Pediatr Radiol (2009) 39 (Suppl 3):S508–S547 DOI 10.1007/s00247-009-1240-7
# Springer-Verlag 2009
Oral presentations Scientific Session 1: Foetal and Neuroimaging
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Fetal MRI in the evaluation of clubfoot S Servaes, A Hernandez, L Gonzalez, AF Jawad, T Victoria, A Johnson Children’s Hospital of Philadelphia (CHOP)
Prenatal diagnosis and outcome of fetuses with infantile hepatic hemangioma (IHH) Stephanie Franchi-Abella, Guillaume Gorincour, Danièle Pariente GRIIF, CHU de Bicêtre. Service de Radiopédiatrie Background IHH is the most common liver tumor in fetuses. Some are associated with severe symptoms and management remains controversial. Objective The aim of this study is to evaluate the relationship between prenatal presentation and postnatal outcome of fetuses with HIH. Materials and methods Antenatal and postnatal imaging studies, clinical and biological records of infants with antenatal diagnosis of IHH were recorded from the database of our national pediatric imaging society between 2001 and 2008. Results Sixteen fetuses had a diagnosis of IHH, 13 during the third trimester of pregnancy. The tumor was unique in 15, mean volume was 67 ml (5–240 ml). Sonographic findings showed hypoechoic, heterogeneous, well limited vascular mass with dilated hepatic artery. MRI-signal in ten patients was low on T1 and high on T2. Eight fetuses had complications with cardiomegaly (four) or cardiac failure (four). Seven of them had symptoms at birth: cardiac failure (three), pulmonary hypertension (two), consumptive coagulopathy (six), compartmental syndrome (one). All of them received symptomatic medical treatment associated with hepatic arterial or venous embolisation in three, with steroid therapy in three. Four patients died, two in the first 2 days of life without specific treatment, one after embolisation, and one after steroid therapy. One fetus received prenatal steroid therapy with in utero resolution of the cardiac failure and presented no complication at birth. Eight fetuses had no complication. Two of them became symptomatic at birth. One had a large porto-hepatic shunt complicated with pulmonary hypertension and consumptive coagulopathy and required embolisation and the other had the largest tumor associated with cardiac failure, pulmonary hypertension, consumptive coagulation and compartmental syndrome but recovered only with symptomatic treatment. Conclusion IHH remains a severe condition. Cardiac disorders, large volume and presence of large portosystemic shunt are predictive of poor perinatal tolerance. A specific management in a reference centre is then mandatory.
Background Clubfoot is often seen in the context of other pathologies that are increasingly studied prenatally with MRI, such that adequate diagnosis of this pathology may have significant repercussions. Objective The purpose of our study is to correlate fetal MRI with ultrasound in the assessment of the presence of clubfoot. Identifying how best to identify clubfoot with MRI is a secondary purpose. Materials and methods Following IRB approval and obtaining informed consent, we prospectively evaluated for the presence of fetal clubfoot in patients who were referred for MRI for a fetus with myelomeningocele. Additional sequences were obtained to evaluate the feet following the clinical MRI examination performed in a 1.5 Tesla magnet. Two experienced pediatric radiologists blinded to the ultrasound results independently reviewed the MRI for the presence of clubfoot in the fetus. The presence of clubfoot was scored for confidence of diagnosis and the results of the MRI were compared with results from the ultrasound obtained the same day. Results were compared to outcomes at birth. Results Of 23 patients enrolled in the study, one was excluded secondary to incomplete sonographic imaging. There was 100% agreement regarding the presence of clubfoot between the independent observers. The sensitivity of the MRI exam is 100% and the specificity is 87.1% using ultrasound as the standard (13 clubfeet). The plane utilized to evaluate the fetal foot was the critical component in diagnosing clubfoot rather than the sequence. Conclusion The correlation between fetal MRI with ultrasound in the evaluation of clubfoot yields a sensitivity of 100% and specificity of 87.1%. The sagittal plane provided the most useful information in the evaluation of clubfoot. 03 The role of prenatal US and fetal MRI in the assessment of VACTERL association Marianna Tagliabue, Dorothy Bulas, Rhonda Schonberg, Kenneth Rosenbaum Ospedale S Gerardo, Monza, Italy, Children National Medical Center, Washington DC, USA
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Background The diagnosis of VACTERL (vertebral, anal atresia, cardiac, tracheo-esophageal fistula, renal and limb anomalies) association prenatally can be difficult and represents a diagnosis of exclusion. Once one of these anomalies is detected prenatally, a careful and systematic analysis of the fetus is necessary to look for additional related malformations. Accurate prenatal assessment is important for appropriate counseling, management of the pregnancy, planning of the delivery and postnatal care yet US has a low sensitivity for the identification of TE fistula, anal atresia, vertebral and limb anomalies. Objective The purpose of this study is to review the role of US and MRI in the diagnosis of VACTERL association Materials and methods A retrospective review of prenatal US and/ or fetal MRI studies performed since 1998 was conducted. Prenatal studies were compared to postnatal follow up of clinically confirmed cases of VACTERL. Results Fifteen cases fulfilled the VACTERL classification criteria. Four had only a prenatal US, 11 had both prenatal US/MRI performed on the same day. Eight cases had vertebral anomalies: two diagnosed by US, one by MR. Five cases had tethered cord all missed prenatally. Eight cases had anal atresia: one identified by US due to presence of a large recto-urethral fistula, three suggested by MR. Seven had cardiac defects: four diagnosed by US none by MRI. Eight had TEF: two suggested by US due to small stomach and polyhydramnios, none by MRI. Nine had renal anomalies all detected by US and/or MR. Five had limb anomalies: two identified by US and MR, three metacarpal/digit anomalies diagnosed only postnatally. Associated anomalies identified prenatally included single umbilical artery (ten), duodenal atresia (four), lung agenesis (three), cleft lip/palate (two) and club foot (one). Conclusion Understanding the complex and, at times, subtle anomalies associated with VACTERL association allows for improved prenatal diagnosis. 04 Fetal surgery in myelomeningocele: pre and post surgical imaging (US-MRI) evaluation: case (preliminary) report F Zennaro, G Pelizzo, M Gregori, G d Ottavio, PP Guastalla IRCCS Burlo Garofolo Trieste Background The aim of myelomeningocele intrauterine repair is to improve postnatal neurologic outcome by reducing ventriculomegaly and hydrocephalus. Up to 65% of these patients shows good neurologic outcome and no hydrocephalus increasing Objective The objective of our study is to define the role of prenatal ultrasound and MRI into the evaluation of the natural history of this malformation and indication for prenatal surgical timing. Ventricular dilatation, Chiari malformation with hindbrain herniation, description and location of the spinal lesion are evaluated using both ultrasound and MRI. Preliminary results in a patient are discussed. Materials and methods US examinations has been performed using GE Voluson 730, MRI using Philips Panorama 0.6T, an open machine. First MRI evaluation has been performed at 21 weeks of gestational age, using multiplanar MRI sequences,
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mainly T2 SSH. Dynamic balance sequences have also been used. Both brain and spine have been evaluated. Ultrasound and MRI have been repeated after intrautererine surgery and postnatally in the first 3 months of life. Results Ultrasound and MRI allowed good assessment of ventricular dilatation and hindbrain herniation. In our case report MRI showed high definition of the lesion at the posterior fossa level. Ultrasound resulted to be more specific into detection of the spinal lesion. Surgery performed in utero at 23–24 weeks of gestational age avoided hindbrain herniation and postnatal shuntdependent hydrocephalus. Conclusion Fetal MRI seems to be an effective, noninvasive assessing fetal CNS anatomy. Its ability to resolve posterior fossa anatomy is superior to ultrasonography while, with respect to the evaluation of hydrocephalus and the level and nature of the spinal lesion, it may be equivalent or inferior. Both are essential for surgical timing and follow-up. 05 The virtual cranial autopsy H Martin1, D Martin1, B Tingberg2, O Flodmark1 Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweeden1, Department of Pediatric Emergency, Karolinska University Hospital, Stockholm, Sweden2 Background Post-mortem imaging has generated great interest in the literature. Available whole body CT autopsy protocols may be suboptimal for imaging of brain structures, and post-mortem CT evaluation of the head in infants is especially technically challenging. It is of great clinical importance to accurately image, describe and interpret brain findings; however, reports and guidelines available in the current literature are still limited. Requests for post-mortem advanced imaging studies are becoming progressively more common as a complement to autopsy assessment. Objective To assess image quality in our institution for optimization of imaging technique for infant post-mortem CT of the brain and to assess and quantify post-mortem brain changes in infants. Materials and methods Post-mortem CT head examinations from thirteen patients under the age of 12 months who underwent autopsy to determine cause of death during the period from 2000 to 2008 were retrospectively interpreted and compared. Clinical information was correlated. Results All CT examinations were deemed to be of adequate quality for interpretation. Of the 13 CT examinations of the brain, six (46%) had intracranial air and 12 (92%) had increased attenuation of venous sinuses. Grey white differentiation was mildly decreased in two of 13 (15%), moderately in 11 of 13 (85%), and severely in none. One case of intracranial hemorrhage was identified on the CT examinations. Conclusion Intracranial air and increased attenuation of venous sinuses are common post-mortem findings. Despite the unequivocal common endpoint of anoxia post-mortem, grey white differentiation on post mortem CT can be somewhat preserved with only a mild decrease in some cases and moderate decrease in
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most. Study results and optimization of imaging technique will be further discussed and correlated to the available literature.
06 Interest of MRI in the prenatal detection of associated brain anomalies in fetuses diagnosed with isolated uni or bilateral clubfoot Mn De Milly, N Belarbi, E Vuillard, P Souchet, Jf Oury, M Elmaleh, G Sebag Hospital Robert Debre-Paris-France Objective To determine the interest of a systematical MRI to detect associated brain anomalies in fetuses diagnosed with uni or bilateral clubfoot. Materials and methods Retrospective study of 67 cases of fetuses prenatally diagnosed with uni or bilateral clubfoot, without associated anomaly detected by the ultrasound, between 1996 and 2008. No associated anomaly was checked by ultrasound performed by a trained specialist. Brain MRI was done systematically. We differentiated fetuses with unilateral or bilateral clubfoot. The diagnosis and type of clubfoot were checked after birth. Results Significant gyration anomalies were detected by MRI, in two of the 42 cases selected after ultrasound and after postnatal checking. Both cases were bilateral clubfoot. Conclusion The interest of performing a MRI after normal ultrasound is proved. But two in 42 cases is not significant statistically. To perform a systematical MRI is a choice.
07 Assessment of the brain lesions in term neonates with TGA: magnetic resonance study Yevgeniya Yershova, Tetyana Yalynska, Andrey Maximenko, Illya Yemets Children’s Cardic Center Background TGA is congenital heart disease defined as discordant connections between the ventricles and great arteries. Due to progressive hypoxemia TGA requires correction in neonates. Preoperative stroke is likely associated with the need of balloon atrial septostomy (BAS) palliative procedure increasing arterial oxygen saturation on pre-surgery. Objective The objective was to define the BAS invasiveness degree, identify the lesions caused by this procedure and make the quantitative assessment of the lesions acuteness. Materials and methods The total of 18 term newborns with TGA, mean age 4.5 days underwent brain MRI before and after BAS (within average 3.5 days). Apparent diffusion coefficient (ADC) was calculated on both MRI in seven visually non-affected brain regions most sensitive to hypoxic–ischemic injury in neonates and additionally in detected ischemic damaged brain regions after BAS. Results None of the newborns had brain injury before BAS. The mean ADC value before BAS was: corticospinal tracts 0.97 × 103 mm2/s, basal ganglia 1.0 × 103 mm2/s, calcarine
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cortex 0.93 × 103 mm2/s, thalamus 0.9 × 103 mm2/s, frontal white matter 1.32 × 103 mm2/s, parietal white matter 1.39 × 103 mm2/s and significantly were not different after BAS. Thirteen newborns who underwent BAS had brain injury (risk difference 72.2%). White matter injury and focal strokes are the two types of lesions that often occur (53% and 18% accordingly, coexist injury 29%). ADC of the BAS caused ischemic stroke, regardless location, was low within 0.4–0.5 × 10–3 mm2/s. Conclusion We can suggest BAS has no evident influence on brain perfusion though procedure itself is invasive and can cause typical embolic ischemic brain injury revealed only with MRI at the acute stage. Early detection of the brain injury with MRI in neonates with TGA in the pre-surgery is crucial for both anesthetic and surgical strategies.
08 Efficient transcranial Doppler sonography screening in a newborn sickle cell disease cohort S Verlhac, F Bernaudin Radiology CHI Creteil France Background SCD has a prevalence of clinical stroke of 11.5% within the first 18 years of life with an incidence of a first stroke highest between the ages of 2 and 5 years (1.02 per 100 patientyears). Transcranial Doppler (TCD) can detect patients at risk for stroke and prophylactic transfusions (TP) significantly reduce the incidence of stroke. In 2004 a declining stroke rate was reported in Californian children with SCD but no report on a newborn cohort early screened with TCD has been published. Objective The aim of this study is to report the incidence of stroke in a newborn SCD cohort screened early with TCD. Materials and methods Since 1992, the Creteil newborn cohort was assessed annually with TCD from the age of 12–18 months and with MRI every 2 years after the age of five or earlier in case of abnormal TCD. Mean maximum velocities higher than 200 cm/s were considered as abnormal, resulting in initiating a PT. A switch to hydroxyurea was offered to patients with normalized velocities with TP (<170 cm/s) and normal MRA, but TP was reinitiated if velocities returned to abnormal. Patients with conditional velocities (170–199 cm/s) were assessed with TCD quarterly. Results This study included 266 (123 F, 143 M) children with SCD (217 SCA patients: 209 SS, six Sb0, two SDPunjab and 36 SC, 13 Sb+). Mean follow-up was 7.7 years, representing 2,041 patient-years. In SCA patients, abnormal TCD were seen in 45 SCA patients at a median age of 3.2 years. The KM estimate of abnormal TCD occurrence was 29.6% by the age of 18 in the SCA population. No stroke occurred in the SC/Sb+ population whereas three strokes occurred in the SCA patients. The rate of stroke was 0.15 per 100 patient-years in overall population, 0.19 per 100 patient-years in SS/SB0 patients. The KM estimate of stroke risk was 1.9% by the age of 18 years in SCA. At the age of 8 years the prevalence of ischemic lesions in patients without history of stroke was 28 of 129 SCA patients (21.7%). MRA was abnormal in 16 of 45 children with abnormal TCD.
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Conclusion We report that early screening of children with sickle cell disease by TCD and transfusions effectively prevent stroke in a newborn cohort stroke, reducing the risk for stroke at 18 years from 11% to less than 2%.
09 Sonologists vary in their use of diagnostic labels for white matter lesions seen on cranial scans of severely premature infants: the Elgan Study SJ Westra, K Kuban, A Leviton Massachusetts General Hospital, Boston, USA Background Prior studies have shown marked operator variability in the diagnosis of white matter lesions on cranial ultrasound scans. Objective To study how diagnostic labels are applied to white matter disease seen on cranial ultrasound scans of Extreme Low Gestational Age Neonates (ELGANs) Materials and methods In 1,452 ELGANs, routine cranial ultrasound scans were obtained in the first, second postnatal weeks and between the third postnatal week and term. All scans were read independently by two sonologists. We reviewed the use of 4 diagnostic labels, early periventricular leucomalacia (E-PVL), cystic C-PVL, periventricular hemorrhagic infarction (PVHI) and other white matter diagnosis (O-WMD) by 16 sonologists at our 14 study institutions. We evaluated the association of these four labels with the location and laterality of identified hyperechoic and hypoechoic lesions, location and severity of intraventricular hemorrhage (IVH), and characteristics of ventricular enlargement. Results Sonologists differed substantially in their tendency to use the diagnostic labels. Three readers applied the label E-PVL to more than one fourth of all the scans they read, while eight applied the label to ≤5% of scans. Similarly, five applied the label PVHI to ≥10% of scans while three applied this label to ≤5%. Overall, five readers identified white matter lesions in ≤20% of the sets of scans, whereas 4four others did so in ≥48%. More than one third of scans given a diagnosis of C-PVL had unilateral hypoechoic lesions. Significantly more IVH was seen in PVHI than in any of the other categories. White matter lesions in PVHI were more extensive than in PVL, and were more anteriorly located. Hypoechoic lesions on late scans were in the same locations, regardless of the label applied. Conclusion Experienced sonologists differ considerably in their tendency to apply diagnostic labels. This variability is due to a lack of universally agreed-upon definitions.
010 Imaging appearances of X-linked hydrocephalus David Lee, Eric Faerber, Joseph Piatt St.Christopher’s Hospital For Children Philadelphia, USA Background X-linked hydrocephalus is a form of autosomal recessive congenital hydrocephalus with a characteristic set of imaging criteria, with a paucity of reports in the radiologic
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literature. We report two cases of X-linked hydrocephalus occurring in half-brothers who presented together at our institution. The characteristic clinical and imaging features of this rare disorder are described. Objective Description of the clinical and imaging features unique to this disorder. Materials and methods Two male patients, aged 5 and 16 years, presented to our institution, each with a history of hydrocephalus with ventriculoperitoneal shunt placement and severe mental retardation in the setting of MASA syndrome (mental retardation, aphasia, shuffling gait, and adducted thumbs). The patients were half-brothers, with the same mother and different fathers, consistent with the X-linked inheritance pattern of MASA. Head CT scans of both brothers were performed, and a non-contrast brain MRI of the 16-year-old patient was also performed. Results Imaging features included persistent enlargement of the lateral ventricles, which also showed an unusual, lobulated or “rippled” peripheral contour. There was also separation of the frontal horns of the lateral ventricles, in a pattern consistent with agenesis of the corpus callosum, and vermian hypoplasia. Both patients presented with MASA syndrome. Conclusion X-linked hydrocephalus is a relatively uncommon cause of congenital hydrocephalus which has a characteristic set of imaging criteria on both CT and MRI, including cerebellar vermian hypoplasia or agenesis, enlargement of the massa intermedia, and dilatation of the lateral ventricles with a rippled ventricular wall pattern following shunt placement. Neuroimaging is an important part of the workup of this rare disorder.
011 Fiber tracking of molar tooth sign Laura Merlini, Joel Fluss, Benedict Rillet, Magalie Viallon, Maria Isabel Vargas, Sylviane Hanquinet University Hospital of Geneva Background Ocular motor apraxia is one of the cardinal signs of Joubert syndrome and Joubert syndrome related disorders (JSRDs): moreover, molar tooth sign (MTS), the neuroimaging hallmark of JS and JSRDs, is seldom found in congenital oculomotor apraxia (COMA), rising the question if COMA can be considered as part of JSRDs. Genetics of this field has tremendously improved but the nosological definition of JSRDs remains problematical and, at present, a mutation is detectable in only about 40% of patients. MRI fiber tracking (FT) studies described absence of decussation of the superior cerebellar peduncles (SCP) in JS. No reports exist in the literature so far on FT findings in JSRDs or in COMA. Objective We investigated FT pattern of SCP in COMA and JSRD in order to go further in the comprehension of the developmental mechanisms of diseases sharing some clinical and neuroimaging signs. Materials and methods Three children with clinical COMA and two with JSRD underwent MR imaging with a 1.5 T MRI-unit. Conventional brain MR imaging protocol, including T2-
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weighted fast-spin echo, 3D T1-weighted echo-gradient and FLAIR, was followed by DTI. Isotropic diffusion-weighted images, apparent diffusion coefficient maps and color-coded fractional anisotropy maps, including FT, were subsequently calculated. Results In all five cases conventional MR imaging showed MTS. In the three patients with COMA, DTI and FT showed normal decussation of the SCP while in both cases with JSRD no decussation of these structures was present. Conclusion JSRDs decussation patterns of SCP is abnormal like in JS, while the latter is normal in COMA. The debate if COMA should or should not be integrated in the group of JSRD still remains open.
Scientific Session 2: Gastrointestinal System 012 Nasogastric tubes and videofluoroscopic swallowing studies Mutaz Alnassar, Kamaldine Oudjhane, Jorge Davila The Hospital for Sick Children, Toronto, Canada Background Videofluoroscopic swallowing studies (VFSS) are considered to be the gold standard method for assessing the risk of aspiration. Not infrequently, infants and children with feeding difficulties who undergo VFSS will have nasogastric tube (NGT) in place. Objective To investigate how reliable VFSS are in assessing the risk of aspiration with an NGT in place. Materials and methods This is a retrospective review of VFSS performed at our institution in 6.5-year period including only patients with their studies done with and without NGT. One hundred twenty-five studies (51 with NGT and 74 without NGT) are compiled in 46 patients (30 males and 16 females) with a mean age 5.5 months (1 month–7 years). All patients had underlying medical conditions that might impair the swallowing mechanisms; genetic syndromes, post cardiac and tracheoesophageal fistula surgery were among the commonest. The VFSS check list includes: weak sucking, incoordination, nasopharyngeal reflux (NPR), pooling, penetration, aspiration and associated cough or respiratory compromise. Occurrence rates of these events in studies done with and without NGT are compared. Results Nine patients had aspiration in both studies done with and without NGT, 17 had aspiration only with NGT and eight without NGT (p-value=0.09). No significant differences were seen in the occurrence of cough or respiratory compromise between both groups (p-values of 0.39 and 0.15 respectively). No statistical differences were noted regarding incoordination, pooling, NPR, penetration or weak sucking (p-values of 0.27, 0.28, 0.49, 0.67 and 0.69 respectively). Conclusion No significant statistical differences are found in the occurrence rate of the different events checked in VFSS done with and without NGT. The presence of NGT does not alter the results of VFSS and does not increase the risk of aspiration.
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013 Necrotizing enterocolitis: optimal radiographic view(s) for diagnosis and follow-up J Fogel, M Reed, M Seshia Departments of Radiology, Pediatrics and Child Health, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada Background The purpose of this study was to develop a guideline for obtaining abdominal radiographs in infants with suspected or proven necrotizing enterocolitis (NEC). Objective To determine the optimal radiographic view(s) and duration of follow-up imaging for evaluating these patients. Materials and methods A retrospective, 8-year review of abdominal radiographs obtained from infants with suspected or proven NEC admitted to a tertiary care neonatal intensive care unit was undertaken. Radiographs were randomized and blinded to patient name, date of birth, hospital identification number, and date of acquisition. Each radiograph was reviewed over a 1month period by a senior pediatric radiologist and scored for the presence, absence, or suspicion of intramural gas (IMG), portal venous gas (PVG), and pneumoperitoneum. Results Six hundred and ninety radiographs from 60 patients were reviewed. IMG was present in 33 patients, PVG in eight, and pneumoperitoneum in 12. In 205 pairs of supine anteroposterior and left-lateral decubitus (LLD) radiographs matched by time of study, IMG was seen unequivocally on nine supine radiographs, and on five LLD radiographs. Pneumoperitoneum was identified ten times on LLD radiographs. Only four corresponding supine radiographs were concordant. There was no significant difference for the detection of PVG. IMG first appeared in 21 patients (64%) within 2 days of initial clinical suspicion. PVG, if present, was seen on the same day in six (75%). In eight infants (67%), bowel perforation occurred within 2 days. Conclusion IMG is more confidently diagnosed on supine radiographs, as is pneumoperitoneum on LLD radiographs. In infants with suspected NEC, routine follow-up abdominal radiography may be discontinued after 2–3 days if clinical signs are stable. 014 Eosinophilic esophagitis: fluoroscopic findings with endoscopic and pathologic correlation Emily Lorenz, Larry Binkovitz, Carlos DiLorenzo, Samir Kawash Nationwide Children’s Hospital Background Eosinophilic esophagitis (EE) is an increasingly common disorder diagnosed in children with dysphagia, pain, vomiting, and/or food impaction. However, EE has received little attention in the pediatric radiology literature. Objective To describe the fluoroscopy findings of EE and assess its usefulness in diagnosis and management. Materials and methods With IRB approval, the clinical, endoscopic and fluoroscopic findings of the 17 patients with biopsyproven EE (eosinophils >15/hpf) evaluated between 2000 and 2008 were retrospectively reviewed.
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Results Patients presented with impaction (n=5), dysphagia (n=9), pain (n=4), or other (n=12). We found coexisting allergy in (n=11/ 17), asthma (n=4/17) and/or eosinophilia (n=3/4). EE was present in the proximal (n=1), mid (n=4) and distal esophagus (n=6), and at the GE junction (n=1); eight had multiple sites of EE. The location of EE was not specified in 11 patients. Eosinophilic infiltration averaged 60/hpf. Endoscopy revealed esophageal furrowing (n=15), stricture (n=5), white plaques (n=9) or mucosal abnormalities (n=9). Endoscopy was normal in three patients. Esophagram findings include stricture (n=5), impaction (n=5), mucosal abnormality (n=1) or was normal (n=17). UGI was normal in 14 of 20 patients with abnormal endoscopic findings. Esophagram revealed obstructing foreign body in all five patients with proven impaction. After removal of the foreign body impaction, follow-up esophagrams were normal (n=3). Conclusion Strictures were not found in patients presenting with food impaction suggesting dysmotility rather than esophageal narrowing may have caused the impaction. Strictures demonstrated with esophagram were never confirmed with endoscopy. It can be seen from this study that although UGI procedures can accurately identify impaction in EE patients, endoscopy with biopsy are required to fully evaluate and manage children with EE. 015 Use of sonography in the evaluation of the cervical and thoracic esophagus in children F Bakirtas Palabiyik, S Bayramoglu, N Turan Guler, S Daglar, T Cimilli Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Radiology Department, Istanbul Background Sonography has been used widely in children for the evaluation of the abdominal esophagus while the cervical and thoracic esophagus have seldom been studied. Objective The aim of this study was to determine the normal sonographic appearance and to provide measurements of the cervical and thoracic esophagus in healthy children. Materials and methods In this prospective study 93 children (51 girls and 42 boys) aged 1–12 years were examined sonographically. With the patients in a supine position for evaluation of the cervical esophagus, turned their heads to the right and probe was placed on the left side of the trachea and next for thoracic esophagus with their hands raised over their heads transducer was placed along the left side of the sternum. The length of the cervical and thoracic esophagus was measured in the longitudinal and both the anteroposterior and transverse diameters were measured in the transverse scan as was the thickness of the cervical esophageal wall. Results The cervical esophagus was identified in all of the children while in 41 (%44) of the 93 subjects the thoracic esophagus could be demonstrated by sonography. The mean length of the cervical and thoracic esophagus was measured respectively 33 and 92 mm in 1–5 years, 39 and 99 mm in 5–10 years and 45 and 112 mm in 10–15 years. Anteroposterior and transverse diameters of cervical and thoracic esophagus was increased with age. The mean thickness of the cervical esophagus was 2.8 mm in all ages. The
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cervical esophageal wall appeared as five layers on sonograms and lumen was evaluated clearly. Conclusion Evaluation of the cervical esophagus is readily achievable with sonography in children while visualization of the thoracic esophagus could be difficult because of the structures deep location and the influences of bones and gas in the lungs. 016 Estimation of effective dose for fluoroscopic pneumatic intussusception reduction in modern practice J Kapur, OM Navarro, F Bin-Hussain, K Thomas, A Daneman The Hospital for Sick Children, Toronto, Canada Background Fluoroscopic pneumatic intussusception reduction (FPIR) is a widely practiced and effective method of intussusception management in children which obviates surgery in the majority of patients. Small risks include the potential risks associated with ionizing radiation. There is limited data available regarding effective dose (ED) during FPIR. Objective To estimate the ED associated with FPIR at a large pediatric teaching hospital. Materials and methods Retrospective review of dose records of all FPIR attempts in 18-month period. Patient age, fluoroscopy time (FT), dose area product (DAP), and clinical outcome were recorded. If more than one reduction attempt was made per intussusception episode, dose parameters from each attempt were summated. ED estimates were derived using DAP and age-specific conversion factors (NRPB-R279). Results One hundred four intussusception episodes involving 117 reduction attempts occurred in 90 patients. Mean FT per episode for the whole cohort was 3.8 min (range 0.3–24), mean DAP=0.67 Gycm2 (range 0.04–6.5) and mean ED=0.7 mSv (range 0.05–3.8). Mean ED decreased with increased age [1.3 mSv (0–6 months), 0.7 (7– 30 months), 0.4 (31–90 months)]. Unsuccessful FPIR episodes were associated with higher mean ED and FT (1.6 mSv and 9.5 min) compared to successful FPIR (0.51 mSv and 2.6 min). Conclusion With modern fluoroscopic equipment the mean ED of FPIR is low, equivalent to <3 months background radiation and significantly less than that associated with pediatric head CT. Advances in fluoroscopic technology, particularly pulsed fluoroscopy, have resulted in considerable dose reduction compared to previous reports. Although one cannot dictate a cutoff of FT in any particular case, every attempt to decrease FT must be made. It behooves all radiologists who perform FPIR to review their FPIR practices at their institutions particularly FT and ED calculations. 017 Abdominal lymphadenopathy in children with tuberculosis presenting with respiratory symptoms Shaun Scheepers, Savvas Andronikou, Ayanda Mapukata, Peter Donald University of Stellenbosch
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Background The radiological hallmark of primary pulmonary tuberculosis in children is thoracic lymphadenopathy. Chest radiography continues to be a first-line radiological investigation. Ultrasonography is a sensitive tool for the detection of abdominal lymphadenopathy and may have an important role in the investigation of tuberculosis in children, because of its availability, affordability and avoidance of ionizing radiation. Objective To determine the prevalence of abdominal lymphadenopathy in paediatric patients with confirmed tuberculosis, presenting with respiratory symptoms. Materials and methods Chest radiographs and abdominal ultrasounds of 47 children with confirmed tuberculosis and respiratory symptoms were reviewed. The prevalence of abdominal tuberculosis was determined on ultrasound and comparisons were made between thoracic and abdominal lymphadenopathy, to determine the relative effectiveness of ultrasound. Results On ultrasound, the prevalence of abdominal lymphadenopathy was 19%. Radiological evidence of abdominal TB was found in 23% of patients. 89% of patients had evidence of pulmonary TB on chest radiography, with 70% of children having thoracic lymphadenopathy. If chest radiography were considered the radiological reference standard, abdominal ultrasonography had a sensitivity of 18% and a specificity of 79% for thoracic lymphadenopathy, with an overall accuracy of 32%. Conclusion Since these patients were selected on the basis of having respiratory TB, the fact that 23% had abdominal TB on ultrasound is clinically significant. An association exists between abdominal and thoracic lymphadenopathy, however, due to its poor sensitivity and accuracy, abdominal ultrasound cannot be used alone for the prediction of thoracic lymphadenopathy. Ultrasound may therefore be a useful supplementary tool for the primary investigation of TB in children, due to its safety, portability and affordability. 018 Clinical predictors of a diagnostically accurate ultrasound in children with suspected appendicitis Carina Man*, Suzanne Schuh*, Arun Mohanta*, Amanda Murphy*, Rahim Moineddin**, Andrea S Doria* et al * The Hospital for Sick Children, Toronto, Canada, ** University of Toronto, Canada Background Ultrasound (US) has emerged as the primary imaging modality on the diagnosis of acute appendicitis. Objective To determine clinical predictors (CP) associated with a high probability of an accurate US in children with suspected appendicitis, using histologic results or clinical follow-up as reference standards. Materials and methods Children (age range, 4–17 years, median, 10) who presented to the Emergency Department (ED) with suspected appendicitis and had clinical indication for an abdominal US were prospectively enrolled. CP were: age, gender, body mass index, duration of abdominal pain, white blood cell count (WBC), pain in the right lower quadrant upon palpation [faces pain scale-revised (FPS-R)] and clinical probability of appendicitis (CPA). Images were
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classified as positive, negative or equivocal for appendicitis. A multivariable logistic regression analysis was used to identify the relationship between the accuracy of US results and CP. Results Two hundred sixty-five patients [female, n=126 (48%); male, n=139 (52%)] participated in the study. Using backward, forward and stepwise selection techniques, the predictor that best indicated the accuracy of US results was FPS-R. When independently evaluated, the odds ratios of gender (male vs female, 2.7), WBC (1.13) and CPA (1.04) indicated that these predictors significantly increase the odds of the outcome (accurate diagnosis of appendicitis). Overall, one fourth of patients who had a second imaging examination did have a final diagnosis of appendicitis [28% (11/40) for a second US scan and 23% (7/31) for a subsequent CT examination]. Considering equivocal US results as negative or positive results (sensitivity analysis), respectively, the sensitivity of US ranged between 85% and 99% (95% CIs, 0.76–0.99). Conclusion FPS-R, male gender, WBC and CPA are associated with an accurate diagnosis of appendicitis, and could be used as screening tools for tailoring patients to further US examination. 019 The value of ultrasound in differential diagnosis between neonatal obstructive hepatitis and congenital biliary atresia Yinzi Su, Xinyu Yuan, Yulin Zhang Capital Institute of Pediatrics, China Background It is an challenge to pediatric radiologists to differentiate congenital biliary atresia and neonatal obstructive hepatitis correctly. Objective To evaluate the value of ultrasound in differential diagnosis between neonatal obstructive hepatitis and congenital biliary atresia. Materials and methods Ultrasound data of 19 cases with neonatal obstructive hepatitis and 21 cases with congenital biliary atresia were reviewed retrospectively, and focused on the gall bladder shape and size, gall bladder contraction and the visualization of the triangular cord sign. Results Statistically, the gall bladder size of patients suffered from neonatal obstructive hepatitis was significantly greater than that of patients with congenital biliary atresia (P<0.05). The presenting rates of gall bladder contraction and the triangular cord sign in the two groups were significantly different (P<0.05). Conclusion The size and shape of gall bladder, triangular cord sign and the ability of gall bladder contraction were useful sonographically in differential diagnosis between neonatal obstructive hepatitis and congenital biliary atresia. 020 Colon agenesis beyond the cecum-additional plain image findings Alan E Oestreich Cincinnati Children’s Hospital Medical Center Background The congenital entity of colon agenesis beyond the cecum occurs in as many as one in 40 cases of imperforate anus.
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Classically, such infants present on plain radiographs with a bowel loop containing gas that extends over 50% of the abdominal width. Objective To present additional plain image findings, the abnormally wide and the abnormally narrow pubic symphysis. To discuss the value of ultrasound in supporting the diagnosis. Materials and methods Personal cases (including a 1974 case of the Season in Seminars in Roentgenology), cases provided by several pediatric radiology colleagues, and other cases in the literature are reviewed. Results Colon agenesis beyond the cecum (also known as “basketball colon”) is a complex gastrointestinal, urinary, and skeletal malformation. In all cases reviewed, a fistula, usually patent, extends from the dilated “cecum” loop to a bladder or the site of expected bladder. In some cases, the bladder has been duplicated side-by-side, and in that event the pubic symphysis has been wide. In our proband, no bladder was present and the pubic symphysis and bony pelvis were narrow. Ultrasound can evaluate the bladder status with ease and may show the fistula; kidneys should be examined as well. Also, we have encountered 1 patient with imperforate anus and a bowel loop over 50% of abdominal width associated with a different set of malformations than complete agenesis of the colon beyond the cecum. Conclusion Prompt cecostomy or ileostomy is required in the subset of imperforate anus with this condition. The abnormally wide or the abnormally narrow pubic symphysis can assist in suggesting the diagnosis and pointing to the associated bladder malformation.
Scientific Session 3: Chest
021 Optimising reference mAs in CT chest imaging Carolyn Young, Andrew Taylor, Catherine Owens Great Ormond Street Hospital for Children NHS Trust Objective To understand the relationship of reference mAs on image quality and effective dose and the need to alter the reference mAs for different patient age groups. Materials and methods In three weight groups <15, 15–35 and >35 kg, comparison of effective dose and image noise was made between 20 initial patients scanned at 100 kVp at 70/70/120 mAs and 54 subsequent patients at 35/50/70 mAs. Images reconstructed at 1 and 5 mm slice on soft tissue (B30) and 1 mm sharp (B60) algorithm. Results The scanner automatically adjusts the effective mAs to the given noise level as set by the reference mAs. At 70/120 reference mAs the image noise was 18±3 HU and 9±2 at 1 and 5 mm slices on B30, with effective dose of 2.9±0.7/3.1±0.3/5.3±0.3 mSv for the three weight groups. At current settings, noise was 23 HU±2.8 and 12 HU±1.5, with dose of 1.2±0.3/2.3±0.5/3.9±1.1 mSv respectively for 35/50/70 mAs. Student’s t test p-values between the two groups for dose were 0.0007/0.0005/0.0008, for the three weights, and the p-values for all the noise data at both 1 and 5 mm were <0.001. At sharp algorithm (B60) measured in lung parenchyma noise varied between 133-110HU, this may be explained by limited breathholding capability in younger children with lung pathology.
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Conclusion The recommended use of single reference mAs value to cover wide weight range leads to higher radiation exposure in patient of lower weight. Optimising image noise and adjusting the reference mAs to reflect the patient size resulted in a 50% dose reduction for younger patients but with an increase in image noise that was acceptable and maintained diagnostic image quality. 022 Relationship of reference mAs and image quality in CT chest imaging Carolyn Young, Alistair Calder, Andrew Taylor, Catherine Owens Great Ormond Street Hospital for Children NHS Trust Objective To determine image noise levels at different reference mAs and kVp settings. Materials and methods A phantom (equivalent size to a 6 year old) was scanned between 20–120 reference mAs in 10 mAs steps at 80/100/120 kVp. Images reconstructed at 1 and 5 mm thickness on soft tissue (B30) and sharp (B60) algorithms on all settings. Image noise, contrast and effective dose were assessed compared at all 3 kVp settings. Results Good data correlation between phantom and patient data at 100 kVp 50 mAs with image noise of 10 and 20 HU at 5 and 1 mm B30 slices and 118 HU at B60. Effective dose was 2.9 mSv female and 2.5 mSv male, breast dose equivalent 7.6 mGy. Achieving the same noise level at 80 kVp requires increase to 80 mAs with dose 2.1 mSv female, 1.8 mSv male, and 5.5 mGy breast dose. Similarly 120 kVp requires a decrease to 30 mAs with dose 2.7 mSv female, 2.4 mSv male, breast dose 7.2 mGy. Mean contrast level was 651/490/394HU and contrast to noise ratio was 42/44/37 for 80/100/120 kVp respectively. Conclusion Reducing kVp from 100 to 80 with increase in reference mAs resulted in 28% dose reduction with image quality maintained and improved contrast resolution. Image noise should be optimised to allow informed decision making on appropriate scanning parameters with patient benefit. 023 A specially prepared natural sponge as a reliable, realistic and inexpensive lung phantom for image quality studies in computer tomography (CT) Claus-Peter Wallner, Karl Schneider, Ullrich Mueller-Lisse, Murry Kohn, Maximilian Reiser Institute for Clinical Radiology, University of Munich Background Within an Europe-wide CT study different lung phantoms were tested to evaluate image quality of different CT protocols and CT scanners. Phantoms with inflated native lung resections, phantoms of different sized tube convolutes and a specially prepared natural sponge were used. Objective To develop and evaluate a realistic phantom for reliable and reproducible image quality comparison of different CT scanners and different high resolution CT (HRCT) protocols of the lung.
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Materials and methods Phantoms with inflated native lung resections were not stable for prolonged measurement studies and their results were only partly reproducible. Phantoms of different sized tube convolutes showed reproducible results but were with respect to realistic lung structures too artificial. Alternatively, we evaluated a natural sponge saturated with different concentrations of iodinated contrast media on different CT scanners using different protocols for both the sponge alone (lung model) as well as for a sponge inserted in a corpse of a chicken (infant thorax model). Results A lung equivalent density of the sponge saturated with iodinated contrast media was reached with a 50% Solutrast® 300 solution. Six defined structures of an exemplary slice with 1 and 3 mm slice thickness were rated twice on a three point scale by three radiologists. There was a good inter- and intra-rater correlation for both phantoms (lung/infant thorax: r=0.87/0.89, respectively). There was also no significant inter-scanner variation for the five different computer tomographs [three different manufacturers; 1, 64 (n=3) and 128-row] with respect to the reproducibility for both phantom variants. Conclusion The sponge phantom is a reliable, realistic, modifiable as well as a simply and inexpensively to produce phantom for image quality studies in CT of the lung. 024 Congenital multilobar emphysema, a characteristic lung growth disorder attributable to filamin a gene mutations Peter A Taylor, Megan K Dishop, Timothy E Lotze, George B Mallory, R Paul Guillerman Phoebe Putney Memorial Hospital, Texas Childrens Hospital Background Filamin A (FLNA) is an X-linked gene encoding an actin-binding cytoskeletal protein involved in neuronal migration, cardiovascular development and connective tissue integrity. FLNA mutations have been previously associated with periventricular nodular heterotopia, cardiovascular anomalies, and Ehlers–Danlos variants, but pulmonary growth disorders have not been previously reported. Objective To report the association of FLNA mutations with congenital multilobar emphysema. Materials and methods A retrospective review was conducted of the imaging exams and clinical charts of two full-term infants with FLNA mutations, periventricular nodular heterotopia, and a pathologic diagnosis of a lung growth disorder Results CXR and Chest CT exams obtained during infancy in both patients with FLNA mutations revealed severe multilobar hyperinflation with hyperlucent lung parenchyma, attenuation of peripheral pulmonary vessels, pulmonary architectural distortion, atelectasis, and central pulmonary artery enlargement. Expiratory CT imaging and V/Q scintigraphy were obtained in one patient, revealing air trapping and matched ventilation–perfusion defects. Bronchoscopy showed normal anatomy of the central airways in both patients. Multilobar emphysema was noted on surgical and gross pathological inspection, and simplified enlarged alveolar air spaces and pulmonary hypertensive changes were noted on histopathologic exam. Both patients with FLNA mutations developed severe progressive respiratory failure requiring lung transplantation.
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Conclusion In addition to periventricular nodular heterotopia and cardiovascular anomalies, FLNA mutations are associated with a lung growth disorder characterized by simplified enlarged alveolar air spaces with severe hyperinflation, resulting in the imaging appearance of congenital multilobar emphysema and the development of progressive respiratory failure. These findings imply an important role of the filamin A actin-binding protein in alveolar modeling during lung growth. 025 The chest imaging of acute respiratory distress syndrome (ARDS) caused by pulmonary disease in children Xinyu Yuan, Surong Li, Wenliang Yu Capital Institute of Pediatrics Background To know the imaging feature of early stage of ARDS in Children is useful to management. Objective To analysis the imaging of chest X-ray and CT in ARDSp in children. Materials and methods Fifty-four cases of ARDS due to pulmonary diseases were involved in the study, including 31 male and 23 female, age ranged from 29 days to 14 years old (mean age was 4.1 years). All patients underwent bedside chest radiography (CT scan was performed within 12 hours of the chest film on four cases). The primary and secondary pulmonary signs were evaluated. Results In study group: 50 patients (92.6%) were pneumonia, the other reasons account for 7.4%. Consolidation (61.1%), white lung (31.5%) and ground-glass opacification (7.4%) were the primary signs. The secondary signs included overinflation (13 cases), atelectasis (three cases), pneumomediastinum (three cases) and pneumothorax (one case). Thirty-seven cases in the non-leukocythemia group, consolidation type accounted for 70.3%; 13 cases in the leukocythemia group, white lung accounted for 53.8%. The difference of different type in the two groups was significant statistically (χ2 =10.72, P=0.005). In CT of four cases, consolidation and ground-glass opacification could be seen too. Consolidation tended to be dorsal and ground-glass opacification tended to be ventral. Conclusion The primary pulmonary risk factor for the acute respiratory distress syndrome in children was pneumonia. The major features of chest X-ray were consolidation and white lung. Consolidation was the chief sign in the non-leukocythemia group, whatever white lung was the chair sign in the leukocythemia group. CT scan maybe provided more specific and detail information on the type and distribution of pathological changes. 026 An examination of the association between HRCT findings and pulmonary function in children with CTD associated diffuse lung disease James Carmichel, Karen Rosendahl, Clarissa Pilkington, Paul Aurora, Catherine M Owens, Kiran Nistala, Emma Scase Great Ormond St.Hospital
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Background HRCT is a sensitive method for detecting early diffuse lung disease, however reports on the association of these findings to measures of lung function in children with connective tissue diseases (CTDs) are sparse. Objective To examine the association between HRCT findings and pulmonary function in children with CTD associated diffuse lung disease. Materials and methods HRCT and pulmonary function tests were performed in 14 children (ten females) with connective tissue diseases, including juvenile dermatomyositis, juvenile idiopathic arthritis and systemic vasculitis. Mean age at examination was 12 years (range 5– 15 years). HRCT examinations were performed within a median of 28 days (range 0–159) of the lung function tests, including lung clearance index (LCI) and spirometry (FVC, TLCO, FEV1-Z, MEF25z). All HRCT scans were scored by three radiologists (consensus) blinded to clinical data, using a combined Hansell–Brody score. Each pulmonary lobe was scored for the presence and severity of the following features: reticular and ground glass opacities, vasculitis, bronchiectasies, bronchial wall thickening, mucus plugging and mosaicism/airtrapping, giving a potential maximum score of 259. Results Abnormalities of the lung parenchyma were demonstrated in all of the 14 children, peripheral reticular change being the dominant pattern (92%). There was statistically significant association between total HRCT score with severity of lung function abnormalities as assessed by MEF25-z (Spearman’s ρ= −0.6, p=0.027) No other associations were demonstrated. Conclusion HRCT findings in children with diffuse lung disease closely associate with abnormal lung function as measured by reduced MEF25-z. 027 Radiological changes post lymph node enucleation for airway obstruction in children with pulmonary TB AT Maydell 1, P Goussard1, S Andronikou2, F Bezuidenhout1, C Ackermann1, RP Gie1 1. University of Stellenbosch, Tygerberg Hospital, Cape Town, South Africa 2. University of Cape Town, South Africa Background Tuberculous lymphadenopathy causing airway obstruction in children may be life-threatening and require surgical enucleation of the lymph glands. There are no studies investigating the radiological picture post surgical enucleation of TB lymphadenopathy in the chest. Objective To determine whether there are radiological correlates to resolution of airway stenosis and its complications post lymph node enucleation in paediatric PTB. Materials and methods A retrospective study of the imaging in 21 paediatric cases having undergone TB lymph node enucleation. Results Bronchus intermedius stenosis was present in 95% of patients undergoing enucleation, followed by left main bronchus (81%) and right main bronchus (67%) stenosis. Right lung collapse/consolidation occurred more frequently (48% to 62%) than left lung collapse/consolidation (10% to 14%). Resolution of bronchus intermedius stenosis and right lower lobe collapse/
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consolidation is the most consistent postoperative finding. Nine children resolved at an average time of 6.5 months postoperatively, while ten children were still resolving at an average time of 4.5 months. Conclusion The resolution of the complications of lymph node enlargement (i.e. airway stenosis and lung collapse/consolidation) was seen more frequently than the resolution of the offending lymphadenopathy itself. Right sided disease was necessary to produce complications severe enough to require enucleation. Subcarinal lymph node enucleation is sufficient for resolution of left main bronchus stenosis and associated left lung sequelae. 028 Radiographic manifestations of primary tuberculosis in childhood: the value of serial radiographs in latent and active pulmonary TB R Singaroyan, T Win, A Raghavan Sheffield Children’s Hospital Background The incidence of tuberculosis is increasing in the UK and in developed countries. The diagnosis of primary pulmonary tuberculosis is often difficult due to ambiguous clinical presentation, the paucity of chest radiographic changes and negative sputum/ gastric lavage results in children. The national institute of clinical excellence (NICE) guidelines recommends chest radiographs for the diagnosis of active tuberculosis but not for diagnosing latent tuberculosis. These guidelines are based on the evidence derived from four studies, none of which were done in the UK and only one of those was performed in children. Objective (1) To demonstrate the radiographic patterns of pulmonary tuberculosis in the paediatric population of the UK. (2) To demonstrate inter-observer variability and value of serial radiographs in the diagnosis and management of pulmonary tuberculosis. Materials and methods A database of all children who were treated for pulmonary tuberculosis was collated. Children who were clinically diagnosed as latent tuberculosis or active pulmonary tuberculosis on the basis of exposure, skin testing, clinical symptoms, Interferon Gamma test and had anti-tuberculous treatment were included. The data base consists of 220 cases over the past 10 years. Two paediatric radiologists were blinded to the cases and assessed chest radiographs for radiographic patterns and resolution of changes over the course of treatment. Results This is an on going study and to date seventy cases have been analysed. This study is due to finish in the next 2 months. Analysis will highlight radiographic differences between active and latent tuberculosis and between sputum confirmed tuberculosis and sputum negative tuberculosis. 029 Superior cervical extension of the thymus: a common normal variant that should not be mistaken for a mass Norma S Costa, Lane F Donnelly, Tal Laor Cincinnati Children’s Hospital Medical Center, USA
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Background We recently have seen several outside CT studies of children and young adults referred to us for suspected anterior neck masses that in actuality represented superior extent of the thymus in the anterior midline, above the manubrium. Our hypothesis is that anterior midline superior extension of the thymus is a common normal variant in young patients. This is different than ectopic cervical thymus, an embryonic remnant of thymus that is located in the posterolateral portion of the neck. Objective To evaluate neck and upper chest MRI examinations performed in children and young adults to determine the frequency at which the thymus demonstrates superior extension above the level of the manubrium into the anterior cervical tissues. Materials and methods Sagittal proton density MRI images of the neck and upper chest (performed for clinical reasons) from 100 patients, 57 males and 43 females, (ages 1 month–23 years, mean age 7.6 years), were reviewed for frequency of cervical thymic extension. Cervical extension was defined as present when a superior lobe of the thymus (homogeneous, contiguous, and similar in signal intensity to the remainder of the thymus) was seen to extend at least 5 mm superior to the notch of the manubrium. The distance that the thymus extended above the manubrium was measured. Any patient with an intrinsic thymic abnormality was excluded. Results Sixty-six (66%) children and young adults had cervical extension of the thymus. In all cases, the superior cervical extension was anterior and near midline, anterior to the trachea. No patient showed tracheal compression. The mean distance of extension above the notch of the manubrium was 18.3 mm, with a range of 6.5; 29.7 mm. Conclusion Superior cervical extension of the thymus is a common normal variant in children and young adults and should not be mistaken for a mass. 030 A software tool for automated classification of funnel chest Erich Sorantin, Laszlo Papp, Reka Juhasz, Sonja Travar, Stefan Pokall, Alexander Kolli Department of Radiology Graz, Austria Background Usually people affected by funnel chest suffer from altered body shape, therefore operative correction is desired frequently. Until now characterization and grading of funnel chest was on based indices derived from chest films as well as on a visual, semiquantitative scoring system of low dose chest computed tomography studies, performed preoperatively. Due to the invasiveness of surgical approaches an exact, non operator dependent and therefore objective scoring system would be desirable in order to enable adequate preoperative patient selection. Objective Presentation of a new, image based, objective software tool based on chest CT for characterization and grading of funnel chest. Materials and methods One hundred thirty-one patients with funnel chest were derived form the hospitals PACS system as well as 68 individuals with no chest deformation, forming the control
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group. For all 131 patients the visual grading system was available obtained by a radiologist. The workflow consists of the following steps: (1) identification of the slice representing the biggest deformation (2) detect inner chest curvature by image processing (3) obtain curvature and deformity indices by the software (4) classification. Besides step I all others do not need any user interaction. Verification was done by calculating the accuracy of the automated classification compared to the visual grading system. The software was implemented using the “Integrated Data Language” (Creaso, Boulder, Inc.), running on almost any computer and operating is prsystem. Results Accuracy of the automated classification could be achieved as follows: normal individuals 100%, borderline: 88.9%, different subtypes of funnel chest with between 93.4% and 100%. There was only one exception in the group of symmetric narrow funnel chests, were accuracy was 84%, which can be explained by the fact, that is group consisted of only seven patients. Conclusion Based low dose chest ct a novel, objective method for classification of funnel chest with high accuracy could be developed.
Reserve
R-031 Tracheomalacia and tracheomegaly as complications of fetal endoscopic tracheal occlusion in the treatment of congenital diaphragmatic hernia K McHugh, A Afaq, N Broderick, H Gabra, MJ Elliott, DJ Roebuck Great Ormond Street Hospital, London/UK Background Fetal endoscopic tracheal occlusion (FETO) is a promising treatment for congenital diaphragmatic hernia; a condition which carries a significant morbidity and mortality. It is hypothesised that balloon occlusion of the fetal trachea leads to an improvement in lung growth and development. The major documented complications of FETO are related to preterm delivery. Objective To report a series of five patients who developed tracheomalacia and tracheomegaly following FETO. Materials and methods Retrospective database review of all patients referred to the paediatric intensive care and tracheal service at two referral centres. Results Five neonates presented with features of respiratory distress shortly after birth and were subsequently found to have significant tracheomalacia and/or tracheomegaly. Conclusion There are no previous reports in the literature describing tracheomalacia or tracheomegaly as a consequence of FETO. We propose that the particularly compliant fetal airway is at risk of mechanical damage from in utero balloon occlusion. The exact incidence of this complication is not known but is likely to be >3%.
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Scientific Session 4: Oncology
032 Imaging in high-risk hepatoblastoma (HB) DJ Roebuck Great Ormond Street Hospital, London, UK Background The International Childhood Liver Tumor Strategy Group (SIOPEL) stratifies HB patients with any of the following as high risk: PRETEXT IV, direct extrahepatic spread of tumor, metastasis, involvement of the IVC and/or all three hepatic veins (V3), or the portal vein and/or both of its branches (P2), tumor rupture, serum alpha-fetoprotein <100 μg/L. Objective To describe imaging features in children with high-risk HB. Materials and methods Analysis of imaging studies referred to SIOPEL for central review. Results Forty children with suspected high-risk HB were referred for review in a 40-month period. One child was reclassified as standard risk at central review and was excluded from further analysis. The age range of the remaining children was 2 months to 16 years. Local staging showed PRETEXT I in two patients (5%), II in 12 (27%), III in 19 (43%), and IV in 11 (25%). The caudate lobe (segment 1) was involved in 22 patients (50%). Multifocal liver tumor was present in 15 (34%). There was evidence of tumor rupture, ascites, and/or direct growth of tumor into adjacent structures in six (14%), 10 (23%), and five (11%) patients respectively. Thirty patients (89%) had involvement of one or more hepatic vein, but only 12 (27%) were V3. Similarly, although 31 (70%) had some portal venous involvement, only ten (23%) were P2. CT images covering of all of both lungs were available in 41 children (93%). Of these, 27 patients (66%) had lung lesion(s) compatible with metastasis. No other forms of metastasis were detected in any child. Conclusion Conclusions are limited by referral bias. Contrary to previous assumptions, the caudate lobe is frequently involved in HB. Certain staging findings have an intermediate frequency, suggesting that they are potentially useful prognostic markers. The lungs are the only common site of metastatic disease at diagnosis. 033 DWI to assess chemotherapy response in solid tumours Kirsteen MCDonald, Oystein E Olsen, Neil Sebire, John Anderson Great Ormond Street Hospital, London, UK Background Calculated apparent diffusion coefficients (ADC) correlate with cellularity of tumours, and may be useful in assessing chemotherapy response. Objective To compare change in ADC over the course of chemotherapy with post surgical histopathology in solid tumours. Materials and methods Seven children with solid tumours had MRI pre and post chemotherapy. Regions of interest including the whole tumour were drawn on the central three slices. Median ADC before and after chemotherapy was compared to the histopathology of the resected tumours.
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Results Four boys, three girls, aged 5 months to 2 years, mean age 0.7 years. In two, tumour remained of similar size, with an increase in median ADC values, reflecting rhabdomyomatous differentiation (n=1, Wilms’), and >50% necrosis (n=1, Wilms’). In two, the tumour shrunk, but the median ADC values remained unchanged, reflecting >90% viable tumour (n=1, Wilms’). The histopathology was not available for the second patient. In one, there was a slight increase in size with unchanged ADC, reflecting no chemotherapy response (n=1, Wilms’). In two, tumour decreased in size with increased median ADC values, reflecting post chemotherapy differentiation (n=1, neuroblastoma) and no viable tumour (n=1, neuroblastoma). Conclusion The results suggest that increased ADC reflects tumour necrosis or differentiation, whilst unchanged ADC reflects viable tumour. 034 Whole-body MR imaging, including diffusion-weighted imaging, for staging malignant lymphomas in children: Direct comparison to CT initial experience TC Kwee, HME Quarles van Ufford, FJ Beek, MA Bierings, WP Mali, RAJ Nievelstein University Medical Center Utrecht Background CT is the most commonly used method for staging malignant lymphoma, but uses ionizing radiation, which may cause secondary cancers (which is especially of concern in children). MRI may be an attractive radiation-free alternative. Furthermore, in addition to conventional MRI, the recently developed concept of whole-body diffusion-weighted imaging (DWI) may facilitate staging. Objective To evaluate the feasibility of whole-body MRI, including DWI, for the initial staging of malignant lymphomas in children, and assess its equivalence to CT. Materials and methods Nine children (five males, four females; mean age, 15 years; age range, 12–17 years) with newly diagnosed malignant lymphoma prospectively underwent wholebody MRI [T1-weighted and T2-STIR (n=9) and DWI (n=8)], and CT. A pediatric radiologist, blinded to CT and other imaging findings, assigned an Ann Arbor stage according to whole-body MRI (without and with DWI). Another pediatric radiologist, blinded to MRI and other imaging findings, assigned an Ann Arbor stage according to CT. Staging results according to wholebody MRI (without and with DWI) were compared to those of CT. Results Staging results of whole-body MRI without DWI were equal/higher/lower to those of CT in 78% (7/9), 22% (2/9), and 0% (0/9) patients, respectively. Staging results of whole-body MRI with DWI were equal/higher/lower to those of CT in 75% (6/ 8), 25% (2/8), and 0% (0/8) patients, respectively. Conclusion Our initial results indicate that staging using wholebody MRI (without and with DWI) is equal to staging using CT in the majority of patients, while whole-body MRI never understaged relative to CT. FDG-PET and follow-up studies should validate and determine the possible consequences of overstaging relative to CT. Nonetheless, whole-body MRI, including DWI, is feasible for staging malignant lymphoma in children.
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035 Normal bone marrow signal distribution on body-DWIBS in a healthy paediatric population Lil-Sofie Ording Müller, Derk F M Avenarius, Petter Eldevik University Hospital North Norway Background Diffusion weighted total body imaging with background suppression (DWIBS) is a novel standard sequence in adult body MRI that has increased the sensitivity for bone marrow and other diseases. DWIBS has lately been introduced in the paediatric population. Bone marrow signal in children differs from adults´ and this causes interpretation problems. Age related bone marrow signal in children has been studied with other MRI-series, but DWIBS data in a healthy paedriatic population is lacking. Objectives To study the signal on DWIBS-sequence in a paediatric population with no suspicion of bone marrow disease. Material and methods We have started studying DWIBS signal of bone marrow in normal children and we intend to image 30 healthy volunteers age 5–12. In addition, we add DWIBS on all paediatric patients referred to MRI with no suspicion of bone marrow disease. Results and Conclusion We want to assess the age-related distribution of DWIBS signal in bone marrow in children. We intend to present preliminary results of this study. 036 Added value of abdominal cross-sectional imaging (CT or MRI) in staging of Wilms’ tumours Kirsteen Mcdonal, Kieran Mchugh Great Ormond Street Hospital, London, UK Background In the UK children with probable Wilms’ tumours are staged with an abdominal ultrasound, plus CT or MRI of the abdomen. Objective As reliance in some countries is placed solely on abdominal ultrasound in children undergoing staging of Wilms’ tumour, we assessed the added information gained from CT or MRI abdomen. Materials and methods Fifty-two consecutive patients with histologically proven Wilms’ tumours were identified. Each had an initial staging abdominal ultrasound followed by either a CT or MRI scan of the abdomen. Details including: tumour size, site, and characteristics; presence of lymph nodes, local invasion, evidence of nephroblastomatosis, and any other relevant finding were gathered from the report of each ultrasound and CT or MRI. Each CT/MRI was then rereviewed by a Consultant Paediatric Radiologist and Paediatric Radiology Fellow. The difference in findings between the ultrasound and cross-sectional imaging were noted. Results Twelve patients were excluded from the study because the CT/MRI was performed before the ultrasound, or imaging was incomplete. 26 patients were female, 14 male. The ages ranged from 9 months to 10.8 years (mean 3.75 years). Twenty-one patients out of the remaining 40 had additional findings detected on the CT or MRI scan that had not been reported on the ultrasound. The most important additional findings included three patients with nephroblastomatosis and two with contralateral tumours. Other findings included six patients with tumour haemorrhage/rupture, four with abdominal lymph node enlarge-
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ment, three with IVC/renal vein thrombus, four with adjacent organ invasion, one patient where the origin of the abdominal tumour was confirmed as renal, and one patient where possible liver invasion was excluded. Conclusion In over half the patients CT or MRI imaging added additional information in the local staging of Wilms’ tumours. Sole reliance on ultrasound for Wilms’ staging risks missing significant abnormalities. 037 Imaging of ovarian teratoma in children: a 9-year review Mohammed O Alotaibi, Oscar Navarro University of Toronto, Hospital for Sick Children, Canada Background Germ cell tumours are the most common ovarian neoplasms in childhood and of those the teratoma, whether mature or immature, are the most frequently found. Mature teratoma is a benign tumor, whereas the immature type, although also benign, has a more aggressive course with propensity to recurrence. Objective We intended also to find any differentiating imaging features between the mature and immature type of ovarian teratomas. Materials and methods This was a retrospective analysis of all pediatric patients who presented to our institution during the 9-year period September 1999–August 2008 with ovarian teratoma as confirmed on histology. Results Forty-one patients with pathologically proven ovarian teratoma were found. The patients ages ranged from 4 to 18 years at presentation, with a mean age of 12.4±3.4 years. The median age was 13 years. Thirty (73.1%) patients were found to have mature ovarian teratoma and 11 (26.8%) had immature teratoma. A component of endodermal sinus tumor was found in one of the immature teratoma. On US, the appearance of the immature teratomas varied from solid to cystic with three appearing purely solid(27.3%), six mixed solid and cystic (54.5%), and two (18%) predominantly cystic. Of the mature ovarian teratomas, 22 (73.3%) demonstrated a predominantly cystic appearance, eight (26.6%) had a mixed solid and cystic appearance, and there were no cases with a pure solid appearance. The prevalence of the more cystic appearance of the mature type showed significant statistical difference when compared to its prevalence in the immature type (p=0.0008, chi square test). Conclusion We conclude that the predominance of cystic component within the ovarian teratoma is an important differentiating factor between the mature benign type and the more aggressive immature type of teratoma.
Scientific Session 5: Neuroimaging
038 Cerebral magnetic resonance imaging and cognition of non handicapped, low birthweight adults: a population based controlled study Morten Duus Odberg1, Stein Magnus Aukland2, Karen Rosendahl3, Irene Birchow Elgen4
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Institute of Clinical Medicine, Section for Paediatrics, University of Bergen & Department of Child and Adolescent Psychiatry, Haukeland University Hospital, Bergen, Norway1, Institute of Surgical Sciences, Section for Radiology, University of Bergen & Department of Radiology, Haukeland University Hospital, Bergen, Norway2, Institute of Surgical Sciences, Section for Radiology, University of Bergen, Bergen, Norway & Department of Radiology, Great Ormond Street Hospital for Children, London, UK3, Institute of Clinical Medicine, Section for Paediatrics, University of Bergen & Department of Paediatrics, Haukeland University Hospital, Bergen, Norway4 Study Design Population based longitudinal follow-up study. Objective To assess structural MRI markers for previous brain injury at age 19 years, and to investigate correlation between findings on MRI and cognition (IQ) and association between structural MRI findings and pre-, peri- and neo-natal factors. Materials and methods A cohort of 173 young adults born with a birthweight (BW) <2,000 g (LBW), and 170 controls born with a BW >3,000 g (NBW) were invited to participate in the study. 113 (65%) LBW young adults and 100 (59%) controls participated. Cerebral MRI was performed on a GE Signa Excite HD 3.0 T scanner, including a transversal T2 weighted sequence and a double set of high-resolution sagittal T1 weighted volume sequences. Two experienced neuroradiologists masked for BW status scored the images. Prorated IQ was estimated from two subtests of the Wechsler abbreviated scale of ability (WASI); word comprehension test and matrixes. Results IQ was lower for subjects born with LBW than for those born with a normal BW [95 (SD 13) vs.101 (SD 14) P=0.001]. Dilated ventricles and loss of white matter, as well as thinning of the callosal body were more common in the LBW group (40% vs. 15%, OR 3.8, P<0.001 and 31% vs. 7%, OR 6.0, P<0.001). Conclusion MR-findings such as dilated lateral ventricles, global loss of white matter or thinning of the corpus callosum were seen in 40% of those born with a BW below 2,000 g compared to 15% of healthy controls born with a BW >3,000 g. There were no differences between those below 1,500 g and those with BW’s s between 1,500 and 2,000 g. No specific markers for being born LBW were identified. No correlation between the structural MRI findings neither to IQ nor to pre- peri- or neonatal data were found. 039 Growth rates of tectal gliomas in children and young adults assessed by serial tumor volume measurements Korgun Koral, Barjor Gimi, Lynn Gargan, Amir Kerschenovich, Daniel Bowers University of Texas Southwestern Medical Center Background A series of pediatric tectal gliomas was presented and their growth patterns were studied. This was the largest series of pediatric tectal gliomas for which long follow-up was available. Objective To identify growth rates in tectal gliomas in children and young adults on consecutive MR imaging and seek optimal follow-up interval. Materials and methods Review of neuro-oncology database from January 1996 through May 2008 yielded 29 pediatric tectal region
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tumors. Patients who had neurofibromatosis type I, enhancing tumors and whose tumors have been biopsied/resected were excluded. Thirteen patients (ten males, three females; 2.3–23.8 years, mean age 9.1 years) were included in the study. Patients were followed-up for 1.8–10.0 years (mean follow-up 6.3 years). Average number of scans was seven (4–17). Tumors were measured in three planes using anatomical MRI and tumor volumes were calculated using the formula for an ellipsoid. Using the ellipsoid formula 91 tumor volume measurements were made. Subsequently, 70 of the aforementioned 91 time points were sampled using imageJ (NIH, Bethesda, MD). For each patient and for both measurement strategies, a linear fit for tumor volume vs. time was performed and the slope used to compute the change in tumor volume per annum. Results The average annual change in tumor volume was 10% for ImageJ measures and 18% for the ellipsoid measures. For both measurement strategies, 11 of 13 patients had less than a 20% change in tumor volume per annum. The tumor volumes obtained from ImageJ analysis strongly correlated to those obtained from manual measurements using the ellipsoid formula (R2 =0.83). Conclusion Tectal gliomas in children and young adults are rare tumors and the majority of tumors demonstrate volume change very slowly. Short term follow-up is unlikely to yield appreciable change in tumor volume. 040 Imaging characteristics of pilomyxoid astrocytomas, comparison with pilocytic astrocytomas Ji Hye Kim, Myung Kwan Lim, In Ho Lee, Honh EO, So Young Yoo Samsung Medical Center, Sungkyunkwan University Background Pilomyxoid astrocytoma (PMA) is a recently described astrocytic tumor, which has been previously diagnosed as pilocytic astrocytoma (PA). Objective To describe the imaging and clinical findings of PMAs comparing with those of PAs. Materials and methods We retrospectively reviewed CT and MR images and medical records of nine patients with PMA and 39 patients with PA. Special attention was paid on clinical manifestations, tumor location, composition, MR signal intensity (SI) and CT attenuation, presence of calcification, hemorrhage, enhancement, and leptomeningeal dissemination. Results Mean age of the patients with both tumors all 10 years. Gross total removal was performed in three (33%) of the patients with PMA and 21 (54%) patients with PA. Recurrent tumor or disease progression was noted in four (44%) PMAs and 14 (36%) PAs and chemo- or radiation therapy was performed in five (56%) patients with PMA and 14 (36%) patients with PA. Locations of the tumors were suprasellar (56% in PMA, 23% in PA), cerebellum (22% in PMA, 38% in PA), and others (22% in PMA, 38% in PA). Both groups of tumors were solid and cystic in variable composition. The solid component of the tumor became bright on T2-weighted images and showed variable SI on T1weighted images. Four (44%) PMAs included non-enhancing solid portion while all PAs were well enhanced. On CT scans, 7 of 9 (78%) PMAs and 29 of 30 (97%) PAs were less attenuated than normal parenchyma. Calcification and hemorrhage were noted in a small number (5–11%) of the patients. Leptomeningeal dissemi-
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nation was noted in five (56%) patients with PMA and one (3%) patient with PA. Conclusion PMAs exhibited more frequent occurrence at the suprasellar area, less enhancement, more frequent leptomeningeal dissemination, and higher tendency to need additional therapy due to dissemination or disease progression than PAs. 041 Anatomical location and noninvasive magnetic resonance spectroscopic imaging biomarkers in pilocytic astrocytomas L Porto, M Kieslich, D Schwabe, U Pilatus, E Hattingen Uniklinikum Frankfurt Background Pilocytic astrocytomas are common childhood brain tumours whose management and prognosis vary widely depending on location. Objective To investigate whether proton magnetic resonance spectroscopic imaging (MRSI) can identify differences with anatomical location in pilocytic astrocytomas. Materials and methods Twenty-one primary brain lesions were evaluated retrospectively. 1H-MRS and MR imaging (MRI) were performed before surgery in all patients with histologically proven pilocytic astrocytomas. The tumors were divided in supra (n=14) and infratentorial (n=7). Metabolite concentrations of cholinecontaining compounds (Cho) and creatine/phosphocreatine (tCr) were normalized to contralateral brain tissue. Spectroscopic data as well was used for statistical evaluation Results Considering all metabolite ratios, the best discriminant function to differentiate between supra and infratentorial pilocytic astrocytomas was found to be the Cr with positive Mann–Whitney U-test (median-Cr supratentorial: 50%; medianCr infratentorial: 80%). The median Cho levels were 120% for both groups. Conclusion Normalized values of tCr was statistically different for supra and infratentorial pilocytic astrocytomas. 042 MRI and DWI findings in children with hemophagocytic lymphohistiocytosis: tendency for symmetricity E Senocak, KK Oguz KK, B Ozgen, S Aytac, A Cila, A Gurgey Hacettepe University Faculty of Medicine Background Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical disorder characterized by uncontrolled hemophagocytosis and release of inflammatory cytokines that may affect central nervous system (CNS). Reported abnormalities on brain imaging include atrophy, parenchymal lesions that may have nodular or ring enhancement, calcification, leptomeningeal and perivascular enhancement, and subdural fluid collections. Objective The aim of this study is to investigate MRI characteristics of CNS in primary HLH diagnosed in Turkey between 2002 and 2008. Materials and methods There were eight patients with an age range of 7 months to 16 years. All patients had conventional contrast-enhanced cranial MRI and diffusion-weighted imaging (DWI) on a 1.5 T MR system.
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Results We observed tetraventricular hydrocephaly in one, cerebral/ cerebellar atrophy in two, leptomeningeal involvement in one patient. Five patients had supratentorial mostly corticomedullary lesions that tended to be symmetrical. Other sites of involvement were periventricular white matter, centrum semiovale, thalamomesencephalic junction, posterior limbs of the internal capsules, bilateral hippocampus, deep grey matter and splenium of corpus callosum. Hemorrhage was present around the lesions in two patients. The lesions had mass affect in one and enhanced in peripheral and/or nodular pattern in four patients. Three had cerebellar, and 3 had brainstem involvement. The lesions had most frequently elevated apparent diffusion coefficient (ADC) values (6/8 patients). Conclusion MRI findings may vary among individuals. However extensive infra- and supratentorial lesions that tended to be symmetrical is a frequent observation in patients with primary HLH. Enhancement is not a rule, when present nodular or peripheral enhancement patterns are observed. Lesions on acute phase may show restricted diffusion. 043 Functional MRI findings in Chinese (non-alphabetic) reading dyslexia children: what is different from alphabetic-language dyslexics? Winnie CW Chu, Sarah SH Luk, Defang Wang, Lin Shi, David KW Yeung, Mary Waye, PW Cheng, Anil T Ahuja The Chinese University of Hong Kong Background Recent fMRI studies for dyslexic readers of English (alphabetic) language dyslexics showed reduced activity at left temporoparietal and occipitotemporal regions. As Chinese (nonalphabetic) language relies on arbitrary association between character forms and pronunciation (graphic forms are mapped to syllables), the functional disturbance in Chinese dyslexic readers might be different from the Western readers. Objective To determine the regional difference of brain activations between dyslexic Chinese children and age matched normal controls. Materials and methods Twenty-three Chinese dyslexia children (14 boys, nine girls, mean age 8 years, 8 months, SD 10 months) and six typically developing age matched controls (four boys and 1one girl, mean age 8 years, 1 month, SD 13 months) were recruited for participating in a fMRI experiment using word recognition and comprehension as an experimental task in a blocked design. All children were native speakers of Cantonese, the major dialect of Hong Kong and the language of instruction in school. They were strongly right-handed. Results Dyslexic children showed reduced activation at left parahippocampal and left frontal superior and left frontal mid region when compared with normal controls. On the other hand, dyslexic children showed greater right hemispheric activation in a variety of regions closely related to the contralateral hemisphere including right parahippocampal, right frontal mid and right frontal inferior region (two sample t test, p<0.001 uncorrected). Conclusion Neural circuits involved in reading disorder seem to vary across language. Chinese dyslexia demonstrated functional abnormality involving mainly frontal and temporal regions (for processing of logographic Chinese), which are different from the
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more posteriorly located temporoparietal and occipitotemporal regions involved in processing of English (alphabetic) language. Regions in non-dominant hemisphere might be recruited to support compensatory reading strategies in Chinese dyslexia. 044 Impact of susceptibility weighted imaging in management of pediatric neurologic diseases Aylin Tekes, Gulhan Ertan, Jason Schroeder, Thierry Huisman Johns Hopkins Hospital Background Use susceptibility weighted in pediatric patients and impact on management has not been well established. We used SWI in various pediatric neuorologic diseases to evaluate the significance on diagnosis and management. Objective To assess the role of SWI in evaluation of various neurological disorders, and its impact on patient management. Materials and methods We studied 20 children (mean age, 5; six females, and 14 males), with suspected diagnosis and further evaluation of hydrocephalus, seizure, brain tumor, Sturge–Weber syndrome, traumatic brain injury and vascular malformation. All patients had brain MRI in a 1.5 T MR scanner, using axial GRE T1, axial FSE T2, DTI, SWI and post contrast triplanar imaging if necessary. Two pediatric neuroradiologists retrospectively evaluated the images in consensus. Presence of hemorrhage/calcification was evaluated in SWI against the remainder of the pulse sequences and diffusion weighted images. Results SWI was superior in identifying presence of hemorrhage in five patients where the remainders of the sequences were negative for hemorrhage. SWI better defined the extent of disease in 11/20 patients. Two patients did not show any evidence of hemorrhage or calcification neither on SWI nor other sequences. In two patients SWI did not contribute additional information. In the light of information provided by SWI, four of 20 patients clinical care and management changed Conclusion SWI provides useful information in defining presence and extent of hemorrhage. SWI not only makes hemorrhage and calcification more conspicuous but also defines presence of hemorrhage and calcification with better accuracy. Our data implies the importance of implementing SWI in pediatric brain MRI protocols as extent and presence of hemorrhage can be better defined with this sequence, which ultimately impacts clinical care and management of diseases. 045 Diffusion weighted magnetic resonance imaging for demonstration and characterisation of borderzone necrosis in paediatric tuberculous meningitis Nadir Omar, Savvas Andronikou, Ronald van Toorn, Manana Pienaar University of Stellenbosch, South Africa Background Tuberculous meningitis (TBM) is associated with the occurrence of borderzone necrosis (BZN). Diffusion weighted MRI (DWI) is a relatively new tool allowing accurate detection of
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cytotoxic oedema that may be associated with BZN. Detection of BZN using DWI and establishing anatomical prevalence to further attempt to explain its pathogenesis has not been performed previously in paediatric TBM. Objective To identify the prevalence of and characterize borderzone necrosis using DWI in children with TBM and to correlate it with the presence, degree, and distribution of basal enhancement in the absence of large vessel thrombosis. Materials and methods A retrospective descriptive study of 34 paediatric TBM patients referred for MRI. The presence by location of BZN was recorded and compared to BE presence and severity, large vessel occlusion and apparent mottling of the middle cerebral arteries (MCAs) on specific MRI sequences. Results BZN was identified on DWI in 50% of patients. Eightytwo percent had temporal lobe involvement. MCA mottling occurred in 29%. Statistically significant correlation existed between BZN and BE distribution in either MCA cistern. BZN adjacent to the right MCA cistern correlated with MCA mottling. BZN did not correlate with vascular occlusion. Conclusion BZN is common in TBM occurring in 50% of children and reportedly predicts a poor outcome. This may be because of its demonstrated temporal lobe propensity, helping us understand the often-resulting poor neurological outcome. DWI and ADC mapping detection and confirmation of BZN-associated cytotoxic oedema, and its clear relation to BE supports existing pathogenetic descriptions. Mottling of the MCA on T2 predicts BZN on DWI which may act as a surrogate marker of BZN in the absence of DWI to predict outcome. 046 Accuracy of CT scan in the diagnosis of non-tuberculous bacterial meningitis and its complications in children: a retrospective study RP Singaroyan, DJA Connolly, A Raghavan Sheffield Children’s Hospital, Royal Hallamshire Hospital, UK Background The role of CT scan in suspected non-tuberculous early bacterial meningitis in children has been to exclude alternate diagnosis and complications of meningitis. Recent studies of the diagnostic accuracy of CT in tuberculous meningitis have showed high accuracy. A similar study in non-tuberculous bacterial meningitis is lacking. Objective (1) To demonstrate the diagnostic accuracy of 13 known CT signs of bacterial meningitis and its complications. (2) To evaluate inter-observer variability and detection rates of individual signs/complications Materials and methods Two groups of CT scans were independently analysed by two paediatric neuroradiologist who were blinded to the final diagnosis. Group A consisted of 30 children who had confirmed non-tuberculous bacterial meningitis and were scanned within 48 hours of admission. Group B consisted of 29 children who had under gone CT scans for other indications and had previously been reported as normal by a paediatric neuroradiologist. Results were collated on a performa
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on a named patient basis. Both neuroradiologist evaluated the scans for 13 known signs of meningitis and documented their findings on the performa along with their final diagnosis. Statistical analysis was performed on the data to evaluate the over all diagnostic accuracy and the diagnostic prowess of individual signs. Results The specificity, positive predictive value were high as a 100% for a number of signs (ventricular debris, cortical infarction, surface collection, basal ganglia changes and loss of grey/white differentiation). These signs also had good concordance. Sensitivity was 55% and specificity was 97% and 86% for both neuroradiologist in the diagnosis of meningitis. Conclusion CT cannot be used as a sole diagnostic tool in nontuberculous bacterial meningitis. However the 100% specificity and positive predictive value of some signs proved that when present they can be improve diagnostic accuracy and have a significant impact on clinical management 047 Imaging of petromastoid canal in children on high-resolution temporal bone MR Korgun Koral, James Sayre, Edgar Suter, John McMenamy, Neil Fernandez, Timothy Booth University of Texas Southwestern Medical Center Background MRI characteristics of petromastoid canal were not previously described. Imaging characteristics of petromastoid canal (PMC) were studied with MRI in children. The frequency of visualization was identified and correlated with age and sex. Objective To describe the MR imaging characteristic of PMC in children. Materials and methods Four hundred eighty-five high resolution temporal bone MRI studies performed for clinical indications were retrospectively evaluated. Twelve patients with dysplastic semicircular canals were excluded. There were 264 males and 209 females. The mean age was 6.50 years (0.16–18.09, SD± 4.51). Measurements were made on the axial T2 weighted images. The patients were separated into three age groups (group I: <1 year; group II: >1 and <2 years; group III >2 years). Results The PMC was most frequently visualized in children younger than 1 year (26/60 on right, 24/60 on left; 43.3% and 40.0%, respectively). The detection rate of PMC decreased precipitously after 1 year [in group II: 6/35 (17.1%) on right, 2/ 35 (5.7%) on left; in group III: 18/377 on right (4.8%), 8/377 on left (2.1%). There was moderate to large dependency to age in detection of PMC (Cramers V coefficient of contingency was 0.534 for left and 0.427 for right, p<0.001). The mean size of the PMC decreased with age (p<0.001). Conclusion Familiarity with the normal appearance of PMC on high resolution MRI is important for pediatric temporal bone imagers. In younger children, the PMC is relatively large and is more frequently detected. After 1 year of age the detection rates decreases.
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048 Persistent conductive hearing loss in children: evaluation with temporal bone CT Aylin Tekes, Stacey Ishman, Katherine Baugher, David J Brown, Sandra U Lin, David E Tunkel, Thierry AGM Huisman Johns Hopkins Hospital Background Imaging of temporal bone CT in children with persistent conductive hearing loss. Objective To determine the etiology of persistent pediatric conductive hearing loss (CHL) in children and determine the utility of temporal bone computed tomography (CT) to identify etiology of persistent CHL Materials and methods Three thousand three hundred ninety-six pediatric records with conductive hearing loss from 1993 to 2008 were reviewed, revealing 180 cases of persistent conductive hearing loss. Thirty-seven had diagnostic temporal bone CT scans available for review. Thin slice bilateral temporal bone CT’s were performed either with axial and coronal planes, or axial images with coronal reformats, without contrast administration. Two pediatric neuroradiologists evaluated the temporal bone CT’s in consensus. External auditory canal, tympanic membrane, middle ear cavity, ossicular chain, oval window, round window, cochlea, vestibulum. Results Twenty-two of 37(59%) had a microtia, unilateral or bilateral atresia/stenosis. Twenty-one of 22 (95%) had multiple anomalies. Of the 15 without microtia/atresia or stenosis, five (33%) had normal CT scans bilaterally. Seven of 15 (47%) had multiple anomalies: Six (40%) had ossicular malformation, five (33%) had mastoid air cell abnormalities, three (20%) had oval foramen abnormalities, two (13%) had abnormalities of the middle ear, one (7%) had an aberrant facial nerve course and two (14%) had vestibular or semicircular canal abnormalities. Overall, 28 (76%) had multiple anomalies. Temporal bone CT accurately identified of the etiology of persistent CHL in 32/37 (86.5%). Conclusion Microtia, atresia and stenosis were the most common anomalies seen in persistent CHL. In those patients without microtia, atresia or stenosis, ossicular chain and external auditory canal abnormalities were most common. Temporal bone CT evaluation is useful in identifying the etiology of conductive hearing loss, enabling accurate diagnosis and full extent of the disease thus providing better patient management. Attention should be paid to presence of multiple congenital anomalies in evaluation of persistent CHL. 049 Utility of high resolution MRI of the orbit in pediatric patients M Basile, M Mortilla, N Decaminada, M Cappellini, C Fonda A Meyer Children’s University Hospital-Firenze-Italy Background High-resolution MRI (HR-MRI) is a powerful noninvasive tool that provides images of higher spatial resolution. The eye is an ideal organ for imaging with this technique because of its
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wide variation in water content and the requirement of high spatial resolution in a small field of view. Objective The purpose of this study is to investigate the efficacy of a HR-MRI in ocular pediatric pathology. Materials and methods Thirty-five pediatric patients (age range, 6 months–5 years) with different ocular pathology (retinoblastoma, retinal detachment, congenital anomalies, inflammatory conditions and injures) have been examined using surface microscopic coils of 47 and 23 mm inner diameter with commonly available 1.5 T scanner (Philips, Achieva, Nova Qasar).Twenty patients has been also imaged with high-frequency ultrasound which is the gold standard in ocular pediatric imaging. The examination protocol includes conventional sequences in all three planes (axial, coronal and sagittal) with or without administration i.v. of mdc. The imaging employed a FOV of 90 mm, acquisition matrix of 256×224, and slice thickness of 2 mm with interslice gap 0.2 mm. 3D sequences and fat suppression technique have been also performed. Results The higher resolution of microscopic coil is compared with conventional or neurovascolary coil usually used to imaging brain and with ultrasound. The imaging results focus on identification of single anatomic structures of the orbit, and detailed analysis of changes in pathological cases. Conclusion HR-MRI of the orbit is a method to accurately demonstrate normal and pathological conditions widely improving the diagnostic accuracy. Despite limitations of this technique such as eye movements, sedation and gradual decrease signal intensity with increasing distance of coil, the high signal/noise ratio, the optimal spatial resolution and relatively fast time acquisition represent further advantages that suggest HR-MRI together with ultrasound in imaging oftalmopathology. 050 MRI findings of Charlevoix–Saguenay patients from Turkey: additional pyramidal tract abnormalities on imaging Kader Karli Oguz, Goknur Haliloglu, Ersin Tan Hacettepe University Department of Radiology, Department of Pediatric Neurology, Department of Neurology Background Autosomal recessive spastic ataxia of Charlevoix– Saguenay (ARSACS) is a rare neurodegenerative disorder characterized by usually early-onset spastic ataxia, progressive cerebellar and pyramidal syndrome, extremity deformities, and hypermyelination of nerve fibers in fundoscopic examination. However, there is a range of clinical phenotypes of the disease in patients from areas other than Quebec which makes diagnosis harder. Objective To report MR imaging findings of additional three patients from Turkey. Materials and methods Performed on a 1.5 T system, conventional (c) cranial MR imaging were available in all patients with a diffusion-tensor imaging (DTI) in one patient. Results Cerebellar atrophy prominent on upper vermis, two parallel T2-hypointense lines with an anteroposterior orientation in the pons were present. Apart from these previously reported findings, we observed symmetrical linear T2-hyperintensity medial to the posterior limbs of the internal capsules. DTI
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disclosed these abnormalities belong to the pyramidal tracts with decreased fractional anisotropy, and increased mean diffusivity. Conclusion Peculiar radiologic abnormalities of the pyramidal tracts in addition to upper vermian atrophy play major role in diagnosis of ARSACS in the clinical setting of progressive cerebellar spastic ataxia given the wide variability of clinical phenotypes especially in non-Quebec patients. 051 White matter changes in MRI in children with complex migraines Monica Rebollo Polo, Eoghan E Laffan, Daniel L Keene, Hazar Tabban, Husain Naser Children’s Hospital of Eastern Ontario Background Complex migraines are an uncommon subgroup of migraines associated with confusion, ophthalmoplegia or hemiplegia. They are a diagnosis of exclusion in a child with headaches. White matter changes (WMC) in MRI have been described in the literature in adults with migraines. There are very few case-reports describing these changes in children. Objective We describe the WMC seen in MRI in three children with complex migraines. Materials and methods Three children (two females, one male), age range (10–17) were investigated for headaches associated with acute confusion or transient motor symptoms. The symptoms resolved completely in each case but recurred on several occasions. All of them had strong family history of migraines. All children had an MRI at the time of initial presentation and follow up MRI. Results Case 1: 17 year-old, F, numbness of the right leg and arm, garbled speech and intense headache. MRI showed diffuse symmetric deep WM changes, unrestricted on DWI. Follow-up MRI 2 months later normal. Case 2: 12 year-old, F, right hand numbness, slurred speech, and pulsatile headache. MRI demonstrated WM foci of increased T2 and FLAIR signal in the left periventricular white matter and internal capsule, unrestricted on DWI. Follow-up MRI 4 months later showed resolution of previous lesions but new foci in the left occipital WM. Case 3: 10 year-old, M, acute confusion. MRI showed high T2 and FLAIR signal intensity in the deep and subcortical WM in the left occipital lobe, and smaller foci in the centrum semi ovale, all unrestricted on DWI. Last MRI showed complete resolution. Multiple diagnostic tests done in all excluded infection, vasculitis, demyelination, inherited arteriopathies and stroke-like disorders. Conclusion WMC in MRI can be seen in children with complex migraines. Pediatric Neuroradiologists should include this in their ddx of WMC, but it is mandatory the exclusion of other causes. 052 Multinational clinical evaluation of gadobenate dimeglumine in children referred for neurologic MR imaging Matthew J Kuhn, Emilio Cianciulli, Claudio Fonda, Mieczysaw Pasowicz, Pei-yi Gao Southern Illinois University
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Background Although widely used in adults, gadobenate dimeglumine has not been extensively tested for use in children with CNS disease. Objective To evaluate the safety and efficacy of gadobenate dimeglumine (Gd-BOPTA) in pediatric patients referred for neuro-MRI. Materials and methods Children 2–17 years were enrolled at 17 centers in USA, Europe, and China. Each subject received 0.1 mmol/kg Gd-BOPTA at 2 mL/s, followed by a saline flush. Safety assessments included adverse events (AE), vital signs, serial 12-lead ECG, and laboratory tests. Predose and postdose images were evaluated for lesion enhancement, border delineation, and visualization of internal morphology. Lesion-to-brain ratio (LBR) and contrast-to-noise ratio (CNR) were also measured. Results Ninety-two children (45 boys, 47 girls; mean age, 10.6 years) were enrolled and dosed (mean 8.4 mL). Eighty-nine children completed all safety evaluations (2–5 years, 13 pts; 6–10 years, 34 pts; 11–17 years, 45 pts). No clinically meaningful changes in vital signs, laboratory values, or ECGs were observed. Nine AE were reported in eight children (8.7%), including headache in two patients. Sixty subjects had tumors, of which 25 (41.7%) were benign and 35 (58.3%) were malignant. In children with enhancing lesions, Gd-BOPTA resulted in improved definition of disease extent, lesion border delineation, and visualization of lesion internal morphology. Three readers blinded to clinical history judged that Gd-BOPTA provided additional diagnostic information over predose images in 83.7–96.7% of all patients. Significant postdose increases in LBR (p<0.0001; mean change 0.9 to 1.1) and CNR (p<0.0016; mean change 49.9 to 74.6) were recorded. Conclusion Gadobenate dimeglumine is safe and efficacious for contrast-enhanced MRI of CNS lesions in children. 053 Multiple cerebral aneurysms and intracranial haemorrhage as complication of Aicardi–Goutieres syndrome (AGS) B Bernardi1, C Garone2, C Bortolotti3, C Sturiale3, A Stafa4, V Marchiani2, E Franzoni2 1. Pediatric Neuroradiology, Bologna, Italy 2. Child Neuropsychiatry Unit, Paediatric Dept. University of Bologna, Italy 3. Trauma and Emergency Neurosurgery Unit, Neuroscience Dept. Bologna, Italy 4. Neuroradiology Unit, Neuroscience Dept. Bologna, Italy Background Aicardi–Goutieres syndrome is a rare inherited encephalopathy whose clinical and radiological features mimic the sequelae of acquired in utero viral infections. Neuroimaging is characterized by intracranial calcifications variably involving deep grey matter, periventricular white matter and cerebellum, leukoencephalopathy, cortical atrophy, and microcephaly. We present an unusual case of multiple cerebral aneurysms and intracerebral hemorrhage in a 13year-old child with clinical and radiological findings of AGS Case report. A 13-year-old boy, with clinical history and neuroradiologic findings of AGS presented two episodes of acute vegetative symptoms, followed by lost of conscious. Neurological exam was
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unchanged compare to previous evaluations, showing tetraparesis with hyperreflexia, paratonia of limbs, truncal hypotonia, orobuccal and arm dystonia, microcephaly and strabismus. Few days later, due to appearance of rigor, headache, and increased right hypertonus, the patient was admitted to our Pediatric Emergency Department. CT and MRI confirmed brain calcifications and white matter abnormalities; in addition, a large right-sided temporal, subacute, intracerebral hematoma with intraventricular clots was noted. Four-vessel angiography showed two aneurysms of the right middle cerebral artery. In addition, a small right anterior cerebral artery aneurysm, was depicted. Diffuse arterial vasospasm was present. Discussion and conclusion Clinical/radiological findings and chronic cerebrospinal fluid lymphocytosis, characterizing AGS were early present in our full term patient. TORCH, other infective etiologies and metabolic diseases were excluded. When the child was 10-year-old, Reynaud disease started and recently leucocytoclastic vasculitis was discovered at skin biopsy. Childhood intracranial aneurysms are exceedingly uncommon in patients younger than 18 and to our knowledge, there are not previously report of cerebral bleeding from intracranial aneurysm in patient with AGS. We discuss possible relationship between AGS, peripheral vasculitis and cerebral aneurysms. AGS is a genetically heterogeneous disorder, genetic analysis to confirm clinical/radiological diagnosis and to define the specific mutation are in progress.
054 Value of a flowchart in diagnosis of pediatric cerebellar neoplasms for reviewers with different experience levels Korgun Koral, Betul Derinkuyu, Meltem Koral, Behroze Vaccha, Barjor Gimi, Lynn Gargan, Abdulnasser ElHajeri, Dave Roy, Daniel Bowers University of Texas Southwestern Medical Center Background A flowchart was created to facilitate diagnosis of common pediatric cerebellar tumors in a clinical setting. Objective To test the value of a flowchart in the diagnosis of pediatric cerebellar neoplasms in reviewers with different radiology experience. Materials and methods Review of neuro-oncology database in the last 9 years yielded 243 patients with tumors in the posterior fossa. Five common tumors [juvenile pilocytic astrocytoma (JPA), brainstem glioma, medulloblastoma, ependymoma and atypical teratoid/rhabdoid tumor (AT/RT)] comprised 88.4% of l posterior fossa neoplasms. Thirty-four brainstem gliomas were excluded. Patients with preoperative MRI (including DWI) available were included (M/F=48/20). The tumors were 24 medulloblastomas, 23 JPAs, 12 ependymomas and nine AT/RTs. Five reviewers evaluated the examinations. Two reviewers had no formal training in neuroradiology and were given a 10 min instruction. Two radiology residents with 3–4 years of training were given the same instruction. A second year neuroradiology fellow evaluated the scans without using the flowchart initially and using the flowchart subsequently.
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Results Reviewers with no clinical neuroradiology experience had an average of 75.7% correct pathological diagnosis. Radiology residents with 3–4 years training had an average of 76.3% correct diagnosis. The second year neuroradiology fellow made the correct diagnosis in 71.6% of tumors prior to instructions and in 77.3% following instruction about the flowchart. The chart improved the performance of the neuroradiology fellow 8.0%. With the usage of flowchart reviewers were able to make the diagnosis correctly in 88.9% of AT/RTs, in 82.6% of JPAs, in 73.9% of ependymomas and in 60% of medulloblastomas. Conclusion Following a short instruction on a simple flowchart regarding the diagnosis of most common pediatric cerebellar neoplasms, the performances of inexperienced and moderately experienced reviewers are similar to a more experienced reviewer.
Scientific Session 6: Genitouroniary
055 Sonographic characterization of pediatric nephropathies with proteinuria: Are there specific patterns? M Hackx, F Avni, K Ismaili, N Damry, K Vandenhout, M Hall Erasme Hospital Background The discovery of a proteinuria in children raises the suspicion of a nephrotic syndrome (NS). The spectrum of NS is wide and includes congenital, primary, syndromic and secondary origins. Objective The aims of this study were to determine (1) whether typical sonographic patterns can be demonstrated that may help to diagnose specific types of NS and (2) whether histology may help to understand these patterns. Materials and methods We have reviewed the sonographic characteristics of 16 patients (aged 3 days–10 years) with clinical evidence for chronic renal disease with proteinuria that underwent a renal biopsy between 2005 and 2008. The clinical, biological and genetic data, sonographic findings, histological appearances, final diagnosis and outcome were reviewed. The sonographic findings were classified in three groups: typical/specific for the disease, abnormal but not specific and normal Results Among the 16 cases, there were 14 cases of nephrotic syndromes (three NS of the Finnish type, three diffuse mesangial sclerosis, six focal and segmental hyalinosis, two “minimal changes”), one intertitial nephropathy and one IgA nephropathy. The sonographic appearances were typical in five (two Finnish types and three mesangial sclerosis), abnormal but non specific in five (one interstitial nephropathy, one IgA nephropathy, one minimal change, one hyalinosis and one Finnish type) and considered normal in six (five hyalinosis and one minimal change) Conclusion In case of a nephrotic syndrome, sonography can provide diagnostic patterns mainly in case of NS of the Finnish type and in case of diffuse mesangial sclerosis. In the other types of NS, the sonographic patterns observed are less specific or the examination may look normal; this usually parallels the importance of histological anomalies.
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056 Renal ultrasound screening of 5359 children after exposure to melamine tainted milk products in Hong Kong Winnie CW Chu, Stella S Ho, Hugh S Lam, Pak C Ng, KT Wong, William Wong, Dorothy FY Chan, Chi K Li, Anil T Ahuja The Chinese University of Hong Kong Background Since the first media reports in mid September 2008 linking an outbreak of renal disease (including renal stones and deaths) among children on the mainland of China to consumption of milk products contaminated with melamine, screening programs were launched nationwide. A similar program was also initiated in Hong Kong Special Administrative Region. Objective To document sonograhic findings of children underwent screening at the Prince of Wales Hospital, one of the designated Special Assessment Centers in Hong Kong, between the periods 28 September 2008 to 9 January 2009. Materials and methods Children who were aged 12 years or less and had consumed melamine tainted milk products daily for one month or more were referred for ultrasound screening of both kidneys and bladder. Results Five thousand three hundred fifty-nine children (2,919 boys, 2,439 girls, mean age 6), all asymptomatic, were reviewed. Only one child was found to have a non-obstructive 7 mm renal stone. One child had increased echogenicity in both renal papillae. Twelve children were found to have small hyperechoic renal foci (<4 mm in diameter) near the renal papillae, associated with comet-tail artifacts on gray scale sonography and twinkling artifact on color Doppler. Thirty-nine children were identified with positive sonographic findings, considered as incidental and unlikely pertaining to melamine intake. These included three duplex kidneys, 11 pelviectasia, three cortical milk of calcium cysts, three unilateral renal agenesis, eight polycystic or simple cystic kidney disease, four horseshoe kidneys, one transient dilatation of ureter, one ureterocele, two scarred kidneys and three ovarian lesions. Conclusion Our findings should reassure regions outside the mainland of China that renal stones and obstructive hydronephrosis are not adverse features in populations with exposure to milk products of low dose melamine (similar dose as Hong Kong). The nature and significance of hyperechoic foci in some children however warrant further clinical follow up. 057 Ureteric jet Doppler waveform: is it a reliable predictor of vesicoureteric reflux in children D Kljucevsek1, T Kljucevsek2, T Kersnik Levart3, RB Kenda3 1. Children’s Hospital, Paediatric Radiology Unit, University Medical Centre, Ljubljana, Slovenia 2. Clinical Institute for Radiology, University Medical Centre, Ljubljana, Slovenia 3. Children’s Hospital, Department Of Paediatric Nephrology, University Medical Centre, Ljubljana, Slovenia
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Background The progress of diagnostics particular in pediatrics is directed towards finding diagnostic procedures that are less harmful and burdensome for patients, but that at the same time they ensure enough information for further decisions if more invasive diagnostic procedures are necessary or not. Objective The purpose of our prospective study was to evaluate the sensitivity and specificity of a ureteric jet Doppler waveform (UJDW) in identifying patients with vesicoureteric reflux (VUR) compared with the established direct method of echo enhanced voiding urosonography (VUS). Materials and methods Among 75 children (57 girls and 18 boys, aged 3 to 12 years, mean 4.82 years) who were admitted for echo enhanced VUS either as a part of a follow-up of previously detected VUR or after proven urinary tract infections, UJDW was successfully performed in 70 children. The procedure was considered as successful if at least 10 UJDW measurements from each ureteric unit were detected. Than the sequences of UJDW per ureteric unit was determined and were classified into three groups: monophasic—suggestive of VUR, complex—not suggestive of VUR and mixed sequence—suggestive of VUR when a certain ratio between monophasic and complex UJDWs was achieved. Sensitivity and specificity of UJDW measurement compared with echo enhanced VUS were calculated. Results Sensitivity of UJDW in patients was 90%, specificity 82%. This means that on the basis of the results of UJDW measurement 61.5% of children would not need a more invasive procedure. Conclusion The present study has shown that, compared to echo enhanced VUS, the measurement of UJDW seems to be sensitive enough to detect VUR in children older than 3 years and can be proposed as screening method. Only those children with findings suggestive of VUR should be investigated further with one of the more invasive direct methods. 058 Hypervascular Wilms tumor on imaging: beware acquired von Willebrand syndrome PA Taylor, PA Baxter, M Chintagumpala, JG Nuchtern, DH Mahoney, J Teruya, DL Yee, RP Guillerman Phoebe Putney Memorial Hospital, Texas Childrens Hospital (TCH) Objective To report the association of marked hypervascularity of Wilms tumor (WT) on preoperative imaging with acquired von Willebrand syndrome (aVWS) and risk of severe bleeding with invasive procedures. Materials and methods A retrospective review of the imaging studies and clinical charts of 97 consecutive children with WT treated at our institution from 1999–2007 yielded 80 children who had obtained CT exams at the time of diagnosis that were available for review. The presence of aVWS was established by coagulation tests revealing diminished von Willebrand factor activity, antigen, and high molecular weight multimer levels. Tumor hypervascularity was determined subjectively by the recognition of multiple enlarged intratumoral vessels compared to normal kidney or recruitment of extrarenal systemic vessels by the tumor.
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Results Marked Wilms tumor hypervascularity on CT in association with aVWS and severe bleeding during surgery for tumor resection was noted in two of the 80 patients, while marked tumor hypervascularity without clinically overt aVWS was noted in six of the 80 patients. By 2×2 table contingency analysis, the diagnostic performance characteristics of marked tumor hypervascularity on CT for aVWS-WT and severe bleeding is: sensitivity 100%, specificity 92%, accuracy 92%, positive predictive value 25%, negative predictive value 100%, positive likelihood ratio 13, and negative likelihood ratio 0. Conclusion Although statistical analysis is limited by the small number of AVWS-WT cases, the data suggest that CT imaging can reliably detect children with aVWS-WT at risk of severe bleeding, and the finding of marked renal tumor hypervascularity should prompt testing for aVWS and appropriate treatment prior to surgery to mitigate hemorrhagic complications. Possible mechanisms of aVWS-WT include elevated hyaluronic acid levels or high shear forces in the abnormal tumor vasculature causing adsorption of VWF multimers onto platelets. 059 MR urography (MRU) in children: simplifying the functional analysis Dmitry Khrichenko, Kassa Darge Dept. of Radiology, CHOP Background The functional analysis part of MR urography (MRU) requires post-processing on an external workstation using complicated and not user friendly programs. The latter has become a major drawback to the widespread application of functional MRU in children. Objective Our aim is to present a semi-automated program for MRU functional analysis that has the potential to overcome this impediment. Materials and methods The program was developed in a pediatric radiology department using Interactive Data Language (IDL) on 32 bit Windows and Linux systems. A widget user interface was created for real-time image analysis. The data is loaded in DICOM format and is stored as a 4D integer array. A powerful set of algorithms was developed to accurately segment the parenchyma. This requires the user only to mark grossly the aorta and the kidneys on one image. An automatic segmentation of each is generated in seconds. The Patlak model is used to assess renal function. Results Enhancement curves of the aorta and both kidneys, including each moiety in a duplex system, are generated. Patlak ratio plots are created for those regions. Signal intensity and functional histograms are made available. Parametric maps based on the Patlak model can be displayed in color for visual functional assessment. Other results that are automatically generated are differential renal functions per volume and Patlak, calyceal and renal transit times and time-to-peak. All graphics can be exported in multiple formats including JPEGs and excel sheets. Conclusion A simple user-friendly, semi-automated program for MRU is available that can be used by technologists and radiologists to easily generate comprehensive functional data. This may give rise to more impetus to use functional MRU in children.
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060 Ureteropelvic junction obstruction in children due to fibroepithelial polyps Kassa Darge, Pasquale Casale Dept. of Radiology, CHOP Background Fibroepithelial polyps (FEPs) are uncommon in children and difficult to diagnose preoperatively. They frequently present as UPJ obstruction. The diagnosis of FEPs is regularly made at pyeloplasty. With the availability of ureteroscopic laser ablation the preoperative diagnosis of FEPs would alter the urological management. Objective The aim of this study was to evaluate the imaging studies of patients treated by laser ablation for FEPs and identify the diagnostic difficulties and point out potential changes in future imaging strategies. Materials and methods Over a period of 4 years nine patients (seven boys, two girls; 5–18 years) were found to have at pyeloplasty FEPs as the cause of their UPJ obstruction. All of them underwent additional ureteroscopic laser ablation. The imaging studies were retrospectively analyzed with the knowledge of the operative result. Results The initial imaging modality was US in eight patients and excretory urography in one. Further imaging included MR urography (MRU; n = 2) and CT (n = 1). The images from intraoperative retrograde pyelography were available in 6 patients. Pelvicalyceal dilatation was present in all suggesting the diagnosis of UPJ obstruction. No diagnosis of FEP was made preoperatively. The right and left kidneys were involved in four and five cases, respectively. Concomitant renal stones were found in two patients. In retrospect FEPs could only be identified in three patients (US=2, MRU=1). The finding in the MRU was the most conspicuous one. Conclusion Increase in the preoperative diagnosis of FEPs in the presence of UPJ obstruction may potentially be achieved by: (1) more consideration of FEPs as potential causes (2) targeted highresolution US of the renal pelvis and proximal ureter (3) utilization of MRU incorporating high-resolution and cine sequences. Due to changing urologic management strategy more effort should be made to make the diagnosis preoperatively. 061 Specificity of ipsilateral uterine deviation in adnexal torsion Jenna Harmon, Larry Binkovitz and Julie Stephens Nationwide Childrens Hospital Background The imaging diagnosis of adnexal torsion is difficult; many adnexal lesions have similar appearances. Ipsilateral uterine deviation, IUD, (towards the side of adnexal abnormality) has been suggested to be specific for torsion. Objective To investigate the sensitivity and specificity of IUD as a marker for adnexal torsion. Materials and methods We retrospectively reviewed the pelvic ultrasounds of all females under the age of 22 years who were imaged at Nationwide Children’s Hospital in 2007 and compared uterine
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position in girls with normal US (n=297), adnexal masses (n=47) to those with adnexal torsion between 1995 and 2007 (n=44). Results Uterine deviation was more common and more severe in patients with adnexal torsion than in patients with normal adnexal (p<0.001) or with adnexal mass lesions of other etiologies (p= 0.010). IUD was more frequent with torsions than other adnexal lesions (p<0.001). The sensitivity and specificity of IUD for adnexal torsion were 41% and 98%, respectively. The majority of adnexal torsions demonstrated a midline uterus (21/44, 48%) or contralateral deviation (5/44, 11%). Conclusion IUD is common in torsion and rare in other causes of adnexal masses but it cannot be considered a sensitive or specific marker for adnexal torsion.
Scientific Session 7: Musculoskeletal
062 Carpal “erosions” in children with juvenile idiopathic arthritis: MRI vs. radiography Rikin Hargunani, Øystein E Olsen, Patricia Woo, Clarissa Pilkington, Rod Jones, Amaka Offiah, Catherine Owens, Karen Rosendahl Great Ormond Street Hospital for Children, London Objective To compare MRI and radiographs in the assessment of carpal depressions in children with JIA, and to determine whether these represent destructive change or normal variation. Materials and methods Ten radiographs and MRI’s obtained on the same day in patients included in an ongoing multi centre study on JIA were analysed. We registered all bone depressions as either focal or tubular on MRI (3DT1SE weighted sequence) for each of five carpal bones. The radiographs were scored by the same observer in a blinded design. To assess whether the depressions were likely to represent erosions or not, we registered, in a later session, whether there was associated inflammatory (effusion and or pathological synovial enhancement and/or surrounding bone oedema on MRI) or destructive (reduced joint space on radiographs) change. Results Fifty carpal bones in ten patients (four males) with a median age of 13 years 9 months (range 5–16 years) were included. MRI demonstrated a total of 26 focal and 41 tubular depressions, of which nine were seen radiographically in each group. Only three depressions were seen on radiographs alone. Of the 67 depressions seen on MRI, 15 of the 26 (58%) focal and nine of the 41 (22%) tubular depressions were associated with inflammatory change on MRI and/or destructive change on radiographs, consistent with JIA, while seven (27%) focal and 27 (66%) tubular depressions contained a vessel. For nine depressions (13%), four focal and five tubular, no explanation was found. Of the 21 depressions seen radiographically, ten (47.6%) had associated findings suggestive of JIA, while seven (33%) contained vessels. Conclusion MRI showed 67 carpal depressions, of which a quarter was visible radiographically. For both modalities, only 40–50% of
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the depressions were likely to represent destructive erosions. We suggest that the remainder most likely represent normal variation, including vascular channels. 063 Cartilaginous change in JIA: a new ultrasound finding Rikin Hargunani, Catherine Owens, Karen Rosendahl Great Ormond Street Hospital for Children, London Objective To illustrate a novel finding in the deep cartilage of patients with Juvenile Rheumatoid Arthritis, as demonstrated by ultrasound. Materials and methods During a large multi-centre study on JIA, including plain radiographs, ultrasound and MRI of the wrist or of the hip joints, we observed hyperechoic changes in deep cartilage in five patients during high frequency ultrasound examination. Results Although thinning of the hyaline articular cartilage is widely recognised in established JIA, this novel sonographic appearance is believed to represent an early manifestation of the disease in deep cartilage and has never previously been described. An illustration of the findings is presented together with a review of the likely pathogenesis. Conclusion This novel finding is thought to represent evidence of early cartilage damage and its recognition, when present, may facilitate radiological diagnosis of the earliest manifestations of the disease. 064 Juvenile dermatomyositis: a review of presenting MRI findings and correlation with clinical outcome data Patricia E Ladd, Kathleen H Emery, Daniel J Lovell, Tal Laor, Shelia R Salisbury, Kevin E Bove Cincinnati Childrens Hospital Background The clinical course of dermatomyositis can be extremely variable between patients and is categorized into limited, chronic, and chronic ulcerative disease. The latter two groups often require more aggressive treatment than standard steroid therapy. Pathology studies have correlated histologic features with clinical outcome, but to date there have been no reported MRI studies to assess features that may correlate with outcome. Objective To review presenting findings of dermatomyositis on initial MRI of the pelvis and thighs and to assess if any MRI findings predict the clinical course. Materials and methods Forty-five patients (31 female, 14 male) with pathologic and clinical diagnosis of dermatomyositis with at least 14 months of follow-up were included. The initial MRI studies of the pelvis and thighs prior to institution of therapy were retrospectively reviewed in blinded fashion. MRI findings included increased T2 signal abnormalities in muscle, fat, and fascia. Involved muscle compartments were noted. These findings were independently correlated with clinical outcome. Results Presentations ranged from florid increased T2 muscle signal with enhancement in all compartments (ten patients) to
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normal (three patients), with the anterior compartment of the thigh the most frequent site. Extent of muscle involvement and presence of fascial involvement did not correlate with disease outcome. Linear decreased T1 and increased T2 signal in the subcutaneous fat were seen in nine of 23 patients with chronic or chronic ulcerative disease and only two in 22 with limited disease (sensitivity 39%, specificity 91%, NPV 59%, PPV 82%). Conclusion Most MRI findings cannot predict disease course in pediatric patients with newly diagnosed juvenile dermatomyositis. However, abnormal subcutaneous fat signal though seen in a minority of patients appears to have a high specificity for predicting a more aggressive disease course. 065 Diagnosis of rigid spine muscular dystrophies: the role of MRI E Mercuri1,2, E Clement1, AC Offiah1, A Pichiecchio2, M Rutherford3,G Vasco2, F Muntoni1 1. Great Ormond Street Hospital for Children 2. Catholic University, Rome 3. Imperial College London Background There is considerable overlap in the congenital muscular dystrophies (CMD) presenting clinically with a rigid spine. Genetic confirmation is available, but is time consuming, relatively expensive and is not always positive. There is accumulating evidence that muscle MRI may play an important role in identifying these genetically different conditions. Objective To evaluate the sensitivity and specificity of T1 weighted axial thigh and calf muscle MRI in differentiating SEPN1, Bethlem, Ullrich, autosomal dominant Emery Dreifuss and calpain deficient limb girdle muscular dystrophies. Materials and methods We performed a retrospective review of MRI images. Patients were included if they had genetic confirmation of one of the five dystrophies listed above and had undergone at least one muscle MRI scan. Three neurologists, one neuroradiologist and one paediatric musculoskeletal radiologist reviewed all scans, providing both independent and consensus opinions. Patients’ MRIs were compared to published data for the various conditions, and classified as typical; consistent but with other changes; different; or uninformative. Observers were blinded to results of genetic tests. Results Sixty-six of 83 (80%) scans classified as typical and seven of 83 scans (8%) classified as consistent with a condition concurred with clinical and genetic tests. Less than 10% of scans were uninformative due to very mild or normal findings. In one case (1%) the scan was classified as typical of a collagen VI mutation—this patient in fact had a calpainopathy. For all groups, MRI had a sensitivity of 75% (ranging from 46% for Emery Dreifuss to 100% for Ullrich CMD). Four of the five observers concurred 100% of the time; one observer disagreed with the others on two occasions. Conclusion Muscle MRI provides a simple, rapid, sensitive and specific method of differentiating various types of rigid spine CMD, and therefore is potentially a useful adjunct in cases where the clinical diagnosis is uncertain.
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066 The effect of growth on the medial collateral ligament (MCL) and medial femoral condyle (MFC) of the knee Patricia E Ladd, Tal Laor, Kathleen H Emery, Shelia R Salisbury Cincinnati Childrens Hospital Background Children are undergoing knee reconstructive surgery at earlier ages, which requires an understanding of the effects of growth more than ever before. The medial patellofemoral ligament (MPFL), the largest component of the medial soft tissue restraints of the patella, is frequently injured in patellar dislocations and younger patients are requiring reconstructive grafts. The medial collateral ligament (MCL) origin is used as a landmark during surgery for approximating the location of the femoral attachment of the MPFL. However, little is known about the effects of epiphyseal growth on the position of the MCL relative to the distal femoral physis. Objective To compile normative data for the origin of the MCL and its relationship to the distal femur and physis for both genders during growth. Materials and methods In 300 knee MRIs (143 boys, 157 girls; ages 0–20 years), the distance of the origin of the MCL from the distal femoral physis and height of the ipsilateral medial femoral condyle (MFC) were measured. The MCL origin/MFC ratio on coronal images was calculated to identify the relationship of the MCL origin site to the physis. Values were correlated with patient age, gender, and physeal patency. Results The MCL origin distance to the physis increases by 0.1 mm/year while the physis is patent. The height of the MFC increases by 1.3 mm (girls) and 1.5 mm (boys)/year. Therefore, the MCL origin/MFC ratio decreases with age (p<0.0001). The ratio differs between genders (p<0.05) during physeal patency, and remains stable after physeal fusion. Conclusion During growth, the MCL origin moves distally from the femoral physis. The condyle height increases more rapidly. This pattern likely reflects the hemispherical growth of the distal femoral epiphysis. Recognition of this normal developmental relationship might be useful for planning reparative surgery in growing children. 067 Subcutaneous annular granuloma—a differential diagnosis not to forget in expansive lower leg soft tissues lesions of young children T Riebel, I Scheer Ped. Radiology, Charité-Universitätsmedizin Berlin Background The spectrum of lower leg lesions in children covers numerous, including malignant entities with either primary origin in the soft-tissues or expanding from the bone. Objective Own observations of a rare pseudotumorous expansive soft-tissues disease is presented, which has to be kept in mind in the differential diagnosis of such lower leg lesions to prevent unnecessary biopsy and too much imaging. Materials and methods The imaging material (sonograms in all, radiograms and MRI in the first three patients) and the clinical
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charts of six children (four female, two male; aged 28–65 months) seen at our hospital within 2 years with a local lower leg softtissues swelling were analyzed retrospectively. Results All lesions were pretibial, firm, indolent, non-movable, and without inflammatory signs. They had developed spontaneously and persisted over up to 5 months without further increase. Laboratory tests were all negative. Imaging findings were identical in all cases: The lesions were located near to the bony surface with diameters up to 3.5 cm and no calcifications. On ultrasound they were homogeneously echopoor with indistinct borders and only little increased perfusion. On MRI they presented with low signal in T1, high in T2 and marked contrast enhancement. No intraosseous changes could be found. Histological proof was done in only the first two patients. Because of an identical clinical and sonographic initial presentation, additional imaging as well as biopsy were dispensed in the later patients, in whom the clinical course under only sonographic controls was as expected, then. Conclusion When dealing with expansive lower leg soft-tissues lesions in young children, the combination of the presented typical clinical and imaging findings should give rise not to forget the entity of pseudorheumatoid subcutaneous annular granuloma and to follow those patients primarily with only ultrasound controls. 068 Whole body MRI in infantile hypophosphatasia—imaging characteristics in 3 cases M Stenzel, C Beck, H Girschick, M Beer University Hospital Würzburg Background Hypophosphatasia is caused by mutations of the TNSALP gene and results in impaired bone formation and dentition. Objective Skeletal changes in hypophosphatasia are well documented only with X-ray imaging. As it is crucial to draw a line between bony changes related to the primary disease, for example bowing of the long bones, and secondary changes, like fractures and pseudofractures, MR imaging features of the disease should be known. Materials and methods Two readers reviewed whole body MRI scans in three children (2, 4 and 8 years old), all with genetically proven hypophosphatasia. Analysis was made by consensus. The following criteria were looked at in bones: (1) signal changes in two non-enhanced sequences (TIRM, TSE T1w) and post gadolinium scans (TSE T1w, fat saturated), (2) distribution of signal changes, (3) location in long bones, (4) bowing of bones, (5) Bowdler spurs. Besides the bony changes the authors checked for craniocervical abnormalities. Results The whole body MRI examinations of all three patients were of very good quality allowing proper readability. The most obvious changes in all patients were found in the metaphysis suggesting structural changes with edema and pronounced contrast enhancement. The contours of the metaphyses were irregular, as might be expected from X-ray imaging. Epiphyseal signal changes were detected in only one patient. Long bone bowing occurred in all patients, whereas Bowdler spurs were absent in all patients. A mild cerebellar herniation was found in one child.
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Conclusion Knowledge of signal changes, their distribution and extent in whole body MRI allows for proper evaluation of cases of infantile hypophosphatasia in cases where secondary changes have to be excluded. 069 The relationship between ultrasonographic findings and the pain during activity in Osgood Schlatter syndrome Zeynep Erhuner1, Ugur Toprak1, Derya Ozer2, Gul Baltaci2, Sevinc Bostanoglu1, Mehmet Alp Karademir1 1. Ankara Numune Training and Research Hospital 2. Hacettepe University School of Physiotherapy and Rehabilitation, Sports Physiotherapy Unit Background Osgood Schlatter syndrome is characterized by sensitivity of the tuberosity of tibia, swelling, pain in 8–15 yearold children. Symptoms worsen with the activities which include jumping (basketball, volleyball etc.) or direct knee contact. Objective We aimed to investigate whether there is a correlation between the diameter and area of the patellar tendon and the pain. Materials and methods The study group consisted of 36 children; five girls, 31 boys. Their average age was 14. These subjects with unilateral involvement were clinically examined and their pain was evaluated by visual pain scala (VPS) during rest, activity, squatting and kneeling. Sonographic examination was performed afterwards. The diameter and distal part area of the patellar tendon at the point of distal adhesion was measured. Tibial tubercle apophysis was evaluated in addition. The findings were classified according to the Flaviis classification. Results VPS pain score is 0.4 at rest, 2.7 with activity, 3.1 with squatting and 3.8 with kneeling on average. According to the Flaviis classification, ten subjects were type I, nine were type II, eight were type III and nine were classified as type IV. Types and activity pain were related (p<0.05, r=0.34). There was also a relation between the diameter and area of the tendon and activity pain (p<0.05, r=0.38 for diameter, r=0.35 for area). However, other functional pain forms and sonographic findings were not related. Conclusion Activity pain increases directly proportional to the thickness of the tendon. The relation of Flaviis classification, which is arranged according to the tendon thickness and the level of tissue involvement around the tendon, with activity pain indicate that sonographic and clinical findings run together. Thus, we consider that the follow-up of these children can be made with sonography in a reliable way. 070 Assessment of power Doppler in the diagnosis of Osgood Schlatter syndrome G Ananthakrishnan, TF Beattie, AG Wilkinson Royal Hospital for Sick Children, Edinburgh, UK Background Osgood Schlatter syndrome (OSS) presents in children and adolescents with local pain, swelling and tenderness of the tibial tuberosity and is thought to result from a repetitive avulsive force by the patellar tendon. Although radiography and MRI can be used to
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diagnose the condition, ultrasound is cheap, quick, readily available and avoids radiation. Sonography may demonstrate soft tissue swelling, effusion, and thickening of the patellar tendon, but the use of Doppler ultrasound has not been reported. Objective To evaluate power Doppler as a first line investigation in patients with clinical suspicion of Osgood Schlatter syndrome. Materials and methods Patients presenting to the emergency department with a clinical suspicion of Osgood Schlatter’s disease underwent ultrasound examination of both knees. A high frequency linear-array probe was used (Siemens Antares). Parameters recorded included thickness and echogenicity of the distal patellar tendon, comparative vascularity on power Doppler, presence of effusion, and fragmentation of the apophysis. Results Fourteen patients with ages ranging from 10–14 years (mean −11.9) were examined in a period of 21 months. Twelve cases were unilateral and 2 bilateral. In all cases, significantly increased flow was noted in the distal patellar tendon or its insertion compared to the asymptomatic side unless symptoms were bilateral. In 11 patients, the affected tendon was thicker by up to 2.3 mm (mean 1 mm). Fragmentation of the tibial tuberosity was noted in three cases. No effusion was identified in any of the cases. Conclusion This is the first report of the use of power Doppler in OSS. It allows accurate diagnosis even in the absence of other signs such as significant difference in thickness or echogenicity of the patellar tendon or fragmentation of the tibial tuberosity. 071 Use of the axial oblique method for femoral anteversion assessment Delma Jarrett, Amy Oliveira, Paul Mitchell, Brian Snyder, Paul Kleinman Children’s Hospital Boston Background Femoral anteversion measurements performed from axial CT slices through the femoral neck are suboptimal as the entire femoral neck is not imaged on a single slice and measurements are affected by patient positioning. With helical CT, axial images can be reformatted along the long axis of the femoral neck. Objective Compare anteversion measurement techniques employing axial oblique reformations to traditional assessments using axial CT and thick axial and axial oblique MIPS. Materials and methods A cadaveric femur with known femoral anteversion of 14° was scanned using multislice CT. Using postprocessing software, images were reformatted to simulate 0–40° of flexion, extension, internal and external rotation in 10 degree increments. Two readers performed three sets of anteversion measurements on the femur in each simulated position, using five methods: (1) an axial slice through the neck, (2) multiple axial images to obtain the head-trochanter angle, (3) 3 cm thick axial MIP through the femoral neck, (4) an axial oblique image along the long axis of the femoral neck, (5) 3 cm axial oblique MIP image through the femoral neck. Accuracy and variability for each method was assessed. Results The mean ± SD anteversion measurement of methods were (in degrees) 16.4±10.7, 16.7±6.7, 14.9±9.5, 17.5±2.5, and 16.6± 1.9. Axial MIP images gave the most accurate results, but had the highest intra-rater variability across the range of positions. Intrarater variability was smallest for methods 5 (1.4) and 4 (2.1), and
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progressively larger for methods 2 (3.0), 3 (4.3) and 1 (4.5). Interrater variability was small for all methods Conclusion Axial CT anteversion measurements show unacceptable variability that is overcome by employing axial oblique reformats which can be easily incorporated into routine femoral anteversion protocols. 072 Pediatric orthopedic applications for O-arm intraoperative imaging: are ALARA principles being followed? Anjum Bandarkar, Dorothy Bulas, Tom Fearon, Laurel Blakemore, Patrick Kaszubski Childrens National Medical Center, George Washington University Medical Center Washington DC Background O-arm is a cone beam portable imaging system designed to provide 3D imaging and navigation tracking in the OR. Pediatric applications and radiation dose per exam have not been established. Objective To review pediatric applications using this technology and assess relative radiation dose exposure. Materials and methods O-arm was used in 52 cases from March 2007 to September 2008. Ages ranged from 2 months–16 years. Studies were reviewed for indication, technique, and change in management. Relative radiation dose was estimated using ionizing chamber calculations Results Indications included hip dysplasia (34), scoliosis (ten), C-spine fusion (four), bone cyst/mass (three), Sprengel’s deformity (one). Technique included 25, 32, or 40 mA, 120 KVp, 0.83 mm thickness, 80–192 rotations per scan. Image quality was fair to excellent for all studies. Number of scans per OR case—five in two cases, four in two cases, three in two cases, two in seven cases, one in 39 cases. Three-dimensional imaging was useful in assessing pin trajectory, hip position, and reviewing results prior to leaving the OR. Limitations include bulky size of equipment, time required to position the system, limited collimation and field of view options. Dosimetry comparison was performed using the method of Dixon et al. The normalized equilibrium radiation dose estimate was.45 rad/100 mAs body phantom O-arm vs.53 rad/100 mAs helical CT pitch 1.5, 10 mm and.94 rad/100 mAs head phantom O-arm vs 1.65 rad/100 mAs, axial CT, 10 mm. Conclusion O-arm technology provides portable 3D CT images immediately helping guide complex orthopedic surgical cases. The relative radiation dose estimate for each scan, however, can be as high as a typical abdominal CT scan. Orthopedic surgeons should be aware of these dose issues and follow ALARA principles when using this technology. 073 Child abuse vs. rickets—controversy and contribution Alan E Oestreich Cincinnati Children’s Hospital Medical Center Background KA Keller and PD Barnes have published, in Pediatric Radiology [38:1210–6], cases radiographically strongly
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suggestive of child abuse; but the authors imply that rickets could account for the fractures. Other authors in the same journal issue question their conclusions and implications. Objective To review well-established criteria for the diagnosis of rickets including findings not mentioned in the article or its rebuttals. To suggest an appropriate approach of pediatric radiologists in the face of the controversy. Materials and methods Review of a career-long experience with details of radiologic rickets diagnosis, including changes at the collar of Laval–Jeantet not mentioned in the articles under consideration. Review also of the (different) imaging findings in abuse at the same region of bone. Results In the four cases of the article, in none is the metaphyseal collar of Laval–Jeantet absent or shortened. Cupping of the distal ulna margin is a normal finding. The illustrations of the cases show many well-established findings reported in child abuse. Both abuse fractures and rickets (and secondary hyperparathyroidism) affect metaphyses including the anterior ends of ossified ribs, but the finding are different in the two conditions. Fractures do often occur in babies with secondary hyperparathyroidism, but radiographic findings of that condition are required for such a diagnosis. Conclusion Rickets is a radiographic diagnosis. Imitators of child abuse on X-ray are numerous, but rickets without radiographic evidence is not one of them. The question of vitamin D levels and the question of child abuse should not be confounded. 074 A study of the patterns of humeral fractures and the probability of physical abuse in children S Harave, C Landes Alder Hey Children’s Hospital Background Fractures of long bones are a common finding in nonaccidental injury. It is important to be able to differentiate these (abusive) injuries from those that result from accidental trauma. A recent systematic review of the published studies revealed that a child under 3 years of age with a humeral fracture has a one in two chance of having been abused. Objective (1) To evaluate the outcome of children less than 3 years of age, who presented with suspected humeral fracture. (2) To assess the likelihood that a humeral fracture is the result of physical abuse. Materials and methods A retrospective review of all the successive plain radiographs performed for suspected humeral fractures in children under three in a large tertiary children hospital in the UK. Review of the case notes if necessary to confirm the final outcome. Results From 2007 (June) to 2009 (January) (19 months), a total 95 patients had 98 humeral X-rays taken. Twenty-four of these were abnormal (fracture seen). Four were confirmed to be non accidental in nature and the outcome of three patients is awaited. Five of the six children under the age of 1 month had birth related injury. All traumatic fractures were distal humeral and mostly supracondylar.
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Conclusion Non accidental injury is a serious possibility in children who present with a humeral fracture. However, our study shows that this is heavily influenced by the age and developmental stage of the child at presentation, the type of fracture and the presence or absence of appropriate history of trauma. 075 Femoral neck irregularities in 18-year-olds—a common finding: preliminary results Lene Bjerke Laborie 1,3 , Trude G Lehmann 2,3 , Ingvild Engesæter2,3, Deborah Eastwood4, Lars B Engesæter2,3, Karen Rosendahl3,4 1. Dept. of Radiology, Haukeland University Hospital, 5021 Bergen, Norway 2. Dept. of Orthopaedics, Haukeland University Hospital, 5021 Bergen, Norway 3. Institute of Surgical Sciences, University of Bergen, 5021 Bergen, Norway 4. Department of Radiology, Great Ormond Street Hospital for Children, London, WC1N 3JH, UK Background Femoral neck irregularities as demonstrated radiographically are believed to represent acetabular impingement causing hip pain and discomfort. During a large, population based clinical and radiological follow-up of the 1989 Bergen Birth Cohort, we noticed that femoral neck irregularities were a relative common radiographic finding. Objective Examine whether such defects were associated with hip pain as assessed on clinical examination. Materials and methods The 1989 birth cohort (n=5,020) was invited to participate in a large follow-up including clinical examination and radiographs of the hips, and to answer a questionnaire on quality of life and hip problems (EQ-5D, Womac). Two radiographs were obtained according to a standardised protocol, one AP and one frog leg view, using low-dose DR-technique. Irregularities were defined as either a lytic defect or a hump to the femoral neck demonstrated on the AP and/or frog leg views. The clinical examinations performed by one of four physicians included assessment of hip ab/adduction, internal/ external rotation and a test for anterior impingement, amongst others. Associations between clinical and radiographic findings were examined using chi-squared tests, and a p-value (two-sided) <0.05 was considered statistically significant. Results To date, the radiographs from 397 healthy 18-year-olds have been analysed. Femoral neck irregularities were seen in 70 out of 794 hips (8.8%; 33 were right sided and 37 left sided). Thirty-six (51.4%) of these were located on the “anterolateral”, aspect of the femoral neck, while 19 (27.1%) were anterior and 19 (27.1%) were lateral. There was no association between a femoral neck irregularity and a positive impingement test (p=0.18). Conclusion Irregularities of the femoral neck is a common finding in healthy adolescents, and do not appear to be associated with hip pain as assessed by a test for anterior impingement.
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Scientific Session 8: Cardiac
076 Dual source ECG gated cardiac studies in neonates Carolyn Young, Catherine Owens, Andrew Taylor Great Ormond Street Hospital for Children NHS Trust Objective To demonstrate that ECG gated studies in children with high heart rate can provide good image resolution without the anticipated increase in radiation dose. Materials and methods Comparison of 20 gated (dual source) and 22 non-gated (single source) cardiac studies. Assessment made of (1) radiation dose (CT EXPO normalised to weight and sex); (2) image noise and image sharpness (measured as the slope of density change at the left ventricular-septal interface, higher angle represent sharper image). Dose modulation (care dose 4D) was used in both studies with further minimisation of radiation dose for gated studies by the reduction of kVp from 100 to 80 with corresponding increase in mAs to maintain image resolution and the use of prospective ECG triggered pulsing limiting the radiation output to 4% during the systolic phase. Results Patient age range between 2 weeks and 15 months. The mean heart rate for gated study was 126±22 bpm (range 103–172) with effective dose of 1.7±0.8 mSv and 2.6±1 mSv (p=0.003), for non gated study. Image noise was 37±7.8 HU and 17±3.6 HU (p<0.001) for gated and non-gated studies and image sharpness was 82°±2.8° and 68°±11° (p<0.001) respectively. Conclusion Allowing for differences in scanning parameters, reconstruction slice thickness and algorithm, the noise level was lower for non-gated studies but with reduced image sharpness, this improved with gated studies even at high heart rates. Radiation dose was kept low with appropriate adaptation of scanning parameters. 077 Pulmonary hypertension in paediatrics Carolyn Young, Catherine Owens, Andrew Taylor Great Ormond Street Hospital for Children NHS Trust Objective To demonstrate the range of anatomical anomalies associated with pulmonary hypertension as presented on CT findings. Materials and methods Assessment of 65 case reports in children (age range 1 month–18 years) investigated for known or suspected PH and pulmonary abnormalities. CT appearances of right ventricular hypertrophy, pulmonary artery size, pulmonary vein stenoses, and lung parenchyma were defined. Results In five patients, the CT appearance was defined as normal. Mild to severe main pulmonary artery dilatation (mean 2.5± 0.9 cm) was observed in remaining 60 patients. Thrombus was seen in the pulmonary arteries in two of 60 cases with abnormal arborisation, branching pattern and pruning of peripheral vessel seen in 25/60 cases. Right ventricular hypertrophy was seen in 33/
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60 cases and right atrial dilatation in seven cases. Left ventricular hypertrophy seen in two of 60 patients and in six of 60 cases the ventricular cavities were considered small. Small systemic collateral vessels arising from the aorta supplying the pulmonary bed were seen in ten of 60 cases. Abnormal pulmonary venous drainage was seen in four of 60 cases. Patchy mosaic attenuation was detected in 22/60; ground glass appearance in eight of 60 and four of 60 had interstitial changes. Bronchial compression was seen in 12 cases. Other findings included five ASD, four VSD, four right-sided aortic arch and two hypoplastic aorta. Conclusion A wide range of CT findings was recognised in patients presented with PH. Assessment of the heart, great vessels and lung parenchyma is necessary to fully characterise these patients. This information may help guide treatment options for the patients. 078 Radiation dose management in pediatric cardiac CTA: a quality improvement study SJ Westra, M Kalra, B Liu, S Abbara Massachusetts General Hospital, Boston, USA Background Cardiac CTA is a powerful fast technique to image congenital heart disease, but its high radiation dose is a concern in children. Objective To characterize radiation exposure during cardiac CTA, and to prospectively optimize the balance between dose and image quality in individual patients Materials and methods In this prospective study, we measured radiation exposure of children during cardiac CTA with external (thermoluminescence and MOSFET) dosimeters, and correlated these with recorded scan parameters and manufacturer-supplied CTDI and dose-length products, which were used to calculate effective doses using age-adjusted conversion factors. Recorded patient parameters included age, weight, gender and clinical indication. Data were collected on 30 cardiac CTAs, done on three different multidetector scanners using a variety of techniques tailored to patient age, weight, size and specific scan indication. Depending on indication, we used (prospective/retrospective) cardiac gating techniques or no gating. Image noise was measured as the standard deviation of attenuation values in soft tissues and enhanced vasculature. Four aspects of image quality were independently scored by two cardiac radiologists. During interval evaluations, we identified opportunities for further dose reduction while maintaining diagnostic image quality Results There was a highly significant correlation between measured skin exposure and CTDI (p<0.005), with a regression coefficient of 2. A broad range of skin exposures (highest/lowest= 85) and effective doses (46) was encountered, reflecting the heterogeneity of our patient population and, consequently, the utilized scan parameters. Exposure, effective dose and image noise varied as expected with scan parameters (mainly mA and kVp), but subjective image quality was not affected by our increasingly aggressive implementation of reduced dose techniques during the course of the study
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Conclusion Despite a wide variety of scanning techniques, CTA radiation exposure and dose can be minimized with regard to optimization of image quality, tailored to individual patient parameters and clinical indication
079 Echocardiography, cardiac catherisation and cMRI in the follow-up of fallot patients—performance evaluation E Sorantin, A Gamilllscheg, G Ehrlich, N Zuba, S Travar Department of Radiology Graz, Austria Background Right ventricular dilatation due to pulmonary insufficiency represents one of the most troublesome late complications in Fallot patients, thus making valve replacement necessary. Therefore reliable and robust monitoring examinations are mandatory. Follow-up strategies include clinical examinations, 24 h ECG as well as echocardiography and cardiac catherization (CC). Unfortunately reliable right ventricular volumetry and quantitative assessment of pulmonary insufficiency is getting nearly impossible in the adolescent and adult Fallot patient. Recently cardiac magnetic resonance imaging (cMRI) and cardiac CT was found to be the imaging modalities of choice in the follow-up of CDH patients. Objective the aim of the study was to validate the results echocardiography and CC against the results of cMRI in Fallot patients. Material and methods Fifteen Fallot patients formed the study group (mean age 24±10.16a). All patients underwent echocardiography, CC and cMRI (including ventricular volumetry and flow measurements in ascending aorta and pulmonary artery). Relevant cardiac performance markers like end diastolic right ventricular volume (normalized to body surface area—BSA) and pulmonary regurgitation fraction (PRFR) on cMRI were compared to pulmonary insufficiency degree in echocardiography and CC. Results On cMRI 11 patients showed severe right ventricular dilatation (mean 163±33.4 ml/m2 BSA) due to severe pulmonary regurgitation (PRFR 39±0.16%). On echocardiography pulmonary regurgitation was found to be grade 1 and 2, and the PFRF on cMRI found to be 18.8±21.4% for grade 1 and 28.7±18% for grade 2. On CC pulmonary regurgitation was found to be grade 2 to 3 and the corresponding cMRI PFRF 36.54±6.7% and 35.21± 12.6% respectively. Conclusion Fallot patients grading of pulmonary insufficiency by echocardiography and CC does not predict the amount of the regurgitated volume and therefore is not a relevant performance marker. For follow-ups cMRI should be used instead.
080 Pre and post-operative evaluation of aortic coarctation with magnetic resonance tomography T Yalynska, R Tammo, Y Yershova, N Rokitzkaja, O Kondrachuk Ukrainian Children Cardiac Centre, Kyiv Background Aortic coarctation accounts for 6–8% of live births with congenital heart disease and refers to an area of narrowing of
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the thoracic aorta in the region of insertion of the arterial duct with or without additional abnormalities of the aortic arch. Objective To assess the value of the MRI in the diagnosis of coarctacion of the aorta (CoA). Materials and methods In total, 66 patients (range 2 days to 17 years) were included in this study. Patients were divided in two groups. Group A patients (n=44) with suspected or proven CoA; group B patients (n=22) after surgery correction CoA. All patients underwent MRI (black-blood turbo spin-echo, velocity-encoded cine sequences and contrast-enhanced MR angiography). MRI examinations were performed on 1.5T scanner. Nine patients from group B (41%, 9/22) were underwent MRA twice-before and after operation. Results In group A MRI visualized normal aortic arch in 9% (4/ 44); CoA in 72.7% (32/44), in two cases (6.2%, 2/32) with hemodynamic interrupted aortic arch; hypoplasia aortic arch in 11.3% (5/44): two patients segment A, 1—segment B, 2— segments A, B; kinking in 6.8% (3/44). MRI detected localization and degree stenosis, MRA demonstrated of the collateral pathways. In group B postoperatively MRI depicted three recoarctation (13.6%, 3/22), narrowing segment B were detected in two cases (9%, 2/22), deformation of arch was in 13.6% (3/22). In group B MRI clearly identified preoperatively CoA in nine of nine cases confirmed by surgery. In 28.7% (19/66) CoA was associated with other cardiovascular anomalies. Conclusion MRI provided the critical anatomic information required for preoperative assessment of the CoA, including demonstration of dilated collaterals arteries. MRI is very useful for non-invasive follow-up after surgical repair. 081 Morphologic and functional evaluation of the extracardiac right ventricle to pulmonary artery conduits: MRI study Oleksandr Kondrachuk, Tetyana Yalynska, Yevgeniya Yershova, Nadija Rokitska, Illya Yemets Ukrainian Children’s Cardiac Center Background Extracardiac right ventricle to pulmonary artery (RVPA) conduits are used in the correction of congenital and acquired heart disease. Doppler echocardiography provides only semiquantitative estimation of conduit regurgitation and has limitations for morphologic evaluation because of the retrosternal location of the conduit and postoperative changes. Objective The aim of this study was to assess the value of cardiovascular magnetic resonance imaging (MRI) for morphologic and functional evaluation of the RV-PA conduits. Materials and methods Twenty-eight patients mean age 11.0± 7.3 years with RV-PA conduits were included in the study. Time from operation ranged from 7 days to 8.7 years. MRI studies were performed on 1.5 T scanner. Results MRI allowed morphologic evaluation of the RV-PA conduits in all examinations. The mean pressure gradient determined by velocity-encoded cine MRI was 16.3 ± 11.4 mmHg. Significant conduit obstruction (pressure gradient >30 mmHg) was observed in three individuals. The mean
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regurgitant fraction was 16.5±16.7%. Eight patients had conduit regurgitation >20%. Conclusion Cardiac MRI is a valuable tool for morphologic and functional evaluation of the RV-PA conduits in children and young adults. Possibility of the simultaneous estimation of the right ventricular volumes and ejection fraction makes MRI the excellent long-term follow-up method. 082 MRI assessment of branch pulmonary arteries and aortic roots following the arterial switch operation S Maroo Royal Hospital For Sick Children, Glasgow Background The arterial switch operation (ASO) which involves transection and reanastomosis of the aorta and the pulmonary trunk and relocation of the coronary arteries has become the preferred method of surgery for transposition of great vessels (TGA). The Le compte manouvre results in mild compression and stretching of the pulmonary arteries (PA) as they pass backward around the ascending aorta (AA).Complications of ASO include pulmonary stenosis and aortic incompetence. Objective To retrospectively assess branch PA and AA anatomy and flows in patients after ASO using magnetic resonance imaging (MRI). Materials and methods Eleven patients (six females, age range 3– 18 years, mean 10 years) who had undergone ASO with le compte manouvre underwent MRI to assess the branch PA and AA. Five studies were done under general anesthesia. MRI indications included poorly visualised branch PA in seven, assessment of right ventricular size in two ventricular volumes in three and right ventricular outflow tract assessment in one. Post processing was done on a workstation. Results The right PA was flattened between the aorta and superior vena cava in eight patients, normal in two patients and dilated in one. Five PA were regurgitant with the regurgitant fraction ranging from 6–43%. The left PA was diffusely hypoplastic in five, stenosed at the origin in three and normal in three patients. There was no evidence of regurgitation. Eight patients had dilated aortic roots all showing 13–37% regurgitation. Conclusion MRI is useful in assessing previously unknown abnormalities of the PA and AA following ASO. The LPA stenosis and hypoplasia could be explained by the altered anatomy following ASO and knowledge of these abnormalities is helpful in further management of these patients.
Reserve R-083 MDCT evaluation of aortic arch abnormalities in infants Oleksandr Kondrachuk, Tetyana Yalynska, Yevgeniya Yershova, Nadija Rokitska, Illya Yemets Ukrainian Children’s Cardiac Center, Kyiv
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Background Echocardiography and magnetic resonance imaging (MRI) have established roles in non-invasive evaluation of children with aortic arch abnormalities. However, echocardiography is not always sufficient for surgical planning because of suboptimal visualization of the aortic arch and the arch vessels. Disadvantages of MRI include the lower spatial resolution compared with multidetector computed tomography (MDCT) and the need for deep sedation or general anesthesia due to the long imaging times. Objective To determine utility of MDCT in the evaluation of aortic arch abnormalities in infants. Materials and methods Forty infants (patients <1 year of age) with aortic arch abnormalities were included in the study. MDCT scans were obtained with a 16-slice helical CT. Results Six categories of aortic arch abnormalities were identified: coarctation of the aorta (n=19), left aortic arch with aberrant right subclavian artery (n=9), interrupted aortic arch (n=5), right aortic arch with aberrant left subclavian artery (n=4), double aortic arch (n=2), right aortic arch with aberrant left innominate artery (n=1). Severe compression of the trachea within the vascular ring was noted in 4 subjects. In 28 (96.6%) of 29 operated patients, surgical findings were concordant with MDCT report. Discrepancy between surgical and MDCT findings in one case was related with inability of MDCT to detect atretic portions of the vessels. Conclusion MDCT is a useful diagnostic tool for evaluating aortic arch abnormalities in infants. The fast data acquisition often enables visualization of aortic arch abnormalities without the need for sedation. Assessment of aortic arch anatomy, lung parenchyma and airways can be accomplished with a single non-invasive examination.
Scientific Session 9: Miscellaneous 084 Evaluation of dynamic airway measurements on cine MRI with varying depths of dexmedetomidine anesthesia in children Mohamed Mahmoud, Rupa Radhakrishman, Lane F. Donnelly, Todd Nick, Yu Wang, Eileen Beckman, Akila Rajagopal Cincinnati Children’s Hospital Medical Center Background The effect of anesthesia on airway tone has implications for patient safety and MR acquisition. Dexmedetomidine (DEX) is thought to have less effect on airway muscular tone than other anesthetic agents. Purpose Our purpose is to prospectively determine changes in the size of the upper airway in children with high versus low dose of DEX using cine MRI. Methods Sagittal midline MR cine images were obtained at low and high DEX levels in 23 children (mean age 5.9 years). Manual measurements of the maximum and minimum AP diameter and area were evaluated at level of the posterior nasopharynx and retroglossal airway. Imaging processing software was utilized to calculate mean change in area over time at both levels. A paired t test was utilized to evaluate for change in airway size between high and low DEX (significant if p<0.05).
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Results Seven of ten measurements show significant decrease with high compared to low DEX (mean low DEX, mean high DEX, p value): nasopharynx AP maximum diameter (6.09 mm, 5.67 mm, 0.09), nasopharynx minimum AP diameter (5.34 mm, 4.47 mm, 0.002), nasopharynx maximum area (285.68 mm2, 274.27 mm2, 0.003), nasopharynx minimum area (269.71 mm2, 256.50 mm2, 0.02), retroglossal airway AP maximum diameter (10.67 mm, 9.78 mm, 0.002), retroglossal minimum AP diameter (9.51 mm, 8.54 mm, 0.002), retroglossal maximum area (272.72 mm2, 249.26 mm2, 0.02), retroglossal minimum area (226.911 mm2, 213.56 mm2, 0.11), nasopharynx mean area change (0.16 mm2, 0.22 mm2, 0.11), retroglossal mean area change (0.29 mm2, 0.36 mm2, 0.02). Conclusion Higher dose of dexmedetomidine is associated with statistically significant airway narrowing when compared to low dose DEX. DEX does have effect on airway tone at higher doses. 085 Does CT have an additional diagnostic value over us in the evaluation of acute inflammatory neck masses in children? Katya Rozovsky, Benjamin Kopelevitz, Nurith Hiller, Natalia Simanovsky Hadassah Hebrew University Medical Center Background Imaging is used widely for the evaluation of inflammatory neck masses in children. US can differentiate between suppurative and nonsuppurative processes and aid in treatment decisions. CT is able to evaluate both superficial and deep structures of the neck, but is associated with risks of radiation exposure, contrast injection and sedation. Objective The aim of our study was to determine the additional value of contrast enhanced CT versus US in the evaluation of acute cervical inflammatory masses and for the decision of therapeutic strategy. Materials and methods A search of our hospital registry identified 210 pediatric patients admitted with acute inflammatory neck mass, between January 2005 and December 2008. All patients underwent diagnostic US and Doppler of the neck. Contrast enhanced CT was performed in 25 of these patients within 2–72 h. Correlation between the clinical and radiological findings was performed and the impact of imaging on patient management was assessed. Results US provided sufficient information in 184 cases of 185 of the patients that underwent US only. US demonstrated fluid collections in 17 patients, and successful surgical abscess drainage was performed according to US findings. In two patients without sonographic evidence of collection puncture-drainage was attempted unsuccessfully. In 167 cases an inflammatory process was successfully treated conservatively. In one patient with no evidence of collection on US an abscess was drained surgically. In the 25 patients with both US and CT studies additional significant information was obtained in four cases airways compromise in two and collections in two. Conclusion US provided sufficient information about the nature and extent of the inflammation in the absolute majority of the patients and should be regarded as the main, and in most cases
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single, imaging modality. CT should be reserved for patients with aggravating clinical course and suspicion of deep neck infection or airway compromise.
086 Incidental thyroid abnormalities identified on neck ultrasound for non thyroid disorders Shivaram Avula, Alan Daneman, Oscar M Navarro, Rahim Moineddin, Stacey Urbach, Denis Daneman Hospital for Sick children, Toronto, Ontario; University of Toronto, Toronto, Ontario Background The rate and spectrum of incidental thyroid lesions found on ultrasound (US) examination in children has not been documented in the literature. Objective To determine the rate and spectrum of incidental thyroid lesions on US in children with no known thyroid abnormality. Materials and methods Retrospective analysis of clinical and ultrasound findings in all children who had a neck ultrasound for non-thyroid related indications in the 2-year period, January 2006–December 2007. Results Review of 1228 non-thyroid neck US examinations. The thyroid was depicted in 289 (age range = 1 day–17.5 years; mean—6.2 years; 1.2M:1F) and incidental thyroid abnormalities were detected in 52 (18%; age range = 1 month–17.3 years; mean—8.3 years; 1.1M:1F). In 35 there were small (<4 mm), single/multiple, well defined cysts, some of which contained a hyperechoic punctate focus. In nine there were hypoechoic, solid nodules (seven heterogeneous; two homogenous) with smooth, straighter margins with echogenicity similar to the thymus suggesting intra-thyroid ectopic thymus (ITET; mean age—2.5 years; 8M:1F). In three others there were tiny hyperechoic foci suggesting calcification without nodules. Other abnormalities included hypoechoic target like lesions (N=2), isoechoic nodule (N=1), multiple hypoechoic foci (N=1) and non-visualized thyroid lobe due to contact with an abscess (N=1). On clinical follow-up (10 months–2.8 years), none of the patients have developed thyroid dysfunction or malignancy. Conclusion There is a spectrum of abnormalities of the thyroid which are commonly seen in children having neck US examinations for non-thyroid related indications. Our data shows no significant development of thyroid dysfunction or malignancy. These US findings should be interpreted cautiously avoiding unnecessary referrals and investigations. ITET occur much more commonly in younger boys and should be considered particularly if the lesion has characteristics similar to thymus. 087 Exposure levels from paediatric multi-detector row CT: results of the 2007–2008 SFIPP survey HJ Brisse, B Aubert Institut Curie, Paris France and Medical Radiation Protection Expertise Unit, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, France
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Background Improvement in MDCT technology now allows numerous acquisitions to be easily and rapidly performed, leading to a possibly marked increase of the dose to patients. The stochastic risk related to ionizing radiation is higher in children than in adults and managing patient dose is therefore a major concern in pediatric MDCT. Objective To assess the current exposure levels in paediatric MDCT from the SFIPP (Société Francophone d’Imagerie Pédiatrique et Prénatale) corresponding hospitals and to compare to published international reference levels and recommendations. Materials and methods Tube potential and CTDIvol values from routine protocols were recorded for eight routine MDCT protocols and three age-groups (1, 5 and 10 years). Comparisons were made with UK national reference levels, German and Swiss surveys and recommendations from both the International Radiation Protection Commission and the Alliance for Radiation Safety in Pediatric Imaging. Results Protocol data from 20 of 29 centres were obtained. 97% of protocols were associated with tube potential ≤120 kVp. The 75th percentiles of CTDIvol associated with MDCT protocols for 1year, 5-year and 10-year-old children, respectively, were the followings: 31, 39.5 and 49.5 mGy for “head” protocols; 24, 22 and 24 mGy for “head and neck”; 11, 11 and 11 mGy for “sinus”; 46, 71 and 87 mGy for “petrous bone”; 3, 3.5 and 5.5 mGy for “chest”; 2, 3 and 4 mGy for “lung low-dose”; 4, 4.5 and 7 mGy for “abdomen/pelvis”; and 7, 11 and 12 mGy for “bone”. Conclusion This survey provides an accurate description of the current paediatric CT practice among SFIPP reference centres. Relatively large doses discrepancies still remain between centres as well as between comparable surveys in Europe and international recommendations.
088 Dose reduction in scoliosis follow-up using a new slot—scanner radiographical system Sylvain Deschenes, Guy Charron, Gilles Beaudoin, Marie-Claude Miron, Stefan Parent, Hubert Labelle, Josee Dubois University of Montreal Background Based on their physical properties, X-ray slotscanners show the potential to reduce scattering and produce image quality comparable to CR systems using less radiation. Objective Our work validates this assertion by comparing a new slot-scanner to a CR system through a wide-ranging evaluation of dose and image quality for scoliosis exams. Materials and methods Evaluation of spine imaging was conducted on the EOS slot-scanner, a bi-planar system that acquires simultaneously orthogonal images using fan beams coupled with linear gaseous detectors, and a standard Fuji FCR 7501S system. Fifty patients were enlisted to undergo exams on CR and EOS one after the other. Lateral and postero-anterior images were acquired consecutively with the CR and simultaneous with EOS. Exposure was set to give equivalent signal-to-noise ratios in the images. Entrance skin dose was measure with optically stimulated luminescence dosimeters placed near radiosensitive regions on the patient
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before each exam. Effective dose was then evaluated by Monte-Carlo simulation. Four experts evaluated the images in a randomized order using a questionnaire targeting anatomic landmarks. Structure visibility was rated on a 4° scale. Image quality assessment was analyzed using a Wilcoxon signed ranks tests. Results Average skin dose on the EOS was reduced from six to nine times in the thoraco-abdominal region, ranging from 0.11 to 0.30 mGy while the CR exam’s dose span from 0.73 to 2.47 mGy. Even with this dose reduction, image quality was significantly better with EOS for all structures in the frontal view (p<0.006) and lateral view (p<0.04), except for lumbar spinous processes, better seen on the CR (p<0.003). Conclusion EOS system offers overall enhanced image quality while reducing drastically the dose. 089 How much is the radiation awareness among pediatricians in Turkey ?: preliminary results of an ongoing survey Ayse Secil Eksioglu, Cigdem Uner Dr. Sami Ulus Children’s Hospital Background Rapid advances in CT technology have resulted in an exponential increase both in the number and variety of applications. Children being more sensitive to radiation than middle aged adults by a factor of 10 are the ultimate risk group. Objective As the number of publications about pediatric dose issues increased by time the level of radiation awareness among pediatric radiologists has certainly increased. But we actually do not know much about the pediatricians who are the ones requesting the CT exams. To our knowledge there is no published data from Turkey about radiation awareness of pediatrists. Materials and methods Multiple choice survey. Results Of 123 respondents only 8.8% were aware of the ALARA principle. Only 10.5% were correct in their estimate of the approximate life-time cancer risk associated with pediatric CT exams. Of all responses, 78.5% regarding the estimated radiation dose equivalents were underestimates. Ninety-six percent of the pediatricians did not receive any formal kind education on radiation issues. There was no statistically significant difference regarding the correct answer rate between the residents and the specialists. Conclusion The radiation awareness among Turkish pediatricians is generally low as their colleagues from other countries. They need more education on the subject and as radiologists this is partly our responsibility. 090 Detection of epidermal thickening in GJB2 carriers with epidermal US PP Guastalla, F Zennaro, P Gasperini IRCCS Burlo Garofolo Trieste
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Background To verify the possible presence of the phenomenon of epidermal thickening in a white population owing to GJB2 carrier status. Objective To measure epidermal thickness by using skin ultrasonography (US) in a series of healthy control subjects and obligate carriers for the worldwide most frequent form of congenital hearing loss owing to the mutated alleles of the connexin 26 gene (GJB2). Materials and methods The protocol, coupled with a new sonographic probe specifically designed to analyze epidermal thickness and a dedicated algorithm to classify individuals in groups, has been patented. Institutional ethics committee approval and patient consent were obtained. After a preliminary study in 20 subjects aimed at defining the best body site and instrument and protocol for US, a total of 303 individuals (237 healthy subjects, 51 carriers, and 15 homozygotes) were tested at midline forehead by using a linear large band probe with a frequency ranging from 6 to 15 MHz to determine epidermal thickness. Variance and linear regression analyses were performed. Regression coefficients were then used to obtain measurements of thickness corrected for age and sex. Results GJB2 obligate carriers had a significant increase in epidermal thickness compared with control subjects. GJB2 status explains about 50% of this variability, whereas an additional 26% is explained by sex and age. Results led to the development of a possible screening protocol with a 98% sensitivity and 93% specificity in subjects aged 20 to 80 years, with a likelihood ratio of a positive test of 14:1. Even better results (100% sensitivity and 98.3% specificity) were obtained in an analysis of people of reproductive age only. Conclusion Epidermal thickening in the white population owing to GJB2 carrier status can be detected by using US. This measurement could provide a simple, noninvasive, rapid and sensitive test for carrier screening. 091 Non-contrast enhanced MRI of abdominal vessels before renal transplant Kate Park, Oystein E Olsen, Stephen Marks, Kirsteen MCDonald Great Ormond Street Hospital Background Prior to renal transplant surgery patients benefit from imaging of the abdominal and pelvis vessels. MRI is often used due to the shortcomings of US in this cohort, which has a high incidence of vascular abnormality. Use of gadolinium is now a contraindication due to the risk of nephrogenic systemic fibrosis. Objective To evaluate non-enhanced MRI for visualisation of vascular anatomy pre renal transplant. Materials and methods A prospective study of 11 children (2– 15 years) pre transplant MRI. SSFP sequences or time-of-flight (TOF) angiography were used. US was performed, blinded to MRI findings, within 48 hours of the MRI, in eight children. A visual analogue score was given by the operator to reflect the quality of the images obtained and confidence in their findings.
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Results Five US scans (63%) were completed with all vessels adequately visualised. Of these, three (60%) correlated with MRI findings. Mean visual analogue score for the clarity of the US views was 5.3 out of 10. Of the MRI scans, the vessels were adequately visualised in 10 (91%), arterial images were not obtained in one. There was agreement between the MRI and US in four and disagreement in four cases, three in which an occluded vessel on MRI was reported as patent on US, and one in which a vessel was reported as patent on MRI and occluded on US. Conclusion The abdominal vasculature can be adequately imaged using unenhanced SSFP and TOF sequences. 092 Evaluation of interoperator variability of TSE-STIR whole body MRI (WB-STIR) in Pediatrics Maria Beatrice Damasio1, Alessia Maccagnano1, Claudio Granata1, Maria Chiara D’Auria1, Angela Pistorio2, Paolo Tomà1 G Gaslini Children’s Hospital, Genova Background WB-STIR is an emergent tool in pediatrics. It is a sensitive, radiation-free MRI technique for a whole-body screening in a single examination. Lesion detection is based on the contrast between the signal intensities of pathologic and normal tissues. Because of the simultaneous evaluation of the entire body, some lesions (small, at the periphery of the FOV) may be missed by the reader without a systematic reading approach. Objective To evaluate reproducibility and concordance of WBMRI, between independent readers, in terms of lesion detection and characterization. Materials and methods We considered 53 consecutive WB-MRI (Body coil, TSE-STIR sequence: TR2500, TE60, TI150, slice thickness 5 mm, gap1, acquired in coronal and sagittal planes) performed in 39 patients (22M,17F; median age 10 years, range 1–20 years) from July 2007 to July 2008. MRI studies were reviewed by two independent radiologists according to a standardized reading protocol, looking for any abnormal hyperintensity (AH) considering analytically bones, parenchymas, lymphonodes and soft tissues. Each AH was also classified according to signal intensity (moderate/strong) and size (focal/ diffuse). Results were analyzed for concordance with Cohen’s coefficient of agreement. Results Concordance on presence/absence of AH was almost perfect (>0.8–1) in the bones and soft tissues of arms, forearms, pelvis, thighs, legs, dorsal and lumbar spine, and parenchymas (lungs, liver, spleen and kidneys); substantial (>0.6–0.8) in skull, clavicles, sternum, ribs and scapulas; sufficient (>0.21–0.4) in cervical spine; poor (0.01–0.2) in nodes. Concordance on AH classification resulted substantial (>0.6–0.8) for both signal intensity and size. Conclusion Evaluation of WB-MRI with STIR sequence, with a systematic approach, shows high reproducibility and concordance of the results, between independent operators, in terms of lesion detection and characterization.
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093 Pharmacokinetics and safety of 1.0 m macrocyclic gadobutrol in MRI in 138 paediatric patients—a multinational multicenter trial W Hirsch1, Z Jirakova-Trnkova2, M Schultze-Mosgau2, G Hahn3 University of Leipzig, Leipzig, Germany1, Bayer Schering Pharma, Berlin, Germany2, Carl Gustav Carus Dresden University of Technology, Dresden, Germany3 Objective To investigate pharmacokinetics and safety of gadobutrol in paediatric patients (2–17 years). Materials and methods One hundred thirty-eight paediatric patients scheduled for CE-MRI of brain, spine, liver, kidney, or MRA received a single intravenous injection of gadobutrol (0.1 mmol/kg body weight). Patients were stratified by age. Blood and urine samples were analyzed for gadolinium concentrations. Plasma data from 130 patients were evaluated using a non-linear mixed effects model. Results Median estimates of total body clearance [L/h] per age group were 3.24 [1.53, 6.62] (all ages), 2.07 [1.45, 3.83] (2– 6 years), 3.28 [1.81, 5.93] (7–11 years), 4.90 [2.52, 7.37] (12– 17 years) and body weight normalized median values [L h−1 kg−1] 0.10; 0.13, 0.10, and 0.9 respectively. Median estimates of total volume of distribution [L] were 5.96 [3.27, 13.2], 3.83 [3.24, 6.33], 5.98 [4.06, 11.69], 10.02 [5.16, 14.12] and body weight normalized median values [L/kg] 0.20, 0.24, 0.19, and 0.18 respectively. Median gadolinium concentrations at 20 min p.i. were simulated using a population pharmacokinetic model and ranged from 414 μmol/L (13 kg subject) to 518 μmol/L (65 kg subject). On average, 77% of administered dose was eliminated via kidney after 6 h p.i., indicating that, same as in adults, gadobutrol is renally excreted. Incidence and profile of adverse drug reactions was similar to adults. Conclusion Differences in pharmacokinetics were attributed to body weight. As no additional independent effect of age was found, no dose adjustment from the standard dose of 0.1 mmol/kg BW gadobutrol is necessary in paediatric patients aged 2–17 years. Safety and tolerability of gadobutrol was confirmed in this paediatric population. 094 Safety and image quality achieved with gadobenate dimeglumine in pediatric subjects referred for routine contrast-enhanced MR imaging Guenther Schneider, Hellmut Schuerholz, Peter Fries, Miles Andrew Kirchin, Marcus Katoh, Arno Buecker Saarland University Hospital, Homburg, Saar Germany Background Gadobenate dimeglumine is a higher relaxivity gadolinium contrast agent with partial hepatobiliary excretion that may be useful for MR imaging in children. Objective To retrospectively determine the safety and image quality achieved with gadobenate dimeglumine in pediatric subjects referred for diagnostic or follow-up MR imaging.
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Materials and methods Two hundred one pediatric subjects (age range, 0–15 years) referred for enhanced MRI received gadobenate dimeglumine at either 0.05 (liver, abdominal, musculoskeletal, brain, other rare indications) or 0.1 (cardiovascular, MRurography) mmol/kg. Very young patients underwent MRI either in sedation or general anesthesia while patients below 8 years with congenital heart disease (CHD) underwent MRA under intubation with controlled ventilation. Monitoring for adverse events was performed for at least 24 h after injection. Depending on clinical necessity, laboratory measurements as well as vital sign and ECG determinations were made before and after the examination. Safety determinations were made by age-group, clinical indication and dose administered. Results No adverse events were noted. No relevant changes of creatinine or bilirubin levels were noted although ongoing chemotherapy in some patients resulted in non-CM related changes in some laboratory values (e.g. thrombocytes, liver enzymes, lactate dehydrogenase). A total of 48 subjects underwent two or more contrast-enhanced examinations while 15 underwent three or more, and one subject ten examinations (316 exams overall). No detrimental effects of gadobenate dimeglumine on renal function were noted and no patients exhibited symptoms of NSF. Image quality was excellent and particularly beneficial in patients undergoing CE-MRA for CHD. The hepatobiliary imaging properties of gadobenate dimeglumine were valuable for accurate differentiation of metastases and from frequently observed regenerative lesions in patients with malignant tumors. Conclusion Gadobenate dimeglumine is safe and effective for imaging pediatric patients and can be used effectively at a lower dose for most abdominal and vascular applications. 095 Thoraco-abdominal pediatric CT—single acquisition with biphasic intravascular injection of iodinated contrast Tristan Zand, Luca Spadola, Mehrak Anooshiravani, Laura Merlini, Solène Ferey, Sylviane Hanquinet Geneva Children Hospital Background Minimizing irradiation in children is essential but should not decrease diagnostic quality. Intravascular contrast injection protocols play an important role in this process towards better diagnostic potential of CT. Objective Definition of an injection protocol for simultaneous arterial and venous enhancements of anatomical structures in a single thoraco-abdominal acquisition. Materials and methods From October 2006 to December 2008, 249 thoraco-abdominal CTs where included (age range 1 month– 21 years), using a Siemens Somatom 64 CT and Acupaq 300 i.v. contrast in a Medrad dual-head injector. Exposition using automatic variation was progressively diminished within the limits defined by the literature. Based on intravascular injection chronology, biphasic injection was programmed in order to optimize anatomical differentiation of both arterial and venous nature in a single acquisition. Biphasic intravascular injection included a venous (80%) and arterial bolus (20%), and total contrast volume was limited to 1.5 cc/kg. Reconstructions
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included medium and fine-width axial and coronal slices, using soft and hard filters. Diagnostic value was the only criteria for image quality. Signal-to-noise ratio was not a criteria as it does not directly relate to diagnostic value. Results A CT scan was deemed successful when correct definition of anatomical structures was obtained in a single acquisition, and when the clinical differential-diagnosis could be included or excluded. Enhancement of both arterial and venous nature following our protocol offered greater contrast and comfort for interpretation compared to traditional monophasic injection. In these examinations CTDIvol ranged from 1.42 to 4.45 mGy. None showed insufficient diagnostic quality. Conclusion Biphasic injection enhanced differentiation of anatomical structures and enabled us to optimize irradiation without diagnostic information loss in a single CT acquisition. Moreover, it induced greater homogeneity and clarity in our CT scan workflow. 096 The incremental diagnostic yield of low-dose CT angiography for the evaluation of early vascular complications after liver transplantation in children Els L F Nijs, Jeffrey Hellinger, Kassa Darge, Elizabeth Rand, Monica Epelman Children’s Hospital of Philadelphia Background Hepatic artery thrombosis is a devastating, life threatening complication that may result in allograft loss. The diagnosis of this entity is usually made by color Doppler sonography (CD US), however, this technique requires a high degree of expertise and patient cooperation. Objective Report the findings of biphasic low-dose CT angiography (CTA) in six children with suspected vascular complications after recent liver transplantation. Materials and methods Between January 2006 and December 2008 a total of six children (three females, three males), age range 0.9–15.7 years (mean 5.7 years) underwent low-dose CT angiography. Patients medical records and imaging studies (including color Doppler ultrasound, low-dose abdominal CT angiography and hepatic angiogram) were reviewed independently by two experienced radiologists. Three patients had a split liver allograft (left lateral lobe) and three patients received a whole liver. The study was done retrospectively with IRB approval. Results A total of six CTAs were performed in the immediate postoperative period (up to 14 days after surgery). In four of six a hepatic artery stenosis was diagnosed by CD US but in one of six a patent hepatic artery was found with biliary duct dilatation filled with sludge, in one of six only a size discrepancy was found, in one of six a complex anatomy was revealed with a ligated hepatic artery but preserved left gastric artery and in one of six hepatic artery stenosis was confirmed by CTA and hepatic angiogram. In one of six CD US could not demonstrate the hepatic artery in the hilum and was normal on CTA. In one of six CD US demonstrated a portal vein stenosis while CTA demonstrated a size discrepancy between donor and recipient.
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Conclusion In five of six patients a significant change was made in patient management in the early postoperative period of their liver transplant based on the results of a low-dose CT angiography. 097 Comparison of paper print and soft copy reading in plain paediatric radiographs AT Maydell 1, S Andronikou2, C Ackermann1, AF Bezuidenhout1 1. University of Stellenbosch and Tygerberg Hospital, Cape Town, South Africa 2. University of Cape Town, South Africa Background With the introduction of a Picture Archiving and Communication System, Computed and Digital Radiography, reading digital images takes place from a computer screen. Laser paper print rather than laser film would be a significantly cheaper option for hard copy production, but would need to demonstrate acceptable diagnostic quality compared to the reference standard of screen reading. Objective To compare paper printout reading with soft copy reading of paediatric CR studies from a paediatric hospital X-ray department in order determine the diagnostic quality of the paper print hard copy format versus the reference: screen reading. Materials and methods A comparative study of 51 digital paediatric CR radiographs presented in laser paper print and soft copy format to determine the diagnostic value of the paper print when compared to the reference standard of screen reading. Results Chest radiography had a poor sensitivity of 66.1% while musculoskeletal and abdominal radiography acceptable sensitivities of 90% and 99% respectively. Specificity was excellent for the different regions (98.6–99.5%). Conclusion The paper print format should not be used for diagnostic purposes in chest radiography, but may still be used for demonstration when accompanied by the radiology rapport obtained from soft copy reading. Favourable results in abdominal and musculoskeletal radiography suggest a potential diagnostic use for paper prints, although further studies would be needed to confirm this assumption owing to the low number of abdominal radiographs and lack of musculoskeletal case variety in our study.
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R-098 Imaging findings in paediatric television topple injuries Shivaram Avula, Paul S Babyn, Blake Papsin, William J Mounstephen, Ted Gerstle, Susan Blaser Hospital for Sick children, Toronto, Ontario Background Paediatric injuries sustained from falling television sets are not uncommon. There has been an increase in the number of injuries in the past two decades. These television topple (tipover) injuries (TTI) vary in severity and distribution ranging from significant head injuries to minor extremity trauma. There is limited published literature on the imaging findings in these injuries.
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Objective To illustrate the pattern and distribution of radiological findings in children with TTI, who presented to a single tertiary paediatric centre. Materials and methods Retrospective analysis of the imaging and clinical findings in children with a history of TTI during a 12 year period (1st May 1996 to 30th August 2008). Results A total of 85 patients with a history of TTI presented to our institution over a 12 year period. Plain radiographs and/or CT were used at presentation. Fifty-five patients (age—9 months to 15.9 years; 66% male: 34% female) had abnormal radiological findings. These included 29 patients with head injuries. Nineteen children sustained head injuries with skull fractures involving calvarium (N=13); skull base (N=12); and/or facial bones (N=2). Three of the 10 children with petrous temporal bone fractures sustained; petrous crush fractures; typical of bitemporal compression. Complications from head injuries included conductive deafness in four children, facial nerve weakness in four and sixth nerve weakness in three. Twenty-eight patients sustained injuries to the torso and extremities, including three patients with significant visceral injuries (lung, liver and pancreatic injuries). Twelve children with extremity injury sustained 17 individual fractures, predominantly involving the lower limbs. There was one mortality involving a 27 month old child. Conclusion Accurate identification of the various lesions in children with TTI can play a vital role in the care of these patients. R-099 Nasal gliomas and other congenital midline nasal masses: MRI and CT findings Cinzia Orazi, Paolo M.S. Schingo, Emanuela Sitzia, Giovanni Carlo De Vincentiis, Rita Devito, Sergio Bottero Bambino Gesù Children’s Hospital Rome, Italy Background Congenital midline nasal masses are rare anomalies, usually detected at birth, which include dermal sinus cysts, encephaloceles and gliomas. The term glioma is a misnomer because they are not true neoplasms, but they can be considered as sequestered brain tissue, displaced by closure of the anterior neuropore during embryonic development. These developmental nasal masses share similar embryogenetic origins, resulting from faulty separation of neuroectodermal from ectodermal tissue during the development of the nose and frontobasis, and must be considered as potentially having intracranial extension, this being the rule in encephalocele. Nasal gliomas can be extra-nasal, lying external to the nasal bones, (60% of cases), intranasal (30%) or more rarely can present as mixed lesions. Objective To assess the role of imaging in the differential diagnosis of congenital nasal masses in newborns and infants. Materials and methods We describe MRI and CT findings in five cases of nasal gliomas, and in one dermoid, one encephalocele, and two angiomas affecting the anterior region of the nose. Results Both techniques allowed definition of the extent of intraand extra-nasal component of these congenital masses, also involving the parapharyngeal and pterygopalatine space. Anyway,
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MRI better defined the extension and the relationship with the subaracnoid space. Bony defects were better shown by CT, but the evaluation was hindered by the physiologically incomplete ossification of the ethmoid. Conclusion It is useful to assess preoperatively the intra-ed extracranial extension of masses involving the anterior region of the nose. CT can provide useful information on bony defect, while MRI utilizing multiplanar imaging, allows a better definition of structural components and intracranial extension. Definitive diagnosis, anyway, can only be obtained by means of histological examination. R-0100 Pilot project on teleradiology from home: our experience at IRCCS Burlo Garofolo F Zennaro, M Bava, P P Guastalla IRCCS Burlo Garofolo Trieste Background The Burlo Garofolo children hospital in Trieste, Italy, is a highly specialized hospital where 24/7 availability is not guaranteed nor necessary. Subspecialists such as Pediatric radiologists are generally very rare. Teleradiology allows for trained specialists to be available 24/7. Objective The project’ objective is to use teleradiology to provide a report from home without the use of external experts, not specialized in pediatric radiology. The system can also be used to assist newly appointed radiologists. Materials and methods Two senior radiologists use the system installed in their homes. They have a laptop with a special external monitor, where they can provide a report as if they were in the hospital. Connection to the hospital’s PACS is guaranteed by a highspeed network connection and security is guaranteed by a tunnel. The document is signed digitally and can be remotely printed so that the technical staff can give it to the patient in its final form. Two senior members out of a staff of six use the system. Results Between June 2007 and December 2008, 1,320 exams were executed. Of these, 612 were reported remotely. Some of the exams reported by young doctors were also checked remotely. Conclusion Teleradiology helps radiologists to ensure a 24/7 service without the need of being physically in hospital. The service offered is better for patients too. Young doctors are helped during their first months of service.
Scientific Session 10: Interventional
0101 Drainage of deep pelvic abscesses in children using transrectal ultrasonography and fluoroscopy guidance Korgun Koral, Betul Derinkuyu, Elizabeth Lagomarsino, Joseph Murphy University of Texas Southwestern Medical Center Background Imaging guided drainage of deep pelvic abscesses in children is discussed.
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Objective To describe our experience of transrectal drainage (TRD) of deep pelvic abscesses in children using transrectal ultrasound (TRU) and fluoroscopy guidance. Materials and methods Retrospective review of interventional radiology records from January 2005 through November 2008 yielded 29 TRDs performed using TRU and fluoroscopy guidance. There were 17 boys and 12 girls. The mean age was 10.8 years (3.8–15.9 years). Fifteen patients had perforated appendicitis as the cause of deep pelvic abscesses. Eleven patients underwent drainage/aspiration following laparoscopic (n=9) and open (n=2) appendectomy. The remaining three patients had pelvic abscesses/collections secondary to Crohn disease, gunshot wound and laparotomy performed for release of adhesions. Eight patients underwent percutaneous drainage of synchronous abscesses elsewhere in the abdomen. Peripherally inserted central catheter (PICC) lines were placed in 24 patients prior to drainage because of expected intravenous antibiotic therapy. In six patients the abscess/collection were multiseptated, therefore only aspiration was performed. Abscess volumes were calculated in 25 patients who had CT scans. The mean abscess volume was 69.5 ml (18– 341 ml). Of the 22 transrectal catheters that were placed four were 8.5 French, 16 were 10 French, one was 10.2 French and one was 12 French. Results Of the 29 attempted transrectal drainage/aspiration, 27 were successful (93.1%). There were no complications. No additional drainage was necessary in any of the patients. The average catheter dwell time was 4.1 days (1–7 days). All catheters were tolerated well. The 15 patients with perforated appendicitis subsequently had scheduled appendectomies 4–6 weeks after drainage. Conclusion TRD of deep pelvic abscesses with TRU and fluoroscopy guidance in children is a safe, fast and reliable procedure. 0102 Aspiration and drainage of abdominal fluid collections in children N Tahir, A Barnacle, D Roebuck Great Ormond Street Hospital Background Various types of abdominal fluid collections may be aspirated using image-guided techniques, with or without the insertion of one or more drains. Objective To review our experience of the aspiration and drainage of abdominal collections in children. Materials and methods This is a retrospective review of the experience at one children’s hospital. Patients were identified and all technical details extracted from a prospectively-maintained interventional radiology database. Additional data was obtained from review of medical notes and radiology and microbiology records. Results Two hundred twenty procedures were performed in 168 patients between July 1999 and November 2008. There were 88 males and 80 females, aged from 1 day to 18 years (median 6.9 years). The success rate was 99.5%. The nature of the collections were abscess (75), ascites (61), bile (eight), CSF (five),
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lymphocele (nine), urinoma (18), gynaecological related (11) and other (33). The most commonly isolated organisms were E. coli (14) followed by other coliforms (11), Staphylococcus aureus (ten) and C. albicans (ten). Locations of the collections were upper abdominal (41), lower abdominal (69), pelvic (32), perinephric (14), other retroperitoneal (17) and generalised (46). Needle size used ranged from 23 to 14 G with the commonest sizes being 18 G (122) and 20 G (58). Drains were inserted in 59% of procedures. The commonest drain sizes used were 8.5 Fr (73) and 6 Fr (27). Complications were reported in six procedures, the most serious of which was a haemothorax which required transfusion and a delayed mini-thoracotomy. Conclusion Image-guided aspiration and drainage of various types of abdominal fluid collection are feasible and acceptably safe in children. 0103 CT image guided percutaneous drainage of abdominal abscesses in children Botsa Evanthia1, Koutsogiannis Ioannis2, Sotiropoulou Evaggelia3, Stathopoulos Konstantinos3, Thanos Loukas3 Agia Sofia Children’s Hospital Athens Objective To detect the effectiveness and safety of the CT image guided percutaneous drainage of abdominal abscesses in children. Materials and methods In our retrospective study were included 31 patients. Their age ranged from 3–14 years with a mean age of 7 years. Five of our patients had pancreatic abscesses, six pelvic, eight liver, four renal and perirenal, four splenic and five had psoas abscesses. All our patients underwent the procedure under sedation. For the procedure we used drainage catheters trocar, pigtail 7F. Results Successful and complete drainage was obtained in 27 out of 31 patients we examined (87%). The mean time we kept the catheter inside the collection was 4–15 days. The extraction of the catheter was made after the stoppage or elimination of the drainage in less than 10 cc per day or even after the improvement of the physical situation of the patient. According to the results of cytologic evaluation and fluid culture most of the abscesses were caused due to staphylococcal infection. Only one of them referred to a tbc abscess of the psoas and another one to a mycosis abscess of the pelvis. None complication was obtained in our patients. Conclusion Percutaneous drainage provides an effective and safe alternative to more invasive surgical drainage in most patients. It is a minimal invasive method with no major complications. Moreover the evaluation of the catheter’s right function is quite easy for pediatricians and does not require any special knowledge.
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Background Drainages of fluid collections in children can be challenging due to the small size of the patient associated with diverse and unusual locations of the collections. The need of drainage is essential for diagnosis and treatment Objective To illustrate a group of untraditional approaches for fluid and pus drainage in children that ass the breadth of current interventional procedures Materials and methods Retrospective review of the fluid and abscess drainages in the interventional radiology database over the past 2 years was performed searching for routes that are not traditionally describe or used for image guided interventions. Cases were examined for age, anatomy, efficacy of treatment, safety, modality of guidance and post procedural complications. Results Ten procedures were performed that were readily organized in three major categories. Four of the procedures were transhepatic drainages. Two drained pus and two addressed pancreatic fluid leaks. Four procedures were right trasiliopsoas approaches posterior to the external iliac vessels and anterior to the internal iliac vessels for a drainage of pot appendicitis abscesses located in the false pelvis that were not approachable by other interventional routes. Two infants with sepsis and airway obstruction had infected deep right neck lymphatic malformations that were approached from posteriorly via the right paraspinal muscles into the parapharyngeal neck spaces, avoiding potential injury to salivary glands ducts and the facial nerve. All ten procedures were US guided with fluoroscopic support. All procedures resulted in effective drainage and control of the fluid spaces. No major complications occurred. The transiliopsoas approach elicited greater than average pain during catheter placement as well as post procedural complains of pain with walking during recovery until the catheter was removed. Conclusion Creative in the care of children with fluid collection can be considered when based upon sound anatomic and interventional principles. We had no significant complications in our small. The transiliopsoas required more analgesia than the typical during the placement and recovery phases and we now inform families accordingly. 0105 Prognostic value of length of an asymptomatic period after first balloon dilation of esophageal stricture in children for outcome of procedure Jiří Lisý 1, Michal Rygl2, Martin Vyhnánek2, Marie Hladíková3, Jiří Šnajdauf2, Miloslav Roček1 1. Department of Imaging Methods 2. Department of Children Surgery 3. Dept. Of Informatics, University Hospital Motol, Prague 5, 150 16 V úvalu 84
0104 Untraditional routes of imaging guided fluid drainage in children Lucia Fontalvo, Paula Hernandez, Els Nijs, Ganesh Krishnamurthy, jAbhany Srinivsan, Anne Marie Cahill, Marc Keller Childen’s Hospital of Philadelphia
Background Outcome of balloon dilation of esophageal stricture is difficult to predict. Different factors play role in evaluation of prognosis of balloon dilation. Objective Authors tried to find out if length of an asymptotic period after first balloon dilation has a prognostic value for evaluation of outcome of this procedure.
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Materials and methods Length of an asymptomatic period after first dilation was prospectively observed in group of 65 children who underwent balloon dilation for esophageal stricture. Most distinct boundary of length of an asymptomatic period between successfully dilatated patients and patients who had to undergo surgery was found using ROC curve (receiver operating characteristic curve). Fisher’s exact test was used to determine statistical significance of divergence between successfully dilated and operated patients dependent on length of asymptomatic period after first dilation. Results Most distinct boundary of length of an asymptomatic period between successfully dilatated patients and operated patients was 36 days after first dilation. Shorter asymptotic interval had nine surgically treated patients and 25 successfully treated patients. Longer asymptotic interval had 31 successfully treated patients. Fisher’s exact test proved high statistical significance of difference in ratio of successfully and surgically treated patients. Exact significance two-sided (p) was 0.0023 (p<0.01). Conclusion Length of an asymptomatic period after first balloon dilation of esophageal stricture in children is statistically significant in prognosis of outcome of this procedure. 0106 Radiologic percutaneous gastrostomy and gastrojejunostomy in children T Ciftci, D Kaya, D Akinci, MN Ozmen, O Akhan Hacettepe University Faculty of Medicine Background Providing enteral nutrition in patients who can not take nutrients orally for any reason, but who have an functioning gut, is the most common indication to perform gastrostomy. At the present time three methods of placing of gastrostomies are practised. Open surgical, percutaneous endoscopic and percutan radiologic. Percutan radiologic placement of gastrostomy and gastrojejunostomy tubes has become widely used and accepted in the adult population. But placement of these tubes in children is less extensively documented. Objective To evaluate the safety and efficacy of radiologic percutaneous gastrostomy and gastrojejunostomy in children. Materials and methods From January 2000 through January 2009, a total number of 82 percutaneous catheters were placed (67 gastrostomies and 14 gastrojejunostomies) in 81 pediatric patients (53 boys and 28 girls). Patients’ ages ranged from 4 months to 16.5 years. Results Technical success rate was 100%. No procedure related mortality or morbidity was observed. Major and minor complication rates were 3.7% and 18.5% respectively. Total 25 tube maintenance problems (TMPs) were detected in 14 patients. There were three major complications (two aspiration pneumonia, one catheter site infection which require hospitalization and iv antibiotic administration). Minor complications occurred in 15 patients (nine localized site infections, two gastroesophageal reflux and four TMPs requiring secondary intervention). TMPs were as follows; accidental dislodgement (n=12), leakage from the insertion site (n=6), tube obstruction (n=2), migration (n=2), breakage (n=2) and kink (n=1).
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Conclusion In children radiologic percutaneous gastrostomy and gastrojejunostomy are safe and effective methods for long-term nutritional support. 0107 Trans-hepatic central venous access in children: review of 10 cases Lucia Fontalvo, Paula Hernandez, Marc Keller, Ganesh Krishnamurthy, Els Nijs, Anne Marie Cahill Childrens Hospital of Philadelphia Background Vascular access in pediatric patients is frequently lost because of thrombosis, infection or displacement. Children with cardiac anomalies have an additional challenge. The transhepatic central venous access is an alternative to traditional venous access Objective The objective of the study is to review a single institutional 7 year experience with percutaneous trans-hepatic central venous access in children Materials and methods A retrospective review was performed of all children in whom trans-hepatic central venous access was obtained between 2000 and 2007. Ten procedures were performed in nine patients (four males, five females) age range 0.5–19 years, mean 7.1 years. The clinical indications included: complex congenital cardiac disease in eight children, short gut syndrome in one child, and chronic renal failure in one child. In each case, the pattern of venous thrombosis precluded conventional central venous access. The technique used, types of venous occlusion, and outcomes were reviewed. Results All ten procedures were technically successful. A total of ten tunneled central venous lines were placed. Eight central lines ranged in size from 5.5–7 Fr and two lines were 10 Fr for dialysis purposes. Seven of ten tunneled central lines were double lumen and one of ten was single lumen. All procedures were performed with general anesthesia. Conclusion Trans-hepatic central venous access is a challenging but effective alternative access route. It should be considered in children with limited venous access and in particular those with complex congenital cardiac disease, in which preservation of central veins is essential for future cardiac intervention. 0108 Comparison of results of surgical and balloon-burst pyeloplasty in children B Adikibi, GAM Mackinlay, WG Manson (deceased), AG Wilkinson Royal Hospital for Sick Children, Edinburgh, UK Background Balloon-burst pyeloplasty is a minimally invasive alternative to surgery for pelviureteric junction obstruction, with major advantages in patient morbidity and duration of hospital stay. Its effectiveness in comparison to surgery in children is unreported. Objective To compare the outcome of balloon-burst and surgical pyeloplasty.
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Materials and methods A 13-year retrospective analysis of the preand post operative ultrasound and MAG3 renogram parameters and any further procedures for all patients undergoing balloonburst or surgical pyeloplasty in our institution. Balloon-burst pyeloplasty was performed by retrograde or antegrade approach with post procedural stenting for 6 weeks in all cases. A-P renal pelvis diameter (RPD) measured on US was categorised in 10 mm ranges from 1 (<10 mm) to 8 (>70 mm) and MAG3 drainage categorised from 1 (T1/2 <15 min) to 5 (Tmax >55 min). Further procedures included reinsertion of ureteric stents, balloon dilatation, surgical pyeloplasty or nephrectomy. Analysis of further procedures by chi squared test. Results Primary balloon-burst pyeloplasty (29 cases): there was a reduction in RPD and MAG3 score but further procedures were required in six (20%) cases. Secondary balloon-burst pyeloplasty, (following previous balloon-burst or surgical procedure; 21 cases): there was a reduction in RPD and MAG3 score but further procedures were required in 12 (57%) cases. Primary surgical pyeloplasty (109 cases): there was a reduction in RPD and MAG3 score and further procedures were required in 13 (12.5%) cases. There is no significant difference in the number of further procedures for primary balloon-burst pyeloplasty and primary surgical pyeloplasty. Two cases of failed primary balloon burst pyeloplasty were subsequently found to have crossing vessels. Conclusion This is the largest reported series of balloon-burst pyeloplasty in children. There is no significant difference in outcome of balloon-burst and surgical pyeloplasty (p>0.05).
0109 Cutting balloon dilatation of congenital ureteric strictures B Narayanaswamy, WG Manson (deceased), AG Wilkinson Royal Hopsital for Sick Children, Edinburgh, UK Background Congenital ureteric strictures are rare intrinsic anomalies of the ureter inferior to the pelviureteric junction, conventionally treated surgically. Objective To describe a new minimally invasive treatment with major advantages in terms of patient morbidity and hospital stay. Materials and methods Case 1: male aged 18 months with antenatal diagnosis of left hydronephrosis proven at retrograde ureterogram to be due to intrinsic ureteric stricture. Case 2: male aged 10 years presenting with loin pain proven by MRU to have a left ureteric stricture with hydronephrosis. Both had ipsilateral decrease in function. Attempted retrograde conventional balloon dilatation failed in both cases due to extreme rigidity of a tight short stricture. A 4 mm cutting balloon (Boston Scientific) was necessary in both cases to commence the dilatation process which was then completed using 8 mm conventional balloons. Indwelling ureteric stents were placed for 6 weeks following the procedures. Results The ultrasound and MAG3 parameters returned towards normal and the differential function on DMSA scan normalized in both cases. Symptoms in case 2 resolved.
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Conclusion Cutting balloon dilatation of congenital ureteric strictures resistant to conventional balloons has not previously been described, but proved an effective minimally invasive treatment in these cases. 0110 Acute limb ischaemia (ALI) from veno-arterial reflux (VAR) during sclerotherapy of soft tissue venous malformations (VMS) in children Philip John, Joao Amaral, Amin Alzahrani The Hospital for Sick Children, Toronto Background Direct puncture procedures using sclerosants are commonly used to treat symptomatic limb VMs. During direct puncture sclerotherapy, venous channel occlusion results from thrombosis and endothelial injury. Inadvertent spillage of sclerosant into arterial channels can result in acute arterial occlusions with sudden decrease in limb blood flow. Objective To report (1) the occurrence of VAR during direct puncture procedures on soft tissue limb VMs and (2) that sclerotherapy of VMs showing VAR during direct puncture can lead to acute limb ischaemia with limb threatening. Materials and methods Retrospective review on three pts showing VAR during direct puncture venography of limb VMs (located in the hand in two pts and the foot in one pt). Two of three pts underwent sclerosant injection and both developed ALI. ALI was incomplete in one pt and irreversible in one pt. Results VM associated VAR is seen from variable locations within a VM, occurs with and without tourniquet usage and is unrelated to the number of access needles placed into the VM. Variable VAR can be seen by altering tourniquet pressure. ALI only occurred when sclerosant was injected into a VM showing VAR. ALI can occur with sclerosant injected into VM locations other than those locations showing VAR. ALI occurred with liquid and foam sclerosants. In the two pts with ALI, successful revascularisation by catheter directed treatment was undertaken in one pt and partial amputation was required in one pt as partial non-viability of the limb developed. Conclusion ALI of variable severity can be seen following sclerotherapy in children with soft tissue VMs showing VAR on direct puncture venography. Meticulous direct puncture venograms may identify VAR. The avoidance of sclerosant injection in such lesions can reduce the associated morbidity from ALI.
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R-0111 Clinical validation a semi-automated software for volumetric and perfusion analysis of soft tissue venous malformation on MRI examination Veronique Caty, Gilles Soulez, Claude Kauffmann, Marie-France Giroux, Vincent Oliva, Josee Dubois University of Montreal
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Background Venous malformations (VM) are well seen on T2 weighted MRI sequences, but 2D measurements could be less reproducible because of VM irregular shapes. Also, perfusion analysis is subjective. Objective We hypothesize that software allowing 3D volumetric evaluation and perfusion analysis would be more accurate to evaluate VM response to sclerotherapy. Materials and methods Out of 44 patients who underwent baseline MRI, 19 were treated and had MRI follow-up. All patients had two 2D orthogonal STIR acquisitions followed by a perfusion study (T1) 1, 2, 5 and 10 min post contrast injection using 3D VIBE acquisitions. Blinded manual measurements of VM maximal diameter were undertaken by two investigators in three perpendicular axis on STIR acquisitions and the mean diameter was calculated. With a dedicated software (Object Research System), the same investigators performed a 3D volumetric reconstruction of VM using orthogonal STIR acquisitions. This model was fused with VIBE perfusion sequences and percentage of perfusion was analysed. Inter-observers reproduc-
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ibility was analyzed with intraclass correlation coefficient. Perfusion percentage at baseline was compared using Student’s t test between VM with a volume diminution of at least 50% and those without a significant reduction. Finally, VM variation after sclerotherapy was evaluated with manual and volumetric measurements. Results For baseline MRI, inter-observer correlations were estimated at 0.99 for volumetric measurements and 0.98 for manual measurements. Improved correlation was found for the estimation of VM variation after sclerotherapy using volumetric measurements (ICC=0.85) compared to manual measurements (ICC=0.45). No difference in perfusion percentage was found between success or failure (p=0.2). Conclusion Volumetric assessment of VM at baseline is as reproducible as manual measurement of mean diameters. However, volumetric assessment of VM is more reproducible than 2D measurements to evaluate clinical response following sclerotherapy. Perfusion analysis of VM have no correlation with better clinical successes.