might even be necessary to increase the blood pressure. In our experience and that of others,[4] tapering of antihypertensive drugs can result in cessation of recurrent TIAs in patients with internal carotid (ICA) occlusion and haemodynamic TIAs. In individual cases, we have sometimes had to accept systolic blood pressures as high as 200 mm Hg, at least temporarily. In the chronic phase, we advise control of blood pressure in the same way as for patients with TIA and stroke in general. Because patients with haemodynamic TIAs and ischaemic stroke might be particularly vulnerable to changes in blood pressure, calcium-channel blockers might be preferred over other classes of antihypertensive drugs to avoid fluctuations in blood pressure.[5] Bed rest In patients with recent and multiple ischaemic events precipitated by rising, we suggest bed rest for a few days. If the symptoms have not recurred in the meantime, we then generally advise the patient to gradually resume sitting positions, standing, and walking over several days. This approach has never been tested in an RCT. Revascularisation surgery Extracranial–intracranial bypass Superficial temporal artery (STA)–middle cerebral artery (MCA) bypass does not prevent recurrent ischaemic stroke in patients with TIAs or minor stroke associated with ICA occlusion or MCA stenosis, or occlusion in general.[6,7] The Carotid Occlusion Surgery Study (COSS) addressed the question of whether the STA–MCA bypass can prevent recurrent ischaemic stroke in a subgroup of patients with recently symptomatic ICA occlusion and documented misery perfusion, as determined L. J. Kappelle Stroke Centre, University Medical Centre, Utrecht, The Netherlands email: [email protected]

by an increased oxygen extraction fraction (OEF) on positon emission tomography (PET).[8] The primary outcome event was the combination of (1) all stroke and death from surgery through 30 days after surgery and (2) ipsilateral ischemic stroke within 2 years of randomization. Ninetyseven patients were randomized to the surgical group and 98 to the medical group. The trial was stopped early by the US National Institutes of Health for futility. STA-MCA bypass surgery plus medical therapy (primary endpoint 21 %) compared with medical therapy alone (primary endpoint 22,7 %) did not reduce the risk of recurrent ipsilateral ischemic stroke at 2 years.[9] The STA-MCA arterial bypass patency rate was 98 % at the 30-day postoperative visit and 96 % at the last follow-up examination. Postoperative stroke rate was 15 %.[10] The main criticism to the COSS was the high complication rate of surgery that might have been caused by the low case-volume per surgeon and per centre, because the 93 patients were operated by 30 different surgeons.[11] Another explanation for the failure of COSS might be failure of the semiquantitative, hemispheric OEF ratio method, because this method did not identify the same group of patients as did quantitative OEF using a threshold of 50 %.[12] The results of a Japanese trial have provided evidence for a beneficial effect of the STA–MCA bypass in 196 patients with ICA or MCA occlusive disease and haemodynamic cerebral ischaemia according to quantitative cerebral blood flow measurements.[13] The second interim analysis showed that five surgically treated patients had a recurrent stroke versus 14 patients who were treated medically (p=0•046).89 The final results have not been published in the English literature. The Excimer laser-assisted non-occlusive anastomosis (ELANA) extracranial–intracranial bypass is a laser assisted bypass procedure that enables the construction of an anastomosis with the distal ICA or proximal MCA or anterior cerebral artery, without the need to temporarily clamp the recipient vessel.[14–16] This technique results in a bypass with a higher flow than can be achieved with the conventional STA–MCA technique,[17] and in theory might better protect against future ischaemic stroke. An RCT to determine the efficacy of the ELANA bypass in prevention of stroke has not yet been done. According to current clinical standards, STA–MCA or ELANA bypass operations to prevent ischaemic stroke in occlusive arterial disease should ideally be performed only in the context of a clinical trial. Nevertheless, one can occasionally consider STA–MCA or ELANA bypass surgery in patients with extracranial ICA occlusion and continuing ischaemic events in whom the arguments for a haemodynamic cause are compelling and in whom there are no other treatment options.[16,18] In patients with a chronic ocular ischaemic syndrome and ICA occlusion, the efficacy of bypass surgery in addition to medical therapy and panretinal photocoagulation to prevent progression to blindness is uncertain. Disappointing and good results have been reported.[19,20] In patients with cognitive deficits associated with ICA occlusion, there is too little evidence to recommend surgery to construct an extracranial– intracranial bypass, although beneficial results have been published.[21].

Neuroradiology (2013) 55 (Suppl 1):S15–S159 In the absence of an appropriate donor vessel for extracranial–intracranial bypass, as might be the case in patients with common carotid artery occlusion, a contralateral donor vessel can be used with tunnelling of the bypass over the skull (so-called “bonnet bypass”).[22–24] An intracranial–intracranial bypass is also possible with the ELANA technique.[25] Information about the efficacy and risk of complications of these procedures is limited to case reports. The same applies to extracranial–intracranial bypass surgery for posterior circulation stroke.[16,26] Its efficacy in stroke prevention has not been studied in an RCT, and the risk of complications is higher than for anterior circulation bypasses.[26] Extracranial-intracranial bypass has been effective in young patients with Moyamoya vasculopathy and patients prior to occluding an intracranial artery to treat a brain aneurysm. It is still unknown why the bypass is effective in Moyamoya and much less effective (or ineffective) in patients with ICA occlusions in the neck.[27] Recently, aspirin resistance has claimed as a potential explanation for this difference.[28] Other revascularisation procedures Treatment of stenosis in blood vessels that are important for the collateral blood supply to the hemisphere on the side of the ICA occlusion has not been studied in a large clinical trial, and precise estimates of the risks of these procedures in patients with symptomatic ICA occlusion are not available.[1] However, endarterectomy of a contralateral ICA stenosis or ipsilateral external carotid artery (ECA) stenosis can be considered in patients with symptomatic ICA occlusion in whom these blood vessels are important for collateral blood supply. Similarly, treatment of stenosis in the brachiocephalic, subclavian, or vertebral arteries can be considered if the stenosis compromises the collateral blood supply. We showed a sustained benefit, at least in terms of blood flow to both hemispheres, after endarterectomy for contralateral ICA stenosis in patients with symptomatic ICA occlusion.[30] In patients with chronic ocular ischaemic syndrome associated with ICA occlusion, endarterectomy of a stenotic ECA might be considered, because the eye might be dependent on the ECA.[1]

S147 results of the Carotid Occlusion Surgery Study. J Neurosurg. 2013; 118: 25–33. 11.

Hänggi D, Steiger HJ, Vajkoczy P; Cerebrovascular Section of the European Association of Neurological Surgeons (EANS). EC-IC bypass for stroke: is there a future perspective? Acta Neurochir (Wien). 2012; 154:1943–4.

12.

Carlson AP, Yonas H, Chang YF, Nemoto EM. Failure of cerebral hemodynamic selection in general or of specific positron emission tomography methodology?: Carotid Occlusion Surgery Study (COSS). Stroke. 2011; 42: 3637–9.

13.

JET Study Group. Japanese EC-IC Bypass Trial: the second interim analysis [in Japanese]. Surg Cereb Stroke 2002; 30: 434–37.

14.

92 Tulleken CAF, van der Zwan A, Verdaasdonk RM, Mansvelt Beck RJ, Moreira Pereira Ramos L, Kappelle LJ. High-fl ow Excimer laserassisted extra-intracranial and intra-intracranial bypass. Oper Tech Neurosurg 1999; 2:142–48.

15.

Langer DJ, Vajkoczy P. ELANA: Excimer laser-assisted nonocclusive anastomosis for extracranial-to-intracranial and intracranialtointracranial bypass: a review. Skull Base 2005; 15: 191–205.

16.

Sia SF, Morgan MK. High flow extracranial-to-intracranial brain bypass surgery. J Clin Neurosci. 2013 ; 20:1–5.

17.

van der Zwan A, Tulleken CAF, Hillen B. Flow quantifi cation of the non-occlusive Excimer laser-assisted EC-IC bypass. Acta Neurochir (Wien) 2001; 143: 647–54.

18.

Klijn CJM, Kappelle LJ, van der Grond J, van Gijn J, Tulleken CAF. A new type of extracranial/intracranial bypass for recurrent haemodynamic transient ischaemic attacks. Cerebrovasc Dis 1998; 8: 184–87.

19.

Klijn CJM, Kappelle LJ, van Schooneveld MJ, et al. Venous stasis retinopathy in symptomatic carotid artery occlusion: prevalence, cause, and outcome. Stroke 2002; 33: 695–701.

20.

Kawaguchi S, Sakaki T, Morimoto T, Okuno S, Nishikawa N. Eff ects of bypass on ocular ischaemic syndrome caused by reversed fl ow in the ophthalmic artery. Lancet 1999; 354: 2052–53.

21.

Fiedler J, Přibáň V, Skoda O, Schenk I, Schenková V, Poláková S. Cognitive outcome after EC-IC bypass surgery in hemodynamic cerebral ischemia. Acta Neurochir (Wien). 2011; 153:1303–11.

22.

Spetzler RF, Roski RA, Rhodes RS, Modic MT. The “bonnet bypass”. Case report. J Neurosurg 1980; 53: 707–09.

23.

Zumofen D, Khan N, Roth P, Samma A, Yonekawa Y. Bonnet bypass in multiple cerebrovascular occlusive disease. Acta Neurochir Suppl 2008; 103: 103–07.

24.

Garrido E, Freed MH. Fatal complication of the “bonnet bypass”: case report. Neurosurgery 1983; 13: 320–21.

25.

Langer DJ, van der Zwan A, Vajkoczy P, Kivipelto L, van Doormaal TP, Tulleken CAF. Excimer laser-assisted nonocclusive anastomosis. An emerging technology for use in the creation of intracranialintracranial and extracranial-intracranial cerebral bypass. Neurosurg Focus 2008; 24: E6.

26.

Ausman JI, Diaz FG, Vacca DF, Sadasivan B. Superficial temporal and occipital artery bypass pedicles to superior, anterior inferior, and posterior inferior cerebellar arteries for vertebrobasilar insuffi ciency. J Neurosurg 1990; 72: 554–58.

27.

Caplan LR. Bypassing trouble. Arch Neurol. 2012; 69:518–20.

28.

Jussen D, Horn P, Vajkoczy P. Aspirin resistance in patients with hemodynamic cerebral ischemia undergoing extracranial-intracranial bypass surgery. Cerebrovasc Dis. 2013; 35:355–62.

29.

Rutgers DR, Klijn CJM, Kappelle LJ, Eikelboom BC, van Huff elen AC, van der Grond J. Sustained bilateral hemodynamic benefi t of contralateral carotid endarterectomy in patients with symptomatic internal carotid artery occlusion. Stroke 2001; 32: 727–34.

Literature 1.

Klijn CJM. Kappelle LJ. Haemodynamic stroke: clinical features, prognosis and management. Lancet Neurol 2010; 9: 1008–17.

2.

Hankey GJ, Gubbay SS. Focal cerebral ischaemia and infarction due to antihypertensive therapy. Med J Aust 1987; 146: 12–14.

3.

Rothwell PM, Howard SC, Spence JD, Carotid Endarterectomy Trialists’ Collaboration. Relationship between blood pressure and stroke risk in patients with symptomatic carotid occlusive disease. Stroke 2003; 34: 2583–90.

4.

Leira EC, Ajax T, Adams HP. Limb-shaking carotid transient ischemic attacks successfully treated with modifi cation of the antihypertensive regimen. Arch Neurol 1997; 7: 904–05.

5.

Rothwell PM, Howard SC, Dolan E, et al. Prognostic signifi cance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension. Lancet 2010; 375: 895–905.

6.

EC/IC Bypass Study Group. Failure of extracranial-intracranial arterial bypass to reduce the risk of ischemic stroke. Results of an international randomized trial. N Engl J Med 1985; 313: 1191–200.

7.

Fluri F, Engelter S, Lyrer P. Extracranial-intracranial arterial bypass surgery for occlusive carotid artery disease . Cochrane Database Syst Rev 2010; 2: CD005953.

8.

Grubb RL Jr, Powers WJ, Derdeyn CP, Adams HP Jr, Clarke WR. The Carotid Occlusion Surgery Study. Neurosurg Focus 2003; 14: e9.

9.

Powers WJ, Clarke WR, Grubb RL Jr, Videen TO, Adams HP Jr, Derdeyn CP; COSS Investigators. Extracranial-intracranial bypass surgery for stroke prevention in hemodynamic cerebral ischemia: the Carotid Occlusion Surgery Study randomized trial. JAMA. 2011; 306:1983–92.

10.

Grubb RL Jr, Powers WJ, Clarke WR, Videen TO, Adams HP Jr, Derdeyn CP; Carotid Occlusion Surgery Study Investigators. Surgical

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Neurointerventional revascularization techniques Jan Gralla

Acute ischemic stroke is one of the major sources of morbidity and mortality in the industrialized countries. The lifetime risk of stroke is estimated to be one in five for middle-aged women and one in six for men according to the Framingham Study. Outcome depends on the length of time between onset of symptoms and revascularization, the recanalization rate, and on whether or not intracranial hemorrhage occurs. A meta-analysis of 52 studies on thrombolysis outcome in 2066 patients showed that the chance of an independent life after stroke increases 4.4 times for patients with successful recanalization compared to patients without recanalization; mortality rate decreases four-fold. Recent studies have examined whether mechanical recanalization techniques can accelerate the process of recanalization, increase the recanalization rate, and even expand the window of opportunity. The presentation illustrates the evolution of the different mechanical thrombolysis and stenting techniques and their working principles for endovascular vessel recanalization and reviews the data on the outcome after acute stroke treatment. Mechanical thrombectomy – latest development Among various endovascular techniques, the recently introduced stent retriever (SR) mark a turning point in endovascular stroke treatment. Combining the advantages of temporary stenting with immediate flow restoration without the need for permanent implantation plus thrombectomy with definitive thrombus removal, stent retrieval devices offer a promising new treatment option for acute ischemic stroke. The devices are applied in a manner comparable to that of intracranial

J. Gralla Department of Interventional and Diagnostic Neuroradiology, University of Bern, Bern, Switzerland email: [email protected]

stents. Numerous variants of this device type are currently under development or in first clinical trials (TREVO, Concentric Medical, Mountain View, California, USA; 3D-Seperator, Penumbra, Alameda, California, USA; ReVive, Micrus, California, USA). The first dedicated combined flow restoration and thrombectomy device for acute stroke treatment was the Solitaire FR (ev3, Irvine, USA). The device is a modification of the Solitaire AB Neurovascular Remodelling Device, originally developed for stent-assisted treatment of wide-neck intracranial aneurysms. Within a short period of time, numerous studies have reported on the in-vivo and clinical application of the Solitaire FR for stroke treatment. Various prospective (TREVO II, SWIFT, STAR) and retrospective studies have illustrate high recanalization rates of 70-85 % in anterior circulation stroke. More importantly, the studies have shown high rates of favourable clinical outcome with these technique. The Solitaire device and the TREVO device have been compared in randomized controlled trials against the first generation of thrombectomy; the MERCI device. Both trials illustrated a significantly higher recanalization result and superior clinical results in the group of patients treated with SR. These results are of major importance when looking at the recent publication of negative RCT on endovascular stroke treatment (IMS 3, Synthesis, MR Rescue). Due to the late clearance of SR, none of these has included an reasonable number of patients using this novel technique and can therefore not conclude on results of SR thrombectomy.

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Carotid stenting in neuroradiology today: Standard or niche indication? Prof. Dr. Olav Jansen

Four prospective controlled randomized trials have evaluated carotid artery stenting (CAS) in comparison to carotid endarterectomy (CEA). The three European studies (SPACE, EVA 3S, ICSS) focused on patients with symptomatic carotid stenosis, the US-study CREST also included asymptomatic patients. The primary endpoint in all studies were ipsilateral stroke and death, in CREST myocardial infarct was also defined as a primary endpoint. Because of a similar study protocol the European studies are secondary evaluated in a metaanalysis (CSTC), with still upcoming results. While SPACE and CREST showed no significant differences between CAS and CEA the metaanlysis of all three European studies showed a significant better outcome after CEA vs. CAS. CREST demonstrated no significant difference between CEA and CAS neither in symptomatic nor in asymptomatic carotid stenosis. While there were several methodological defaults in all studies but specially in the European studies there are at least no final recommendations possible but a slight preference for CEA in symptomatic patients. For asymptomatic patients the data are more weak but prospective studies are on the way (ACST II, SPACE 2). The northamerican guidelines accept CAS as an alternative treatment in patients with carotid stenosis when treatment circumstances are equal to study-conditions. The german guidelines accept CAS when treating centers can document their experience and low complication rate (< 6 %). For patients with asymptomatic carotid stenosis there is still a major lack of evidence and no general recommendations can be done. Secondary analysis of study data (CSTC) have shown additional aspects that should be recommended in treatment decision. All studies

O. Jansen Institute of Neuroradiology, Kiel, Germany email: [email protected]

have shown that patient with higher age have a higher complication rate after CAS vs CEA. Analysis of technical factors demonstrated no benefit of protection devices but significant less complications with the use of closed cell stents. Despite the open discussion on the importance of CAS in the treatment of elective patients there is absolute need for CAS in patients with high grade carotid stenosis undergoing acute endovascular stroke treatment. It is suspected that up to 10 % of all acute stroke patients, who are treated endovascular, need acute CAS. References 1.

Ringleb PA, Allenberg J, Bruckmann H et al. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: a randomised non-inferiority trial. Lancet 2006;368(9543):1239–1247.Mas JL, Trinquart L, Leys D et al. End-

arterectomy Versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial: results up to 4 years from a randomised, multicentre trial. Lancet Neurol 2008;7(10):885–892. 2.

Silver FL, Mackey A, Clark WM et al. Safety of stenting and endarterectomy by symptomatic status in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST). Stroke 2011;42(3):675–680.

3.

International Carotid Stenting Study investigators. Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial. Lancet. 2010 Mar 20;375(9719):985–97

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Periinterventional stroke, hemorrhage and hyperperfusion: How to avoid and manage complications during and after revascularization Istvan Szikora

1 Introduction Recent clinical trials demonstrated controversial results of carotid and intracranial endovascular revascularization procedures. The negative results are generally considered as indication of the inferiority of those techniques as compared to surgical or medical alternatives. However, most of he negative results can be explained by periprocedural complications rather than by the failure of the treatment modality. The SPACE trial demonstrated a 0,51 % absolute difference in the 30 days stroke and death rate following carotid artery stenting (CAS) versus carotid endarterectomy (CEA) in favor of CEA [1]. However, in a 2 years follow up, there was no significant difference between the two groups regarding recurrent stroke [2]. Similarly, in the SAMMPRIS trial, 30days stroke and death rate was significantly higher in the stented group (14,7 %) than in the medical group (5,8 %). Yet after 30 days, the rate of repeat events was the same in both cohorts [3]. Subsequently, identifying those complications and finding methods to avoid them is crucial to re-establish the proper value of the techniques.

2 Potential complications of carotid and intracranial revascularization technique In general, periprocedural complications can be classified as thromboembolic, hemorrhagic and medical ones. Each of these may occur either during (intraprocedural) or after (postprocedural) the procedure. Preventive actions can be taken before, during or after the procedure.

used intravenously (500 mg) with a practically immediate effect. Unfortunately, resistance to both ASA and Clopidogrel is relatively frequent. A variety of tests are available for checking the effect of both ASA and Clopidogrel, the Verify Now point of care test is probably being the most commonly used one. Using aggregometry is recommended, although the value of in vitro testing is subject of significant debate [4]. In case of antiplatelet resistance, the dose should be doubled. If there is no response to the elevated dose, alternative medication should be selected (Ticlopidine, Prasugrel). Stent implantation without effective antiplatelet treatment in place should be avoided, even if the proper medication delays the procedure. 3.1.2 Intraprocedural anticoagulation Cervical and intracranial angioplasties are done under Heparine anticoagulation as most neuro-endovascular procedures. Like antiplatelet treatment, the effect of heparinization could and should be monitored, which can be easily and reliably performed using Activated Clotting Time (ACT) test, aiming for double normal values. 3.2 Embolic protection Distal embolization is considered the most common complication of endovascular revascularization procedures. Different embolic protection techniques are applied for carotid angioplasty, no such method is available for intracranial angioplasty. 3.2.1 Protected CAS

3 Ischemic complications

3.2.1.1 Distal protection devices

3.1 Antithrombotic medication

Although the clinical benefit of distal embolus protection filter devices (EPD) has never been proved in randomized trials, their application for CAS is generally believed to reduce the number of embolic complications. This practice is in fact subject to debate. Even though the theory behind their use is very simple, their efficacy is unclear. In fact, in a subset of the SPACE trial (in which the application of EPD was not mandatory), there was a tendency towards a lower 30 days stroke and death rate in the non-protected (6,2 %) as in the protected (8,3 %) group. The EVA-3S study found a significantly higher rate of stroke and death following CAS than after CEA despite the application of EPD was mandatory after the first few cases performed [4]. Subsequently, in most cases EPD is probably not needed in fact it may increase the rate of complications. In our experience, the rate of embolic complications in a 50-50 % symptomatic and asymptomatic population is 1,3 %. Half of these complications (0,6 %) however occurred in>24 hrs following CAS and subsequently could not be prevented by embolic protection. We believe that the use of EPD-s should be restricted to cases with

3.1.1 Antiplatelet treatment and testing of its efficacy: Dual antiplatelet medication (Acetylsalycilyc Acid [Aspirine, ASA] and Clopidogrel ) is considered mandatory prior to any stent implantation. As the majority of these revascularization procedures are done in an elective fashion, probably the best way to apply antiaggregation is to start dual antiplatelet medication (75 mg of Clopidogrel and 100 mg of AS) 4– 5 days prior to the planned procedure. In case of emergency, the patient can be loaded with Clopidogrel using a single dose of 3–600 mg with the effect expected in 3–4 hours following oral administration. ASA can be I. Szikora National Institute of Neurosciences, Budapest, Hungary email: [email protected]

Neuroradiology (2013) 55 (Suppl 1):S15–S159 seemingly unstable plaques but with not too much arterial tortuosity that may make the navigation of the EPD complex and potentially risky. 3.2.1.2 Proximal protection, flow arrest Performing CAS under complete arrest of antegrade flow is probably very safe. The application of the Parodi device has been shown as safe and effective. Yet, due the complexity of its application this device has not achieved wide spread usage for CAS. More simple methods, however are now available, as balloon tipped guiding catheters are provided by multiple vendors for intracranial thrombectomy procedures. Performing CAS through such guiding catheters with balloon inflation and aspiration during balloon dilatation is an easy to use technique that is likely to provide acceptable safety without unnecessary technical complexity. 3.2.2 Choice of stent for CAS Properly designed stents may themselves serve as embolus protection devices if implanted without predilatation. Indeed in a subset of patients in the SPACE trial, a significant clinical benefit of using higher mesh density closed cell stents has been found, characterized by a 5,6 % event rate in the closed cell stent group versus 9,2 % in patients treated with open cell stents. Similar results were found by Bosier et al. In another study, Grünwald found a higher rate of silent T2W MRI lesions following closed cell CAS as compared with open cell, but there was no difference in the clinical outcome. Closed cell stents seem to be more effective in containing plaque material, but are less flexible, and subsequently less capable of adapting to tortuous vascular anatomy. In such cases therefore open cell stents are recommended.

S151 available balloons as of today have an over the wire design, replacing the ballon for the stent delivery system require and exchange wire. Without the exchange wire in place in case of a dissection during balloon dilatation stent delivery may not be possible resulting in permanent vessel occlusion. Having small rapid exchange balloons for intracranial purposes in the future may help in avoiding the application of an exchange maneuver. In order to avoid arterial rupture due to overdilatation, accurate measurement of the arterial diameter both proximal and distal to the stenotic section and proper sizing of balloon and stents is a must. This is best achieved by measuring sizes on 3D acquisitions. 4.1.1 Choice of stent At present, two products are available and labeled for ICS. The WINGSAN system is a self expandable device that comes preloaded in a delivery system and is supposed to be used in conjunction with a dilatation balloon (Gateway) (Stryker Neurovascular). The disadvantage of it is that it requires a two step procedure (predilatation+stent deployment) and needs an exchange manoeuver. Sizing of the balloon needs attention (to avoid overdilatation) but sizing of the stent is quite liberal due to the self expanding nature of the device. The PHAROS stent system (CODMAN, J&J) is a balloon mounted device. Navigation through tortous anatomy might be more demanding, and sizing is more critical. The stent/balloon needs to be sized according to the smaller diameter distal to the stenosis. Significant diameter difference between distal and proximal can only be compensated for by careful postdilatation using higher inflation pressure at the larger diameter section. Oversizing may easily result in vessel rupture. 4.2 Hyperperfusion syndrome

3.3 Ischemic stroke after intracranial stenting (ICS) The SAMMPRIS trial detected a 14.7 % rate of stroke [3], 60 % of those being ischemic in nature. The majority of these ischemic events (68 %) were attributed to perforator occlusions (mostly while dilating basilar artery stenosis) and only 21 % were caused by distal embolization [5]. There is no safe technique to avoid perforator occlusion. The best method is probably careful patient selection restricting ICS for those cases that have no other feasible choice. For instance, in the posterior circulation patients who are symptomatic despite good collaterals are likely to have their symptoms related to perforator occlusion to start with and have little chance of benefiting from ICS. On the contrary, those who have their presenting symptoms related to distal hypoperfusion and have no collaterals may benefit more from angioplasty. Regarding the choice of technique Submaximal Balloon Angioplasty (SBA) without stent implantation should be considered. A recent study demonstrated significantly lower event rate (4,9 %) following SBA as compared with the results of the SAMMPRIS trial. Of course in a perforator rich arterial section a submaximal dilatation should be considered when using ICS, too. An emerging option is to use SBA with drug eluting balloon in an effort of avoiding both perforator occlusion and restenosis.

Sudden increase of perfusion pressure following dilatation of severe stenosis may result in hyperperfusion of the chronically hypoperfused brain tissue. Cerebral Hyperperfusion Syndrome (CHS) occurs in 0,31,2 % of cases following CEA, may result in seizures, neurological deficit and in some cases parenchymal hemorrhage. The incidence of CHS associated with CAS has been reported at a rate of 1,1 % with a 0,6 % rate of intracerebral hemorrhage (ICH). Combining CAS and ICS the incidence was 5 % and 1,4 % respectively. Patients with preexisting ischemic lesions, severe hypoperfusion, lack of collaterals are at a higher risk of developing CHS. Subsequently, these patients must be carefully monitored postoperatively, special attention paid to keep blood pressure within the patient’s normal limits. Due to the common bradycardia and blood pressure drop following CAS, new neurological signs in the immediate postoperative period are frequently interpreted as resulting from low perfusion pressure and treated by hypertensive therapy. The possibility of CHS must be kept in mind, particularly in the high risk patient group, as in these cases hypertensive treatment has a reverse effect. References: 1.

Ringleb, P.A., et al., 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: a randomised non-inferiority trial. Lancet, 2006. 368(9543): p. 1239–47.

2.

Eckstein, H.H., et al., Results of the Stent-Protected Angioplasty versus Carotid Endarterectomy (SPACE) study to treat symptomatic stenoses at 2 years: a multinational, prospective, randomised trial. Lancet Neurol, 2008. 7(10): p. 893–902.

3.

Chimowitz, M.I., et al., Stenting versus aggressive medical therapy for intracranial arterial stenosis. N Engl J Med, 2011. 365(11): p. 993–1003.

4.

Endarterectomy vs. Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) Trial. Cerebrovasc Dis, 2004. 18(1): p. 62–5.

5.

Fiorella, D., et al., Detailed analysis of periprocedural strokes in patients undergoing intracranial stenting in Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS). Stroke, 2012. 43(10): p. 2682–8.

4 Prevention of hemorrhagic complications Bleeding might be provoked by two mechanisms: mechanical vessel wall perforation and hyperperfusion syndrome. 4.1 Vessel wall perforation Arterial perforation is a typical complication of intracranial stenting (ICS) rather than CAS. The two most common mechanisms are distal guidewire perforation and vessel rupture due to overdilatation. In the SAMMPRIS study, the rate of procedural subarachnoid hemorrhage (SAH) was 2,8 %, half of those related to wire perforation. The risk of distal wire perforation is high if an exchange maneuver is needed. With currently available techniques, this is a prerequisite of using a self expandable stent system. These require a balloon pre-dilatation. Since the

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How dangerous is revascularization? Daniel A. Rüfenacht

The human brain, a tissue representing 1- – 2 % of the bodyweight only, requires and benefits of an abundant vascular supply. Indeed, in a normal individual, around 15 % of the cardiac production is dedicated to the brain circulation, offering plenty of room for “autoregulation” and reserve for conditions, where acute or chronic supply reductions might occur. In case there is no sufficient collateral supply, within minutes of occurrence of a significant circulation reduction, there may be a breakdown of brain function in the concerned vascular territory. This is most often the case in situations, where distal embolic events occur. More proximal arterial flow reduction may lead to temporarily symptomatic brain disfunction in conditions of additional stress, such as given e.g. of arterial blood pressure drop, a situation that usually is addressed as hemodynamic insufficiency or hemodynamic stroke. Timely, i.e. before further or permanent brain damage occurs, revascularization procedures should be delivered in cases, where conventional methods are insufficient. Revascularization procedures should therefore theoretically be beneficial in all situations, where supply has been diminished significantly by vascular occlusive disease and where no collateral vascular network can compensate for lack of supply. Revascularization, as an acute or elective procedure is considered for conditions, where supply has been reduced below acceptable levels, bringing the brain vascular hemostasis at risk of imbalance. These conditions present either as an acute stroke or as a situation, where continuous decay or fluctuation of neurological or neuropsychological symptoms are associated with variable hemodynamic changes with continuous or temporary flow reduction in one or several arterial territories of the brain circulation.

D. A. Rüfenacht Neuroradiology, Swiss Neuro Institute, Klinik Hirslanden, Zürich, Switzerland email: [email protected]

Revascularization, in historical terms, has been initially surgical and became less invasive with endovascular treatment modalities. Assessment of revascularization procedure risk has remained difficult in view of a variety of reasons: First, brain perfusion assessment has remained difficult to reproduce and to quantify, and correlation to neurological or to neuropsychological deficit has unfortunately been incomplete or limited and certainly not exhaustive. Brain perfusion assessment further has focused on gray matter and omitted largely effects on white matter, what may prove to be misleading for the disease and treatment result assessment. Second, evolution and likely improvements of surgical and endovascular techniques being continuous, treatment risk assessments published may not reflect currently available technology and state-ofthe-art. Third, assessment of revascularization has to be considering outcome, i.e. impact on neurological and neuropsychological function and quality of recanalization. Whereas, both these aspects have not always been represented and considered in combination in the studies reported. All these parameters have lead to a current situation, where recanalization procedures are questioned concerning their value, risk and benefit over conventional, non-invasive treatment. This, to the dismay of many specialists involved in treating patients concerned with arterio-occlusive diseases. The presentation “How dangerous is revascularization” will provide a critical overview of the current situation, consider the literature and give you examples on the typical risks involved with revascularization procedures.

Neuroradiology (2013) 55 (Suppl 1):S15–S159

S153

Authors index (original and unedited authors list as submitted with the texts)

Abreu J. P.1.113 Abreu P. P.1.118 Abrigo J.M. P.1.116 Abu Bakar F. CO.09.08 Adams N. CO.05.05; P.1.111 Adiego B. P.1.052 Aghazadeh Y. P.1.130 Aguilar Pérez M. S.16.02; S.19.09; CO.08.05 Aguilera C. CO.03.02 Akai T. CO.05.03 Akhan G. P.1.103 Akihiko S. P.1.016 Akiyama Y. S.19.03; CO.02.02 Alcala Mata L. S.17.01 Aldaz P. P.1.003 Algin O. CO.06.06; CO.07.06 Allmendinger A. P.1.049; P.1.050 Aloni E. S.29.01 Alonso J. S.18.07 Álvarez A. P.1.052; P.1.121 Alvarez-Linera J. P.1.042; P.1.043 Alvarez-Muelas A. P.1.051 Amtage F. P.1.126 Andreu C. P.1.107 Ankenbrank M. CO.01.10 Apaydin M. CO.07.05; P.1.061; P.1.062; P.1.103 Arablinsky A. P.1.084 Arnold G. S.16.02 Arnold M. P.1.089 Arrambide G. S.18.04 Asik M. P.1.004 Ata S. CO.03.01 Auger C. S.18.04; S.18.07; P.1.034; P.1.040; P.1.119 Avarino C. P.1.100 Avsenik J. P.1.077 Ayik S.O. P. 1.103 Aymerich X. S.18.04 Ayoub D. S.15.02; S.19.01 Babaoglu O. P.1.094 Babu S. S.29.05 Baehr O. CO.03.03; CO.03.08 Baek J.H. P.1.088 Bafile M. P.1.086 Bahel A. P.1.018 Bajrovic F. CO.03.09 Baldi M. P.1.006 Banco A. P.1.125 Bankstahl J.P. CO.07.04 Bankstahl M. CO.07.04 Baptista M. P.1.060 Barkovich A.J. CO.04.02 Bargallo N. S.17.05 Bargalló N. CO.09.03 Barnaure Nachbar I. CO.03.07 Barnett Tapia C. P.1.079 Barone F. P.1.125 Barraza L. CO.08.03 Barreira J. P.1.025 Barrena C. P.1.003

Barsi P. S.18.09 Bartiromo F. CO.07.09 Bartsch A. CO.06.03 Bartusek K. P.1.005 Bastianello S. CO.06.03 Bataille J. CO.04.05 Bauer J. S.28.02 Baum T. S.28.02 Baxter B. S.16.01 Bednarczuk T. P.1.022 Bednarik J. P.1.053 Beegom Mansoor J. P.1.011; P.1.108; P.1.112 Behnke S. CO.08.07 Belanger S. CO.07.02 Bencivinni F. P.1.125 Bender B. P.1.035; P.1.039 Bendszus M. CO.05.06 Beppu T. P.1.038 Bereczki D. S.18.09 Berenstein A. P.1.020 Berkefeld J. S.15.01; CO.10.01 Bermudez S. P.1.113; P.1.128; P.1.129 Bernal B. P.1.128; P.1.129 Bert R. CO.09.07 Bettini V. CO.06.04 Bhutani I. P.1.018 Billich C. S.34.02 Bilska M. P.1.045 Binder A. S.16.06 Bink A. CO.03.04; CO.03.05 Birklein F. S.34.02 Bischof F. P.1.039 Bisdas S. S.17.07; CO.03.09; CO.05.02; CO.06.05 Biswal B. P.1.114 Black D. P.1.056 Bladowska J. CO.05.01; CO.09.06 Blanc R. P.1.072 Blasco G. S.20.03; CO.05.08; CO.05.09; P.1.009; P.1.070 Blasco J. CO.01.02 Blasel S. CO.03.08 Bocchio A. P.1.048; P.1.059 Boeckh-Behrens T. S.16.04 Boll H. S.15.05 Bonanni G. CO.10.07 Boronat Guerrero S. CO.04.04 Bose A. CO.08.03 Boskovic V. P.1.058 Bosma R. CO.10.08 Bouquigny F. P.1.115 Bourgeois A. S.20.07; S.28.03 Boyd J. S.20.07 Bozkaya H. S.15.03 Branco P. P.1.118 Brassel F. P.1.020 Braun C. S.17.07; CO.05.02 Brennan P. S.28.01; CO.05.05; P.1.019; P.1.028; P.1.029; P.1.075; P.1.111 Brennan R. S.28.01; P.1.028

Brescia Morra V. CO.09.05 Briani C. CO.10.07 Briley D. CO.08.04 Brockmann M. S.15.05; CO.01.08; CO.08.02 Brunetti A. S.18.03; CO.09.05; CO.10.07 Bryukhov V. S.18.08 Burke A. P.1.049; P.1.050 Bussiere M. CO.07.02 Bültmann E. CO.01.03; S.20.04; S.29.03 Bäzner H. S.16.02; S.19.09; CO.08.05 Börcek A. CO.06.06 Cabrera A. P.1.008; P.1.031 Cabria M. CO.04.07 Cadotte D. CO.10.08 Calli M.C. P.1.124 Cama A. CO.04.07 Camins A. CO.03.02 Campbell P. S.20.07 Campeau N. P.1.076 Campodónico D. CO.01.02 Canahuiri J. S.18.04 Candan Durak A. P.1.092 Cannizzaro F. P.1.014 Cano Granda P. CO.04.04 Cano R. P.1.121 Cantone E. CO10.07 Capurro S. CO.01.02; CO.09.03 Caranci F. S.18.03 Carceller F. P.1.051 Carlier P. CO.04.05 Carlier R. P.1.072 Carotenuto B. S.18.03 Carrasco E. P.1.003 Carrascoso J. P.1.121 Carreño M. S.17.05 Carvalho R. CO.09.04; P.1.026; P.1.027 Castellanos M. P.1.070 Castro J. P.1.128 Celik A. P.1.117 Cervantes Ibañez S. S.19.06 Cervera R. CO.09.03 Cervo A. CO.09.05 Cevasco F. P.1.030 Chai J.W. P.1.127 Chaicharoen P. P.1.015 Chakraborty S. CO.07.02 Chalissery A. P.1.075 Chan L.L. CO.09.09 Chandra R.V. S.20.06 Chang F. P.1.087 Chang F.C. S.19.07; CO.10.05 Chang H.C. P.1.036 Chang K. P.1.099 Chang S.W. P.1.069 Chankowsky J. P.1.011; P.1.108; P.1.112 Chansirikarnjana S. P.1.109 Chaovongphanit S. P.1.122 Chapot R. S.16.05; S.19.02 Charnchaowanish P. P.1.015 Charyasz E. CO.06.05; P.1.039

S154 Chaudry I. S.16.01 Chaudry Z. CO.08.03 Chawalparit O. P.1.010; P.1.015; P.1.122 Chen C. CO.08.09; P.1.102; P.1.127 Chen D.Y.T. CO.10.05 Chen W. S.18.01; CO.10.02 Chen X. CO.07.01 Chiang S. P.1.102 Chiras J. P.1.082; P.1.083 Chirife O. CO.01.02 Chiu C. CO.10.02 Chmielewski D. P.1.045 Cho S. P.1.057 Cho S.E. P.1.054 Chong A. S.20.06 Chu W. CO.02.03; CO.10.02 Chu W.F. S.19.07 Chuah K. S.20.06 Chuang T.C. P.1.036 Chung H.W. P.1.036 Chung S. P.1.102 Chung W.Y. S.19.07 Chwang W. P.1.009 Cieszanowski A. P.1.022; P.1.064 Cinar C. S.15.03 Citton V. CO.06.04; CO.10.07 Clarençon F. P.1.072; P.1.082; P.1.083 Clusmann H. CO.01.07 Cocozza S. CO.09.05 Cognard C. CO.02.06 Communale J. S.18.01 Coppola G. CO.10.07 Corboy J. CO.09.07 Corcuera-Solano I. CO.10.03 Cornelius R. P.1.018 Corral J. S.18.07 Corral J.F. CO.04.09; P.1.120 Cos M. CO.03.02 Coscojuela P. P.1.034 Costello L. P.1.075 Courtheoux P. CO.02.06 Cruz E Silva V. P.1.025 Cuberas-Borrós G. P.1.119 Cuvinciuc V. S.20.05; CO.03.07 D'Amico A. S.18.03 D'Arco F. S.18.03 D'Errico A. CO.10.07 Dabew E. S.15.01 Dabirzadeh H. CO.07.02 Danchenko I. P.1.084 Daniel M. P.1.030 Daszkiewicz P. P.1.044 Daunis-I-Estadella J. S.20.03; CO.05.08; CO.05.09; P.1.009; P.1.070 De Belder F. CO.03.06 De Belder M. CO.03.06 Debeljkovic V. P.1.058 Deike K. CO.05.06; CO.05.07 Del Carpio O'Donovan R. P.1.011; P.1.108; P.1.112 Delgado Alvarez I. CO.04.04; CO.04.08 Delgado D. CO.04.03; CO.05.04; P.1.105 Delgado I. CO.04.09; S.29.02; P.1.120 Delgado J. P.1.040 Dellani P. CO.01.03 Demerath T. P.1.047

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Desal H. CO.02.06 Deuschl G. S.16.06 Dewan M. S.16.01 Dhangana P. P.1.024 Dhangana R. P.1.024 Di Egidio V. CO.01.04; CO.01.05; CO.08.01; P.1.086 Di Maria F. P.1.082; P.1.083 Di Matteo D. P.1.100 Di Paolo N. S.18.03 Di Perri C. CO.06.03 Di Salle F. CO.06.03; CO.10.07 Ding X. CO.07.04 Dinh T. S.15.02; S.19.01 Direksunthorn T. P.1.015 Doai M. CO.05.03 Dobrynina L. P.1.110 Docema M. CO.04.03; CO.05.04; P.1.105 Dodo T. P.1.016 Dogan Baki E. P.1.068 Doh J. P.1.080 Doh Y. P.1.080 Donaire A. S.17.05 Donauer E. S.19.09 Donmez H. P.1.092 Donnerstag F. CO.01.03; S.20.04 Doorschodt T.C. CO.02.04 Dorris K. P.1.002 Doshi A. CO.10.03 Dowlut S. P.1.046 Du Mesnil De Rochemont R. S.15.01 Du T. CO.07.01 Durum Y. CO.03.01 Egger K. P.1.126 Eisele P. CO.09.02 Ektova A. S.17.03 El Sharifi S. S.19.05 El-Koussy M. P.1.093 Elefante A. CO.10.07 Elia R. P.1.030 Enriquez G. CO.04.09 Eraslan C. P.1.124 Ernemann E. S.17.07 Ernemann U. CO.05.02; CO.06.05 Ertan Y. P.1.124 Espinosa G. CO.09.03 Essig M. CO.05.08; CO.05.09; P.1.009 Estrade L. S.15.04 Fadeeva L. S.17.03; P.1.117 Fadzli F. CO.06.07 Fahrendorf D. CO.03.04; CO.03.05 Falanga G. P.1.055 Farrell M. P.1.075 Farrher E. S.17.03 Fassbender K. CO.08.07 Faulkner A. S.20.07; S.28.03 Faust S. S.34.02 Favaretto F. CO.06.04 Favaro A. CO.06.04; CO.10.07 Fehlings M. CO.10.08 Felber S. S.19.09 Felgueiras H. P.1.118 Felter A. P.1.072 Fernandes J. CO.09.04; P.1.026 Fernandez E. P.1.003 Fernandez M. P.1.120

Fernandez-Prieto A.F. P.1.051 Fiebig T. S.15.05 Figueiredo G. S.15.05 Figueras J. P.1.070 Figueroa J. S.19.08 Figueroa R. P.1.027 Filizzola C. P.1.128 Finnsson J. S.18.06 Fiorella D. S.16.01; CO.08.03 Fischer S. S.16.02; CO.08.05 Fischer U. P.1.089; P.1.093 Fladt J. CO.05.07 Fletcher G. P.1.056; P.1.101 Floca R. CO.05.06 Floca R.O. CO.05.07 Freedman M. CO.07.02 Frei D. S.16.01; CO.08.03 Frenzel H. S.29.04 Freund W. S.34.02; CO.10.04 Frohnhofen K. CO.01.08; CO.08.02 Frutos R. P.1.043 Fu J.C. P.1.127 Fu J.H. P.1.036 Fujii S. P.1.033 Fujiwara S. P.1.038 Fukami T. CO.02.01 Furdal M. CO.09.06 Furfaro D. P.1.059 Fuschi M. CO.01.04; CO.01.05; CO.08.01; P.1.086 Fushimi Y. P.1.016 Förschler A. S.17.02 Förster A. S.15.05 Gabrieli J. P.1.082; P.1.083 Gagliardo A. P.1.100 Gagliardo C. P.1.014; P.1.055; P.1.100; P.1.125 Gaido L. CO.09.07 Galvin L. P.1.029; P.1.075 Galyan T.N. CO.06.08 Garcia M. P.1.030 Garcia-Raya P.S. P.1.042; P.1.051 Garre' M.L. CO.04.07 Garzon G. P.1.042; P.1.043; P.1.051 Gash J. S.28.03 Gasiorowski J. CO.09.06 Gass A. CO.09.02 Gauthier S. S.18.01 Gauvrit J.Y. CO.02.06 Gebrim E. P.1.030 Gelal F. P.1.062 Georgievski Brkic B. P.1.037; P.1.058; P.1.074 Gerber J. S.16.03 Gersing A. CO.01.10 Ghoorah T. P.1.046 Giaimi G. P.1.100 Giesemann A. S.29.03 Gillespy M. P.1.067 Gindullis M. CO.01.08; CO.08.02 Giorgio S.M.D.A. CO.09.05 Giulioni M. CO.07.09 Glodny B. CO.01.09 Godoy L. CO.04.03; CO.05.04; P.1.105 Gómez RÍO M. P.1.012 Gonzalez R. CO.08.03 Gorozhanin A. P.1.084 Gottschalk A. S.29.05; CO.07.03

Neuroradiology (2013) 55 (Suppl 1):S15–S159 Graça J. P.1.025 Gradkowski W. CO.06.01 Graf M. CO.05.06; CO.05.07 Gralla J. S.15.01; P.1.089; P.1.093 Grams A. CO.01.09 Gratz P.P. P.1.089; P.1.093 Grauer O. CO.03.05 Grech R. P.1.029; P.1.075 Greggio N.A. CO.06.04; CO.10.07 Griebe M. CO.09.02 Grinberg F. S.17.03 Groden C. S.15.05 Gros Subias L. CO.04.08 Grunt S. CO.04.01 Guergue C. S.20.03 Guimaraes J. P.1.026 Gungor G. P.1.097 Guo W. S.19.07; CO.02.03; CO.10.02; P.1.087 Guo W.Y. CO.10.05 Gupta A. S.18.01 Gupta M. P.1.024 Gupta R. S.16.03 Gupta V. S.34.01 Gurer O. CO.03.07 Gurí X. S.18.07 Gursoy M. CO.07.05 Guzinski M. CO.05.01 Götz F. S.20.04; S.29.03 Ha T. P.1.099 Hader C. S.15.01; S.19.05 Haegy I. CO.04.05 Haktanir A. P.1.068; P.1.097 Halatsch M. CO.10.04 Haller S. S.20.05; CO.03.07 Hara Y. S.17.06 Hardt M. CO.03.03 Harter P.N. CO.03.08 Hasebe S. P.1.106 Hasiloglu Z.I. P.1.004 Hattingen E. CO.03.03; CO.03.08; CO.04.06; CO.06.02; CO.09.01 Hawk H. S.16.01 Hayoun C. P.1.052 Heck D. CO.08.03 Heddier M. S.16.05; S.19.02 Hedrich H.J. CO.07.04 Heeren M. CO.01.03 Heiland S. CO.05.06; CO.05.07 Heindel W. CO.03.04; CO.03.05 Helbok R. CO.01.09 Heldner M.R. P.1.089; P.1.093 Helle M. S.17.02 Hellinger II F. CO.08.03 Helmut R. CO.09.09 Henkes H. S.16.02; S.19.09; CO.08.05 Hennerici M.G. CO.09.02 Hennig M. CO.01.03 Herbreteau D. CO.02.06 Hermoye L. CO.06.01 Hernández D. CO.05.09 Hernandez J.T. P.1.129 Hernández L.C. P.1.121 Herrmann F. S.20.05 Hesselmann V. CO.03.04; CO.03.05 Higuchi K. CO.02.01

S155 Hirai T. S.17.06 Hirschmann M. CO.09.01 Hiruta H. P.1.017 Hj Azaman N. P.1.130 Hoepner G. CO.10.04 Hogan M. CO.07.02 Hooncharoen B. P.1.109 Hopf N. S.19.09 Hori M. P.1.017 Hortega Garcia J.L. CO.04.08 Horward-Rizea D. CO.08.05 Hoxworth J. P.1.056 Hsieh K. P.1.089; P.1.093 Hsu B. CO.02.03 Huerga E. S.18.04; P.1.040 Hung S. CO.02.03; CO.10.02 Hung S.C. S.19.07 Hur J. P.1.099 Huseynov E. P.1.004 Hwang Y. P.1.098 Ibañez M. P.1.129 Ichinose N. S.19.03; CO.02.02 Idotta C. CO.06.04; CO.10.07 Ihm E.H. P.1.088 Ihn Y. P.1.073 Iizuka H. CO.05.03 Ikizceli T. P.1.092 Iljicsov A. S.18.09 Imabayashi E. P.1.106 Imberti R. CO.06.03 Irie H. S.17.06 Itthimethin P. P.1.010 Ivaldi G.B. P.1.006 Iwata T. CO.08.06 Jablawi F. CO.01.07 Jaggi S. P.1.108; P.1.112 Jain R. CO.05.08; CO.05.09; P.1.009 Jakubcova B. P.1.053 Jancheva B. P.1.077 Jansen O. S.16.06 Januel A.C. CO.02.06 Jaramaz-Ducic T. P.1.037 Jasovic A. P.1.046 Jeibmann A. CO.03.05 Jimenez-Arribas P. P.1.107 Jin L. CO.01.01 Jirik R. P.1.005 Jito J. CO.02.01 Joe E. P.1.054 John-Baptiste A.A. P.1.079 Johnson J. S.17.08 Jones B. P.1.002 Jourdan C. P.1.072 Jung S. P.1.089; P.1.093 Jung W. P.1.073 Jurcoane A. CO.03.08; CO.04.06; CO.09.01 Jurkiewicz E. P.1.044; P.1.045 Kacar E. P.1.068; P.1.097 Kadanka JR. Z. P.1.053 Kadanka Z. P.1.053 Kadziolka K. S.15.04; CO.02.06; P.1.115 Kaelin-Lang A. CO.04.01 Kahriman G. P.1.092 Kakigi T. P.1.016 Kalashnikova L. P.1.110 Kalkan H. P.1.023; P.1.094; P.1.096

Kaller C. P.1.126 Kamide H. CO.01.01 Kaminou T. P.1.033 Kanagaki M. P.1.016 Kanasaki Y. P.1.033 Kanemaru K. P.1.106 Kang H.S. P.1.054 Kao H. P.1.102 Kao H.W. CO.08.09 Karaban' I. S.17.04 Karantanas A. S.18.05 Karasevich N. S.17.04 Karnath H.O. P.1.039 Kartal G. CO.07.06 Kartal M.G. CO.06.06 Kasakura S. CO.08.06 Katsaros V. CO.06.01 Kauczor H.U. P.1.066 Kayama T. P.1.071; P.1.123 Keil B. S.17.08 Kellner-Weldon F. P.1.093 Kerkovsky M. P.1.005; P.1.053 Kerl H.U. S.15.05 Khatri P. S.16.03 Khovrin V.V. CO.06.08 Kiefer C. P.1.093 Kieslich M. CO.06.02 Kim B.M. P.1.088 Kim D. P.1.088 Kim D.I. P.1.088 Kim E. P.1.057 Kim H. P.1.080; P.1.081 Kim S. P.1.098 Kimura H. CO.02.01 Kingstone L. CO.07.02 Kiresi D. P.1.023; P.1.094; P.1.096 Kiroglu Y. P.1.091 Kitis O. P.1.124 Kiura Y. S.19.03; CO.02.02 Kleine J. S.16.04 Klessinger S. CO.10.04 Klose U. S.17.07; CO.06.05; P.1.035; P.1.039 Klöppel S. P.1.126 Knake S. CO.06.02 Knysz B. CO.09.06 Kobayashi M. P.1.017 Kober F. S.16.04 Kocyigit A. P.1.091 Kodama T. S.29.06 Kodera J. P.1.017 Kohta E. P.1.017 Koltowska A. CO.09.06 Komoltri C. P.1.010 Kondo R. P.1.071; P.1.123 Konovalov R. CO.01.06 Konovalov R.N. P.1.090 Kooijman H. CO.03.04; CO.03.05 Korkmaz M. S.15.03 Kornienko V. S.17.03; P.1.007; P.1.117 Kotulska K. P.1.045 Kovalova I. P.1.053 Koyuncu T. P.1.097 Kozák L. S.18.09 Kozic D. P.1.074 Kreiser K. S.16.04 Kress B. S.29.05; CO.07.03; P.1.130

S156 Krings T. P.1.079 Krotenkova M. CO.01.06; S.18.08; P.1.110 Krotenkova M.V. P.1.090 Krüger M. P.1.047 Krzeski A. P.1.022 Kuczynski D. P.1.044 Kugel H. CO.03.04; CO.03.05 Kuker W. CO.08.04 Kulikova S. S.18.08 Kunert P. P.1.064 Kurisu K. S.19.03; CO.02.02 Kuroki T. P.1.017 Kurre K. CO.08.05 Kurre W. S.16.02; S.19.09 Körner H. S.15.01; CO.08.07 Köstering L. P.1.126 La Tona G. P.1.014; P.1.055 Ladino Torres M. P.1.063 Lagalla R. P.1.055 Lai P. P.1.036 Lanfermann H. CO.01.03; S.20.04; S.29.03; CO.07.04 Laothamatas J. P.1.109 Larrea J. P.1.003 Larrea Peña J. S.19.06 Laureys S. CO.06.01; CO.06.03 Law-Ye B. P.1.072 Le Jean L. P.1.082; P.1.083 Lee B. P.1.098 Lee C. CO.09.09 lee G. P.1.057 Lee G.Y. P.1.054 Lee H. CO.04.03; CO.05.04; P.1.081; P.1.105 Lee J. P.1.057; P.1.080; P.1.081; P.1.085 Lee J.W. P.1.054 Lee M.H. P.1.069 Lee S. P.1.098 Lee S.K. P.1.127 Lee Y. P.1.085 Leela N. P.1.095 Lehner B. P.1.066 Lenarz T. S.29.03 Lescher S. CO.10.01 Leung J.C.S. P.1.116 Levartovsky S. S.29.01 Lidner T. P.1.056 Lim K.S. CO.06.07 Lin B.C.J. CO.10.05 Lin C. CO.02.03; CO.10.02; P.1.087 Lin C.J. S.19.07 Lin C.P. P.1.114 Lin H.S. P.1.036 Lindig T. P.1.035 Liotta M. P.1.006 Liu T. S.18.01 Ljubisavljevic S. S.18.02 Lo Casto A. P.1.055 Looby S. CO.02.05; S.28.01; CO.05.05; P.1.019; P.1.028; P.1.029; P.1.075; P.1.111 López A. CO.01.02 Lorenzo-Bosquets C. P.1.119 Lovblad K.O. S.20.05; CO.03.07 Lubberink M. S.18.06 Lueckerath C. CO.06.02 Lum C. CO.07.02 Luna Alcala A. S.17.01

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