P772 Investigation of proximal tubule functions in a model of renal Fanconi syndrom by 99mTc-DMSA, 99mTc-MAG3 and 123Ibeta2-microglobulin SPECT on conscious mice F. Jouret, S. Pauwels, S. Walrand, O. Devuyst, F. Jamar; Univ Catholique de Louvain, Brussels, Belgium. Aim: Animal models of kidney diseases are usually studied ex vivo, with clear ethical and technical obstacles. In vivo imaging techniques is an attractive alternative for clearance and biodistribution studies. We report on SPECT for PT function assessment in Clcn5 knockout mice, an established model of renal Fanconi syndrome.Materials and Methods: All procedures were performed on conscious mice smoothly placed inside the small-animal SPECT device (Linoview systems, Amsterdam, the Netherlands). 99mTc-DMSA (25MBq) static SPECT (5min) was obtained every hour during 6 hours after iv injection. 99mTc-MAG3 (22MBq) and 123I-ȕ2microglobulin (7MBq) dynamic SPECT (15sec) were acquired continuously for 30 minutes after iv injection. In 123I-ȕ2-microglobulin study, urine was analyzed using silica gel chromatography.Results: In control mice (n=4), 99mTc-DMSA SPECT showed standard uptake curves (plateau phase at 6 hours), with a clear delineation of kidney cortex. At 6 hours post injection, 99mTc-DMSA uptake in Clcn5Y/+ was 9.8% ± 0.4 ID/kidney (n=4), but was completely abolished in Clcn5Y/- mice (0.4% ± 0.1 ID/kidney, n=4). 99mTc-MAG3 studies showed no difference between Clcn5Y/+ (n=5) and Clcn5Y/- mice (n=5). The maximal uptake of 123I-ȕ2microglobulin was ~7% ID/kidney (at 7 min) in Clcn5Y/+ mice with the activity located over the cortex (n=2), compared to ~3.5% ID/kidney (at 2 min) in Clcn5Y/- with the activity restricted to the pelvis area (n=2). In Clcn5Y/- mice, the curve was typical of strict glomerular filtration without tubular reabsorption, and urine analyses confirmed the loss of intact 123I-ȕ2microglobulin.Conclusions: SPECT analysis has invaluable benefits for the in vivo investigation of PT functions: (i) absence of animal sacrifice, (ii) biodistribution studies of distinct radiotracers in the same animal at different time points, (iii) achievement of acute and/or long-period monitoring, allowing pharmacokinetic studies. 99mTc-DMSA results suggest a basolateral dysfunction of the co-transporter NaDC3 in Clcn5Y/- PT cells. Comparative capture of 123I-ȕ2microglobulin demonstrate a severe defect in PT apical endocytosis in Clcn5Y/- kidneys, whereas 99m Tc-MAG3 data show no alteration of the secretory pathway in ClC-5 deficient mice.

P773 Assessment of cell-specific radioisotope gene therapy effect with concomitant optical reporter gene transfer B. Ahn, M. Ryu, J. Yoo, J. Lee; Kyungpook National University, Daegu, Republic of Korea. Objectives: Cell specific killing can be achieved by therapeutic gene activated by a specific promotor, such as, AFP enhancer. Degree of therapeutic gene over-expression by the specific enhancer is a major component for specific cancer killing effect, and it can be assessed by the cotransfection of other reporter gene. This study was performed to construct a recombinant adenoviral vector carrying both a therapeutic sodium iodide symporter (NIS) gene activated by AFP enhancer and optical reporter fluorescence protein (GFP) gene activated by CMV promoter for targeting AFP producing hepatocellular carcinoma.Methods: AFP enhancer, selected by PCR technique with genomic DNA, fused with NIS gene was fused to pAdTrack-CMV with GFP gene. A recombinant adenoviral vector, carrying both NIS gene activated by AFP enhancer and optical reporter gene GFP activated by CMV promoter, was constructed with the AdEasy system. Hepatoma cell(HepG2) was transfected with the adenovirus. Expression of the NIS gene at mRNA level was elucidated by RT-PCR and western blot and GFP expression was also evaluated with fluorescence microscopy.Results: AFP enhancer was successfully synthesized. NIS gene with AFP enhancer were directly inserted into pShuttle and pAdTrack with GFP gene. These insertion of the target gene to shuttle vectors were confirmed by restriction enzyme digestion and DNA sequencing technique. NIS expression gene of the transfected hepatoma cell was confirmed with RT-PCR and western blot and GFP expression was also confirmed with fluorescence microscopy.Conclusions: We constructed a recombinant adenoviral vector system carrying both the therapeutic NIS gene activated by a AFP enhancer and a reporter GFP gene activated by CMV promoter. This adenoviral vector system can be used as a specific therapy for the AFP producing carcinoma and the effect of radioiodine gene therapy might be assessed by a optical imaging technique.

P774 Methodology for analysing sequential 3D SPET scans of patients following unsealed source therapy for bone metastases D. Binnie1, A. Divoli2, R. V. McCready3, G. Flux4; 1Institute of cancer research / Imperial college of Science Technology and Medicine, Sutton / London, United Kingdom, 2Institute of cancer research, Sutton, United

Kingdom, 3Institute of cancer research / Hammersmith hospital, Sutton / London, United Kingdom, 4Institute of cancer research, Royal Marsden Hospital Foundation Trust, Sutton, United Kingdom. Introduction and Aim: A previous study evaluated planar images scans following high activity rhenium 186 therapy for bone metastases from carcinoma of the prostate and noted a significant difference in retention between lesion and normal bone. The aim of this study was to develop a method for three dimensional analysis of SPET bone scans post therapy which takes care of misalignment between sequential scans and follows the spine considering the curvature without the need for prior registration. The study also evaluated the differences in the analyses of the planar and SPET techniques with the long-term aim of improved quantification.Materials and Methods: A series of planar or tomographic images were acquired at five time points, from 0.5 to 72 hours, for patients following high activity 186Re-HEDP therapy. In this technique raw data are first reconstructed using filtered back projection (FBP) and also an iterative method (OSEM). Space points are created at a sequence of locations along the spine. The first three define a curvature in a plane; additional points are connected to the end to form a smooth trajectory along which position and direction are well defined. An ROI is formed by a thin, 8 voxel radius disk (voxel dimension 4.6mm) drawn in a plane normal to the trajectory and is systematically moved, step-by-step along the spine to produce activity profiles and hence tumour to normal uptake can be compaired, or total counts within a lession obtained.Results: In spite of the increased background anticipated for the planar images, the SPET images are considerably noisier. The two reconstructions gave similar activity profiles, higher resolution with OSEM. The size of the ROI disk helps to smooth out fluctuations and artefacts. From a detailed study of the comparison, the reconstruction is estimated to introduce about 2 to 3 times the error expected from statistics alone. Visualising the full length of the spine in a single image was a significant advantage for planar images as SPET images are limited to the field of the gamma cameraConclusions: The method described allowed the analysis of 3D sequential SPET images, following curvature without the need for prior registration. The SPET images had improved resolution over the planar images with the disadvantage of extra noise. However the technique will prove valuable in the quantitative analysis of bone kinetics of metastases and normal bone to explain the differential response of lesions to Re 186 HEDP therapy.

P775 Co-infusion of DTPA during peptide receptor radionuclide therapy with In-111 DTPA Octreotide reduces the ionic indium-111/114m contaminants G. S. Limouris1, L. Lamprakos2, D. Kontogeorgakos2, P. Sideras2, C. Panayides2, K. Rousopoulos2, P. Dimitriou2, M. Lyra2, A. Stavraka2, L. Vlachos3; 1University of Athens, Athens, Greece, 2University of Athens, Aretaieion Hosp, Radiology Dept, Nucl Med Div, Athens, Greece, 3 University of Athens, Aretaieion Hosp, Radiology Dept, Athens, Greece. Aim: Peptide Receptor Radionuclide Therapy (PRRT) in man is being performed routinely in our Institution with In-111 DTPA Phe-Octreotide (Octreoscan, Mallinckrodt, Petten), mainly in neuroendocrine cancers, positive for somatostatin sst2 receptors after selective catheterization of the hepatic artery. The radiopharmaceuticals according to the manufacturer contains radiocontaminants trivalent free ions of In-1113+ ( T P1/2 = 2.83 d ) and In-114+3( T p1/2 = 49.5 d ) free ions ( 0.1 % ). However since a mean patient dose per session usually ranges from 4070 MBq ( 110 mCi ) to 7030 MBq ( 190 mCi ) ( ! ) the amount of free In-1113+ and In-114+3 could provoke indesirable radiological burden to the patient. By the present it was aimed to reroute the ionic indium fraction to renal clearance.Materials and Methods: 18 patients with neuroendocrine disease, age range 26 to 72 yrs, treated after selective hepatic catheterization were included in the study. Nine out of them received a DTPA (Bristol-Mayers Squibb) co-infusion in a dosage of 20 mg in 500ml normal saline solution. Quantification of whole body scintigrams (30 min, 24 and 48 hrs p.i) was performed [MIRD Pamphlet No. 16 (J Nucl Med 1999, 40: 37S-61S )]. Urinary and blood samples collection and measurement during the patients’ hospitalization were done using a well type scintillation counter.Exposure rate measurements at 1m distance from the patient were accomplished by means of a ionization chamber. The dose was estimated according to the MIRD schema [MIRD Pamphlet No. 5 ( revised J Nucl Med 1978 )].Results: The activity and exposure rate half lives ( hr ) in blood were 2.2 +/- 0.4 and 1.2 +/-0.5 ( rapid phase ) without and with DTPA respectively (p<0.05) whereas for the slow phase was 14+/-8 and 12+/-5 (p>0.05). For the whole body the rapid phase was 11+/-3 and 8.1+/-1.2 (p<0.001) without DTPA and with DTPA respectively. For the whole body (slow phase) was 33+/-12 and 33+/-11 (p>0.05).Conclusions: The DTPA co-infusion enhances the rapid clearance of 111In leading to the optimization of radiation protection of the clinical staff, the members of the family as well as those of the public. It is obvious that the efficacy of DTPA co-infusion in PRRT significantly reduces the radiobiological burden for the benefit of the patients, contributing to the optimization of the treatment (97/43 EURATOM Directive). Consequently it is strongly recommended in every PRR T.

Technologists Posters TP01 — Monday, October 02, 2006, 8:00 am - 9:30 am

Technologists Posters 1 – Foyer at Mitropoulos TP01 Quantitative assessment of myocardial 123I-BMIPP uptake in patients with ischemic and non-ischemic heart failure M. Sasaki, H. Kawai, H. Ishikawa, H. Kubono, T. Toriyama, T. Okado, S. Tanaka, F. Suzuki, H. Takase; Enshu General Hospital, Hamamatsu, Japan.

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Poster Presentation

treated with cationic reverse-phase vesicles (REVs) encapsulating 111In-labeled antisense oligonucleotides (average specific radioactivity of vesicles was 40 MBq/2 nmol of oligonucleotides/µmol of total phospholipids) that had an average diameter of 250 nm. Hybridization of the radiolabeled oligonucleotides with N-myc mRNA, N-myc expression, and cell proliferation were investigated. The tumorigenicity of treated cells was analyzed in nude mice. Non-radiolabeled antisense and 111In-labeled sense oligonucleotides were employed as controls. Results: 111In-labeled antisense, which hybridized with N-myc mRNA, was detected in cells at 12 and 24 hrs after the initiation of the treatment. Reduced N-myc expression and inhibited cell proliferation were shown in the same cells at 48 hrs after the completion of treatment. N-myc-suppressed cells continued to produce intraperitoneal tumors in nude mice, although the average weight of the tumors was lower than that of tumors in control mice. Conclusion: Auger electrons emitted from 111In in close proximity to their target N-myc mRNA may prolong the time to cell proliferation in human neuroblastoma cells that have overexpressed N-myc. Auger electron therapy therefore has potential as an internally delivered molecular radiotherapy targeting the mRNA of a tumor cell.

Aim: Myocardial scintigraphy using 123I-BMIPP has been used for evaluation of various cardiac disorders including ischemic heart diseases and cardiomyopathy. We investigated whether quantitatively calculated myocardial uptake of 123I-BMIPP was associated with parameters obtained from echocardiogram in patients with chronic heart failure.Materials and Methods: Consecutive 124 patients (men/women=74/50, age 71±13 years, ischemia/nonischemia=45/79) with chronic heart failure were enrolled. In stable condition under adequate medications, 123I-BMIPP scintigraphy was performed and myocardial uptake of 123I-BMIPP was calculated using the Ishii-MacIntyre method. At the same time, echocardiogram was performed and blood was sampled for the measurement of brain natriuretic peptide (BNP) (Shionoria BNP kit, Shionogi, Japan).Results: Myocardial uptake of 123I-BMIPP was significantly higher in men rather than in women (1.70±0.54 vs. 1.39±0.43%, p=0.0008), while there was no difference between ischemic and non-ischemic patients (1.55±0.33 vs. 1.59±0.60%). Myocardial uptake was significantly correlated with BNP (r=0.344, p=0.0096), and intraventricular septal thickness (r=0.474, p<0.0001), left ventricular posterior wall thickness (r=0.503, p<0.0001) and left ventricular mass (r=0.498, p<0.0001) obtained from echocardiogram in patients with non-ischemic, but not ischemic heart failure. There was no significant correlation between myocardial uptake of 123I-BMIPP and age, left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter or left ventricular ejection fraction.Conclusions: In patients with non-ischemic heart failure, quantitative myocardial uptake of 123I-BMIPP is associated with left ventricular mass and reflects the severity of heart failure. This method may be useful for quantitative analysis of patients with non-ischemic heart failure.

TP02 Left ventricular ejection fraction determination using planar gated blood pool: comparing four different operator’s results M. A. C. S. Martins, M. D. M. Cardoso, M. M. L. Parracho, F. M. P. B. Conde, I. A. C. Q. Ferreira, A. A. Ferrer-Antunes, J. M. C. Pedroso de Lima; Hospitais da Universidade de Coimbra, Coimbra, Portugal. INTRODUCTION AND OBJECTIVES: The planar Gated Blood Pool study is an important tool in the evaluation of Left Ventricular Function, whether global or segmental, when there is the need to evaluate the functional reserve and toxicity of the cardiac fibre, in patients submitted to chemotherapy or with isquemic and hypertrophic myocardiopathy among others. In order to maintain a high confidence level in this study, it is important to eliminate every parameter that might increase variability of results. The aim of this investigation is to compare values of obtained by planar Gated Blood Pool and determined by 4 different operators, using a semiautomatic processing method.Materials and Methods: Planar Gated Blood Pool images were obtained using red blood cells labelled in vivo with 99m Tc. 150 patients with an average age of 56.85 ± 30 years, 86 men and 64 women were imaged using a single-head camera, equipped with a low-energy and high resolution collimator. Patients were positioned supine and planar gated imaging was performed in the best septal left anterior oblique projection. Images were acquired as 64 64 matrices, zoom 1.6, gated for 24 frames per R-R interval in a total of 500 cycles. All images obtained were analysed by four different operators at different time. Mean values and associated standard deviation of all 4 samples were established; paired t tests were used to assess whether means of calculations were different between the two different methods and linear correlation coefficients (r) and regression straight lines determined.Results: The applied imaging processing methodologies deserve special attention, since they seam to be relevant when close values are involved. All the values obtained were validated with statistical analysis methods, presenting no significant differences between most of the operators involved in this study. However, the results of one of the operators involved screened a low correlation level with all the others, denoting the existence of some degree of variability. The analysis of the results and the findings evidenced in this report allow emphasising the discussion and comparative evaluation between operators, concerning processing methods of planar Gated Blood Pool studies.Conclusions: The planar gated blood pool is an effective, non invasive, relatively cheap and easy to apply technique in determining left ventricular function. The present data emphasize the need to establish meticulous processing methods, eradicating every action among operators that might increase variability of results, in order to optimize the technique’s results.

TP03 18

F-FDG-PET in diabetes mellitus(DM) patients: the earlier the better

C. Feenstra, P. A. Doodeman, R. A. Valdes Olmos, C. A. Hoefnagel, M. Sonneborn; The Netherlands Cancer Institute, Amsterdam, The Netherlands. Aim: Patient preparation for 18F-FDG oncologic tumor imaging with PET is very important for obtaining quality images. At the Netherlands Cancer Institute a different preparation is used for patients with Diabetes Mellitus because of the risk of hypoglycemia. In a previous study we observed increased uptake of 18F-FDG in the bowel in DM patients. In the present study we compared the degree of bowel activity in DM patients scheduled in the morning (7.00-12.00) and patients scheduled in the afternoon (12.15-16.00) in order to optimise the protocol in DM patients.Methods: In 2004 and 2005 70 DM patients visited our department for an 18F-FDG-PET. 32 Patients were planned in the morning and 38 in the afternoon. Those who came in the afternoon could have a light breakfast. The fasting time was at least 4 hours. All patients had to drink a litre of water (or tea or coffee without sugar or milk) in the two hour-period before injection of 18F-FDG. In all patients BGL was measured just before the injection. The images were evaluated according to the degree of bowel activity: 1 = low, 2 = moderate and 3 = intense bowel activity.Results: All DM patients had a BGL lower than 11,2 mmol/l, with an average of 6,1 mmol/l (morning-group 6,7 mmol/l and afternoon-group 5,6 mmol/l). In the morning-group bowel activity was: 1 (low): 8 (25%), 2 (moderate): 15 (47%), 3 (intense): 9 (28%). In the afternoon group: 1: 10 (26%), 2: 8 (21%), 3: 20 (53%). No other differences in the images were seen between the 2 groups.Conclusions: In DM patients with comparable BGL and preparation a more intense bowel activity was observed when FDG-PET was performed in the afternoon. This may difficult adequate evaluation of abdominal malignancies. Based on the mild bowel activity observed in the early hours we recommend to schedule DM patients in the morning.

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TP04 Impact of acquisition time on diagnostic image quality in PET-scanning. N. Tietgen1, H. Blom2; 1Herlev Hospital, University of Copenhagen, Herlev, Denmark, 2Herlev Hospital, Univercity of Copenhagen, Herlev, Denmark. Background: Acquisition time in PET-scanning can be variable. Prolonging the acquisition time will in theory produce better image quality and lower throughput. Prolonged scan time is inconvenient for the patients and may lead to motion artifacts. Therefore the balance between the shortest scan time and the best image quality is to be established. Aim: To assess the effect on diagnostic image quality using 2 and 3 minutes per acquired bed position. Methods: 19 patients (6 females) with different types of cancers were consecutively included in the study. Mean age 55 years (33 - 69), mean high 173 cm (153 - 194), and mean weight 73 kg (45 - 100), BMI 18 30, mean blood sugar 5.6 mmol/l (3.7 - 6.6). 370 MBq F18-FDG was injected after 5 hours of fasting. After one hour rest, acquisition of the transmission and the emission scans were performed using a combined PET/CT system (Gemini, Philips). The PET scans were performed twice: In 17 cases the 3 min study were performed first. Two experienced specialist in nuclear medicine evaluated the images with respect to diagnostic quality without knowledge of acquisition set up. Data were analyzed for the total group of patients and re-analyzed with the patients separated in two groups with BMI = 25 as discriminator. Results: In 10 of 19 cases the physicians agreed that the quality of the 3 min images were superior to the 2 min images. BMI was above 25 in 11 patients (3 females). Among these 11 patients the physicians agreed that the 3 min images were superior compared to the 2 min images in 5 cases. Among the lean patients the physicians agreed that only 1 of 8 studies showed superiority of the 3 min images. Conclusion: In patients with BMI > 25, 3 min acquisition time per bed position has superior diagnostic quality compared to an acquisition time of 2 min per bed position. In patients with BMI < 26 image quality is equally good using an acquisition time of either 2 or 3 min per bed position. Further studies should be acquired for confirmation.

TP05 Conicidence PET with triple-head gamma camera using F-18 FDG in oncolgy B. Oresic, D. Grosev, Z. Jurasinovic; University Hospital Zagreb, Zagreb, Croatia. We are using F-18 FDG coincidence PET in oncology from 2000. Until March 2006 160 patients were examined using this method. Our Clinical Department cannot produce F-18 FDG on-site since we don't have a cyclotron unit, so we receive F-18 FDG shippment once a week from the production site in Siebersdorf, near Wienna, Austria. In order to obtain desired amount of activity, we have to order larger quantity than needed to compensate for the rapid decay of the radiofarmaceutical. We receive 4810-4995 MBq (130-135 mCi) of F-18 FDG, and four to five patients are scheduled for the exam. Phillips (former Picker) triple-head IRIX gamma camera is used, aquipped with 3/4 inch sodium iodide crystal and axial filters (scatter frames). Using axial filters as a sort of one-dimensional collimation and three heads increases system efficiency, enables dose reduction and shortens the aquisition time. Two bed positions are used to acquire tomographic images of neck, thoracic, abdominal and pelvic regions, which lasts for about an hour. The most frequent refferal diagnosis in our population was lymphoma, both Hodgkin and non-Hodgkin (76 patients, 47.5%), sarcomas (15 patients, 9.4%), breast cancer (9 patients, 5.6%), melanomas (8 patients, 5%), tumors of unknown origin (10 patients, 6.3%), and all the other tumors (lung, testicular, rectal, renal, pancreatic, gastric, GIST, thyroid, neuroblastoma) accounted for the rest of the cases (42 patients, 26.2%). Our experience shows that PET coincidence imaging can be performed in departments that doesn't have dedicated PET camera and/or on-site production facilities, provided the cyclotron unit is available within reasonable distance and additional organisation effort is invested.

TP06 PET-FDG with anesthesia (sevoflurane-N2O) in oncological paediatric patients. Nursing management. S. Lopez Gandul, G. Perez-Moure, J. Garcia, M. Soler, M. Simo, J. Moncho, F. Lomena; CETIR GRUP MEDIC, Barcelona, Spain. Introduction: The number of oncological PET studies has increased remarkably. In some of them, the impossibility to maintain children collaboration during the acquisition of the images requires a general anesthesia. Aim: To describe nursing management of the oncological paedriatic patients who underwent to FGD-PET with anesthesia.Materials and Methods: : Whole body FDG-PET scans were performed from January 2002 to December 2005 in 36 paediatric patients, referred to our department to ruled out cancer disease. The children parents were informed on the procedure of the test. All patients were fasting between 4-6 hours before FDG injection. Oral hydratation was not made due to anesthesia protocol. Anesthesia criteria: 1. Patients under 5 years; 2. Previous history of no collaboration in diagnostic test; 3. Nervousness/Anxiety; 4. Neurological disease 5. Nuclear physician decision. An abbocath (25G) was placed in the vein and FDG (0.25 mCi/Kg) was administrated at rest, without anesthesia trying to not interfere in the cellular FDG incorporation. Nursing professionals tried to keep a relax atmosphere to reduce muscular uptake tracer, during 45 minutes. General anesthesia using sevoflurane-N2O was performed by an anaesthesiologist, just 5 minutes before the beginning of the tomographic acquisition. PET-FDG studies were performed with Advance NXi GE starting by transmission scan, to reduce anesthesia duration. The patient was kept under TV surveillance and the oxygen saturation and rate cardiac beating were monitoring during the anesthesia by nursing personnel.Results: Of the 36 oncological paediatric patients, 9 (25%) required general anesthesia using sevoflurane-N2O. 6/9 due to be children under 5 years and the others 3/9 due to inclusion criteria. All of them showed an optimal quality of corporal image. Only 1 patient showed muscular stress uptake. Two patients mobilized the head during the acquisition, obtaining a brain

TP07 PET scanning and attenuation correction with 137-Cs versus Low Dose CT, in obese patients. C. W. Skøtt, S. Holmboe, L. Jeppson; Herlev, Denmark.

Herlev Hospital, Copenhagen,

Aim: To evaluate a 137-Cs rod source versus Low Dose CT (ldCT) for attenuation correction of PET emission data in obese patients. The end point was image quality judged by specialists in nuclear medicine. Background: Attenuation correction is difficult in obese patients. Philips Gemini PET/CT scanner is equipped with a 137-Cs rod source (fan beam) and CT scanner for transmission scanning and attenuation correction. In theory it cannot be predicted which method should be chosen in obese patients. From an “energy point of view” the 137-Cs-source is expected to give superior image quality. However, ldCT is expected to give superior image quality from “particle flux point of view”. The average duration of PET-scanning with ldCT attenuation correction is 20 minutes. 137-Cs-transmission scanning adds 10 minutes to the scan time.Methods: 26 patients (17 males), mean age 60 years and mean BMI 33 kg/m2 (range 28 - 44 kg/m2) were examined using the Gemini PET/CT scanner. After 5 hours of fast, an intravenous injection of 370 MBq 18F-FDG was administered if blood glucose values were below 8 mmol/l. Subsequently, the patients rested for 60 minutes. The PET/CT-scan was initiated with a CT surview followed by a ldCT (40 mAs, thickness 6.5 mm, increment 5 mm). Finally, the PETemission scan was performed (2 min. per bed position) followed by the Cs-transmission scan (38 sec. per 137-Cs rotation). The emission scan was reconstructed with ldCT and 137-Cstransmission scan. The two sets of attenuation corrected PET-scans were reviewed by two experienced specialists in nuclear medicine who were blinded to the attenuation correction method. They were asked to decide which of the images they preferred to use when making diagnosis.Results: Specialists A preferred 62 % of the scans reconstructed with ldCT. In 38 % neither method was preferred. Specialists B preferred 30% of the scans reconstructed with ldCT and 27% of the scans reconstructed with 137-Cs rod source. In 43 % neither method was preferred. Between the two specialists, there was concordance in 30 % of the cases with ldCT. Their agreement in the equal quality was 38 %.Conclusions: In 73% of the studies the specialists agreed that the two methods for attenuation were equal in quality or that the ldCT corrected images were superior to the 137-Cs corrected images. In conclusion the use of 137-Cs for attenuation correction in obese patients dose not improve image quality. ldCT is beneficial as anatomic mapping.

TP08 Sentinel lymph node scintigraphy in patients with malignant skin melanoma T. Mikulic, T. Samardzic, Z. Jurasinovic; Zagreb, Croatia.

University Hospital Zagreb,

We started performing sentinel lymph-node scintigraphy in patients with malignant skin melanoma in July 2000, and until March 2006 we examined 105 patients. The examination in usually performed after biopsy, and on the morning when a wide skin excision and/or grafting is scheduled. Senti-Scint (Medi-Radiopharma Ltd, Hungary) is used as radiofarmaceutical, and the standard dose of 37-55.5 MBq (1-1.5 mCi) of this Tc-99m labelled human serum albumin colloid is contained in 0.3-0.5 mL. This volume is devided and injected intracutaneously around the biopsy scar, usually in four locations. After the administration of the radiofarmaceutical the dynamic study is initiated. 45 frames by 60 seconds are obtained, followed by static study that lasts for 5 minutes. We are using large field of view gamma camera fitted with low-energy allpurpose parallel collimator, and image matrix 128x128x16. If a sentinel lymph node is visualized at the end of the study, it is marked with waterproof marker on the skin using both gamma camera and gamma-probe (Neoprobe Neo2000). If no lymph nodes are to be seen after the initial study, another static image is done after one hour, and repeated until the sentinel lymph node visualisation. The same gamma-probe is than used during operation to precisely localize detected sentinel lymph node and to measure it outside the body after the excision. The majority of our patients had lesions situated at the back (38 patients, 36.2%), legs (19 patients, 18.1%) and arms (5 patients, 4.8%), while 43 patients (40.9%) had melanomas in all the other locations (head and neck, groins, toes, gluteal, pectoral and abdominal region). Histological analysis of sentinel lymph node facilitates early detection of metastatic process and enables initiation of the adjuvant treatment, which gives patient a better chance for survival.

TP09 Sensitivity and resolution improvement in Sentinel Node imaging V. Fidler1, S. Škaliþ2, K. Škaliþ2, S. Fidler3, S. Dražumeriþ2, M. Prepadnik1, M. Medved1, B. Vidergar-Kralj2; 1Xlab Research, Ljubljana, Slovenia, 2 Oncology Institute, Ljubljana, Slovenia, 3Faculty of Computer and Information Science, Ljubljana, Slovenia. Introduction Real-time display of contrasted and fused scans during the study performance is a crucial one for the accuracy of Tc-99m colloid detection in Sentinel nodes. Aim Improvement of the method’s sensitivity and resolution of Sentinel nodes by decreasing the camera-patient distance and by using variable logarithmic-density transform in the image displaying. Methods During the acquisition of the Tc-99m colloid in the early and late accumulation phase and in the labeling procedure the acquisition, processing and displaying software must perform the following basic task for the optimal visualization: sorting the incoming positional signals into the image matrix and transforming it into the most contrasted display image. A fast algorithm was developed for the computation of the transformed image in the logarithmic density scale. The dimension of the density matrix, change of the threshold from the average and the colour scale

are user definable. For labeling procedure the logarithmic density image of the well defined functional image (acquired at least 5 minutes) is combined with the short time positional image (strong point source is searching the Sentinel node in close contact with the patient's skin) in such a way that the only point source density alone is displayed on the top of the functional image and a special labeling device with point source and labeling pen was constructed and used to decrease the patient to camera distant. A physical phantom simulating patient study with a set of point sources (from 0.05 to 10 ‰ of the »tumor« activity embeded in 3 and 10 cm thick overlying tissue equivalent scattering material) was used in the sensitivity and the spatial resolution assessment. Results In the phantom study we were able to reliably detect point source with activity above 0.15 ‰ of the tumor activity close (2 cm) to it and above 0.1 ‰ 10 cm away with 3 cm of scattering material. By increasing the depth of the scattering material to 10 cm the sensitivity worsened for twice. Using special labeling device improves the spatial resolution for at least twice. Besides those better visualization features the new methodology speeds up the scanning procedure and protects the patient and personnel from the lead embedded strong point source radioactivity. Conclusions Logarithmic density scale transform, fusion technique and the special labeling manipulator considerably improve basic physical features of Sentinel node imaging.

TP10 Skin marks in sentinel node scintigraphy with a dual head gamma camera - procedure optimisation I. Salminen, M. Jokinen, K. Keskitalo, L. Långbacka, T. Palmroth, M. Walldén, I. Sippo-Tujunen; Helsinki University Hospital Jorvi, ESPOO, Finland. Aim We wanted to improve the skin marking procedure in sentinel node (SN) examination. The marks should be on correct location in two projections with the patient in the same position as in surgery. We wanted to minimize the duration of the procedure as well as radiation dose for the personnel. Materials & methods We perform 250-300 SN examinations every year. We have encountered following problems: 1. There is limited space for marking the skin in a dual head gamma camera. If the patient is removed from the field of view for marking, there must be a method to measure the location of the SN. 2. In lateral imaging of breast cancer patients, patient’s arm has to be in upright position. When the arm is lowered to the surgery position, the tissue moves and the skin marks do not point correctly to a deep lying node. 3. To define patient contour, a Co-57-flood source is placed posterior to the patient. In anterior image, the source lies on detector two. In lateral image, technologist holds the source posterior to the patient during the image. 4. The patient goes directly to the surgery form NM unit. The image including marks and report should be available immediately. Results 1. To be able to mark the skin when patient is no longer under the detector, a transparent frame with grid lines, laser pointer, and reference points with Tc-99m was developed. 2. If tissue moves significantly when lowering the arm, laser pointer is used to move the skin marks as well. 3. A specific holder was developed to keep the Co-57-flood source in place in the lateral view to reduce the radiation dose to personnel. 4. After the exam, the report is typed as an annotation to the image. The result is printed and skin marks added manually to the print. The technologist takes the report with the patient the surgical unit. The image is also sent to PACS. Conclusion The skin marking procedure has been improved by developing a measuring frame with grid lines and by moving the marks when tissue moves in repositioning the arm. The radiation dose to the personnel has been reduced by a developed flood source holder. The surgeon receives the report with the patient in 15-30 minutes after the start of the acquisition.

TP11 Lymphatic clearance of human Tc-99m labelled IgG and Nanocoll after subcutaneous injection in a rabbit: Possibility for an immunoscintigraphic sentinel node model? M. R. Jensen, T. S. Lundby, L. Larsen, B. Hesse, A. H. Chakera; Rigshospitalet, Copenhagen, Denmark. Background/Aim: The use of scintigraphy and subsequent peroperative probe detection for the identification of sentinel nodes improve patient managing, morbidity and probably also mortality in cancers with lymphatic dissemination, the most important being breast cancer and melanoma. However, the examination still requires biopsy and peroperative histology or reoperation. It would be a great advantage if the sentinel nodes could be classified into benign and malignant nodes pre-operatively. Immunoscintigraphy with sub- or intracutaneous injection of specific antibodies might represent such a tool. We therefore compared lymph node clearance of a whole IgG (Tc-99m labelled HIG, Mallinckrodt) with the classical sentinel node tracer Nanocoll (GEHealthcare) in the lower extremities in rabbits.Materials and Methods: In anesthetized rabbits subcutaneous HIG were respectively injected in 2 rabbits and Nanocoll in 2 rabbits. Static images were acquired on a Mediso 1-headed gamma camera during the next 24 hours. ROIs were drawn around the injection depots in the right and left extremities, the lymph nodes viualized in the right and left inguinal regions and part of the liver. Count rates in the ROIs, corrected for physical decay, are compared for the 2 tracers.Results: The data show transport of both tracers from the injection depots towards the inguinal lymph nodes and further centrally, disappearing from the injection sites. The transport is somewhat more rapid for HIG compared to Nanocoll (HIG: 53% and 6% after 5 and 22 hrs, respectively; Nanocoll: 77% and 42%, respectively). After 5 hrs 9% of the injected Nanocoll activity is in the inguinal glands with further accumulation at 22 hrs (14%), the maximal value for HIG being reached at 5 hrs (6%), declining to 2% at 22 hrs. Both tracers show some uptake in the liver and columna, also with slight accumulation over time.Conclusions: These data show that a polyclonal antibody of the IgG type after subcutaneous injection will be cleared from sentinel nodes more rapidly than the colloids used for sentinel node imaging, unless the antibody is bound by some specific (or unspecific) binding. The study suggests that lymphatic dissemination of malignant cells of a cancer might be studied by an antibody-specific sentinel node technique. It might be possible to image with the gamma camera in a dual isotope study simultaneos sentinel node scintigraphy and, in case of malignant cells present, antibody binding in sentinel nodes. The imaging should be performed after several hours, focusing directly on the sentinel node.

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low quality images. In one patient propofol was also administered to achieve enough anesthesic deepness. No patient showed adverse effects to sevoflurane-N2O.Conclusions: Nursing cares related to oncological paediatric patients who underwent to PET-FDG with general anesthesia must be specially directed to maintain the comfort and children physical safety for the accomplishment of this complicated working environment, trying to reduce anesthesia duration to the maximum.

TP12 Techonolists and Nuclear Medicine Physicians: a successful team in the sentinel node identification i. paula, T. Coutinho, M. Fonseca, L. Pereira, L. Bastos; portugues oncologia, porto, Portugal.

instituto

The accurate identification and characterization of lymph nodes by imaging has important therapeutic and prognostic significance in patients with diagnosed cancers. Thus, it becomes crucial to have this identification before surgery. Aim: To evaluate the experience with lymphoscintigraphy and sentinel node (SN) detection in the nuclear medicine department of an Oncology Hospital.Materials and Methods: Preoperative lymphoscintigraphy in breast, melanoma, vulva and tong tumours was performed in 1300 patients from January 2003 to March 2006. 735 had breast cancer (BCa), 547 malign melanoma (MM), 10 tong tumours (TT), 2 rectal carcinoma (RCa) and 6 patients with vulvar carcinoma (VCa). Preoperative lymphoscintigraphy was performed after injection of 37-74 MBq of 99mTc nanocoloid (LYMPHOSCINT®) in a volume of 1cm3 to BCa and 0.2cm3 for MM, TT and VCa. In BCa the exam were performed either on the same day or in the day before the surgery following the protocol employed at your department; static image (256X256) in anterior and modified oblique view of the axila (the arm is in a 900 angle with the body like in the surgery) 1-1,5h after the injection. In MM, TT, RCa and VCa after the injection a dynamic acquisition were performed (128X128), 1frame/15seg, until the SN visualization, static images were acquired too. The SN was marked on the skin with a indelible pen. In some of those patients extra images were often required.Results: SN were revealed in 93,3% of cases in the BCa, 100% in MM, 66% in RCa, 98.9% in VCa and 99% un TT.Conclusions: Like in the previous study performed in 2003 at our department, the requests of SN detection continuing to growing. Is a simple procedure well tolerated by patients. The technologist has a very important rule in the correct identification of the SN, pitfalls are often a trouble and there are some limitations with the image acquisition. Careful observation of the procedures and a good coordination between technologists and Nuclear Medicine physicians explains the importance of a multidisciplinary team in the successful SN identification.

TP13 99m

Interictal/ictal Tc -SHMPAO SPET co-registered to MRI as a diagnostic tool in patients with epilepsy that are candidates for surgical therapy G. Thomsen, G. Skouboe, V. Frokjaer, R. de Nijs, G. M. Knudsen; Rigshospitalet, Copenhagen, Denmark. Aim: The main role of brain SPET in surgical therapy of epilepsy is not the diagnosis of the disease, but rather to localize the seizure focus. Subtraction of interictal from ictal SPET images with subsequent coregistration with MRI (SISCOM) is a useful diagnostic tool for identifying the epileptogenic region. The aim of this study was to demonstrate the usefulness of SPET coregistrered to MRI and SISCOM in the diagnostic workup of medically intractable epileptic patients.Methods: A total of 36 patients (12 children, mean ages 27; range 2-63 yrs) were studied. First, patients underwent an interictal study where they were instructed to relax and keep their eyes open. Prior to injection of 99mTc -HMPAO (mean 950 Mbq) patients were resting 5 minutes and for 10 min post injection. For the ictal study patients were monitored continuously by a long-term video-EEG monitoring system and at the earliest sign of seizure onset as evaluated by either clinical signs or EEG changes, (whichever came first), 99mTc -SHMPAO was injected. Typically, tracer injection was done within 5-10 sec of seizure onset. SPET scanning was performed using a three-headed IRIX SPECT scanner (Phillips Medical Systems, Cleveland, U.S.A) with high-resolution collimator (LEUHR-PAR). The total scanning time of each scan was 40 sec pr. step in total 40 steps (27 minutes). Images were reconstructed using an ordered subset iterative algorithm with a low pass fourth-order Butterworth filter and Chang’s algorithm was applied for uniform an attenuation correction. SISCOM was performed as described by O’ Brien (1998). An analysis of the added benefit of including ictal SPET, MR-coregistration, and SISCOM will be conducted with a blinded evaluator.Results: The results of the analysis of the added benefit will be presented and interictal SPET, ictal SPET, SPET co-registered to MRI and SISCOM will be illustrated as case stories.Conclusions: The combination of interictal SPET, ictal SPET, SPET co-registered to MRI and SISCOM contribute a useful diagnostic tool for patients with medically intractable epilepsy that are candidates for epilepsy surgery.

TP14 Young female patient with genetic diagnosis of Friedreich's ataxia Case Report.Usefulness of SPECT with 99mTCHMPAO in cerebellar and cortical flood evaluation. A. M. Moreci, MD1, S. Carluccio, MD1, S. Ialuna, MD1, G. Caruso, PROF.2; 1 A.O. Villa Sofia and CTO, Palermo, Italy, 2Dept. Diagnostic Imaging DIBIMEL Università degli Studi di Palermo, Palermo, Italy. Friedreich's ataxia is an autosomal recessive disease, results from mutations of a gene known as frataxin, that causes progressive degeneration of nerve tissue in the spinal cord and of nerves that control muscle movement in the arms and legs. Symptoms usually begin between the ages of 5 and 15. The first symptom to appear is usually difficulty in walking, or gait ataxia. The ataxia gradually worsens and slowly spreads to the arms and then the trunk. There is often a gradual loss of sensation in the extremities, which may spread to other parts of the body. Dysarthria (slowness and slurring of speech) develops, and the person is easily fatigued. These symptoms may be associated with heart disease as cardiomyopathy (enlargement of the heart), myocardial fibrosis (formation of fiber-like material in the muscles of the heart), and cardiac failure. About 20 percent of people with Friedreich's ataxia develop carbohydrate intolerance and 10 percent develop diabetes mellitus. Diagnose Friedreich's ataxia by performing a careful clinical examination, which includes a medical history and physical examination. Tests that may be performed include: electromyogram (EMG), which measures the electrical activity of muscle cells, nerve conduction studies, which measure the speed with which nerves transmit impulses, electrocardiogram (EKG), which gives a graphic presentation of the electrical activity or beat pattern of the heart, echocardiogram, which records the position and motion of the heart muscle, magnetic resonance imaging (MRI) look for signs of deterioration, especially loss of thickness in

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the spinal cord and computed tomography (CT) scan, look for sign of ponto celebellar and cortical atrophy. Spinal tap to evaluate the cerebrospinal fluid, blood and urine tests to check for elevated glucose levels, and genetic testing to identify the affected gene. There are few study about usefulness of cerebrale perfusion SPET study to invastigate Friedreich's ataxia. We report a case of 15 years female with specific symptoms and genetic diagnosis of Friedreich's ataxia. CT scan showed pericerebellar and cisterne della base enlargment. Cerebral SPECT with 99Tc HMPAO showed cerebellar and frontal blood flow decrease. These findings suggested reverse cerebellar-frontal diaschisis which may underlie neurological deficits.

TP15 Brain perfusion scintigraphy for brain death determination S. Rep, B. Simonic, B. Tatalovic, I. Slodnjak, J. Fettich, M. Grmek, M. Milcinski; University Medical Centre, Ljubljana, Slovenia. INTRODUCTION In patients with fulfilled clinical criteria for brain death, one of the instrumental methods is needed for brain death confirmation. Transcranial Doppler ultrasound or repeated EEG are possible noninvasive instrumental methods besides brain perfusion scintigraphy. The use of instrumental methods depends on their availability. In our country, all methods are performed and brain perfusion scintigraphy is used more often in last years. AIM Aim of our study was to review brain perfusion scintigraphic investigations performed for brain death confirmation in last two years. PATIENTS AND METHODS 41 patients, 27 male, 14 female, from 1 to 75 (average 34.7) years old, were examined. 600MBq of 99mTc-ECD (NEUROLITE®) were injected intravenously after chromatographic confirmation of >90% binding of the radiopharmaceutical. Brain SPECT was performed 30 min after application using 90 projections for 20 sec each, 128x128 matrix, 360 degrees rotation, high resolution parallel hole collimator, on Siemens Multispect II gamma camera. Special care was taken, that cerebellum and brain stem were included in the field of view. Filtered back projection using Butterworth filter of 7th order with a cut-off frequency 0.45 were used for reconstruction. Rotation images were reviewed. Sagittal, coronal and transversal slices were displayed. RESULTS In 38 patients (92.6%) there was no tracer uptake by the brain, including brain stem and the cerebellum confirming brain death. In 3 patients the tracer accumulation was detected in different areas of the brain. Eight patients (19.5%) were younger than fifteen years and in all the brain death was confirmed. CONCLUSION Brain perfusion scintigraphy allows reliable and quick confirmation of brain death. Brain perfusion scintigraphy can be accurately performed also in hypothermia and irrespective of barbiturate levels after traumatic head injury or when other methods are inconclusive.

TP16 Increased brain glucose metabolism after autologous bonemarrow mononuclear cell implantation in acute ischemic stroke. P. L. Corrêa1, C. T. Mesquita1, R. M. Felix1, J. C. Azevedo1, G. B. Barbirato1, D. Borges1, C. C. Oliveira1, M. Mendonça1, G. de Freitas2, A. Manfrim1, C. Falcão1, C. Gonzalez1, S. Alves3, R. Borojevic2, H. Dohmann3; 1 Hospital Pró-Cardíaco, Rio de Janeiro, Brazil, 2UFRJ, Rio de Janeiro, Brazil, 3Procep, Rio de Janeiro, Brazil. Aim: evaluate glucose metabolism in acute ischemic stroke patients by FDG PET after autologous bone-marrow mononuclear cells therapy. Patients and methods: nine patients (6 male) with mean age of 51.7 years (range 37 to 65 years) were admitted to our hospital with middle cerebral artery acute ischemic stroke and accepted in a voluntary basis to participate in an institutional research protocol about stem cell therapy. Five days after the stroke they received in the related middle cerebral artery 3.0x108 autologous bone-marrow mononuclear cells delivery via a balloon catheter. Two patients (1 male) were evaluated as controls and did not receive the stem cell delivery. An experienced neurologist performed neurological evaluations, including administration of the National Institutes of Health (NIH) stroke scale. The NIH stroke scale was applied at baseline and the following week. All patients were submitted to brain FDG PET utilizing a dual head coincidence gamma camera with 1-in. detectors and MRI before and one week after the procedure. Two readers rated the regional cortical (stroke area) metabolism on PET (axial FDG PET Scans). We used a subjective rating scale to evaluate the presence of cortical glucose metabolism: 0=normal metabolism; 1= mild hypermetabolism; 2=moderate hypermetabolism; 3= intense hypermetabolism and -1= mild hypometabolism; -2=moderate hypometabolism;-3= severe hypometabolism. Results: all patients presented temporal and parietal hypometabolism at the baseline in the area corresponding to the infarcted zone demonstrated by MRI. One week after the procedure, the FDG PET showed accumulation of FDG in the treated area suggesting the presence of metabolically viable cells in the infarcted area. There was a visual increase in FDG accumulation in the treated area in comparison to the baseline. The mean cortical score for the baseline FDG study was -2.28 and for the post therapy study was - 0.57 (p = 0.01). The patients not treated with the stem cell therapy did not show significant FDG accumulation change in the stroke area (baseline -2; post therapy -2; p=NS). MRI demonstrated no anatomic or signal changes suggestive of infectious process after stem cell delivery relative to baseline. One week after transplantation, all patients had NHI stroke score improvement. Conclusion: the observed increased glucose metabolic activity in the stroke brain tissue may represent cellular activity or engraftment of the implanted cells, a prerequisite for the success of cell therapy. Furthermore, the FDG PET can provide functional data of the brain’s metabolic cells response to this promising stroke therapy.

TP17 Evaluation of the nigroestriatal dopaminergic pathway 123 integrity with I-FP-CITSPET- Technical procedures - 2 years of practice in our department R. F. S. Silva; HUC, Coimbra, Portugal. Introduction: N-Ȧ-fluoropropyl-2ȕ-carbomethoxy-3ȕ{4-iodophenyl}nortropane is a cocaine analogue with high affinity to the dopaminergic transporters (DAT) located in the presynaptic neurons in the striatum of the brain. When radiolabelled with 123-Iodine, the FP-CIT molecule

TP18 Nursing team implication in post-processing analysis of PET brain imaging S. Coppens, C. Tinant, B. N. Tang, S. Goldman; Cyclotron Unit, ULB-Hopital Erasme, Brussels, Belgium.

PET/Biomedical

Aim: Post-processing analysis (PPA) of functional imaging is generally limited to research, as it was historically developed for scientific purposes. PPA of brain PET concerns multi-modality approach, quantification of signal and statistical evaluation of metabolism distribution. The aim of this study was to assess whether a specialized nursing team could, independently and routinely, accomplish various types of PPA in order to bring objective complements to clinical brain PET interpretation. Methods: PPA methods were i) PET-MRI fusion (IF) using the Syngo VD20-O software (Siemens) for refined brain tumor PET evaluation; ii) calculation of the locally developed activity volume index (AVI) that integrates metabolic volume and uptake level of brain tumors and is used for follow-up and therapy assessment (1); iii) statistical parametric mapping (SPM) for FDG-PET in various neurological conditions, as proposed in the literature. A physician specialized in PET brain imaging trained all five members of the PET nursing team for: i) production of selected PET/MRI fused images, valuable for metabolic interpretation. ii) routines leading to AVI computation for C11-Methionine-PET evaluation of brain tumors. iii) SPM evaluation of single-patient PET by voxel-by-voxel comparison to a group of 29 controls subjects, as locally developed for epileptic focus localization (2). Results: PPA did not represent a heavy workload and favored personal implication of the technologists in PET image production. Additional time spent by the nursing team to perform PPA tasks approximated 20 min/patient. Specifically: i) 100 patients, essentially with brain tumor, were evaluated by IF since June 2004. In 41 cases, IF contributed to the diagnosis refinement. ii) 67 patients were evaluated by AVI since September 2005. AVI provided objective data on tumor evolution and were always transmitted to the referring physician. iii) SPM analysis was performed in all 666 patients referred since 2000 for suspicion of neurodegenerative disorders or epilepsy. Direct impact on medical interpretation was estimated in 72% of the cases. Conclusion: The input of the nursing team may be extended to various PPA in routine clinical PET. It offers a significant and robust support for the medical evaluation of brain PET examinations. Conversely, the implication of the technologists in PPA develops their personal knowledge on the PET technique and on diverse neurological conditions. The motivational impact of technologists’ implication in PPA may contribute to the quality system of a PET unit. 1. Tang et al., J Neurooncol 2005. 2. Van Bogaert et al., Neuroimage 2000.

TP19 Patient positioning in PET-CT for blood sampling during brain acquisitions G. Radtke, R. Milovanovic, S. Pawlak, T. Berthold, V. Treyer, Dr.; Unispital Zürich, Zuerich, Switzerland. Aim: One problem with quantitative brain PET-CT acquisitions made together with additional arterial blood sampling, lies in the patient positioning, because during the PET acquisition the patient lies completely within the scanner. We searched for a ,,turn-around“ procedure which facilitates the access to the patient during blood sampling.Methods: During classical brain acquisitions with PET-CT, the patient lies supine and ,,head-first“ in the scanner. This is a problem if arterial blood sampling is necessary. As a “turn-around” procedure we’re using an additional table-extension and a cradle support which is fixed on the floor at the back of the scanner. We can now position the patient feet-first and can access easily the radial artery of the patient during brain PET imaging.Results: Using the table-extension gives us the opportunity to access the patient easily without any disadvantages for brain acquisitions. The set-up of this “turn-around” procedure is easy and fast to install for the technician.Conclusions: This method increase the safety during arterial blood sampling and increases as well the comfort level for the patient.

TP20 Assessment of spatial normalization templates and smoothing size effect using statistical parametric mapping: 99m Tc-ECD SPECT brain perfusion test-retest study in healthy subjects B. Yang1, S. Wang2, Y. Chou3, T. Su3, S. Chen2, J. Chen1; 1Institute of radiological sciences, National Yang-Ming University, Taipei, Taiwan, 2 Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan, Taipei, Taiwan, 3Department of Psychiatry, Taipei Veterans General Hospital, Taiwan, Taipei, Taiwan. Objective: In vivo stability of tracer distribution and the availability of 99mTc-ECD SPECT images for healthy individuals are critical to the successful application of regional cerebral blood flow (rCBF) in clinical neurological studies. Performance of two 99mTc-ECD SPECT scans on the same subject weeks apart (i.e., at diagnosis and at follow-up or baseline after treatment) are required for assessment of brain perfusion changes over time. The purpose of this study was to examine the reproducibility of 99mTc-ECD rCBF in healthy volunteers at rest, if the psychological or physiological state changed. Material and Methods: Fifteen healthy volunteers, stratified for gender (7 males, mean age, 26.4±3.2y; 8 females, mean age, 26.8±4.3y), were included in this study. SPECT images were acquired at 30 minutes after injection of 740 MBq of 99mTc-ECD.Two examinations of the 99mTc-ECD SPECT images were performed on each individual at rest about 2-4 weeks apart, and MRI T1 images were done between two examinations of the 99mTc-ECD SPECT images. We utilized three kinds of spatial normalization template in the outcome of statistical analysis of 99mTc-ECD test-retest study:(1) the standard SPM2 SPECT (99mTc- HMPAO) template;(2) an 99mTc-ECD SPECT template, which was composed of averaging 99mTc-ECD images previously normalized to the standard template; and (3) an MRI-based 99mTc-ECD SPECT template, which was composed of averaging 99mTc-ECD images normalized according to the deformation parameters extracted from individual MRI T1 scans. After spatial normalization, the size of smoothing filter ranging from 0 mm (without filtering) to 20 mm FWHM were performed to increase signal to noise. Statistical model of paired t-test was applied to compare paired 99mTc-ECD SPECT scans for each same subject. The changes of rCBF were significant if corrected p value was less than 0.05. Results: Test-retest of 99m Tc-ECD SPECT images showed no changes of rCBF in each template approach. In addition, the size of Gaussian filter for improving SNR was demonstrated optimal within the range of 10mm to 16mm FWHM in SPECT analysis. Conclusion: According to our test-retest study, we understood variability in the output images from repeated measurements of each same subject. Investigations of rCBF under varying input conditions, such as physiological state, could be neglected. It is important to make sure that each healthy brain is in rest state and optimal preprocessing parameter is used before we begin studying cognitive activation. Key words: Reproducibility; 99mTc-ECD SPECT; Statistical parametric mapping; Template;Smoothing filter

TP21 SPM analysis of PET brain studies with neurological disease: transmission versus CT attenuation correction. I. Castiglioni1, V. Garibotto1, M. Gilardi1, G. Rizzo1, A. Panzacchi1, D. Perani2, F. Fazio1; 1IBFM CNR, University Milan Bicocca, H San Raffaele Institute, Milan, Italy, 2H San Raffaele Institute and Vita Salute San Raffaele University, Milan, Italy. INTRODUCTION: Current generation PET/CT scanners provide co-registered functional and anatomical information and use CT data for attenuation correction (AC). Efforts have been dedicated to assess qualitative and quantitative differences between transmission (TR) and CT AC PET images, in both whole-body and brain studies and the value of using CT maps for attenuation correction has been demonstrated. For neurological PET studies, Statistical Parametric Mapping (SPM) analysis is to be preferred to qualitative or semi-quantitative regionsof-interest analyses, due to a more sensitive global assessment of PET signal changes, allowing earlier and better diagnosis of neurological pathologies. In this application, SPM method compares PET data of a neurological patient to a data-base of healthy controls, whose collection is cumbersome requiring the involvement of normal volunteers undergoing a PET scan and accurate neurological tests. AIM: Answering the question: can a data base of TR AC PET normal images be used in SPM analysis of a CT AC PET brain study? METHODS: Fifteen neurological patients were studied by a PET/CT system (GE-LS) and 18F-FDG. All patients underwent a CT, a PET and a TR PET scan. PET images were reconstructed with both TR and CT AC, and statistically compared to a previously collected data set of healthy controls for whom TR AC PET data were available. TR AC and CT AC patient images were analysed by SPM, specifically: normalized to the stereotactic space as for normal subjects, smoothed (8x8x8 mm) and statistically compared (Single-Subject, replication of conditions). Different p values (0.001
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Evaluation of factors affecting the F-FDG syntheses. TP02 — Monday, October 02, 2006, 8:00 am - 9:30 am

Technologists Posters 2 – Foyer at Mitropoulos

K. S. SINGH, J. Shukla, G. P. Bandopadhyaya; Medical Sciences, New Delhi, India.

All India Institute of

Aim: To evaluate the factors affecting the 18F-FDG synthesis.Materials and Methods: 18F-FDG was synthesized in a synthesis module (explora FDG4 chemistry module). Synthesis module

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Poster Presentation

can be used to evaluate the integrity of the nigroestriatal dopaminergic pathway. Parkinson Syndromes (PS) such as Multiple System Atrophy, Progressive Supranuclear Palsy and Parkinson Disease are characterised by degeneration of the nigroestriatal pathway. However, in clinical practice, sometimes is difficult to establish the differential diagnose between Parkinson Syndromes from other similar clinical syndromes like Essential Tremor (ET), not characterised by loss of dopaminergic cells. Aims: To explain the technical procedures, the acquisition equipment used, the acquisition protocols and the image processing methods. To describe the achieved numbers with 123I-FP-CIT SPET in our department in the last 2 years, taking into account all requested exams since 2004; the age and gender of the patients received and the visual assessment of the obtained images as normal (symmetrical radiopharmaceutical striatal uptake) or as abnormal (asymmetrical or reduced radiopharmaceutical uptake in the putamen region or in all striatum).Materials and Methods: Prior the study, the patient should avoid any drugs known to affect DAT binding and block the thyroid gland to prevent the iodine accumulation on it. After a slowly intravenous injection of 111-185 MBq of 123I-FP-CIT, the patient returned after 3-6 hours in order to perform the study. It was used a Neurocam GE with multiple detector and LEHR collimators. The step and shoot acquisition with 64 projections (100 sec/per projection) took place in a 64x64 pixel matrix, with zoom 1.0, in a 360º rotation angle and the energy window was set at 159 keV ± 20%. After the SPET acquisition, images were reconstructed through filtered backprojection method and a Butterworth filter is used. Transversal, coronal and sagittal slices were obtained.Results: Since January 2004 till December 2005, were performed 84 SPET with 123I-FP-CIT in 34 male patients and in 50 female patients. The average age of the patients received was 63±10 years. Degeneration of nigroestriatal pathway was assessed in 46 patients and in 38 patients the PS diagnosis was excluded.Conclusions: 123I-FP-CIT SPET is an effective tool that helps to discriminate PS from ET for those patients in whom the diagnosis is clinically uncertain. At the present, this procedure it is of diagnostic and prognostic value and became a part of our daily routine.

requires five chemicals [HPLC grade water, anhydrous acetonitrate (CH3CN); mannose triflate (1,3,4, 6-tetra O-acetyl-2-O-methol sulfonyl-ȕ-D-Mannophyranose), stock solution (solution of K2CO3 & Kryptofic 2.2.2.in water and acetonitrile ) and hydrochloric acid (HCL)], four trap and release columns (QMA column) and four purification columns. 99.99% anhydrous acetonitrile was used. Mannose triflate was prepared by dissolving 400mg of mannose triflate in 16 ml of anhydrous acetonitrile for four run. Stock solution was prepared by dissolving 110 mg potassium carbonate and 598 mg kryptofix 2.2.2 in 0.5 ml HPLC grade water and 19.5 ml of anhydrous acetonitrile for four run. QMA column was activated manually by pushing 10 ml of 0.5 M K2 CO3 solution followed by 10 ml of water and 20 ml of air.Results: Failure/ reduced yield 18FFDG synthesis was observed on sixteen occasions (failed synthesis=8, reduced yield=8). FDG synthesis failure was observed on three occasions due to improper activation of trap and release column and on five occasions, it was due to improper preparation of chemicals (Acetonitrile was not anhydrous to 99.99%). Reduced yield of 18F-FDG synthesis (75-90% reduction) was found to be due to use of old chemicals (5 or more days old).Conclusions: Proper activation of QMA columns, and using freshly prepared chemicals the frequency of 18F-FDG-synthesis failure could be minimized. The freshly purified actonitrile should not be used for more than two18F-FDG runs consecutively.

TP23 18

More than 10 Ci of [ F]FDG in one run L. Wouters1, T. Eriksson2, X. Franci1, J. Grigg3, M. Rosser3, J. Bergstrom2, C. Mosdzianowski1; 1GE Healthcare, Loncin, Belgium, 2GE Healthcare, Uppsala, Sweden, 3GE Healthcare, Amersham, United Kingdom. Objectives: Increasing demand of PET tracers requires an easy to use synthesizer which allows a high and reliable yield with low residual activity after synthesis. A new synthesizer has been developed, based on a disposable cassette and designed to produce most of the common PET tracers. The first tracer produced is [18F]FDG. Coupled with a GE Healthcare cyclotron, the improvements in term of yield, synthesis duration, consistency even at very high activity levels and low residual activity are presented below.Methods: The [18F]FDG synthesis is based on the Hamacher method combined with an alkaline hydrolysis on solid support. The resulting [18F]FDG is neutralized with H3PO4 to provide a formulation suitable for thermal sterilization. Once the synthesis is finished, the cassette rinsing procedure removes most of the residual activity.Results: At low activity (<200 mCi), [18F]FDG has been produced with an uncorrected yield (UY) of 73.3 % ± 2.5% (RCP>99.5%) within 23 min (n=48). At medium activity (2-4Ci), UY is not affected: 72.7% ± 2.5% (RCP>99.5%; n=18). At very high activity (> 9 Ci), UY is still not affected: 71.8% ± 2.8% (RCP>99.5% ; n=4). Highest production: With a GE Healthcare PETtrace cyclotron, a dual beam bombardment using 2 x 50µA on new Gen. II targets (1.6ml internal volume) for 200 minutes was done. This production yielded a total of 16.2Ci of 18F- @ EOB (S=225mCi/µA). Due to timing / decay and residual activity in dose calibrator, 15.2Ci was transferred to the synthesizer at SOS. 10.38 Ci of purified [18F]FDG (RCP>99.0%) was produced (69.3% EOS yield; 80.0% SOS yield). No significant radiolysis phenomenon has been observed.Conclusions: A unique combination of the GE PETtrace cyclotron with the new FASTlab system is able to produce [18F]FDG with high and reproducible uncorrected yield (>70%) at starting activity level of up to ca. 15Ci. 10.38 Ci of [18F]FDG with RCP>99.0% has been produced in one single production run. This is probably a world record. The residual activity on the cassette is below 0.5%, allowing for back-to-back runs and reducing the radiation exposure to the operator.

TP24 Extraction generator of

188

Re

D. A. Tkachuk; RPA “V.G. Kholpin Radium Institute”, St.-Petersburg, Russian Federation. Research on production of radiopharmaceuticals for therapy of some deceases including the oncological ones, is actively pursued at leading medical centers. One of the most promising isotopes in this field is 88Re. At present the main source of this isotope suitable for medical use is sorption generator. For charging such generator the 188W of high specific activity is needed which may be attained by irradiation of enriched 186W in two high-flux reactors. Therefore, the 188 Re generators are very expensive. There exist other types of generators: extraction, gel, thermic. A great advantage of extraction generator over the sorption one is that it allows to use the parent nuclide with relatively low specific activity which may be attained even on exposure of non-enriched tungsten in mean neutron flux reactor. It should be also noted that the product of extraction generator contains practically no inorganic impurities like aluminum, iron etc. Radium Institute in collaboration with IPhChE RAS has conducted investigations on development of 188 Re extraction generator. This generator is based on 99mTc extraction generator which is successfully operated over 14 years in St.-Petersburg. Rhenium is extracted in the developed generator by methylethylketone (MEK). Then the extractant is evaporated and the resultant 188 Re-containing residue is dissolved in aqueous solution of appropriate composition. A series of physico-chemical characteristics were predetermined, namely, distribution coefficients, density and viscosity of solutions. The optimal operating conditions were established. Rhenium yield is more than 85 %, its radiochemical purity - above 99 %; [[Unsupported Character р]][[Unsupported Character - Н]] values of 188Re aqueous solution lie within 6,5 7,5. 188W activity does not exceed 1·10-6 of 188Re activity. Content of stable elements is defined only by quality of aqueous solutions employed for dissolving 188Re. In this case the production cost of 188Re approximates that of 99[[Unsupported Character - м]][[Unsupported Character Т]][[Unsupported Character - с]]. This is much lower as compared to 188Re produced in sorption generator. It should be pointed out that the sole problem concerned with the use of 188Re produced in extraction generator is the presence of organic substances in end product, among them MEK condensation products in alkaline medium. In this case two compounds are formed and their relative content depends on radiation loadings. The total content of these compounds comes to only 1 - 2%. They do not extract 188Re. However, effect of these compounds on synthesis of 188Re-based radiopharmaceuticals calls for further investigation.

TP25 Production of ultra small holmium-166 poly(L-lactic acid) microspheres for microtube treatment of solid tumours

S384

R. de Roos1, M. A. D. Vente1, W. Bult1, S. Buono2, A. D. van het Schip1, J. F. W. Nijsen1; 1Dept. of Nuclear Medicine, University Medical Center Utrecht, Utrecht, The Netherlands, 2Advanced Accelerator Applications, Saint-Genis-Pouilly, France. Aim: In order to be able to deliver tumoricidal irradiation doses to liver malignancies, hence doses upward of at least 50 Gy, holmium-166 (a combined beta-gamma emitter) loaded poly(Llactic acid) microspheres (Ho-PLLA-Ms) with a mean size of 30 µm have been developed. These Ho-PLLA-Ms are selectively administered into the hepatic artery after which they will lodge in and around the tumour and irradiate the adjacent tissue. Recently, dedicated to the treatment of large inoperable liver tumours, a complementary microtube technique has been developed. Therefore, ultra small Ho-PLLA-Ms (5 µm) to be injected under high pressure through these tubes were synthesized.Materials and Methods: The ultra small microspheres were produced by a solvent evaporation method. Holmium-acetylacetonate (HoAcAc) and poly(L-lactic acid) (PLLA) were added to continuously stirred chloroform (372 g). Polyvinylalcohol (PVA) 2% was dissolved in continuously stirred water at 100ºC. The chloroform solution was then added to the PVA solution (at 20ºC) until the chloroform was evaporated. The formed microspheres were washed and collected. Microsphere size distribution was measured in a Multisizer 3 Coulter Counter (Beckman Coulter, Fullerton CA, USA). The entire production process was carried out under GMP conditions. Microsphere size is determined by the stirring speed and also by varying PLLA and HoAcAc concentrations. A stirring speed of 1000 rpm was applied, and PLLA 2.4 g and HoAcAc 4.0 g were added to the chloroform. Holmium content was determined by a complexometric titration.Results: Via this straightforward production method, in which the stirring speed was the deciding variable, microspheres with mean sizes as small as 5 µm {96% between 2-8 µm} were produced. The measured holmium content in all samples was comparable (15-18% w/w). Neutron irradiation in a high-flux nuclear reactor resulted in stable radioactive (Ho-166) microspheres.Conclusions: In order to acquire Ho-PLLA-Ms of a smaller size it is required to adjust the amounts of PLLA and/or HoAcAc and/or the stirring speed; a decreasing PLLA or HoAcAc concentration correlates with decreasing microsphere sizes, and a higher stirring speed yields smaller spheres as well. This results in ultra small Ho-PLLA-Ms which can be made radioactive for employment in novel microtube anticancer techniques.

TP26 Feasibility of high resolution SPECT imaging on conscious mice: preliminary study in kidney pharmacokinetic S. Walrand, S. Pauwels, F. Jouret, O. Devuyst, F. Jamar; Univ Catholique de Louvain, Brussels, Belgium. Aim: Pharmacokinetic in rodent models is usually studied ex vivo with clear ethical and technical limitations. Recently, SPECT, or PET, imaging of anaesthetized rodents appeared to be an attractive solution. However anesthesia has been shown to interfere with baseline physiology, and therefore could modify the pharmacokinetic parameters. This paper presents the feasibility of kidney pharmacokinetic studies on conscious mice by high-resolution SPECT.Materials and Methods: A special procedure was developed to allow sweet immobilization of conscious mice in an adapted bed placed inside the SPECT device (Linoview systems, Amsterdam, the Netherlands). Static SPECT (5min) on conscious mice (n=4) were performed every hour during 6 hours after injection of 99mTc-DMSA (25MBq). Dynamic SPECT (15sec) were performed continuously on two littermate mice during 30 min after injection of 99mTc-MAG3 (22MBq). This dynamic study was repeated 6 hours later on the same animals after anesthesia by Ketamine (100mg/kg) and Xylazine (10mg/kg). Uptake and clearance rates were obtained fitting the curves by a bi-exponential function.Results: Mouse immobilization in the special bed took less than one minute. Mice remained sufficiently quite over the acquisition period and didn’t show any sign of agitation. 99mTc-DMSA SPECT showed a clear delineation of the kidney cortex whereas no activity was seen in the pelvis. The uptake curves were similar in the 4 mice. Mathematical analysis showed that the activity uptake at 6 hours was 5% close to the steady state (10% ID/kidney). The uptake and clearance rates of 99mTc-MAG3 were similar for both mice in the conscious state (uptake: 0.28-0.32 min-1, clearance: 0.23-0.20 min-1). By contrast, after anesthesia both mice presented a dramatic increase of the uptake rate associated with a decrease of the clearance rate (uptake: 6.25-4.56 min-1, clearance: 0.054-0.084 min-1). Furthermore, uptake and clearance rates showed a significant difference between the two mice in the anaesthetized state.Conclusions: These preliminary results show that (i) fine spatial resolution can be obtained in SPECT imaging on conscious mice; (ii) Ketamine-Xylazine anesthesia significantly modifies the pharmacokinetic parameters of renal 99mTc-MAG3 handling, and increases inter-animal variance.

TP27 Severe dysphagia - an accurate diagnosis with oesophageal scintigraphy including SPECT/low dose CT. T. Heiberg, M. Nilausen, M. M. Jørgensen, J. Marving, J. Mortensen; Righospitalet, Copenhagen, Denmark. Aim: Visualisation of suspected oesophago-tracheo-bronchial reflux by radionuclide tracer technique in an 83-year-old man with cerebral stroke and on parenteral nutrition during five years before intended discontinuance of the feeding tube. The patient had persistent dysphagia.Materials and Methods: Oesophageal scintigraphy was performed with 63 MBq Tc99m Nanocolloid dissolved in apple-peach puree and given as small repeated (5 ml) spoonful, with the patient sitting in bed, with his chest in front of the gamma camera. Dynamic images were done during swallowing. Three series each consisting of 60 frames with a duration of 5 seconds, were acquired on a Philips Skylight® camera. Three hours later a static planar anterior image was acquired with the patient lying supine. Further, a SPECT/low-dose CT study was performed to precisely localize radionuclide activity retained in the thoracic region.Results: Initial dynamic images showed radioactivity in the mouth, oesophagus and stomach, but did not give any suspicion of reflux to the trachea or bronchi. The three-hour static image showed activity outside the oesophagus, and the SPECT/low-dose CT scan demonstrated activity in the trachea and both main bronchi.Conclusions: Combined SPECT/low-dose CT scanning provided a physiologic and accurate, anatomic diagnosis of oesophago-tracheo-bronchial reflux in a patient with severe dysphagia.

TP28

TP31

Preliminary evaluation of the usefulness of collimator open caliber correction in myocardial SPECT

Evaluation of the accuracy in the localization of the epileptogenic zones from spet and mri studies

H. Otake1, T. Higuchi2, Y. Hoshino1, M. Miyakubo3, T. Ishikita3, N. Oriuchi2, K. Endo2, N. Motomura4, T. Sugawara4; 1Division of Clinical Radiology, Gunma University Hospital, Maebashi, Japan, 2Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan, 3Stomatology and Maxillofacial Surgery, Gunma University Graduate School of Medicine, Maebashi, Japan, 4 Toshiba Medical Systems, Co, Tokyo, Japan.

C. Crespo1, P. Aguiar1, A. Cot1, C. Falcon2, X. Setoain3, A. Donaire4, D. Ross1, J. Pavia4; 1Universidad de Barcelona, Barcelona, Spain, 2IdibapsS, Barcelona, Spain, 3Hospital Clinico, Barcelona, Spain, 4Hospital Clinico, Barcelona, Spain.

TP29 Determination of radionuclide tracer distribution: attenuation compensation is important M. C. Nilausen, T. Heiberg, P. Christensen, B. Hesse, J. Marving; Rigshospitalet, Copenhagen, Denmark. Aim: Determination of tracer distribution is interesting in many pathophysiological studies and can be evaluated with the geometric mean (GM) of opposite views, a well-known technique that can compensate for varying depth of the emission sources but not for differences in body thickness. Calculation of an attenuation compensation (AC) matrix based on a transmission scan (TS) might be used to make a better estimate of the relative tracer distribution between compartments. The purpose of this study was to assess the effect of AC on relative blood volume distribution.Materials and Methods: We studied 7 male healthy subjects after Tc-99m red blood cell (RBC) labelling with Ultratag®-kit and whole body (WB) scan on a Skylight® Philips dualhead gamma camera. Before injection of the RBCs a TS was done with a Co-57 flood field placed on the lower detector and the “shadow” of the person registered by the upper detector. The position of the subject remained unchanged during the subsequent blood pool WB scan. The GM of simultaneous anterior and posterior images was calculated and multiplied by the AC matrix, which was calculated as the lower Co-57 flood image divided by the “shadow” image. Regions of interest (ROIs) were drawn manually on the GM WB scan encompassing WB, right liver lobe, right lung and heart, and copied to the AC WB scan. Counts in different ROIs were calculated as percentages of counts in the WB ROI.Results: Data are presented as mean values (±SD) of uncorrected/corrected percentage uptake values: Right liver lobe 5.00/6.61% (±1,37/1.82, p<0006), right lung 2.98/1.59% (±016/0.58, p<0.00015), and heart 8.10/11.84% (±1.10/2.02, p<0.0006).Conclusions: Relative radionuclide tracer distribution in different organs can be determined using the method of GM of opposite views from WB scans. Supplementary AC based on TS is crucial. In this study marked changes in relative blood content were seen in lung, liver and cardiac cavities after AC.

TP30 Effect of pixel truncation method to reduce high gall-bladder uptake in myocardial gated SPECT with Tc-99m agent assessment of left ventricular function A. Kikuchi1, M. Onoguchi2; 1Kanazawa University, Shibetsu City Hospital, Kanazawa,Shibetsu, Japan, 2Kanazawa University, Kanazawa, Japan. Aim: Myocardial gated single-photon emission computed tomography (SPECT) is an excellent low-invasive means of evaluating left ventricular function. However, accumulation of the agent used for this test in the gall-bladder and liver may reduce the accuracy of this test. The aim of this study is to identify and eliminate factors affecting the magnitude and appearance of intensity artifacts for myocardial gated SPECT using myocardial phantom with a gall-bladder and liver. Material and methods: We changed dose activity (gall-bladder:liver:heart=16:2:1, 8:2:1) with Tc-99m and distance (1-2cm) between heart and gall-bladder for each phantom, and examined. In addition, the gated Tc-99m tetrofosmin SPECT studies was performed with 28 patients. Gated projection images were reconstructed using a Butterworth filter with a cut-off frequency of 0.45 cycle/cm and order 8. Gating was performed using 8 frames per cardiac cycle with a RR interval. For data analysis, we calculated pixel count in region of interest (ROI) on the heart, and truncated to a count of 110% on the heart ROI for all gated projection data. We compared parameters of left ventricular function yielded by p-FAST, QGS and left ventriculography (LVG). Results: In the analysis for phantom and clinical studies, no significant difference depending on pixel truncation counting was observed. However, correlation coefficient of ejection fraction (EF) between p-FAST and LVG in clinical studies is 0.680 with non-truncated data and 0.689 with truncated data, respectively. In addition, improvement of unevenness for EF was observed in truncate data with p-FAST. Conclusion: Use of pixel truncation method in myocardial gated SPECT may improve each parameter for left ventricular function calculated by quantitative software.

TP32 The treatment of inoperable pituitary tumors with TATE preparation - initial results

90

Y-DOTA-

N. Szalus, G. Kaminski, Z. Podgajny, A. Warczynska, G. Zielinski, E. Dziuk; Military Insitute of Health Services, Warsaw, Poland. Introduction: The patients with inoperable pituitary tumors are treated with cold somatostatin analogs but it is not always effective. DOTA-TATE preparation is a somatostatin analogue coupled with ȕ (-) emitter 90 Y. The efficacy of the treatment is based on excessive expression of somatostatin receptors (SSTR) in malignant tumours. The aim of the study: is to assess the feasibility of treatment of pituitary tumors with 90Y-DOTA-TATE preparation. Materials and Methods: 90Y-DOTA-TATE preparation was used in 3 patients with pituitary tumor : 2 pts with acromegaly and 1 with the Nelson’s syndrome. The presence of SSTR was confirmed with use of 99m Tc-HYNIC-TATE preparation earlier. Both of these radiopharmaceuticals are produced by Polatom - Swierk/Poland. In 2 pts with acromegaly the treatment was repeated twice and 1 pts with Nelson’s syndrome was treated with the 90Y-DOTA-TATE three times ( 3,7 GBq per dose). The renal protection was provided by 10 hours infusion of 1000 ml 10% amino acids preparation with max. speed of 120 ml/h. The local Ethical Committee approval has been obtained before the study.Results: There were no serious adverse events observed after 90Y-DOTA-TATE treatment. An insignificant, transient decrease of thrombocytes and lymphocytes was noted. In patient with the Nelson’s syndrome the ACTH serum concentration increase was considered as a sign of cancer destruction and the growth hormone in patients with acromegaly decreased by about 30%. The follow-up showed the clinical improvement i.e. headache. Further doses of 90Y-DOTATATE in these patients are planned.Conclusions: 90Y-DOTA-TATE preparation is feasible and promising in treatment of inoperable pituitary tumors.

TP33 Targeted radiotherapy transplantation

for

haematopoietic

stem

cell

L. Causer, K. Orchard, M. Tristam, S. Johns, J. Langford, J. Thom; Southampton University Hospital Trust, Southampton, United Kingdom. Targeted Radiotherapy Prior to Haemopoietic Stem Cell Transplantation Radioimmunotherapy ( RIT ) represents an exciting new therapeutic option for the treatment of haematological malignancies. This paper gives a report of a phase 1 clinical study including the importance of a multidisclinary team in which a radiolabelled murine anti CD-66 monoclonal antibody (MAb) has been used to deliver additional therapy prior to haematopoietic stem cell transplantation. 20 patients have received the radiolabelled antibody in four radiation doses. Aims and Objectives of Phase 1 1. To determine the MTD of tageted radiotherapy delivered by a murine anti-CD66 monoclonal antibody labelled with Y90 and determine the dose-limiting toxicity (DLT) in patients with haematological malignancies who are undergoing haematopietic stem cell transplatation. 2. To determine the pharmacokinetics of In111 labelled anti CD66 MAb in blood, urine and specific organs. 3. To develop a dosimetry model on the pharmacokinetics of the labelled anti CD66 MAb.Methods: The murine anti-CD66 MAb was radiolabelled with tracer activity (approximately 185MBq) of In111 suitable for imaging. The antibody was administered as a single infusion over fifteen minutes. The pharmacokinetics of the radiolabelled antibody was monitored by serial blood sampling, continuous urine collection, serial quantatative whole body

S385

Poster Presentation

[Pupose]Distortion or inhomogeneity of myocardial SPECT is often discussed as one of the drawbacks of 99mTc myocardial perfusion SPECT images. This artifact is well explained by the difference of spatial resolution caused by the distance between gamma camera and myocardium. Our current study describes the successful correction of spatial resolution by using OS-EM algorithm with collimator open caliber correction software.[Materials and Methods]As an initial step by phantom study, cardiac phantoms infused with 99mTc solution were fixed and image acquisition of 360 and 208 degree were performed. Reconstructed cardiac SPECT images with and without collimator open caliber correction were also compared of cardiac phantom in patients study by using the same method.[Results]Spatial resolution was prominently improved in the images with open caliber correction. Similar improvement of myocardial SPECT images was also obtained in the clinical subjective evaluation performed by two nuclear physicians independently.[Conclusion]Collimator open caliber correction software was introduced in OSEM and its utility was confirmed. Furthere improvement of collimator open caliber correction may be expected by using closer image acquisition.

Aim: Subtraction of ictal and interictal single photon emission computed tomography (SPET) images is known to be successful in localizing the seizure focus in the pre-surgical evaluation of patients with partial epilepsy. A computer-aided methods for producing substraction ictal SPET coregistered to the magnetic resonance image (MRI) is commonly used. The aim of this work was to evaluate the registration error in localizing epileptogenic zones using SPM2 softwareMaterials and Methods: Numerical phantoms were obtained from high-resolution 3D T1-weighted MRIs of 39 healthy subjects. The cerebral region was segmented in gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) using SPM2 (http://www.fil.ion.ucl.ac.uk/spm). Interictal activity models were obtained by assigning a value of 100 to GM, 25 to WM and 4 to CSF. To obtain ictal activity models, activation spots were added to the interictal activity model over typical epileptogenic zones. Misalignment between interictal and ictal activity maps was considered by performing controlled rotations and translations of the interictal and ictal activity models. Non-uniform attenuation maps were obtained by assigning an attenuation coefficient of 0.14 cm-1 to the brain and 0.30 cm-1 to the bone. The SimSET Monte Carlo code (http://depts.washington.edu/simset) was used to obtain realistic projections from the interictal and ictal activity maps. The simulation conditions included: 1) the 39 numerical phantoms of 256x256x116 voxels, with a voxel volume of 0.94x0.94x1.50 mm3, 2) 120 projections over 360º, 128x64 pixels each, pixel size 4.42x4.42 mm2 and 3) an energy window of 126-154 kev. Approximately 8.0 million detected photons were considered in projections. Reconstruction was carried out using filtered backprojection with a Butterworth filter, cutoff 0.20 cm-1 and order 5.0. The matrix size in reconstruction was 64x64x64. Registration was performed by using the facilities implemented in SPM2. Intramodality registration between the ictal-interictal SPET was carried out by using rigid registration and the Normalised Cross Correlation (NCC) as the penalty function. Intermodality registration between the ictal image and the MRI was performed by using rigid registration and the Normalised Mutual Information (NMI) as the penalty function. Trilinear interpolation was employed. Results. The mean and standard deviation of the error of the registration routine for the 39 pairs simulated studies were (0.91±0.44) mm for translation, (3.51±1.90)o for rotation in intramodality registration and (1.91±1.01) mm and (1.87±1.23)o for intermodality registration. Conclusions. NCC and NMI are reliable penalty functions. Similar accuracy was found although a different behavior was observed in the rotation and translation errors.

and SPECT gamma-camera data. The starting radiation activity of Y-90 labelled anti-CD66 was 5MBq/kg body weight. Effect of administered radiation on blood counts, blood acitivity curves, radiolabelled antiCD-66 MAb biodistribution, organ dosimetry and toxicity post Y90 labelled antiCD-66 MAb were all measured. Results : The radiolabelled infusion was associated with a fall in total white count, neutrophil and platelet count implying a myelosuppressive effect of the radiation. The earlier In111 infusion did not result in these changes. In111 activity in whole blood shows a similar pattern between patients. Radiolabelled antiCD-66 MAb biodistribution and dosimetry were consistent with the corresponding sites of active bone marrow. The spleen, liver and vertebral bodies are visible on gamma camera imaging. These were deemed to be the dose limiting organs. No adverse effects were seen during the In111-labelled or Y90- labelled anti-CD66 infusions. There was a trend for increasing grade of haematological toxicity with total activity of Y90 infused. Time to haematological recovery and full engraftment was achieved within predicted time periods. Conclusion This study was an opportunity for nuclear medicine to work with the multidisciplinary team to provide an extra component to haematopoietic stem cell transplantation. The results so far show that it is well tolerated.

TP34 Local uptake of 131-iodine and 99m-Tc-HDP in bone metastases from differentiated thyroid cancer A. Maibaum, B. Egeler, Z. Soti, N. Czech, E. Henze, W. U. Kampen; University Hospital Kiel, Kiel, Germany. Aim Extracervical metastases occur in about 10% of patients suffering from differentiated thyroid carcinoma and these lesions are located in bone and / or the lungs in approximately 40%. Osteoblastic bone metastases may be detected both by whole body imaging after 131-iodine treatment and by conventional bone scintigraphy using 99m-Tc-HDP. Aim of this study was to analyse these bone metastases in both imaging modalities with respect to their target-tobackground ratio to decide whether systemic radionuclide therapy using 153-Sm-EDTMP or 186-Re-HEDP can be suggested alternatively or complementary to 131-iodine treatment. Materials and methods A total of 119 patients treated for differentiated thyroid cancer in Kiel University Hospital were analysed retrospectively. Bone metastases were seen in 8 patients with follicular cancer and in one patient with papillary cancer. A total of 12 lesions were easily detected by both 131-iodine and conventional bone scanning. These 12 metastases were analysed by Regions-of-Interest (ROI) technique in both imaging modalities compared to a standardized background ROI. The target-to-background ratio was calculated and used for comparison between both images. Results Bone metastases showed a very high uptake of 131-iodine with a mean target-to-background ratio of 745,7 ± 93,7. Local uptake in conventional bone scanning was significantly less with a mean value of only 48,3 ± 3,0 compared to adjacent healthy bone. Mean ratio between uptake of 131-iodine and 99m-Tc-HDP was about 15 : 1. Two bone metastases showed only a very low uptake in bone scan, thus the iodine uptake was increased 837- and 4020-fold, respectively. Conclusion Uptake of 131-iodine in bone metastases from differentiated thyroid cancer is usually very high and can be used for radioiodine treatment with a sufficient target-to-background ratio. In contrast, uptake of radiolabeled bisphosphonates used for bone imaging is considerably lower. Thus, systemic radionuclide therapy using 153-SmEDTMP or 186-Re-HEDP can only be recommended in selected patients, e.g. with nonradioiodine-avid bone metastases.

TP35 99m

Usefulness of somatostatin receptor scintigraphy with TcHYNIC-TATE in visualization of medullary thyroid carcinoma an initial study Z. Podgajny1, N. Szalus1, G. Kaminski1, W. Wieliczko2; 1Military Insitute of Health Services, Warsaw, Poland, 2Regional Hospital, Szczecin, Poland. Introducion: Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor which arises from thyroid C-cells. MTC tends to metastasise at early stage during a disease (this fact is one of the main reason for poor prognosis of this tumor). During an initial stage of the disease, an incidence of cervical lymph node, mediastinal and distant metastases occurs respectively in 7180%, 36% and 20% of MTC patients. MTC releases calcitonin and carcinoembryonic antigen (CEA). This is often used applied method in a long term follow-up after surgery (total thyroidectomy with bilateral neck lymph node and upper mediastinal dissection). However these aforementioned plasma markers could not detect the location of the metastatic lesions. Ultrasonography, CT or MRI and scintigraphic procedures base on MIBG, frequently yields no positive evidence of tumors location MTC patients. 18F-FDP PET is more sensitiv in location of MTC than CT or MRI. A result of a multicenter study shows that sensitivity and specifity of 18FFDP PET were 78% and 79%, respectively. The another method which may by useful MTC diagnostic procedure is a selective venous catheterization is another method used in. It is a sensitive and specific tool for location of calcitonin production site (however restricts its common use in practice). The newest method of detection recurrence and/or metastatic medullary thyroid carcinoma is the newest method Somatostatin Receptor Scintigraphy. The aim of study: Assessment of scintigraphy with the somatostatin analog 99mTc-HYNIC-TATE to visualization of medullary thyroid carcinoma.Materials and Methods: Three patients with reccurence or/and metastatic medullary thyroid carcinoma (all of them have persistent elevated serum calcitonin levels and positive biopsy, ultrasonography, CT or MRI) underwent neck, chest and upper abdomen scintigraphy with the somatostatine analog 99mTc-HYNIC-TATE produced by OBRI Polatom [[Unable to Display Character: Ś]]wierk/Poland. The scintigarphy image acquisition was performed with a double head gamma camera Varicam Elscint in 10min, 2-3h after i.v. injection of 99mTc-HYNIC-TATE preparation in dose 15-20mCi. The SPECT images was reconstructed with use of HERMES (Nuclear Diagnostics, Sweden) processing workstation. Results: Each patient was revealed a pathological uptake of 99mTc-HYNIC-TATE equal to or greater then normal liver tissue.Conclusions: Medullary Thyroid Carcinoma may be visualizated with 99mTc-HYNIC-TATE preparation. It may be also be used as a predictor for a radionuclide therapy.

G. Pérez Moure, S. López-Gandul, M. Simo, J. R. García, M. Soler, F. Lomena; CETIR Grup Mèdic, Esplugues del Llobregat, Spain. Objective: To compare the radiation received in a conventional Nuclear Medicine Department and in a PET unit during radioisotope manipulation, injection and patient management.Materials and Methods: Radiation absorbed doses received in hands and whole-body of 2 nurses were monitored during 20 consecutive workdays, while developed their welfare activity in a conventional Nuclear Medicine Department (NMD) and in a PET unit respectively. Three dosimeters (TLD) were used to measure radiation doses exposure: HSM (superficial equivalent dose month) and HPM (equivalent deep dose month). Two radiation dose measures were calculated: 1. Radioisotope manipulation and intravenous injection (wrist and whole body dosimeters) 2. Patient management (whole body dosimeters). The radioisotopes injected in a conventional NMD were: Tc99m, I131 and I123. And 18F-FDG was used in PET studies. We scored the number of patients injected and move to the cameras, as well as the activity doses (MBq/mCi) and radioisotope type during 8 work hours. Dosimeters lectures were done by a certified laboratory and the results were analyzed by 3 nurses, 3 physicians and 1 physicist.Results: RAD Hands injection (NM HSM:0.98mSv HPM:1mSv; PET HSM:0.99mSv HPM:1.04 mSv); RAD WB injection (NM HSM:0.21mSv HPM:0.21mSv; PET HSM:0.36mSv HPM:0.37mSv); RAD WB acquisition (NM HSM:0.19mSv HPM:0.19mSv; PET HSM:0.2mSv HPM:0.2mSv); Total mCi injected (NM Tc:10480mCi I:316mCi; PET FDG:950mCi); Number patient (NM Tc:492 I:37; PET 95); Number acquisitions (NM 300; PET 95 Delayed:23); mCi/day (NM Tc:524mCi I:15,6mCi; PET FDG:47,5mCi); mSv Hands/pat Injected (NM HSM:1.85x10-3 HPM:1.89x10-3; PET HSM:1.04x10-3 HPM:1.09x10-3); mSv WB/patient injected (NM HSM:3.96x10-4 HPM:3.96x10-4; PET HSM:3.78x10-3 HPM:3.89x10-3); mSv WB/patient acquired (NM HSM:6.33x10-4 HPM:6.33x10-4; PET HSM:2.1x10-3 HPM:2.1x103).Conclusions: Total radiation dosimetry score are similar. Even though the great difference between the number of patients injected in NMD compared with the PET unit. Whole-body radiation dosimetry lecture during the radioisotope injection was slightly higher for the PET. This fact could be related to the radioprotection devices as lead shield used in NMD (not usual in PET patients management). The 18F-FDG is much more ionizating than other radioisotopes, which explains the difference between the partial whole body radiation dosimetry during the radioisotope injection and the study acquisition.

TP37 Scintigraphic assessment of lung tumors therapy response L. Cunha1, M. F. Botelho2, A. M. Abrantes2, M. F. Baganha3, M. A. Marques3, B. Ferreira1, A. Nunes1, L. F. Metello1; 1ESTSP - IPP, Porto, Portugal, 2IBILI - FMUC, Coimbra, Portugal, 3Pneumology Department HUC - FMUC, Coimbra, Portugal. Introduction: The main reason for chemotherapy failure in cancer is nowadays identified as the presence of disseminated disease resistant to therapy. Resistance to anti-cancer drugs is a process that can overcome at any time. It can be present since the very beginning of the disease or it might appear during therapy. Therefore early identification of lack of treatment response could play a central role in the correct selection of therapeutic regimens. The goal of this work is to assess therapeutic tumor response in patients with non-surgically treated lung cancer, through the use of 99mTc-sestamibi. We studied and established relationships between radiopharmaceutical uptake, retention and elimination by the tumor and the chemotherapeutic response. Also, we studied the possibility to predict if tumors are developing multidrug resistance.Materials and Methods: Twelve patients (ages between 44 and 75 years old) with lung cancer (stages IIIB or IV) were examined twice: before and after the 3rd chemotherapeutic cycle. Anterior and posterior projections of the chest were acquired 5 and 65 minutes after 99mTc-sestamibi intravenous injection. Early and delayed uptake ratio, were calculated based on the regions of interest drawn in the images. In order to analyze the results, patients were divided in two groups according chemotherapy response.Results: We found statistically significant differences in the retention coefficient, retention index and washout rate between responders and non-responders at prechemotherapy examination. At post-chemotherapy examination we didn’t found differences between groups.Conclusions: It can be said that 99mTc-sestamibi is a useful tool to predict the chemotherapy response. However, its value in monitoring chemotherapy response during treatment is still not yet established. It will be needed to study a larger number of patients, preferentially in a multicenter approach.

TP38 Referral and authorising of renal paediatric nuclear medicine requests. Do clinical technologists get it right? R. Dakin, J. Minford, I. Jones; Derby Hospitals NHS Foundation Trust, Derby, United Kingdom. Aims:- There were 2 aims to this audit. The first was to ensure that all the paediatric renal requests received are appropriate to the clinical need and contain the relevant clinical information for the test required. The second was to check that all requests are authorised correctly by the clinical technologists. This will ensure that resources are being used appropriately and that radiation doses are being minimised to the patient to comply with national guidelines (ARSAC).Materials and Methods:- The data collection involved prospectively looking at 50 consecutive paediatric nuclear medicine renal requests received within a 12 month period. All requests were independently assessed and authorised by a nuclear medicine technologist and a paediatric consultant radiologist. Initially each request was placed into 1 of the following first 3 categories depending on the clinical history: 1. 2. 3. 4.

TP36 Comparative radiation absorbed doses study: PET unit and nuclear medicine department

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Results: 1. 2.

Appropriate (the clinical history matched the test required). Ambiguous (the clinical history was not specific enough for the test required. Inappropriate (the clinical history read as for another nuclear medicine investigation). Finally the radiologist’s and the technologist’s assessments and authorising were analysed to check for agreement. From the clinical information provided on the request card the following results occurred:35/50 (70%)requests were deemed to be appropriate.

5/50 (10%) were deemed as ambiguous. 10/50 (20%) were deemed to be inappropriate.

TP41

In all cases, there was 100% (50/50) agreement between the nuclear medicine technologist and the paediatric radiologist. Conclusions: A total of 15/50 (30%) requests received did not include sufficient clinical history to initially justify proceeding with the investigation and were returned to the referrer. This caused a delay in the patient management. The 35/50 (70%) requests that were considered appropriate had their investigation performed. All paediatric renal requests were correctly authorised by the clinical technologist and therefore no child would have undergone an unnecessary investigation involving a radiation dose.

TP03 — Monday, October 02, 2006, 8:00 am - 9:30 am

Technologists Posters 3 – Foyer at Mitropoulos TP39 Discontinuing of long-term beta-blocker therapy may falsely overestimate the fixed defects in dipyridamole myocardial perfusion imaging D. Beiki1, B. Fallahi1, S. Akbarpour1, F. Akhzari2, S. Izadyar3, J. Esmaeili3, M. Saghari1, M. Eftekhari1, A. Fard-Esfahani1; 1Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of), 2Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of), 3Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of). Aim: The previous studies suggest that acute beta-blocker administration may reduce the presence and severity of myocardial perfusion defects with dipyridamole stress. However, little information is available about chronic beta-blocker therapy. This study was designed to evaluate the effect of discontinuing beta-blocker drugs on dipyridamole myocardial perfusion imaging (DMPI) in patients who were on long-term beta-blocker therapy. Materials and Methods: One hundred twenty patients (103 male and 17 female) with angiographically proven coronary artery disease(CAD) who were being on long-term beta blocker therapy (more than three months) enrolled in a randomized clinical trial study. All patients were allocated in to group A(n=60) in whom beta-blocker was discontinued for 72 hours before DMPI and group B(n=60) with continuing beta-blocker therapy up to the time of DMPI. No significant difference was noted between two groups concerning the age, sex, type of radiotracer and number of involved coronary vessels. Images were interpreted by three observers blinded to the patients' clinical data with scoring the perfusion status using a standard 20-segment model and 3-point scaling method (as normal, reversible and irreversible segments). Correspondingly, perfusion score for each territory of major coronary arteries, left anterior descending(LAD), left circumflex(LCx) and right coronary artery(RCA), were calculated. Total perfusion scores for whole myocardium as well as each territory of individual major vessel were determined in both groups of patients. The mean ranks of perfusion scores in group A were compared with group B by Mann-Whitney-Utest using SPSS software (12.0).Results: The mean rank of total perfusion scores for whole myocardium (irrespective of reversibility or irreversibility) in group B was more than that of group A, (65.75 vs. 55.25, p=0.096). Regarding the only irreversible perfusion defects, the mean rank of perfusion score in group B was substantially higher than that of group A for whole myocardium (72 vs. 49, p=0.0001) as well as for territory of LAD (65.25 vs. 55.75, p=0.098) and LCx (70.5 vs. 50.5, p<0.0001), however; no difference was noted between two groups for only reversible perfusion defects (61.0 vs. 60.0, p=0.898).Conclusions: Discontinuing long-term betablocker therapy several days before DMPI may overestimate the extent of irreversible perfusion defects but has no effect on reversible perfusion abnormalities. As a possible reason, beta-blocker withdrawal in patients with long-term beta-blocker therapy may decompensate myocardial perfusion in rest phase, reducing the difference between rest- and stress- regional perfusion ending in falsely appearing fixed defects in the case of severe ischemia.

TP40 The reliability of clinical examination made technologist performing thyroid scintigraphy M. Vesterlund, H. Bertelsen; Aalborg, Denmark.

by

the

Aarhus University Hospital in Aalborg,

Aim: Clinical examination of the thyroid gland (size and morphology) gives valuable information for the interpretation of a thyroid scintigraphy. The clinical examination traditionally is made by the doctor describing the thyroid scan. We wanted to evaluate whether a technologist after a short training period reliably could make the clinical examination of patients referred for thyroid scintigraphy and give a tentative diagnosis from the thyroid scan.Materials and Methods: Before enrolling patients in the study a technologist was trained in palpation of the neck. This was done by a short theoretical introduction followed by examination of 20 patients together with a doctor. The study population comprised 28 consecutive patients admitted for scintigraphic examination of the thyroid gland. A technologist and a doctor independently examined the patients by palpation of their neck and made a diagnosis on the basis of the palpation and the scintigrafic result. For every patient the technologist registered whether she felt sure about the diagnosis or whether she would have called a doctor prior to the discharge of the patient.Results: In 82% (23/28) of the patients the registration of adenomatous changes by the technologist and the doctor were the same. In 1 patient the doctor noted a nodule, that the technologist did not register, and in 4 patients nodules registered by the technologist were not registered by the doctor. The size of the thyroid gland estimated by the technologist and the doctor was the same in 71% (20/28) of the patients. The interpretation of the thyroid scan made by the technologist did not differ from the interpretation made by the doctor in 82% (23/28) of the patients. The technologist evaluated that 61% (17/28) of the patients could be discharged without the need of an examination of the doctor. In none of these patients did the evaluation of adenomatous changes vary from the evaluation made by the doctorConclusions:The clinical examination of the thyroid gland of patients referred for thyroid scintigraphy can with high reliability be made by the technologist performing the scintigraphy.

Determination of the calcitonin levels in patients with medular tyroid carcinoma using an alcohol stimulation test V. Marijanovic, J. Baznik, P. Kosovic, J. Smoje, I. Mihaljevic; Department of Nuclear Medicine, Protection of the Radiation and Pathophysiology, Clinical Hospital Osijek, Osijek, Croatia. The aim of the study is to show clinical importance for determination of the calcitonin levels in the patients with medular tyroid carcinoma (MTC). Calcitonin is a polypeptide hormon, produced in the C-cells of the tyroid gland. Determination of the calcitonin concentration in the plasma has a clinical importance in both diagnosis and monitoring of the tumors that produce calcitonin.The known stimulators of calcitonin secretion are calcium in infusion, pentagastrin i.v., and alcohol per os. The most reliable and the most accepted stimulator of calcitonin secretion is pentagastrin.We have a long term experience in stimulation of calcitonin secretion by alcohol. We are using this metod because it has less side effects and it is economically acceptable. In MTC, which represents 2-10% of all tyroid tumors, calcitonin production correlates well with the stage and the size of the tumor. In the Department of Nuclear Medicine of the Clinical Hospital Osijek, determination of the calcitonin level is practiced since 1982. We have registered 45 patients with MTC, of which, 14 with the hereditary form (MEN II a) and 31 with sporadic medular carcinoma. Here, we are showing the results of the retrospective study performed on 14 patients with hereditary form of MTC and 20 patients with sporadic form of MTC. First, we have determined the basal concentration of calcitonin in the plasma of the patients . In the cases where levels were borderline or higher than normal we performed stimulation test with 50 ml of vodka (vol % 40). The blood was taken into cold vacutainers ( 5 ml/ 85 IU heparin) immediately before the stimulation and 5, 10 and 15 min after the stimulation. The immunoreacive calcitonin was measured using commercial kit (Immulite). In contrast to the healthy individuals where normal concentrations of calcitonin were detected after the stimulation, in all patients with MTC significantly higher concentrations of calcitonin were measured. On the bases of these results, we concluded that determination of the calcitonin levels after alcohol stimulation represents reliable screening test in MTC diagnosis. In addition, it is used in monitoring the post-operative state of the patients and in evaluation of the success of the treatment. Calcitonin is impecable for diagnostic purposes, since it is the most sensitive and the most specific tumor marker for MTC

TP42 Importance of determination of renin and aldosteron in captopril test P. Kosovic, J. Gardašanic, I. Mihaljevic; Department of Nuclear Medicine, Radiation Protection and Pathophysiology, Clinical Hospital Osijek, Osijek, Croatia. AIM: To show that determination of plasma renin activity (PRA) and aldosterone in captopril test is a reliable screening test for identification of patients with renovascular hypertension caused by stenosis of one or both renal arteries. INTRODUCTION: Renin is a proteolytic enzyme that is produced, deposited and secreted from the cells of the juxtaglomerular complex of the kidneys. In physiological conditions primary function of the renin-angiotensin-aldosterone system (RAAS) is the regulation of blood pressure and the metabolism of salt and water. Renovascular hypertension is caused by narrowing of the renal artery or some of its major branches, leading thus to decreased perfusion, increased tubular reapsorption, and subsequently, RAAS activation. The possibility of exact measurement of renin has been a great stimulation in studying ethiopathogenesis of different forms of hypertension. Renal angiography with determination of the separate renin values, which, because of its invasioness cannot have a widespread use, is a reliable method for diagnosis of renovascular hypertension. METODS AND RESULTS: Retrospectively, 223 patients were studied from year 1995 till March, 2006. During the preparation phase for 1-day protocol, patient had to bee still for 8 hours. Blood pressure was measured and venous blood sample were drawn, followed immediately by the baseline dynamic Tc-99m DTPA renography. Venous blood without anticoagulants was used for aldosterone determinations, whereas for renin determinations, pre- chilled vacutainers were used. Four hours later, patients were given 25-50 mg of captopril. Exactly one hour after captopril administration, blood samples were taken again, and second DTPA renography was started. Out of 223 patients processed, eighteen had elevated values of PRA and aldosterone in captopril test. Aldosterone and plasma renin activities were determined by commercially available radioimmunoassay kits.Conclusions: Determinations of plasma renin and aldosterone in captopril tet is a simple and non-invasive method. Therefore, it has an increasing appliance, both as a useful diagnostic screening test for renovascular hypertension, as well as in evaluation of success of invasive procedures performed in patients with confirmed renovascular hypertension.

TP43 Clinical usefullness of NeutroSpec®, a new Tc-99m labeled antibody based WBC imaging for various types of infections in two different hospital settings. Y. Takamiya1, M. Farooqui1, N. Rosner1, R. Mendi2, M. J. Blend2, S. Hanhan2; 1St. James Hospital & Health Center, Chicago Heights, IL, United States, 2University of Illinois Hospital, Chicago, IL, United States. Aims: NeutroSpec® (FANOLESOMAB) is a new FDA approved Tc-99m labeled antibody based WBC imaging procedure approved for equivocal signs and symptoms of appendicitis in patients who are five years of age or older. We investigated the clinical usefulness of NeutroSpec® Imaging in a variety of infections in two different hospital settings.Materials and Methods: 39 patients (pts) [25 females, 14 males] with an age range of 24 to 103 years [mean = 61.1] were studied between November 2004 and December 2005. 28 pts were imaged at St James Hospital & Health Center and 11 pts were imaged at University of Illinois Hospital. NeutroSpec® examinations were performed on a SEIMENS E-Cam Duet and a Phillips Prism 2000 dual headed Camera, following the administration of 555 to 740 MBq of Tc-99m-labeled antibody according to the manufacture’s suggested protocol. All images were successfully completed within 4 hours without any observed side effects. Individual NeutroSpec® findings were

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3. 4.

compared with other imaging findings and the final discharge diagnosis as a measure of clinical usefulness. The indications for the studies included fever of unknown origin (FUO), limb cellulitis and osteomyelitis, urinary tract infection, Crohn’s Disease, non-specific leukocytosis, pneumonia, ulcer and wound infections. Findings: NeutroSpec® altered pt management and was found to be clinicaly useful in 20 of 39 cases (51%). NeutroSpec® was used to clarify equivocal bone scan findings in 16 cases with suspected cellulitis vs osteomyelitis. There were 12 true positive (75%), two true negative (12.5%) and one false negative finding (6%). This would suggest an accuracy rate of 93.7% in this small sample. 10 pts were imaged for FUO or nonspecific leucocytosis and none demonstrated positive findings or altered pt management. 6 pts were imaged for pneumonia or suspected line sepsis and none were helpful. 3 pts were imaged for the presence of active Crohn’s Disease of which 2 cases were thought to be false negatives. Conclusions: NeutroSpec® imaging was found to be clinically useful when used in combination with the nuclear bone scan to distinguish between cellulitis and osteomyelitis. Insufficient data is available to comment on the usefulness of NeutroSpec® in other types of infection.

TP44 Predictive value of lung alveolar clearance in the follow-up of systemic sclerosis: correlation with lung functional parameters and radiological findings N. Prandini1, V. Cestelli2, S. Panareo1, R. La Corte2, S. Fabbri3, M. Casali1, M. Giganti1, C. Cittanti1, A. Costanzo1, F. Trotta2, L. Feggi1; 1Nuclear Medicine, Ferrara, Italy, 2Rheumatology, Ferrara, Italy, 3Health Physics, Ferrara, Italy. Aim: Lung involvement rapresents the more frequent localization of Systemic sclerosis (SSc). Alveolar clearance (AC) of 99mTc-DTPA is an important prognostic value of the increased permeability of the alveolus-capillary membrane. The aim of this study was to establish if AC will be predictive of stability or progression of sclerodermal lung involvement in a group of patients affected by SSc. The research has been carried out through the correlation between functional respiratory parameters (FRP) and lung High Resolution Computed Tomography (HRCT).Materials and Methods: We studied 75 consecutive patients no smokers [70 females and 5 males, mean age 53 yh (range 23-73)], affected by SSc: 49 with a limited disease and 26 with systemic cutaneous involvement. The mean follow-up was of 30 months (range 6-60). All patients were studied with 99mTc-DTPA, for the evaluation of AC (n.v. > 55 min.), FRP (FVC and DLCO) and lung HRCT (Warrick score).Results: At first evaluation (time 1), on the basis of AC, all patients were divided in accelerated clearance [A] (43 cases) and normal [N] (32 cases). The AC data were subsequently correlated with functional parameters and HRCT. We have founded a meaningful statistically difference in 2 groups only concerning CO2 diffusion (p < 0.0001) and HRCT total score (p < 0.0074). The positivity of ACA and anti-Scl70 antibody shows a meaningful statistically distribution between the 2 groups of patients (p =0 .008). At second evaluation (time 2), we divided the 2 groups of patients (N and A) in 4 subgroups on the basis of the maintenance or changing of the same parameter [A - + A (50%); A - + N (8%); N - + N (33%); N - + A (9%)]. The lung involvement was evaluated in all patients: we considered meaningful only variations > than 15%. The same evaluation was applied for patients with disease not superior to 5 years at first observation. Ten patients of 21 with A, showed an aggravation (48%), while 5/21 showed an improvement (24%). The improvement was not confirmed in the other subgroups.Conclusions: The AC data can be used like a precocious marker of lung interstitial disease, although it does not show a predictive value in the follow-up of patients with SSc.An accelerated clearance cannot be considered as prognostic marker of worsening of lung involvement, furthermore a normal one is not expression of FRP stability.

TP45 Optimization of staff radiation protection during therapy

90

Y Zevalin

N. Guilabert1, S. Prevot2, M. Laporte1, C. Touzery2, J. Coulot1, F. Lavielle1, M. Ricard1, J. Lumbroso1, A. Berriolo2, J. Riedinger2, F. Brunotte2, M. 1 Institut Gustave Roussy, Villejuif, France, 2Centre Schlumberger1; Georges-François Leclerc, Dijon, France. Introduction : Zevalin® is approved for the treatment of B-cell follicular non-Hodgkin’s lymphoma. The antibody is labeled with 90Y (Ytracis®, beta-emitter, Eȕmax 2284 keV). Duration of injection should be at least 10 min. Depending on the bone marrow involvement, the activity administered ranges from 11 to 15 MBq.kg-1. The maximum administered activity must not exceed 1200 MBq. Although 10 mm of Lucite is usually considered suitable to absorb any beta radiation, high activities and high energy ȕ rays of 90Y produce a large amount of bremsstrahlung. To optimize the radiation protection of workers, the exposure when using various protection devices has been evaluated. Materials & Methods : Considering the labeling step, two types of syringe shielding and one dedicated vial shielding (Medisystem) were used. Regarding the administration procedure, a double channel syringe pump (PROGRAM 2, Fresenius Vial) was used. This device allows intravenous infusion at low flow rate followed by NaCl 0.9% infusion. Finally, the efficiency of an additional freezing bag in contact with the PVC extension line was evaluated. To perform dose measurements, we used NaI doserate-meter (FieldSpec - Target) and thermoluminescent dosimeter chips (GR-200A) and TLD rings. Results : Syringe shielding decreased the dose rate by a factor of 3 to 10, depending on the syringe volume (1, 2.5, 10 mL) and shielding material (Tungsten or Lucite). The best protection was obtained with the 5 mm tungsten shielding. For the vial, the highest protection was obtained with 6 mm of Lucite surrounded by 20 mm lead glass that divided exposure by 8. Considering the dose rate with a 10 mL syringe and the best shielding (5.10-3 mSv.h1.MBq-1) and 15 minutes of manual injection, the total dose delivered to extremities would be 1.3 mSv. In contrast, using an electric infusion pump, the exposure measured was 0.24 to 0.74 mSv (depending on the region of the hand), being divided by 2 to 6. Regarding the efficiency of the freezing bag, a ratio of 2 was found between the exposure at two centimeters in the air from the vial and at its contact. Conclusion : We identified the most convenient radiation shielding to optimize staff exposure during Zevalin therapy. We recommend also to develop an automatic procedure for administration with a double channel syringe pump. This work shows that all phases of treatment procedure can be optimized, and particularly the administration to the patient.

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TP46 Quality assurance in nuclear medicine: a professional and practical approach M. de Groot, A. P. W. Meeuwis, E. P. Visser, J. A. van Dalen, F. H. M. Corstens; Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. Aim Quality control (QC) is an important issue in determination of the integrity of nuclear medicine equipment. High standards are demanded for such equipment, especially in relation to image quality, quantitative imaging, therapy, dosimetry and size- or volume-measurements. Maintenance contracts of the manufacturers are insufficient to guarantee these high standards. Nowadays, in the Netherlands there is no strictly defined legislation for quality assurance (QA) of nuclear medicine equipment, but it has close relations with other types of legislation, as radiation protection. Furthermore, in 2000 the Dutch society of nuclear medicine published recommendations on how quality testing and assurance should be performed. However, these guidelines contain many tests which take up considerable time, leaves little space for personal adaptation and in some points are out-dated. Therefore, our aim was to define and set up a practical and transparent QA-system of all equipment installed in our department, i.e. 5 gamma cameras, 2 PET(-CT) systems, a whole-body counter, a bone-densitometer and multiple dose calibrators and gamma counters. Methods A QA-group was formed 2 years ago, consisting of two medical physicists, a chief-technologist and a senior technologist. Firstly, decisions were made to define the outlines of the QA-system. This started with an inventory of major nuclear medicine equipment and a review of all existing QC-protocols. Based on the recommendations, specific tests were selected, giving optimal information on system quality. Furthermore, adaptive frequencies for most tests were introduced, excluding daily quality checks. QC-protocols were reviewed on accuracy and updated to meet manufacturer specified requirements. Operational action levels were added to stay within these requirements. Results of quality testing are processed, centrally archived and reviewed using MS EXCEL, allowing direct accessible data with graphical evaluation. Overall quality of equipment and issues are evaluated and discussed in the QA-group on a regular basis. Results After two years, full QA can be given to all equipment. Using the protocols, QC-tests are easy to perform without taking too much time. Central archiving makes it easy to recognise trends in test parameters and with the action levels it is therefore clear when test results are out of specifications. Conclusions A professional and practical QC/QA-system was introduced in our department. A dedicated QA-group, up-to-date QC-protocols, adaptive test frequencies and central archiving of results form the basis of a transparent and effective system. We consider our QA/QC-system as an absolute necessity to guarantee the high standards of nuclear medicine equipment today.

TP47 The role of the Nuclear Medecine technician in reducing artifacts of PET/CT images. F. Hernoux, M. Soimeo, P. Just; Hospital Saint-Louis, Paris Cedex 10, France. AIM: Define the new skills necessary for a technician to improve image quality.Materials and Methods: Since the installation of PET/CT in our hospital (06/25/2004), we tried to determinate with medical team the various problems related to patient preparation in order to obtain high quality images. So, we studied the impact of different solutions to reduce artifacts related to patient preparation.Results: Five mains problems and their solutions were identified: - Brown fat accumulation of the tracer can be reduced by warming-up the patient using a blanket before and after the injection and during the exploration. - Non-specific muscular uptake could be diminished by creating a quiet environment and, if necessary, the use of Benzodiazepine drugs. A bladder catheterization could be used in some patients for the evaluation of genito-urinary organs. - Gastrointestinal opacification by oral contrast agent could be used in some patients to differentiate physiological from pathological gastrointestinal uptake of 18F-FDG. - In case of hyperglycaemia, subcutaneous injection of rapid insulin was used to improve tumoral accumulation of the tracer. We did keep in mind that this insulin injection could generate some artifacts by increasing intra-muscular uptake, if the lag between insulin injection and 18F-FDG injection was too short (less than two hours). The appropiate proposals for such problems allow easier interpretation of the images.Conclusions: The above-mentioned methods that we set up progressively in our department are landmarks to pursue a continuous improvement of image quality.

TP48 Display of Image Inhomogeneity by stepwise Truncation M. Schlotter, T. D. Reuter, M. Schulz; Allgemeines Krankenhaus Hagen, Hagen, Germany. Aim Uniformity is defined as the quotient of the maximum minus minimum counts divided by the sum of maximum and minimum counts irrespective of where the respective pixels are found. Since a submaximal inhomogeneity in the image center may have a greater impact on SPECT results than a maximal one at the margin it seems to be worth developing an algorithm that can display submaximal inhomogeneities. Methods To visualize non-uniformity we divided the part of the z-axis between the minimum and maximum pixel content of a 128/128 matrix into16 equal steps of truncation. Furthermore, we transformed each layer that represented a step of truncation into a binary mask. The binary counts of each layer were determined and divided by the number of the total pixels. By this we could determine the percentage of all of the layers defined by truncation. The procedure was executed by a PIXIE macro program. Three scans with a maximum inhomogeneity of 2.2%, 5.3% and 6.1% were evaluated by an experienced technologist and a newcomer. Results and conclusions The program provides reproducible results irrespectively of the grade of expierence and image inmhogeneity and might even allow for a Ȥ2-test.

period, no untoward side effects were observed in any of our patients, even those with cholelithiasis.

TP49 Dicom modality worklist for PET system Siemens Ecat Accel

Aim of this work is interconnection of non-DICOM modality PET system Siemens Ecat Accel with DICOM modality worklist server AMIS*PACS in practice. Material: PET system Ecat Accel (Siemens, Germany), DICOM modality worklist server AMIS*PACS (RASNA Imaging Systems, Italy), software DCMTK 3.5.4 (The OFFIS computer science institute, Germany), software (X)medcon (open-source, http://xmedcon.sourceforge.net).Methods: One of the most important attributes of every hospital information system (HIS) is truly assort required image informations for given patient. Interconnection of HIS, PACS and on the side of source imaging modality (in our case PET) in the form of DICOM modality worklist is the very well proofed method how to guarantee it. Although acquisition console ECAT of PET system Siemens applies the same hardware (Sparc CPU) and software (Unix operating system Sun Solaris) platform as other vendors e.g. GE, has not any software equipment for DICOM transfer and as well for conversion of its native image format (in our case ecat7) to format DICOM 3.0. Purchase of evaluating workstation ESOFT Siemens with requested DICOM implementation could appear as the best solution on commercial basis. Unsuitability of this design turns up in case of necessity to use some generally long-established characters (in our case slash) in unique patient ID e.g. 123456/7890. ESOFT DICOM modality worklist scheduler uses along export of patient database records to acquisition console ECAT entitling in the form of {$surname}.{$patient_id}.db which results in error because used operation systems (Solaris on ECAT and Windows on ESOFT) disallow slash as character in file name. On the basis of the above mentioned was designed and realised DICOM modality worklist in the form of intranet application running on hospital intranet server and launched in Internet explorer of acquisition console ECAT.Results: Realized solution allows medical staff very simply insert true patient data in acquisition protocol on scheduled imaging modality. Obtained image data in native format ecat7 are then after DICOM 3.0 conversion transferred to PACS.Conclusions: Benefit of presented solution is smooth and very clean implementation even on relatively very closed systems, realization using free software tools and last but not least is the cheapest.

TP50

TP52 Atmosphaere music on patients during gamma camera acquisition for myocardial perfusion scintigraphy. M. Gerhardt; Denmark.

Herlev Hospital, University of Copenhagen, Herlev,

AIM: To evaluate the effect of specially composed atmosphaere music on heart rate and patient well-being during image acquisition in rest and stress myocardial perfusion imaging.Methods: 50 patients referred for myocardial perfusion imaging on the suspicion of ischemic heart disease were included in a randomised cross over study. 24 women and 26 men were included. Patients with reduced hearing, arrhythmia and/or pacemaker, dementia or dyslexia were not included in the study. Only studies with successful gating at both rest and stress image acquisition were included. 28 patients listened to music during acquisition of rest images and without music during stress image and 22 patients vice versa. Heart rate was registered before and after image acquisition. After each image acquisition the patients filled in a questionnaire on the effect of music/no music. They were asked whether they liked the music as such and if they would prefer to select the kind of music played. The patients were asked if the effect of the music played was calming, distressing or had no effect. They were also asked if they appreciated/did not appreciate music during the acquisition or if they were indifferent. The music played is named MusiCure. It is not related to any specific genre and composed with the purpose of creating a relaxed atmosphere. The music is non vocal, slow in tempo and performed with acoustic and electric instruments and nature sounds.Results: 85% of the patients preferred to listen to music during image acquisition, and 52% would prefer to select music of their own choice. 79% of the patients declared that the music had a calming effect, 17% no effect, and 4% found it to be distressing. There was no significant change in heart rate during acquisition after rest regardless of music being played or not. Mean heart rate decreased 3 beats per minute during stress regardless of music being played or not (p<0.01).Conclusions: A vast majority of patients preferred to listen to music during image acquisition for myocardial perfusion imaging, but half of the patients preferred to select the music themselves. The music did not contribute to changes in heart rate. Music can be played during image acquisition with a calming effect on most patients without affecting heart rate.

Teaching research using a writing intensive paradigm

TP53

G. D. Heggie; States.

An effective protocol used in the administration of oral contrast given to patients prior to a PET/CT scan

University of Missouri-Columbia, Columbia, MO, United

In the recently released U.S. News and World Report’s Best College for You: 2006 Edition, the University of Missouri (MU) was recognized for “Writing in the Disciplines -- the fourth consecutive year MU has received this accolade. Similarly, the Conference on College Composition and Communication (CCCC - the oldest professional organization devoted to college teaching) honored MU awarding it the 2004 Writing Program Certificate of Excellence -the first year that this award has been offered. Undergraduate programs at MU require students to successfully complete a number of courses designated as meeting the university’s criteria for being “Writing Intensive” (WI). MU’s Campus Writing Program (CWP) oversees the design, delivery and quality of WI courses and ensures that each one meets or exceeds a stringent set of requirements set by its board. As summarized on the CWP web page - Writing Intensive courses help produce an educated, articulate citizenry capable of reasoning critically, solving complex problems, and communicating with clear and effective language. MU's writing requirement -English 1000, followed by two WI courses -- is part of a 30-year-old trend in U.S. higher education known as "writing across the curriculum," or "writing in the disciplines." Since 1987, every undergraduate degree granted by MU has been strengthened by the WI requirement. Increasingly over that last decade or so, professional bodies representing many of the health disciplines, accreditation agencies and employers have recognized the need for new health professions graduates to possess critical thinking skills, to be able to interpret and participate in basic research, and to have the skills needed to communicate effectively in both verbal and written forms. For a number of years students in the Radiography, Nuclear Medicine Technology and Respiratory Therapy programs at MU’s Columbia campus have been taking a WI-based Introduction to Research course which addresses the issues discussed above. Experiences with this well-received offering have been broadly used within the university as well as on a number of other campuses as part of an ongoing effort to share with others ideas, insights and techniques that have proven to be useful and effective. The focus of this presentation will be to use the research course as a model to describe, discuss and demonstrate many of the key features and techniques of this approach to teaching, and to show how much of the curriculum that health professions educators are expected to present can use the WI paradigm.

TP51 Is the lack of small bowel visualization during hepatobiliary imaging, a contraindication for CCK-8 administration? A. J. Arroyo1, H. B. Semaan2, R. N. Desai2, Y. P. Patel3; 1St. Vincent Mercy Medical Center, Toledo, OH, United States, 2The Medical University of Ohio (MUO), Toledo, OH, United States, 3St Vincent Mercy Medical Center, Toledo, OH, United States. Objective: The usefullness of CCK-8 in the evaluation of gallbladder disease, the most common digestive sytem illness, is well established as a diagnostic tool. A common bile duct occlusion may be considered if there is a persistent nonvisualization of the small bowel, which may preclude its administration. The purpose of this study is to determine if such an imaging patern is a contraindication.Methods: CCK-8 studies of the last 3 years were reviewed. Each study was performed after a 4-8 hr fast and with 3 mCi (111 MBq) of Tc-99m Mebrofenin. Data collection was for 2 hrs. A dual head camera set in the Rt.Lat and LAO projections with a 128x128x16 was used at a rate of 1 min/frm. 0.02 ugrm/Kg of CCK-8 in a 20 ml normal saline IV bag was given over 30 minutes at 1 hr into the study.Results: CCK-8 was infused in 87 patients at 1 hr. Their GBs were fully visualized. But no trace of small bowel activity was seen. However none of the patients had any adverse reactions during the administration or immediately after.Conclusions: Provided the CCK-8 dosage is further diluted in a 20 ml IV bag and infused over a 30 minute

S. Mundon-Hooper, L. M. Wilson, J. M. O'Sullivan, S. E. McEvoy, J. A. Lucey, A. MacArtain, C. Constable; Blackrock Clinic, Dublin, Ireland. Aim: The objective of this study was to establish an effective protocol for the administration of oral contrast in dual-modality Positron Emission Tomography, without compromising patient care and 18FDG uptake.Materials and Methods: Over a period of 8 months, 100 patients were examined using 3 different oral contrast protocols. All patients were scanned 1 hour post FDG injection. The 1st protocol (n = 20 patients) uses 12 ml of Gastrografin diluted in 1000 ml of water. 800 ml of contrast was given to the patient 1 hour prior to FDG injection and a further 150 ml just prior to examination. The 2nd protocol (n = 50 patients) uses 20 ml of Gastrografin diluted in 1000 ml of water. 300 ml of contrast was given to the patient prior to FDG injection, a further 450 ml was given 30 minutes after FDG injection and finally 150 ml was administered just prior to examination. The 3rd protocol (n = 30 patients) uses 20 ml of Gastrografin diluted in 1000 ml of water. Thirty minutes prior to the FDG injection 150 ml of contrast was given to the patient, a further 150 ml was then given just before the FDG injection. Thirty minutes later an additional 450 ml was given to the patient and finally 150 ml just prior to the examination. In protocols 2 and 3 the PET images were assessed for any additional muscle uptake due to the fact that patients were drinking during the FDG uptake period.Results: The 1st protocol showed contrast in the large bowel but lacked contrast in the small bowel. The 2nd protocol showed contrast in the small bowel but lacked contrast consistently in the large bowel. The 3rd protocol showed optimal contrast in both the small and large bowel In the 2nd and 3rd protocols the PET images showed no additional muscle uptake.Conclusions: We found the 3rd protocol most effective as this showed optimal contrast in the small and large bowel and importantly drinking contrast during the FDG uptake period does not compromise PET images.

TP54 Medical Ethics in Telenuclear Medicine M. Oliveira1, M. Martins2, L. Cunha3, M. Pereira2, R. Castro1, A. Inês1; 1 Hospital Geral de Santo Antonio, Porto, Portugal, 2Hospitais da Universidade de Coimbra, Coimbra, Portugal, 3Escola Superior de Tecnologia da Saúde do Porto - IPP, Porto, Portugal. Introduction: The development of electronic patient databases and medical records allow the access to a great number of health care workers located at distant and/or different geographic sites is an important feature of telemedicine. However, questions related to privacy, confidentiality, security and integrity of information arise and cannot be discarded, given the actual widespread of telemedicine. The aims of this report are to determine methods of integrity and quality preservation of medical information related to acquired data in the nuclear medicine department, to the privacy of patient, to confidentiality in the department system and to responsibility about the patient and its data.Materials and Methods: Telenuclear medicine refers to the interpretation or consultation of nuclear medicine data at a distant location from the one where data were acquired. Telenuclear medicine equipment is used to implement telemedicine in the department and the same equipment can be used for both telenuclear medicine and on-site medicine. The implementation of a strategic plan to assure quality and integrity in what concerns patient data requires the establishment of a conduct policy concerning the usage of the telenuclear medicine system of the department. Therefore, the communication protocol in (or from) the department must allow the confirmation of reliable transmission; encrypted transmission of data improves the security of transmission over public channels; the remote monitor should have the same quality control as on-site monitors. Results and Conclusions: The

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Poster Presentation

J. Bartl1, V. Sochorova2; 1Department of Nuclear Medicine, Masaryk Memorial Cancer Institute, Brno, Czech Republic, 2Department of Hospital Pharmacy, Masaryk Memorial Cancer Institute, Brno, Czech Republic.

fundamental pillar of an ethical code philosophy is the one of obligation to consider that which individual has dignity and moral values of its own. This way, to proportion on-line medical health care, transporting the knowledge and, in this case, medical images instead people or paper supports requires the establishment of a rigorous ethical code which preserves, above all, the patient. In order to maximize its advantages, telenuclear medicine must be lifted over a solid base of respect by the neighbour.

TP55 Issues from Reporting Nuclear Radiographers and Technologists

Medicine

studies

by

K. G. Holmes1, P. Hogg2; 1St Martins College, Lancaster, United Kingdom, 2 University of Salford, Salford, United Kingdom. Aim For many years radiographers and technicians have been undertaking duties outside their traditional role. These professional groups have extended their role to include new responsibilities that were previously considered to be in the exclusive domain of other health care professionals. This paper will aim to discuss issues which have arisen from this process. Methods To date over 50 students have successfully completed one of the two programmes of study for Radiographers and Technologists wanting to undertake reporting of studies in nuclear medicine. Previous conference papers have discussed the growing body of evidence that Radiographers and Technologists can report nuclear medicine studies with a degree of accuracy similar to medical practitioners. Analysis of “Course work” including the portfolio was undertaken and the results analysed. The presentation will be grounded in published literature, evidence from the programmes of study and the experience gained form promoting and presenting the evidence. The presentation will explore the physical, perceptual and cognitive aspects of the reporting process, the environment for reporting, how to view images and factors which may cause errors in the process. It evaluates the audit process, what to do when errors are made and a possible protocol for standard setting in Nuclear Medicine reporting. ConclusionsThere are a number of issues arising from the research into radiographers reporting. Evidence shows there is a high level of concordance between radiographers / technologists and their radiological mentors. There is enhanced patient management and radiographers / technologists undertaking the role have greater job satisfaction and well-being.

TP56 Using “Case studies” to reflect upon the role of the Reporting Radiographer in Nuclear Medicine. K. Holmes1, M. E. Welsh2, K. Wakefield3; 1St Martins College, Lancaster, United Kingdom, 2Morecambe Bay Hospitals Trust, Lancaster, United Kingdom, 3Penine Acute Hospitals Trust NHS Trust, North Manchester General Hospital, Manchester, United Kingdom. Aim Reflection on clinical practice is now an integral part of the educational process used in a number of course in nuclear medicine. This process can be used to look back at a ‘critical incident’ or event which upon evaluation enables the radiographer to give an impetus to change practice. This paper will discuss this process and evaluate a “Case study” approach. Method This paper will discuss reflective practice in nuclear medicine reporting and use 2 “Case studies” to illustrate its application. Both give examples of how a radiographers working in the profession can use reflection to look at elements of our practice which may be changed to enhance the management of our patients. Results The 2 examples discussed in this paper have outcomes which may generate ideas for other radiographer practitioners to reflect upon their own protocols and practice. This may lead to a change in the management of the patient and an improvement in patient care. Both of these actions keep in line with modern day ethos that radiographers are expected to undertake a certain amount of continued professional development in order to “ maintain and strive to improve their professional knowledge and competence”1. Conclusions Reflective practice may generate a greater understanding into the reporting process and lead to an improvement in the overall patient management. It should result in a reduction in the total number of visits to the Radiology department and hopefully create a more holistic process. 1 Statement for Professional Conduct (2002) College of Radiographers, London

TP57 Double-Phase Parathyroid Scintigraphy in the Identification of Hyperplasic Condition - Application of two different methodologies of image processing M. Oliveira1, A. Mendonça2, A. Bastos3, C. Rosa1, A. Inês1; 1Hospital Geral de Santo Antonio, Porto, Portugal, 2Faculdade de Engenharia do Porto, Porto, Portugal, 3Instituto Português de Oncologia do Porto, Porto, Portugal. Introduction and Objectives: Approximately 85% of primary hyperparathyroidism cases are due to a parathyroid adenoma. The remaining cases are caused by a condition called hyperplasia or by a cancer of the parathyroid gland (~1%). The treatment for these conditions is essentially surgical. Operative failure is particularly associated with the ectopic location of the hyperfunctioning gland, multiple gland involvement, supernumerary glands, small size of the tumour, or failure of recognition by the surgeon, that result in incomplete resection of parathyroid disease tissue. A non-invasive imaging technique that could accurately identify both adenomas and hyperplasia will aid the surgeon, reducing operating time and the frequency of reoperation also as the decrease of operative complication and surgical morbidity. The doublephase Parathyroid Scintigraphy with 99mTc-MIBI is a height sensitivity (70 - 90%) study in the identification of adenomas but falls in hyperplasic condition (60%) due to low signal to noise and small gland size. The aim of this study is to confirm the accuracy of double-phase method in the identification and localization of hyperplasic glands, after the application of two different methodologies of image processing (conventional and the new algorithm developed).Materials and Methods: The acquisition was performed on a dual-head camera (Siemens e.cam signature), using low-energy and high resolution collimators. A 20% energy window centered on 140keV was used for data acquisition. Planar images were performed with the patient in supine position with the neck in hyperextension. Images were acquired as 256256 matrices, zoom 3.20, for 600

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seconds, 10 minutes and 3 hours after the administration of 99mTc-MIBI. The same conditions were utilised for the 99mTc-pertechnetate image, acquired after the last one. The images obtained were lately submitted to different processing methodologies: conventional (display of the images, manipulation of bright and contrast) and the new algorithm (based on geometric registration, noise estimation and removal with change detection).Results: The analysis of the results obtained and the findings evidenced in this report allow a comparative evaluation concerning to the applied imaging processing methodologies. All the values obtained will be validated whit statistical applicable analysis methods. Table of ContentsConclusions: The 99mTc-MIBI doublephase technique is an effective, non invasive and easy to apply technique, that requires only one administration of a radiopharmaceutical instead of the two required for the subtraction method, so the cost and radioactive burden involved in this methodology is reduced. Also requires less operator expertise and costly equipment than the subtraction technique.