P511

P514

Plasmapheresis to allow Radioiodine treatment of a high-risk differentiated thyroid carcinoma with a history of 3-year amiodarone treatment.

The effect of a single dose of rhTSH on I thyroid uptake, scintigram pattern, serum concentrations of selected 131 apoptopic markers and on the outcome of I therapy in patients with non toxic nodular goiter.

Therapeutic management of amiodarone induced dysthyroidism has been extensively described and plasmapheresis has already been used in severe amiodarone-induced thyrotoxicosis. Since amiodarone is very rich in iodine, persistent iodine excess can prevent radioiodine (RI) treatment. We present a case of a 55-year-old man, with a history of atrial fibrillation, who has been maintained on amiodarone treatment (200mg/day) during 3 years. The patient underwent total thyroidectomy for a thyroid nodule and a papillary thyroid cancer with extra-thyroidal extension and central lymph nodes metastases was diagnosed. Therefore, RI treatment was indicated. Although amiodarone was discontinued for 2 years, iodine overload (based on high urinary iodine excretion: 472 µg/24h, normal range <150µg/24h) was found. At that time, in order to monitor spontaneous iodine elimination, the patient began L-T4 treatment, but 3 months later, similar iodine excess persisted. Therefore, as spontaneous elimination of iodine overload could not be expected in a reasonable time, plasma exchange (PE) was undertaken and LT4 treatment was stopped and replaced by LT3. After 2 PE, at day 5, serum iodine concentration fell from 811 nmol/L (before) to 469 nmol/L. At that time, LT3 was stopped, and 6 additional PE were performed to reach serum iodine of 71 nmol/L on day 30. Finally, a total of eight PE were needed over a four-week period. Simultaneously, iodine urinary excretion significantly decreased from 230 (before) to less than 84 nmol/mmol creatinin (after 8 PE) which thus allowed the administration of RI treatment (4 GBq 131I) on day 30. Post-therapy whole body scan, performed 5 days later, revealed cervical uptake (0.48% of the total administrated dose) corresponding to usual thyroid remnants. L-T4 treatment was then reintroduced to reach a suppressive dose. The efficiency of the ablation was confirmed 6 months later by normal cervical ultrasonography combined to an undetectable level of serum thyroglobulin (< 0.6µg/L) after rhTSH stimulation. In conclusion, plasma exchange is a reliable and effective method for iodine excess elimination. It can be useful when spontaneous elimination of iodine is very slow in order to allow RI treatment.

P512 Rosiglitazone effect on I-131 uptake in thyroid carcinoma patients with negative TBS and high Tg: A preliminary report with correlation to PPAR-gamma expression S. Tepmongkol, S. Keelawat, S. Honsawek, P. Ruangvejvorachai; Chulalongkorn University, Bangkok, Thailand. Surgery together with radioiodine (RAI) therapy is a main treatment in well-differentiated thyroid carcinoma. However, in some instances, these tumors can be converted to the form that does not accumulate RAI and unable to be treated with RAI. The aim of this prospective clinical trial was to evaluate the effect of rosiglitazone (RZ) on RAI uptake by thyroid carcinoma those previously had post-RAI treatment total body scan (TBS) negative and high thyroglobulin (Tg). Seven patients with previous post-RAI treatment TBS negative and high Tg were enrolled. Four had negative and 3 had positive PPAR-Ȗ expression. Eight milligrams daily of RZ was given to all patients for 6 weeks before diagnostic TBS. High dose of I-131 (5550 MBq) was given to all patients after RZ. After RAI treatment, 2 of 3 patients with PPAR-Ȗ positive had high I131uptake, while none with negative PPAR-Ȗ had uptake. Thus, RZ may have a positive effect on restoration of I-131 uptake in previously negative TBS and high Tg thyroid carcinoma patients.

P513 Radioiodine treatment effects on lacrimal gland function in patients with thyroid cancer A. Fard Esfahani, H. Mirshekarpour, B. Fallahi, M. Eftekhari, M. Saghari, D. Beiki, A. Takavar; Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of). Aims: The few case reports confirming the radio-iodine presence in the tear as well as few reported cases of lacrimal gland dysfunction after radioiodine therapy raised the need to clarify whether lacrimal gland function can be affected by radioiodine therapy. Hence we planned a historical cohort study to evaluate this effect.Materials and Methods: We studied 100 eyes of 50 patients who had received high doses of I-131 (cumulative dose: 100-450mCi) for treatment of differentiated thyroid carcinoma (exposed group). The patients were studied at least 3 months after their last radioiodine therapy. Dry eye symptoms (obtained via a standard questionnaire) and Schirmer I test results (mm/5min) of this group were compared with unexposed group (100 eyes of 50 individuals) sex and age matched. Cases with another known cause(s) of dry eye were not included in either group.Results: The study demonstrated a significantly lower wetting amount of the Schirmer paper in exposed group compared to unexposed group. The mean of Schirmer test in the exposed group was 14.5± 10.8, while this value was 18.2±11.0 for the unexposed group (p=0.016). In the exposed group, wetting results were 0-4 mm in 21%, 5-9 mm in 20% and • 10 mm in 59%, while these results were as 6%, 17% and 77% in the unexposed group, respectively (p=0.004). In a qualitative form of analysis by chi-square method, by considering strip wetting • 10mm as normal and less than that as abnormal, 41% of the exposed eyes versus 23% of the unexposed eyes had abnormal test (p=0.006). In subjective evaluation 51% of the exposed eyes and 50% of the unexposed ones revealed at least one of the dry eye symptoms in the questionnaire. Data analysis showed no significant difference between the number of symptoms of two groups, but 2 symptoms (burning sensation and erythema) were significantly higher in the exposed eyes. Among the 10 eyes with burning symptom only one patient (2 eyes) revealed abnormal Schirmer test result.Conclusions: Reduction in the tear secretion from major and/or minor lacrimal glands is seen after high-dose radio-iodine therapy, which seems to be severe in many cases; however dry eye symptoms are no more than unexposed population. Key words: complication, Iodine-131, lacrimal glands, radioiodine therapy, thyroid cancer

A. ParfieĔczyk, F. Rogowski, B. Kiersnowska-Rogowska, S. Abdelrazek, A. Sopotyk, P. Szumowski, A. Kociura-Sawicka; Medical University of Bialystok, Bialystok, Poland. Aim: The purpose of the study was to investigate whether rhTSH pretreatment induces changes in thyroid uptake and regional distribution of radioiodine on scintigrams in patients with nonmalignant, non-toxic goiter, and what influence have a use of single dose of recombinant TSH on concentration of selected apoptopic markers in serum after 131I therapy. Materials and methods: The study was performed on 30 patients (female and male aged 45-78) with euthyroid goiter referred to our Department for goiter reduction. A reference groups were: a) ten healthy volunteers for apoptotic markers, b) study patients before rhTSH injection. Serum concentrations of TNF-Į, sFasL, p53 and Bcl-2 were determined using ELISA kits. All patients were pretreated with a single dose of 0.05 mg of rhTSH. Radioiodine uptake (RAIU) and thyroid scan were studied three times: before, 24 and 48 hours after use of diagnostic dose. The therapeutic activity of 131I was calculated using Marinelli’s formula and administered 72 hours after rhTSH injection. The absorbed dose was between 200 and 280 Gy. The concentrations of TNF-Į , sFasL and Bcl-2 and thyroid hormones (fT3, fT4 and TSH) were assessed: pre-therapy, two weeks, 1, 2, 3, 4 and 5 months post therapy. The local ethics commitee for human studies approved the study.Results: RAIU increased 2 to 8 fold after rhTSH. The distribution of radioiodine was considerably more homogeneous 48 hours after injection of rhTSH than in the baseline scintigram. During the two weeks after therapy, the mean concentration of TNF-Į rose by 60%, systematically decreasing during next months. The mean concentrations of sFasL remained low before and after therapy. The p53 concentration was the highest before 131I and the lowest after 5th month of observation. Bcl-2 concentrations in the sera of patients showed a slight increase after therapy, but remained low by the end of our observations. After five months observation the mean reduction in goiter volume was 19%. Thyroid function tests in all treated patients showed decreases in serum fT3, fT4 and rises in TSH concentrations, keeping within the normal range.Conclusions: Pretreatment with a single dose of rhTSH enables 131I-therapy in the patients with low RAIU. The administered dose of rhTSH significantly decreases the therapeutic activity of 131I. The relatively low reduction in thyroid volume probably results from the antiapoptotic action of rhTSH. The changes in concentrations of studied apoptotic markers we observed seems to confirm the above conclusion.

P515 Prognostic indicators in patients with differentiated thyroid cancer receiving repeated I-131 therapies G. Storto1, R. Liuzzi1, M. Klain1, C. Albanese2, B. Salvatore2, T. Pellegrino2, L. Cella1, A. Soricelli3, L. Pace2, M. Salvatore2; 1Institute of Biostructures and Bioimages, CNR; University “Federico II”, Naples, Italy, 2Department of Biomorphological and Functional Sciences, University “Federico II”, Naples, Italy, 3Diagnostic Imaging, Parthenope University, Naples, Italy. Aim: Processes underlying the different responsiveness of differentiated thyroid cancer (DTC) to iodine-131 (I-131) treatment are still debated. We retrospectively evaluated the capability of multiple clinical and instrumental parameters in predicting disease response in patients (Pts) with DTC who received two radioiodine treatments. Material and Methods: 76 Pts (56 W; mean age 58±17 years), with histologically proven DTC (47 papillary; 24 follicular; 5 others) underwent post-surgery I-131 therapy (4144 ± 1369 MBq) and within about 15 months were retreated because of evidence of disease relapse. Undetectable serum thyroglobulin (Tg) values 8 months after the second I-131 administration (4995 ± 1998 MBq) constituted criteria for disease recovery. The following parameters were considered: age, sex, histology, TNM, surgery, delay between surgery and first iodine treatment, baseline TSH, Tg, and antibodies values, administered activities, 2h and 24h remnant uptake, 24h and 44h whole-body dismissing activity, post-therapies whole body (WBS) findings (neck involvement with or without cervical lymph nodes; mediastinum; lung and bone), 6 and 12 months follow-up TSH and Tg values, disease free time between the two treatments, pre-II therapy TSH and Tg values as well as Tg delta values. Results: 27 of 76 Pts did not respond to repeated radioiodine treatments being averaged Tg values at follow-up 82 ± 41 ng/ml, whereas 50 had disease recovery further confirmed. At logistic regression analysis bone involvement at first post-therapy WBS (Odds ratio; OR: 6.84) and lung (OR:6.31) and bone (OR:2.1) involvement at second post-therapy WBS were recognized as powerful parameters in predicting no disease response following repeated I-131 therapies. None of remaining clinical and laboratory data showed a predictable value. In addition, delay between surgery and first I-131 treatment (11±24 months) was demonstrated to predict patient outcome (OR:1.07/months). Conclusion: Our findings indicate that in Pts with DTC receiving repeated radioiodine treatments, bone involvement at first post-therapy WBS, lung and bone involvement at second post-therapy WBS as well as delay time between surgery and first I131 therapy represent the most significant parameters in predicting Pts outcome irrespective of others clinical, histological and instrumental data.

P516 Should “low-risk” thyroid cancer patients with residual thyroglobulin be retreated with iodine 131 ? E. Hindie1, P. Zanotti-Fregonara1, F. Duron1, I. Keller1, J. Moretti2, J. Devaux1; 1St Antoine hospital, paris, France, 2St Louis hospital, paris, France. The recent consensus statement on patients with low-risk thyroid cancer suggests repeat 131I therapy if the Tg (thyroglobulin) value is elevated at first follow-up. We evaluated this strategy in our practice.Methods: Among 407 patients with thyroid cancer who had total thyroidectomy and 131I ablation between January 2000 and December 2003, 12 low-risk patients (mean age

S329

Poster Presentation

M. E. Toubert, A. Dib-Deperrest, E. Hindie, J. L. Moretto; Hôpital SaintLouis, Paris Cedex 10, France.

131

32.8 y) were retreated on the basis of their Tg level at first follow-up. Tg levels “off-T4” ranged between 4.5 and 251 ng/mL (median 8). One to four courses of 3.7 GBq 131I were given.Results: Three patients had a negative 131I therapy scan and an uneventful course. Two patients had slight residual uptake in the thyroid bed and negative ultrasound examination. Four patients had isolated 131I uptake in the mediastinal region. No abnormalities were found on complementary mediastinal imaging. This finding was interpreted as benign 131I thymic uptake. The last three patients also had mediastinal thymic uptake associated with a slight thyroid bed uptake. One patient had a gradual increase in the Tg level, and underwent resection of nonfunctioning neck lymph nodes. Tg levels declined in all other patients.Conclusions: No distant lesions were found in a group of “low-risk” thyroid cancer patients given empiric 131I therapy for residual Tg. Thus, blind 131I therapy should be used with parsimony in young patients.

P517

determination were 81%,61% and 73%.If results of J-131 WBS and Tg were taken into consideration,sensitivity reached 95%,specificity 100% and accuracy 98%.Conclusions:The management and follow up of patients with differentiated thyroid carcinoma diagnostic J-131 WBS is essential since Tg measurement alone can not replace J-131.Using both J-131 WBS and Tg as diagnostic tools in search for metastases and reccurence of the disease gives much better accuracy.

P520 I-131 therapy in differentiated thyroid carcinoma patients with high thyroglobulin levels despite negative diagnostic I-131 scans

Short term outcome of differentiated thyroid cancer patients in Kosova

A. Akgun, B. Yazici, O. Erdim, Z. Ozcan, H. Ozkilic; Ege University Medical Faculty Department of Nuclear Medicine, Izmir, Turkey.

I. Gerqari, 19571, N. Rizvanolli, 19562, R. Miftari, 19613, L. Abdullahu, 1 19643; Diagnostika plus&University clinical Center, Prishtina/Kosova/UNMIK, Serbia and Montenegro, 2Diagnostika plus, 3 Prishtina/Kosova/UNMIK, Serbia and Montenegro, University clinical Center, Prishtina/Kosova/UNMIK, Serbia and Montenegro.

Aim: Serum thyroglobulin (Tg) is widely used as a tumor marker for monitoring of differentiated thyroid cancer (DTC). There is well correlation between serum Tg levels and I-131 whole body scan (WBS) findings after thyroid ablation. However it has also been shown that elevated serum Tg levels may be found despite the negative I-131 WBS.Materials and Methods: We retrospectively reviewed series of 1210 patients with DTC followed in our department between 1996 and 2006. We focused on 63 out of the patients (5.2%) who had high levels of Tg in the post-surgical follow-up. The mean Tg level was 259,41 ± 192,76 ng/ml (range: 20,3-520). In 23 of 63 cases WBSs showed no abnormal foci. The female/ male ratio was 13/10 and the mean age was 52,4 (range: 16-82 yrs). The mean follow up was ranging form 6 to 144 months (mean: 53,7).Results: The distribution of histologic diagnosis was papillary carcinoma in 18, follicular carcinoma in 2, hurtle cell carcinoma in 2 and mixed carcinoma in 1 patient. Fourteen of these 23 patients received empirically high-dose I-131 treatment on a total of 28 occasions. The mean application dose was 175 ± 25,7 mCi. At the end of follow-up, post-therapeutic WBSs and Tg levels were comparatively reviewed. Post-therapeutic images revealed pathologic iodine uptake in 11 (neck: 6, thorax: 5) of 28 high-dose WBSs. Up to now, while Tg levels decreased more than 15 % decreased in 6, no change was noted in 8 and increased levels in 3 RAI applications. No death related to the thyroid cancer was observed.Conclusions: In this clinical series of patients with aggressive tumors who had very high Tg levels despite the negative diagnostic iodine scan, no clear evidence of relation between positive high-dose post-therapeutic WBSs and Tg levels were noted. It is thought that empiric high-dose I-131 treatment may only be effective in a small number of patients with increased Tg levels despite the negative iodine WBSs.

OBJECTIVE:The aim of this study was to evaluate the usefulness of the radioiodine 131 therapy administered on the basis of raising serum Tg level and the Whole Body Scan.Methods: All the patients were treated with total or near total thyroidectomy and 131 I ablation,18 patients (16 women and 2 men) with differentiated thyroid cancer (15 with papillary and 3 with follicular cancer).All the patients showed the detectable serum tg level on TSH suppressive therapy.The 131 I further therapy was scheduled (range 3.0-6.0 Gbq) after 6-9 months.Five to seven days after the radioiodine therapy the patients underwent the 131 I post therapy whole body scan.The serum Tg level at 6-9 months after 131 I therapy was evaluated as an indicator for short term response to radioiodine.Results:All the patients were evaluated 6-9 months after the first 131 I therapy.Post therapy WBS showed residual activity in 6 patients,regional local recurrence in 10 patients and the distant metastasis in bones were identified in two patients.After 6-9 months,of 18 of tham 5 patients had the Tg value <1.5 ng/ml,11showed a Tg decrease at least 50% and two patients did not show any decrease of Tg but one of them had negative WBS.Conclusions:The detection of local recurrences were much better visualized at post 131 I therapy WBS.The administration of therapeutic 131 I on the basis of elevated Tg levels has a good effect in the short term outcome.

P518

P42 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Impact of aditional radioiodine treatment in well differentiated thyroid carcinoma in patients with negative whole-body scan and high thyroglobulin level

Radionucl.Therapy/Dosimetry - Clinical: Thyroid, Bone Pain Palliation & Miscellaneous 2

C. Rocha, F. Vieira, G. Costa, A. Albuquerque, D. Freitas, F. Silva, A. Ferrer-Antunes, J. Pedroso de Lima; Hospitais da Universidade de Coimbra, Coimbra, Portugal.

P521

Aim: During the follow-up of patients with well differentiated thyroid carcinoma, even without radioiodine accumulation on whole-body scan (negative WBS), a high level of the serum thyroglobulin (Tg) may justify an additional treatment with radioiodine. However this procedure is controversial and is not accepted by all authors. The aim of this study is to evaluate if the treatment with radioiodine in this group of patients have a positive effect in decreasing of thyroglobulin level.Materials and Methods: Twenty patients were included in this study. All patients revealed a negative diagnostic WBS and a high serum thyroglobulin level before the treatment with radioiodine. Post-treatment WBS was performed 7 days after the treatment. Six months after the treatment, measurements of serum thyroglobulin levels were made in all patients by IRMA.Results: We found a decrease of the serum thyroglobulin levels in 12 of 20 (60%) patients. Post-treatment WBS did not revealed radioiodine abnormal accumulation in 15 of 20 (75%) patients (negative WBS). In this group of 15 patients, 9 of them (60%) had a decrease of the serum thyroglobulin levels 6 months after the treatment with radioiodine. In the remainder 5 patients we observed a positive post-treatment WBS, with abnormal radioiodine accumulation in lungs and/or neck. Among those patients, 3 (60%) had a decrease on thyroglobulin levels.Conclusions: In patients with a negative WBS and elevated serum thyroglobulin levels, the treatment with radioiodine may have a beneficial therapeutic effect. This seems to be valid for the patients with a positive post-treatment WBS as well as for those with a negative posttreatment WBS.

P519 Importance of J-131 whole body scan in post operative folowup of differentiated thyroid carcinoma Z. I. Petrovski; Clinical Hospital-Bitola, Bitola, The Former Yugoslav Republic of Macedonia. Aim:To assess the efficiency of J-131 whole body scan(WBS) with diagnostic dose was compared with thyroglobulin(Tg) values in the post operative follow-up of patients with differentiated thyroid carcinoma.Materials and Methods:Sixty two operated patients,49 female(36+-18yrs) and 13 male(30+-16yrs) with well-differentiated thyroid carcinoma(43 papillary,19 follicular) were scanned.The patients were imaged after administering a diagnostic J-131 dose of 111-260MBq.Images were diagnosed for the presence and the intensity of thyroid lesions.J-131 WBS was performed for the first time after total thyroidectomy and radioiodine ablation of thyroid remnant,after that once a year under hypothyroid conditions(TSH>3omU/ml).in the interium,we pwrfomed Tg measurement and hight-relosution ultrasound of the neck.The sensitivity,specificity and accuracy of Tg levels for diagnosis of tumor residue or metastases were calculated and compared with results obtained by diagnostic J131 WBS.Results:From 54 consecutive patients who had complete remission,tumor recurrence or metastases were detected:5/54(9,2%) only by J-131 WBS;in 3/54(5,5%) only by Tg measurement;in 7/54(11,1%) by both methods.The sensitivity,specificity and accuracy of diagnostic J-131 WBS were 77%,100% and 83% respectively,where as for the Tg levels

S330

The use of TgAbs as a marker in differentiated thyroid cancer after ablation theraphy B. Yazici, A. Akgun, O. Erdim, U. Duygun, H. Ozkilic; Ege University Medical Faculty Department of Nuclear Medicine, Izmir, Turkey. Aim: Thyroglobulin (Tg) is a glycoprotein that is produced exclusively by normal thyroid follicular cells or well-differentiated thyroid cancer cells. Serum Tg level is a sensitive and specific marker used in the management of patients with differentiated thyroid carcinoma (DTC). However serum Tg measurements may be affected in DTC cases with positive thyroglobulin autoantibodies (TgAbs).The aim of this retrospective study was to evaluate TgAbs variations before and after total thyroid ablation and to correlate Tg and TgAbs serum levels to the outcome of disease.Materials and Methods: We retrospectively reviewed series 538 patients with DTC followed in our department between 2001 and 2006. We focused on 18 patients (3.35 %) who had high levels of TgAbs in the post-surgical follow-up. There were 16 female and 2 male patients and the age range was 24-70 years. The study group included 16 papillary and 2 follicular carcinoma pts. The detailed histologic examination revealed lymphocytic and hashimoto thyroiditis in 7 of 18 (38.9 %) pts. The follow up was ranging form 12 to 56 months (mean: 25.15). Serum Tg and TgAbs were measured using immunoradiometric assay technique. All Tg and TgAbs levels were obtained when the patient is off thyroid hormone therapy. The amount of I-131 administered ranged from 30 to 175 mCi (mean, 175±24.93mCi).Results: Successful ablation was achieved in 16 of 18 (88.9 %) patients. TgAbs serum levels reduced more remarkable than Tg serum levels after successful thyroid ablation (Tg 0.81±1.34 ng/ml 0.14±0.27 ng/ml p>0.05 TgAbs 393.89±211.91 IU/ml 143.41±76 IU/ml p<0.05). During followup TgAbs was normalized in 15 patients (all were considered tumor-free). While TgAbs remained persistently elevated in 3 cases, no evidence of disease progression was documented in these patients.Conclusions: These data indicate that serial TgAbs serum levels may be used as an indicator showing the efficacy of ablation therapy in patients with positive TgAbs in DTC.

P522 Successful I-131 Treatment of brain metastases of radiation induced childhood thyroid carcinoma. J. Biko1, Y. Demidchik2, C. Reiners1; 1Clinic and Policlinic of Nuclear Medicine, Würzburg, Germany, 2Department for Onkology, Belarusian State Medical University, Minsk, Belarus. Aim: Differentiated thyroid carcinomas can be subdivided into the papillary and follicular types. The routes of metastatic tumor spread of these two types differ; papillary carcinomas spread primarily via lymphatic system whereas follicular carcinomas tend to metastasize via the bloodstream. Hence papillary carcinomas spread preferentially to regional lymph nodes and through the lymphatic system to the lungs, in follicular carcinomas mainly lungs, bone and live rare affected. Cerebral metastases to the brain are very rare in differentiated thyroid cancer.

P523 Radioiodine therapy of differentiated thyroid carcinoma and recurrences of disease L. Stefanovic, J. Mihailovic, M. Malesevic, K. Nikoletic; Oncology, Sremska Kamenica, Serbia and Montenegro.

Institute of

The appearance of recurrence in patients (pts) with differentiated thyroid carcinoma (DTC) decreases the probability of favorable outcome of this malignancy. Aim of the study is to analyze the influence of radioactive iodine (RAI) therapy and other factors on the frequency of recurrences. Patients and methods: 363 pts were treated by RAI from 1977 till the end of 2000. They were followed to the end of 2005. The retrospective analysis was applied on the data of 351 pts; 12 pts were lost to follow-up. Mean time + standard deviation (SD) of follow-up was 8.4+4.5 years, median 7.2 years, range 2 months to 36.4 years. Descriptive statistics, Cox regression and Kaplan-Meier method were used in data analysis. Results: The remission of disease after initial treatment was attained in 306 pts. Recurrences developed in 86 (28.1%) of them, in the range of 6 months to 21.5 years after initial therapy, mean + SD 5.7+4.5 years, median 5.0 years. Recurrences were very significantly dependent from the initial therapy - they were infrequent if initial therapy was adequate surgery and RAI therapy, and they were the most frequent if the initial treatment was insufficient surgery only (partial thyroidectomy, loboisthmectomy, etc.) (p<0.0001). When the result of initial therapy was remission, the largest group of these pts was constituted from pts treated by adequate surgery and RAI therapy (222 pts); the probability of remission persistence, without recurrences, in this group was 0.891+0.022 five years after initial therapy, and 0.765+0.04 after 15 years. The probability of recurrences was very significantly more frequent, besides the initial therapy, if tumor did not accumulate RAI (p<0.0001), if remission was partial after initial therapy (p<0.0001), if pts were > years old (p=0.0001) and if TNM stage of disease was more advanced (p=0.0002). The pathohistologic type of tumor and gender of pts had no significant influence on the onset of recurrences (p=0.1443 and p=0.9487, respectively). The probability of survival 5 years after appearance of recurrences was 0.564+0.065 only. Conclusions: The onset of DTC recurrences after initial therapy is significantly diminished if RAI therapy is applied immediately after adequate surgical treatment. It is necessarily to repeat this treatment until complete remission of disease is reached, in exception if tumors do not accumulate RAI, when other modalities of treatment are necessary. The reduction of recurrences is very important, because dramatic deterioration of disease is in relation with their appearance, often with disease related death.

P524 Clinical significance of serum thyroglobulin measurements after total thyroidectomy in the patients with differentiated thyroid carcinoma. A. Kowalczyk, M. Konieczna, G. KamiĔski; Services, Warsaw, Poland.

Military Institute of Health

Serum thyroglobulin (Tg) play an important role in management of patients with differentiated thyroid carcinoma (DTC) after total thyroidectomy (TT) followed by radioiodine therapy (RIT). The aim of our study was to assess the diagnostic value of serum Tg measured after TT and just before RIT. Material and methods. The study group consisted of 136 patients (20 male and 116 female) undergone TT because of DTC (16 follicular and 120 papillary carcinoma). All measurements were performed 4 weeks after surgery or thyroid hormone withdrawal. On the basis on retrospectively analysed results the patients were divided into 3 groups: 1) 24 patients after not complete (unintentional) thyroidectomy (TSH<30uIU/ml and/or 24h thyroid bed uptake - U24>20%) 2) 101 patients after complete thyroidectomy and no evidence of distant metastases 3) 11 patients after complete thyroidectomy, with lung, bone or lymph node metastases Values of serum Tg, antithyroglobulin antibody (AbTg), TSH concentration and U24 were determined and compared between groups using statistical analysis. Results. The results are shown in Tab.1. Mean U24 was significantly higher in group 1 than 2 and 3. There was no difference between group 2 and 3. Mean TSH concentration was signifficantly different between the groups: in group 2 higher than 1 and 3 and in group 3 higher than 1. Two patients of group 1 (8,3%), eight patients of group 2 (7,9%) and four patients of group 3 (36,3%) had an elevated levels of AbTg. In the rest of patients, mean serum Tg was significantly higher in group 3 than 1 and 2, as well as in group 1 than 2. Conclusions. Serum Tg concentration measured after TT can be useful for evaluation of effectiveness of surgery and presence of undiagnosed metastases. Increased serum AbTg concentration, even if coexists with low serum Tg, can be connected with distant metastases.

Tab.1. Mean values of analysed parameters TSH (uIU/ml)

U24 (%)

Tg (ng/ml)

group 1

18,2

24,6

16,2

group 2

76,6

3,9

5,0

group 3

38,1

3,0

423,9

P525 Alternative medicines and thyroid cancer therapy V. R. McCready1, U. Werneke2; 1Hammersmith Hospital and Institute of Cancer Research, London, United Kingdom, 2Homerton University Hospital,, London, United Kingdom. Aim Nearly 50% of cancer patients are known to take alternative medicines and those who do probably take more than the recommended doses in the hope of having a palliative effect on their cancer. The potential interactions between these and radiopharmaceuticals have been reported. In patients with differentiated carcinoma of the thyroid, it is particularly important to know about the iodine content of alternative medicines. In many cases the presence of iodine is obvious while in others the name of the preparation does not immediately indicate the presence of iodine nor the amount present. The aim of this study was to determine the frequency of iodine containing preparations and study the iodine levels in natural health products.. Methods The preparations marketed by a large national natural products company was surveyed to discover the frequency of iodine containing preparations, and to analyse their iodine content. The preparations were divided into those which obviously contained iodine, vitamin preparations, and others prescribed for a variety of situations where supplements were marketed for the skin, nails, eye, male and female ‘problems’. Results 42 separate iodine containing preparations were identified including vitamin preparations (20), kelp (3), womens’ and mens’ preparations (7), and others (12). The recommended daily allowance (RDA) of iodine is 150 µg. Three kelp preparations contained 150 µg iodine per tablet. Four multivitamin preparations contained 150 µg iodine and one, 100 µg per tablet while three KLB6 softgel preparations contained natural occurring iodine and a KLB6 tablet 33.3 mg. Preparations specifically designed for women contained between 75 micrograms and 150 micrograms and similarly that for men contained 150 µg. Other preparations containing iodine included a multmineral tablet (75 µg), tablets for ‘skin, hair and nails’ (112.5 µg), an athlete’s formula (112 µg), a preparation for eye vitality 100 µg. Conclusions It is clear that many alternative medicines contain the RDA of iodine and if these are taken as recommended or more likely in larger quantities, then this iodine would compromise radioiodine uptake. Unless the very small print of the contents are examined it would not be obvious that many of the preparations contain iodine. It is important to ensure that alternative medicines are not the cause of radioiodine negative scans. Reference Werneke U, McCready VR.Complementary alternative medicine and nuclear medicine.Eur J Nucl Med Mol Imaging. 2004 31:599-603

P526 Surgical completeness in patients submitted to videoassisted thyroidectomy (VAT) for differentiated thyroid cancer (DTC) M. Salvatori1, P. Castaldi1, M. L. Maussier1, V. Rufini1, P. Princi2, A. G. Spaventa2, M. Raffaelli2, C. P. Lombardi2, R. Bellantone2; 1Nuclear Medicine, Rome, Italy, 2Endocrine Surgery, Rome, Italy. Aim: VAT has some advantages over conventional surgery in terms of cosmetic results, postoperative pain and recovery. The aim of the present study was to evaluate the completeness of the surgical resection and 131I ablation (RAI) efficacy in patients submitted to VAT for DTC.Materials and Methods: 198 patients (172 F and 26 M; mean age 43.4+12.9 yrs) underwent VAT between Sept. 2000 and Nov. 2005 for papillary thyroid carcinoma (PTC) (53 pts), suspicious/indeterminate thyroid nodule (140 pts.) and toxic goiter (5 pts.). Total thyroidectomy was performed in 177 pts., lobectomy in 21 pts with completion by VAT in 14 cases. Central compartment node dissection was performed in 15 pts and therapeutic lateral neck dissection in 2 pts. Final histology showed PTC in all patients and co-existing papillary and medullary microcarcinoma in 1 pts. According to TNM staging, 155 pts. (78.3%) were pT1, 20 pts. (10.1%) pT2, 22 pts. (11.1%) pT3, and 1 pt. (0.5%) pT4. Altogether 18 (9.1%) pts. were N1a e 2 (1%) were N1b. 57 pts. were submitted to 131I ablation (RAI) (mean activity 2.4+1.1 GBq, range 1.35.6 GBq) with post-therapy WBS (TxWBS) performed before the patient’s discharge; 67 lowrisk pts. were evaluated by diagnostic WBS (DxWBS) and TSH-stimulated thyroglobulin (Tg), without RAI; the remaining 74 pts. were followed in other Institution. The completeness of surgery was evaluated by qualitative Tx WBS or DxWBS , quantitative 131I neck uptake (RAIU) and TSH-stimulated Tg levels. The RAI efficacy was performed 6-10 mo. later by DxWBS, RAIU and Tg.Results: Thyroid remnants were present in all valuable pts, except 6 cases (4.8%) that showed negative DxWBS, RAIU < 1% and undetectable Tg, so suggesting a real total thyroidectomy. Among the remaining 118 pts. (95.2%), thyroid remnants were observed by TxWBS and DxWBS in 57 and 61 cases, respectively. In these pts. mean neck RAIU and Tg values were 2.7+4.7% (range 1.3-9.5%) and 7.3+12.5ng/ml (range 2.8-79.8), respectively. The ablation efficacy was evaluated in 42 out of 57 pts.; negative DxWBS, undetectable Tg and a mean RAIU of 0.3+0.5% suggested a successful ablation rate in 35/42 pts. (83.3%).Conclusions: Our results show that both the completeness of the surgical resection and the successful ablation rates are comparable to that reported for conventional surgery. VAT is safe and practicable in pts. with DTC but a longer follow-up is necessary to draw definitive conclusions about the clinical outcome.

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Poster Presentation

Radiation induced thyroid carcinomas in children mainly display a papillary growth pattern.Materials and Methods:16 year old female patient with from Gomel area, Belarus exposed to radiation from Chernobyl accident, papillary thyroid carcinoma (follicular variant) pT4 N1a M1 (lungs, brain); thyreodectomie 08/92; 6 courses of radioiodine treatments (RIT) (every 6-8 months 100 MBq/kg body weight) and afterwards three I-131 whole body diagnostic scans (every 12 months 300 MBq) with a cumulative activity of 27.3 GBq I-131. Whole body scans (PT-scan) were performed 4-5 days after I-131 administration on a Siemens E.cam dual head gamma camera; magnetic resonance imaging on a Simens Magnetom Open of the head before and after i.v. contrast enhancement (gadolinium DTPA). F-18-FDG PET study on a Simens ECAT Exsact-Scaner. Observation period from 04/1999 until 12/2004.Results: A good agreement between the results of the PT-scan and the MRI of the head was noted. The PT scan displayed increased I-131 uptake in the left side of the cerebellum and in the right hemisphere temporal, which was interpreted as cerebral metastases. After 3 courses of RIT with a cumulative activity of 15.6 GBq I-131 the pathological cerebral focuses of increased I-131 were no more metastases seen in the PT-scan; cerebral MRI displayed a complete remission of the cerebral. Also, the PET study (performed October 2002) revealed no evidence of pathological foci, especially in respect to the brain. During the whole period of observation the patient did not have any neurological symptoms. Further radioiodine treatments were necessary to treat the coexisting pulmonary metastases. The tumor marker thyreoglobulin showed during the observation period a continuous decrease.Conclusions: Brain metastases are a rare observation in radiation induced thyroid cancer. However in the case of I-131 uptake a successful therapy is possible.

P527 Success of radioablation of thyroid remnants after total thyroidectomy for differentiated thyroid carcinoma A. Szikszai, C. Stefes, T. Kuwert; Erlangen, Germany.

University of Erlangen-Nürnberg,

Numerous data have been published with regard to the dose of radioiodine needed for complete ablation of thyroid remnants after surgery for differentiated thyroid carcinoma. The aim of this retrospective study was to analyze which parameters predicted success of that procedure..Methods: Between January 1999 and December 2004 189 patients received radioablation after thyroidectomy in the Clinic of Nuclear Medicine of the University of Erlangen-Nürnberg. In all of these cases, thyroid carcinoma had been histologically proven. The clinical charts of these patients were reviewed and, information on their tumor stage, the dose of radioiodine used, the blood concentrations of TSH, T3, T4, and thyroglobulin at the time of radioablation, the 24 h uptake of radioiodine determined before radioablation, and the dose rates determined at 100 cm from the patients´ neck using a Geiger-Mueller counter retrieved. From this group of patients, 129 patients meeting the following predefined criteria were chosen for further analysis: a) Radioiodine ablation two to eleven weeks after thyroid surgery b) Ablation dose beetwen 2.18 and 4.93 GBq 131-Iod c) No distant metastasis known prior to or at time of radioablation d) No use of recombinant human TSH for radioablation e) No anaplastic carcinoma In this group of patients, we assesed the intensity of cervical radioiodine accumulation on the posttherapeutic scan using a 4-point scale. Outcome variable was the presence or absence of uptake of radioiodine in the neck investigated by radioiodine scintigraphies performed after radioablation (average 188 days).Results: In 58 % of the patients, complete radioablation of the thyroid gland was achieved. There was no significant difference between patients with and without persistence of thyroid remnants with regard to the dose of radioiodine used, the 24 h uptake of radioiodine determined before radioiodtherapy, the cervical dose rates measured 1, 2 , and 3 days after therapy, serum fT3, and the intensitiy of radioiodine uptake visually assessed after radioablation. Both groups differed, however, significantly with regard to TSH (p < 0.05), serum fT4 level (p < 0.05), and serum thyroglobulin (p < 0.001).Conclusions: Although fairly high doses of radioiodine were used for radioablation, a successful radioablation was achieved only in roughly 60% of the patients. The pretherapeutic serum level of thyroglobulin and - to a lesser extent - also that of TSH and T4 correlated significantly with success of radioablation. Further prospective studies should assess the utility of these parameters for individual dosage of radioiodine.

P528 The stunning effect is not always avoided, even if the ablation therapy is performed immediately after the 185 MBq I-131 diagnostic whole body scan. A. T. Georgakopoulos, S. P. Saranti, E. M. Trivizaki, D. A. Antoniou, L. A. Iordanidou, P. I. Natsis, K. M. Pateniotis, P. T. Koutsiouba; METAXA'S Memorial Cancer Hospital, Piraeus, Greece. Recent debates have been published about the evidence of stunning effect on the substantial I131 ablative therapy after a diagnostic I-131 dose for DTC patients. Questions such as the existence of the stunning effect, the necessity and the recommended dose of a prior I-131 diagnostic scanning, the time interval between the diagnostic and the therapeutic dose have not been cleared yet. AIM: to determine if there is any impact of the 185 MBq diagnostic I-131 dose on the early following( < 45 days) therapeutic I-131 dose and if the time interval between them affect the presence of stunning.Materials and Methods: The study included 24 patients ( 2 men, 22 women, mean age 46.6 years) with total/near total thyroidectomy for differentiated thyroid carcinoma. The patients were given a 185 MBq diagnostic and a 3700 MBq ablative I-131 dose with a time interval of 3-45 days between them. The patients were classified into 3 groups according to the time interval between the diagnostic and the therapeutic administration (Group A of 14 pts with a 3 days time interval, Group B of 7 pts with a 7-17 days and Group 3 of 3 patients with 30-45 days). A qualitative and a quantitative estimation were performed for the diagnostic and post therapy scanning on the 3rd and 7th day respectively.Results: Stunning phenomenon was produced totally for 14 of the 24 (58.3 %) patients (9/14 patients of Group A, 3/7 patients of Group B, 2/3 patients of Group C). There was not found any difference between the qualitative and the quantitative estimation of stunning effect. Statistical analysis of stunning density between the 3 groups was not possible to be done because the number of stunned patients for groups B and C was too small and this parameter remains under evaluation..Conclusions: According to our results stunning phenomenon may be produced for patients who were given a therapeutic I-131 dose in a 45 days interval from the 185 MBq diagnostic I-131 dose. Stunning phenomenon could not be prevented by preserving a 72 hours time interval between the diagnostic and the ablative iodine-131 dose. Differentiation of stunning density between stunned patients with different time interval is a parameter that has to be evaluated.The possible impact of the different time interval to the therapeutic efficacy of iodine therapy for the stunned patients is one critical question that must also be evaluated.

P529 Thyroid cancer radioidine therapy using recombinant human TSH V. Voliotopoulos, C. Antypas, A. Filou-Giougi, E. Pantelis, I. Valais, A. Stavraka-Kakavaki; Iatropolis Magnitiki Tomografia S.A, Athens, Greece. Purpose : The use of recombinant TSH (Thyrogen) has already entered in the clinical routine in order to avoid the discomfort and the morbidity associated with the withdraw of thyroid hormone. Methods and Materials: We used the recombinant Human TSH in 20 patients )age >50 yrs) totally or near totally thyroidectomized who came in our clinical to receive radioiodine therapy for locally invasive differentiated thyroid cancer.All patients were treated,while euthyroid on L-T4 ,after rhTSH administration with two consecutive daily injections (0,9mg)of rhTSH .Half of them underwent diagnostic-before therapy diagnostic whole body scan using again rhTSH administration and after that iodine therapy using and identical second cousre of rhTSH.Results: Administration of thyrogen promoted I-131 therapy uptake in all patients as

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demonstrated with the after therapy whole body scan.As known the administration of rhTSH increase the sensitivity of the Tg(Thyroglobulin) concentrations measurments.About 12 months after therapy we performed whole body scan and we shaw a comlet remission of the residual sites and in two patients reduction in one metastatic site.Conclusions: Administration of rhTSH is safe and a very usuful tool for inducing I-131 uptake in local or metastatic of differentiated thyroid cancer avoiding L-T4 withdrawal.

P530 Radioidine kinetic after the administration of recombinant human TSH for thyroid cancer therapy V. Voliotopoulos, C. Antypas, E. Pantelis, A. Filou-Giougi, I. Valais, A. Stavraka-Kakavaki; Iatropolis Magnitiki Tomografia S.A, Athens, Greece. Purpose: Recombinant human thyroid stimulant hormon (rhTSH) is used for exogenous thyroid stimulation before diagnostic I-131 scintigraphy as well for iodine therapy in thyroid cancer. Methods and Materials: We compared the results of group A (20 patients) who recieved therapy after the use of recombinant TSH , with a group B (30 patients) whorecieved radioidine therapy after thyrixine withdrewl(TSH level>35).All patients followed a low iodine iodine diet.None of them received radiographic contrast agent at least two months before therapy and all patients received 2 doses of 0,9mg of recombinant human TSH (rhTSH).Results: The effective half life of I-131was significantly prolonged after endogenous stimulation (0,43days for group A vs 0,53 days for group B).The main initial dose rate was significantly lower in euthyroid and rhTSH group (10,7+/_12,6 Gy/H),compared to the hypothyroid group (27,1+/_42,5 Gy/h).Conclusions: The use of rhTSH for iodine therapy reduses the effective half life of I131.This is mainly due to reduced renal iodine clearance in hypothyroid state.

P531 The efficacy of I-131 ablation therapy for stunned and nonstunned patients S. P. Saranti, E. M. Trivizaki, L. Iordanidou, A. T. Georgakopoulos, D. Antoniou, P. Natsis, E. S. Matselas, P. T. Koutsiouba; Metaxa’s Memorial Cancer Hospital, Piraeus, Greece. If we accept the existence of stunning, a major question that can arise concerns the incidence of this phenomenon to the I-131 therapeutic efficacy. AIM: to assess if stunning phenomenon caused by a 185 MBq diagnostic I-131 dose has any impact upon initial I-131 ablation therapy to patients with well differentiated thyroid carcinoma (DTC).Materials and Methods: Among the patients treated with iodine-131 the last 2.5 years, 73 DTC patients (15 men, 58 women, mean age 49.5 years) with total or neartotal thyroidectomy received a first ablation therapy. Between these 73 patients, the 24 - who received the ablative therapy within two months from the first diagnostic I-131 WBS- were further evaluated with post ablation scan and among them 13 produced stunning. So, based on the experienced stunning effect, we divided our patients in two groups: Group I with 60/73 nonstunned patients and group II with 13/73 stunned patients. Furthermore by histology group I included 45 papillary and 15 papillary/follicular and group II included 11 papillary and 2 papillary/follicular cancers. All patients had a first 185 MBq diagnostic I-131 WBS (DxWBS) several days to months prior to first ablation therapeutic dose and a second I-131 DxWBS was performed six months post therapy. The mean follow-up period of time was 14 months (range 7 to 30 months). By definition the patients were considered successfully treated if no functioning thyroid tissue was observed in the 6 months post-ablation DxWBS.Results: Ablation with the initial I-131 therapy dose was achieved in 38/60 (63.3%) of nonstunned patients (group I) and 7/13 (53.8%) of stunned patients (group II), an almost significant difference. The 38 single ablation dose responders of group I were 30 papillary and 8 papillary/follicular while the 7 single ablation dose responders of group II were only papillary cancers.Conclusions: According to our results there is a slight superiority of the I-131 single ablation therapy for the nonstunned patients and there is a better response of papillary cancer to the initial ablation dose. It remains to be further studied in a larger number of patients.

P532 Radio-guided surgery with radioiodine for local and regional recurrences of differentiated thyroid cancer M. Salvatori1, P. Castaldi1, D. Dambra1, L. Lo Conte1, V. Rufini1, M. Maussier1, G. Ardito2; 1Nuclear Medicine, Rome, Italy, 2Endocrine Surgery, Rome, Italy. Aim: To determine the usefulness of radioiodine (131I) and a gamma probe for radio-guided surgery (RGS) to identify and then radically remove local and regional recurrences in patients with differentiated thyroid cancer (DTC).Materials and Methods: The present study included 15 DTC patients (10 men and 5 womens; mean age 47.5 years) all with persistent or recurrent 131Ipositive lymph node metastases after previous total thyroidectomy and at least two131I treatments. The protocol was designed as follows. Day 0: all patients received 3.7 GBq of 131I, 13 of them in the hypothyroid condition and 2 after rh-TSH (Thyrogen ©). Day 3: presurgery whole-body scan (WBS). Day 5: neck surgery using a gamma probe (Navigator GPS, AutoSuture, Italy), recording the absolute counts (AC) and the lesion/background counts (L/B) ratio. Day 7: post-surgery WBS performed using the remaining 131I activity.Results: Post-surgery WBS showed a negative pattern in 11 out of 15 patients, suggesting the efficacy of the surgical procedure in most of the cases. The mean pre-excision AC and the mean L/B ratio obtained by placing the probe in direct contact with all the pathologic sites were 179.3 counts per second (range 18-553 cps) and 12.3 (range 2.75-27.6), respectively. The mean post-excision AC and L/B ratio obtained by placing the probe in the bed of the removed lesion were 29.6 cps (range 4-49 cps) and 2.03 (range 0.84.1), respectively. The surgeon judged the procedure to be decisive in 3 patients, favorable in 9, and irrelevant in 3. The final histologic examination showed the presence of 111 lymph node metastases, 49 detected by both WBS and gamma probe, 56 only by gamma probe, and 6 revealed only at histologic examination.Conclusions: RGS permitted us to detect and then dissect in a single session local and regional recurrences, often difficult to reveal because inside sclerotic areas or behind vascular structures. Moreover it allows to obtain a more accurate surgical result with low levels of radioactive exposure to the surgeon’s hands and without significant lengthening of the normal operating times, increase in morbidity or surgical complications.

Radioiodine therapy in patients with Graves’ disease shortterm outcome S. S. Abdelrazek, F. Rogowski, P. Szumowski, A. ParfieĔczyk, A. Zonenberg, A. Sawicka; Medical University of Bialystok, Bialystok, Poland. Summary Aim of the study: Several therapeutic options are available for the treatment of Graves’ disease including long term antithyroid drug near-total resection and radioiodine therapy. Radioiodine therapy is the treatment of choice in Graves' disease after unsuccessful antithyroid drug medication, occurrence of side effects from antithyroid drugs or an increased risk from surgery. Our aim was to evaluate the factors (patient preparation, effective half-life, administered activity and dosimetry) that influence radioiodine treatment outcome.Materials and Methods: During 9 years periods in our department we treated 950 patients with Graves’ disease: aged 18-65 years, 85% of them were female and 15% male. Qualification of these patients was based on clinical features, high levels of serum fT3 and fT4, low levels of serum TSH and characteristic appearance on thyroid scans and ultrasound. All the patient treated unsuccessfully with antithyroid drugs for 0.5-2 years. Most of patients were well prepared with antithyroid drugs and were in euthyroid state, serum TSH levels were more than 0.1 mU/l. In most of the patients sever Graves’ opthalmopathy excluded by opthalmological examination, 5% of the patients treated with glucocorticoids prophylactic. We have treated the hyperthyroid patient if the effective half-life measured by the use of T24 and T48 was more than 3 days. The activity dose was calculated by the use of Marinelli’s formula and ranged between 200-800 MBq. The absorbed dose (Gy) ranged between 100-240 Gy and was proportional to thyroid volume. Follow up control done every 6 weeks. Repeated radioiodine therapy if indicated was given after 6 months of the first dose.Results: The success of treatment was: 71% of patient achieved euthyroidism after one dose of radioiodine therapy, 10% after 2 doses of therapy, 1% need more than two doses to achieve euthyroidism, 18% of patient develop hypothyroidism,Conclusions: Radioiodine therapy can consider as safe appropriate, cost-effective therapy and showed a satisfactory short-term outcome in Graves’ disease. Good preparation of patient; individual dosimetry to determine the therapeutic activity (measured absorbed dose and effective half life); and well organised follow up will help to decrease the numbers of cases of hypothyroidism and relapse of hyperthyroidism. Key Words: Graves’ disease, radioiodine therapy, euthyroidism

P534 The outcome of radioiodine subclinical hyperthyroidism.

therapy

in

patient

with

S. S. Abdelrazek, F. Rogowski, P. Szumowski, A. Zonenberg, A. ParfieĔczyk, M. Szelachowska, A. Sawicka, A. Poplawska-Kita; Medical University of Bialystok, Bialystok, Poland. The aim of our study was to assess the effectiveness of radioiodine (I131) therapy on the achievement of euthyroidism, prevention of adverse effects on the cardiovascular and skeletal systems and prevents evolvement to overt hyperthyroidism.Materials and Methods: We treated 590 patients, aged 30-70 years; (84%) of the studied groups were female and (16%) male; 210 patient with multinodular goitre (MNG), and 280 patient with autonomous nodule (ATN). Qualification of these patients were based on clinical features, normal levels of serum fT3 and fT4, low levels of serum TSH and characteristic appearance on thyroid scans and ultrasound. Some of the patients were treated with antithyroid drugs for 6 to 24 months before I131 therapy (110 patients). Malignant changes were excluded in all nodules by fine needle aspiration biopsy. All the patients had serum TSH levels less than 0.1 mU/l and effective half-life measured by the use of T24 and T48 was more than 3 days at the time of treatment. The activity dose was calculated by the use of Marinelli’s formula and ranged between 200-600 MBq. The absorbed dose (Gy) for MNG ranged between 150 and 260, and for ATN: 200-300 and was proportional to thyroid volume. Follow up control was done every 6 weeks. Repeated radioiodine therapy was given after 6 months of the first dose if indicated. Results: In general the success of treatment was: 99% of patient with ATN and 92% of patient with MNG achieved euthyroidism. 1% of patient with ATN and 7% of patient with MNG develop hypothyroidism. In all of the patients the symptoms and signs of subclinical hyperthyroidism disappeared (palpitation, tachycardia, atrial fibrillation, exercise tolerance improved, the blood pressure normalised and the quality of life improved). 1% of the patients had persistent or relapse of hyperthyroidism and received 2nd dose of radioiodine.Conclusions: Our results are good and are in the range of the existing literature in this field. The achievement of euthyroidism and the remission of the symptoms and signs of subclinical hyperthyroidism, were due to good diagnosis, well preparation of the patients; accurate measurement of administered activity, relatively high effective half-life, and wellorganised follow up. We recommend more aggressive treatment of these patients, and follow up visit in our department after 5 and 10 years of therapy to evaluate the long term effect of I131 therapy. Key Words: Multinodular goitre, autonomous nodule, radioiodine therapy, subclinical hyperthyroidism

P535 131-i therapy in hyperthyroidism radeva m*, shinkov a, borissova a-m , kovatcheva r, ivanova r, sarafova a, vlahov j M. A. R. Radeva; Clinical Center of Endocrinology,Sofia,Bulgaria, Sofia, Bulgaria. Radioiodine therapy is a well-established method for the treatment of patients with various forms of hyperthyroidism, preferred in many countries as first line therapy. Traditionally it has been applied in Bulgaria in low doses and in elderly patients with contraindications for surgery, and after long-term (sometimes more than 10 years) antithyroid drug administration. No systematic follow up of these patients has ever been done in the country. The aim of the current work was to assess objectively the results of radioiodine therapy and to set the foundations for an evidencebased treatment algorithm. 525 patients have been included into the study, of them 431 females, mean age 65.29 years and 95 males, mean age 59.52 years. Diffuse toxic goitre was found in 195 subjects and toxic nodular goitre was the diagnosis in 330 subjects . Doses between 3 and 10 mCi were applied depending on diagnosis, thyroid volume, patient general health etc. The subjects were followed at months 6, 12, 18 and 24 by TSH assay and thyroid 131-I uptake at 2, 4 and 24 h. 111 subjects presented for 6 month evaluation , 65 were followed at month 12. At both month

6 and 12 mean uptake values were significantly lower than baseline (all p<0.005). At month 6 25 (22.52%) subjects were hypothyroid (TSH>4.0) and 34 (30.63%) were euthyroid (TSH 0.34.0). AT month 12- 25 (38.46%) were hypothyroid and 22 (33.84%) were euthyroid. In conclusion, 131-I therapy is useful, economical and effective treatment dnd is more successful rherapy that surgery treatment. Further work is necessary to optimize the necessary dosis and thus decrease the persistent hyperthyroidism rate and the necessity for repeat doses.

P536 The role of radioiodine therapy in the treatment of patients with hyperthyroidism M. P. Yaneva, M. Marovska, A. Botushanova, A. Mihov, B. Popova, V. Stanchev; Clinic of Radiation Therapy and Nuclear Medicine, Medical University, Plovdiv, Bulgaria. Aim: Radioiodine treatment of hyperthyroidism is well known in the practice of the endocrinologists, but in the last years they have some fear to send patients for radionuclide treatment and try, sometimes for a very long time and unsuccessfully to treat them with antithyroid drugs.Moreover older patients have some contraindications for operative treatment. We aim to establish the efficacy of treatment with 131-I for older hyperthyroid patients. Material and method: 85 patients with hyperthyroidism, 67 women and 18 men at median age 67 ± 7,5. All of them were treated with thyreostatics for 3-5 years with data of relapse.The hormonal tests showed higher values than normal, they did not accept operative treatment and their possibility for treatment remained 131-I.The applied doses of 131-I were 5-6 mCi ( 188-200 MBq).The patients were treated as outpatients for the clinic. Results: After a follow up on the third and sixth month 57% (48 pts) did not need treatment, 42 % (36 pts) still accepted Laevothyroxin, but in a lower dosage and only 1 patient had no effect after the application of 131-I.Patients that did not respond to the first dosage of 5 mCi got another 5 mCi on the next year.Then the response was good and they had no need of thyrostatics.Our results show favourable influence of 131-treatment on hyperthyroidism.Patients felt much better after the iodine treatment and they had no unpleasant feeling during their stay in the Clinic. Conclusion: We strongly suggest that 131-I therapy should be applied to patients who had undergone unsuccessful treatment with thyreostatics, those that have relapse after operation and contraindications or unwillingness for operative treatment.

P537 Functional autonomies of thyroid and efficacy of radioiodine therapy O. Kraft1, A. Stepien2; 1Dept. of Nuclear Medicine, University Hospital, Ostrava-Poruba, Czech Republic, 2Dept. of Nuclear Medicine, 5th Clinical Military Hospital, Cracow, Poland. Aim Aim of this study was to establish the efficacy and determine the adverse effects of radioiodine therapy of patients with thyroid functional autonomies. Material and methods 799 patients (with age from 33 to 86 years; average age 58.7 years; the female:male ration was 7.4:1) with unifocal functional autonomy, multifocal functional autonomy and disseminated functional autonomy received at least one treatment of radioiodine. For diagnostics and the evaluation of radioiodine therapeutic effect of functional autonomies a thyroid scintigraphy is the basic and necessary procedure. We have also performed an thyroid ultrasonography, an assessment of a serum level of a total and free thyroxine, total triiodothyronine, TSH, radioiodine accumulation test, estimation of radioiodine effective half-life, in some patients TRH-TSH test. The follow-up examinations were done in all patients after 4-6 months, another examination after one year in 545 patients and after two years in 254 patients. One therapeutic dose received 733 patients (91,74%) and it was sufficient for an elimination of functional autonomies. Some patients were re-treated if there was the evidence of small or no treatment effect and no elimination of functional autonomies. 62 patients (7,76%) received two radioiodine treatments and 4 patients (0,5%) three treatments. Results Before radioiodine therapy an average serum levels of total thyroxine was 164.6 nmol/l, free thyroxine 20.8 pmol/l and total triiodothyronine 3.2 nmol/l, in all patients TSH was suppressed. Before therapy patients complaints were cardiovascular in 88% of patients, neurological in 72% of patients, hypermetabolic in 68% of patients and local in 30% of patients. After therapy the average serum levels of total thyroxine was 108.8 nmol/l, free thyroxine 12.5 pmol/l and total triiodothyronine 2.0 nmol/l and improvement of symptoms in 91%, without improvement in 8,7% and worsening in 0,3% of patients. The suppression of TSH disappeared in 607 of treated patients (76%). An average volume reduction of thyroid of 38% was achieved in any type of functional autonomy after radioiodine treatment. Side effects were minimal and in some patients presented as a transient neck pressure or pain and neck swelling as a manifestation of postradiation thyroiditis. Postradiation hypothyroidism was diagnosed in 36 patients (4.5%). Conclusion. The results of this study show that the radioiodine therapy of the thyroid functional autonomies is safe, with low incidence of adverse effects. It is effective, with high success rates and for patients non demanding and comfortable, it removes the cause of the disease.

P538 Effect of high dose radioactive iodine ablation on parathyroid gland function in thyroidectomized thyroid cancer patients with normal parathyroid gland function B. Ahn, J. Lee; Kyungpook National University, Daegu, Republic of Korea. Purpose: Radioactive iodine therapy (RIT) is widely used as a treatment of differentiated thyroid cancer and hyperthyroidism. Radioactive iodine rarely secretes into the parathyroid gland but it seems that radiation exposure of the parathyroid is significant due to its anatomical location close to the thyroid. There are few reports about change of parathyroid gland function by RIT in hyperthyroid patients, but no report about change of parathyroid gland function by Radioiodine ablation of remnant thyroid tissue. In our study we evaluate the effect of high-dose RIT(HDRIT) on parathyroid function in thyroidectomized thyroid cancer patients.Methods: 52 differentiated thyroid cancer patients (10 males, mean age 44.2±15.6 years) following near total thyroidectomy are included. Patients underwent repeated parathyroid function tests 1 week (6.2±1.2 days) and 12 months (11.8±4.7 months) after HDRIT. Parathyroid functions tests included serum levels of

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Poster Presentation

P533

calcium (Ca), phosphorus (P) and parathyroid hormone (PTH). We compared serum levels of Ca, P, PTH before RIT(Ca-1, P-1, PTH-1), those 1 week after HDRIT(Ca-2, P-2, PTH-2) with those 12 months after HDRIT(Ca-3, P-3, PTH-3) respectively.Results: Parathyroid function tests before HDRIT were all normal. Serum levels of Ca were 8.99±0.44 (Ca-1), 9.21±0.46 (Ca-2), and 9.16±0.57(Ca-3). Serum levels of P were 3.41±0.56(P-1), 3.68±0.43 (P-2), and 3.60±0.56 (P3). Serum levels of PTH were 31.43±13.66 (PTH-1), 30.03±12.12 (PTH-2), and 37.39±15.32 (PTH-3) respectively. There were no significant differences in serum levels of Ca, P and PTH with time. In only one patient PTH-2 was decreased but normalized thereafter.Conclusions: There were no significant differences in functional status of parathyroid gland between before and after HDRIT in differentiated thyroid cancer patients . In only one patient, PTH-2 was transiently decreased but normalized thereafter. We conclude that the effect of HDRIT on parathyroid gland is negligible.

P539 The outcome of patients with relapsed or refractory Graves’ disease and hyperfunctioning uni- or multinodular goiter after a personalized dose of Iodine-131 L. Florimonte1, I. Butti1, L. Pagani1, C. Di Leo1, L. S. Maffioli2; 1Ospedale di Lecco, Lecco, Italy, 2Ospedale Civile di Legnano, Legnano, Italy. INTRODUCTION Radioiodine therapy is the first-line treatment in relapsed or refractory Graves’ disease and hyperfunctioning uni- or multinodular goiter, The aim of the study was to determine the efficacy of a personalized dosimetric approach in order to treat Graves’ disease (GD) and uni- or multi-nodular goiter (NG) with the achievement of hypothyroidism or euthyroidism, respectively, as soon as possible. METHODS A total of 55 patients (42 F; 13 M; age = 57±13.5 years, range 17-82) underwent radiometabolic treatment (July 2002 - September 2005), after dosimetric evaluation. Twenty seven of these were affected by NG and 28 by GD. If ongoing, treatment with methimazole was discontinued (28 pts.). Before radioiodine therapy, an accurate measurement of functioning mass of the thyroid was obtained using a Tc99mpertechnetate planar scan, collected 25± 5 minutes p.i.. Each lobe or nodule was approximated with an ellipsoid: its axes were calculated with a threshold technique. Target masses ranged from 5 to 120 g (24± 21g) in GD group and from 3 to 69 g (14± 13 g) in NG group. To determine patient-specific kinetic parameters (maximum uptake and effective half life), I-131 thyroid planar images were acquired 6, 24 and >95 hours after oral administration of 1.5 ± 0.5 MBq of the radioalogen. All patients were followed up by clinical and biochemical (TSH) assessments at 1, 3, 6 months and each 6-8 months. RESULTS GD pts received 100-225 Gy, mean 165 Gy, (I-131 activity = 107-706 MBq, mean 377 MBq); NG pts received 120-235 Gy, mean 195 Gy (I-131 activity =107-666 MBq, mean 368 MBq). The follow-up period ranged from 6 to 45 months (median=16.9) in GD group and from 6 to 40 months (median=21.15) in NG group. In GD group TSH normalization was obtained in 92 days and the hypothyroid state was achieved 8.61 months after treatment in 23/28 pts (82%). In NG group TSH normalization was obtained in 94 days in 26/27 pts (96%) and the euthyroid state was maintained during the follow-up period. Six pts (1 in NG group and 5 in GD group) didn’t respond to the initial radioiodine dose. Four of them repeated treatment within one year, achieving stable hypothyroidism (follow-up= 3-27.37 months): in 2 cases surgical thyroidectomy was performed. CONCLUSIONS These data (better than those reported in literature for fixed activity) strongly support the adoption of a personalized dose estimation before to treat patients with hyperthyroidism.

P540 Twenty years of radioiodine therapy of hyperthyroidism O. Kraft1, A. Stepien2; 1Dept. of Nuclear Medicine, University Hospital, Ostrava-Poruba, Czech Republic, 2Dept. of Nuclear Medicine, 5th Clinical Military Hospital, Cracow, Poland. Aim Aim of this study was to evaluate results of hyperthyroidism therapy by radioiodine from 1986 to 2005. Material and methods 2198 patients (with age from 16 to 79 years; average age 54.2 years; only 11% of them were males) with hyperthyroidism [in 528 pts -24% hyperthyreoidism with functional autonomies (FA) - unifocal, multifocal or disseminated FA, in 30.4 % hyperthyreoidism with diffuse goiter, in 21.3% with normal thyroid, in 13.7% with nodular goiter, in 9.1% hyperthyroidism relapse after thyroidectomy, in 1.5% hyperthyroidism with retrosternal goiter] were treated by radioiodine. For diagnostics and the evaluation of radioiodine therapeutic effect of hyperthyroidism a thyroid ultrasonography and scintigraphy, an assessment of a serum level of a total and free thyroxine, total triiodothyronine, TSH, radioiodine accumulation test, and estimation of radioiodine effective half-life were done. Calculation of radioiodine amount is based on the formula in which the thyroid volume, radioiodine accumulation, effective half-life and absorbed dose (gray per gram) are. Normally absorbed dose was 80 Gy/g, in the case of complications (especially cardiac) 120 or 160 Gy/g, in FA 300-500 Gy/g. Results In total amount of 1670 pts with hyperthyroidism without FA after one-shot treatment the normal thyroid function was reached in 718 pts (43%), after the second therapy in 254 pts (15.2%), after three or more therapies in 147 pts (8.8%). Hypothyroidism after therapy developed in 488 pts (29.2%; in 19.1% early hypothyreoidism and in 10.1% late hypothyroidism). 63 pts (3.8%) had only transitory hypofunction. From 528 pts with FA one therapeutic dose received 468 patients (88.7%) and it was sufficient for an elimination of FA. Some patients were re-treated if there was the evidence of small or no treatment effect and no elimination of FA. 52 patients (9.8%) received two radioiodine treatments and 8 patients (1.5%) three treatments. In FA postradiation hypothyroidism was diagnosed in 22 patients (4.2%). Side effects were minimal and in some patients presented as a transient neck pressure or pain and neck swelling as a manifestation of postradiation thyroiditis. Conclusion. The results of this study show that the radioiodine therapy of hyperthyroidism after rigorous consideration of indication enables the effective treatment way and the most serious risk of treatment - postradiation hypothyroidism - forms substantially less grave condition than inefficiently treated hyperthyroidism.

S334

P541 The effect of second dose 131I in patients with hyperthyroidism, being treated by 185MBq low fixed dose regimen P. H. Bochev, K. Hristozov, A. Klisarova, B. Chaushev; Medical University, Varna, Bulgaria. Radioiodine treatment is a well known and widely exploited treatment modality in patients with Graves disease. Although there are controversies regarding the initial dose regimen and its estimation, lower doses are associated with lower incidence of postterapeutic hypothyroidism, but with higher relapse rate too. In these cases a second dose is needed to achieve therapeutic effect. We aimed to estimate the success rate of the second dose 131I in patients, treated with low initial dose 185MBq 131I. The initial low dose regimen was based on legislation restrictions for outpatient base treatment with radioiodine. Subject to our study were 14 patients with Graves disease treated with 185MBq 131I who were still hyperthyroid six months after the initial treatment. All the patients were followed up for at least one year after the last therapeutic dose 131I administered. Based on the serum levels of thyroid hormones,TSH and reduction of gland size a decision for repeating the dose was taken in 8 patients. The other 6 patients were treated with antithyroid drugs until the first year after the administration of radioiodine. By now only 12.5% of the treated with second dose are still hyperthyroid, 37.5% are euthyroid and 50% are hypothyroid resulting in 87% overall success rate of the treatment (hypo+euthiroid). Contrary only 16% of the treated with ATD showed normalization of the thyroid status for the same period of follow up. In conclusion we can recommend early repeat of the treatment with a second dose 131I if the patient is still hyperthyroid at the sixth month after the initial treatment with low dose regimen.

P43 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Radionucl.Therapy/Dosimetry - Clinical: Thyroid, Bone Pain Palliation & Miscellaneous 3 P542 Changes of thyroid hormone values during radioiodine therapy G. Kirsch, A. Zinke, M. Trautmann, C. Wisotzki, U. Bohl, M. Luhn; Department of Nuclearmedicine, Greifswald, Germany. Aim: During radioiodine therapy (RIT) changes of thyroid hormones may occur, sometimes exacerbation of hyperthyroidism. In literature acute hormone changes are described differently. Guidelines recommend in hyperthyroid patients antithyroid pretreatment and withdrawal of thionamides 2-3 days before RIT. Studies under these conditions are rare. We determined thyroid hormones before and 4 days after I-131 application. Results of RIT patients with different premedication regimes are reported.Methods: Out of a thyroid database 2799 RIT patients (immunogenic and nonimmunogenic hyperthyroidism, euthyroid goiters, RIT 1995-2005) were selected who had hormone values directly before (baseline) and 4 days after RI application. They were grouped related to the withdrawal time of medication before RIT. Thionamides (MMI) were cancelled (MMI off ) 4 weeks, 1 week, 3 days or not at all before RIT. In patients with pronounced hyperthyroid baseline values MMI medication was restarted 2-3 days after RI applikation (MMI on).Results: Regarding all patients fT4 increased significantly 10% 4 days after RIT from baseline values of 21,5 pmol/l; in group ‘MMI on’ 9% (baseline 21,1 pmol/l, n=234), in group ‘MMI off at least 4 weeks’ 10% (baseline 19,6, n=1073), in group ‘MMI off 1 week’ 14% (baseline 21,6, n=824), in group ‘MMI off 3d’ 25% (baseline 20,6, n=128), in group ‘MMI off 3d, again on at 3.d’ 11% (baseline 29,9, n=45) and in group ‘T4 on 2 weeks before/during RIT’ 4% (baseline 32,7, n=495). Related to the fT4 increase was a decrease of TSH of about 30% (baseline values 0,06-0,31 mU/l). Tg rose about 100% (baseline 58 ng/ml, n=58). There were minimal changes in T3, TPO-AB and TSHR-AB and no significant correlation between thyroid hormone changes and absorbed RI dose. In 31 patients (1,1%) high fT4 values over 50 nmol/l were recorded; among them 6 over 70 nmol/l (1 thyroid storm).Conclusions: Acute thyroid hormone changes during RIT are in general mild (fT4 elevation of about 10% over baseline). In 1% RIT leads to excessive high fT4 values after antithyroid medication is cancelled for a short period.

P543 Radioiodine treatment in patients with hyperthyroidism in a mild iodine deficiency area H. Demir1, Y. Z. Tan1, S. Isgoren1, F. Berk1, I. Tarkun2, Z. Canturk2, B. Cetinarslan2; 1Kocaeli University School of Medicine Department of Nuclear Medicine, Kocaeli, Turkey, 2Kocaeli University School of Medicine Department of Internal Medicine, Kocaeli, Turkey. Aim: Radioiodine is used successfully since more than 50 years for treatment of hyperthyroidism. The purpose of this retrospective study was to evaluate success and complication rate of radioiodine treatment in patients with hyperthyroidism, in an area with mild iodine deficiency and represent our results.Materials and Methods: One-hundred seventy nine patients (62 male, 117 female, mean age 55.4) were treated with radioiodine between the years 2002-2005. However 126 of them could be followed after therapy. Patients were categorized into three diagnostic groups: Graves' disease (GD) (n:27), solitary toxic adenoma (TA) (n:86), and toxic multinodular goitre (TMG) (n:66 ). According to I-131 uptake test, thyroid function test results, thyroid and nodule dimensions in ultrasonography, patients were treated with a 370-1110 MBq (10-30 mCi) I-131.Results: The largest group was TA (%48.4), followed by TMG (%35.7) and GD (%15.9). Mean duration of follow-up was 10.7 months (range 1-32). Either hypothyroidism or euthyroidism were considered cure. At the end of the follow-up period, a total of 102 patients (81.0%) were treated successfully. The rates of cure for GD, TA, and TMG

P544 Radioiodine treatment of Graves' approximation dosimetry method

disease

by

first

M. Zingrillo1, N. Urbano2, A. Venetucci2, S. Modini2; 1Endocrinology Unit, Centro di Riferimento Oncologico della Basilicata, Rionero in Vulture, Italy, 2 Nuclear Medicine Unit, Centro di Riferimento Oncologico della Basilicata, Rionero in Vulture, Italy. Aim: to assess the efficacy of radioiodine doses between 5.5 and 7.4 MBq/mL enabling to give the thyroid tissue a radiation dose above 10.000 cGy, achieving prompt control of hyperthyroidism in the majority of cases with a single radioiodine dose.Materials and Methods: 69 patients affected by Graves’ disease were enrolled in the study. The inclusion criteria were: relapse after anti-thyroid drugs (ATD) suspension, contraindications (liver disease) and side effects (leukopenia) after ATD. Patients with thyroid volume higher than 60 mL, suspected nodules and active ophtalmopathy were excluded. All the patients, who stopped ATD since 5 days (metimazole) and 15 days (propylthiouracil), underwent thyroid uptake test with 1.85 MBq of 131I and measurements on neck and thigh at 2, 6 and 24 hours after the ingestion of capsules. Thyroid volume was obtained by ultrasonography (US) and calculated by ellipsoid method. Mean thyroid volume was 28.8±13.6 mL (range 8.8-59 mL). First approximation dosimetry took into account thyroid volume and 24 hrs uptake percentage with the following formula: (5.5 MBq * Thyroid volume (mL))/(24 hrs uptake * 10). A dose of 7.4 MBq/g was used in some cases where a rapid and final effect was preferable, such as in difficult patient management due to logistic reasons or character disorders. Immediately after 24 hrs uptake measurement, radioiodine dose was calculated, prepared and administered to the patients, even to prevent iodine pollution with subsequent ineffectiveness of treatment. Mean administered dose per volume unit was 4.2±1.4 MBq. ATDs were administered again only in selected cases (strong hyperthyroidism) and never before 7 days. The patients had a mean follow-up of 24 ± 14 months (range 1 60).Results: 53 patients were successfully treated by one dose, 12 patients by two doses and 1 patient by three doses. 3 patients are actually under observation after the first dose of radioiodine. In the group treated by one dose, 17 pats. were euthyroid, 29 hypothyroid and 7 subclinically hyperthyroid. In the group treated by two doses, 3 pats. were euthyroid, 8 ipothyroid and 1 had subclinical hyperthyroidism. The patient treated by three doses was in hypothyroidism. Overall efficacy of treatment was therefore 84%. The mean reduction of thyroid volume after therapy was 61±19 %. Three patients had a significant worsening of ophtalmopathy, in two of them it decreased after steroid treatment.Conclusions: Our experience underlines that a successful dose individualization can be achieved with modest commitment of resources.

P545 Radionuclide therapy with samarium-oxabiphore, painful bone metastases

153

Sm for

V. V. Krylov, A. F. Tsyb, B. Y. Drozdovsky; Medical Radiological Research Center of RAMS, Obninsk, Russian Federation. Aim Our aim was to study the potentialities of Samarium-Oxabiphore,153Sm in therapy of patients with painful bone metastases as well as to evaluate the clinical efficacy and the quality of life. Materials and Methods We have treated 118 breast cancer patients, 76 prostate cancer patients, 17 thyroid cancer patients and 26 lung carcinoma patients with painful bone metastases. All the patients received radiation therapy, chemotherapy and hormonal therapy before. Patients with thyroid cancer were given radioiodine therapy. However, pain syndrome and progression of bone metastases persisted. Samarium-Oxabiphore,153Sm was injected intravenously at 1 mCi (37 MBq)/1 kg body weight. Pain intensity was measured on a 10-point scale for 3 months, and the quality of life was evaluated according to the Karnofsky scale. Results Bone pain usually began to reduce at 5-10 days after the application of Samarium-Oxabiphore,153Sm. Pain syndrome (pain index in points) had the following dynamics: In breast cancer patients: before therapy - 5,98 points, at 1 month after application - 2,88 points, at 3 month after application - 3,24 points. In prostate cancer patients: before therapy - 5,75 points, at 1 month after application - 3,54 points, at 3 month after application - 4,08 points. In thyroid cancer patients: before therapy - 5,65 points, at 1 month after application - 3,05 points, at 3 month after application - 3,25 points. In lung carcinoma patients: before therapy - 7,75 points, at 1 month after application - 5,85 points, at 3 month after application - 6,15 points. In response to therapy, the Karnofsky index was as follows: In patients with breast cancer - 64,2% before therapy, 72,1% at 1 month, 68,7% at 3 months; in patients with prostate cancer - 63,4% before therapy, 71,7% at 1 month, 68,4% at 3 months; in patients with thyroid cancer - 62,9% before therapy, 70,2 % at 1 month, 67,9% at 3 months; in patients with lung carcinoma - 52,2% before therapy, 55,6% at 1 month, 54,2% at 3 months. Conclusion Therapy with Samarium-Oxabiphore,153Sm appears to be effective for pain relief and improvement of the life quality in patients with painful bone metastases.

P546 Sm-153-EDTMP Recurrencies?

for

Therapy

of

Hypernephroma

H. F. Sinzinger1, B. Palumbo2, H. Ahmazadehfar1, S. Granegger1, R. Palumbo2, J. Hiltunen1; 1Medical University Vienna, Vienna, Austria, 2 University of Perugia, Perugia, Italy.

increased uptake in at least one of the lesions could be seen in conventional bone scintigraphy. Patients were treated using the Vienna protocol with repeated 30 mCi Sm-153-EDTMP intravenously. Data from the first of a series of treatments are reported. Whole body retention ranged from 34 to 77 % (mean 52,2%). Two patients (5,1 %) showed a flare phenomenon on days 3 - 8 and 4 - 10, respectively. Conventional bone scintigraphy and posttherapeutic Sm-153EDTMP scans revealed identical findings in all the patients. 20 patients (51,3 %) exhibited complete pain relief, lasting in 17 of them up to the next scheduled therapy after 3 months. 15 patients (38,5 %) showed a partial response, while 4 patients (10,3 %) had none. Haematological control at 3 and 6 weeks (platelets [-27 and -19%], white [-23 and -25%] and red blood cells [-11 and -21%]) showed a small but always reversible decline. Adhesion molecules have been implicated in tumor progression and metastasis. One single Sm-153-EDTMP treatment decreased ICAM-1 (869,3 to 739,5 ng/ml; p<0,01), VCAM (128,6 to 84,4 ng/ml; p<0,01) and E-selectin (342,8 to 296,9 ng/ml; p<0,01). Interassay variation was 5,5 ±; 1,7, 4,9 ±; 1,2 and 5,2 ±; 1,5, respectively, intraassay variation 2,5 ±; 0,6, 2,8 ±; 0,7 and 2,4 ±; 0,5, respectively. Whether this decrease is associated with lesion regression still needs to be assessed after a longer follow-up period. Basic data and therapeutic response therefore seem not to be significantly different between osteoblastic and osteoclastic lesions. These findings indicate that even in osteoclastic recurrences in hypernephroma as long as areas with increased bone uptake in conventional scintigraphy can be detected, Sm-153-EDTMP is still a promising therapeutic option.

P547 Radionuclide therapy with 153Sm-Lexidronam combined with Chemotherapy in patients with hormone-refractory prostate cancer (HRPC): first results U. Nestle1, J. Lehmann2, S. Bock1, G. Farmakis1, M. Stoeckle2, C. M. Kirsch1; 1Dpt. of Nuclear Medicine, Saarland University Medical Center, Homburg/Saar, Germany, 2Dpt. of Urology, Saarland University Medical Center, Homburg/Saar, Germany. Aim: Radionuclide therapy is well established for palliative treatment of bone metastases from prostate cancer. In recent years, systemic chemotherapy has also achieved an important role for the treatment of hormone refractory cases (HRPC). In a first group of clinical cases, we have combined both therapies in a newly established protocol. Here, we report preliminary data on toxicity and PSA-response of this combination.Materials and Methods: In 2005, we treated 10 patients for bone metastases of HRPC with 37 MBq/kg BW 153Sm-lexidronam. Five of these patients, for individual clinical reasons, received 2 - 7 weekly doses of chemotherapy simultaneously with 35 mg Docetaxel per m2. In these cases, the radionuclide was given one day before the second dose of chemotherapy. Toxicity and PSA response was evaluated for all patients.Results: In one patient receiving radionuclide therapy alone, PSA declined by 22 % from the initial value lasting for 8 months after treatment. Another patient maintained a stable PSA value for 4 weeks post treatment. In the other cases, no PSA-effect was observed. After combined treatment, two cases showed a marked decrease of PSA, by 80% and 74% from the pre-treatment value lasting for 2 and 4 months, respectively. In one case, a stable PSA value was confirmed for 5 months, in 3 cases, no PSA decrease was observed. After radionuclide therapy alone, the maximum hematologic toxicity was grade III in 2 cases (minimum hemoglobin 7,0 109/l 5 weeks after radionuclide, and minimum thrombocytes 39000 109/l 1 week after radionuclide). After combined therapy, grade III hematologic toxicity was observed in two cases as well (minimum hemoglobin 7,5 109/l each, 4 and 6 weeks after radionuclide treatment, respectively). No other toxicity was seen in both treatment groups.Conclusions: Our preliminary data show a promising efficacy of the combined treatment with a PSA-response > 50% in 2/5 cases, which could not be observed in any patient after radionuclide therapy alone. The toxicity after combined treatment was moderate and comparable to that after radionuclide therapy alone.

P548 Bone metastasis Radiotherapy

from

solid

tumors:

153

Samarium

M. Catalano, M. L. De Rimini, P. Muto; Nuclear Medicine AORN Monaldi, Naples, Italy. Objectives: to test advantages and efficacy of sistemic metabolic radiotherapy with 153 Samarium in treating patient’s bone pain due to metastasis from breast, lung, prostate and other solid tumors and to evaluate hematological tossicity and its reversibility.Methods: We studied 70 pts with intermittent or persistent, mild, moderate and severe bone pain with complications adversily affecting patient’s life quality. All patients (pts) enrolled in this study had skeletal osteoblastic methastasis ranging from < 10/>10 hot spots at bone scan. Pts with a white blood cell count of less than 2.600/ L and platelet count of less than 100.000/L were excluded. After treatment we followed the pts every week for at least twelve weeks by two kind of questionnaire reguarding life quality and bone pain intensity. Hematological tossicity was tested after the first and the second month after treatment.Results: 153 Samarium was able to palliate bone pain from bone metastatis in 56 pts (80%) and 5 of them with complete pain relief. In the last 14 pts the therapy failed because no change in pain intensity or in analgesic posology was observed. In some pts there was worsening of pain and performance status because of ill progression (skeletal methastasis or other apparatus involvement). There was no correlation between number of bone methastasis, pain severity and therapy efficacy. We had no adverse events, in only 5 pts transient “flare fenomenon”, and generally mild and transient myelosuppressive effects were observed generally after three weeks with a complete recovery by eight weeks after treatment.Conclusions: Our preliminary data suggest that bone pain radiotherapy with 153 Samarium is simple to admnister on an out-patient basis, highly effective in a large number of pts both with advanced cancer both in the earlier phase of illness when they are still asymptomatic but with bone scan evidence of methastasis. Mild transient myelosuppressive effects and no adverse side effects observed in the majority of the pts studied, suggest safety of systemic metabolic radiotherapy. We hope to expande our clinical experience about efficacy of retreatment, because actually only 5 pts had received the second dose of 153 Samarium and about the efficacy in reducing bone metastasis size that we observed in only one patient who underwent chemiotherapy too.

Sm-153-EDTMP has been shown effective for pain relief, lesion stabilization / regression and tumor marker / indicator response in osteoblastic recurrences. Consistent data for osteoclastic recurrences, however, are not available. We were examining the effect of Sm-153-EDTMP on pain response in 39 patients (24 m, 15 f, 54 - 76 years) with proven bone recurrences if an

S335

Poster Presentation

groups were 17 (85%), 48 (78.7%) and 37 (82.2%), respectively. There was no significant difference in the cure rate between any groups (p > 0.05). The incidence of hypothyroidism did not vary significantly between any groups (p > 0.05). There was no significant complication after treatments. Three patients were given second radioiodine doses because of ineffective treatment. After second doses those patients had become hypothyroid.Conclusions: The treatment success in subgroups did not differ significantly. Our overall cure rate was concordant with previous studies although our patients were living in a mild iodine deficiency area. Radioiodine treatment sufficiently and safely eliminated hyperthyroidism of our patients.

P549 Radionuclide and drug therapy of bone lesions D. Metchev1, M. Firsova1, N. Polyakova2, M. Krushinsky2; Ukraine, 2Kyiv City Oncology Hospital, Kyiv, Ukraine.

1

KMAPO, Kyiv,

Table of Contents Aim: to exam the efficiency of application of new approaches for treatment painful bone lesions in oncology patients.Materials and Methods: it has been applied combined radionuclide (89Sr-chloride) and drug (hormones, amifostin, bisphosponates, xeloda) systemic therapy in 133 patients (182 episodes) with bone lesions of breast cancer (86), prostata cancer (39) and multiple mieloma (8). Treatment efficiency was evaluated using Karnofski scale, laboratory( blood count, blood calcium) and radiological ( RIA, radiography, osteoscintigraphy, MRI) methods.Results: Combined radionuclide and drug systemic therapy has been shown to be the most effective scheme. It has provided 96,8% of the “comfort” life (Karnofski index-60-80) during the first year of treatment (against 78,7% for single 89Sr- chloride therapy). It is also noted that this scheme would inhibit bone lesions development, stabilize existing changed and promote topical osteosclerosis in some cases. After analyzing the results of treatment, authors recommend special protocol for 9-10 monthes treatment: 89Sr-chloride (150 MBq) with amifostin, like a citoprotector (first part of treatment) and multimodelity drug therapy (second part) hormonotherapy ( femara or zoladex - breast cancer, casodex, fosfestrole or flutamid -prostata cancer), bisphosphonates (bonefos and zometa-breast, prostata, multiple mieloma) and chemotherapy with xeloda.Conclusions: the experience of clinical usage of the 89Sr-chloride with supportive drug therapy has received positive estimation and confirms the efficiency of this method of treatment: -improves quality of life in patients with multiple lesions in bones;-refuses the narcotic analgesia consumption;-delays the development of new pain sites;-eliminates necessity of radiotherapy in indicated periods of observation;-prolongs the period of remission.

P550 Effectivnes of therapeutic doses of Re-186 HEDP, Sr-89 and Sm-153 EDTMP in painful osseaus metastases. E. M. Trivizaki, A. T. Georgakopoulos, L. A. Iordanidou, S. A. Saranti, K. N. Rethimniotakis, M. A. Kokkinovrahou, P. T. Koutsiouba; Metaxa’s Memorial Cancer Hospital, Piraeus, Greece. The aim of this study was to determine the response rate of radionuclide therapy using Re-186, Sr-89 and Sm-153 in different ongological pts with bone metastases. Method : Eighty six patients (44 males, 42 females with age range between 40 and 85 years), 32 with breast cancer, 20 with cancer of prostate, 6 with lung cancer and 19 with other tumours (3 bladder, 3 colon, 2 renal, 4 uterus, 2 osteosarcomas and others), were investigated for the effectivness of Re-186 HEDP (64 pts), of Sr-89 (16 pts) and of Sm-153 (6 pts). A separate questionary was recorded for every patient and among others the most important question was the degree and the duration of pain in different intervals. On the basis of the grade of the pain relief, the pts were divided in four classes. Class I pain with not distictictive changes. Class II mild decrease of pain. Class III significant relief of pain . Class IV pain free. We also separated two groups. Group I (number of metastases >10, 66 pts) and Group II (number of metastases <5, 20 pts). In 10 pts succesive treatment (16 doses) was followed. We kept records at weekly intervals for the first month and every two weeks for the next two months. Results : The overal response rate in pts with breast cancer was 75 %, in pts with prostatic cancer was 83 %, in pts with lung cancer was 66 % and in all the other tumours, the pain response observed was only 16 %. On the basis of pain relief we had .

Aim:The management of pain in patients with bone metastases is a real clinical problem.One of treatment modalities is 153 Sm therapy.153 Sm is classified as agent which controls both:pain and dissease itself.Its application is designed mainly for treatment of bone metastatic breast cancer patients.This study is aimed for estimation of prognostic value of tumor and bone turnover markers in follow up of 153 Sm therapy.Materials and Methods: 32 breast cancer patients with scintigraphically confirmed multiple bone metastases were the subject of this study.Patients reported pain relief according to 1-10 scale.0 for no pain relief,10 for no pain.For serial measurement of markers after 3 month 15 patients were available.All patients were treated with bisphosphonates.Waste specimens of sera from patients were collected after they served their diagnostic and clinical purposes.Sera were collected before 153Sm injection(baseline) and 3 month later.CA 15-3 was assayed with AXSYM by Abbott,CEA with AutoDelfia by Wallac,Bone TRAP with EIA by IDS ,PINP and ICTP with RIA by Orion.Statistics: correlation Pearson test and t-test.Results:9/32 patients reported no relief or weak pain relief(0-4)average 1,55.23/32 patients reported significant pain relief(5-10)average 7,5.There were no statistical differences between the groups with weak response versus significant pain relief in concentrations CA 15-3,CEA,TRAP,PINP,ICTP at baseline. There were no statistical differences between baseline concentrations of any marker and 3 month later for both groups.There were significant differences above least significant change(LSC) between baseline value and after 3 month for individual patients but their direction is independent of pain relief .Conclusions:Pretreatment concentrations of tumor and bone turnover markers have no prognostic value for efficacy of 153Sm treatment of pain. 153 Sm therapy has no influence on progression of disease as measured with tumor and bone turnover markers.

P552 Prognosric value of serum tumor and bone metabolizm markers in follow up of 89Sr treatment for painful bone metastasis in prostate cancer patients M. Konieczna1, A. Koáodziejczyk2, J. ĩebrowski2, E. Dziuk1; 1Military Medical Institute, Warsaw, Poland, 2Military Clinical Hospital, Wrocáaw, Poland. Aim:Widely used method for treatment for pain in bone metastases in prostate cancer is 89Sr therapy. It is claimed that palliation is linked to dissease control as well.Aim of study is to estimateof correlation between concentration of PSA,CEA,TRAP,PINP,ICTP and pain relief after 89Sr injection and progress of dissease as measured with this markers.Materials and Methods:28 prostate cancer patients with scintigraphically confirmed multiple bone metastases were the subject of this study.Patients reported pain relief according to 1-10 scale.0 for no pain relief,10 for no pain.For serial measurement of markers after 1 month 21 patients were available..Waste specimens of sera from patients were collected after they served their diagnostic and clinical purposes.Sera were collected before 89Sr injection(baseline) and 1 month later.PSA and CEA were assayed with AutoDelfia by Wallac,Bone TRAP with EIA by IDS ,PINP and ICTP with RIA by Orion.Statistics: correlation Pearson test and t-test.Results:8/28 patients reported no relief or weak pain relief(0-4)average 1,88.20/28 patients reported significant pain relief(5-10)average 7,95.There were no statistical differences between the groups with weak response versus significant pain relief in concentrations PSA,CEA,TRAP,PINP,ICTP at baseline. There were no statistical differences between baseline concentrations of any marker and 1 month later for both groups.Significant differences above least significant change(LSC) between baseline value and after 1 month were found for individual patients but their direction(diminished,increased or stable) is independent of response on 89Sr treatment. .Conclusions:Baseline levels of tumor and bone metabolizm markers have no prognostic value for efficacy of 89Sr treatment of pain in prostate metastatic cancer. Progression of dissease monitored with tumor and bone metabolizm markers is independent of efficacy of 89Sr treatment for painful bone metastasis in prostate cancer.

Breast Cancer and Prostate Cancer

Re186 Sr-89

No

Class

Class

Class

Class

No

Class

Class

Class

Class

pts

I

II

III

IV

pts

I

II

III

IV

31

8

5

11

7

19

4

4

6

5

1

-

1

-

-

8

-

2

4

2

2

1

1

-

-

Sm153

The mean duration of the effectivness was 2,35 months (1-36 months). The hematological parameters were not affected after the administration of all radiopharmaceuticals. In pts of Group I with extensive bone disease, substantial improvement of pain syndrome with total diasappearance of pain, found in 4/66 and in Group II in 4/20. Overal therapeutic response for Group I was 65 % and for Group II was 80 %. Conclusion : All the radiopharmaceuticals used had comparable effects concerning the degree and the duration of pain relief. The repeated administrations are useful to control pain, but the degree of the pain relief diminishes in successive administrations. The treatment in pts with other types of tumours is considered not having so good response to treatment. Cases with less bone metastatic lessions are considered having better response.

P551 Tumor and bone turnover markers in breast cancer patients treated with 153 Sm for bone metastases:a preliminary report M. Konieczna1, A. Koáodziejczyk2, J. ĩebrowski2, E. Dziuk3; 1Military Medical Institute, Warsaw, Poland, 2military clinical hospital, Wrocáaw, Poland, 3Military Medical Iinstitute, Warsaw, Poland.

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P553 Yttrium-90 synovectomy in management of recurrent knee joint effusions B. E. Chrapko1, R. Zwolak2, R. GoáĊbiewska1, A. NocuĔ1, M. Majdan2; 1 Chair and Department of Nuclear Medicine, Skubiszewski Medical University of Lublin, Lublin, Poland, 2Chair and Clinic of Rheumatology and Connective Tissue Diseases, Skubiszewski Medical University of Lublin, Lublin, Poland. The aim of this study was to assess the effectiveness of radiation synovectomy (RSV) in treatment of recurrent joint effusions, using Y-90 in patients with chosen inflammatory joint diseases: rheumatoid arthritis (RA) and seronegative spondyloarthropaties (SPA). The group of treated patient included 39 persons (53 joint knee).Qualification for the treatment was based on: clinical assessment: subjective evaluation of pain, degree of effusion, three- phase bone scintigraphy (BS3) , biochemical analyses: concentration of C-reactive protein- CRP and fibrinogen. Intra- articular injection of 185 MBq of Y-90 was performed. Biochemical analysis was repeated after 48 hours, 4 and 24 weeks, whereas BS3 was repeated after 24 weeks. Changes in the second phase of BS3 were assessed visually, using four degrees scale and in the third phase- semiquantitatively with J/B ratio. During observation after RSV, the knee significant effusion reappeared only in 4 joints in patients with RA (9,4% of treated joints), whereas in SPA relapse was not observed. Obtained the following mean levels of CRP(mg/l): before RSV 37.3±44.7; after 48 hours 26.8±28.7, after 4 weeks-16.8±16.5, after 24 weeks- 18.5±16.2. The mean levels of fibrinogen (g/l) were respectively: 5.2±1.6; 4.4±1.9; 4.7±1.2; 4.7±1.6. CRP level 4 and 24 weeks after RSV was significantly lower then before the therapy, whereas fibrinogen values before and after RSV were not different. Changes in blood pool before RSV-3.6±0.6; after the therapy-2.09±0,8 (p<0,001). Changes in the third phase of BS3-J/B ratio- before RSV2.50±08, after treatment-2.19±0.9 (p<0,05). RSV makes an effective method to treat recurrent effusions in patients with RA and SPA.

P44 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

lower than in clinical situations. Therefore, extrapolation of the absorbed doses from preclinical to clinical situations must be performed with caution.

Radionuclide Therapy / Dosimetry: Data Collection Methods / Dosimetric Models / Pharmacokinetics

P557

Is lithium as adjunct to radioiodine therapy in patients with Graves` disease - useful or not? S. Dunkelmann, H. Künstner, B. Rohde, P. Groth, C. Schümichen; University of Rostock, Clinic of Nuclear Medicine, Rostock, Germany. Evaluation of intrathyroidal kinetics of radioiodine with and without lithium as adjunct with respect to the effect of lithium on the intrathyroidal half-life of radioiodine in patients with rapid turnover in the pretherapeutic diagnostic test. Methods: 171 patients with Graves` disease were included in three groups in the study. Group I with 140 patients served as control group, Group II with 19 patients and Group III with 12 patients were distinguished by an intrathyroidal half-life of radioiodine below 3 days in the diagnostic test. Patients in Group III received 885 mg lithium carbonate a day for two weeks as adjunct to radioiodine therapy. Both diagnostic and therapeutic radioiodine kinetics were followed up by at least 10 uptake measurements within a minimum of 48 hrs. Kinetics of radioiodine were defined mathematically as balance of the thyroidal iodine intake and excretion by a two-compartment model. In all groups, an occasional thyreostasis was discontinued 2 days before the diagnostic radioiodine test. Results: Under therapy, the maximum uptake of radioiodine was reduced by nearly 10 % in all groups, in Group I, the effective half-life as well as the product of maximum uptake x effective half-life as an equivalent of radiation dose independent of thyroid volume was lowered in the same magnitude. This is believed to be an early therapeutic effect of radioiodine, since thyreoglobulin increases shortly after radioiodine application. In Group II, the energy-dose equivalent remained constant under therapy, because of statistical reasons. In case of extreme (short) values of effective half-life it cannot be expected that these should occur again to this extent in a subsegment examination. With adjunct lithium in Group III, the effective half-life was prolonged by factor 2.18 ± 1.35 whereas the volumeindependent energy dose equivalent increased only by factor 1.36 ± 0.73 due to a reduced uptake under therapy. No severe side effects of lithium were observed. Conclusion: Using lithium as adjunct to radioiodine therapy increases the radiation dose delivered to the thyroid by 36 % on average and at least 25 % of radioiodine activity can be saved in these patients. Lithium is recommended in patients with very short effective half-life in the diagnostic test in order to reduce the activity required and whole-body radiation dose.

P555 Cellular dosimetry studies in cell clusters A. Oliveira, M. Neves; Instituto Tecnologico Nuclear, Sacavém, Portugal. The aim of this work is to develop an analytical algorithm suitable for computational implementation in cellular dosimetry based on the MIRD approach, allowing several degrees of freedom such as the number and position of cells, the number of cells contaminated and the modes of contamination. The user can apply the values of S-factor that he wants, allowing it to compare different values of S-factors and their importance for the cell cluster dose. As a first approach we will allow any kind of cell clusters, however, the model will be restricted to spherical cells. It is well known, assuming a given model of cell cluster and the MIRD scheme that the dose for the cell k due to the cumulative activity in the cell h it depends of the S-factor, S(cellkĸcellh). The S-factor is the mean dose per unit of cumulated activity in cell h. This leads to our basic definition: If the cell is the basic unit of live then a pair of cells is the basic unit of cellular dosimetry. This basic unit for cellular dosimetry is defined by a contaminated cell of radius Rc and a non-contaminated cell of radius Rnc with a given value, Ric, of the inter-cellular distance. From the literature it will be implemented a data base with self-doses and cross-doses of the basic unit of cell dosimetry. The absorbed dose to a cell cluster is obtained from all the basic unit of dosimetry that exists in the cluster. Applications to several cell clusters will be tested.

P556 Extrapolation of preclinical radionuclide therapy results to clinical situations - influence of photon irradiation H. Uusijärvi, P. Bernhardt, E. Forssell-Aronsson; Department of Radiation Physics, Göteborg University, Göteborg, Sweden. Aim: The evaluation of radionuclides for targeted therapy starts with preclinical studies in cell cultures and animal models, e.g. mice and rats. Various radionuclides, such as the Auger-electron emitters 111In, 125I and 67Ga, have shown promising preclinical results. However, these Augerelectron emitting radionuclides emit photons, which will irradiate the normal tissue in an undesirable way. In a human body the absorbed fraction of photons will be larger than in a mouse or a rat. Therefore, the risk of normal tissue toxicity in patients, e.g. bone marrow suppression, might be underestimated when relying on preclinical results. To illustrate the influence of photons on different body masses the ratio between the absorbed dose rate to the tumour and normal tissue (TND) was calculated for humans, rats and mice for the Auger-electron emitters: 111In, 125I and 67Ga; and the beta emitters: 90Y, 131I and 177Lu. Material and methods: The absorbed dose rate to spherical tumours of different sizes, ranging from 1 ng to 1 g, was divided by the absorbed dose rate to the whole body. The whole body of a human was simulated by a 70-kg ellipsoid, a rat by a 300-g ellipsoid and a mouse by a 20-g ellipsoid. The radionuclides were assumed to be uniformly distributed within the entire tumour and normal tissue. The activity concentration was assumed to be 25 times higher in the tumour compared to the normal tissue. Both the tumour and normal tissue were assumed to be of water density. Results: The TND values for 90Y did not differ between humans, rats and mice. For 177Lu the TND values differ less than 7.3% between the different species. 131I showed similar TND values for rats and mice, while the TND values were 1.6 times lower for humans. For 111In, 125I and 67 Ga, however, the TND values differed considerably between the different species. The TND values for humans compared to mice were 3.3, 2.0 and 2.1 times lower for 111In, 125I and 67Ga, respectively. Conclusions: In preclinical studies the influence of photons on the absorbed dose is

S. Chittenden, B. Pratt, K. Pomeroy, P. Black, C. Long, N. Smith, G. Flux; Royal Marsden NHS Foundation Trust, Sutton, United Kingdom. The importance of accurate measurements of whole body retention of patients during radionuclide therapy has now been widely recognised. These measurements provide essential information in three areas. Firstly they enable radiation protection advice to be given during and after therapy. Secondly they enable calculation of the whole body dose delivered during therapy which allows investigation of potential correlation of dose with treatment outcome. Thirdly the determination of delivered dose (either from a low activity ‘tracer’ administration or from previous therapies) allows treatment planning to be carried out for future radionuclide therapy on an individual patient basis. There are significant difficulties associated with taking wholebody retention measurements of children especially where they are very young and / or feeling unwell. It is obviously preferable to carry out measurements in a way that minimises disturbance to the child whilst still providing good quality data. To accomplish this we have recently installed a specially designed whole body dose monitoring system for these patients. Dose rate measurements were taken at specific distances from therapy and tracer patients at different activity levels. These were used to determine the type and sensitivity of monitors to install to cover the full range of possible patient measurements (1E-04 - 1 mSv / h). Measurements of background counts relative to source counts at low source activities with detector shielding of varying thickness were used to determine the optimum shielding. As a result two shielded monitors were chosen and were installed in the ceiling space of the patient therapy room 2 m above the patient’s bed. Measurements of high activity therapy patients are taken using a compensated Geiger monitor and for low activity tracer administrations a NaI detector with MCA is used. Both detectors are controlled from a pc where the detector outputs are stored in formats which allow easy integration of the measurements into an Excel spreadsheet for radiation protection and dose calculations. The user interface for the Geiger monitor was written specifically for this application and is simple to use with minimum prior training. Patient measurements are taken by staff or (more usually) the parents of the child after each patient void. The child has only to lie still on their bed for a maximum of three minutes. In conclusion this system allows whole body retention measurements to be made in identical geometry at regular intervals throughout therapy ensuring high quality data with mimimum disruption to the child.

P558 Activity threshold determining cumulative adverse-effects in patients undergoing peptide receptor radionuclide therapy with Y-90 Octreotate. G. Storto1, A. Speranza1, T. Pellegrino2, M. Panico1, L. Cella1, A. Nardelli2, A. Russo1, M. Klain2, A. Soricelli3, L. Pace2, M. Salvatore2; 1Institute of Biostructures and Bioimages, CNR, University “Federico II”, Naples, Italy, 2 Department of Biomorphological and Functional Sciences, University “Federico II”, Naples, Italy, 3Diagnostic Imaging, Parthenope University, Naples, Italy. Aim: Dosimetry is mandatory for determining ideal tumor-dose and sparing normal tissues in peptide receptor radionuclide therapy with Y-90 Octreotate (PRRT). However, dosimetric procedures are often difficult to perform because of repeated measurements and complex algorithms implementation in patients with a reduced performance status. We aimed to determine whether an activity threshold is conceivable in patients who underwent PRRT. Material and Methods: ICRP recommendations concerning irradiation report that a dose-thresholds exist in determining different somatic adverse-effects which add up to the dose increases. Accordingly, we studied 12 patients (2 W, 48±17 yrs) who underwent PRRT for metastatic neuroendocrine tumors receiving therapeutic activities (mean 2680 MBq; range 1850-3996 MBq). Somatic adverse-effects were evaluated in all patients identifying vomiting and asthenia as main critical symptoms. The onset of the above adverse-effects, alone or concomitant, was used to stratify therapeutic toxicity in our subset. A semi-quantitative tumor uptake assessment was performed, at the same time, on 111-In Octreotate scans using a 4 point-scale with respect to the liver uptake. Disease extension was also determined in each of 5 body regions. Results: All patients presented a score value • 3 and a disease extension involving more than three sites. An administered activity of 3330 MBq of Y-90 was observed as the cut-off above which the onset of both adverse-effects occurred concomitantly. This activity would deliver an effective-dose for free Yttrium of 1.7 Gy (ICRP 30) and, as reported in literature, an averaged effective-dose of 0.5 Gy for Y-90 somatostatin analogues. In addition, according to ICRP for pan-irradiation the cumulative adverse-effects seems to occur about 2 Gy. Conclusion: Our findings indicate that an empiric dose-threshold, settled on the administered activity, may be determined for PRRT patients, that may represents a limiting value for avoiding the combined appearance of somatic adverse-effects.

P559 Dose distribution in therapeutic schemes

Re186hedp

and

Sm153EDTMP

G. Papanikolos, M. Lyra, J. Jordanou, P. Phinou, D. Kontogeorgakos, L. Vlahos, G. Limouris; Athens University, A' Radiology Department, Athens, Greece. Aim. Optimum therapeutic management of patients suffering from metastatic bone pain, requires accurate calculations concerning absorbed dose by metastatic lesions and other critical organs, such as red marrow. Mean absorbed dose, which is the current parameter used to predict the efficacy of the treatment, can either overestimate or underestimate, actual doses delivered in

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Poster Presentation

P554

Optimisation of equipment and methodology for whole body activity retention measurements for children undergoing targeted radionuclide therapy

these organs/tissues of interest (TOIs). This study presents differences in dosimetric calculations derived utilizing parameters from different sources (MIRDOSE3, MIRD Pamphlet No 11 and S values published by Bouchet et al.), in therapeutic schemes with Re186HEDP and Sm153EDTMP. Materials and Methods. Planar scintigraphic images for 2 groups of patients (1 for Re186 patients and the other for Sm153 patients) were obtained: 2 during the first 24h post injection (the last of which at 24h post injection) and 2 more from 24h - 7d post injection. Processing of the obtained images utilizing ROI quantitative methods, previously calibrated with water-phantom measurements, determine residence times and radionuclide uptakes not only by TOIs but by specific skeletal sites as well. Dosimetric calculations were performed using MIRDOSE3 computer code, S values from MIRD Pamphlet No 11 and site specific Re186 and Sm153 S values for several source-target combinations within trabecular and cortical bone, along with cumulative site specific activities derived from values obtained by image processing. Skeletal averaged Re186 and Sm153 S values were also used. Results. Time-activity curves for various skeletal sites were generated for both groups of patients. Absorbed dose distributions along with time - dose rate curves were derived for both red marrow and different regions of the skeleton. Comparisons are made between these parameters and mean absorbed doses calculated using skeletal averaged S values, S values from MIRD Pamphlet No 11 and MIRDOSE3 computer code. Conclusions. Mean absorbed dose calculations, in several cases, result in overestimations and underestimations concerning actual doses in TOIs. Knowledge of dose distribution and time-dose rate curves in TOIs are crucial parameters for the assessment the relative biological effectiveness of either an ongoing treatment or a treatment about to start. They can also predict the possibility of dose escalation through multiple administrations of the 2 radiopharmaceuticals.

P560 Internal Dosimetry Calculations using Mathematical Models of adults with different Sex and Height. Application to the 1 Therapeutic Schemes with In-111-DTPA-D-Phe -Octreotide D. K. Kontogeorgakos, G. S. Limouris, P. Dimitriou, L. Vlahos; University of Athens, Athens, Greece. Aim: The assessment of the radiation dose received by different organs in the body during therapeutic applications in nuclear medicine is an essential element in the evolution of the therapeutic outcome. Mathematical representation of the human anatomy is generally used for internal dose calculations. The aim of the study was to improve the internal dose calculations by taking into account the anatomical and mass changes of the human organs with the body height in order to attempt an individualized patient dosimetry.Materials and Methods: 6 anthropomorphic mathematical models representing 3 males and 3 females with body heights 160, 170 and 180cm and 150, 160 and 170cm respectively were designed. The linear relation between organ mass and body height was adopted by data presented in the literature. The mathematical equations describing the Reference Man Model used in the MIRD scheme were implemented in the construction of the anthropomorphic models of different heights by adapting the shape of every organ in the mass data changing their parameters accordingly. The mathematical models were implemented in the Monte Carlo simulation for the calculation of the absorbed dose per cumulated activity (S value). The simulations were applied during therapy after intra-hepatic administration of In-111-DTPA-D-Phe1-octreotide.Results: The implementation of the models resulted in the S values of all the source and target organs for In111-DTPA-D-Phe1-octreotide intra-hepatic concerning the six mathematical models of different sex and height.Conclusions: The application of the dosimetric models gives the medical doctor the potential of scheduling the therapeutic scheme (number of administrations and total administered activity) for every patient taking into account the dose received by the critical organs and the tumour.The mathematical anthropomorphic models presented in the present study can be used for the design of patient specific dosimetric protocols optimizing the therapeutic applications with radiopharmaceuticals. The results emphasize the need of more patient specific dosimetric models (voxel dosimetry) to represent the anatomical variability of the patient population.

P561 Absorbed fraction and absorbed dose calculation with Monte Carlo simulations on a multicellular tumour model R. Spaic1, R. Ilic2, M. Dragovic1, B. Petrovic3; 1Medica Nucleare, Belgrade, Serbia and Montenegro, 2Institute of Nuclear Science VINCA, Belgrade, Serbia and Montenegro, 3Faculty of Organisation Sciencies, Belgrade, Serbia and Montenegro. Aim: The MIRD schema is the most common method applied in radionuclide therapy which calculates an average absorbed dose of tumour and critical organs. This conventional approach uses macroscopic characteristic of tumours or organs and introduce some assumptions, such as: (a) spatial distributions of administrated activity and calculated absorbed dose was uniform; (b) absorbed fraction for beta emitters is equal one. The aim of this study is to calculate by Monte Carlo simulations absorbed fractions and absorbed doses at cellular level in tumours of different size and to analyse the degree of errors which MIRD assumptions made. Materials and Methods: A multicellular tumour model, which include all relevant parameters of tumour type and growth, is defined as a sphere in which cells are randomly placed and characterised with the cellular volume density. The intracellular to extracellular radionuclide concentration and labelled cell density define the non homogeneity of the radionuclide distribution in the tumour. The FOTELP code was used for Monte Carlo simulations on this three dimensional tumour model. An absorbed fractions for different tumour radius and mass, and homogenous distribution of radionuclide, are calculated and presented as diagrams. Also, absorbed doses are calculated for same tumour with deferent non homogeneity, and presented as dose volume histograms (DVH's). This is done for low energy (Cu-67, I-131) and high energy (Re-188, Y-90) beta emitters which are commonly used in radionuclide therapy. Results: For the tumour of 1 g mass absorbed fraction is between 0.73 and 0.96 for selected radionuclide. The MIRD error define as (1absorbed fraction)x100 is more than 50% for high energy beta emitters and for the tumour with radius under 0.2 cm. The generated DVH's represents absorbed dose of the cells divided with average tumour absorbed dose calculated by MIRD schema. DVH's showed that tumour cells absorbed dose is much lower than is average tumour absorbed dose. The average absorbed doses of the non labelled cells was between 0.62 and 0.80 (for labelled cells was between 3.98 and 6.21) of the average absorbed dose calculated by MIRD approach, for low energy beta emitters.

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The same for high energy beta emitters was between 0.87 to 0.89 (and between 2.35 and 2.68), respectively. Conclusions: Simulations done on 3D multicellular model with FOTELP Monte Carlo code provide accurate informations than MIRD schema approach for radionuclide therapy.

P562 Activity quantification of planar gamma camera images S. Leide Svegborn, M. Sydoff, K. Norrgren; Dept. of Medical radiation physics, Malmö, Sweden. Introduction: The aim of the project was to investigate the parameters involved in the activity quantification of planar gamma camera images, and to determine the individual parameter and total uncertainties. The parameters that were investigated were the correction for background activity, the attenuation and scatter correction for the whole body and for source organs of different sizes and the correction for overlapping organs.Materials and Methods: The study was carried out on an anthropomorphic plastic phantom simulating the torso of a 70 kg male (MIRD). Located inside the torso were organ phantoms simulating kidneys, heart, liver and lungs. The organ phantoms were filled with thoroughly determined activity of the same magnitude as in a realistic patient situation. The torso phantom was filled with activity of various concentrations in order to investigate the background activity subtraction method. Four different methods were investigated. The radionuclides studied were 99mTc and 123I. The measurements (conjugate counting) were carried out using a dual-headed gamma camera, equipped with parallel-hole lowenergy collimator. The sensitivity of the gamma camera was determined for the appropriate scanning geometry. The parameters used in the attenuation correction was obtained in two different ways, either out of transmission measurements using a 57Co flood source or by determination of the effective linear attenuation coefficient from emission measurements on a phantom of tissue-equivalent material.Results: The discrepancy between the estimated activity and the true activity in the organ phantoms for the various correction methods depended on the organ size. The calculated activity in the organ phantoms varied between an underestimation of approximately 80% to an overestimation of about 200% depending on if and what background activity correction method was used. Another major factor influencing the accuracy of the quantification was the attenuation coefficient. A deviation of 0.01 cm-1 from a fixed value of the effective linear attenuation coefficient resulted in an error of up to 15%. In conclusion, in a patient situation it is recommended that the attenuation correction should be based on transmission measurements on the patient. Activity background correction should be done and preferably with a method that takes the total body and the organ thickness into consideration.

P45 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Radionucl.Therapy/Dosimetry: Dosimetry: Quantitative Analysis and Treatment Planning / Dosimetry for Clinical Trials P563 SPECT quantitation: an attempt to determine voxel cumulated activity in order to get a dose volume histogram (DVH) of a thyroid phantom. M. Kotzassarlidou, I. Printzipas, V. Hatzipavlidou, N. Salem, A. Makridou; “TheAGENION” Cancer Institute, Thessaloniki, Greece. Aim: Estimation of the absorbed dose for target tissues using administered radionuclides, firstly require determination of amounts of radioactivity as accurate as possible and secondly calculation of the absorbed dose using the MIRD formula. During this study, voxel cumulated activity of a thyroid phantom was determined using single photon emission tomography, (SPECT), whereas absorbed dose was calculated using voxel S values of the MIRD schema. Finally, a dose volume histogram (DVH), which is representative of three dimensional 3-D dose distribution in the phantom, was plotted. Methods and Materials: A thyroid phantom (3602, Picker Nuclear, volume 35cc) with known amount of radioactivity (1.2 mCi pertechnetate) was imaged by SPECT mode (matrix 128x128, 128 frames, 10 sec/frame). Projections were reconstructed filter back projected (Butterworth, cutoff 1) and voxel counts were measured on the transaxial images. System sensitivity for the same acquisition parameters was determined using a cylindrical Jaszczak phantom. Voxel counts were converted to voxel activity concentration and by using voxel S values from the MIRD pamphlet No 16, dose in each voxel was determined leading to the plot of dose volume histogram.Results: Measured activity was overestimated (~ 10%) whereas volume was in good agreement with the nominal one, comparing dose estimates from the MIRD pamphlet No 1 and 16, they were in good agreement.Conclusions: Based on the above results the method seems to be quiet satisfactory and needs to be further investigated with other isotopes such as I-131, In-111 .

P564 Lu-177 DOTA-TATE for peptide receptor radionuclide therapy (PRRT): organ-, tumor- and blood kinetics C. Wehrmann, S. Senftleben, R. P. Baum; Zentralklinik Bad Berka, Bad Berka, Germany. Aim: Peptide Receptor Radionuclide Therapy (PRRT) with Lu-177 DOTA-TATE is used for the treatment of patients with neuroendocrine tumors. The aim of our study was to determine the organ and tumor kinetics for dosimetric calculations.Materials and Methods: 49 patients (aged 61+/-10 years; 21m, 28f) with metastasized neuroendocrine tumors (somatostatin expression verified before by Ga-68 DOTA-NOC PET/CT) were treated with activities of 2.5-7.0 GBq Lu177 DOTA-TATE (1-3 cycles). On the basis of conjugated planar whole-body scintigraphies 0.5h, 3h, 24h, 48h and 72h p.i. the time-dependent whole-body, organ and tumor activities were determined and dosimetric calculations were performed according to the MIRD scheme using OLINDA software. Blood samples were drawn from 23 patients to estimate the absorbed dose to

P565 Evaluation of biokinetics and thyroid residual dosimtery after recombinant human TSH (rh-TSH)-aided radioiodine therapy for different administered activities S. Fattori1, A. Poggiu1, G. Rossi1, P. D'Avenia1, E. Di Nicola1, P. Marini1, S. Barucca2, A. Berbellini2, F. Capoccetti2, F. Ferretti2, C. Cidda2, S. Sivolella2, E. Brianzoni2; 1Medical Physics Macerata Hospital, Macerata, Italy, 2 Nuclear Medicine Macerata Hospital, Macerata, Italy. Aim Our purpose was to appraise some characteristic quantities of thyroid residuals, as effective halftime, uptake and dose, in thyroidectomized patients affected by differentiated thyroid carcinoma, treated with different activities of radioiodine, after administration of rh-TSH. Materials & methods 37 patients were studied, all administered with rh-TSH in two injections of 0.9 mg each (day 1 and 2). At day 2 all patients’ pre-therapy thyroid uptakes were measured at 20th hour. The patients were randomized in two groups. At day 3 group A (19 patients) was administered with 1850 MBq of I131, group B (18 patients) with 3700 MBq. At 30th and 70th hour they underwent whole-body-scans (WBS) with double-head gamma-camera and neck-scans with pin-hole collimator. Retained activity in the residuals was quantified by means of WBS analysis, after system calibration. Remnant tissue volume was quantified by means of pin-hole scan analysis. In drawing ROIs corresponding to active tissue a display threshold of 30% was chosen. We appraised the uptake of thyroid single residual during therapy, the effective half-life and the dose in the remnant tissue. Mird and S-factors were used. Results Follow-up results were evaluated: two patients in group A and two in group B showed partial remission, the other a complete one. Among the total TR of the residuals (68) and for the 31 residuals of the group A (AR) and the 37 of B (BR) we appraised the main statistical indexes relative to the distributions of effective half-lives and uptakes during therapy. All residuals’ uptake values during therapy were not null (AR: 1.6±2.0 %, median: 0.7; BR: 2.0±2.2 %, median: 1; TR: 1.8±2.1 %, median: 2.1). Analogue results were valid for pre-therapy uptake values for all patients (1.3±1.0 %, median: 0.8) Residuals’ half-lives for groups AR and BR did not result significantly different between them (AR: 3.0±2.0 d, median: 2.7; BR: 2.7±1.9 d, median: 2.6; TR: 2.8±1.9 d, median: 2.65). We also appraised the half-lives distributions for different subgroups chosen on specific uptake (%/g) Three residuals in AR and six in BR received doses less than 300 Gy. Conclusions Collected data conclude that rh-TSH does not challenge the therapeutic effectiveness of radioiodine treatment. Half-life values result independent on administered activity and are comparable with those in literature relative to patients treated in hypothyroidism. We did not point out significant differences in the treatment response between 1850 and 3700 MBq administered activity.

P566 Dosimetry for fractionated 131I-mIBG therapies in patients with primary resistant high-risk neuroblastoma: preliminary results S. Buckley1, G. Flux1, M. Gaze2, S. Chittenden1, M. Partridge1, D. Lancaster1, A. Pearson3, F. Saran1; 1Royal Marsden NHS Foundation Trust, Sutton, United Kingdom, 2University College of London Hospitals, London, United Kingdom, 3Institute of Cancer Research, Sutton, United Kingdom. This study aims to develop a protocol for SPECT-based dosimetry of tumours for use in the SIOP-Europe Neuroblastoma Group pilot study of 131I-mIBG and topotecan therapy with peripheral stem cell support for primary resistant high-risk neuroblastoma. The therapy trial aims to deliver a whole-body dose of 4 Gy in two fractions. For the first treatment a standard activity of 444 MBq/kg is administered. Whole-body retention measurements are used to calculate the whole-body dose received from the first fraction and the activity of the second fraction is adjusted accordingly to give an overall whole-body dose of 4 Gy. The dosimetry protocol must be simple and robust so that data from the multi-centre trial can be compared with confidence despite inherent uncertainties in dose calculations. As two treatment fractions are used this was achieved by comparing ratios of absorbed dose estimates from the two therapies as well as absolute dose estimates. This is based on the rationale that, whilst there may be uncertainties in absolute absorbed dose quantification, these uncertainties are the same for both treatments. Two patients who had relapsed after high dose chemotherapy were treated with 131I-mIBG and topotecan therapy. The tumour dose was assessed by acquiring a minimum of three SPECT scans. These commenced when the remaining patient activity was approximately 1500 MBq and continued daily until discharge. Scans were acquired using a high-energy collimator and a matrix size of 128 × 128. Dead-time and triple energy window scatter corrections were applied. The images were reconstructed using filtered backprojection and a Chang attenuation correction. Two different VOIs were used to assess the reproducibility of the tumour absorbed dose ratios. The ratios of the administered activity and whole-body dose between the two fractions were 1.89 and 2.05 respectively for patient 1, and 0.71 and 0.71 respectively for patient 2. The tumour absorbed

dose ratios estimated for patient 1 were 1.35 and 1.12 respectively, and 1.01 and 0.96 respectively for patient 2. The initial results indicate that tumour effective half-life was the same for each fraction. Our method of studying tumour absorbed dose ratios appears to be reproducible and the measurement is relatively insensitive to the VOI used. This should facilitate accurate data comparison between centres. Currently an accurate method for comparing absolute tumour doses is also being assessed. The accuracy and precision of both methods will be evaluated further as the number of patients in the study increases.

P567 Thyroid remnant and red marrow absorbed dose in thyroid 131 cancer patients submitted to I ablative therapy: comparison rh-tsh stimulation versus hypothyroidism induced by l-thyroxine withdrawal G. Boni1, A. Vaiano2, A. C. Traino2, M. Grosso1, P. Lazzeri1, C. Colato3, M. V. Davì4, G. Francia4, M. Lazzeri2, G. Mariani1, M. Ferdeghini5; 1Centro di Medicina Nucleare, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy, 2 U.O. Fisica Sanitaria, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy, 3Dipartimento di Patologia, Ospedale Policlinico G.B.Rossi, Università di Verona, Verona, Italy, 4Dipartimento di Scienze Biomediche e Chirurgiche, Ospedale Policlinico G.B.Rossi, Università di Verona, Verona, Italy, 5Dipartmento di Scienze Morfologico Biomediche, Sezione di Radiologia – Medicina Nucleare, Ospedale Policlinico G.B.Rossi, Università di Verona, Verona, Italy. Purpose: In thyroidectomized patients, increased TSH levels are requested for enhance the 131I uptake. This purpose was traditionally obtained by the withdrawal of levothyroxine (L-T4) for 46 weeks or triiodothyronine for two weeks. The availability of a genetically engineered version of the recombinant human TSH (rh-TSH) provides an alternative tool to enhance the TSH serum level without inducing hypothyroidism. Aim of this study was to compare the 131I remnant and red-marrow doses calculated in differentiated thyroid cancer (DTC) patients pre-treated with rhTSH with those calculated in patients in hypothyroidism induced by L-T4 withdrawal.Methods: 46 DTC patients, submitted to 131I ablative therapy, were divided in group A (pre-treated with rhTSH) and group B (treated after L-T4 withdrawal for 30 days). The red marrow absorbed dose per unit administered activity and the remnant cumulated activity per unit administered activity were calculated for both groups.Results: The red-marrow dose in 17 rh-TSH treated patients is 0.06 ± 0.02 mGy/MBq; that in 14 hypothyroid patients is 0.09 ± 0.03 mGy/MBq (two-tails unpaired t-test p=0.003). The remnant cumulated activity per unit administered activity in 10 rhTSH treated patients is 0.9±0.8 h; that calculated in 21 hypothyroid patients is 1.55±1.05 h (twotails unpaired t-test p=0.063). This last result is mainly due to the difference between the maximum uptake in rh-TSH (U=0.01±0.01) and hypothyroid patients (U=0.03±0.02) (two tails unpaired t-test p=0.019).Conclusions: The rh-TSH pre-treated patients seem to have a lower uptake compared to those in hypothyroidism induced by L-T4 withdrawal. On the other hand their red-marrow dose seems to be lower.

P568 90

Y microspheres: Comparison of methods for calculating the administered activity in clinical practice

E. Kalogianni, D. J. Towey, S. Khan, A. Al-Nahhas, K. S. Nijran; Hammersmith Hospitals NHS Trust, London, United Kingdom. Intra-arterial administration of 90Y microspheres (SIR-Spheres®) is a treatment option for unresectable liver tumour, which allows the preferential delivery of radiation into the tumours without significant liver toxicity. The administration of the microspheres is performed via a catheter placed in the hepatic artery. Since liver tumours are fed mainly by arterial rather than portal venous blood and the microspheres are unable to traverse the tumour vasculature they stay permanently within the tumour and decay with the physical half-life of 90Y [2]. The purpose of this study is to compare the patient radiation dose as estimated by the BSA (body surface area) method with the partition model, which is based on MIRD theory [3]. 20 patients with unresectable liver tumour have been treated at Hammersmith Hospitals NHS Trust between 22/06/2004 and 30/03/2006. Prescribed activity was calculated using the BSA method (empirical method) that involves the estimation the percentage of lung-shunting as calculated by the 99Tcm MAA perfusion study. It is assumed that the distribution of the microspheres during the treatment is identical with the distribution of the MAA particles during the perfusion scan [1]. The administered activity to these patients ranged between 1.19 to 2.25 GBq (median 1.80 GBq). The percentage of lung shunting was ranged between 2 to 35% (median 4%). Using the partition model the absorbed doses to normal liver, tumour, lung and the maximum activity to accommodate a safe radiation dose to the normal lung (20 Gy) and liver parenchyma (70 Gy) were calculated retrospectively. CT data was used to estimate the liver mass. The tumour-tonormal tissue ratios (T/N) were obtained from the 99Tcm MAA perfusion studies. This study shows that in most cases higher administered activity could be well tolerated. However, in one case the absorbed dose to the lung exceeded the tolerance dose. Although the partition model has many limitations it can be used in accordance with the BSA model to dictate the optimal amount of the administered activity that causes minimum effect to the normal tissue. References 1. Ho S, Lau WY et al, “Partition model for estimating radiation doses from yttrium-90 microspheres in treating hepatic tumours”. Eur J Nucl Med, 23: 947-952, 1996. 2. Salem R, Thurston KG et al, “Yttrium-90 Microspheres: Radiation Therapy for Unresectable Liver Cancer”. J Vasc Interv Radiol, 13: S223-S229, 2002. 3. SIR-Spheres® (Yttrium-90 Microspheres), Technical information. SIRTEX, 2004

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Poster Presentation

the red marrow. To describe the kinetics we used the following parameters: mean half-life and uptake (fraction of injected activity/dose, ID) which were calculated using the fit of the timedependent activity curve to a mono- or bi-exponential function.Results: The renal uptake decreased for the first 3-5 hours p.i. with a mean half-life of 1.3+/-0.6h, followed by a second phase with a longer half-life of 70+/-20h. The maximum kidney uptake was 4+/-1%. The uptake in the spleen increased over 24h p.i. to a maximum of 2+/-0.8% ID and then showed a decline with a half-life of 75+/-18h. The tumor uptake showed an increase until 24h p.i. to a maximum of 0.1+/-0.1% ID and then slowly decreased with a half-life of 80+/-24h. Liver metastases showed a higher maximal uptake (0.12+/-0.1%) as compared to lymph node metastases (0.09+/-0.06%). The blood kinetics were fitted to a tri-exponential function with large variation: half-life 1: 0.2+/0.2h; half-life 2: 2+/-1.8h and half-life 3: 21+/-10h. The following organ absorbed doses were calculated: kidneys: 5+/-2 Sv; spleen: 6+/-2 Sv; metastases: 61+/-82 Sv (47+/-30 Sv for lymph node, and 81+/-119 Sv for liver metastases). The resulting dose to the red marrow was 0.2+/0.1Sv.Conclusions: The relatively low organ doses compared to Y-90 labelled peptides for PRRT correlate with the low clinical toxicity of the radiopharmaceutical. The effective treatment of patients with neuroendocrine tumors using Lu-177 DOTA-TATE is confirmed by the mean absorbed tumor doses. Individual patient dosimetry should be performed due to the large interindividual variations concerning the organ and tumor doses.

P46 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Radionucl.Therapy/Dosimetry: Biological and LongTerm Effects / Animal and in-vitro Studies P569 Comparison of myelotoxicities between 223 Ra in rats

227

Th-EDTMP and

K. Washiyama1, Y. Imakita2, K. Ogawa3, M. Yoshimoto1, R. Amano1, S. Kinuya4, T. Mitsugashira5, K. Kawai1; 1Division of Health Sciences, Graduate school of Medical Sciences, Kanazawa University, Kanazawa, Japan, 2School of Health Sciences, Faculty of Medicine, Kanazawa University, Kanazawa, Japan, 3Central Institute of Radioisotopes Science, Division of Tracer Kinetics, Advanced Science Research Center, Kanazawa University, Kanazawa, Japan, 4Department of Biotracer Medicine, Graduate school of Medical Sciences, Kanazawa University, Kanazawa, Japan, 5 International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Japan. Aim: Thorium-227 (t1/2 = 18.72 d) is a promising Į-emitting radiotherapeutic nuclide for treatment of bone metastases. 227Th belongs to the actinium series and emits Į-particles with an average energy of 5.9 MeV decaying to 223Ra (t1/2 = 11.435 d) . The daughter nuclide 223Ra, which have been used in clinical study for human, also decays via several Į-emitting nuclides to stable 207Pb with emission of about 28 MeV. The decay and growth patterns of radioactivity of 227 Th and 223Ra after accumulation in bone are specific for each nuclide. We attempt here to evaluate and compare the myelotoxicities of 227Th-EDTMP and 223Ra in rats.Methods: Fourweek-old Sprague-Dawley rats were used in this study. Each rat was injected different dose (ranged from 8 MBq/kg b.w. to 8 kBq/kg b.w.) of 227Th-EDTMP or 223RaCl2. The body weight and blood cells (red blood cells, white blood cells, platelet) of each rat were counted before injection and more than 8 weeks after injection.Results: In the case of 223Ra injection, a rat administered 8 MBq/kg b.w. died 9 day postinjection. The rats administered more than 2 MBq/kg b.w. showed transient weight loss and the rats administered more than 250 kBq/kg b.w. showed decrease of white blood cells and platelets. In the case of 227Th injection, a rat administered 8 MBq/kg b.w. died 8 day postinjection. On the other hand, the rats administered 4 and 2 MBq/kg b.w. died 4 week and 6 week postinjection, respectively. The rats administered more than 500 kBq/kg b.w. showed weight loss and decrease of red blood cells, white blood cells, and platelets. Theoretical calculation showed that the total radioactivity of 223Ra and its progeny reached maximum level just after injection, then decrease according to 223Ra half-life. On the other hand, 227 Th and its progeny deposited on bone increases with time and reaches the maximum level about 3 weeks postinjection, and then decays according to 227Th half-life.Conclusions: The 227ThEDTMP and 223Ra showed myelotoxicity in rats with more than 250 kBq/kg b.w. dose administration. The myelotoxicity of 227Th-EDTMP showed specific pattern and may correlate to the decay and growth pattern of 227Th and its progeny radioactivity which generated in vivo after injection.

P570 Experimental studies of radionuclide imaging of receptorsstr2 transgenes J. Wang1, L. Wang2, Z. Wang1; 1Xijing Hospital,FMMU, Xi'an, Shaanxi, China, 2China Railway First Group Co.,Ltd.Xi'an Center Hospital, Xi'an, Shaanxi, China. Objectives: To introduce human sstr2 gene to tumor cell line which does not express the gene, and to investigate the tumor scintigraphy mediated by the receptor.Methods: Reverse transcription-PCR (RT-PCR) was used to amplify hsstr2 cDNA from total RNAs prepared from human embryonic kidney (HEK) 293 cells, and an enkaryotic expression vector of hsstr2 was constructed. In vitro human lung adenocarcinoma A549 cells were transfected with the abve vector, followed by selection with G418. The expression of SSTR2 in the resulting cell clone was investigated by RT-PCR and flow cytometry. The cell clones overexpressing SSTR2 were selected for in vitro receptor radio assay, while tumor scintigraphy was investigated in nude mice bearing A549 tumors overexpressing SSTR2.Results: Human sstr2 gene was successfully cloned.A549 cell clones stably transfected with the above vector was generated, and the expression of SSTR2 in those clones was confirmed by RT-PCR and flow cytometry. Scatchard analysis of 125I-RC-160 and tumor cell revealed that KD=5.65×10-10mol/L, Bmax =2.01×104/cell. In competitive binding assay, IC50=1.88×10-9mol/L. Tumor lesions in nude mice was detected with 99mTc-RC-160 and clear images were achieved at 0.5~1h postinjection. At 24h postinjection images were showed again.Conclusions: It is available to transfer hsstr2 to tumor cell line which does not express the gene and detect the tumor by the receptor-mediated scintigraphy.The optimal time for scintigraphy is 0.5~1h postinjection.

P571 Administered activity and metastatic cure probability during radioimmunotherapy of ovarian cancer in nude mice with 211At-MX35 F(ab´)2 J. Elgqvist; Dept of Radiation Physics, Göteborg, Sweden. The aim of this study was to elucidate the therapeutic efficacy of Į-radioimmunotherapy (RIT) of ovarian cancer in mice. The study was designed to enable the investigation of: (i) the relation between the amount of injected activity, the specific energy in tumor cell nuclei, and the therapeutic efficacy; and (ii) the minimum required activity (MRA), which establishes a reasonable high therapeutic efficacy. The study was performed using the Į-particle emitter 211At labeled to the monoclonal antibody (mAb) MX35 F(ab´)2. Methods: Animals were intraperitoneally inoculated with ~1 × 107 cells of the cell line NIH:OVCAR-3. Four weeks after

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inoculation animals were treated with 25, 50, 100 or 200 kBq 211At-MX35 F(ab´)2 (n = 20 each group). Another group of animals was treated with a non-specific mAb: 100 kBq 211AtRituximab F(ab´)2 (n = 20). One control group was treated with unlabeled MX35 F(ab´)2 (n = 5) and another with unlabeled Rituximab F(ab´)2 (n = 5). At the time of treatment 8 animals were sacrificed and biopsies were taken from the peritoneum to determine tumor sizes using electron microscopy. Eight weeks after treatment the animals was sacrificed and presence of macro- and microscopic tumors and ascites was determined. A metastatic cure probability (MCP) model, based on the numbers of tumors of different sizes present at the time of treatment and the radiation sensitivity of the OVCAR-3 cells, was developed and compared to the experimentally determined therapeutic efficacy. Results: When given treatment 4 wk after cell inoculation the tumor-free fractions (TFFs) were 25, 22, 50, and 61% following treatment with 25, 50, 100, and 200 kBq 211At-MX35 F(ab´)2 respectively, and 11% when treated with 100 kBq 211At-Rituximab F(ab´)2. There was a significant increase in TFF between the 211At-MX35 F(ab´)2 groups as the injected activity was increased (p = 0.008). The specific energy in irradiated cell nuclei varied between ~2 and ~400 Gy. Conclusion: As a highly significant increase in the therapeutic efficacy was observed between the activity levels of 50 (TFF = 22%) and 100 (TFF = 50%) kBq 211 At-MX35 F(ab´)2, the conclusion was that the MRA is ~100 kBq 211At-MX35 F(ab´)2. The difference in therapeutic efficacy between the 100 and 200 kBq levels and the 50 and 100 kBq levels could be anticipated by the MCP model. The failures at the activity levels •100 kBq could be explained by cell nuclei receiving zero specific energy in the core of large tumors.

P572 Survival Rate of peritoneal rat macrophages after the exposure to different irradiation doses C. S. Ferreira1, G. S. Almeida1, H. F. Tavares1, J. Marques1, J. P. Castro1, M. J. Bartolo1, M. C. Lopes2, A. C. Santos3, M. F. Botelho3; 1Faculty of Science and Technology of University of Coimbra, Coimbra, Portugal, 2 Portuguese Cancer Institute - Center Region, Coimbra, Portugal, 3 Biophysics/Biomathematics Institute, IBILI, Faculty of Medicine, Coimbra, Portugal. Introduction: The effects of ionizing radiation has been widely studied, but it is not fully understood. With this study we intend to contribute to the evaluation of the survival rate of rat macrophages, the first line of organism defence, after the exposal of two macrophages cell line cultures to an ionizing radiation field of 3 Gy and 6 Gy, respectively. We aim to compare the eventual biological effects with a similar culture that has not been irradiated. To evaluate the macrophages viability we used the MTT test [3-(4, 5-dimethylthiazolyl-2)-2, 5diphenyltetrazolium bromide].Materials and Methods: The rat peritoneal macrophages were collected from Wistar rats (2 months old). The cells were cultured in a flat bottom multiwell cluster, and incubated at 37ºC with 5% CO2. The cells were separated in 3 groups: group I control group; group II - cells irradiated with 3 Gy; and group III - cells irradiated with 6 Gy, by a particle accelerator Varian - Clinac 600C of photons, 4 MeV. After irradiation the multiwell cluster was placed in the incubator for 2h30. This time was considered our time-0 (T0); time1(T1) = 8h after irradiation; time-2 (T2) = 48h after irradiation; time-3 (T3) = 58h after irradiation. The viability of the cells was studied using the MTT test. Only living cells with active mitochondria are able to incorporate this dye. After acid treatment blue crystals are formed. Visual control was preformed with an inverted microscope and the colour intensity was measured by ELISA (570nm, ref. filter 620nm).Results: The cell survival of the control group, for every time was considered as 100%. For T0 macrophages (2h30m) the cell survival was 100% for all cultures (control, 3 Gy and 6 Gy); for T1 (8h) cell survival was 90% for 3 Gy and 80% for 6 Gy; for T2 (48h) 71.43% and 28.60% were obtained; and for T3 (58h) we determined

70% for 3 Gy and 25% for 6 Gy. Discussion & Conclusions: The irradiation of rat macrophages with 6 Gy is the most harmful, showing death of the majority of the cells. The 3 Gy radiation is also aggressive but enables a higher survival rate. Time is also an important factor and the cell death is proportional to it. The number of living cells decreased with time and higher doses.

P573 Study of the acute radiation effects in amniocytes using Xray I. M. Aleixo1, I. Rolo1, L. F. Neves1, R. M. Costa1, R. Cordeiro1, M. C. Lopes2, M. Pinto3, I. Carreira3, A. C. Santos4, M. F. Botelho4; 1Faculty of Science and Technology of University of Coimbra, Coimbra, Portugal, 2 Portuguese Cancer Institute - Center Region, Coimbra, Portugal, 3 Laboratory of Cytogenetics, Institute of Biology, Faculty of Medicine, Coimbra, Portugal, 4Biophysics/Biomathematics Institute, IBILI, Faculty of Medicine, Coimbra, Portugal. Aim: In this work we intend to contribute to the study of the acute behaviour of human amniocytes with radiation. To evaluate how these cells react to X-Ray radiation we used both cytogenetic and MTT test approaches.Materials and Methods: The amniocytes were isolated from the amniocentesis and culture under aseptic conditions. After the cell culture (37ºC, 5% CO2), the amniocytes were irradiated with X-ray (4 MeV) with a dose intensity of 3 Gy and 6 Gy during 67.2 s (289 m.u.) and 134.4s (560 m.u.), respectively. One hour after the irradiation, 100 µl of colcemide was added to the samples in order to inhibit the achromatic fuse. The samples were kept during three hours at 37ºC (Heraeus Instruments Incubator function line EG 110I, Line A JOUAN, SHELLAB). The manipulation and fixation of the cells for the cytogenetic evaluation were done 4h (t0), 24h (t1), 120h (t2) and 144h (t3) after the irradiation. The plates containing the fixed cells were observed at an optic phase contrast microscope (NIKON Japan 60). To evaluate the cell proliferation and cytotoxicity effects of the radiation on these cells we used the colorimetric MTT test [3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] (SigmaAldrich, St. Louis, Missouri, the USA) to detect living cells 6:30h, 42:30h, 120h and 146h after irradiation. The images were observed under an inverted microscope (phase contrast - NIKON Eclipse TS 100) and the colour intensity was measured by ELISA (570 nm, ref. filter 620 nm).Results: In the cytogenetic study, at t1 and t3, the cells irradiated with 6 Gy showed more damage and/or isolated pieces of the chromosomes comparing with the cells that were irradiated with 3 Gy. The cell surviving was in both samples (3 Gy and 6 Gy) along time, and we observed

P574 Cytotoxicity and DNA damage induced by intracellular indium-111-oxinate A. J. Weeks1, P. J. Blower2, D. Lloyd1; 1University of Kent, Canterbury, United Kingdom, 2King's College London, London, United Kingdom. Aim: Indium-111-oxinate is a radiopharmaceutical that decays by electron capture with a half life of 67 hours, emitting gamma radiation with energies of 172 KeV and 246 KeV as well as low energy Auger electrons. Indium-111-oxinate is used in nuclear medicine for the in-vitro labelling of separated blood cells, which are then administered to patients to investigate inflammation at the sites of infection and abscesses. It is taken up non-specifically in cells by virtue of its lipophilicity and intracellular dissociation. Because of the potential toxicity of its Auger electron emissions, indium-111 conjugated to octreotide has also been evaluated recently as a therapeutic radiopharmaceutical. It is therefore of interest to investigate the DNA-damaging damaging effects and cytotoxicity associated with cellular exposure to indium-111. Materials and methods: We have investigated cellular toxicity of indium-111, delivered intracellularly as its oxinate complex, in HT1080 fibrosarcoma cells using the colorimetric MTT assay. The results were compared with data obtained from similar experiments in which cells were treated with equimolar amounts of indium-111-oxinate that had been subjected to several weeks of decay, in order to determine the degree of cytotoxicity attributable to radioactive emissions. The single cell gel electrophoresis (Comet) assay was also used to determine DNA damage associated with exposure to indium-111. Results: HT1080 cells that were incubated with indium-111-oxinate at 2 MBq/ml exhibited 95% cellular survival compared to untreated control, while treatment with a molar equivalent of the decayed indium-111-oxinate exhibited 86 % survival compared with the same control. The Comet assay revealed no detectable DNA damage after treatment of HT1080 cells with up to 2 MBq/ml indium-111-oxinate. Conclusions: Radioactive emissions associated with up to 2 MBq/ml indium-111 oxinate (a concentration comparable to that used clinically for labelling leucocytes and that likely to be reached in tumour cells during radionuclide therapy) do not elicit significant DNA damage or cytotoxicity in HT1080 cells. Studies are continuing to investigate the toxicity and DNA damage and repair induced by indium-111 in different cell types and at increased doses, in relation to sub-cellular distribution and P53 expression.

P575 Organ specific bremsstrahlung imging using whole body phantom A. K. Shukla, S. C. Kheruka, U. Kumar; Sanjay Gandhi Postgraduate Institute Of Medical Sceinces, Lucknow, India. Introduction: The therapeutic use of incorporated beta emitting radionuclides such as 32P and 90Y has registred phenomenal growth in past few decades resulting into a wide variety of clinical applications.The emergence of areas like Radiosynovectomy and Infusional Brachytherapy have been proved to be effective clinical tools to help providing therapy in a wide variety of clinical conditions.The present study was conducted to delineate the application of bremsstrahlung imaging using whole body Phantom in thoracic ribs,vertebra and Liver.Materials and Methods: The bremsstrahlung imaging for various levels of activities incorporatde in the 4th rib( 5.0 MBq ), 7th rib( 51.0MBq ), 4th vertebra( 15.00 MBq), 8th vertebra( 63.00 MBq ) and Liver ( 82.27 MBq ) was performed on a SPECT gamma camera using medium energy collimator and prestandardized imaging parametres i.e. widow of 30-228 KeV,matrix size 256 X 256,acquisition time of 300 seconds and zoom of 1.00.The images were acquired with and without breast attenuation using whole body phantom. Results & Conclusions:Regions of interest drawn on the areas representing incorporated activities in the phantom provided total counts corresponding to various levels of incorporated activities of 90Y to enable quantification. The quantification revealed total conts of 6745 and 8297 ( anterior with and without breast attenuation ) in the 4th rib whereas this region could not be visualized in the posterior view.Similarly total counts of 6578 and 8984 ( anterior with and without breast attenuation ) were observed in the 7th rib while a total counts of 38456 and 41669 ( with and withou breast attenuation ) were seen in the posterior view of the image( source fixed posteriorily).Image corresponding to T4 vertebra anteriorily showed total counts of 6514 and 7680 ( with and without breast atteuation).The image corresponding to T8 vertebra in the anterior view revealed total counts of 13529 and 13930( with and without breast attenuation ) whereas the posterior image indicated total counts of 24847 and 27342 ( with and without breast attenuation ).The total counts in the liver image were observed to be 944745 in the anterior view with breast attenuation whereas this value incrased to 1077370 without breast attenuation.In the posterior image of the liver,only backgroud counts could be seen. This modality offers immense potentiality to not only have precise localization of the incorporated beta emitting radionuclides but also help understanding the kinetics as well as dosimetry subsequent to their instillation for therapeutic purposes.

anti-inflammatory effect of 166-Holmium-phytate injection.Methods: Phases I-II, randomized, simple-blind, placebo-controlled comparative study using increasing dosage. 31 patients suffering from chronic synovitis, rheumatoid arthritis and seronegative spondylarthritis were examined. Patients: Gender (male/female): 12-19; Diagnosis (RA / SNSA): 21/10; Stage of knee joint x-ray (I/II): 7/24; Duration of synovitis (years): 7.9; Duration of disease (years): 5.72; Number of punctures before the Ho-166 treatment: 18.76; Number of steroid injections before the treatment: 18.85. The protocol commenced with screening. Patients were randomly distributed into four treatment arms: Group I. Holmium phytate injectable suspension marked by 185 MBq 166Ho + 40 mg of 1 ml triamcinolone acetonide/TA/ + 1 ml of 1% lidocaine injection./Lid.inj./ Group II. 555 MBq 166Ho. + 40 mg of 1 ml TA + 1 ml Lid.inj. Group III. 925 MBq 166Ho + 40 mg 1 ml TA + 1 ml of 1% Lid.inj. Group IV. Solely 40 mg of 1 ml TA + 1 ml of 1% Lid.inj. There were 48 month follow-up period after the administration of the isotope. The patients were selected according to inclusion and exclusion criteria. Inflammatory activity of the affected knee-joint was tested prior to treatment, and the 14th and 28th days, and 3, 6, 9, 12, 24, 36 and 48 months after treatment. Testing was done based on the following parameters: Measurement of swelling of knee-joint [cm]; Flexion - heal buttocks distance [cm]; Degree of knee-joint pain. Visual Analogue Scale /VAS-1-100/; Patient’s opinion on inflammation of knee-joint /VAS-1-100/; Doctor’s opinion on given inflammation of kneejoint /VAS-1-100/Results: Even after 4 year period 88.2% of the findings were rated as excellent or good. 86.66% of the patients do not need another punction even after a 4 years period. We found no deviations in either haematological or chemical parameters during the study period. We did not detect symptoms of radiation sickness. During the study period, inflammation decreased in the group receiving 555 and 925 MBq.Conclusions: Ho-166 isotope is an effective radiopharmacy treating synovitis. Due to its physical parameters it is optimal to treat large joints (knee) and medium size joints (hips, shoulder, elbow, wrist, ankle). Effective dosage is 555-925 MBq.

P47 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Pediatrics P577 The value of fist-pass radionuclide angiography and perfusion lung scintigraphy in prognosis of pulmonary hypertension in children with congenital systemic-topulmonary shunts Y. B. Lishmanov, K. W. Zavadovskiy, S. N. Ivanov, N. G. Krivonogov, T. P. Kondratjeva; Institute of Cardiology, Tomsk, Russian Federation. Aim. To investigate the prognostic value of fist-pass radionuclide angiography and perfusion lung scintigraphy in congenital systemic-to-pulmonary shunts children with pulmonary hypertension. Material and methods. We examined 45 septal defects patients (aged 5-17), who were divided into two groups: I - with pulmonary artery systolic pressure (PPA) less or equal to 25 mmHg; II - with pulmonary artery pressure more than 25 mmHg. Fifteen healthy children without pulmonary hemodynamics disturbances were controls. Twenty nine patients underwent surgical (n=16) or endovascular (n=13) congenital heart defect correction; seven patients were inoperable. The first-pass radionuclide angiography (FPRA) was performed with 99mTc-DTPA (0.5-1.0 MBq/kg). For postoperative pulmonary artery pressure decreasing prediction we executed FPRA thrice: at rest; 3 min after sublingual administration of 10 mg nifedipine; one hour after i.v. administration of enalaprilate (Enap 1.25 mg in drops). The time of radionuclide bolus transit throughout arterial (TAM) and venous (TVM) sections of pulmonary hemodynamics, and the right ventricle half-evacuation time (T1/2RV) were assessed. To estimate regional and diffuse perfusion abnormalities we performed perfusion lung scintigraphy with 99mTc-albumine microspheres (99mTc-MAA). Results and discussion. Pulmonary artery pressure was in positive correlation with TAM (r=0.48; p=0.01) and T1/2RV (r=0.48; p=0.02). In all first group patients congenital heart defect correction realized in PPA and other pulmonary circulation parameters normalization. In preoperative period these patients had different reaction for the vasodilatators. Lung perfusion pattern was normal in all patients. Among children with PPA>25 mmHg in preoperative period we discovered both increasing and decreasing of TAM and T1/2RV. It turned out that pulmonary haemodynamic normalization in postoperative period occurred in patients with TAM and T1/2RV increasing. And vice versa in patients with TAM and T1/2RV decreasing residual pulmonary hypertension was diagnosed. It may be explained on the one hand by residual imbalance in vascular tonus regulation, on the other hand by morphological changing in vascular wall. In inoperable patients (because of high risk of postoperative acute right ventricle failure) TAM and T1/2RV decreasing predominated. In inoperable patients and in children with residual pulmonary hypertension we discovered mottled lung perfusion pattern that pointed either to local or diffuse circulatory disturbances. The expression of these symptoms was directly proportional to pulmonary artery pressure. Conclusion. The performing of first-pass radionuclide angiography with vasodilatators and perfusion lung scintigraphy is recommended to patients with pulmonary artery pressure more than 30 mmHg. It allows predicting postoperative pulmonary artery pressure normalization.

P578

P576 166

4-years results with Holmium-phytate treatment of chronic synovitis. Phase I-IIa, randomized, increasing dosage, singleblind, placebo-controlled comparative M. Szentesi1, S. Takács1, Z. Farbaki1, E. Nagy1, P. Géher1, J. Környei2, M. Antalffy2, J. TörkĘ2; 1Semmelweis Univ., Chair of Rheumatology and Physiotherapy, Budapest, Hungary, 2Institute of Isotopes Co. Ltd.,, Budapest, Hungary. 166-Holmium-phytate produced by us: radiation type beta energy maximum: 1.84 MeV; radiation type gamma energy maximum: 0.66 MeV; soft tissue penetration: maximum 8.4 mm; average: 3.3 mm; half-life: 26.9 hours; particle size: 0.6-2 µm Study objectives: Examination of

Effectivity of SPECT to evaluate pulmonary perfusion status of children with bronchiolitis obliterans H. Yüksel1, E. Sayit Bilgin2, F. Aras2, S. Tarhan3, Ö. Yılmaz1, G. Gumuser2, A. Sogut1; 1Celal Bayar University, Department of Pediatrics, Manisa, Turkey, 2Celal Bayar University, Department of Nuclear Medicine, Manisa, Turkey, 3Celal Bayar University, Department of Radiology, Manisa, Turkey. Aim: Bronchiolitis obliterans (BO) in childhood which is a potentially severe process of extensive airway narrowing after lower airway injury lead to pulmonary parenchymal perfusion defect. Prognosis is correlated with parenchymal perfusion has been proposed. To correlate the the single photon emission computed tomography (SPECT) perfusion scan to the helical computed tomography (CT), which is gold standart for diagnosis of BO in the diagnostic

S341

Poster Presentation

that cells were able to recover, however we can detect a more significant recovering in the ones irradiated with 3 Gy. Using the cytotoxicity test we observed that, with time, the rate of living cells decreased, varying from 88.89% to 66.66% in the 3 Gy sample and from 70.37% to 45.94% in the 6 Gy.Conclusions: The cell line studied showed, after irradiation in our conditions, a significant decrease of survival rate. However, it is able to recover, with a proliferative rate that is correlated with the intensity of the irradiation.

approach and in the management of BO patients.Methods: Our series consisted of 13 patients (3 female, 10 male, mean age: 4.37±3.73 years). They underwent lung perfusion scintigraphy (LPS) and CT in the same week. One experienced radiologist/nuclear physician evaluated LPS and CT separately. Perfusion scans were acquired in SPECT technique employing a double headed camera ( Infinia, GE, Tirat, Hacermel, Israel), in 128x128 matrix, 30 steps of 30 seconds each, Hann filter, cutoff at 0.9. Planar images in eight directions were also acquired.Results: : Perfusion defect was detected in 60 segments in planar images, 82 segments in SPECT images, 83 segments in CT images. Although SPECT and CT showed more perfusion defects, there is no statistically significant difference between planar and SPECT images; between planar and CT images in detecting perfusion defects (p>0.05). The correlation between SPECT and CT was found to be statistically significant (p<0.05). Discussion: Perfusion SPECT has an advantage to overcome the motion artifact due to breath hold in children in CT images. Perfusion SPECT has the ability of identifying hypoperfused areas detected in planar images more clearly and improves the diagnostic accuracy. SPECT can be used as a valuable technique in the evaluation and in the follow up of the parenchymal lesions of the children with BO.

P579 Evaluation of a new method for the routine quantification of postvoid residual bladder volume R. Malveiro1, A. I. Santos2, P. Almeida1; 1University of Lisbon, Faculty of Sciences, Biophysics and Biomedical Engineering Institute, Lisbon and Nuclear Medicine Department - Hospital Garcia de Orta, Almada, Portugal, 2 Nuclear Medicine Department- Hospital Garcia de Orta, Almada, Portugal. Aim: The purpose of this study was to develop and evaluate a new method for quantifying Postvoid Residual Bladder Volumes (PRBV), suitable for routine clinical use.Materials and Methods: The data collected were precise measurements of the Total Saline Instilled (TSI) and Total Void Volume of urine (TVV) during the Direct Radionuclide Cystography (DRC) study, from which Maximum Volume of Bladder Filling (MVBF) was estimated. We used a precise relationship between the number of counts per pixel measured in DRC images and the number of mL present on the bladder, according to the expression: C=[(MVBF+IBV)/PBC] (mL/cts), where IBV is the Initial Bladder Volume equal to TVV-TSI (mL) and PBC is the number of counts obtained on a Region of Interest (ROI) drawn over the bladder and reflux (if present) on the prevoid bladder image. The value of PRBV is obtained though the expression: PRBV=C*CB (mL), CB being the number of counts obtained applying the bladder and reflux ROIs on post voiding image. We correlated, through Spearman Rank Correlation test, the PRBV values obtained with those calculated following both methods published on EANM Paediatric Guidelines for DRC: PRBV1 and PRBV2, based on formulas using voided volume of urine and volume of fluid infused, respectively. A total of 83 patients were evaluated, 38 males and 45 females, with a mean age of 3,9 years. Of these, 43 did not have Vesicoureteral Reflux (VUR), 18 had bilateral VUR, 13 had left VUR and 9 had right VUR. The following types of bladder fillings were taken into account: single instillation (SI), multiple instillations (MI) and instillations with initial resident bladder volume (IRBV).Results: We found statistically significant correlations between PVRBV calculated by our method and the values obtained using the EANM guidelines: for the whole population (83 patients): r=0.9747 to PVRBV1 and r=0.9974 for PVRBV2; for SI (44 patients): r=0.9900 to PVRBV1 and r=0.9992 for PVRBV2; for MI (20 patients) : r=0.9466 to PVRBV1 and r=1.0000 for PVRBV2; for IRBV (14 patients) : r=1.0000 to PVRBV1 and r=0.9945 for PVRBV2.Conclusions: The results obtained suggest that the method developped, easily available through dedicated software, may be useful for the routine quantification of Postvoid Residual Bladder Volume. It is also valid in all situations, even in those with multiple instillations and/or when complete emptying of the bladder, previous to the exam, was not achieved.

P580 99mtc-dmsa absolute uptake: normal pediatric values at 2-4 hours I. Roca Bielsa1, M. Catala2, J. Bosch2, N. Ferran3, A. Garcia-Burillo4, E. Lopez5, S. Aguade1, J. Castell1; 1Hu Vall Hebron, Barcelona, Spain, 2HGG, Granollers, Spain, 3Hu Bellvitge, Barcelona, Spain, 4Gammadelfos, Barcelona, Spain, 5Gammadelfos, Barcelona, Spain. This study describes the values of absolute DMSA uptake found in a large series of children submitted to a quantitative DMSA scintigraphy, valuing both the absolute tubular uptake (ATU) and the individual absolute uptake of each kidney. The aim of this study is to evaluate the variability of these parameters and if possible to describe their normal range of values. We retrospectively studied 419 patients (186 M, 233 F, mean age 2.04 years, range 0-18 years) submitted to a quantitative DMSA scintigraphy (suspicion of acute pyelonephritis -APN-, follow-up of APN, reflux nephropathy, renal trauma). For the quantitative DMSA scintigraphy, firstly the dose is adjusted to the body weight according to the EANM Paediatric Committee dose calculation schedule. Just before and after the tracer injection, the syringe as well as the needle in acquired on the gammacamera. Renal quantitative frames are acquired 2 to 4 hours after the tracer injection (mean 3,2 hours). A dedicated software calculates the bilateral as well as the right and left kidney ATU, correcting for decay, weight, height and renal depth. In the table below are summarized the obtained values (mean +/- 2 standard deviation):

n

Bilateral ATU

RK ATU

LK ATU

0 - 0.5 years

112

35.1 +/-16.2

17.3+/-8.0

17.8+/-8.5

>0.5 < = 1 years

59

43.4 +/-16.6

21.4+/-9.5

22.0+/-8.7

>1 <= 2 years

91

47.2+/- 15.2

23.8+/-10.2

23.5+/-10.2

>2 years

157

46.0+/- 19.4

22.02+/-14.7

23.9+/-19.0

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Bilateral ATU increases with the age, specially during the first 6 months. In the different ranges of age (0-6 months, 6-12 months, 1-2 years, 2-18 years) the values follow a normal distribution, and the absolute uptake values for each kidney are described. Even there is an increase with age of the ATU values, relatively high values have been found in this series during the first year of life, and specially during the first 6 months of life.

P581 Comparison of glomerular filtration rate measurement with two plasma sample method and serum cystatin C level in paediatric population F. Aydın1, A. K. Cengiz1, F. Güngör1, Ö. A÷2, V. Hazar2, A. G. Güven2; 1 Akdeniz University School of Medicine Department of Nuclear Medicine, Antalya, Turkey, 2Akdeniz University School of Medicine Department of Paediatrics, Antalya, Turkey. Aim: Glomerular filtration rate (GFR) is generally considered the best functional measure among several important functions of the kidney. Cystatin C is a nonglycosylated basic protein produced at a constant rate by all nucleated cells and eliminated by glomerular filtration. Recently, cystatin C has been studied as an alternative marker of GFR. The aim of this study was to compare measured GFR by two-plasma sample method (TPSM) with serum cystatin C level in paediatric population. Materials and Methods: The study population comprised 23 consecutive patients ( 15 boys, 8 girls; mean age 8.3 ± 3.5), included thalassemia (n=14), acute lymphoblastic leukemia (n=5), and fanconi anemia (n=4). Blood samples were taken at 120 and 240 min post-injection of 37-74 MBq of Tc-99m DTPA from the contralateral arm. Slope-intercept method was used for TPSM GFR measurements. Serum cystatin C level was also measured on all patients. Results: TPSM GFR values varied between 50-150 ml/min/1.73m2 (mean: 105 ± 25 ml/min/1.73m2 ). Serum cystatin C levels ranged from 0.32 to1.20 mg/L with a mean of 0.84 ± 0.23 mg/L. There were not statistically significant correlation between TPSM GFR and serum cystatin C level. Conclusion: This study showed that GFR estimation by serum cystatin C level is insufficiently reliable and TPSM should be used in the measurement of GFR in paediatric population.

P582 Indirect radionuclide sistography, Tc99m-DMSA and renal ultrasonography findings in evaluation of nocturnal enuresis and diurnal enuresis G. Koca, K. Demirel, R. Orak, E. Özdemir, S. Türkölmez, M. Korkmaz; Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey. Aim: There is not sufficent research data on reflux positivity for voiding dysfunctions and vesico-urethral reflux (VUR) although the relationship between them was well established. Therefore, we aimed to evaluate children with urinary incontinance, who referred for our clinic for indirect radionuclide sistography (IRNS) retrospectively.Materials and Methods: Seventynine pediatric patients (47 female, 32 male), who had bladder control (at least six mounth) and referred for our clinics during 2004-2006 years. Indirect radionuclide sistography was applied on enuresis complaint patients with an age mean of 8.27 ± 2.21 (min:3, max:15). VUR was diagnosed by IRNS and classified according to the grades proposed by the "International reflux study on children". Tc99m-DMSA and ultrasonagraphy (US) findings of those children were also evaluated.Results: Vesicourethral reflux was (+) for 11 children in nocturnal enuresis group and 13 children in diurnal enuresis group. While children in these groups were investigated, 32 ( 40.5 %) of them had nocturnal enuresis and 47 ( 59.5 %) had diurnal enuresis. Tc99m-DMSA scintigraphy was normal in 54 of 61 patients. On the other hand three patients in nocturnal enuresis group and four in diurnal enuresis group has abnormal Tc99m-DMSA scintigraphy findings. During US evaluations of 68 patients, 50 were normal while 18 were abnormal (8 in nocturnal enuresis and 10 in diurnal enuresis). There were no significant statistical differences between groups for age, gender, IRNS, Tc99-DMSA, and US (p >0.05).Conclusions: Although there were no significant statistical differences for renal complication between diurnal and nocturnal enuresis groups, since pathologic renal problems are more frequently reported in children with voiding disorders, We feel that there is a need for more research on this subject together with other voiding dysfunctions.

P583 Multidisiplinary approach to hydronephrosis diagnosed at antenatal period. F. Aydın1, F. Güngör1, M. Ça÷lar2, E. Alimo÷lu3, E. Güntekin4, G. Karagüzel2, A. G. Güven5, M. Meliko÷lu2; 1Akdeniz University, School of Medicine, Department of Nuclear Medicine, Antalya, Turkey, 2Akdeniz University, School of Medicine, Department of Paediatric Surgery, Antalya, Turkey, 3Akdeniz University, School of Medicine, Department of Radiology, Antalya, Turkey, 4Akdeniz University, School of Medicine, Department of Paediatric Urology, Antalya, Turkey, 5Akdeniz University, School of Medicine, Department of Paediatric Nephrology, Antalya, Turkey. Aim: In this study, it was aimed to evaluate the usefulness of a common algoritm in postnatal diagnosis, treatment and follow-up of the patients diagnosed hydronephrosis at antenatal period. Materials and methods: Between 1993 and 2005, 71 cases (16 girl, 55 boy) who underwent dynamic renal scintigraphy and diagnosed hydronephrosis at antenatal period were included in this study. All patients were followed according to a common algoritm developed by paediatric urology team (Departments of Nuclear Medicine, Radiology, Paediatric Surgery, Paediatric Urology, Paediatric Nephrology). The results of the management were evaluated retrospectively. Results: Right hydronephrosis was determined in 26% of the patients, left hydronephrosis in 45% and bilateral hydronephrosis in 29%. Follow-up ranged from 2 months to 9 years. Diagnostic distrubition of the patients were as follow: Ureteropelvic junction (UPJ) obstruction 38%; non-obstructive hydronephrosis, 32%; vesicoureteral reflux, 7%; multicystic dysplastic kidney, 6%; ureterevesical junction obstruction, 4%; double collecting system 4%, other

P584 Predictive model of renal scar in infants after the first episode of urinary tract infection: impact of vesicoureteral reflux. B. Orive1, J. Elorz2, A. Rodriguez1, J. Cortés3; 1Hospital Txagorritxu, Vitoria, Spain, 2Hospital Basurto, Bilbao, Spain, 3Hospital Santiago Apostol, Vitoria, Spain. Background: first-time urinary tract infection (UTI) occurred most often in infants. A substantial number of them may have vesicoureteral reflux (VUR), which would put them at risk for permanent renal damage. The detection of renal cortical lesions by means of radioisotopes is one of the most widely used techniques in the field of Paediatric Nuclear Medicine. Renal scar is defined as a defect in the renal outline with little or no DMSA intake. Retrospective studies have shown that the presence of VUR does not identify a susceptible population with an abnormal kidney on DMSA and there is a debate over the role of VUR in children who develop renal scars following UTI. The objective of this study was to analyse clinical, biochemical and imaging parameters associated with definitive renal scar after the first episode of UTI in infants.Materials and Methods: prospective study of 383 infants with first episode of febrile UTI. DMSA scan was performed six months after UTI. We analysed as predictor variables of renal scarring: age, sex, leucocytosis(>15000), CRP(>20 mg/l), fever before treatment, ultrasonography and voiding cystourethrograhy. The analysis of frequencies was accomplished through Ȥ2test. Variables with a p<0,15 in univariant analysis were included in a logistic regression. Variables with a p-value <0.10 were considered to be independently related and were included in the predictive model. Reliability of the model was quantified using the Hosmer and Lemeshow test. The adjusted coefficients were used to assign a score risk for every patient and a ROC analysis was used to measure the ability of the risk model to discriminate between normal and abnormal DMSA.Results: 41 infants (10,7%) presented renal scars. CRP, pathological renal ultrasound, reflux and grade of reflux were related significantly to abnormal DMSA (p=0,004, p<0,001 and p<0,001 respectively). The logistic regression model resulted highly predictive (p<0,001), classifying correctly 90,6% of patients. The Hosmer and Lemeshow goodness-of-fit test was not significant (Ȥ21,43; 4; p 0,84). Controlled for other variables, high reflux(grades 4 and 5), OR 17,6 (CI 95% 4,3-72,6); small reflux(grades 1 to 3), OR 3,4 (CI 95% 1,5-7,4); CRP higher than 20 mgr/l , OR 4 (CI 95% 1,4-11,5) and abnormal ultrasound, OR 4,1(CI 95% 1,9-8,8). The area under curve was 0,82 (CI 95% 0,74-0,89).Conclusions: we emphasize the importance of vesicoureteral reflux, especially high grade reflux, as the main factor associated with permanent renal damage. Cystourethrography should be performed in infants with first febrile UTI.

bladder and pelvic sphincter caused by the neural tube closing defect can cause problems in the bladder’s storage and emptying functions and lead to high intravesical pressures, which can in time cause renal damage or failure. Our aim is to determine the affectivity of DMSA scintigraphy in establishment of renal parenchyma damage in patients with SB.Methods: A group of 21 children (12 female, 9 male, age range, 1-13 years; mean age, 7,3 ±3,8 years) with SB and neurogenic bladder was evaluated. All patients were examined for renal scarring with DMSA renal scans and urinary system USG. Catheterized urine cultures were obtained. Blood urea, creatinin levels were measured and creatinin clearance was calculated.Results: Of 21 children 13 (61.90 %) had positive urine culture results. VUR in different grades were found in 10 children (47.62 %). Blood urea, creatinin levels were measured as increased in only one patient (4.76 %). Bilateral increased parenchyma echogenity and gross dilatation in renal units in two children (9.52 %) and bilateral minimal dilatation in two children (9.52 %) were observed with USG. In the evaluation of DMSA scintigraphy, bilateral renal scar was found in 10 patients (47.61%) and unilateral renal scar in 2 patients (9.52 %). In 9 patients (42.85 %) DMSA scintigraphy was normal.Conclusions: Our findings proved that DMSA scintigraphy is the most valuable method in detection of renal parenchyma scar in early stage before renal failure appeared and in the fallow up of the patients with SB.

P587 Kidney Scarring in children after Urinary Tract Infection with and without Vesicoureteric Reflux A. Afgan1, D. Tasovac Ponomarev1, A. Peco Antic2, M. Kostic2; 1KBC Zvezdara, Belgrade, Serbia and Montenegro, 2University Pediatric Clinic, Belgrade, Serbia and Montenegro.

P585

UTI in children is an important clinical problem. Renal scarring occurs most frequently in patients with pyelonephritis and is, generally, associated to vesicoureteral reflux. It is well established that the risk of developing a renal scar increases accordingly to the degree of reflux. The aim of this study was comparison of results 99mTc- dimercaptosuccinic acid (DMSA) renal scintigraphy in children 6 months or later after the first acute episode of urinary tract infections (UTI) and vesicouretheric reflux (VUR) to results in children without VUR. The study included 256 children investigated by 99mTc- DMSA renal scintigraphy and micturating cystourethrography (MCU). We examined 142 children (105F/37M; mean 5.7 years) after acute episode UTI without VUR and 114 children (66F/48M; mean 4.25 years) with VUR. In 57 of them grade of VUR was I-II, in 32 grade III, in 16 grade was IV and in 9 grade of VUR was V. Findings of 99mTc-DMSA renal scintigraphy were classified as: 1. without pathological findings, 2.dilatation of the collecting system, 3. small peripheral scar - discrete wedge-shaped parenchymal defects, 4. multiple scars - multifocal or generalized areas of diminished DMSA uptake associated with loss renal cortex. In patients with VUR 99mTc-DMSA renal scintigraphy were detected multiple scars in 53/228 kidneys (23%), small peripheral scar was observed in 34/228 kidneys (15%) and dilatation of the collecting system had 11/228 renal units (5%). In 39/228 renal units (17%) DMSA scintigraphy shows multiple scars in children younger then 6 years. The highest incidence with multiple scars was found in 9 patients with VUR grade V 12/18 renal units (66%). In VUR grade IV incidence of multiple scars was 15/32 (47%) kidneys, in VUR grade III 14/64 (22%) and in VUR I-II 12/104 (11%). In patients without VUR multiple scars was found in 36/284 renal units (12.5%), 46/284 (16%) had small peripheral scar and 9/284 (3%) had dilatation of the collecting system. Multiple scars findings of 99mTc-DMSA renal scintigraphy in patients with VUR was significantly higher, particularly in children with higher grade of VUR, than in patients without VUR (p<0,001). Early identification of VUR and assessment of renal integrity are important in children suffering from UTI in order to prevent reflux nephropathy and ultimately, renal damage. Results of our study confirmed importance of 99mTc-DMSA renal scintigraphy in investigation of children with acute UTI and after UTI.

Mag3 diuretic scintigraphy (f+30) in evaluation of prenatally diagnosed dilated upper urinary tract in newborns

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S. Grbac-Ivankovic, N. Girotto, A. Smokvina; Clinical hospital center Rijeka, Rijeka, Croatia.

Hepatic extraction fraction as a prognostic factor after Kasai hepatoportoenterostomy in infants with biliary atresia

The aim of this study was to assess the role of 99mTc MAG3 diuretic scintigraphy (F+30) in evaluation and follow up of congenital hydronephrosis. Patients and methods:Thirty two newborns (26 males, 6 females), mean age 37 days (range 9 - 134 days), with prenatally diagnosed dilated upper urinary tract on sonography, were included in study. In twenty two changes were located unilaterally and ten had both sides affected. A weight adjusted dose of 99mTc MAG3 was administered iv and 30 minutes later (F+30) 1 mg/kg of furosemide, with total study duration of 45 minutes. Thirteen patients returned for follow up, five of them after surgical treatement.Results: All the hydronephrotic renal units diagnosed with prenatal sonography (N=42), were identified on MAG3 scintigraphy, except four already non-functioning kidneys which showed no tracer accumulation. Of 38 remaining units, according to diuretic responses, 23 (61%) were classified as non obstructed, 10 (26%) as equivocal and 5 (13%) were obstructed. On follow up, 13 of 38 initially hydronephrotic renal units were reevaluated. Five of them were operated on and showed substantially improved drainage on second MAG3 scintigraphy. Of remaining 8 units, six dilated units spontaneously improved, other two showed good diuretic response. There were no renal units with worsening of hydronephrosis or drainage in comparison with initial MAG3 study.Conclusions: All prenatally detected hydronephroses were confirmed with MAG3 scintigraphy. In newborns, an adequate MAG3 uptake and diuretic response can be obtained. F+30 algorhythm allows for spontaneous drainage to be assessed before the diuretic stimulus, in the same time enabling estimation of diuretic response in next 15 minutes. Therefore, in order to estimate clinical significance of prenatally dilated urinary tract and identify patients suitable for surgical treatement, MAG3 diuretic scintigram should be included in diagnostic algorhythm in first months of life.

A. KamiĔska, J. Pawáowska, P. Czubkowski, I. CharzyĔska, E. ĝwiątekRawa, M. Szymczak; The Children's Memorial Health Institute, Warsaw, Poland.

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P589

Value of dmsa scintigraphy in early detection and fallow up of renal parenchyma damage in patients with spina bifida

“The value of cholescintigraphy for diagnosis of extrahepatic choledochal cysts in children and their monitoring after surgery treatment”

S. S. cerci, M. Yildiz, F. Oktem, I. Buyukyavuz, M. Ozbek, H. Suslu, S. Saglam; S.D. University, Medical Faculty, Isparta, Turkey. Objective: Spina Bifida (SB) is the most common of a group of birth defects, which affect the central nervous system (brain and spinal cord). The incomplete innervation’s of the urinary

Hepatobiliary scintigraphy is routinely used method in differential diagnosis of neonatal cholestasis, with high accuracy in ruling out biliary atresia when intestinal bile flow is not disturbed. Some papers revealed that hepatic extraction fraction (HEF), as a measure of the hepatocyte efficiency in eliminating the radiopharmaceutical from blood, may play role as a prognostic factor in after hepatoportoenterostomy follow-up in infants with biliary atresia. It has been recently reported that low value of HEF correlated with poor prognosis and likewise normal value of HEF (>90%) indicated a favourable outcome after Kasai operation. The aim of the study was to investigate the prognostic value of HEF by employing deconvolution analysis during routine hepatobiliary scintigraphy in newborns with biliary atresia. Materiala and methods: A retrospective analysis was performed in 34 infants with surgically proved biliary atresia. During diagnosis every child underwent the hepatobiliary scan after intravenous, bolus injection of 99mTc-MBrIDA with assessment of hepatic extraction fraction by deconvolution analysis.The mean age of infants was 40,8 days (from 14 to 76 days)Results: Kasai operation was followed by liver transplantation in 18 infants due to chronic liver failure: in 12 children HEF was <90% during diagnosis and in 6 infants HEF was >90%. Up-to-date 16 infants haven’t required liver transplantation. In this group 7 of them presented with HEF <90% and 9 with HEF > 90%.Conclusions: The study didn’t reveal significant correlation between value of HEF during diagnosis and prognosis after Kasai operation what is different with previously reported data.

E. Swiatek-Rawa, A. Kaminski, A. Kaminska; Center, Warsaw, Poland.

Memorial Child Health

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Poster Presentation

pathologies, 9%. While 55% of the cases were managed conservatively, remaining 45% underwent surgical intervention. Pyeloplasty was performed in 23%, ureteroneocystostomy in 7%, nephrectomy in 7%, urethral valve ablation in 4%, and other surgical interventions in 3% of the patients. Initially, while mean ipsilateral differential renal function (DRF) was 46%±8% in conservatively treated group, it was 51%±12% at the end of follow-up period. In pyeloplasty group, mean ipsilateral DRF values were 35%±13%, 49%±14%,before and after surgery, respectively. Mean ipsilateral DRF was 14%±15% in the patients who underwent surgery other than pyeloplasty and it was 21%±12% after the surgical interventions. Conclusion: Our algoritm might be safely used in conservatively follow-up of the patients with hydronephrosis diagnosed at antenatal period and UPJ obstruction requiring pyeloplasty. However, its use in hydronephrosis which caused by the pathologies other than UPJ obstruction should be reevaluated.

Choledochal cysts are uncommon anomalies of the biliary tract in children. The etiology of this phenomenon is unknown. Pathophysiology consist of hepatic cirrhosis, pancreatitis, bile duct carcinomas. Usualy symptoms of pancreatitis, ascending cholangitis are developed before age 2. Total excision of extrahepatic choledochal cyst is the only accepted method of treatment. Postoperative complication included: bile leaking, anastomotic stricture, hepatic failure. TheAim The assesment of cholescintygraphy sensivity for diagnosis of choledochal cyst. Usefulness of cholescintigraphy for diagnosis of extrahepatic choledochal cysts. Usefulness of cholescintigraphy for monitoring after surgery treatment. The place of cholescintigraphy in diagnostic - treatment algorytm in children with extrahepatic choledochal cysts. Material In the period of 20 years 68 children aged from 2 month to 14 years who underwent excision of choledochal cysts, underwent cholescintigraphy before and after operation. Method The qualitative cholescintigraphy estimating of liver uptake, the morfology of biliary tract and bile flow was performed before and after operation. Results of cholescintigraphy were compared to clinical presentation, usg, serum bilirubin level, histopathology, surgically proven existence and type of the extrahepatic choledochal cysts. Statistical analisis was performed using Fisher, Ch2, Kruskal Wallis,t test.P< 0,05 was estimated as a significant. Results The sensivity of cholescintigraphy and usg for diagnosis of choledochal cyst were 92,6%, 87% respectively. The positive correlation of scintigraphic liver uptake to serum bilirubin level <1 was 92%. The positive correlation of scintigraphic liver uptake to histopathology of liver biopsy was 92%. The scintigraphy evaluation of liver uptake before and after operation revealed: improvement in 17,5% and worsening in 1,5% of patients. The dilatation of intrahepatic biliary tree estimated on scintigraphy before and after operation improved 44% and worsen in 3% of patients. The scintigraphy estimation of bile flow over Roux -Y loop were correct in 81% of patients, slower in 17,5%, obstructed in 1,5%. Conclusions Cholescintigraphy is very sensitive for evaluation of biliary tract diseases and shoud be performed in all patients suspected of liver and biliary tract anomalies. There is good correlation between cholescintigraphy, usg, serum bilirubin level and histopathology examination. Cholescintigraphy is useful to monotoring operation effects estimating liver uptake, imaging of biliary tree and bile flow before and after total excision extrahepatic choledochal cyst. Cholescintigraphy is useful in monitoring short and long term outcome after surgery for choledochal cysts and should be performed 6 months after operation and always when biliary tract complication is suspected.

elevated TSH levels or were treated because of CH in pediatric endocrinology department between October 2004 and March 2005,were enrolled in this study in order to establish the etiology of CH. All the patients underwent thyroid function tests (TSH,fT4) and thyroid scintigraphy(TS).The number of patient whom gray ultrasonography(GSU) and color Doppler ultrasonography(CDU)applied,were 155 and 122,respectively.122 patients perclorate discharge test(PDT) and 52patients underwent urine iodine test(UIT). RESULTS:In cases diagnosed as PCH via nuclear medicine techniques and ultrasonography fT4 levels were 8,2±7,5pmol/L and TSH concentrations were 175±244,2mIU/L.The values of fT4 and TSH in TCH were 12,4±7,2pmol/L, 7,38±3,45mIU/L,respectively.GSU revealed 23 aplasia,22 hypoplasia,2 diffuse hyperplasia, and 108 normal gland localization out of 155 patients.No ectopy were shown.TS was applied to 194 patients. Out of 194 patients 25had aplasia,32of 194ectopy,29 of 194 had diffuse hyperplasia with increased uptake.108of 194 patients revealed normal thyroid tissue.CDU,determined 21ectopia,11 agenesis,4diffuse hyperplasia,1 thyroiditis,85normal glands in 122patients.CDU,detection sensitivity, specificity,positive and negative predictive values for ectopia were 80%, 98.8 %, 95.3 %, and 94.4 %, respectively. PDT was performed in 122 Patients.The findings were consistent with an organification defect in 42 out of 122 cases.On the basis of both nuclear medicine techniques and USG, patients were finally classified as TCH(92patients,47%) or PCH(102patients,53%).UIT were applied to 52patients with TCH and in 22cases (31%) the concentration were low.The group of PCH were consist of 22(21,5%) agenesis, 32(21,5%) ectopia and 48(47%) dishormonogenesis.After determining of the etiology of CH, the PCH groups were received higher treatment doses for a life time, whereas TCH group had lower treatment doses for a shorter period.CONCLUSION:TS and USG are complemantary tests to clarify the etiology of CH.TS is currently the most precise diagnostic technique to establish the diagnosis of agenesis and ectopia.USG is a noninvasive imaging technique that can be used as a first line image examination for evaluating CH.However, highly radiologist-and equipment-dependent interpretation of USG and difficulty in applying to neonates lowers the sensitivity,compared to TS.

P48 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Nephrology & Urology

P590 Comparison of bone scan and MIBG scan in the evaluation of patients of stage IV neuroblastoma 1

2

1

1

G. Meristoudis , V. Papadakis , C. Batsakis , A. Tsaroucha , V. Giannakopoulos1, S. Polychronopoulou2, A. Paisiou2, T. Liotsou1, J. Christacopoulou1; 1Dept of Nuclear Medicine, “Sotiria” Hospital, Athens, Greece, 2Dept of Pediatric Hematology, “Aghia Sophia” Children Hospital, Athens, Greece. Back-ground: Neuroblastoma (NB) is one of the most common malignancies in childhood. Imaging studies, especially bone scan (BS) and MIBG scan (MIBG) are important for staging and assessment of response to therapy particularly in advanced disease (stage IV). Aim of the study was the comparison of utility of BS and MIBG in the detection of osseous lesions in patients with advanced stage of neuroblastoma. Patients and method: Sixteen patients (8 males, 8 females, aged 2 mo - 6 years) with a proven diagnosis of NB according to the international Neuroblastoma Staging System (INSS) criteria, were submitted in 35 BS and MIBG, within an interval period of 2 weeks. MIBG was performed 24 hrs after iv. injection of 3.7 MBq 123I MIBG/kg body weight. Average acquisition counts were 300Kcounts for the head, 500Kcounts for the thorax, abdomen and pelvis and 200 for lower extremities. BS was performed 3 hrs after iv. injection of 7.4 MBq of 99mTcMDP / kgr body weight. Average acquisition counts were 500Kcounts for the axial skeleton and 250Kcounts for the head and extremities. Concurrent hormone levels, bone marrow biopsy and clinical and imaging follow-up served as standard of reference. BS and MIBG were compared with regard to lesion detection and extend of disease; sensitivity and specificity of both tests were calculated.Results: BS and MIBG findings

TP

TN

FP

FN

BS

7

19

2

7

MIBG

13

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0

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P592 Is T½max a useful parameter for estimating renal transit? J. Kuyvenhoven1, A. Scholtens1, A. Piepsz2, H. Ham2; 1Ziekenhuis Gelderse Vallei, Ede, The Netherlands, 2Ghent University Hospital, Ghent, Belgium. Aim: Mean transit time (MTT) obtained by deconvolution is not influenced by the level of overall renal function, contrarily to empirical renogram parameters like T½max, the time at which half of maximum of the down sloping renogram curve occurs. In clinical practice however, the usefulness of T½max has been questioned. This work aims at determining, for a wide range of MTT values and using different input functions, the relationship between MTT and T½max.Materials and Methods: In a simulated acquisition (duration 1800 sec, 720 frames, time/frame 2.5 sec), 10 input functions (plasma disappearance curves of 99mTc-MAG3, renal clearances ranging 33 - 405 ml/min) were convolved with 522 retention functions, characterized by minimal transit time ranging 150 - 720 sec, MTT ranging 160 - 1370 sec and maximal transit time ranging 170 - 1800 sec. MTT was compared to T½max and Tmax for different levels of renal function as expressed by renal clearance. A total of 5220 renograms resulted of which 2985 renograms with T½max (ranging 458 - 1800 sec). For clearances 33, 69, 99, 141, 190, 238, 271, 329, 377 and 405 ml/min, respectively 0, 38, 325, 365, 313, 310, 377, 437, 355, and 465 renograms with T½max ” 1800 sec resulted. For renograms with T½max ” 1800 sec, mean ± sd of MTT equalled 610 ± 207 sec (range 160 - 1195 sec). Correlations between MTT and T½max, MTT and (T½max - Tmax) for individual clearances ranged respectively 0.82 - 0.93 and 0.49 - 0.69, and were for each individual clearance lower than the correlation between MTT and Tmax (range 0.94 - 0.99). When data were grouped for clearances, the correlations between MTT and Tmax, MTT and T½max and between MTT and (T½max - Tmax) were respectively 0.99, 035 and 0.00 (n = 363) for low clearances (< 100 ml/min), 0.97, 0.78 and 0.35 (n = 1365) for intermediate clearances (100 - 300 ml/min) and 0.98, 0.91 and 0.66 (n = 437) for normal clearances (> 300 ml/min).Conclusions: T½max is not a useful parameter for estimating renal transit. Whatever the level of overall renal clearance, Tmax is a better reflection of the true mean transit time.

P593 TP - True positive; TN - True Negative; FP - False Positive; FN - False Negative

Calculated sensitivity and specificity for MIBG and BS was 81%, 100% and 50% , 90% respectively. Among the five cases with concordant true positive MIBG and BS studies, MIBG showed more extensive disease than BS in two, same extent in other two and less extent in one case. Of the three cases with false negative MIBG, two had true positive BS. These cases did not respond to chemotherapy and subsequently died.Conclusions: In patients with stage IV NB, MIBG is more sensitive than BS. However BS is a valuable complement to MIBG in the follow-up of clinically non responding patients with unfavorable histology. In these cases it is suggested that first examination should be an MIBG scan and if it is negative , be followed by a BS.

P591 The role of ultrasonographic and scintigraphic methods in determining the etiology of congenital hypothyroidism M. Tamam, I. adalet, B. Bakır, C. Turkmen, F. Darendeliler, F. Bas, Y. Sanli, S. Kuyumcu, S. Cantez; Istanbul University, Istanbul, Turkey. AIM:In Congenital Hypothyroidism(CH),determining the etiology and differantiating whether it is transient(TCH) or permanent(PCH), are important factors in the prediction of outcome and treatment schedule.Treatment period depends on the etiology of the disease.Patients with dysplastic thyroid tissue(agenesis,ectopia and dyshormonogenesis) undergo replacement therapy for a longer period but treatment period of patients with TCH is shorter.The aim of this study is to compare the efficiency of ultrasonographic and scintigraphic methods in determining the etiology of CH.METHOD:194 patients(88F,106M,mean age 6,2±4,8) who were found to have

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Relationship between Tmax and parameters of the renal retention function J. Kuyvenhoven1, A. Scholtens1, A. Piepsz2, H. Ham2; 1Ziekenhuis Gelderse Vallei, Ede, The Netherlands, 2Ghent University Hospital, Ghent, Belgium. Aim: Tmax, the time at which the maximum of the renogram curve occurs, is a simple parameter for estimating renal transit. It is usually assumed that Tmax is higher but close to minimal transit time (MinTT). The aim of this work was to verify the above assumption and to assess the relationship between Tmax and various parameters of the retention function.Materials and Methods: In a simulated acquisition (acquisition time 2400 sec, 960 frames, time/frame 2.5 sec.), 10 input functions (plasma disappearance curves of 99mTc-MAG3, renal clearances ranging 33 405 ml/min) were convolved with 522 retention functions (RF), characterized by MinTT ranging 150 - 720 sec, mean transit time (MTT) ranging 160 - 1400 sec and maximal transit time ranging 170 - 2080 sec. Correlations between RF parameters and Tmax were calculated, and between Tmax and the time at which RF reached the value of 0.9, 0.8, 0.7, 0.6, 0.4, 0.3, 0.2, 0.1 (respectively T90, T80, T70, T60, T40, T30, T20, T10).Results: A total of 5220 renograms resulted, Tmax ranging 163 - 1773 sec. For all clearances, the lowest correlation was observed between MinTT and Tmax (r2 = 0.23) and the highest correlation between T40 and Tmax (r2 = 0.83). When data were separated into individual clearances (n = 522 for each clearance), lowest correlation was observed between MinTT and Tmax with r2 ranging 0.15 - 0.46. For each of the individual clearances 33, 69, 99, 141, 190, 238, 271, 329, 377 and 405 ml/min, highest correlation (n = 522 for each clearance) was observed for respectively T10 (r2 = 0.99), T20 (r2 = 0.99), T40 (r2 = 0.99), MTT (r2 = 0.99), T40 (r2 = 0.99), T40 (r2 = 0.99), MTT (r2 = 0.98), T60 (r2 = 0.98), MTT

P594 Technetium -99m DMSA studies in children with primary vesicoureteric reflux L. Jaukovic1, B. Ajdinovic1, Z. Krstic2, M. Dopudja1; 1Institute of Nuclear Medicine, Belgrade, Serbia and Montenegro, 2University Pediatric Clinic, Belgrade, Serbia and Montenegro. Prenatal or early antenatal pelvic renal dilatation may suggest vesicoureteral reflux (VUR) and renal parenchimal damage. AIM of this study was to evaluate the relation between the pattern of Tc-99m DMSA renal scintigraphy findings and the results of micturating cystoureterography (MCU) in children with primary VUR. METHODS A standard Tc-99m DMSA protocol was used to study 19 children aged from birth to 12 years ( 14 males mean age of 2.3 years and 5 females mean age 9.2 years). Findings were classified according to the image appearance and relative function of each kidney. MCU was performed in all patients prior to DMSA study, revealing bilateral VUR in 6 patients and unilateral VUR in 13 patients, for a total of 25 refluxing renal units (RRU). High grade of VUR (IV,V) was observed is 13 RRU and low grade (I-III) VUR in 12 RRU. RESULTS Abnormal DMSA scans (defined as focal / multifocal defects or relative renal uptake less than 42% ) were found in 19/25 RRU, normal images in four RRU and equivocal in two RRU. Out of 19 abnormal DMSA scans, 14 scans (74%) showed diffusely decreased tracer uptake, related to reduced kidney size in 10/14 scans. In 79% of cases, this image was seen in males with VUR grade IV and V. Definitive renal scarring was found in 16% of abnormal findings, 10% of abnormal scans were suspected for scarring. CONCLUSION Renal damage on Tc-DMSA scanning in our group of patients was predominantly a pattern of diffusely reduced parenchimal function associated with the presence of VUR of high grade.

P595 Renal scintigraphy versus ultrasonography in diagnosing chronic allograft nephropathy A. Aktas1, M. Aras1, I. Isıklar2, A. Gencoglu1, M. Haberal2; 1Baskent University, Faculty of Medicine, Department of Nuclear Medicine, Ankara, Turkey, 2Baskent University, Ankara, Turkey. Objective: Renal scintigraphy with Tc-99m labelled agents and ultrasonography with or without Doppler Imaging are commonly used diagnostic procedures during the early posttransplantation period. The aim of this study was to compare diagnostic utility of Tc-99m DTPA renal scintigraphy and gray scale/doppler ultrasonography in the diagnosis of chronic allograft nephropathy.Methods: This study included 63 patients with biopsy proven chronic allograft nephropathy. Renal scintigraphy was performed using Tc-99m DTPA. Images were acquired every second during the first minute and then every 30 seconds during 20 minutes. The following parameters were computed: the ratio of peak counts to plateau counts (P:PL) during perfusion, glomerular filtration rate (GFR), and residual cortical retention of activity at the end of the study (R20/3). On ultrasonography, parenchymal echogenicity was graded and resistive indices in the renal artery and its branches were calculated.Results: Perfusion was impaired in 60 recipients (95%) on renal scintigraphy. Increased resistance indices were detected in 45 patients (71%) on Doppler sonography. Increased echogenicity was observed in 42 recipients (67%) on gray-scale ultrasonography evaluation. Glomerular filtration rate was impaired in 61 patients (97%) and there was increased residual cortical retention in all patients.Conclusions: The sensitivity of perfusion evaluation using renal scintigraphy appeared to be significantly higher than doppler sonography in the diagnosis of chronic allographt nephropathy. Perfusion and parenchymal evaluation was equally sensitive on renal scintigraphy. Parenchymal indices of renal scintigraphy seem to be more sensitive than echogenicity changes on ultrasonography.

P596 Diagnosis of leaks in the peritoneal cavity in patients undergoing dialysis by peritoneal scintigraphy. Our experience between 2000 and 2006 P. Paredes Rodríguez, M. Rioja Martín, L. Díez Jiménez, I. Santos Gómez, N. Rodríguez Mendiola, Á. Crespo Díez; Hospital Ramón y Cajal, Madrid, Spain. Near to 5% of peritoneal dialysis patients show leaks in the peritoneal cavity of the dialisis solution. The peritoneal dialysis must end in many occasions as a result of this complication Objective The aim of this retrospective study was to show our experience in this modality for the diagnosis of abdominal cavity defects in peritoneal dialisis patients, and to evaluate the most frequent locations and the number of scintigraphies with no leak detection. Materials & Methods Thirteen patients were included in this study. There were 2 females and 11 males, with an age range between 28 to 69 years, who presented pleural effusion (6 cases), scrotal edema (3 cases), and 4 cases suspected to have dialysate leakage via abdominal wall defect. Peritoneal scintigraphy was performed after administration of 74 MBq (2 mCi) of Tc99m-Fitate in 2 liters of dialisis solution during 20 minutes approximately. The patient was encouraged to remain mobile to enhance leak detection. Imaging was performed into 30 minutes and 2 hours, in the most suitable views. The dialysate fluid was drained from the peritoneal cavity and another scan was performed then. Results Scintigraphy revealed a leakage into the scrotum in 3 patients, periumbilical leakage in 4 cases, and peritoneopleural communication was demostrated in 1 patient, in the other 5 patients the pleural effusion had different production mechanisms. Conclusion Peritoneal scintigraphy is a highly sensitive, non-invasive, low radiation, simple, safe and convenient procedure with diagnostic value in evaluating dialysate leakage encountered in patients on continuous ambulatory peritoneal dialisis.

P597 Comparison of Tc99m DMSA scintigraphy findings in between children with or without VUR (vesicourethal reflux) R. Orak, G. Koca, E. Özdemir, K. Demirel, S. Türkölmez, M. Korkmaz; Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey. Aim: The most significant result of VUR is moving of infected urine from bladder to kidneys and causing permanent damages on kidney parencyhmas through intrarenal reflux. We evaluated renal parenchyma damage development on VUR positive and negative children with Tc-99m DMSA scintigraphy in this study.Materials and Methods: The study was performed in 103 pediatric age group patients (71 f/ 32 m, with an age mean of 6.1±3.4, min:1, max:13 years ) who were refered to our clinic for VUR evaluation. Seventy-four patients underwent Indirect Radionuclide Sistography (IRNS ) and 29 patients underwent Direct Radionuclide Sistography (DRNS). All those patients were evaluated with Tc-99m DMSA scintigraphy and renal ultrasonagraphy (US).Results: Among patients who were evaluated with Radionuclide Sistography, 32 (31.1%) were found to have VUR ( %; 26 patient IRNS, 6 DRNS). During VUR evaluation, grade 1 reflux for 18 patients, grade 2 reflux for 7 patients, grade 3 reflux for 5 patients, and grade 4 reflux for 2 patients were dedected. 4/32 (12.5%) patient had bilateral VUR. Tc99m DMSA was normal in 84 (81.6%) patients and abnormal in 19 (18.4%) patients. When RNS and Tc99m-DMSA findings were compared, there were 57 patients (55.3%) normal and 5 patients (4.9%) abnormal in both modalities. In 14 patients (13.6%) RNS was normal while Tc99m-DMSA was abnormal and there were 27 patients (26.2%) vice versa. US findings were abnormal in 32 (31.1%) patients. Pearson Chi-Square Test failed to differantiate any statitical differences for parenchyma pathology between VUR (+) and (-) cases (p > 0.05).Conclusions: Since there is no statitically significant differences in our study for renal parenchyma damage risk between VUR positivity and negativity and as their findings are complimentary, Tc99m DMSA and renal US have to applied together in children with urinary tract infection even VUR is negative.

P598 Scintigraphic evaluation of testicular uptake for the outcome of laparoscopic vein ligation in primary varicocele A. M. E. Fawzy1, F. Bassiouny2, H. Amer2, A. Shahry2; 1Nuclear Medicine, Kasr El Aini Hospital, Cairo University, Cairo, Egypt, 2Surgical Department, Kasr El Aini Hospital, Cairo University, Cairo, Egypt. Introduction The methods used for evaluation of testicular vascularity was duplex evaluation and Tc-99m testicular uptake which reflects the more important quantitative physiologic parameters of blood flow, rather than the morphologic (size of the spermatic veins) or qualitative physiologic parameter of reflux offered by duplex assessment. Aim: To test the reproducibility of Tc-99m testicular uptake as a quantitative assessment of vascularity of different laparoscopic ligational modalities rather than the qualitative assessment offered by Duplex studies. And also to evaluate the difference between simultaneous ligation of the internal & external spermatic veins & the classical procedure.Methods: The combined static & dynamic Tc-99m testicular uptake was used to quantitate circumoperative changes of testicular blood flow in 21 consecutive patients complaining of primary varicocele. Clinical history and assessment were performed. However, The main inclusion criterion for patients in the present study was their duplex findings rather than their symptoms. Preoperative investigation included semen analysis, duplex study and scrotal scintigraphy using free technetium These patients were randomly allocated depending on the procedure done: internal spermatic vein ligation only (group A) and simultaneous ligation of internal and external spermatic veins (group B) Results There was no statistically significant difference in the mean age, duration of complaint, clinical presentation, bilateral presentation and seminal parameters between both groups. There was no statistically significant difference in the preoperative mean right or left testicular Tc-99m uptake or the mean ratio of right to left testicular uptake in the two groups. In unilateral cases in both groups, there was a statistically significant increase in Tc-99m uptake in the left testes relative to their right ( P=0.0001 ). One month postoperative duplex assessment revealed the absence of detectable reflux in the spermatic cord vessels on the clinically affected side in all the cases. There was no statistically significant difference in the postoperative mean left or right testicular uptake in both groups. There was no statistically significant difference in the postoperative mean right testicular Tc99m- uptake in the unilateral cases in the two groups. Comparing preoperative to postoperative Tc99m- uptake on the left side showed a statistically significant decrease in Tc99m- uptake on the left side following laparoscopic varicocelectomy in both groups.Conclusions: Implementation of Tc-99m uptake is a reproducible & useful quantitative investigation of vascularity of the testes in primary varicocele patients. It may be used for postoperative follow up & possibly preoperative categorization of patients.

P599 Renal scintigraphy in evaluation of kidney functions in patients with liver cirrhosis A. M. Fawzy1, T. A. F. El-Maghraby2, A. Musaad3; 1Cairo University, Cairo, Egypt, Fahd Specialist Hospital, AD-Dammam, Saudi Arabia, 2Cairo University, Cairo, Egypt, Saad Specialist Hospital, Al-Khobar, Saudi Arabia, 3 Internal Medicine, Cairo University, Cairo, Egypt. Patients with advanced liver cirrhosis often develop a peculiar form of renal failure without apparent clinical, laboratory or histological features of renal dysfunction. This is known as hepato-renal syndrome. The aim is to evaluate the role of isotopic renography for the early assessment of renal changes in patients with liver cirrhosis for proper early diagnosis and management.Materials and Methods: 21 patients (6 females & 15 males) aging 51.2+11.2 Y and 7 controls (age & sex matched) were included. All patients had complete clinical, laboratory and ultrasonographic examination. All of patients were Hepatitis-C +ve & Hepatitis-B -ve with no evidence of diabetes mellitus in all. Liver cirrhosis by clinical examination was present in all and was confirmed by ultrasound. 99mTc- DTPA dynamic renography was acquired in all patients and controls.Results: Eight patients showed normal sized liver (38.1%), 11 had shrunken liver

S345

Poster Presentation

(r2 = 0.98), and T60 (r2 = 0.99). When data were grouped for clearances, the highest correlation was observed between Tmax and T20 (r2 = 0.88, n = 1566) for low clearances (< 100 ml/min), Tmax and T40 (r2 = 0.97, n = 2088) for intermediate clearances (100 - 300 ml/min) and Tmax and MTT (r2 = 0.93, n = 1566) for normal clearances (> 300 ml/min).Conclusions: The assumption that Tmax reflects MinTT is not valid. With decreasing clearance, there is a tendency that Tmax correlates fairly with a parameter of the tail of the retention function, being T40 for intermediate clearances and T20 for low clearances.

(52.4%) and 2 were enlarged (9.5%). Splenomegaly was noted in 19/21 (90.5%), while ascites was observed in 10/21 (47.6%). All patients showed normal kidneys configuration by U/S. Total bilirubin was raised in all patients (2.15±2.0 mg/dL), and the direct bilirubin was 1.01±1.11 mg/dL. ALT, AST and ALP levels were 33.6±20 IU/L; 53.3±27.7 IU/L & 239.4±84.6 IU/L respectively. Total proteins were normal (7.12±1.3 g/dL), while there was definite hypoalbuminemia (2.67±0.5 g/dL). Kidney evaluation revealed normal urea and Creatinine levels (36.1±15.6mg/dL & 0.83±0.22mg/dL respectively), while the Creatinine clearance was slightly elevated (133.55±236.01mL/min/1.73m2). The potassium level was within normal limits (4.01±0.6mEq/L). On evaluating renal scintigraphic parameters in both patients & controls, it was seen that there was no marked difference between the right and left kidneys in all of them. In cirrhotic patients, T-max for right & left kidneys were (7.4±3.2min. & 7.73±3.8 min. respectively) that were significantly delayed compared to controls (4.1±4.7 min. & 2.9±3.9 min. respectively), (P= 0.04 and 0.009 respectively). The right, left and total GFR in the patients were 38.6±15.1, 41.7±19.3 and 76.7±26.4 ml/min respectively, while in the controls were 57.8±14.3, 59.4±20.3 and 117.1±34.3 ml/min respectively. The GFR difference between both groups was statistically significant (P= 0.007, 0.04 and 0.003 respectively)Conclusions: Scintigraphic evaluation of the kidneys is a valid early marker of renal involvement in patients with liver cirrhosis, which could help to start early management and delay the onset of renal failure.

from each DMSA study by using the geometric mean method. Results: Considering all the patients, the values of mean DRF on both before and after diuretic DMSA images were 38.89%±12.89% and 38.71%±12.76%, respectively. There were no significant differences between DRF values of each kidney obtained by 2 methods(P=0.35). When we compared DRF values obtained from standard and from diuretic DMSA studies, the mean of the differences was only 0.18% and the SD was only 1.09%. In 17 patients (group1), diuresis renography revealed an obstructive curve pattern while 16 (group 2) patients had a nonobstructive dilated renogram curve pattern. There were again no significant differences between DRF values obtained before and after diuretic injection in each group. In group 1, the values of mean DRF on standard and diuretic images were 33.97%±10.69% and 33.91%±10.62% respectively, and in group 2, the values of mean DRF were 44.15% ±13.25% and 43.81% ± 13.16%, respectively. Conclusion: Our results demonstrated that in contrast to guideline recommendations, diuretic administration seems to be an unnecessary intervention because it has no effect on the accuracy of DRF measurements using 99mTc-DMSA scintigraphy in patients with a dilated collecting system whether it is obstructed or not.

P603 Vascular peak pattern discriminates normal and severly decreased glomerular filtration function

P600 Comparison of intravenous and oral diuretic administration in renal scintigraphy S. Turkolmez, M. Korkmaz, D. Cayir, G. Koca, E. Ozdemir, K. Demirel; Ankara Training and Research Hospital, Ankara, Turkey. Aim: Diuresis renography is a widely accepted test to differentiate a true obstruction from nonobstructive dilatation. In the standard diuretic renography protocols diuretic is injected intravenously. In the present study, we compared intravenous (F+20) and oral administration (Foral) of the diuretic in cases with upper urinary tract dilatation.Materials and Methods: Twentynine adult patients (41 kidneys) with upper urinary tract dilatation were studied. The mean age was 34.96±11.91 year (range, 18-61 years). The two diuresis renography protocols (F+20 and Foral) were performed to all patients. The results were classified as nonobstructive and obstructive according to the renogram images and curves.Results: Thirteen of the 41 kidneys were evaluated as obstructive in the F+20 study. All of the kidneys showing obstructive patterns in the F+20 study also revealed obstruction in the F-oral diuresis renography. Of the 28 kidneys which were evaluated as nonobstructive in both F+20 and F-oral studies, 12 kidneys showed normal renogram pattern with F-oral investigation. There was statistical difference in Tmax and T1/2 values in kidneys with nonobstructive dilatation with two different protocols. Conclusion: We could not find any difference between the F+20 and F-oral diuresis renography studies in the differentiation of obstructive/nonobstructive dilatation. In the evaluation of patients suspected of nonobstructive dilatation, F-oral study may be used to optimize quantitative renal parameters.

P601 Radionuclide evaluation of radiocontrast-induced nephropathy in patients undergoing coronary procedures Y. B. Lishmanov, Z. V. Vesnina, S. G. Goltsov, A. M. Gulyaev; Institute of Cardiology, Tomsk, Russian Federation. PURPOSE: Using radionuclide renoscintigraphy to study radiocontrast media-induced renal dysfunction in patients undergoing coronary angiography.Materials and Methods: Radionuclide renography with 99mTc-DTPA was used to examine forty seven patients (average age 54.2 ± 1.2 years) before and 2-3 days after coronary angiography (CAG). As radiocontrasts was used Iohexol (15 pts, group I), Iobitridole (18 pts, group II) and Ioxitalamate (14 pts, group III). Filtration and excretory renal functions, including glomerular filtration rate (GFR), blood clearance, parenchymal and collecting system clearance of 99mTc-DTPA were estimated.Results: Kidney functional activity after CAG was not change in 4 pts of the group I (27%), in 5 pts of the group II (28%) and in 4 pts of the group III (29%). Disturbances of excretory function were note in 8 pts of the group I, in 8 pts of the group II and in 6 pts of the group III. We observed insignificant evacuatory dysfunction (within the limits of normal) in 13%, 22% and 36% of cases, respectively. The differences of the disorders of the renal excretory function in respect of collecting system among pts of the various groups were not revealed. However parenchymal clearance of 99mTc-DTPA was significant increased in the groups I and II. Hence more significant negative effect of the radiocontrast on the renal excretory activity in pts of the groups I and II was marked. Scintigraphic parameters that define the filtration activity of the renal parenchyma were disorder to a greater or lesser extent in 8 (53%), 10 (56%) and 6 (42%) pts of each group, respectively. The significant or moderate GFR decrease after CAG in 5 pts of the group I, in 6 cases of the group II and in 3 pts of the group III was note (33%, 33% and 21%, respectively). At the same time in the group III the decrease of the total GFR was not significant (p=0.20). CONCLUSON: Our preliminary data point to the less pronounced Ioxitalamate-induced renal dysfunction as compared with Iohexol and Iobitridole.

P602 Diuretic effect on the measurement of differential renal function using Tc99m-DMSA in patients with hydronephrosis V. Dabbagh Kakhki, S. Zakavi, M. Ebrahimi-Rad; Mashhad University of Medical Sciences, Mashhad, Iran (Islamic Republic of).

T. Erselcan1, B. Turgut1, S. Ayan2, Z. Hasbek1, S. Ozdemir1, S. Gul1, A. Ozdal1; 1Cumhuriyet Univ. School of Med., Dept. of Nuclear Medicine, Sivas, Turkey, 2Cumhuriyet Univ. School of Med., Dept. of Urology, Sivas, Turkey. The purpose of the present study was to evaluate vascular peak pattern of a renogram whether there was a relationship with peak parameters and the degree of renal function. Materials and methods; In 45 patients (29 women and 16 men, mean age; 56.0±17.7) with various degree of a renal function, glomerular filtration rate (GFR) was measured by using Tc-99m DTPA and two samples technique. Global GFR range was 1ml/min to 107ml/min. in patients. The dynamic renal scintigraphy with Tc-99m DTPA was also obtained from all of patients in the same day. Dynamic acqusition protocol consisted of two phases; 60x1 second and 29x1min. images. Renogams were created using half semilunar backgroud susbtracted kidney ROI's. Integrals of counts from each upslope and downslope points on the first three minutes of the renogram were calculated. A ratio (Z/D), obtained by using "area under the first upslope peak point (Z)” and "the area under the first downslope (D)" in vascular peak was compared with the single kidney’s GFR (SKGFR) in 89 kidneys of patients. Those were divided into 4 groups according to SKGFR. Group1; SKGFR<10ml/min. (26 patients). Group2; SKGFR=10-20ml/min. (10 patients). Group3; SKGFR=21-30ml/min. (4 patients). Group4; SKGFR>30ml/min. (5 patients). Area of Z and D were also compared with the areas under the curve in functional time intervals of 1.-2. (INT1) and 2.-3.minutes. Results; Group1 consisted of 52 kidneys with the mean SKGFR (±SD)= 4.9±2.2ml/min. The mean SKGFR in Group2 was 13.6±3.1ml/min (n=20). It was 23.9±3.6ml/min (n=7) in Group3 and 41.8±10.7ml/min (n=10) in Group4. The Z/D ratios were; 1.34±1.70, 0.98±1.08, 0.69±0.41 and 0.46±0.63 in groups 1, 2, 3 and 4, respectively. The Z/D ratio of Group4 was significantly different from that of Group1 (p=0.003) and Group2 (p=0.005). However, correlation was waek between SKGFR and the Z/D ratio (r=0.21, p=0.05) in the whole study group. Better correlation was obtained between SKGFR and Z/INT1 ratio (r=0.38, p<0.01). Conclusion; This study shows that the perfusion (vascular) peak pattern seems reflecting the glomerular filtration function. It is possible to discriminate, with the use of Z/D ratio, a normal functional kidney from a kidney that has severly-decreased function, but in cases with moderately decreased kidney function this ratio widely scatters.

P604 Evaluation of renal function in contrast media receiving patients by means of variation in glomerular filtration rate T. Erselcan1, Z. Hasbek, B. Turgut1, I. Tandogan2, C. Gumus3, I. Akkurt4; 1 Cumhuriyet Univ. School of Med., Dept. of Nuclear Medicine, Sivas, Turkey, 2Cumhuriyet Univ. School of Med., Dept of Cardiology, 3Cumhuriyet Univ. School of Med., Dept. of Radiodiagnostic, Sivas, Turkey, 4Cumhuriyet Univ. School of Med., Dept. of Pulmonary Medicine, Sivas, Turkey. Very limited number of study exist assessing glomerular effects of contrast media in humans, realized by measuring glomerular filtration rate (GFR). Instead, creatinine has been used in almost all of the relating studies and contrast media induced nephropathy is defined as increase of serum level of creatinine more than 25% from baseline or rise by 0.5 mg/dl. The aim of the present ongoing study was to evaluation of renal function in contrast media receiving patients by GFR follow-ups. Materials and methods; GFR was measured so far in 27 patients (10 women and 17 men, mean age±SD; 60±13 years) before and after contrast media applications (within 48 hours), either following by cardiac catheterization (18 pts) or radiological examination (9 pts). Tc-99m DTPA and two serum samples technique was used in GFR measurements. A GFR change of ±10% between pre- and post-examination was accepted as within the range of an individual’s daily variation, together with precision error in GFR measurements. Results; GFR did not changed in 11 pts (41%, GroupI), decreased in 7 pts (26%, GroupII) and increased in 9 pts (33%, GroupIII). Amount of contrast media used in GroupI, II and III, were as follows (mean±SD); 88.0±8.2, 89.3±17.4 and 91.1±21.6 ml, respectively. There was no statistically significant difference among groups in volume of administered contrast media (one way ANOVA, p>0.05). Median percent change (post - pre/pre x 100) in serum urea nitrogen (SUN), creatinine and GFR in study groups were; Pre- and post-exam change (%)

99m

It has been suggested that calculation of differential renal function (DRF) using Tc-DMSA may lead to overestimation of the function of an obstructed kidney. Therefore, to overcome this problem, furosemide injection has been proposed by the guidelines .Aim of this study was to evaluate the effect of diuretic administration on the determination of DRF using 99mTc-DMSA scintigraphy in patients with a dilated pelvis. Patients and methods: Thirty three patients, aged from 2 months to 66 years (19.27±20.83 years, 22 males, 11 females), in whom unilateral hydronephrosis had been documented by ultrasonography and diuretic renography were included in the study. Immediately after the standard study, furosemide was injected in all patients, and 30 min later anterior and posterior images were obtained. DRF was calculated for each patient and

S346

SUN

Creatinine

GFR

GroupI

-15.0

0.0

0.1

GroupII

12.5

0.0

-29.3

GroupIII

15.6

-4.2

43.6

Comparison of the above pre- and post-examination parameters revealed that the only significant difference was in GFR values in GroupII and III, as expected. In addition, 25% of creatinine increase was observed in only two patients, one from GroupI and other from GroupIII. None of them developed renal insufficiency (needed dialysis). Conclusion; the preliminary results suggest that the basal renal function (before contrast media application) of a patient seems more important in contrast induced functional changes than the amount of contrast media itself. Also, biochemical parameters (SUN, creatinine) are relatively insensitive to detect functional variations in contrast media application.

gr III

gr IV

P605 Predictors of 51Cr-EDTA measured Glomerular Filtration Rate (GFR) among demographic, somatometric and bioimpedence variables in kidney transplant donor candidates. 1

1

1

1

2

G. Arsos , E. Moralidis , N. Karavida , N. Boussios , G. Myserlis , D. 1 Takoudas2, C. Karakatsanis1; Dept of Nuclear Medicine, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece, 2 Organ Transplantation Clinic, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece. Aim : GFR is expected, in healthy individuals, to bear a close relationship with metabolic rate and hence, with body size. Body surface area (BSA) is widely, but unjustifiably, used as the measure of body size for GFR indexing. Age , sex, serum creatinine, serum albumin and race are also well known co-predictors of GFR, incorporated in various prediction models.Age and sex are also well known co-predictors of GFR, incorporated in various prediction models. Lean body mass (LBM), a more precise measure of metabolically active tissue is expected to predict GFR better than body weight (BW) or BSA. However, substantial interindividual metabolic rate variation may be related to hormonal status (mainly thyroid and adrenal) or even to dietary lifestyle. The aim of the present study was to evaluate the predictive power of BW, BSA, LBM, age and sex alone and combined in multivariate models on GFR in healthy adults. Patients and methods : Seventy healthy, potential kidney donor candidates (27 women), aged 52.8±12.2 years, with BW 75.3±14.3 kg, were submitted to GFR measurement by the 51Cr-EDTA, slopeintercept, two-sample method. Impedance measurement was performed in all, using a Bodystat 1500 MDD (UK) body composition analyzer, through two pairs of self-adhesive electrodes placed on the right hand and foot. LBM (in kg) was calculated using previously validated regression equations. BSA was calculated according the DuBois and DuBois formula. Univariate and multivariate regression analysis was applied to assess the predictive power of the explanatory variables. Results : In the entire population BSA was 1.81±0.20 kg/m2, LBM 49.3±11.4 kg, GFR 95±27 ml/min (90±22 ml/min/1.73 m2) and serum creatinine level 0.91±0.16 mg/dl. In univariate regression analysis BW, BSA and LBM, explained GFR variability by 30, 33 and 42% respectively. Multivariate models including age, sex and BW or BSA or LBM as measure of body size, could explain 56%, 54% and 54% of GFR variability respectively. Conclusion : LBM is the best single predictor of GFR in healthy adults. LBM values, easily calculated by biompedence appears superior to BSA estimations for routine GFR indexing. Noticeably, multivariate models, irrespectively of the variable used as measure of body size, fail to explain more than roughly half of GFR variability. Normal GFR values indexed for actual metabolic rate measurements could be more appropriate for accurate estimation of renal function in potential kidney donors.

No

53

34

19

Mean

89,14

91,29

85,29

SD

25,35

29,69

14,70

No

16

6

10

Mean

80,19

70,20

86,18

SD

22,72

10,91

26,22

Statistical analysis revealed significant differences between all groups in the total population except gr III and gr IV, while in males statistical difference also exists between gr III and IV and in females between gr I and all others groups and between gr II and III. No statistical differences were found between males and females of the same group.Conclusions: There is an inverse correlation between age and GFR while sex doesn’t seem to play a significant role. These results have to be taken into account when establishing reference values for GFR.

P607 Use of diuretic renography in monitoring the upper urinary tract following cystectomy and diverted urinary to the intestine in bladder cancer. n. lopez, T. Cambil, A. Samaniego, p. de la riva, I. Acevedo, C. Calvo; virgen Macarena Hospital, sevilla, Spain. AIM: Enlargement of the upper urinary tract often occurs after cystectomy and intestinal urinary diversion. The early diagnosis of detecting an obstruction is vital to preserve renal function. The objective of this study is to show the efficiency of the Diuretic Renography (DR) in monitoring these patients.Materials and Methods: The study consisted of 46 patients (43 men and 3 women with an average age of 64.5) suffering from bladder cancer whom had cystectomy and intestinal urinary diversion (type Mainzll or Paduana) having 1 - 6 years follow-ups. Prior to surgery they had intravenous urography (IVU). The post-surgery follow-ups included abdominal ultrasound scans, in which if the collecting system was found to be normal, judged with annual IVU, and if found dilated, DR each 6 -12 months and annual IVU. The DR was carried out with 92.5MBq of MAG3 Tc-99m, injecting Frusemide on the 20th minute (F+20), interpreting the morphology of the renogram curves according to O’Reilly Classification and obtaining the relative renal functions. The assessment was done for Renal Unit (RU), differentiating among: Normal Kidney (NK), Non-obstructed or functional Hydronefrosis (HN), obstructed HN, kidney with sever hypo-function or annulment and equivocal. Interpreting the IVU groups, the findings obtained in: normal collecting systems, dilated collecting systems and functional annulment, we compared the results of the different techniques used with the final urology diagnosis. We analysed the repercussions of the different pathologies on individual renal functions.Results: 46 patients (92RU)

Post-surgery

Age as determinant of GFR measured by and females

51

Pre-surgery

Cr-EDTA in males

IVU

J. Koutsikos, H. Fotinaki, G. Papathanasiou, V. Saranti, C. Kardara, C. Zerva, A. Leondi; Department of Nuclear Medicine, Alexandra University Hospital, Athens, Greece. INTRODUCTION: Estimation of the GFR is an essential part of the evaluation of patients with renal disease. An association between age and decreasing GFR has been suggested by several studies. We carried out a retrospective study in order to evaluate the correlation between GFR and age in males and females and establish reference values.Materials and Methods: Among patients, that underwent clinically indicated routine measurement of GFR using 51Cr-EDTA during last 10 years, we studied 239 patients (108 males, 131 females) with normal renal function (serum creatinine measurement within normal range in the 12 months period prior to GFR). These patients were: a) diabetics (type I & II), b) paraplegics, c) renal graft donors and d) presenting microscopic haematuria. A protocol of GFR measurement by 100 µCi (3.7 MBq) of 51 Cr-EDTA injection, three blood samples at 2, 3 and 4 hrs p.i., was performed. Volume of distribution was obtained by extrapolation of the clearance curve to zero time. GFR was scaled to a body surface area of 1.73 m2.Results: Mean (and SD) GFR measurements according to age (4049.99 y.o. [gr I], 50-59.99 y.o. [gr II], 60-69.99 y.o. [gr III] and older than 70 years [gr IV]) are shown in the next table.

Normal urinary tract

67

IVU 30

Dilated urinary tract

19

52

Hypofunction/ annultment.

6

8

RD 25 Non-obstructive

Obstructive

29

14

24

Post surgery: the renography detected an increase of 10% of pathology kidneys than the IVU. 51% presented dilated upper urinary tract. Renography differentiated a 31.5% of non -obstructive HN, which did not vary in this time 15.2% of obstructive HN. In 2 RU the DR showed a wrong response. It detected a 17% increase of sever hypo-function on the renogram which is not detected by the IVU. Of the normal IVU, a 28.5% presented a deterioration of the renal functions. 73.3% of the non - obstruction dilated collecting system, maintained their conserved functions. 65% of the obstructed collecting system presented deterioration of the renal functions.Conclusions: The DR allows us to distinguish the dilated upper urinary tract with obstruction from those with no obstruction and judge individual renal functions, thus saving unnecessary activities not exempt of morbidity.

P608 Total

gr I

gr II

pts Males

Females

(ml/min/1.73m2)

(ml/min/1.73m2)

(ml/min/1.73m2)

No

99

31

68

Mean

117,81

116,52

118,41

SD

25,99

26,03

26,15

No

71

37

34

Mean

103,07

103,53

102,56

SD

24,98

26,25

23,90

The role of TPSA, IGF-1 and IGFBP-3, values in the distinctive diagnosis of benign prostate hyperplasia and prostate cancer. H. Kaya1, I. Sucu1, S. Altun Tuzcu1, S. Ar1, H. Sahin2; 1Dicle University School of Medicine Department of Nuclear Medicine, Diyarbakir, Turkey, 2 Dicle University School of Medicine Department of Urology, Diyarbakir, Turkey. Background and aim: Prostate cancer is the most common cancer in men and is the second, after lung cancer among the cancer related deaths. Although PSA is still the most significant indicator of independent prostate cancer, when IGF-1 is evaluated with PSA, it may increase the predictive value of PSA. In this study we aimed to investigate the role of TPSA, F/TPSA, IGFBP-3, IGF1/TPSA and IGFBP-3/TPSA values in the distinctive diagnosis of benign prostate hyperplasia

S347

Poster Presentation

P606

(BPH) and prostate cancer with or without one metastasis.Materials and Methods: twenty patients with biopsy proven prostate cancer and 26 patient with BPH, totally 46 subjects, were included to the study. Bone scintigraphy of the patient with prostate cancer was performed after 20mCi Tc-99m-MDP administration. FPSA, TPSA, IGF-1 and IGFBP-3 levels of the subjects were measured with radioimmunoassay. Mann-Whitney-U test was used for statistical analysis.Results: Median TPSA level of patients with prostate cancer was higher than BPH group (20.22ng/ml, 1.92ng/ml, p<0.0001). FPSA/TPSA ratio of prostate cancer group was lower than BPH group (0.10ng/ml, 0.21ng/ml, p<0.05). Median IGF-1 levels of patient with prostate cancer was significantly higher than BPH group (234.5ng/ml, 153.5ng/ml, p<0.0001). In contrast, IGFBP-3 levels of prostate cancer group lower than BPH group (1513.5ng/ml , 2405ng/ml, p<0.05). IGF-1/TPSA and IGFBP-3/TPSA ratios of patient with prostate cancer were lower than BPH group (6.67ng/ml and 50.63 ng/ml, 94 ng/ml and 1049 ng/ml, respectively, p<0.0001). TPSA levels of prostate cancer patients with bone metastasis were high (48.88±38.28ng/ml).Conclusions: bone scintigraphy should be recommended especially, prostate cancer patient with high TPSA levels. Serum IGF-1 levels was high and serum IGFBP-3 levesl was low in the patient with prostate cancer. High IGF-1 levels and low IGFBP-3 levels may be risk factors for development of prostate cancer. High IGF-1 levels, low IGFBP-3 levels and low IGF-1/PSA, IGFBP-3/PSA ratios might be new parameters to distinguish prostate cancer and BPH, but further studies are necessary in this field.

P609 Chromogranin a and prostate specific antigen in the diagnosis of prostate cancer patients and benign prostate hyperplasia R. Ruano Perez1, M. Martin Rodriguez1, J. M. Silva Abuin2, J. R. GarciaTalavera1; 1Nuclear Medicine Hospital Universitario., Salamanca, Spain, 2 Urology. Hospital Universitario., Salamanca, Spain. Objective: Chromogranin A (CGA) is a neuroendocrine tumor marker correlated with the neuroendocrine differentiation of the prostate cancer and often associated with a poor prognosis. We considered newly diagnosed prostate cancer and benign prostate hyperplasia (BHP), and determined serum levels of CGA, PSA, freePSA and PAP to evaluate its use in prostate cancer diagnosis in everyday practice.Methods: We included 105 men with newly diagnosed prostate cancer (PC) recruited from the period 2001-2004 and 116 men without any urologic treatment diagnosed as benign prostate hyperplasia (BHP). In all PC cases diagnosis was made by transrectal ultrasound guided biopsy, and in non-malignant cases PC was excluded by digitorectal examination, serum PSA levels or transrectal ultrasound guided biopsy. Serum levels of CGA, PSA, freePSA and PAP were compared between cases and BHP.Results: Serum PSAlevels were significant higher in PC cases (21,8+ 8,4 ng/ml, mean+ standard error of the mean) than in BPH (9,96+12,1ng/ml).%freePSA/tPSA was significantly different in PC cancer than BPH (16,94 vs 22,31, p=0.000), and PAP also was significant higher in PC cases (9,22 vs 4,54 ng/ml, p=0.005). In contrast, serum CGA was slightly higher in PC cases (97,74 + 77,4 ng/ml) than BHP cases (92,04 + 12,8 ng/ml) but we found no significant differences when compared both groups (p=0.167). CGA did not show correlation with the other serum markers PSA, PAP, nor with age, digito-rectal volume, or Gleason score.Conclusions: According to our data the determination of CGA serum levels adds no more information in the diagnosis of prostate cancer in everyday clinical practice.

P610 99m

99m

Tc-EC vs. Tc-MAG3: A comparative study of two radiopharmaceuticals for renal function assessment

D. Beiki1, M. Eftekhari1, B. Fallahi1, F. Gheisari2, M. Hojabrossadat1, A. Fard-Esfahani1, K. Ansari-Gilani1; 1Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of), 2 Shiraz University of Medical Sciences, Shiraz, Iran (Islamic Republic of). Aim: 99mTc-Mercaptoacetyltriglycine (MAG3) is a renal tubular radiopharmaceutical which has been introduced for dynamic renal study (DRS) and measuring effective renal plasma flow. Despite the excellent imaging properties, it has numerous technical limitations such as radiopharmaceutical impurities, instability, high hepatic uptake and requirement for boiling in 100°C water. 99mTc- ethylenedicysteine (EC) is also a tubular radiotracer which has not such limitations. This study was designed to compare 99mTc-EC with 99mTc-MAG3 in assessment of different aspects of renal function.Materials and Methods: Forty two patients (23 male, 19 female, 34±11.2 years) with normal serum creatinine entered this prospective study. All patients were hydrated with 10 ml/kg of water prior to the studies. For each patient DRS with i.v. injection of 370 MBq 99mTc-EC was carried out in supine position with serial standard imaging up to 30 minutes. Seven days later DRS was repeated with 370 MBq 99mTc-MAG3 using the same protocol. The renograms were obtained and renal functional parameters such as differential renal uptake, differential parenchymal transit time, time to peak activity and effective renal plasma flow (ERPF) as well as hepatic uptake were calculated using special formulae and computer softwares.Results: The renogram pattern was identical for both radiotracers. Renal uptake values for 99mTc-EC had significant correlation with the values of 99mTc-MAG3 (r=0.779, p=0.0001), however; mean uptake value for 99mTc-EC was significantly higher than that of 99mTc-MAG3 (6.3% vs. 4.55%, p=0.0001), while mean transit time of the kidneys for 99mTc-EC showed no significant difference with the values of 99mTc-MAG3 (3.76±1.87 min vs. 3.65±2.3 min, p=0.453). Also mean hepatic activity of 99mTc-MAG3, 409 maximum count per pixel (mcpp) was significantly greater than 99mTc-EC, 291 mcpp (p<0.0001), while the background activity was the same. Lastly the mean effective renal plasma flow (ERPF) calculated with 99mTc-EC, 312 ml/min, was more than that of 99mTc-MAG3, 232 ml/min (p=0.0001), however; good correlation was noted between the values of two studies (r=0.899, p=0.0001).Conclusions: The calculated ERPF and renal uptake values with 99mTc-EC have good correlation with that of 99mTc-MAG3. Thus the advantageous properties of 99mTc-EC (easier preparation, more stability, more renal uptake, less hepatobiliary activity and rapid transit time) make it an appropriate or even preferred radiopharmaceutical for renal function studies in comparison with 99mTc-MAG3 .

P611 Separated evaluation of the renal function in patients performed double renal transplant in mono or bilateral site A. Niccoli Asabella1, N. Merenda1, F. Iuele1, L. Garofalo2, P. Ditonno2, D. Rubini1, M. Pisciotta1, G. Rubini1; 1Dept. Nuclear Medicine, University of Bari - Italy, Bari, Italy, 2Dept. of Urology, University of Bari - Italy, Bari, Italy. Aim Aim of the study is to evaluate the role of the Dynamic Renal Angioscintigraphy and the nephrogram analysis in adult patients performed simultaneous double renal transplant (SDRT) in mono or bilateral site. Materials and methods 16 adult patients underwent monolateral or bilateral SDRT have been enrolled: • 11 monolateral (retroperitoneal in iliac fossa) • 5 bilateral. The Dynamic Renal Angioscintigraphy was executed in the successive period to the transplant (range 1 day - 18 months). 148 MBq of 99 mTc-MAG3 were injected in bolus. Dynamic acquisition in antero-posterior projection was performed with Infinia gamma camera (GE Medical) with patient in supine position Results Monolateral SDRT In the patients underwent monolaterale SDRT with renal stasis or hydroureteronephrosis of the kidney situated inferiorly, the evaluation of the superiorly localized kidney was partially compromised (patients n. 1 - 4 - 6 - 11). The Dynamic Renal Angioscintigraphy has permitted to recognize a normal post-transplant recovery (patient n. 3) and the following pathologies: • acute reject (patient n. 5) • renal stasis (patients n. 1 - 4 - 7 - 11) • Hydroureteronephrosis (patient n. 6) • Renal dysfunction and delayed functional resumption (patient n. 2). Bilateral SDRT The Transit Mean Time (TMT) entered into the normality values, except in patient n. 14. It was possible to obtain value of Tubular Excretion Rate (TER) with results very similar to those of normal subjects. The relative functional contribution of transplanted kidneys was symmetrically shared. The Dynamic Renal Angioscintigraphy has shown normal post-transplant recovery in patient n. 15 and renal stasis in 4 patients (n. 12 - 13 - 14 -16). Conclusions The Dynamic Renal Angioscintigraphy permits to estimate in separated way, the perfusion phase, function and excretive phase of two transplanted kidneys, either in emergency conditions, or during follow up. It can monitor the renal function and find out the eventual complicances that can interest single kidneys, also in patients with conserved renal functionality. The Dynamic Renal Angioscintigraphy and the study of the radionefrographic curves in monolateral or bilateral SDRT are conditioned by the kidneys position in bilateral or monolateral site. In the SDRT in the monolaterale site constantly there is a partial over imposition of kidneys. Finally it was observed that the ERPF value change in relation to the depth of kidneys, in particular in double monolateral the renal transplant.

P612 Interobserver reproducibility of a PC-compatible software to standardize the lasix renography I. Roca Bielsa1, S. Bouyoucef2, H. Rajabi3, R. Kumar4, N. Aalvarado5, P. Bernal6, L. Kaliska7, S. Nazarenko8, P. Orellana9, H. Posada6, S. Saeed10, L. Si-Jin11, A. Padhy12, M. Zaknun12, M. Dondi12; 1Hu Vall Hebron, Barcelona, Spain, 2IAEA, Alger, Algeria, 3IAEA, Teheran, Iran (Islamic Republic of), 4IAEA, Delhi, India, 5IAEA, Lima, Peru, 6IAEA, Bogota, Colombia, 7IAEA, Slovakia, Slovakia, 8IAEA, Tallin, Estonia, 9IAEA, Santiago de Chile, Chile, 10IAEA, Pakistan, Pakistan, 11IAEA, Peking, China, 12IAEA, Vienna, Austria. Available software to process renographies present great differences between hardware companies both in the image display and in the parameter quantification. Independent software is not easily available. A new PC-compatible programme (interfile and dicom compatible) has been built for standization of the renographies and to allow all the Nuclear Medicine Departments to use clinicaly useful parameters as outflow efficiency or postmicturition retention.Methods: In order to validate the programme, 63 patients with unilateral hydronephrosis have been submitted to a MAG3 diuretic renogram, were analysed by two experienced observers . Before the software evaluation, the 2 observers arrived to a consensed procedure of how to process the renogram (extension of the kidney ROI, background area). All the studies of 63 patients were analysed two time. This software allows the user to define semiautomaticaly the usual areas (heart, both kidneys, background), as well as display optimized cortical image, sequential pre and postmicturition images, renographic and deconvolution curves, Patlak-Rutland plot and quantitative parameters (renal differential function by integral method and by deconvolution, ROE, NORA20, post-micturition retention, parenchymal transit time). Statistical analysis compared the intra and interobserver reproducibility of the 9 quantitative parameters of each kidney.Results: Distribution differences between two observers were under 5 % for all the parameters. Two-sample T test do not detect signifficant sifferences between variances of all the values both for the interobserver comparison as well as for the intraobserver analysis. Mean values of different quantitative parameters obtained by two obervers (2 time).

Function

Transit Time

PM/2 ROE (0+20) (%)

Observer

(%)

(min )

(%)

RK

LK

RK

LK

RK

LK

RK

LK

i

54

46

7

6.9

78

80

46

61

ii

54

46

6.8

7

77

80

48

61

1

i

52

48

7

6.8

75

78

57

66

ii

53

47

6.1

6.1

76

79

66

78

2

RK- Right Kidney, LK- Left kidneyConclusions: This PC based software seems to be a strong tool to process the diuretic renography. The comprehensive presentation include the major aspects to be analyzed in a renography (optimized cortical image, sequential images,

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postmicturition image, quantitative parameters as renographic and deconvolution curves, differential function, ROE, NORA, parenchymal transit time and post micturation retention index). Both the intra and the interobserver differences seem to be minimal.

P616

The interobserver variability in the measurement of partial function using renal scintigraphy with 99m Tc-MAG3 K. F. Wurm1, U. Wacker1, B. Clewing1, G. Becker2, F. Dammann1; 1 Department of Radiology and Nuclear Medicine, Göppingen, Germany, 2 Department of Radiotherapy and Radiooncology, Göppingen, Germany. Aim: Dynamic renal scintigraphy with 99mTc-MAG3 is a sensitive method for the evaluation of renal clearance. Furthermore information is the measurement of partial function for differentiation of the capacity of single kidney. Before surgical intervention or an external radiation it is necessary to know the exact value of the single kidney. The aim of our study was to evaluate the result of various analyses by different physicians ( interobserver variability )Materials and Methods: In a period of 3 months we investigated 20 patients ( 11 women, 9 men, mean age 52 years ) with different solid tumours. All patients obtained renal scintigraphy with 99mTc-MAG3. After measurement of the renal clearance five different physicians calculated the partial function of every kidney. The results get by the physicians were documented and compared.Results: The interobserver variability ranged from 1 % to 7 % in all cases. The systematic error as calculated from the total mean of all physicians is 3,62 % for the interobserver variability.Conclusions: Dynamic renal scintigraphy is an established method for the evaluation of renal clearance. The exact partial function is necessary before surgery or external radiation. We found a interobserver variability of 3,62 % in different physicians. Using a single calculation the exact value of the single kidney is not unfailingly. Before surgery or external radiation a second measurement of partial function with static 99mTc-DMSA scintigraphy presents a furthermore correlating value.

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E. Moralidis, G. Arsos, N. Karavida, N. Boussios, C. Sideris, K. Karakatsanis; Hippokration Hospital, Thessaloniki, Greece. Aim: It is accepted that under steady-state conditions there is a glomerulo-tubular balance. Tc99m-MAG3, a radiopharmaceutical with predominantly tubular handling, is characterized by higher extraction from the kidneys compared to Tc-99m-DTPA, thus justifying its preferential use. This study investigates the association between Tc-99m-MAG3 renography variables and glomerular filtration rate (GFR) values in kidney donor candidates.Methods: Twenty-six clinically healthy individuals, aged 52±12 yrs (range 32-80), candidates of renal transplant donation, referred for both GFR measurement and renography were enrolled. Individuals were submitted to two-sample, slope-intercept method, Cr-51-EDTA GFR measurement and to Tc99m-MAG3 renography. Split renal function, as proportion of the entire, was estimated from renography and subsequently the individual GFR value of each one of the 52 renal units was calculated. The following Tc-99m-MAG3 renography variables were assessed for each individual renal unit: time to maximal activity in kidneys (Tmax, in min), time to half the maximal kidney activity (T1/2, in min), time to 2/3 the maximal kidney activity (T2/3), and the normalized residual activity in kidneys at 20 min (NORA20). Spearman’s correlation coefficient and Fisher’s exact test were used in comparisons.Results: GFR values of the individual renal units, expressed in ml/min/1.73m2, ranged from 26 to 76, with a mean value of 48±14. No statistically significant correlation was found between GFR and Tmax, T1/2, T2/3, NORA20, or between GFR and the ratios of Tmax to T1/2, Tmax to T2/3 and T1/2 to T2/3. Considering as renographic criteria of normality Tmax”4min and T1/2”10min, 17 of the 26 renal units (65%) with a GFR•45 had a normal Tc-99m-MAG3 renogram, whereas 22 of the 26 renal units (85%) with a GFR<45 had a normal renogram (p=0.20).Conclusions: In kidney donor candidates, namely individuals without clinical evidence of significant renal damage, Tc-99m-MAG3 renography is not predictive of glomerular function. In this setting, GFR measurements by Cr-51EDTA (or Tc-99m-DTPA) appear appropriate.

P615 Unexpected presentations of urine leak in the transplant renogram: technical case reports F. Dede, B. Calsikan, T. Eerdil, H. Civen, T. Ones, S. Inanir, S. Tuglular, C. Yegen, E. Akoglu, T. Turoglu; Marmara University Hospital, Istanbul, Turkey. Aim: Transplant renogram (TR) is a noninvasive method to evaluate transplant and its complications including urine leak (UL). Findings of two cases in which the standard TR failed to demonstrate UL were presented. A 42 y.o. man (Case1) was referred for TR following a cadaveric renal transplant to show the cause of the right flank pain & decreased urine output. Another 36 y.o. asymptomatic male (Case2) was also referred for renogram following a living donor renal transplant to elucidate the reason of posttransplant creatinine elevation.Materials and Methods:For both pts, TR was performed for 60 mins after an i.v. injection of 99mTc-DTPA. Additional planar images were also obtained after interventions if necessary.Results:For Case1, the TR showed good perfusion and extraction function of the transplanted kidney with prolonged excretion. It also showed activity accumulation in catheterised bladder. After the irrigation of catheter by clinician to check for obstruction, right flank pain was increased and the planar image showed intense urine accumulation corresponding to painful swelling in the right flank consistent with UL. The TR of the second case revealed normal perfusion and functions in the renal transplant associated with DTPA accumulation in the uretero-vesical region. To exclude possible obstruction, diuretic renogram was performed. Post-diuretic images showed extravasation of activity into the abdominal cavity infront of the bladder suggestive of UL. During diuretic administration, suprapubic pain was occured beside anteriovesical urine accumulation on scan. For both cases surgical exploration or clinical followup were performed and UL secondary to necrosis of tip of the ureter were confirmed.Conclusions: Because UL needs urgent treatment, imaging of this complication is vital. Without maneuvers increasing mechanic pressure, the

Comparative evaluation of Cockcroft-Gault and Abbreviated MDRD Study Equations on a mixed cohort of patients referred for Glomerular Filtration rate (GFR) measurement by 51Cr-EDTA G. Arsos1, E. Moralidis1, N. Karavida1, N. Boussios1, P. Giamalis2, D. 1 Dept of Nuclear Ekonomidou2, G. Efstratiadis2, C. Karakatsanis1; Medicine, Aristotle University Medical School, Hippokration Hospital, 2 Thessaloniki, Greece, Dept of Nephrology, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece. Aim : GFR is the best estimator of kidney function both in health and disease and its measurement by 51Cr-EDTA (GFRm) remains the gold standard for clinical application. Alternatively, due to the limited access to the radionuclide technique, the use of GFR estimates (GFRes) derived by various equations based on serum creatinine (SCr) level and somatometric and demographic data has been suggested. The aim of the present study was to compare Cockcroft-Gault, (CG) equation with the newer (2000), “four variable”, abbreviated form of MDRD Study (aMDRD) equation, in GFR prediction, in a mixed non-pediatric population referred for radionuclide GFR measurement. Patients and methods : One hundred fifty two individuals (84 women), aged 48.7±16.4 yrs enrolled in the study (59 with chronic kidney disease [CKD], 42 candidate kidney donors, 37 renal transplant recipients, 10 renal transplant donors, and 4 with surgically corrected congenital hydronephrosis). All patients were submitted to slope-intercept, two-sample 51Cr-EDTA GFR measurement as well as to full biochemical evaluation including SCr measurement. GFRes were obtained using both CG and aMDRD equations. GFRes-GFRm association for both equations and between-GFRes association were assessed by linear regression. The GFR limits proposed by K/DOQI 2002 guidelines (•90, 60-89, 30-59, 15-29 and <15 ml/min/1.73 m2) were applied for CKD staging. Kappa statistics was used to evaluate the agreement between GFRes and GFRm in CDK staging. Results : The betweenGFRes correlation was excellent (r=0.94, p<0.0001). Both GFRes showed a good correlation to GFRm, with aMDRD correlating better than CG (r2 = 0.75 vs 0.68 respectively, p<0.05). Moreover the agreement between each GFRes and the GFRm in the staging of CKD was better for aMDRD compared to CG (ț = 0.404 vs 0.257 respectively, p<0.05). Conclusion : GFR estimates obtained by the application of CG and aMDRD equations are very well correlated to each other. However, GFR estimates by aMDRD equation correlates better with 51Cr-EDTA GFR measurements. Moreover, aMDRD, has a closer agreement to 51Cr-EDTA measurements in staging of CKD. Thus, the aMDRD equation should be preferred over CG equation for GFR estimation.

P49 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Endocrinology 1 P617 Administration of recombinant human TSH is effective in long-term monitoring and essential for maintenance of the well-being of thyroid cancer patients B. M. Grab-Duntas1, E. Mantzou2, L. H. Duntas2; 1Dept. Nuclear Medicine, Athens Medical Center, Athens, Greece, 2Endocrine Unit, Evgenidion Hospital, University of Athens Medical School, Greece. Periodic follow-up is imperative in patients with differentiated thyroid cancer (DTC) in order to assure long-term survival. Serum thyroglobulin (Tg) measurement and radioiodine whole-body scan (R-WBS) combined with neck ultrasound (US) are the chief modalities in this monitoring. Over the last few years recombinant human TSH (rhTSH, Thyrogen®, Genzyme) has been available for TSH stimulation as an alternative to LT4 withdrawal since it avoids often poorly tolerated hypothyroidism, serious impairment of the patient’s quality of life, reduced productivity and missed worktime. Aim: This study was designed to evaluate the safety and efficacy of rhTSH in a group of “low risk” patients.Materials and Methods: We investigated 42 consecutive “low-risk” (pT1N0M0). patients (33 females, 9 males, median age 52yr, range 26-72yrs) with histologically confirmed DTC. The patients had been undergone total thyreoidectomy and remnant ablation with 3.7 GBq 131I on average six months previously. The complete diagnostic follow-up was conducted in conjunction with administration of rhTSH after a standard protocol with two i.m. injections of 0.9 mg on two consecutive days. Tg and TSH were determined according to the protocol on days 3 and 5. Clinical examination and neck US were conducted in all the patients while R-WBS was performed only in the first 13 patients two days after 185 MBq 131 I in conformity with standard technique. All the other patients were followed up according to the consensus report as applies to low-risk patients (Schlumberger M et al., Eur J Endocrinol, 2004).Results: All patients (100%) attained sufficient TSH stimulation > 60 mU/L, achieving a maximum at day 3 and still slightly elevated levels at day 5. Basal Tg was undetectable (< 1 ng/mL) and rhTSH stimulated Tg concentrations were less than 3 ng/mL in all patients, and rhTSH stimulated R-WBS was negative. Compliance with this monitoring procedure was excellent and well-being maintained. The working patients missed only a few hours for the rhTSH-aided procedures. In a follow-up period of up to 5 years no patient has presented recurrence of the disease.Conclusions: We confirm the safety and efficacy of rhTSH in monitoring DTC patients. Our preference for this efficacious approach results from the excellent compliance and cost-effectiveness registered, achieved through preservation of the well-being and productivity of the patients. Moreover, our results fully corroborate the proposal of the consensus report since, in a 5-year observation time period, no patient treated as outlined above, has shown any sign of relapse.

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Poster Presentation

P613

Are Tc-99m-MAG3 renography variables predictors glomerular filtration rate in kidney donor candidates?

standard TR may failed to demonstrate the UL despite the positive clinical and laboratory findings.

P618 Assessment of ectopic thyroid gland in children with congenital hypothyroidism by color doppler ultrasonography and radionuclide imaging M. Tamam1, B. Bakır2, I. Adalet1, F. Darendeliler3, F. Bas3, Y. Sanli1, S. Cantez1; 1Istanbul University, Istanbul Medical Faculty Department of Nuclear Medicine, istanbul, Turkey, 2Istanbul University, Istanbul Medical Faculty Department of Radiodiagnostic, istanbul, Turkey, 3Istanbul University, Istanbul Medical Faculty Department of Pediatric Endocrinology, istanbul, Turkey. AIM: Thyroid disgenesis (aplasia, hypoplasia or ectopia) is among the most frequent cause of congenital hypothyroidism(CH). The widely and effectively used imaging techniques in diagnosing CH are radionuclide imaging (RI) and thyroid gray-scale ultrasonography (GSU). Compared to RI, the efficiency and reliability of GSU in localizing ectopic thyroid gland (ETG) were not as satisfactory. In recent years, Color Doppler Ultrasonography (CDU) was found effective in detecting ETG. With this study we aim to compare the sensitivity of RI, GSU and CDU in identify the localization of ETG. METHOD: 182 patients who were found to have elevated TSH levels or who were treated because of CH in pediatric endocrinology department,were enrolled in this study in order to establish the etiology of CH. All the patients underwent GSU and RI investigations. CDU were applied to 112 patients. For RI, 100.000-count images were acquired after administration of 1-2 mCi Tc99m-pertechnetate intravenously. Images were obtained in the anterior and lateral views using a gamma camera equipped with a pin-hole collimator. CDU were used to assess the vascularity of ETG, as well as its size, localization, echogenicity, and echotexture. RESULTS: RI detected ectopic localization in lingual region in 32 cases (25F, 7M); in which GSU interpreted 26 cases as agenesis and 4 as hypoplasia. In contrary, CDU detected ETG in 21 patients (70%) and agenesis in 9 (30%). CDU, detection sensitivity, specificity, positive and negative predictive values for ectopia were 80%, 98.8 %, 95.3 %, and 94.4 %, respectively. Among 21 cases of ETG, 17 were located at the infrahyoid level and 4 were at the suprahyoid level. 17 patients had hypovascular ectopia, where as 4 cases were hypervascular. The assessment of echogenicity in ETG cases revealed 7 cases as izoechoic, 13 cases as izo-hypoechoic, 1 case as hyperechoic. CONCLUSION:CDU is a noninvasive imaging tecnique that can be used as a first line image examination for evaluating CH. However, highly radiologist- and equipment-dependent interpretation of CDU and difficulty in applying to neonates lowers the sensitivity in identifying ETG, compared to RI. For this reason in cases of tiroid agenesis detected by CDU or GSU, RI techniques should be applied in order to confirm the diagnosis.

P619 Determination of thyroglobulin cut-off value as an indicator for progressive disease, correlations between gender, histopathologic type, extracapsular invasion and progressive disease in patients group of same ages with differentiated thyroid cancer G. Aras, S. S. Gultekin, N. O. Kucuk; Ankara University Medical Faculty, Department of Nuclear Medicine, Ankara, Turkey. Aim: Aim of this study was to ascertain thyroglobulin (Tg) cut-off value and to research a correlation between gender, histopathologic type, extracapsular invasion and progressive disease. Method: 324 patients were included in our study. 158 patients were treated with 200-1550 mCi radioiodine therapy after radioiodine ablation (RA) to progressive disease (group 1:104-F,54M;age and mean;12-79, 45,3+16 years, follow-up period;24-85 months, histopathology;127papillary, 31-follicular). 166 patients were treated with 75-125 mCi to RA and they had no progression on the follow-up period (group 2:122-F, 44-M; age and mean;24-86, 47+12 years, follow-up period;21-72 months, histopathology;145-papillary, 21-follicular). We obtained Tg values in the 6-12 months period after RA (L-thyroxin off for 4-weeks). All of the patients were recorded according to gender, age, histopathologic type and extracapsular invasion at the time of diagnosis. Data were analyzed by statistical methods. Results: Firstly, distribution of ages was examined by statistical analyses for two groups. Homogeneously distribution was found (student’s t test, p > 0,05). Tg median values for two groups (group-1;76,4, group-2:1,62) were compared by Mann Whitney test. The statistical difference was observed between groups (p<0,001). Sensitivity 79%, specificity 97% and cut-off Tg value 9,25 ng/ml were detected using ROC curve analyses (UAC=0,886, p<0,001) and Youden’s index. For different Tg cut-off values were also evaluated. So, we obtained sensitivity 80%, specificity 92% while Tg level was 5 ng/ml. However, sensitivity and specificity were equal (82%) for 2 ng/ml Tg level. Risk of progression was evaluated via Odds Ratio (OR). Tg cut-off level > 9,25 was one hundred twenty one times higher risk than Tg cut-off level < 9,25 ng/ml (OR:120,994, confidence interval (CI): 45,899-318,951). The two groups were analyzed by Chi-Square test. Significant difference was not observed according to the gender between two groups (x2=2,26, p=0,133, p>0,05). There were significant statistically differences for histopathologic type and especially extracapsular invasion (respectively, x2=5,73, p=0,017, p<0,05 ve x2=71,30, p<0,001) between group 1 and 2. Risk of progressive disease was higher two times for follicular type (OR:2,037, CI:1,130-3,674) and eight times for extracapsular invasion (OR:7,756, CI:4,717-12,752). Conclusion: Tg cut-off value for progressive disease was determined 9,25 ng/ml with Youden’s index. When Tg cut-off level was accepted 2 ng/ml, sensitivity and specificity found equally (82%) while age effect was similar for groups, gender had not any effect to progressive disease. On the other hand, an important relationship was ascertained between progressive disease and follicular type, especially if there was an extracapsular invasion.

P620 Thyroid “stunning” after whole body scintigraphy with 131 14,8MBq (400 µCi) of I J. M. A. Neto; Portuguese Cancer Institute of Coimbra - Francisco Gentil. IPOC-FG, EPE, Coimbra, Portugal.

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Aim: Thyroid “stunning” is frequently described as a phenomenon that occurs when a administration of diagnostic activity of 131I is followed by a decrease in the uptake by normal thyroid tissue or differentiated thyroid cancer of a subsquent radioiodine activity. To reduce the probability of thyroid “stunning” we usually use in our Institution, for the first whole body scan after thyroid carcinoma surgery, an activity of 14,8 MBq of 131I. The aim of this study was to evaluate thyroid “stunning” with this protocol.Materials and Methods: We prospectively studied, between August 2004 and July 2005, 24 patients who had undergone total thyroidectomy for differentiated thyroid cancer: 21 female, 3 male, average age 44,8 ± 15 years. We measured uptake in the thyroid bed 24 hours after oral administration of 14,8 MBq of 131I for diagnostic scan and 24 hours after ablation therapy with radioiodine. We used a Siemens E.Cam DCR dualhead gamma camera equipped with high-energy parallel-hole collimators for imaging an aliquot of the administered activity, a capsule of iodine 131 placed in a neck phantom, 30 cm away from the collimator, and patients under exactly the same conditions. We included patients with cervical uptake in whole body scan 1% or higher.Results: The range and median values for uptake of radionuclide in the thyroid remnant for the diagnostic scan were 1,02%, 18,05% and 5,03% and for therapy were 0,34%, 11,84% and 3,47% respectively. The therapy uptake was significantly lower (P<0.001) than the diagnostic uptake. We observed reduced uptake of the therapeutic radioiodine in 22 patients (91,7%) with a median value of -39,64% of the diagnostic uptake.Conclusions: We observed “stunning” in thyroid remnant in 22 (91,7%) of patients after whole body scan with 14,8 MBq of radioiodine. The possibility of “auto-stunning” must be considere and ruled out by the use of 123I in diagnostic scintigraphy.

P621 Need for screening for Hashimoto`s thyroiditis in high-risk patients K. Zaplatnikov1, W. Wiedemann2, M. Plotkin3, F. Grünwald4; 1Nuclear Medicine Clinic Nürnberg, Department of Nuclear Medicine, University Clinic, Frankfurt/M, Germany, 2Nuclear Medicine Clinic, Nürnberg, Germany, 3Department of Radiology, Nuclear Medicine and Radiooncology, Campus Virchow-Klinikum, University Clinic Charité, Berlin, Germany, 4 Department of Nuclear Medicine, University Clinic, Frankfurt/M, Germany. Aim Both the familial predisposition and environment are known to play a role in the pathophysiology of the Hashimoto-thyroiditis (HT). In the presented retrospective study, we studied relatives of patients with HT among the population of ethnic Germans from Kasachstan. The aim of the investigation was to assess the risk for HT in this patient group. Methods We prospectively 59 first-grade relatives (f47; m12; median age, 32 +/-14 yrs) of pat., suffering on HT. 35/59 studied pat. (60%) were residents of North-eastern regions of Kazakhstan, prior to their relocation to Germany. Initially, a clinical investigation and a thyroid sonography were performed; and thyroid hormone levels (fT4, fT3, TSH) as well as anti-TPO and anti-Tg antibodies titres were measured. The measurements of the antibodies titres were repeated 6, 12, 18 and 24 months later. The exclusion criteria were a history of thyroid surgery, radioiodine therapy or thyroid hormone medication. No subjects had a iodine exposure in the last 6 months prior to the first investigation. Results Titres of anti-TPO antibodies were elevated in 40/59 pat. In 23 of them, high titres of anti-Tg antibodies were found. 4 further pat. had an isolated elevation of anti-Tg antibodies. In 26/59 pat., a diffuse hypoechogeniety of thyroid was detected by sonography. To the time point of the first investigation, a hypothyroidism was depicted in 8 pat. During the observation time of 12 mo, 29 pat. developed a latent hypothyreoidism (isolated TSH elevation) and 3 pat. have fT4 depression; 24 mo later further 4 pat. developed a latent hypothyreoidism. Conclusions A high prevalence (75%) of HT in first-grade relatives of patients suffering on HT in our study might be related to the two factors: the well known genetic predisposition to the HT (2) and the fact, that a majority of them were previously residents of North-eastern regions of Kazakhstan. Indeed, a high incidence of HT in the regions, adjacent to the Semipalatinsk nuclear test site was reported in the literature (1). Our results justify a screening for HT in this population group. Literature: 1. Zhumadilov Z et al. Thyroid abnormality trend over time in northeastern regions of Kazakstan, adjacent to the Semipalatinsk nuclear test site. J Radiat Res 2000; 41: 35-44. 2. Barbesino G, Chiovato L. The genetics of Hashimoto's disease. Endocrinol Metab Clin North Am. 2000;29: 357-374.

P622 Thyroid Pin-Hole spect ,clinical interset of a new acquisition and program reconstruction G. Beersaerts, S. Nerinckx; Clinique Sainte-Anne-Saint-Remi, Bruxelles, Belgium. Aim of the study evaluation of PHS(Pin-Hole Spect) as a new method of acquisition and reconstruction of Pinhole Spect Thyroid image.A comparison with an other method of reconstruction (P-spect) was performed. Matherial and methods Camera: Millenium VG Injection :120 Mbq tc 99m A static image is acquired 20 min. after injection with a Pinhole collimator ( insert 5 mm) A pinhole tomography is realised (starting angle 270°, ending angle 90°) Acquisition time 32 sec./ step Acquisition matrix 128*128 Acquisition angle 3° by step The data are reconstructed on a Xeleris computer using a dedicated iterative reconstruction software PHS . About 30 patients were scanned and the results were compared to the echography. A complementary study was started to improved the image quality and the detection of nodules by modifying the smoothing, the number of iterations, and the number of pixels . Results The tomographic method allowed the detection of nodules smaller than 6 mm diameter. A comparison between PHS and an other method (P-spect) shows a much better image and discrimination of nodules . We can also said that there is less distortion of the image . Conclusions After our first results , the image quality and the detection limit of small thyroid nodules was already pretty good. The PHS methods seems to be better than the P-spect processing.

The effects of antithyroid therapy for the cardiac functions in subclinical and overt hyperthyroidism A. Sukan, A. Tekin, O. Tekin, O. S. Bakiner, M. Aydin, M. Reyhan, A. F. Yapar; Baskent University, Adana, Turkey. Aim: The aim of this study is to evaluate the effects of the antithyroid therapy in subclinical and clinical overt hyperthyroidism for the cardiac parameters and to compare radionuclide methods with echocardiography (ECHO).Methods: The preliminary results of this prospective study consisted of 7 patients (median age 35 ± 10 yr; range 23-60) recently diagnosed, one patient as subclinical and the remaining 6 as overt hyperthyroidism. The patients were submitted to clinical, laboratory and cardiac evaluation comprising radionuclide ventriculography (RNV), multigated acquisition (MUGA), gated blood pool SPECT and echocardiography (ECHO).before and after reaching euthyroid state.Left ventricular systolic and diastolic functions were measured by each technique. The following indices were determined with ECHO: peak E (E), peak A (A), mitral E deceleration time, mitral A deceleration time, isovolumetric relaxation time(IVRT), isovolumetric contraction time (IVCT), E acceleration time. The early parameters determined by MUGA were: ejection fraction (EF), heart rate (HR), peak ejection rate (PER), time to peak filling (TPF), peak filling rate (PFR).Results: After reaching euthyroidism, we found a significant increase in TPF and PFR (p= 0.02, 0.01, respectively). HR, EF, and PER indices showed a decrease, although not statistically significant, within the normal ranges (p=0.07, 0.8, 0.07, respectively). ECHO data revealed an increase in E deceleration time, IVCT, IVRT in the euthyroid state which were not statistically significant (p=0.2, 0.4, 0.07, respectively). The E/A ratio showed a slight decrease which was also not significant (p=0.1).Conclusions: The early results of the study suggest that hyperthyroidism is associated with enhanced diastolic function at which antithyroid drugs has a significant influence on the cardiac diastolic parameters.

P624 Minimally invasive gamma probe parathyroid surgery - initial report.

guided

reoperative

A. Hubalewska-Dydejczyk1, M. Barczynski2, A. Konturek2, S. Cichon2, A. 1 Sowa-Staszczak1, B. Huszno1; Nuclear Medicine Unit, Chair and Department of Endocrinology Medical College, Jagiellonian University, 2 Krakow, Poland, Department of Endocrine Surgery, 3rd Chair of General Surgery, Medical College, Jagiellonian University, Krakow, Poland. Background and aims: Reoperations for recurrent or persistent hyperparathyroidism (HPT) remains difficult even in the most experienced hands. In repeat operations, the success rate is 1015% lower than the primary procedure, with increased perioperative complications including recurrent laryngeal nerve damage and hypoparathyroidism. Parathyroid gland’s color and shape so crucial for macroscopic identification are usually obscured by fibrosis within the scar tissue. Tenuous blood supply to remaining parathyroids may also exist after primary exploration, so minimizing dissection in these patients is critical. The aim of this study was to evaluate the usefulness of the method of minimally invasive gamma probe guided reoperative parathyroid surgery.Materials and Methods: The study included 8 patients undergoing surgery between 06/2005 and 03/2006 (mean age 51.3±6.7 years; F:M ratio 7:1), with biochemically confirmed persistent HPT in one case, recurrent primary HPT in 3 cases and recurrent secondary renal HPT in four cases. Preoperative localization procedures included high-resolution ultrasound (US) of the neck and subtraction parathyroid (SS) scintigraphy (99mPertechnectate and 99mTc-MIBI) of the neck and mediastinum. Patients were administered 5mCi of 99mTc-MIBI i.v. 30 minutes prior to surgery. Gamma Finder II handheld wireless gamma probe was used (World of Medicine, Orlando, USA). The site of the neck with radioactivity at least 20% higher than background was considered to harbor the hyperactive parathyroid gland and directed the initial skin incision (3cm in length). Surgery was terminated after successful removing of hyperactive parathyroid gland (tissue to background ratio higher than 20%) and obtaining remarkable decrease of serum iPTH level (Future-Diagnostics, Wijchen, The Netherlands).Results: Preoperative localization with US and SS was concordant in 4 cases only. The gamma probe successfully identified the site of the neck harboring a solitary hyperactive parathyroid tissue in 7 patients in which focused parathyroidectomy was performed. In one patient the gamma probe scanning of the neck was negative. That patient underwent bilateral neck exploration with final transcervical dissection of left thymus harboring an ectopic hyperactive parathyroid gland. There was no postoperative morbidity.Conclusions: We do find that radioguidance is a valuable adjunct to reoperative parathyroid surgery. It allowed for focused skin incision and focused neck exploration instead of conventional bilateral neck exploration usually undertaken in cases of reoperative parathyroid surgery. Radioguidance was also helpful in identification of the ectopic hyperfunctioning parathyroid tissue localized in ectopic site (upper mediastinum).

P625 Bone turnover and bone mineral density in premenopausal women with Graves' disease K. Zaletel, T. Kocjan, S. Gaberscek, E. Pirnat, J. Prezelj, S. Hojker; University Medical Centre, Ljubljana, Slovenia. Aim. Hyperthyroidism is associated with accelerated bone remodeling and reduced bone mineral density (BMD). Graves’ disease (GD) is the most prevalent cause of hyperthyroidism in premenopausal women; however, there is less data on BMD and bone turnover in this group of patients before initiation of treatment. Patients and methods. We included 84 newly diagnosed premenopausal females with GD before initiation of treatment, aged between 20 and 56 yrs (mean, 36.6 yrs). The duration of symptoms characteristic for hyperthyroidism was 0.5 - 12 months (mean, 2.8 months). The fT4 median value before starting treatment was 62.7 pmol/L (min, 24.9 and max, 154.8 pmol/L), the fT3 median value was 24.8 pmol/l (min, 8.4 and max, 30.8 pmol/L) and the median value of thyroid stimulating autoantibodies (TSAb) was 14 IU/l (min, 2 and max, 41 IU/L). At the time of diagnosis BMD of the lumbar spine and the hip were assessed with dual X-ray absorptiometry (DXA). Concomitantly, bone turnover markers bone alkaline phosphatase (BALP) and serum crosslaps (CTX) were measured. Results. Only 44 patients (52.4%) presented with normal BMD, while in 35 patients (41.7%) we diagnosed

osteopenia and in 5 patients (5.9%) even osteoporosis. Both fT4 and fT3 showed significant correlation with BMD at the total hip (p<0.05), while no correlation with BMD at the lumbar spine was found. The significant correlation of CTX level with both thyroid hormones and TSAb was established (p<0.00002 and p<0.02, respectively). On the other hand, we found no correlation of BALP level with the level of thyroid hormones or TSAb. Body weight significantly correlated with BMD at either site (p<0.0002). There was no association of BMD or bone turnover markers with the duration of symptoms. Conclusion. Our results indicate that low BMD is a common problem even in premenopausal women with GD. The degree of BMD loss and bone resorption seems to be dependent on severity of hyperthyroidism and autoimmune process, while duration of disease is probably less important.

P626 OnT4-thyroglubulin assay predicts prognosis in low-risk differentiated thyroid carcinoma as well as TSH-stimulated assay. L. Giovanella1, L. Ceriani1, F. Keller2, A. Ghelfo3; 1Oncology Institute of Southern Switzerland, Bellinzona, Switzerland, 2EOLAB Clinical Chemistry and Laboratory Medicine, Bellinzona, Switzerland, 3University Hospital, Varese, Italy. Background The TSH-stimulated TG assay was proposed as pivotal test to evaluate patients with low-risk DTC, However, TG assay under thyroxine treatment showed very high accuracy in these patients, particularly due to high negative predictive value. Aim To evaluate the predictive role of onT4-TG assay performed after thyroidectomy and radioiodine ablation on overall survival and disease-free survival of low-risk DTC patients. Patients and Methods We enrolled 312 patients with DTC and treated by total thyroidectomy plus 3700 MBq 131J administration. Admission criteria were: 1. complete tumour surgical excision, 2. non extra-thyroid area radioiodine uptake at post-treatment scan and 3. undetectable TG 3 months post-radioiodine treatment. One year after primary treatment all patients underwent onT4-TG assay as well as offT4 or rhTSH-stimulated TG assay. Other procedures as neck ultrasound, radioiodine WBS, PET, CT or RM were performed if needed. Relationship between onT4-TG and other variables and OS/DFS was evaluated by both univariate (ANOVA) and multivariate (Logistic Regression) analysis. Results Negative onT4-TG assay is strongly related with OS and DFS of patients with low-risk DTC reaching a negative predictive value of 98.0% for OS and 97.8% for DFS. Spearmann rank analysis showed no significant difference between onT4 and TSH-stimulated Tg assay. Conclusions Due to high NPV of onT4-TG assay, the additional role of TSH-stimulated TG Assay is very limited in this homogeneously defined low-risk patients group, representing a large part of patients affected by DTC.

P627 Iodide organification disorder in autonomous thyroid nodule B. Tang1, B. Corvilain1, A. Seret2, C. Daumerie3, R. Moreno-Reyes4; 1 Université Libre de Bruxelles, Brussels, Belgium, 2Université de Liège, Liège, Belgium, 3Université Catholique de Louvain, Brussels, Belgium, 4 Université Libre de Bruxelles, brussels, Belgium. Introduction: Somatic mutations of the thyrotropin receptor (TSHr) gene and the G-protein Gs are considered to be the more frequent cause of autonomous thyroid nodule (ATN). These mutations cause the uncontrolled activation of the cAMP cascade. TSHr mutations rarely also stimulate the Ca++-IP3 cascade. In human, in vitro data show that cAMP cascade down-regulates iodide organification. Therefore it was hypothesized that some level of organification defect may exist in the majority of ATN. Aim: The aim of this work was to study iodide organification in ATN and its possible relationship with thyroid function. Methods: 43 patients, 12 males and 31 females with a single ATN were included. For each patient we obtained FT3, FT4, TSH serum measurement. The test was considered positive (P+) when the discharge of 123I from the ATN was greater than 15% one hour after the administration of perchlorate. A negative test was identified as P-. Additionally, the uptake of 123I in the ATN was calculated before and after perchlorate administration. Results: 13 (30%) of patients had a TSH level < 0.04 µU/ml and 30 (70%) between 0.04 and 0.4 µU/ml. 27 (63%) of ATN were P+. Perchlorate discharge in P+ was -42.29 ± 13.13% and in P- -3.23 ± 8.44 (p<0.0001). The 123I uptake in P- after perchlorate administration was higher than that in P+ (p=0.03). When comparing 123I uptake and hormone level, we found that FT3 was significantly correlated (r=0.74) with the 123I uptake after the perchlorate administration in the P- group. Such correlation was not found in the P+ group. Conclusions: The perchlorate discharge test showed iodide organification impairment in most ATN. In addition, only in ATN with normal iodide organification serum FT3 concentrations were correlated with 123I uptake. Differences in organification defect may partially determine the occurrence of hyperthyroidism in subjects with ATN. The possible relationship between the level of organification defect and the mutation causing ATN has still to be studied.

P628 Is neopterine a good biomarker for thyroid diseases? C. Koerber, N. Körber-Hafner; Nuklearmedizinische Praxis, Fulda, Germany. AIM: Neopterine is considered to be one of the markers of immunity system activity. An increased level of this pteridine derivate is determined in blood or urine in infections, transplant rejections, and in other conditions accompanied by changes in the immunity system. Our aim was to determine the potential for autoimmune thyreoid diseases.Methods: 680 patients with thyroid diseases were diagnosed and treated according to current guidelines. The blood parameters were investigated usind test kits (BRAHMS Diagnostika, Berlin, Germany). The statistical analysis was performed with a student´s t-test. The significance level used was <0,05.Results: 291 out of 680 patients were diagnosed with an autoimmune thyroid disease, 389 showed no signs of a thyroid impairment. The mean age of all patients was 49,4 ± 20,4 years. For the group of patients with a thyroiditis the following antibody results were determined: TPO 1420,3±1789,9, neopterine 17,5 ± 42,2, anti-Tg 158,8 ±136,6, TRAK 1,5 ± 0,9. For the patients

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Poster Presentation

P623

with an autoimmune thyroid disease: TPO 20,3 ± 12,2, neopterine 8,7 ± 3,2, anti-Tg 58,8 ± 109,5, TRAK 0,3 ± 0,2. Using the student´s t-test the following significance levels were found: TPO <0,002, neopterine <0,14, anti-Tg <0,92 and TRAK <0,17. CONCLION: Neopterine reached no significance level in the determination of an autoimmune thyroid disease.

pg/ml vs. 20 ± 8 pg/ml respectively) (P >0.05 for all).Conclusions: Disturbances in bone metabolism are present only in Graves’ disease & not in all cases of hyperthyroidism. Addition of Bone scan to diagnostic work up of Graves’ patients is a sensitive indictor for metabolic bone changes and could help in future management and follow up for this group of patients.

P629

P632

Factors that effect the success of radioactive iodine treatment in patients with hyperthyroidism

Comparison of T lymphocyte cytokine production pattern in patients with Hashimoto's thyroiditis and Graves’ disease

E. Özdemir, S. Türkölmez, R. Orak, D. Cayır, G. Koca, K. Demirel, M. Korkmaz; Ankara Training And Research Hospital, Ankara, Turkey.

H. Duan, S. Schwarzmair, M. Schuetz, S. Kontur, A. Antoni, K. Wahl, S. Kommata, K. Kletter, R. Dudczak, M. Willheim, G. Karanikas; Medical University of Vienna, Vienna, Austria.

The aim of this study was to evaluate the factors that effect the success rates of radioactive iodine (I131) treatment in patients with Graves Disease and toxic nodular goitre. Material- Method: Fortytwo patients (mean age=56.6±12.4, 37 women) with either Graves Disease (n=10) or toxic nodular goitre (n=32) and who received I131 treatment were studied. The pretreatment evaluation included thyroid function tests, antimycrosomal and antithyroglobulin antibodies, thyroid ultrasonography, throid scintigraphy and radioactive iodide uptake levels at 4 and 24 hours. The I131 treatment was deemed successful in case the 1-year fT3, fT4 and TSH levels were compatible with either hypo or euthyroid state, and unsuccessful otherwise. The effect of pretreatment fT3, fT4, TSH, anti M, anti T, RAIU4 and RAIU24 levels, thyroid volume, antithyroid medication use and the type of disease on the success of I131 treatment was evaluated.Results:The I131 treatment was successful in 32 (76.2%, responders) and unsuccessful in 10 (23.8%, nonresponders) patients at 1 year. The dose of I131 was similar in responders and nonresponders. The treatment was successful in 71% of patients with TNG and in 90% of Those with Graves disease (p:0.402). Although the responders had higher pretreatment fT3 and fT4 levels, the difference was not significant. Similarly, the responders had nonsignificantly lower pretreatment antiM and antiT levels. The baseline thyroid volume as assessed by thyroid US was greater in the responders. The pretreatment RAIU4 and RAIU24 levels were similar in the 2 groups. The I131 treatment was successful in 69.4% of patients with history of pretreatment antithyroid medication use as opposed to 82.4% of those without (p:0.203)Conclusions: The success rate of I131 treatment in patients with hyperthyroidism has been found to trend towards an increase with high pretreatment fT3, fT4 levels and large thyroid volumes and decrease with pretreatment antithyroid medication use.

P630 The Value of Ultrasonography in the Evaluation of the Thyroid Pyramidal Lobe D. Çayir, M. Ezer, S. Türkölmez, E. Özdemir, G. Koca, K. Demirel, M. Korkmaz; Ankara Training and Research Hospital, Ankara, Turkey. Aim: It is important to determine the presence of the pyramidal lobe in thyroid surgery. The pyramidal lobe is known to carry a high risk of thyroid disease recurrence. The pyramidal lobe can be visualized easily using scintigraphy. The aim of this study is to evaluate the value of ultrasonography in the detection of the pyramidal lobe.Materials and Methods: One-hundred twenty-five patients (105 female, 20 male; mean age: 42.86±14.50 y , range: 12-78 y) were included in this study. The technetium-99m pertechnetate (Tc-99m) thyroid scintigraphy was performed and the presence of pyramidal lobe and its site of origin were determined. Thyroid function status of the patients was also determined. Thyroid ultrasonography (US) was performed to all patients without knowledge of the scintigraphy results.Results: Pyramidal lobe was positive in 79 patients (63.2 %) on thyroid scintigraphy. Of the 79 pyramidal lobes identified, 43 % arose from the right, 49.4 % from the left and 7.6 % from the isthmus. Pyramidal lobe was detected by US in 60 of 125 patients (48 %). The sensitivity, specificity and accuracy for US were 63.3 %, 78.3 % and 68.8 %, respectively. There was no correlation between the thyroid function status and the positivity of pyramidal lobe on US. Conclusion: We found that US has limited role in the evaluation of the thyroid pyramidal lobe. The frequency of recurrent thyroid disease involving the pyramidal lobe after surgery highlights the importance of its detection using scintigraphy.

P631 Metabolic super scan in patients with hyperthyroidism: Does it have a clinical significance? M. H. Kotb1, T. A. F. El-Maghraby2, K. M. E. Khalaf allah1; 1National Cancer Institute, Cairo, Egypt, 2Cairo University, Cairo, Egypt, Saad Specialist Hospital, Al-Khobar, Saudi Arabia. Hyperthyroid patients complain of generalized bony aches frequently overlooked by more prominent symptoms from cardiovascular & nervous disturbances. Hyperthyroid patients are expected to have abnormal bone metabolism as part of the generalized hypermetabolic status. The aim is to verify the presence of metabolic bone super-scan in hyperthyroid patients. Secondly, to correlate presence of super-scan with various lab results.Materials and Methods: 45 patients with hyperthyroidism by clinical & lab results were enrolled. In all 99mTc thyroid scan & uptake & in a different day, 99mTc-MDP bone scans were acquired. Serum T4, TSH, Ca, ALP & PTH levels were monitored in all as markers of thyroid & bone metabolism. 10 control cases with no thyroid diseases were included. Patients with thyroiditis or on antithyroid drugs for > 1 year were excluded. 6 criteria were set for the diagnosis of metabolic super-scan (MSS) (prominent uptake in calvarium, Sternum, Bone/soft tissue, faint kidneys, prominent appendicular skeleton and beaded costal ends) & presence of > 3 was considered diagnostic.Results: According to hormonal & thyroid scans, patients were subdivided into Graves’ (n=30), Toxic Nodular Goiter (TNG) (n=10) and Autonomous toxic adenoma (AT) in 5 cases. TSH for the whole group was 0.005±0.003 IU which was significantly suppressed compared to controls 1.7± 0.5 IU. TSH values for Graves’ were 0.003±0.001IU, TNG 0.005 ±0.002 & 0.007 ± 0.002 IU for AT with no significant differences (P>0.05 for all). Uptake values for all were 18±8%, which were significantly higher than control 2.5 ±1% (P<0.01). Uptake for Graves’ 24 ±4% was significantly higher than TNG & AT (15 ± 5% & 10 ±2% respectively) (P< 0.05 for both). MSS was present in 90% (27/30) of Graves’ cases, while it was present in only 2 patients (20%) from the TNG and in none from AT group. None of controls showed features of MSS. There were no significant differences regarding Ca, ALP & PTH between Graves’ & nonGraves’ groups (8.7 ± 0.6 mg/dL vs. 8.4 ±0.4 mg/dL, 180 ±60 U/L vs. 170 ± 55 U/L and 22 ±10

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Aim: The aim of our study was a direct comparison between Graves`disease (GD) and Hashimoto`s thyroiditis (HT) with a systematic identification and correlation of cytokine production pattern.Materials and Methods: The study was performed by fifty-eight consecutive patients (aged 22-65). The patients were divided in two groups: Group I: Twenty-nine patients with HT and Group II: Twenty-nine patients with Graves’ disease. Twenty-nine healthy volunteers, free of thyroid disease (Group III) matched in sex and age consisted the control group. All patients had measurement of thyroid hormones (free thyroxine, free trijodthyronine), thyrotropin (TSH), autoantibodies (TgAb, TPOAb, TSH-RAb), and cytokine production pattern by flow cytometric intracellular cytokine detection in CD4+ and CD8+ T cells of peripheral blood mononuclear cells (PBMC).Results: We found a significant difference for the frequency of cells producing IFNȖ and TNFĮ within the CD4+ and CD8+ subsets, but no significant difference for IL4, IL5, IL6, IL10, IL13 and TNFȕ of HT patients in comparison to GD patients and to controls, respectively. The difference in cytokine production pattern was more pronounced in CD8+ cells than in CD4+ cells. Interestingly, we did not find any significant difference for Th2 cytokines between GD patients and HT patients and controls, respectively.Conclusions: Our data demonstrate that in HT patients only the Th1 cytokines are activated. On the other hand, surprisingly the peripheral CD4+ and CD8+ T lymphocytes from GD patients showed no significant differences to controls neither in their Th1 nor Th2 cytokine patterns.

P633 Determination of total iodine concentration in urine of patients candidates to radio 131-Iodine therapy by a colorimetric chronotitration detection. M. Asti1, G. De Pietri1, A. F. Sedda2, R. Sghedoni1, E. Grassi1, A. Filice1, A. Fraternali1, D. Salvo1; 1Santa Maria Nuova Hospital, Reggio Emilia, Italy, 2 TRIGA Reactor ENEA, Roma, Italy. Aim: Description and evaluation of a new method for the determination of iodine concentration in urine. A correlation between amount of iodine in urine and concentration of thyroid parameters in blood of patients candidates to 131-iodine therapy was attempted.Materials and Methods: The determination of the amount of iodine in blood is fundamental for patients affected by thyroid pathologies such as carcinomas and hyperthyroidisms before treatment with 131Iodine. As a matter of fact, non-radioactive iodine in blood competes with the absorption of the radioactive atoms in thyroid decreasing the effectiveness of the therapy. It is known that iodine amount in blood is related to iodine amount in urine so a simple method based on the SandellKolthoff reaction was developed and routinely used. The method utilizes the fact that iodide acts as a catalyzer in the reduction of ion Ce4+(yellow) to Ce3+(colorless) coupled to oxidation of ion As3+ to As5+, so reaction rate is proportional to the iodide amount in solution. The following steps were carried out: 1) removing interfering substances by oxidation with the addition of a 28% solution of chloric acid to the samples 2) heating the samples for about 120 minutes at 110°C with subsequent cooling 3) adding a solution of 10 mg/ml of As2O3 to create a reducing environment 4) adding a drop of ortho-ferro-phenanthroline to indicate the state of reaction and to determine the exact time of color change 5) adding a solution of 0.2 N cerium sulphate as oxidizing agent and beginning the time counting 6) monitoring the solution color change and at the appearance of the first visible pink-orange shade, stopping and recording the time 7) determining the iodine content in the solution by comparison with a calibration curve. Furthermore iodine concentration in urine was compared, before treatment, to HTG and TSH in patients affected by thyroid carcinoma (n = 92) and to TSH, FT3 and FT4 in patients affected by hyperthyroidism (n = 40).Results: For patients whose iodine concentration resulted greater than 50 µg/dl, radio 131-Iodine therapy was delayed until a new determination showed a normalization of the value. Iodine amount in urine doesn’t appear to be correlated with any other thyroid parameters (r < 0.3 in every case).Conclusions: This new method results reliable, accurate and sensitive and can be applied in every Nuclear Medicine Division without acquisition of complex and expensive analytical instruments.

P634 Recovery time from hyperthyroidism after individualized radioiodine treatment in patients affected by uni or multifocal autonomy M. Carletto, C. Canzi, V. Longari, M. Castellani, P. Gerundini; Fondazione IRCCS Ospedale Maggiore, Milano, Italy. Objectives: Aim of the study was to evaluate the recovery time from hyperthyroidism after individualized radioiodine therapy in pts with uni or multifocal autonomy. Methods: One hundred and eleven pts (age 66± 10,79F,32M) with uni (42%) or multifocal (58%) autonomy were treated over the last 5 yrs. A subclinical hyperthyroidism was found in 52% of pts with suppressed TSH (normal range: 0.26-4.2 mU/L) and normal serum values of FT3 and FT4 (range: 3.8-8.0 pmol/l and 9.0-20.0 pmol/l respectively). Clinical hyperthyroidism was observed in the remaining 48% with suppressed TSH and high FT3 and/or FT4 serum values. After a 123I dosimetric study based on thyroid uptake measurements at five time points, each patient received an individualized 131I therapeutic activity. All treatments were as outpatients. Patients were free from antithyroid drugs over 1 month before dosimetry and therapy. Patient clinical status was monitored by repeated TSH, FT3 and FT4 serum value assays 1,3,6,12 months after therapy and then once a year. Mean administered activity was 367± 130MBq [range 111-600] and mean

FOLLOW-UP AT 6, 12 AND 60 MONTHS Monitored pts / Treated pts

102/108

99/105

35/45

Euthyroid (%)

81

87

86

Hypothyroid (%)

3

6

11

Hyperthyroid (%)

16

7

3

P635 Clinical outcome of hyperthyroid patients affected by functional autonomy after individualized radioiodine treatment V. Longari, C. Canzi, M. Carletto, M. Castellani, P. Gerundini; Fondazione IRCCS Ospedale Maggiore, Milano, Italy. Objectives: Aim of this study was to evaluate the clinical outcome of patients affected by uni or multifocal autonomy of thyroid gland treated with an individualized radioiodine therapy in order to achieve euthyroidism. Methods: One hundred and eleven patients (age 66± 10; 79F and 32M) affected by uni (42%) or multifocal (58%) autonomy were studied. Before 131I therapy, patient accurate medical history was collected about hormonal status and previous treatments (percutaneous ethanol injections and/or antythyroid drug cycles). Each patient underwent a pretreatment dosimetric study to calculate the 131I activity to administer for therapy, based on repeated measurements of uptake (5 time-points) with a gammacamera after 123I administration. The same study was performed after therapeutic administration of 131I to calculate the real delivered dose. All treatments were as outpatients. Patients were antithyroid drug free for at least one month before dosimetry and therapy. Each patient was required to check the serum levels of TSH, FT3 and FT4 once a year after therapy. Results: The mean administered activity and the mean delivered target dose were 367± 130 MBq [range 111-600] and 146± 46 Gy [78-347] respectively. The mean follow-up was 3.1± 2.0 yrs with a maximum of 5 yrs, and more than 74% of patients for each follow up time point were monitored. An almost stable euthyroidism incidence rate of 85% was reached after the first year, while 13 patients became hypothyroid and 5 remained in a hyperthyroid status. No significant differences were found in the 3 groups of patients about the pre 131I treatment clinical status and previous treatments, as well as about the administered activities and target doses.Conclusions: Our clinical data showed that 131I activities and target doses lower than those reported in the literature may be administered to obtain excellent clinical outcome in patients with uni or multifocal thyroid autonomy. Few unsuccessful treatments were observed and no significant differences in pretreatment conditions or administered doses were found in comparison with euthyroid patients.

P50 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Endocrinology 2 P636 The prognostic value of SUV in patients with recurrent or metastatic thyroid carcinoma m. urhan1, g. acikgoz2, a. mavi2, a. alavi2, s. J. mandel2; 1GATA Haydarpasa Training Hospital, Istanbul, Turkey, 2the hospital of university of pennsylvania, Philadelphia, PA, United States. Introduction: A correlation between the degree of FDG uptake of the lesion sites and differentiation process of the thyroid tumor has been reported recently. In this study, we investigated the relationship between the prognosis and the SUV values of the recurrent or metastatic lesions in thyroid carcinoma patients.Materials and Methods: Twenty-two thyroid carcinoma patients (papillary in 20 and follicular in 2 patients) have been followed for a period of 4 years. The prognosis was classified as good, intermediate and poor regarding the recurrent or metastatic disease during the surveillance period.Results: In 9 patients with an SUV value of 3.1 to 28.5, the persistent disease was revealed with anatomical or functional imaging modalities and the serum thyrglobulin levels were elevated (range 9.3-69 ng/ml; median 22). In 10 patients with a negative FDG PET scan and SUV values less than 2, the recurrent or metastatic disease site was not detected and serum thyroglobulin levels ranged between 0.2 to 2 ng/ml. No disease site was revealed by imaging modalities despite an increase in serum thyroglobulin measurements in 3 patients and those group of patients were classified in the intermediate category.Conclusions: The recurrent and metastatic thyroid carcinoma patients with an increased SUV values should be managed more aggressively because it seems that the increased FDG uptake in the lesion sites appears to be a sign of poor prognosis.

P637 Pre-treatment preparation of patients with differentiated thyroid carcinoma within three weeks

M. Saghari, K. Ansari-Gilani, B. Fallahi, D. Beiki, A. Fard-Esfahani, M. Eftekhari; Research Institute For Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of). Aim: Ideal preparation of patients with surgically-resected differentiated thyroid carcinoma (DTC) is relied on optimally elevated serum thyroid stimulating hormone (TSH) to a value more than 30 µIU/ml. The aim of this study was to find the minimum time required to achieve optimum TSH level after discontinuation of levothyroxine or after total thyroidectomy.Materials and Methods: Fifty eight patients with DTC (14 male and 44 female) who had undergone total thyroidectomy and were planned for follow-up assessment or additional treatment entered in our prospective study. The patients had either a history of ablation with 131I in whom levothyroxin was discontinued without additional liothironine (T3) supplemetation (group 1, n=40), or had undergone a recent thyroidectomy without any ablative or supplementary treatment (group 2, n=18). For each patient serial weekly TSH measurements were carried out for up to six weeks or till adequate TSH elevation was achieved.Results: There is no difference in the mean time to achieve optimum TSH level in group 1 and group 2 (20.2 ± 6.7 days vs. 17 ± 5.6 days, p=0.134). Six patients (10.3%) failed to show adequate TSH elevation even after six weeks (two in group 1 and four in group 2). In 40 patients of the group 1, adequate rise in TSH was seen in 2(5%), 6(15%), 22 (55%), 4(10%) and 4(10%) in the first, second, third, fourth and fifth week of evaluation, respectively. In 18 patients of the group 2, reaching optimum TSH occured in 0(0%), 4(22.2%), 8 (44.4%), 2(11.1%) and 0(0%) in the first, second, third, fourth and fifth week of the assessment, respectively. Thus in general, 44 patients (75.8%) showed adequate rise in TSH within three weeks. Six of the remaining 14 patients (42.8%, 12.4% of total) never reached adequate TSH even by the end of the sixth week. Only in 8 of 14 patients (57.1%, 13.7% of total) TSH was optimally elevated after three weeks.Conclusions: In most patients with DTC being prepared for follow-up assessments or candidated for treatment with 131I, optimal serum TSH can be achieved within three weeks of operation or levothyroxin discontinuation. Only in a small number of patients, continuing serial TSH measurements after the third week was useful and in most cases, waiting after this time seems not to be of significant additional benefit. This is especially true for the group of patients who are to be prepared for ablation after recent thyroidectomy.

P638 Suppresive L-thyroxine therapy influence on bone mineral density in patients with thyroid carcionoma: longitudinal study results Z. Jurasinovic, M. Despot, S. Kusacic-Kuna, D. Dodig; Clinical Hospital Centre Zagreb, Zagreb, Croatia. The aim of our prospective study was to evaluate the influence of L-thyroxine therapy in suppressive doses on bone mineral density. It has been argued that this therapy, due to elevated levels of thyroxine (T4) and suppressed levels of thyrotropin (TSH), lead to accelerated bone turnover and mineral loss, just like thyrotoxicosis is well known risk factor for the development of secondary osteoporosis. From 2000 to the end of 2005 we monitored 81 female patients (age 21 to 75, median age 48) operated for differentiated thyroid carcinoma. One month after total thyroidectomy dual energy x-ray apsorptiometry (DEXA) of the lumbar spine and total hip region was performed and was used as baseline study. Ablative dose of 131I was then administered and L-thyroxine suppressive therapy initiated. Most of the patients were taking 150 µg of L-thyroxine (65 patients, 80%), and for the rest the dose had to be adjusted in order to achieve TSH suppression. The average T4 level in our group was 174,5 nmol/L, range 110,6 to 272,7 nmol/L. Control apsorptiometry was performed at least two years after the suppressive therapy had been started, but a number of patients had control exams after up to five years. In order to be able to compare control measurements that were done after different number of years, all control results were normalized to two years period. Statistical analysis using t-test for groups with equal variances was performed comparing Z-scores of the initial and control densitometry of the whole group, and no statistically significant differences were found (for the lumbar spine p=0,19556, for the total hip p=0,31540). We repeated the same statistical analysis for the subgroup of postmenopausal women (41 patient, age 44 to 75, median age 55), and again found no differences for the initial and control Z-scores (for the lumbar spine p=0,29592, for the total hip p=0,34981). We concluded that long-term suppressive therapy with L-thyroxine in patients with differentiated thyroid carcinoma after total thyroidectomy and radioiodine ablation is safe and that it doesn’t affect bone mineral density.

P639 Association between Hashimoto thyroiditis and thyroid cancer V. Voliotopoulos, C. Antypas, E. Pantelis, A. Filou-Giougi, I. Valais, A. Stavraka-Kakavaki; Iatropolis Magnitiki Tomografia S.A, Athens, Greece. Purpose:Hashimoto thyroriditis is a medical disease witch affects more than 5% of the population and rappresents the most common cause of hypothyoidism.The aim of the study is to evaluate the frequency of hasimoto thyroiditis in the differentiated cancer therefor the association between them. Methods and Materials:In 200 patients who received iodine 131 therapy in our department last year (71% with papillary and the rest with follicular carcinoma) 50(25%) had Hashimoto thyroiditis ,based in the cytological analysis of the surgical resect thyroid gland.Results: The association between Hashimoto thyroiditis and thyroid cancer is confirmed not only with the above findings but even from the bibliography.Conclusions: An adeguate follow up of the patients with hasimoto thyroiditis may permit an early diagnosis of differentiated thyroid cancer and its appropriate managment.

P640 Thyroid cancer and ablative radioiodine treatment after rhTSH stimulation : when serum thyroglobulin level be evaluated ? O. Morel, S. Girault, C. Berthelot, P. Giraud, C. Jeanguillaume, P. Jallet; Centre Paul Papin, Angers, France.

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Poster Presentation

delivered dose was 146± 46Gy [78-347]. Mean follow up was 3.1± 2.0 yrs with a maximum of 5 yrs and more than 74% of pts for each follow up time point was monitored. Results: Clinical conditions following therapy at different follow up time points are reported in the table. Eightyone percent of patients was cured within 6 months. Among the remaining patients with persistent hyperfunction of thyroid gland 46% became euthyroid within a year after the treatment. The latest resolutions of hyperthyroidism were observed up to 3 yrs. Conclusions: Although the retreatment of hyperthyroidism is mandatory after unsuccessful 131I therapy, a late normalization of thyroid function is not uncommon. Our data suggest that a second 131I dose should be administered at least one year after the first treatment.

Background: Thyroidectomy followed by ablative radioiodine therapy after L-T4 withdrawal is the treatment of choice for differentiated thyroid cancer (DTC). Just before 131-I administration, an elevated serum thyroglobulin (Tg) has been reported to correlate with persistent disease. In the follow-up of DTC, rhTSH-stimulated Tg level measurement is widely used and should be performed 3 days after the second rhTSH injection (Thyrogen, Genzyme Co). The Aim of the study was to evaluate Tg level change off L-T4 two days after I-131 administration.Methods: Fifty-five patients operated for DTC (49 papillary, 6 follicular) were treated by 131-I therapy off L-T4. Serum Tg was measured just before (TgD0) and 2 days after (TgD2) 3.7 GBq 131-I administration.Results: Mean TgD0 was 20.1± 59.4 ng/ml (range, 0-406) and mean TgD2 was 95.9± 132.1 ng/ml (range, 0-500). TgD2/TgD0 ratio was calculated for the 49 patients with detectable TgD0 (> 0.2 ng/ml) and was equal to 17.6± 23.5 (range, 0.7-108). For the 6 patients with undetectable TgD0, TgD2 was 10.4± 10.9 (range, 0-27.9).Conclusions: Two days after 131I ablative dose administration, high increase in serum Tg level occurs in most patients, even in those with undetectable TgD0 level. This increase is explained by 131-I uptake in residual thyroid tissue and radiation-induced cellular damage. So, if ablative radioiodine treatment is performed after rhTSH stimulation, Tg level measurement 3 days after the second Thyrogen injection (TgD2) is probably not significant. By contrast, it will be interesting to determine the significance of the TgD0 prognostic value.

P641 Lithium as adjuvant to radioiodine therapy in thyroid cancer treatment M. P. Stokkel, Y. Y. Liu, A. M. Pereira, H. A. Romijn, J. W. A. Smit; LUMC, Leiden, The Netherlands. Aim: Lithium has been reported to increase the radioiodine (I-131) uptake in benign thyroid disease and differentiated thyroid carcinoma (DTC). Currently, however, it is not known if lithium influences the clinical outcome of I-131 therapy in DTC. Therefore, we studied the clinical effects of I-131 without and with lithium in patients with proven metastatic DTC.Materials and Methods: 12 patients were selected with metastatic DTC who had previous I131 therapy without litium (control study) that had not influenced tumor progression, despite I131 uptake in the metastases. The patients were put on 1200 mg lithiumcarbonate/day followed by 6000 MBq I-131. The lithium was continued during 7 days after I-131 administration. A low iodide diet was started 1 week prior to I-131 therapy. Outcome parameters were I-131 uptake, serum Tg levels and radiologically dimensions of metastases as compared between the control study and the study with lithium.Results: The control I-131 therapy and I-131 therapy with lithium were not different with regard to serum TSH and Tg levels during T4 withdrawal. All 12 patients had lithium levels > 0.6 mmol/L. Uptake of I-131 was increased after lithium in 7 patients, decreased in 3 and was stable in 2. Radiological evaluation demonstrated tumor progression in 9 out 12 patients after Lithium. In 2 patients regression was seen.Conclusions: Despite the increased uptake of I-131 in 7 out of 12 patients with DTC no beneficial effect on I131 therapy with Lithium was observed on the clinical course as assessed by serum Tg levels and radiography. Therefore, the clinical value of lithium in DTC remains subject of debate.

P642 Mrd1, mpr and lpr in patients with untreated acute leukemia: correlation with tc-99m mibi scintigraphy I. Ak1, G. Demirel2, Z. Gulbas2; 1Osmangazi University Medical Faculty Department of Nuclear Medicine, Eskisehır, Turkey, 2Osmangazi University Medical Faculty Department of Haematology, Eskisehır, Turkey. We assessed the bone marrow uptake of Tc-99m MIBI and its correlation with messenger RNA (mRNA) levels of MDR1, Multidrug-Resistance Associated protein (MRP) and Lung Resistance Protein (LRP) in acute leukaemia.Methods: A total of 126 patients with new diagnosed acute leukaemia (18 ALL and 18 ANLL) were included the in the study. The expression of MRD1, MRPR, and LRPR on RNA levels were assessed the bone marrow samples. Planar images of the pelvis and thorax were acquired 20 min after injection of 740 MBq Tc-99m MIBI. The MIBI uptake in the bone marrow was evaluated using a quantitative scoring system with determination of the tumour-to-background ratios for the bone marrow in areas that included the proximal femur, anterior iliac crest and sternum. The correlation between the RT-PCR results and MIBI uptakes was analysed by using Spearman's rank correlation coefficients with two-tailed test of significance.Results: There was an reverse relationship between Tc-99m MIBI uptake of bone marrow and both RNA levels of MDR1 and MRP (p=0.001, r= - 733 and p=0.001, r= - 610, respectively). Correlation was not found between MIBI uptake and RNA levels of LRPP. Conclusion: Increased expression of MDR1 and MRPR correlates with a low accumulation of Tc-99m MIBI in bone marrow areas in patients with acute leukaemia.

P643 Comparison of co-registered dual phase 99mTc sestamibi SPECT imaging with ultrasound (US) in planning surgical access in primary hyperparathyroidism (pHPT) M. J. Carroll, K. Schulte, M. Y. Wong, M. Buxton-Thomas; Kings College Hospital, London, United Kingdom. Aims: The objective of this study was to compare co-registered early and late 99mTc sestamibi washout SPECT imaging with US for the localisation of parathyroid adenomas in patients with pHPT prior to surgery.Methods: 68 Patients underwent double phase parathyroid planar and SPECT sequential acquisitions at 20 minutes and 4 hours post injection of 600 MBq 99m Tcsestamibi.Early and delayed tomographic sections were co-registered using mutual information and displayed using the Hermes Volume Fusion Display utility.Results: 32 patients have had surgery. 19 patients are awaiting surgery. Of 32, 18 had a solitary adenoma and 16 had pluriglandular disease. Sestamibi imaging was positive in 28 patients and negative in 4. 23 patients had a single focus of activity on imaging, Of these 23, 19 patients were surgically confirmed as having a single adenoma, giving a PPV of 83%, imaging correctly lateralising the gland in 20patients, giving a PPV of 87%. Imaging correctly localised the gland exactly in 16 patients giving a PPV 70%. 5 patients were found to have multi- focus activity on imaging. Of these, 6 adenomas confirmed at surgery were laterilised correctly. There were additional 4 false

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positives seen on imaging, giving a PPV of 60%. US was positive in 14 patients and negative in 6. 11 did not have US performed. 13 patients had a single focus of activity on US.Out of these 13, 9 patients were surgically confirmed as having single adenoma, a PPV of 69%. Of these 13, imaging correctly localised the gland to the correct side of the neck in 9, a PPV of 69%. Ultrasound correctly localised the gland exactly in 6 patients giving a PPV 46%. 1 patient was found to have multi- focus activity on ultrasound and the adenomas were localised exactly. The presence of Adenomas was missed in six patients, four single foci, and 2 with pluriglandilar disease. Conclusion Co-registered two-phase tomographic imaging is effective in predicting and laterilising the presence of single gland hyperparathroidism, PPV of 83% and 87% respectively. This level of accuracy is essential for targeted surgery. The presence of multiple foci is highly predictive of pluriglandualar disease hence setting the scene for bilateral surgical exploration. This technique is less effective in pluriglandular disease , PPV = 60%. Comparing these results with US there is an increase in PPV in both prediction and localisation of a single focus by 14 % and 18 % respectively.

P644 Localization of parathyroid adenomas with tc-99m mibi imaging; relationship with p-glycoprotein expression, oxyphilic cell content and tumoral tissue volume B. Turgut1, S. Elagoz2, T. Erselcan1, A. Koyuncu3, S. Dokmetas4, Z. Hasbek1, S. Ozdemir1; 1Cumhuriyet Univ. School of Medicine, Dept. of Nuclear Medicine, Sivas, Turkey, 2Cumhuriyet Univ. School of Medicine, Dept. of Pathology, Sivas, Turkey, 3Cumhuriyet Univ. School of Medicine, Dept. of General Surgery, Sivas, Turkey, 4Cumhuriyet Univ. School of Medicine, Dept. of Endocrinology, Sivas, Turkey. In literature, in addition to tumor size, it has been suggested that, P-glycoprotein (P-gp) expression and/or oxyphilic cell content in parathyroid adenomas has an important influence on the results of Tc-99m MIBI parathyroid imaging. Aim: In this study we compared the results of MIBI parathyroid imaging and immunohistochemical analysis (IHA) of P-gp expression, oxyphilic cell content and tumoral tissue volume in parathyroid adenomas. We also evaluated the relationship between MIBI results and US results, operation results, serum biochemical values.Materials and Methods: Thirtysix patients (33F and 3M, mean age: 53.1±8.5yrs) with primary hyperparathyroidism who had undergone surgery were included in this study. Preoperatively, “dual phase” parathyroid scintigraphy with Tc-99m MIBI (including imaging of the neck and mediastinum) was performed in all patients. Thirty of the patients had also neck ultrasound (US). Serum parathormon (PTH), calcium (Ca), phosphorus (P), alkaline phosphatase (ALP) levels were measured preoperatively. In resected parathyroid tissues, P-gp expression and percentage of oxyphilic cell content were analyzed with IHA in 30 patients.Results: Three of the resected parathyroid tissues were hyperplastic parathyroid tissue, while 27 of the tissues were parathyroid adenoma (mean volume: 2.08±2.0ml). In Tc-99m MIBI parathyroid scintigraphy 72% of the parathyroid adenoma/hiperplastic parathyroid tissue was detected in correct localization, in US, this rate was 50%. According to the resected parathyroid tissue localization in surgery; sensitivity, accuracy, positive predictive value and prevalence in scintigraphy were 86.6%, 72%, 81%, and 83%, respectively. Those were, 62.5%, 50%, 71.4% and 80% for US, respectively. No significant correlation, but weak concordance was found between MIBI and US results (kappa:-0.20, p:0.23). Interestingly, significant correlation was found between tumoral volume and ALP level (r=0.41, p=0.015) and between PTH and ALP levels (r=0.72, p<0.001). In 21 of 30 patients MIBI was positive and 13 of these patients (62%) P-gp expression was positive. When histopathological results and MIBI results were compared; there was no significant correlation and concordance between P-gp expression (kappa=0.15, p=0.34), oxyphilic cell content (r=-0.1, p=0.63), tumoral tissue volume (r=-0.23, p=0.16). In 11 of 18 patients (61%) who had parathyroid tissue <1ml and in 13 of 20 patients (65%) who had oxyphilic cell content <10%, lesions were also detected correctly with MIBI scintigraphy. Conclusion: Present study results suggest that, MIBI scintigraphy was clearly superior to US as a diagnostic tool. However, P-gp expression, oxyphilic cell content and tumoral volume may have not a main effect on MIBI parathyroid scintigraphy results in parathyroid adenoma.

P645 Preoperative Parathyroid scintigraphy in secondary hyperparathyroidism; effect of vitamin D-analogue treatment on MIBI uptake and retention? A. K. Arveschoug; Department of Nuclear medicine, Århus University Hospital, Aalborg, Denmark. Aim: The sestamibi (MIBI) uptake and degree of retention plays an important role in the ability of the parathyroid scintigraphy (PS) to localize diseased glands correctly before surgery. Few studies show enhanced washout during treatment with vitamin D-analogues (Alfa -calcidol, Etalpha). A large proportion of patients with secondary Hyperparathyroidism (sHPT) receive treatment with Etalpha, so it seems important to evaluate the possible effect of this pharmaceutical on the PS.Materials and Methods: From 2000 to 2005 twenty-five patients (13 males, 12 females, average age 47, range 27-79 years) with sHPT, on the basis of chronic renal failure, where scanned and subsequently operated. Some patients were scanned before repeat surgery. Our PS includes early and late imaging with High Resolution parallel hole- and pinhole collimators, the last mentioned in anterior, left and right anterior oblique projections. Most patients also had a pertechnetate-thyroidscintigraphy performed. All patients where operated using the bilateral approach. All images where re-evaluated in regard to number of foci with uptake of MIBI on the early images and retention or washout of MIBI on the late images. The number of parathyroid glands with uptake, retention and washout were noted in the both patient groups i.e. receiving and not receiving vitamin D treatment. The level of parathyroid hormone (PTH) and plasma albumin adjusted calcium (p-alb.adj Ca) and total calcium concentrations as well as plasma phosphate at the time of PS where included.Results: Sixteen patients where on vitamin-D analogue treatment at the time of PS. Nine did not receive vitamin D. A total amount of 86 hyperplasic parathyroid glands was removed at surgery. The salient results are shown in the table below.

hyperplasia in 2. Abnormal gland localization was eutopic in 32 patients and ectopic in 8 (4 cervical, 2 mediastinal and 2 cervico-mediastinal).Conclusions. In our experience preoperative localization and radioguided surgery using 99mTc-MIBI are useful methods in the diagnosis and treatment of patients diagnosed with primary hyperparathyroidism. MIBI-SPECT scintigraphy has a higher sensitivity that MRI in this group of patients.

Vitamin D treatment

no vitamin D treatment

Glands removed at surgery (no.)

57

29

Glands with MIBI uptake (no. / %)

40 (70)

18 (62)

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Glands with MIBI retention (no. / %)

35 (88)

17 (94)

Glands with MIBI washout (no. / %)

5 (12)

1 (6)

The evaluation of tc-99m mibi and tc-99m tetrofosmin uptake in thyroid and parathyroid glands

serum-PTH ( Mean ± SD) pmol/L

117 ± 57

120 ± 69

p-alb.adj. Ca (mean ± SD) mmol/L

2,63 ± 0,21

2,72 ± 0,12

P646 Clinical evaluation of iterative versus analytic reconstruction for parathyroid lesions vizualisation in primary hyperparathyroidism with 99mTc-MIBI pinhole SPECT C. Ansquer1, E. Mirallié1, A. Oudoux1, C. Bodet-Milin1, M. Defrise2, A. Seret3, F. Kraeber-Bodéré1, T. Carlier1; 1University hospital, Nantes, France, 2University of Brussels, Brussels, Belgium, 3University of Liège, Liège, Belgium. Objectives: This study was aimed at assessing the clinical impact of using either iterative or analytic reconstruction algorithm after 99mTc-MIBI pinhole SPECT imaging (pSPECT) for the preoperative localization of parathyroid lesions (PL) in primary hyperparathyroidism.Methods: Twenty seven patients (22 F, 5 M, median age: 55 yrs), all cured after surgery, underwent pSPECT 60 min after injection of 925 MBq of 99mTc-MIBI. Projections were reconstructed with 2 methods, the filtered back-projection of Feldkamp (FDK) and a dedicated OS-EM algorithm (pOSEM). The volume reconstructed by the FDK method was post-filtered by a gaussian blurring (FWHM=5.5 mm) to insure approximately the same level of noise (defined as mean count divided by standard deviation on a uniformly region of interest) than the pOSEM reconstruction. The two series of pSPECT were analyzed independently by two blinded nuclear medicine specialists to determine the sensitivity of lesions detection. A diagnostic confidence score (CS) was assigned for each exam considering intensity and extra-thyroidal location of each suspected lesion. This CS was defined as follows: 0= negative, 1= doubtful, 2= moderately positive, 3= positive. Then, the 2 series of images were compared visually to determine the global difference of quality. The qualitative index (QI) was chosen to score the difference was defined as follow: 0= no difference, 1= moderate difference, 2= large difference.Results: Surgery revealed 30 PL (median weight 0.5 g), 5 in posterior and 2 in minor inferior ectopy. Sensitivity of detection were of PL were 93% for FDK and pOSEM. The same hyperplastic glands (0.1 and 0.2g) were not detected by the 2 methods. The CS were similar with the 2 algorithms for 28/30 PL and slightly lower with FDK (3 vs 2 with pOSEM) for two PL. As far as the qualitative index was concerned, the amount of noise in FDK reconstructed volumes was superior to that found in pOSEM images and the contour of thyroid were generally less delimited with FDK. There was no significant difference of QI for 7/27 patients (26%) and a moderate or large difference for 20/27 patients (74%). A poor thyroid uptake was found to affect quality of the two series of pSPECT.Conclusions: Although, no significant clinical difference was found in the ability to visualize parathyroid ; pOSEM reconstruction give less noisy images and should be preferred to FDK reconstruction, especially when a poor residual thyroid uptake is found.

P647 Preoperative localization and radioguided surgery of primary hyperparathyroidism using 99mTc-MIBI scintigraphy and hand-held gamma probe. A. Tardín, E. Prats, P. Razola, J. Deus, M. Martinez, F. Garcia, M. D. Abos, J. Banzo; University Hospital, Zaragoza, Spain. The aim of this study was to evaluate the role of 99mTc-MIBI scintigraphy and hand-held gamma probe in the localization and radioguided resection of parathyroid adenoma or hyperplasia in patients with primary hyperparathyroidism. Methods. We performed radioguided surgery using a low-dose 99mTc-MIBI protocol in 40 patients (36 female and 4 male, age range 35-79) diagnosed of primary hyperparathyroidism. All patients presented a positive preoperative dual-phase MIBI scintigraphy, including SPECT images. In all of them we evaluated the uptake pattern of the abnormal gland according to their presentation on the dual-phase study. In 16 patients a MRI was also performed. In the day of the surgery a low-dose of 99mTc-MIBI was administrated to the patient. The interval between injection and surgery was determined according to the results of the dual-phase MIBI scintigraphy. The gamma-probe was used in order to guide the parathyroidectomy. Intraoperative PTH determination and pathological evaluation were done in all cases. A positive pathological result, a descent in the PTH values higher than 60% and a counting rate higher than 20% between adenoma/hyperplasia and thyroid background were criteria used to determine the successful excision of the abnormal gland. Results. In 16 patients the abnormal gland was better visualized in early images, in 11 in late images, whereas in 13 there was no significant differences. Although dual-phase scintigraphy was positive in all cases, 2 parathyroid adenomas were detected only in early images and 2 in late images. RMI study was positive in 11 patients and normal in 5 (sensitivity 68,7%). Radioguided intraoperative localization and resection was achieved in all patients. In all cases descent in PTH values was > 60% (range 75-95%) and abnormal gland activity was > 20% than thyroid background activity (range 20-400%). Pathological diagnosis was adenoma in 38 patients and

Aim: Tc-99m MIBI and Tc-99m tetrofosmin are used agents in thyroid and parathyroid imaging. The early and late uptake of the agent may explain its performance to detect the parathyroid lesion. The purpose of this study is to evaluate the uptake of Tc-99m MIBI and Tc-99m tetrofosmin in thyroid and parathyroid gland.Materials and Methods: Twenty-four patients (21 female, 3 male; aged 47.45 years, range 19 to 93) with the suspicion of parathyroid adenomas were included in this study. Tc-99m pertechnetate thyroid scintigraphy, Tc-99m MIBI and Tc99m tetrofosmin parathyroid scintigraphies were performed on different days. Regions of interests (ROI) were genereted over the area of parathyroid lesion, normal thyroid tissue and background. The mean count (mc) in each ROI was determined on early (E) and delayed (D) images. Early and delayed thyroid/background (T/B) ratio and parathyroid/ background (P/B) ratio were determined. The washout rate for Tc-99m MIBI and Tc-99m tetrofosmin were calculated and the results were compared.Results: The T/B ratio of Tc-99m pertechnetate (12.20±5.68) was significantly higher than the early T/B ratios of Tc-99m MIBI and Tc-99m tetrofosmin (p< 0.001). The E T/B and D T/B ratio of Tc-99m MIBI and Tc-99m tetrofosmin were 4.28±1.35, 2.34±1.07 and 3.82±1.16, 2.94±1.20, respectively (p<0.05). The washout rate of Tc-99m MIBI and Tc-99m tetrofosmin were 45.48±12.23 % and 25.24±14.95 %, respectively (p<0.001). Eight cases were interpreted as positive for parathyroid adenoma. The E PT/B and D PT/B ratio of Tc-99m MIBI and Tc-99m tetrofosmin were 3.71±1.02, 2.21±0.62 and 3.13±0.88, 2.06±0.73, respectively.Conclusions: We found that Tc-99m tetrofosmin shows a lower early thyroid uptake and a higher retention compared with Tc-99m MIBI. The early uptake of Tc-99m tetrofosmin in adenoma is significantly lower than Tc-99m MIBI. Although the uptake of Tc99m MIBI and tetrofosmin in adenoma are sufficient for the detection, the lower washout rate and lower early uptake of tetrofosmin in adenoma may cause interpretation pitfalls in parathyroid imaging.

P649 The importance of oblique views in locating deeply situated parathyroid glands (PGs) using sestamibi parathyroid scintigraphy T. Athanasoulis, D. Tamanidi, V. Skalistis, T. Karianos, P. Jiannakopoulou, C. Palestidis, C. Zerva; 'Alexandra' University Hospital, Athens, Greece. Surgical removal of deeply situated PGs is more difficult and obviously more precise localization should be very useful in planning the surgical procedure. The aim of the study was the evaluation of the oblique sestamibi imaging in determining more accurately the depth of the identified PDs. Material and methods. In this retrospective study 255 consecutive patients who had a positive scan (190 with primary and 65 with secondary hyperparathyroidism) were included. A double phase sestamibi technique followed by a pertechnetate scan was used. Early right and left 30 degree images were routinely obtained. Findings were classified in to two groups based on the degree of change of the relative position of PGs and thyroid gland (TG) in the oblique compared with the anterior image. Group I included PGs where the relative position of PG and TG in the anterior and oblique images remained the same or only slightly changed (increasing mildly the PG to TG distance). Those PGs were characterized as not deeply located and could be behind but close to TG, or infrequently totally or partially intrathyroidal, or anteriorly located when they were outside TG margin. Group II included PGs that in oblique images the PG to TG distance was significantly increased and were characterized as deeply located. Results A total of 338 PGs were identified ( 34 upper right, 74 upper left, 128 lower right and 102 lower left). Group I included 30/34 upper right PGs, 60/74 upper left, 104/128 lower right, and 95/102 lower left (289 of the total 338 PGs). Group II included 4/34 upper right PGs, 14/74 upper left, 24/128 lower right, and 7/102 lower left (49 of the total 338 PGs). Upper left and lower right were significantly more frequently located at a significant depth compared with the opposite site (p<0,05 and p<0,01 respectively). Comparing these results with the available surgical data the depth of all PGs of the I and II groups were correctly estimated. Conclusion These results indicate that oblique images can estimate successfully the depth of deeply located PGs allowing better surgical planning and better selection of patients for minimal invasive surgery.

P650 Serum leptin levels related to bone mineral density in HIV patients treated with highly active antiretroviral therapy (HAART) G. Madeddu1, A. Spanu2, P. Solinas2, G. M. Calia1, C. Lovigu1, M. Mannazzu1, F. Chessa2, A. Falchi2, M. S. Mura1, G. Madeddu2; 1Dept of Infectious Diseases, University of Sassari, Sassari, Italy, 2Dept of Nuclear Medicine, University of Sassari, Sassari, Italy. Aim: Experimental studies have identified Leptin (Lp) as a potent inhibitor of bone formation. We investigated whether a relationship between Lp and bone mass loss exists in HIV pts treated with HAART.Methods: We enrolled 108 HIV pts on HAART, 65 M and 43 F, and 40 normal controls (C), 15 M and 25 F, all with normal body mass index values (range 18-25). In all pts and in C we measured whole body BMD (g/cm2) by DEXA and we calculated T-score, subdividing the pts according WHO: with low T-score (<-1;L) and with normal T-score (• -1;N). We further subdivided L pts in osteopenic (T-score: between -1 to -2.5) and osteoporotic (T-score: < -2.5).

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Poster Presentation

Using Chi-square test, Fishers exact test and test on two independent proportions for proportion with uptake and proportions with retention in the two groups i.e., with and without vitamin D treatment, there was no differences. There were no significant differences between the levels of PTH and calcium or phosphate parameters in the two groups of patientsConclusions: In this small population of patients with sHPT no effect of vitamin-D analogue treatment on the uptake and retention of MIBI could be found.

S. Turkolmez, E. Ozdemir, D. Cayir, K. Demirel, G. Koca, M. Korkmaz; Ankara Training and Research Hospital, Ankara, Turkey.

Total body fat mass (TFM; g) and percent fat (%) were also measured. Moreover, we assayed in serum Lp (ng/ml) by RIA, Osteocalcin (O) and Bone Alkaline Phosphatase (BAP) by IRMA, and in urine Pyridinium Crosslinks (PYR) by ELISA.Results: Thirty-two/65M and 16/28 F HIV pts were L, BMD being 0.99±0.06 and 0.96±0.05, respectively, significantly (p<0.01) lower than in N pts (1.13±0.04 and 1.09±0.1, respectively); 26/32 M and 14/15 F of L were osteopenic, the remaining 6/32 M and 1/15 F were osteoporotic. Mean TFM and percent fat values, O, BAP and PYR levels were higher in L than in N pts; however, the difference was significant for TFM (p<0.03) and percent fat (p<0.004) values only in M. Mean Lp values were higher in L than in N pts, but the difference was significant only for M (3.2±1.7 vs 2.3±1.0; p<0.005). In the latter pts, Lp was higher only in osteoporotic (4.4±2.2) than in osteopenic (2.9±1.4; p<0.04) pts; moreover, Lp was higher only in osteoporotic pts in respect of C (4.0±2.3), but non significantly. Only in M of both L and N groups, Lp positively correlated with TFM, percent fat, O and PYR, while negatively with BMD.Conclusions: An inverse relationship seems to exists between serum Lp and BMD in HIV pts treated with HAART, particularly in males. A combined Lp and HAART effect may be hypotesized in bone mass loss in these cases.

P651 Salivary gland functions in type 2 diabetic patient H. Kaya1, B. Kaya2, S. Altun Tuzcu3, A. Tuzcu4; 1Dicle University School of Medicine department of Nuclear Medicine, Diyarbakir, Turkey, 2Dicle University School of dentistry Department of Oral and Maxillofacial Surgery, Diyarbakir, Turkey, 3Dicle University School of Medicine Department of Nuclear Medicine, Diyarbakir, Turkey, 4Dicle University School of Medicine Department of Endocrinology, Diyarbakir, Turkey. Aim:To investigate salivary glands function in type 2 diabetic patient and its relationship with xerostomia .Materials and Methods: Twenty type 2 diabetic and 10 non-diabetic healthy subjects were included to the study. Gamma camera with general purpose collimator was used. Twenty mCi Tc 99m pertechnetate was injected intravenously and dynamic scintigraphic image was obtained every one minutes for thirty minutes. Fifteen minute after injection, saliva secretion was stimulated by giving lemon juice. Region of interest were drawn to the first, 15th and 17th minute images of major salivary glands and background (frontal region). First and 15th minute uptake ratio (UR) of salivary glands are calculated. Two minutes after stimulation of salivary glands (17th minute) excretion ratio of the glands were calculated. Colony counts of candida was collected from saliva samples (0.5cc)of two groups Independent-t test was used for comparison of two groups.Results: First minute UR of right and left parotis gland were significantly lower than control group (p<0.001, p<0.01, respectively), and first minute UR of left and right submandibular gland were lower than control group (p<0.05, p<0.001, respectively). UR of right and left parotis gland of 15th minute were significantly lower than control group (p<0.001). UR of left and right submandibular gland 15th minute were lower than control group (p<0.001). Mean excretion ratio of all glands in diabetic group was significantly lower than control group(p<0.05).Although there was a correlation between saliva function with oral candida colony counts, any statistical significant difference could not be determined (p>0.05).Conclusions: Salivary gland function of diabetic subject is lower than control group.

P652 High resolution scintigraphy in diagnosis and radioguided surgery of diabetic foot osteomyelitis G. Capriotti1, G. Di Santo1, C. D'Alessandria1, T. Lanzolla1, F. Di Stasio1, A. Anastasia1, R. Massari2, C. Trotta2, A. Soluri2, F. Scopinaro1; 1University "La Sapienza", Rome, Italy, 2Institute of Biomedical Engineering, ISIB-CNR, Rome, Rome, Italy. Aim: Osteomyelitis is a heavy complication of diabetic foot and its diagnosis requires an integrate approach, both for the clinicians and for the specialist imaging. Leukocytes scan (WBCS) plays a key role in the diagnosis of osteomyelitis. It is performed to reduce the number of amputation, to improve wound healing and to reduce the mortality of patients. The suboptimal spatial resolution of Anger cameras (AC) represents a limitation to achieve these goals. Some studies suggested the role of High Resolution Scintigraphy (HRS) in the diagnosis, radioguided surgery and biopsy of different diseases. Aim of present study is to verify if WBCS is able to improve the diagnosis of osteomyelitis and to help surgery with the use of an hand held High Resolution Detector (HRD),.Materials and Methods: 10 patients, mean age 64 yrs, with forefoot ulcers, were enrolled. In all patients planar X-ray, MRI and conventional 99mTc-HMPAO-WBCs were performed. 24h after administration of radiolabelled WBC, each patient was studied by HRS with HRD. The hand held HRD showed four inch2 FOV, 2 mm spatial resolution, 18% energy resolution. The patients underwent surgery or bone biopsy using HRS.Results: Three patients showed negative scan with both devices. They showed an ulcer without infection, debridement of lesion was sufficient to obtain healing (Table). Seven patients showed positive scan at AC without bone infection. HRD showed hot spots of radioactivity in the same patients. In four of them, the hot spot was bar-shaped. This bar-shaped radioactivity was considered as sign of osteomyelitis. One patient, with positive WBCs, refused surgery. Two patients, with positive scan and no sign of osteomyelitis at AC as well as at HRD underwent complete curettage of purulent inflammation using HRD during the surgical treatment. Two of the 4 patients showing infection at HRD were treated by amputation of the two distal phalanges of the toe because of osteomyelitis. The other patients underwent to radio-guided bone biopsy. Bone infection was confirmed by culture exam.Conclusions: HRD seems to be able to guide surgical treatment opening a new way in the therapy of infected foot. It is possible to assess if surgical removal of purulent inflammation is complete and to precisely guide biopsy or removal of the bone with osteomyelitis.

WBCs negative

WBCs positive without sign of osteomyelitis

Osteomyelitis

Anger Camera 3

7

0

HRD

3

3

4

Surgery

No Infection

2

4

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P653 The findings of quantitative salivary gland scintigraphy in patients with ankylosing spondylitis and rheumatoid arthritis K. Demirel1, M. Korkmaz1, D. Cayır1, S. Türkölmez1, E. Özdemir1, G. Koca1, B. Nacır2, R. Erdem2; 1Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey, 2Department of Physical Medicine and Rehabilitation, Ankara Training and Research Hospital, Ankara, Turkey. Aim: The aim of this study was compare te quantitative parameters of salivary gland scintigraphy in healthy volunteers and in patients with Ankylosing spondylitis (AS) and Rheumatoid arthritis (RA).Methods: 47 patients (30 with AS, 17 with RA) and 28 healthy controls participated in the study. There was no significant difference in baseline characteristics between patients and controls. Quantitative salivary gland scintigraphy were obtained in all of patients and healthy controls. After intravenous administration of 370 MBq Tc-99m pertechnetate, dynamic scintigraphy was performed for 50 minutes. Lemon juice stimulation was delivered at 40 min. Functional parameters for the parotid and submandibular glands were calculated. Statistical analysis was performed by using the Anova, Kruskal-Wallis and Mann-Whitney U test.Results: When compared with the control group, the maximum accumulation and time at maximum count of the parotid and submandibular glands significantly decreased in patients with AS and RA. The time interval from stimulation to minimum count of the submandibular glands increased significantly in patients with AS and RA. The uptake ratio of the parotid glands significantly decreased in patients with AS compared with healthy volunteers. Functional parameters of the parotid and submandibular glands did not differ significantly between AS and RA. There were no statistically significant sex or age differences in the evaluation of salivary function by scintigraphy. Conclusion: The likelihood of salivary glands dysfunction is relatively high in patients with AS and RA. The results demonstrated that quantitative salivary gland scintigraphy can be used to early detection of Sjögren’s syndrome in patients with AS and RA.

P51 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Gastroenterology 1 P654 Is Ethylcellulose capsule appropriate for colonic transit study? O. Savas1, M. Cabuk1, F. Sen1, L. Kirilmaz2, M. Asikoglu3, E. Cevher4; 1 Zonguldak Karamelmas University Faculty of Medicine, Department of Nuclear Medicine, Zonguldak, Turkey, 2Ege University, Faculty of Pharmacy, Department of Biopharmaceutics and Pharmacokinetics, Izmir, Turkey, 3Ege University, Faculty of Pharmacy, Department of Radiopharmacy, Izmir, Turkey, 4Istanbul University, Faculty of Pharmacy, Department of Biopharmaceutics and Pharmacokinetics, Istanbul, Turkey. Aim:Large bowel disorders are common, affecting up to 10% of the population. Constipation may be due to either a colonic motility disorder that shows the delivery of stool to the rectum or a defecation disorder that impairs the passage of out of the rectum. In recent years, studies of the colon and anorectum have been commonly employed to distinguish between these possibilities in the work up of constipation. Various methods of measuring colonic transit time are available. The aim of this study were to assess the utility of ethylcellulose capsule in vivo for colonic transit time. Colonic transit scintigraphy is a safe and noninvasive method for quantitative evaluation of overall and regional colonic transit. The isotope can be given orally in a nonabsorbable form together with test meal (radiolabeled mixed meal) , in a capsule coated with pH-sensitive material that dissolves in the colon or terminal ileum or encapsulated in nondigestive capsules. Using pH-sensitive capsule, permits delayed release of radioisotope and accurate calculation of transit across the colon from a single starting location and time. Materials and methods: We used ethylcellulose capsule, which was shown to be resistant in simulated gastric and intestinal media for 8 hours before, in our study. We labelled ion exchange resins with Ga-67 citrate and after vaporized to dryness, put the radiolabelled resins to ethylcellulose capsule. An healthy volunteer, overnight fast, ingested the capsule. Supine 1 minute anterior-posterior images were taken 2-4-6-8-12-24 hours after ingestion of capsule and after defecation by a large field of view gamma camera with medium energy collimator. Results: Throughout the in vivo study, the ethylcellulose capsule didn’t disintegrated, and after defecation we didn’t see any activity at the abdomen image.Conclusion: Ethylcellulose capsule was found to be resistant to gastric and bowel content in vivo for 24 hours and this made ethylcellulose capsule inappropriate for colonic transit study. Also this finding showed us that, scintigraphic methods are helpful to see behaviours of pharmaceutic forms in gastrointestinal tract.

P655 The significance of duodenogastric bile reflux seen during hepatobiliary scintigraphy M. Aydin, Y. Gumurdulu, A. F. Yapar, M. Reyhan, A. Sukan, E. Serin; Baskent University, Adana, Turkey. Aim: To evaluate the significance of duodenogastric bile reflux seen in the stomach during the hepatobiliary scintigraphy in comparison with endoscopic findings and histological examination.Materials and Methods: Fifty-one patients with dyspepsia were studied (35 female, 16 male; mean age 48 ± 11 yr with a range of 21-71 yr). All patients underwent hepatobiliary scintigraphy and upper gastrointestinal endoscopy. Hepatobiliary scintigraphy was performed after an intravenous injection of 185 MBq (5 mCi) Tc-99m mebrofenin using either single or dual-head gamma cameras (Diacam and E-cam, Siemens) equipped with parallel hole lowenergy general-purpose collimators. All patients were studied in the supine position. Continuous computer acquisition was performed at a rate of 1 minute/frame for 90 minutes. At 60 minutes after injection of radiotracer, each patient was asked for fatty meal to stimulate gallbladder

P656 Oesophageal scintigraphy in follow-up of achalasia during two years after pneumatic dilatation Z. Jankovic, D. Pucar, L. Jaukovic, B. Ajdinovic; Academy, Belgrade, Serbia and Montenegro.

Military Medical

Achalasia is a disorder of unknown cause that heavily affects oesophageal function. Therapeutic modalities include drug therapy, pneumatic dilatation (PD), botulinum toxin injection and surgical myotomy. PD is currently the method of choice for therapy of achalasia. Results of treatment can be evaluated by monitoring changes of patient symptoms and by use of radiographic, endoscopic, manometric and nuclear medicine methods. Oesophageal scintigraphy (OS) is an optimal method for disease follow-up and enables quantitative estimation of esophageal emptying. AIM. Evaluation of results of PD in patients with achalasia comparing the oesophageal emptying before and after therapy. PATIENTS and METHODS. 28 patients with achalasia were subjected to PD. Scintigraphy with 99m Tc pertechnetate was done before PD in all patients. All these patients had good clinical response to PD. 17 patients were examined by OS during first year after the procedure and 11 patients in the first and in the second year after PD. Radionuclide retention index (RI) was calculated as the ratio of counts over oesophagus and the sum of counts over the oesophagus and stomach obtained in upright position. RESULTS. The values of RI before therapy were 16.2-100% (mean value 66.4%). In patients followed one year the mean RI value during first six months was 8.9%, and during second six month period was 8.6% (the difference was not significant, p>0.05). In patients followed two years mean RI value was 7.8% (0.6-26.8%) in the first year, and 8.4% (2.6-20.0%) in the second (the difference was not significant, p>0.05). CONCLUSION. The results in the first and second year after treatment were similar indicating persistent long term effects of PD. The small increase of RI in the second year was not significant. The patients should be followed further to track changes of RI and to indicate need for additional therapy.

P657 Role of red blood cell scintigraphy in localization of gastrointestinal bleeding Y. Sanli1, I. Adalet1, C. Turkmen1, H. Tokmak1, M. Tamam1, S. Kuyumcu1, H. Yanar2, E. Balik2, S. Cantez1; 1Istanbul University, Istanbul Faculty of Medicine,Department of Nuclear Medicine, Istanbul, Turkey, 2Istanbul University, Istanbul Faculty of Medicine,Department of General Surgery, Istanbul, Turkey. Purpose: To evaluate the role of Tc-99m labeled RBC scintigraphy in the determination of the localization of the upper and lower gastrointestinal system (GIS) bleedings based on our clinical experience.Materials and Methods: In this retrospective study, a total of 57 cases (27 females, 30 males) (mean age of 43.9±24), referred from various clinics between 1995 and 2005 were evaluated for the determination of the localization of the GIS with RBC scintigraphy.Results: Of the 57 GIS bleeding scintigrams evaluated in this study, 31 (54.4%) were found to be positive, while 26 (45.6%) were found to be negative. Of the patients referred to our clinic, 23 had complaints of hematochesia, 34 were complaining of melena. The haemoglobin values of the patients were between 4,1-9,6 ml/dl and the mean haemoglobin level was calculated to be 7,3±1,2 ml/dl. Gastroscopy to 51 (89.4%), colonoscopy to 45 (78.9%) and angiography to nine (15.7%) of the patients were applied. The patients who were referred to our clinic, had at least one of these diagnostic examinations performed and the results of the examinations were interpreted either to be “normal” or “no bleeding focus of point could be found”. Regarding the medical histories, 10 patients were on steroids, 6 patients were on non-steroid anti-inflammatory drugs, two patients were on aspirin and one patient was on oral anti-coagulants. A total of 14 patients, of which nine were with a pre-diagnosis of lower GIS bleeding and five were with a pre-diagnosis of upper GIS bleeding (those, whose scintigrams were evaluated to be as lower GIS bleedings) were operated due to GIS bleedings. Operations of 13 patients confirmed the diagnosis of scintigraphic findings giving an accuracy of 92.8% for the scintigraphy technique. Of all patients, scintigrams were positive in the first hour with dynamic imaging in 19, first 4 hour static images in 7 and first 24 hours images in 5 patients. In these patients, ten patients were operated, 7 patients were treated medically and two patients died after obtaining positive scintigrafic findings within first one hour. Of 43 patients, who were not operated, the prediagnosis reported 29 patients to have upper and 14 patients to have lower GIS bleedings. In 17 members of this group, the scintigrams revealed positive results, while the other 26 had negative results.Conclusion: The present study revealed that, Tc-99m labeled RBC scan is more useful in lower GIS for detecting bleeding localization, compared with upper GIS.

P658 Quantitative Assessment of FDG Uptake in the Stomach K. M. Alkhawaldeh, S. Dadparvar, M. Houseni, G. Bural, W. Chamroonrat, G. El-Haddad, A. Alavi; Hospital of the University of Pennsylvania, Philadelphia, PA, United States.

Objectives: Stomach appearance in whole body FDG PET scan is variable and can range from absent to diffuse intense uptake. Our purpose was to study the possible factors that may affect FDG uptake in the stomach including: patient's age, blood glucose level, weight, gender, and dual time point imaging.Methods: One hundred eighty eight patients where included in this retrospective study (83males, 105 females, age range 8 - 87). All patients underwent whole body FDG PET scan and 40 patients had 2 sequential FDG PET scans (dual-time-point imaging): the first scan at 60 minutes after FDG injection and the second at 90 minutes after injection. Blood glucose level ranged from 75-160 mg/d at the time of FDG administration. For the sake of study of each factor, patients were divided into multiple groups according to age(<15 years, 16-30, 3145, 46-60 and >60 ) , according to blood glucose level at time of FDG injection( <140mg/dl and >140mg/dl), according to weight( <80kg and>80 kg) and according to gender (males and females). Quantitative assessment of FDG uptake in the stomach was performed using mean standardized uptake values (SUV) and the change in stomach SUV between time point 1 and time point 2 was calculated from dual time imaging.Results: Stomach SUV ranged from 0.8 to 4.5 with a mean of 2.11 + 0.68. Mean stomach SUV in patients less than 15 yeas of age was 1.16 + 0.09, which was significantly lower than mean stomach SUV in the older age groups (P< 0.05). Mean SUV values for older age groups ranged from 2.09+0.28 to 2.31+0.29 with no significant difference between those groups (p>0.05). There was no significant effect of blood glucose level ,patient's weight, gender, or delayed imaging(on dual time imaging) on stomach SUV values (P>0.05)Conclusions: There is significant lower stomach FDG uptake in the pediatric age group as compared to adult groups. Although there was no significant change in FDG stomach uptake throughout adult groups, our study didn't take in consideration the possible effects of diabetes mellitus which may have a significant effect. Blood glucose level within the range of 75- 160 mg/dl, weight, gender and delayed imaging did not show any significant effect on stomach FDG uptake.

P659 Gastric scintigraphy with a liquid meal in patients with gastroesophageal reflux disease and functional dyspepsia L. Dobrek1, A. Stepien2, J. Pawlus2, M. Nowakowski3, A. Sygula4, P. J. Thor1; 1Department of Pathophysiology, Jagiellonian University, Medical College, Cracow, Poland, 2Nuclear Medicine Department, 5th Clinical Military Hospital, Cracow, Poland, 33rd General Surgery Department, Jagiellonian University, Medical College, Cracow, Poland, 4Gastrointestinal Consulting Office, “Batory” Outpatient Clinics Unit, Cracow, Poland. INTRODUCTION: Gastric Emptying (GE) rate is impaired in both GastroEsophageal Reflux Disease (GERD) and Functional Dyspepsia (FD) patients. However, GERD patients can be divided into two subgroups: without any esophageal inflammatory changes (Non Erosive Reflux Disorder; NERD) and with esophagitis (Erosive Reflux Disorder; ERD). Similarly, FD population can be classified into ulcer-like (ULD), dysmotility-like (DLD) and non-specific (NSD) patients. There are few reports about GE research, taking into consideration this detailed division. AIM: The aim of our study was to estimate GE in patients with GERD and FD after standard liquid test meal using scintigraphy. MATheRIAL AND METHODS: We studied 14 GERD patients (age 52,3 ± 9,4) with typical acid reflux symptoms and 18 FD ones (age 49,2 ± 11,1). In the first stage, to make a precise GERD/FD diagnosis, we performed upper GI endoscopy, stationary esophageal manometry and 24-hour esophageal pH-metry monitoring. According to results of these studies and symptoms’ score questionnaires, we distinguished: 7 ERD pts, 7 NERD pts, 9 DLD pts and 9 NSD ones. We also selected age matched control group, containing 10 healthy volunteers (49,1 ± 8,0 yrs). Finally, all the studied participants underwent upper GI scintigraphy with estimation of gastric emptying rate, after 200ml test meal (Nutridrink), labelled with radioactive technet 99m in colloid sulphure. The gastric images were collected every 5 minutes for the 1,5 hour using gamma-camera with large field of vision. The analyzed parameter was mean gastric emptying half time - T50, expressed in [min]. Statistical analysis was made using Bartlett test.Results: We found difference between NERD and ERD pts71% and 43% of them had prolonged GE value (p < 0,05). In NERD group, mean T50 achieved 107 [min], in ERD group this value was 48 [min] vs control 35 [min], (p < 0,05). In FD population, delayed GE occurred in 55% NSD and in 75% DLD patients. The mean T50 was 77 [min] in DLD group and 54 [min] in NSD patients vs. 35 [min] in control (p < 0,05).Conclusions: Scintigraphic estimation of GE rate shows significant differences in studied groups. The most profound increase in GE was observed in NERD patients. ERD patients had only slightly GE rate delayed. In FD patients, GE particularly increased in DLD group. Our findings suggest that esophageal mucosal inflammation in the course of GERD accelerates GE rate, contrary to NERD and DLD.

P660 99m

99m

Evaluation of Tc-labeled red blood cells and classic Tcmebrofenin iminodiacetic acid cholescintigraphy in the detection and follow-up of hepatic fibrosis and cirrhosis V. Papantoniou1, P. Valsamaki1, S. Tsiouris1, N. Ptohis2, E. Sotiropoulou2, J. Koutsikos1, E. Stipsanelli1, M. Melissinou3, A. Daramaras1, G. Zaharakis4, I. Koskinas4, A. Archimandritis4, C. Zerva1; 1Department of Nuclear Medicine, ‘Alexandra’ University Hospital, Athens, Greece, 2Department of Radiology, ‘Alexandra’ University Hospital, Athens, Greece, 3Department of Internal Medicine, ‘Metropolitan’ Hospital, Athens, Greece, 4Department of Internal Medicine, ‘Hippocration’ University Hospital, Athens, Greece. Aim: Disturbance of the hepatic microvasculature may reflect the different stages of both liver fibrosis and cirrhosis. This study was designed to investigate the efficacy of 99mTc-labeled red blood cells (LRBC) in estimating these blood flow changes and discriminating early fibrotic from cirrhotic patients; comparison with 99mTc-mebrofenin iminodiacetic acid cholescintigraphy (CHS) was also performed.Materials and Methods: Twenty patients, 7 with fibrosis and 13 with cirrhosis, at stages A, B, or C, (according to CHILD PUGH classification) and 20 age-matched controls were submitted to LRBC and CHS at consecutive sessions (4-day time interval). Static images at 10 min were acquired with both methods. Semiquantitative analysis [liver-to-heart (L/H) ratio] was performed with regions of interest defined over the organs. L/H ratios by both scintigraphic methods were compared (T-test) between the fibrotic and cirrhotic patients versus

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Poster Presentation

contraction. Scintigraphic duodenogastric reflux was determined by visually and quantitatively as stomach activity divided by hepatobiliary activity. Edema, erythema, inflammation, erosions, ulcerations, and bile in the stomach were noted during endoscopy. When endoscopic findings of gastritis or bile were present, proximal antral biopsy specimens were obtained for histological evaluation. Comparisons between various groups were made using Pearson correlation coefficient.Results: Of the 51 patients studied, visual evidence of duodenogastric reflux was seen on dynamic images in 18 patients (35%). In quantitative analysis, the percent reflux ranged from 1% to 25%. Duodenogastric reflux as seen visually on scintigraphy correlated well with the degree of quantitative analysis (r=0.7). Bile in the stomach was observed in 19 patients (37%) undergoing upper endoscopy. Histological gastritis was determined in 24 patients (47%). We found no correlation between scintigraphic visualization of duodenogastric reflux and either histological changes or presence of bile at endoscopy; and histological confirmation is essential when bile reflux gastritis is suspected.Conclusions: Our findings revealed no correlation between duodenogastric reflux seen during hepatobiliary scintigraphy and histological gastritis or presence of bile in the stomach at endoscopy.

the control group, the different cirrhotic stages versus the control group, and fibrotic versus cirrhotic patients. Linear regression analysis of the L/H ratios for both methods was performed for the whole spectrum of the study in controls, fibrotics and cirrhotics. Ultrasonography prior to scintigraphy verified portal vein patency.Results: LRBC was valuable in differentiating fibrosis from controls (L/H=0.43±0.04 versus L/H=0.58±0.08, respectively; P<0.001), whereas CHS did not perform well in this context (L/H=9.2±2.66 versus L/H=12.0±2.97, respectively; P=0.13). The L/H ratios with both methods in cirrhosis were significantly lower than those of controls (LRBC: L/H=0.32±0.09 in cirrhosis versus L/H=0.58±0.08 in controls; P<0.000001; CHS: L/H=5.06±3.6 versus L/H=11.9±3.1, respectively; P<0.0001). The LRBC and CHS L/H ratios between the different cirrhotic stages and the controls resulted in the following correlations: LRBC L/H: 0.38±0.06 in stage A (P<0.0002), 0.3±0.037 in stage B (P<0.00001), and 0.16±0.02 in stage C (P=0.00007), versus 0.58±0.08 in controls, and CHS L/H10min: 8.25±1.78 in stage A (P=0.006), 2.58±2.04 in stage B (P=0.002), and 1.3±0.02 in stage C (P=0.029) versus 11.9±3.1 in controls. Statistically significant difference was demonstrated by both modalities between fibrosis and cirrhosis (LRBC: L/H=0.44±0.06 in fibrosis versus L/H=0.32±0.09 in cirrhosis, P= 0.003, and CHS: L/H=9.73±2.8 versus L/H=5.06±3.6, respectively; P=0.024). Linear regression analysis regarding L/H ratios revealed significant coefficients of (inverse) correlation for the disease severity by both LRBC and CHS, in the whole population studied (r= -0.835, P< 0.001 and r=-0.814, P<0.001, respectively).Conclusions: Scintigraphic evaluation of hepatic blood flow can discriminate liver fibrosis from cirrhosis. The LRBC study provides useful information in the follow-up of early liver dysfunction, which is not available from CHS studies.

P661 Cholecistigraphic detection of biliary leaks. M. P. Garcia Alonso, M. A. Balsa Breton, F. J. Penin Gonzalez, C. Peyillera; Hospital Universitario de Getafe, Madrid, Spain. The early diagnosis of bile leak (BL) in post surgical or posttraumatic patients can significantly reduce mortality and morbidity. The possibility of biliary tract disruption should be considered in any patient who has unexplained abdominal pain after bile ducts surgery. Symptoms, laboratory testing and physical examination are poor predictors for the presence of BL. Ultrasound and CT imaging are capable of detecting accumulation of fluid with high sensitivity but they cannot determine the type of fluid present. The hepatobiliary scintigraphy (HBS) can confirm that a fluid collection is derived from the biliary system, identify active BL and estimate the rate of leakage. OBJECTIVE: To review our diagnostic experience with BL in postoperative patients. MATARIAL AND METHOD: We have retrospectively studied 20 patients (10 females and 10 males) between 19 and 84 years old who underwent HBS for a possible postoperative BL; 18 after cholecystectomy and 2 after liver surgery. We used Mebrofenin-99mTc and the presence of BL was classified as mild or severe.Results: In 3 patients the HBS was negative and another diagnostic tests were used to search for other causes of the symptoms. In 8 patients the HBS found mild BL; in all of them it was resolved without aggressive therapy. In 9 patients the HBS found severe BL and everyone, except 2 cases who were resolved spontaneously, needed aggressive therapy to resolve it.Conclusions: HBS is a non-invasive method with a high sensitivity and a very high specificity for demonstration or exclusion of a BL so, in cases of clinical suspicion it should be used as primary investigational tool. Negative HBS should lead to a search for other causes of the patient’s symptoms.

P662 99m

Clinical Usefulness of simplified methods of Tc-HEPIDA plasma (ClPl) and specific hepatic (ClHp) clearance determination for assessment of functional condition of the liver M. J. Surma, K. Jencz, I. Frieske, J. Kusmierek; Medical University of Lodz, Lodz, Poland. A simplified method for determination of 99mTc-HEPIDA clearances (plasma, specific hepatic) is based on one measurement of radiopharmaceuticals concentration in plasma in the interval from 68 to 83 min post injection of a known activity of the compound, and upon determination of the activity in urine, voided ab 5 min post blood sampling. The aim of present investigation was to see whether simplified procedures offer usefulness from the clinical standpoint. Study group: Archived data from 134 individuals (48 healthy volunteers and 84 patients with chronic liver parenchyma diseases) in whom both clearances were determined by means of standard multisample methods were used.Methods: Plasma and hepatic clearances were determined by a simplified method, utilizing alternative 3 blood ssampling times at: 60, 75 and 90 min p.i. For clearance calculation the stored archived data were utilized: of administered activity, of plasma concentration of the radiopharmaceutical sampled at three above mentioned times, and of voided activity at times shorter than 100 min post injection. As a reference information on clinical condition of the liver function an assessment was used based upon several commonly applied biochemical indicators (AsT, AlT, GGTP, bilirubin, proteinogram, and protrombin indicator). Each indicator, depending on its value, was ranked with the point number from 0 to 5, and then the rangs of each individual were added giving the point sum - SP. The results of simplified determinations of clearances were correlated with archived values of clearances and with SP.Results: The correlation of results for clearances obtained by two methods (standard, simplified) were tightly correlated (r>0.9). For the simplified procedures of ClPl and ClHp determinations there was a negative correlation with SP: |r|•0.65. The values of r are very close to those obtained previously by using the standard multisample determinations. The Ȥ2 values for ClPl and ClHp vs SP .50 and .60, respectively, speak also for existence of a significant relationships between the clearance values and liver parenchyma condition. These Ȥ2 values are very close to those seen previously when multiplesample methods were used. Similarly also, the analysed relationships are more tight for ClHp than for ClPl.Conclusions: Both clearances ClPl and ClHp, determined by a simplified method, reflect the functional condition of liver. Specific hepatic clearance reflects the liver condition more adequately than the plasma clearance of 99mTc-HEPIDA. A simplified method for hepatic clearance may be used for diagnostics of the liver parenchyma performance.

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P663 Assessment of accuracy and precision of 99mTc-HEPIDA clearances determined by means of simplified methods M. J. Surma; Medical University of Lodz, Lodz, Poland. The aim of the present study was assessment of accuracy and precision of the own simplified methods in question.Methods: It has been assumed that archived results of ClPl and ClHp determined by means of multisample methods, could be legitimately used as a reference standard. A model of 99mTc-HEPIDA behaviour, based on bi-exponential curves and one blood sample taken at 68 or 75 or 83 min, was created. Rectangular distributed random errors were introduced into sampling time, and normally distributed into activity measurements. For each setting, the random errors were successively introduced 5000 times and the average values of ClPl and ClHp, as well as their coeffcient of variation (CV) calculated. Variable error in ClPl and ClHp was induced by errors in sampling time and activity counting. Accuracy of the simplified methods was assessed comparing mean values of simulated clearance computations with the reference. Values of CV were used as precision.Results: There were tight correlations between reference clearance values and the mean values of determinations by means of simplified procedures (r > 0.93). The correlations are practically insensitive to the uncertainty of pipetting. The lines of regression differ slightly from lines of identity, and this gives an indication there is a systematic error involved; it amounts to +4 ml/min at ClPl = 60 ml/min and to - 7ml/min for ClPl of 370 ml/min. For ClHp the bias was found of +6 ml/min for clearance value of 16 ml/min and 13 ml/min at ClHp > 300 ml/min. At uncertainty of pipetting of 2% the precision of 6-7% was found for ClPl of 300 ml/min. For ClPl of 200 and 150 ml/min the corresp. precisions were 7-8% and 10%. For ClHp of 200, 150 and 100 ml/min the corresponding precisions were 10, 12 and 17%. These precisions are by . 5 per cent worse than those for corresponding ranges obtained from determinations by means of multisample procedures.Conclusions: Accuracy of simplified methods for determination of satisfactory.

99m

Tc-HEPIDA clearances is

Precision of ClHp is somewhat less satisfactory than that of ClPl, but offers beteer representation of liver function than the latter. It varies in the range from 100 to 200 ml/min from 17 to 10%. Precision of ClPl depends predominantly on its value and ranges from 5% at high values to 20% at low values of the clearance.

P664 Estimation of Tc-99m GSA regional liver clearance from whole liver clearance and static liver SPECT: comparison with voxel by voxel analysis of dynamic SPECT N. Shuke, A. Okizaki, T. Sasaki, J. Sato, H. Sugimori, T. Aburano; Asahikawa Medical College, Asahikawa, Japan. OBJECTIVE: Functional mapping of Tc-99m GSA liver clearance (GSA CL) is useful for quantitative evaluation of regional liver function. It has been generated by analyzing regional liver kinetics with dynamic SPECT on a voxel by voxel basis. As a simple alternative method to the voxel by voxel analysis, a simple method that utilizes whole liver GSA CL and static liver SPECT was proposed and compared with the method based on the voxel by voxel dynamic SPECT analysis.METHOD: A total of 33 patients with chronic liver disease (Age: 66±10, M/F: 24/9) were studied with Tc-99m GSA dynamic SPECT (20 rotations / 20 min). Functional maps of regional liver GSA CL were generated by 2 methods. As a usual method, Patlak plot was adopted to calculate GSA CL on a voxel by voxel basis, using voxel liver time-activity curves (TACs) and cardiac blood pool TAC as an input function. As an alternative method, whole liver GSA CL was calculated from whole liver TAC and cardiac blood pool TAC by using Patlak plot. Then regional GSA CL was determined by allotting whole liver GSA CL to each voxel in proportional to voxel count of a static equivalent SPECT image generated by merging dynamic SPECT data (16-20 min). To compare the methods, right lobar regional GSA CL obtained from the voxel by voxel dynamic SPECT analysis was compared with that from the proportional allotment of whole liver GSA CL to the static SPECT. RESULTS: By visual inspection, functional GSA CL maps by the proportional allotment of whole liver GSA CL to the static SPECT showed better image quality with less statistical noise, compared to those by the voxel by voxel dynamic SPECT analysis. Right lobar liver GSA CL (ml/min) ranged from 10 to 667 (159±132) by the voxel by voxel dynamic SPECT analysis, and from 5 to 729 (154±146) by the proportional allotment of whole liver GSA CL to the static SPECT, showing good linear correlation (X/Y: static/dynamic, Y=0.89 X + 22, R2=0.959, SEE =27, P < 0.00001). CONCLUSION: Proposed method that utilized whole liver GSA CL and static SPECT could be used as a simple alternative method to the usual method based on the voxel by voxel analysis of dynamic SPECT for the evaluation of regional liver function.

P665 99m

The clinical value of tc-RBC scintigraphy in diagnosis of obscure gastrointestinal bleeding (OGIB) S. L. Chen1, J. Chen2, Q. Zhang1, X. Z. Sun2, X. F. Chen1, Y. S. Gu1, W. G. 1 Liu1, S. G. Chen1; Zhongshan Hospital,Institute of Nuclear Medicine,Fudan University, Shanghai, China, 2Zhongshan Hospital,Fudan University, Shanghai, China. Obscure bleeding is defined as bleeding of unknown origin that persists or recurs after negative initial or primary endoscopic evaluation (colonoscopy or upper endoscopy). Most of the gastrointestional bleeds the lesion can be identified by Routine studies. For gastrointestinal bleeding without obvious source of the bleeding, Small bowel lesion should be considered. Follow-up testing is required, e.g. Nuclear medicine scans, barium studies of the small bowel, small intestine endoscopy, Capsule Endoscopy(CE), Digital Subtraction Angiography(DSA),or Intraoperative endoscopy, to identify the source of gastrointestinal bleeding. The objective of this study was to evaluate the clinical value of 99mTechnetium labelled red cell (99mTc-RBC) scintigraphy in diagnosis of Obscure Gastrointestinal Bleeding (OGIB).Methods: Thirteen

P52 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Gastroenterology 2 P666 Role of scintigraphy in evaluation of salivary gland function B. R. Mittal, A. Bhattacharya, H. V. Sunil, D. Behera, M. Parmar, B. Singh; Pgimer, Chandigarh, India. Objective: Scintigraphic methods continue to play a prominent role in the study of functional disorders of salivary gland. In this study a qualitative method providing two functional parameters for assessment of salivary gland function by scintillation camera imaging was tested.Methods: Fifty consecutive patients referred for salivary scintigraphy were studied. Dynamic imaging of the head was performed in anterior position under a scintillation camera following intravenous administration of 4 mci of 99mTc pertechnetate at 15 seconds per frame for 20 min. At 10 min after the injection 5 ml of lemon juice was given orally. Analysis of the dynamic study included time activity curves of four salivary glands (right and left parotid, right and left submandibular glands). Two qualitative parameters of the salivary gland, uptake and drainage, were defined. Results: The study group consisted of 24 patients with a referral diagnosis of Sjogren’s syndrome and 16 patients with recurrent parotitis. Ten other patients with non-specific parotid swelling were excluded from the analysis. Of the 24 patients with Sjogren’s syndrome 13 had impaired uptake function in the left parotid, 11 in the right parotid, 11 in the left submandibular, and 12 in the right submandibular glands. Bilateral impairment of all four glands was seen in 5 patients while 3 patients showed involvement of only bilateral parotids. Drainage function was impaired in 9 patients in the left parotid, 4 in the right parotid, 6 in the left submandibular, and 6 in the right submandibular glands. Of 16 patients with recurrent parotitis, 12 had impaired uptake function in the left parotid, 7 in the right parotid, 4 in the left submandibular, and 5 in the right submandibular glands. Bilateral impairment of parotid gland function was seen in 6 patients, and of all four glands in 3 patients. Drainage was impaired in 9 patients in the left parotid, 4 in the right parotid, 3 in the left submandibular, and 4 in the right submandibular glands.Conclusions: Scintigraphy is a simple, non-invasive technique to evaluate uptake and drainage function of salivary glands. Impairment of individual parotid and submandibular gland function is almost equal in patients with Sjogren’s syndrome, while all four glands were involved in only 20% patients. Patients with recurrent parotitis showed impaired function more in the right parotid gland and equal incidence in the submandibular glands. Drainage was more impaired in the left parotid gland in both groups.

P667 SPECT for gastric volume assessment: performance of observer defined regions of interest J. L. Madsen1, S. Fuglsang1, J. Graff2; 1Hvidovre Hospital, Copenhagen, Denmark, 2Rigshospitalet, Copenhagen, Denmark. Aim: Three-dimensional single-photon emission computed tomography (SPECT) imaging allows non-invasive measurement of gastric volume. In previous studies, the processing of the SPECT data involved global threshold algorithms that do not take into account the non-uniform distribution of radioactivity in the gastric wall. This study aimed to develop a simple and robust scintigraphic method based on observer defined regions of interest to measure gastric volume.Materials and Methods: Twelve healthy volunteers participated in the study. At baseline, determination of gastric volume was based on SPECT imaging after intravenous injection of about 200 MBq 99mTc-pertechnetate. After ingestion of about 2 MBq 111In-diethylenetriaminepentaacetic acid in a 600-ml liquid meal, dual-isotope technique with SPECT and planar imaging assessed gastric volume and gastric emptying. Repeated calculations derived from SPECT data from three of the volunteers were used to evaluate the reproducibility of the volume measurementsResults: The median volume of the stomach was 86 ml (range 62-130 ml) at baseline, 642 ml (536-748 ml) immediately after the meal, and 370 ml (221-481 ml) 1 h after the meal. The coefficient of variation for the calculations was 9%, 2%, and 4%, respectively. The median increase in gastric volume was 562 ml (501-628 ml) immediately after the meal and 294 ml (159-370 ml) after 1 h. Gastric retention of the meal was 68% (50-73%) after 0.5 h and 51% (39-57%) after 1 h.Conclusions: This method seems to provide reliable assessments of gastric volume. In healthy subjects, the gastric accommodation response after a 600-ml liquid meal does not seem to cause an increase in gastric volume that differs from the volume of the meal.

P668 Active inflammatory bowel disease: 99m comparison between tc- hmpao- wbc and scintigraphy

head-to-head tc (v) dmsa

99m

M. Stathaki, I. Koutroubakis, S. Koukouraki, K. Karmiris, E. Kouroumalis, N. Karkavitsas; University Hospital, Iraklion, Crete, Greece, Iraklion, Greece. Purpose: the purpose of this study was to evaluate and compare the role of pentavalent (V) technetium 99m (99m Tc) DMSA and 99mTc-HMPAO-WBC scintigraphy in the detection, localization and the assessment of disease activity in patients with active inflammatory bowel disease (IBD). Material-Method: 99mTc (V) DMSA scintigraphy was performed in 11 patients with clinically and endoscopically confirmed active IBD and true positive 99mTc-HMPAO- WBC scintigraphy. The interval between the scintigraphic studies ranged from 3-4 days. Endoscopy was subsequently performed to confirm active IBD. 10mCi of 99mTc-HMPAO-WBC and 15mCi of 99mTc (V) DMSA was intravenously injected in all patients included in the study. A gammacamera (Millenium GE Medical System) equipped with a low energy all purpose collimator was used. With the patient in the supine position, planar views of the abdomen were obtained 2 hours after 99mTc-HMPAO-WBC and 4 hours after 99mTc (V) DMSA injection. Before scanning patients were asked to void their bladders to avoid false results. The bowel was divided in five segments: small bowel, ascending colon, transverse colon, descending colon and rectosigmoid. Images were considered positive when an area of increased uptake was observed in any of the five segments. To assess severity of IBD, semiquantitative measurements were included with reference to the uptake in the iliac crest and was graded as: 0: no uptake in the region of interest, 1: faint uptake less than the iliac crest bone marrow, 2: moderate uptake similar to that of the iliac crest, 3: severe uptake greater than the iliac crest bone marrow. Scintigraphic results were compared with endoscopic, radiologic and clinical data.Results: In five out of eleven (5/11) patients with increased uptake on the 99m Tc-HMPAO-WBC scans, a severe uptake of 99m Tc (V) DMSA in the bowel was also observed in the sites correspond with the inflammatory sites seen on 99m Tc-HMPAO-WBC scintigraphy and endoscopy. In four out of eleven(4/11) patients, an increased uptake of 99m Tc (V) DMSA was refered only in the sites of maximal uptake on 99m TcHMPAO-WBC images and in two out of eleven (2/11)cases no increased uptake of 99m Tc (V) DMSA was seen (false negative results).Conclusions: 99m Tc (V) DMSA could provide a useful noninvasive alternative inflammatory agent for the detection, localization and the assessment of disease activity in patients with active IBD. These are the preliminary results of an ongoing study.

P669 Detection of abdominal and gastrointestinal infections using 99m Tc labelled monoclonal antibodies (BW 250/183) V. Obradoviü1, V. Artiko1, M. Petroviü2, N. Petroviü1, B. Davidoviü1, M. Vlajkoviü3; 1Institute for Nuclear Medicine, Clinical Center of Serbia, Beograd, Serbia and Montenegro, 2Institute for Digestive Diseases, Clinical Center of Serbia, Beograd, Serbia and Montenegro, 3Center for Nuclear Medicine, Clinical Center Niš, Niš, Serbia and Montenegro. Purpose: The aim of the study was detection of abdominal and gastrointestinal infections by 99m Tc- antigranulocyte antibodies. Methods and Materials: Total of 20 patients with clinical suspicion on abdominal or gastrointestinal infections was investigated. An hour, 4h, and when necessary, 24h after slow i.v. injection of 370 MBq 99mTc labeled monoclonal antibodies BW 250/183 in the cubital vein, whole body scintigrams were obtained in anterior and posterior positions. The study was supplemented, when needed, with additional scintigrams of the selected regions (500 000 imp/view) and tomography (360º/6°). Additional data were provided using clinical findings, ultrasonography, computer tomography, magnetic resonance imaging, laboratory analyses, as well as surgical or microbiological confirmation of infection.Results: There were 12 true positive (TP) findings (2 subhepatic abscesses after surgery, one perianal fistula, 5 abdominal and one pelvic abscess, 3 Crohn's diseases), 4 true negative (TN) (2 ileal tumors, one duodenal tumor, one gastric carcinoma), 3 false negative (FN) (2 subphrenic abscesses and enterocolic fistula). In one patient (also TP) pulmonary abscess was confirmed. The smallest lesion found was 20x20 mm. SPECT increased the number of TP findings from 8 to 13. Seven of 13 infectious of inflammatory lesions could be detected in the early scan. Sensitivity was 81%, specificity 100%, positive predictive value 100%, negative predictive value 57% and accuracy 85%. In 5 patients infection was caused by Escherichia coli, 2 with Proteus mirabilis, 2 with Pseudomonas aeruginosa and 1 with Klebsiella, while in 3 only the surgical confirmation of infection existed. In two FN patients, infection was caused by Proteus mirabilis, while in the third one E.coli was found.Conclusions: According to our results, scintigraphy with 99mTcantigranulocyte antibodies is an useful method for detection and assessment of exact localization abdominal infections, which is very important for the prompt and appropriate therapy choice.

P670 The relationship between blood groups and helicobacter pylori infection in the patients with idiopathic thrombocytopenia V. Artiko1, N. Suvajdžiü2, B. Stankoviü3, M. Vlajkoviü4, V. Obradoviü1; 1 Institute for Nuclear Medicine, Clinical Center of Serbia, Belgrade, Serbia and Montenegro, 2Institute for Hematology, Clinical Center of Serbia, Belgrade, Serbia and Montenegro, 3Center for Rehabilitation of Hematological Patients, Ivanjica,, Ivanjica, Serbia and Montenegro, 4Center for Nuclear Medicine, Clinical Center of Niš, Niš, Belgrade, Serbia and Montenegro. Aim Blood groups A and O have been reported to be related to H. pylori infection, while blood group A have been reported to be related to chronic idiopathic thrombocytopenia (ITPchr). Concerning the controversies in the reports, the aim of our study was to assess the relationship between H. pylori infection in the patients with chronic idiopathic thrombocytopenia (ITPchr)

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Poster Presentation

patients (6 men, 7 women, mean age 54.30+-16.06 y, age range 21-81y) with Obscure Gastrointestinal Bleeding (OGIB) were included in this study. The results of 99mTc-RBC scintigraphy performed in 13 patients presenting with gastrointestinal tract bleeding were compared with the results of Brium Meal, fiber gastroscope, fiber colonscope, DSA, CE, Computer Tomography (CT), Magnetic Resonance Imaging (MRI) and small intestine endoscopy. And compared with the finding of operation.Results: In all of the thirteen patients, the gastroscopy, Brium Meal and colonscopy were performed without obvious source of the bleeding, except 1 case was indentifed by gastroscopic biopsy. 99mTc-RBC scintigraphy was performed in these 13 cases, and the results of 12 cases were positive and 1 case was negative. Further testing, such as DSA, CE, CT and small intestine endoscopy was performed in these 99mTc-RBC scintigraphy positive patients. 66.7% bleeding region were focused by DSA. CT scan revealed that the occupier lesions were the cause of bleeding in 3 patients. The results of 99mTc-RBC scintigraphy were confirmed by surgery, and the lesions of bleeding were matched with the 99mTc-RBC scintigraphy displayed.Conclusions: Fitable examination should be chosen depended on the individual differences and condition in diagnosis of OGIB. Gastrointestinal tumor must be taken into account for the old, repeated gastrointestinal tract bleeding and ineffectual routine therapy. Barium studies of the small bowel are widely available but have limited diagnostic utility. Small bowel endoscopy is difficult to perform but has a higher diagnostic yield. Capsule endoscopy is a newer technique that allows noninvasive small bowel imaging. 99mTc-RBC scintigraphy is a noninvasive, secure, simple, and useful examination, which can be used in diagnosis of OGIB.

and their blood groups (ABO, Rheusus-Rh).Materials and Methods: 54 adults with ITP chr (12 male, 42 female; median disease duration 6 years; median age 51 years; mean platelet count: 70 x 109/L; 7 refractory; median follow-up 10 months) entered the prospective study between February 2002 - June 2005. All patients had a diagnosis of ITP chr according to the American Society of Hematology guidelines and presented with a platelet count of less then 120 x 109/L for 6 months or more without megacariocytic hypoplasia in the bone marrow. Other causes of thrombocytopenia, such as drugs, pseudothrombocytopenia, hepatitis C virus, human immunodeficiency virus, malignancy and autoimmune disorders were excluded. H. pylori infection status was assessed by C14 urea breath test.Results: H. pylori infection has been documented in 39/54 (72.2%) patients which is significantely higher than in general population in our country (55%) p <0,05. H. pylori positivity was 64,7%, 81.8%, 80,0% and 66,7% in blood proups O, A, B and AB respectively (X²=1.751 DF=3 P=0.626). H. pylori positivity was 71,1% and 77,8% in Rh(+) and Rh(-) blood subgroups, respectively (X²=0.166 DF=1 P=0.684). The rate of H. pylori infection was not statistically different between subjects of different ABO or Rh blood groups (P>0.05).Conclusions: According to our results, in ITP chr patients, there is no association between H. pylori infection and ABO/Rheusus blood groups.

P671 Does intravenous nitroglycerin affect gastric and small intestinal motor function in healthy humans? J. L. Madsen1, S. Fuglsang1, J. Graff2; 1Department of Clinical Physiology and Nuclear Medicine, Hvidovre Hospital, Copenhagen, Denmark, 2 Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Copenhagen, Denmark.

group of patients with clinical suspicion of PLE.Materials and Methods: 11 patients who were applied Tc-99m Dextran scintigraphy between the years 2003-2005 with clinical suspicion of PLE were included in the study. After slow i.v. injection of 5-10 mCi Tc-99m Dextran, serial images of 1000 kcounts were obtained on 10th, 30th minutes, 1st, 2nd, 4th and 24th hours zooming pelvis and abdomen. Accumulation of Tc-99m Dextran outside of the physiological uptake sites was accepted positive for PLE.Results: All patients (6F, 5M; age range 1-42) were applied Tc-99m Dextran scintigraphy. 13 scintigraphic studies were performed to these 11 patients. Eight of 13 studies (61.5%) were found to be positive. Increased Tc-99m Dextran accumulation was noted in the first 4 hours images. Delayed 24th hour images added no new findings. One of the patients who, was a five-year-old boy with clinical suspicion of intestinal lymphangiectasia had an accumulation site on mid-abdominal region and underwent surgery. Postoperative control Tc99m Dextran scintigraphy showed persisting accumulation due to PLE. Discussion: Tc-99m Dextran scintigraphy is an easy, cheap and non-invasive imaging technique which is useful for diagnosing PLE, deciding for operation and evaluating the results of treatment.

P674 Evaluation of normal gallbladder ejection fraction after a standard fatty meal ingestion using Tc99m-sestamibi V. Dabbagh Kakhki, S. Zakavi, Y. Davoudi, A. Yousefi, H. Bakhtiari; Mashhad University of Medical Sciences, Mashhad, Iran (Islamic Republic of).

Aim: After intravenous infusion, nitroglycerin (NTG) is converted into nitric oxide (NO). NO is an important non-adrenergic, non-cholinergic neurotransmitter in the gastrointestinal tract, inducing smooth muscle cell relaxation. Therefore, intravenous infusion of NTG may be useful in studies on the significance of NO mechanisms in the control of human gastrointestinal motor activity. Little is known about the effect of NO-donors on gastric motor function and no data exist on the possible effect of a NO-donor on the propulsive activity of the entire small intestine. This study examined the effect of intravenous infusion of NTG on gastric and small intestinal motor function after a meal in healthy humans.Materials and Methods: Nine healthy volunteers (23-31 years) participated in a placebo-controlled, double-blind, cross-over study. Each volunteer was examined during intravenous infusion of NTG 1 µg/kg x min or saline. Repeated sequences of static and dynamic gamma camera imaging were used to measure gastric emptying, frequency of antral contractions, and small intestinal transit after a 1,600-kJ mixed liquid and solid meal. Furthermore, duodenal motility was assessed by manometry.Results: Infusion of NTG caused a small, but significant decrease in systolic blood pressure, whereas heart rate was not changed. However, NTG did not change gastric mean emptying time or small intestinal mean transit time of 111In-labelled liquid marker or 99mTc-labelled solid marker. Neither was the postprandial frequency of antral contractions affected by NTG. NTG did not influence the mean frequency of duodenal contractions, the mean amplitude of duodenal contractions or the duodenal motility index after the meal. Six subjects reported mild or moderate headache and one subject had a sensation of heat during the infusion of NTG.Conclusions: Intravenous infusion of NTG 1 µg/kg x min does not seem to induce major changes in gastric or small intestinal motor function after a 1,600-kJ meal in healthy volunteers.

Sincalide in conjunction with cholescintigraphy is necessary for diagnosis of chronic acalculous cholecystitis. However sincalide is not widely available and alternatively numerous different fatty meals have been used to evaluate gallbladder ejection fraction (GBEF) by different methodologies to evaluate the adequacy of gallbladder contraction. Aim: This study is designed to develop a standard fatty meal using a commercially available formula and to determine normal GBEF values using this supplement. Patients and methods: We studied 25 patients (12 men and 13 women) aged 33-87 years (mean: 51.5±11.5 years) with body mass index(BMI) from 16.9 to 38.7 (mean: 26.8± 5.4) who were referred for Tc99m-sestamibi myocardial perfusion SPECT. They did not have any symptoms with abdomen, history of hepatobiliary and gallbladder disease, diabetes mellitus, abdominal surgery, or family history of hepatobiliary disease and were not taking any medication known to affect biliary system. Other medications are discontinued at least 2 days before the study. All were prescreened with a GB and liver ultrasonography to exclude any abnormality. After 6 hours fasting, 20 mCi of Tc99m-sestamibi was injected intravenously at rest and 90 minutes later the subjects ingested the 120 CC of formula(Humana :containing 10 g fat ).In a preliminary study on other 15 patients, maximal GB concentration of Tc99m-sestamibi was 90 minutes after tracer injection. After background and decay correction, GBEF was calculated at 30 and 60 minutes after fatty meal ingestion using anterior images. Results: Mean GBEF at 30-minute and 60-minute was 66%±22.3% (8.97%-99.9%) and 82.2%±12.4% (40.4%100%) respectively. GBEF at 30-minute and 60-minute did not differ significantly between men and women (P=0.7 & P= 0.4). There was no statistical significant correlation between BMI and GBEF( at 30-minute: P=0.20, r=0.26, at 60-minute: P=0.18, r=0.27). There was a probability of ” 4% for normal subjects to have a GBEF” 8.97% at 30-minute and GBEF ”40.47 at 60-minute. Conclusion: A standard fatty meal and normal GBEF( at 60-minute: 66%±22.3%) were established for fatty meal cholescintigraphy.

P672

P675

Esophagus transit scintigraphy with three different type of radioactive bolus materials (liquid, semisolid and solid) in normal subjects

Scintigraphic changes in the salivary glands in patients with advanced stage of metabolic syndrome

S. Türkölmez, F. Aydogan, D. Çayir, E. Özdemir, G. Koca, K. Demirel, M. Korkmaz; Ankara Training and Research Hospital, Ankara, Turkey. Aim: The radionuclide esophageal transit study (ETS) is a simple, safe, and highly sensitive method for detecting the dysmotility or dysfunction of the esophagus. Esophageal scintigraphy can be performed by using different type of radioactive bolus material (liquid, semisolid or solid). However, there are various pitfalls in technique and interpretation. Normal ranges of the esophageal transit time (ETT) have not been generally agreed upon. To our knowledge there are no published reports of a comparison of these 3 techniques. In the present study, the aim was to evaluate the results of ETS using liquid, semisolid or solid radioactive bolus material in normal subjects.Materials and Methods: We studied 91 healthy volunteers (30 female, 61 male; mean age: 33.58±10.36 years, range: 16-65 years). The ETS was performed to all subjects using liquid (water), semisolid (apple puree) and solid (egg) radioactive bolus materials. The condensed image was created and region of interests were generated for the upper, the middle and the lower 1/3 portion and whole esophagus using the condensed image. Time-activity curves were created. The transit times for the upper, the middle and the lower 1/3 portion and whole esophagus were calculated.Results: ETT values using liquid bolus for upper, middle and lower one-third of the esophagus and the whole esophagus were 2.60±0.85, 3.95±1.22, 5.90±1.38 and 6.57±1.53 sec, respectively. ETT values using semisolid radioactive material for upper, middle and lower onethird of the esophagus and the whole esophagus were 3.94±1.53, 6.51±2.11, 8.26±2.14 and 10.35±2.27 sec, respectively. ETT values using solid radioactive material for upper, middle and lower one-third of the esophagus and the whole esophagus were 7.23±2.77, 10.54±3.08, 13.65±4.94 and 15.86±3.75 sec, respectively. Conclusions: ETT values in normal subjects using liquid, semisolid and solid radioactive material were 6.57±1.53, 10.35±2.27 ve 15.86±3.75 sec, respectively. The results of the esophagus transit scintigraphy may be influenced by the type of ingested material.

P673 Imaging with Tc-99m dextran in protein loosing enteropathy A. Akgun, A. Oral, M. Taner, N. Mutlukoca; Ege University Medical Faculty Department of Nuclear Medicine, øzmir, Turkey. Aim: Protein loosing enteropathy (PLE) is a rare syndrome characterized by excessive loss of protein via gastrointestinal mucosa. PLE can be related to many intestinal or extra-intestinal diseases. In this study we searched for the clinical value of Tc-99m Dextran scintigraphy in a

S360

A. Klisarova1, B. Chaushev2, P. H. Bochev1, M. Hristova1; University, Varna, Bulgaria, 2St.Marina Hospital, Varna, Bulgaria.

1

Medical

It is known that some diseases of the central and vegetative nervous system, infectious and systemic diseases are manifested clinically by functional or morphological disorders of the salivary glands. A new pathway of the neuro-immuno-endocrine interaction has recently been established, namely cervical sympathetic truncus axis - submandibular salivary gland. The function of the salivary glands is under the indirect control of the hypothalamus. Changes in hypothalamus and pituitary gland result in atrophy of the submandibular glands. Beside the endocrine system the regulation of the salivary glands also involves the autonomous nervous system. Based on the above mentioned correlations and earlier hypotheses that salivary glands are affected in metabolic syndrome we aimed to detect the changes in salivary glands in a group of patients with metabolic syndrome. Subject to study were 20 patients in advanced stage of metabolic syndrome which were diagnosed according to the criteria adopted by the Adult Treatment Panel III of the US educational program on cholesterol. Scintigraphy of the salivary glands with 99mTcO4- was performed, using dynamic acquisition protocol and stimulation with citric acid. In 8 patients we found normal fixation of the radioactive nuclide and preserved function. In two of them hypertrophy of the salivary glands was detected. In the remaining 12 patients a low radioactive nuclide fixation was detected together with disordered function of the salivary glands. In 4 patients we detected hypertrophy of some or all the salivary glands. In 8 patients atrophy of glandular parenchyma was revealed. In conclusion we found the dynamic salivary gland scintigraphy a useful tool in the detection of early changes in salivary glands in patients with metabolic syndrome as well as staging of the severity of disturbance of salivary gland parenchyma.

P53 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Metabolic Studies P676 99m

Correlation of hypercalcaemiae with Tc MDP whole body scan in the diagnosis of bone metastases: the value of

R. Miftari1, X. Bicaj2, L. Abdullahu1, I. Gërçari1, F. Fejza2, B. Xhafa1, H. 1 Paçarrizi3; nuclear medicine department, Prishtina, Serbia and Montenegro, 2Department of oncology and radiotherapy, Prishtina, Serbia and Montenegro, 3Department of Biochemistry, Prishtina, Serbia and Montenegro. Purpose: Several hitopathological studies have demonstrated that more than 3/4 of all bone cancers are metastase which have origins from primary cancer in an another organ.The aims of this study were to assess the performance of hypercalcaemiae and whole body 99mTc MDP scintigraphy in the early detection of bone metastases and to evaluate correlation between these two methods.Methods:One hundred-five patients with advanced primary cancer, verified in all cases by biopsy were enrolled in this perspective study. The primary tumors were 62 breast cancers, 19 prostate cancers, 5 pulmonary cancers, 2 plasmocitomas, 2 uterine cancers and 15 others.The serum calcium value and whole body scintigraphy were estimated at all 105 patients included in study group.We usually performed three phase bone scan after injection of 740 MBq 99m Tc MDP.Results: Eighty-five patients (80.95%) were found to have bone metastases. High level of serum calcium were found only in three patients (3.53%) with bone metastases.The sensitivity of serum elevated clacium in cases with bone matastases were 3.5%, the specificity were 100%, accuracy were 0.27, positive predictive value (PPV) were 1.o and negative predictive value (NPV) were 0.19. By scintigraphy were obtained eighty-four patients with suspect suspect bone metastases. Eighty-three (98.8%) of them were confirmed with bone metastases. Only one cas was registered as false positive (1.19%). Twenty-one patiens had scintigraphy without bone metastases. Twenty of them (95.23%) were confirmed without boned metastases. Only one case (4.76%) was registered as false negative scintigraphy. The sensitivity of scintigraphy were 98%, specificity 95%, accuracy0.98, predictive positive value 0.98 and negative predictive value were 0.95.Conclusions: Our preliminary results suggest that the elevated value of serum calcium is halpennyworth in early detection of bone metastases.Whole body bone scintigraphy demonstrate high sensitivity and specificity in early detection of bone metastases.

P677 Assessment of the relationship between bone scintigraphy and serum biochemical markers in hemodialysis patients S. Kurata1, M. Ishibashi1, H. Kaida1, H. Nishida2, Y. Hiromatsu3, S. Okuda2, N. Hayabuchi1; 1Kurume University School of Medicine, Division of Nuclear Medicine, PET Center and Department of Radiology, Kurume, Japan, 2 Department of Nephrology and Dialysis Unit, Kurume, Japan, 3Department of Endocrinology and Metabolism, Kurume, Japan. Aim: Renal osteodystrophy (ROD) is a metabolic bone disease and a common complication of maintenance dialysis treatment. Bone scintigraphy and serum biochemical markers have been recognized as sensitive methods for early detection and assessment of ROD. Based on serum biochemical markers, we have studied the diagnostic value of the bone-to-soft-tissue (B/ST) ratio using bone scintigraphy in non-invasive evaluations of the changes of bone metabolism in hemodialysis patients. Material and Methods: Technetium-99m-hydroxy-methylenediphosphonate semi-quantitative analysis of bone scintigraphy was performed on 41 patients (23 men, 18 women; age range, 22-77 y; mean age, 48.3 y) receiving maintenance dialysis treatment with three dialysis sessions per week. In all patients, bone scintigraphy was obtained approximately 3 h after intravenous injection. Whole-body images were recorded with a gamma camera. On whole-body posterior views, regions of interest (ROIs) were set over selected regions. The B/ST ratios were measured by drawing setting ROIs around the skull, the lumbar spine, the femoral neck and medial parts of the soft tissue areas of the thigh. The B/ST ratio at each region was calculated in all patients. Predialysis blood sampling was performed. Serum bone-specific alkaline phosphatase (BAP), serum deoxypyridinoline (DPD) and intact parathyroid hormone (intact PTH) were measured. The B/ST ratios were then compared with serum biochemical markers. Results: The B/ST ratio (mean ± SD) was 3.26 ± 1.53 in the skull, 9.43 ± 3.70 in the lumbar spine and 4.58 ± 2.08 in the femoral neck. The B/ST ratio for the skull correlated well with serum BAP (r = 0.711, p < 0.001), serum DPD (r = 0.764, p < 0.001) and intact PTH (r = 0.570, p < 0.001). The B/ST ratio for the lumbar spine did not correlated with serum BAP, serum DPD and intact PTH. The B/ST ratio for the femoral neck did not correlated with serum BAP, serum DPD and intact PTH. Conclusion: The B/ST ratio for the skull correlated closely with serum biochemical markers of bone turnover. Our data suggest that semiquantitative data analysis using bone scintigraphy is a sensitive and useful method for evaluating bone metabolism in hemodialysis patients. The B/ST ratio for the skull may reflect changes of bone metabolism in hemodialysis patients.

P678 99m

99m

Changes in Tc-methoxyisobutylisonitrile ( Tc-MIBI) uptake by skeletal muscles after aerobic training : potential for non-invasive metabolic imaging. D. Kyparos1, G. Arsos2, A. Kyparos1, S. Georga2, A. Petridou3, S. Sotiriadou3, V. Mougios3, C. Matziari3; 1Lab. of Physiology, Dept. of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece, 2Dept of Nuclear Medicine, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece, 31Laboratory of Physiology, Dept. of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece. Aim: Aerobic exercise induces adaptational increases in mitochondrial respiratory enzymes. 99m Tc-MIBI, a widely used radiopharmaceutical, is known to accumulate into cell mitochondria. The aim of the present study was to investigate changes in muscular uptake of 99mTc-MIBI after long-term endurance exercise, as a potential basis for metabolic muscle imaging. Animals and Methods: Twenty-six adult male Wistar rats were randomly allocated to a trained group (endurance exercise of 60 min, 25 m/min, 5 days/wk for 14 weeks on a motor-driven treadmill)

and an untrained group. On completion of the training program, 99mTc-MIBI (5.6 MBq/kg body weight) was administered i.v. to all animals. Two hours after injection, the soleus, medial gastrocnemius (MG), tibialis anterior (TA) and extensor digitorum longus (EDL) muscles were removed. Cytochrome c oxidase (CCO) activity was assessed spectrophotometrically after tissue homogenization and 99mTc-MIBI uptake was calculated after activity measurement in a well-type counter. Differences between trained and untrained rats were assessed for significance at p<0.05 level by the independent Student’s t test.Results: CCO, activity was significanly higher in the MG (11.2±0.7 vs 7.9±0.4 U/g), TA (13.4±1.1 vs 9.5±0.8 U/g) and EDL (13.2±1.3 vs 10.5±0.8 U/g) of the trained compared to sedentary rats. In both animal groups, CCO activity was highest in the slow-twitch soleus (22.4±1.3 U/g in trained, and 21.0±1.0 U/g in untrained). 99mTc-MIBI uptake was higher in the trained rats compared to the untrained rats in all muscles examined. Statistically significant differences were found in EDL (0.32±0.04 vs 0.21±0.03 %ID/g) and soleus (0.32±0.04 vs 0.24±0.03 %ID/g), while differences in MG and TA, although in favor of the trained group, were not significant. Similarly to CCO activity, 99mTc-MIBI uptake was highest in soleus (0.32±0.04 %ID/g in trained, 0.24±0.03 %ID/g in untrained) and lowest in MG (0.17±0.02 %ID/g in trained, 0.13±0.02 %ID/g in untrained).Conclusions: Slow oxidative muscles had higher levels of both CCO activity and 99mTc-MIBI uptake compared to fast glycolytic muscles. Moreover, training was associated with increase in both CCO activity and 99m Tc-MIBI uptake in almost all muscles examined. These findings suggest that 99mTc-MIBI can be a candidate tracer for the development of an imaging technique for the assessment of metabolic changes in skeletal muscle. Potential applications could involve both clinical and sports medicine issues.

P679 SeHCAT: a Retrospective Re-analysis and Audit L. Sanders, B. Kingsley, M. Masoomi; Royal Hospital Haslar, Gosport, United Kingdom. Aim SeHCAT studies were performed on twenty-three patients, 7 male (mean age 48.5yr) and 16 female (mean age 49.08yr), referred since 2002 and current processing procedures audited. Results obtained using different energy windows were compared, identifying potential error sources or pitfalls and identifying any recently published developments. Materials and methods Counts are acquired 3 hours and 7 days after administration of 370 KBq Se75 labelled Tauroselcholatic acid (SeHCAT). Anterior and posterior patient and background counts were acquired with an un-collimated gamma camera using a wide window (TOT)(103-574 KeV) of three summed 50% windows peaked at 137(LEW), 275(MEW) and 459(HEW) KeV. Percentage retention at 7-day (PR) is the decay corrected day 7 to day 1 counts ratio. Published papers quote normal PR ranging from >5% to >20% or biological T1/2 from 28 to 216 hours. The manufacturer quotes a biological T1/2 for 97-100% of absorbed SeHCAT of 2.6 days (PR 15.5%), the remainder clearing with a half-life of 62 days (PR 17.8%) i.e. normal >17.8%, equivocal 15.5 to 17.8% The manufacturer recommended energy window is 280KeV with 20% window (252-308). Earlier documentation recommended a wider window covering as much of the Se75 spectrum as was possible with the equipment available. Counting statistic errors were calculated on patient results for all sets of data. An energy plot for Se75 was performed and a test count performed with a 600MBq Tc99m source, equivalent to one bone scan patient, out and inside the room to investigate count contamination. Results Poor counting statistics in the HEW, particularly in cases of low retention, resulted in large errors. Accidental Tc99m contamination and tests results show increases in background in LEW, the effect on patient results was within statistical limits, the contamination being present during all acquisitions. No cut off between diagnostic groups was detected. The LEW contained 60% of counts. Reducing this window width to 20% reduced the count rate by over 50%. Change in diagnosis when separate windows were: Normal to equivocal; 1 Equivocal to normal; 1 Equivocal to abnormal; 1 Abnormal to normal; 2 Low counts in HEW preventing calculation; 2 There was poor concurrence between TOT, LEW, MEW and HEW results. Conclusion The HEW alone should not be used. Using three windows enables contamination identification, whether Tc99m or higher energy isotopes, e.g. F18, emphasising the need for acquisition specific background counts. Normal ranges and procedures need to be identified for this test.

P680 Glucose uptake transition from the fasted to the hyperglycemic hyperinsulinemic state in different body 18 organs by [ F]FDG-PET L. Guiducci1, V. Lionetti1, C. Simi1, S. Masi2, S. Pardini2, C. Porciello2, F. Magagnini2, P. Di Cecco2, E. Ferrannini3, P. A. Salvadori2, P. Iozzo2; 1 Institute of Clinical Physiology CNR Research Area; School of Advanced Studies S'Anna, Pisa, Italy, 2Institute of Clinical Physiology CNR Research Area, Pisa, Italy, 3University of Pisa, Pisa, Italy. Aim Daily metabolism is characterized by the alternation of fasting and fed conditions, requiring rapid organ adaptations, mainly translating in the up-regulation in glucose utilization (GU); metabolic inflexibility has been implicated in the pathogenesis of cardiovascular disease, diabetes and insulin resistant states. The aim of the study was to evaluate the simultaneous GU response of different organs to the fast-to-fed transition, as induced by an acute rise in circulating insulin and glucose values, mimicking post-prandial levels. Materials & methods Glucose doseresponse [18F]FDG-PET studies were conducted in pigs. Imaging of the heart, liver, adipose tissue, skeletal muscle and lungs was consecutively performed during euglycemic fasting conditions (EF), and during steady-state hyperglycemic hyperinsulinemia (HH) in the same study session. At the end of the experiment, biopsies were obtained in all soft tissues for the ex-vivo bio-distribution evaluation. Images were analyzed semiquantitatively (glycemia-adjusted standardized uptake value, SUV) and quantitatively (graphical analysis). Results A significant three-to-fourfold elevation in GU occurred in adipose tissue, skeletal muscle, liver and lung during HH vs EF (p<0.05). In EF, the myocardium was the predominant glucose consumer, while in HH GU was more prominent in the liver, supporting the role of this organ in postprandial glycogen storage. Ex-vivo bio-distribution measurements in HH additionally showed active [18F]FDG accumulation in the pancreas, and in epicardial and visceral fat depots. Conclusion Our protocol allowed document a changing partition in glucose utilization across different organs from the fast-to-hyperglycemic state, suggesting a pronounced post-prandial metabolic activity in the liver, pancreas and adipose tissue in accord with the role of these organs in modulating glucose storage.

S361

Poster Presentation

hypercalcaemiae as early diagnostic parameter of bone metastases

P681 Estimation of skin and adipose tissue metabolic burden by combining segmented CT and FDG- PET data G. Bural, D. Torigian, K. M. Alkhawaldeh, T. Cermik, M. Houseni, G. ElHaddad, A. Alavi; Hospital of the University of Pennsylvania, Philadelphia, PA, United States. Objectives: The skin is considered as the largest organ of the body. Adipose tissue is found underneath the skin and surrounds the internal organs. Our aim was to segment and then calculate the total metabolic burden of the skin and adipose tissue in the abdominal and pelvic regions by measuring their metabolic activities and multiplying it by their organ volume. Methods: We included ten subjects with no evidence of skin and or fat tissue diseases, (five men, five women; mean age 53±8 years). All subjects had CT scans of the abdomen and pelvis and FDG-PET scans. The time interval between the two scans was 1 -180 days with a mean of 71± 96 days. Skin and adipose tissue were segmented on the CT images using software analysis tools. The volumes of the abdominal and pelvic skin tissue and of the total adipose tissue were calculated from the CT images. The mean SUV for abdominal and pelvic skin and for subcutaneous adipose tissue were calculated from the PET data. We then multiplied the regional skin and adipose tissue volumes by the regional SUVs to calculate the regional metabolic burden for each patient. Results: The volume of abdominal skin ranged between 233-524 cm3 with a mean of 378±93 cm3. The volume of the pelvic skin ranged between 409-847 cm3 with a mean of 351±74 cm3. The range of mean skin SUV in the abdomen was 0.3-0.5; for pelvis it was 0.20.3. The total abdominal and pelvic skin metabolic burden values were 106-209 with a mean of 139±39 and 702-1138 with a mean of 891±16 respectively. The volume of abdominal adipose tissue ranged between 804- 11434 cm3 with a mean of 5611±3430 cm3. The volume of the pelvic adipose tissue ranged between 4098 -8517cm3 with a mean of 6634±1640cm3. The range of mean adipose tissue SUV in the abdomen was 0.3-0.5, for pelvis it was 0.2-0.4. The total abdominal and pelvic adipose tissue metabolic burden values were 2512-45238 with a mean of 24990± 4058 and 1229-2383 with a mean of 1899±516. Conclusions: Metabolic burden of the skin and adipose tissue are parameters that can be calculated and may be useful in assessing the quantitative changes in these organs due to diseases or following therapeutic interventions.

P682 Metabolic activity of normal skin as a function of age, gender and race G. Bural, K. M. Alkhawaldeh, M. Houseni, G. El-Haddad, T. Cermik, A. Alavi; Hospital of the University of Penssylvania, Philadelphia, PA, United States. Objectives: The aim of this study was to determine the range of normal skin FDG uptake in various body regions and the influence of age, gender and race on the uptake values. Methods: One hundred seventy-nine subjects without skin disease were included in the study. Age range was 3-84; 88 men, 91 women; 116 white and 63 black patients. The patients were arranged in multiple groups according to their ages, gender and race. The maximum skin SUV was measured by placing multiple ROIs for each patient on the posterior thorax region, anterior abdominal region, and gluteal region. The background activities for these regions were also noted. Partial volume correction was applied to generate the accurate skin FDG uptake as described in the literature.(Lubberink M et al. Journal of Nuclear Medicine 2002;43:1391-7). Analyses of the partial volume corrected SUVs were carried out for the effect of age, gender, race and various anatomical sites. Results: After partial volume correction, the skin SUVmax ranged between 1.35- 6.55. The maximum SUVs for three different body regions were higher in the black population than white population (p<0.05). The partial volume corrected SUVmax values for the black population in the posterior thorax, anterior abdominal region and gluteal region were 4.2±1, 3.4±1, 3.7±1 respectively. The values were 3.8±1, 2.8±1, 3.1±1.1 respectively for the white population. There were statistically significant differences for the three anatomical sites mentioned above in both races (p<0.05). In four different age groups, SUVmax values in all regions, for both races increased with age. The increase was statistically significant for the white population (p<0.05). There were no differences in the corrected SUVmax measurements in both races for gender. The mean SUV for the three regions noted above in white men were 3.3±1.1, in white women 3.2±1.0 (p>0.05). The average SUV for the three regions in black men were 3.6±1, in black women 3.7±1.1 (p>0.05). Conclusions: The SUVmax values after partial volume correction is higher in the black population than the white population. The reason for this finding needs further investigation and is likely related to the difference in metabolic activity of the histological composition of the skin. An increase in SUVmax values with aging occur in both races and again this should be investigated further in the future. This may be secondary to the cumulative effect of UV radiation with increasing age.

P54 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

ankles (80%), shoulders (84%), elbows (36%), wrists (52%), hands(48%) and feet (72%). Also Tie sternum sing (64%), patella sign (60%) were seen. Renal images were absent or faint vizualised in 19 paients (76%). To our findings endemic skeletal fluorosis can have a lot of scintigraphic findings even in subjects with normal other bone turnover markers.

P684 Combined MIBI and bone scan imaging in evaluation of Mono/Polyostotic Fibrous Dysplasia T. Öneú, G. E. Aktaú, H. Çiven, T. Y. Erdil, F. Dede, S. ønanır, H. T. Turo÷lu; Marmara University, Istanbul, Turkey. INTRODUCTION: Fibrous Dysplasia (FD) is a slowly progressive bone disorder in which normal bone is replaced by abnormal fibroosseus tissue. Conventional imaging methods such as plain radiography, computed tomography and magnetic resonance imaging have been used to diagnose FD. Although Tc99mMDP, Ga67 Citrate, In111 Pentreotide and In111 Leukocyte Scintigraphs all show increased uptake in FD, to the best of our knowledge there is only one case of FD in which Dual Phase Tc99mMIBI scintigraphy (DuPhTcMS) was compared with the findings of Tc99mMDP scintigraphy in the literature. AIM: The aim of this study was to compare the DuPhTcMS and Three Phase Tc99mMDP Bone Scintigraphy in the evaluotion of FD.Materials and Methods: Retrospective study of 5 cases (3 Females,2 Males) with histopathologically confirmed FD aged 19-65 years old evaluated with Three Phase Tc99mMDP Bone Scan and DuPhTcMS which were admitted to our hospital between 08.199903.2005.Results: In all patients both blood pool and late phase in the Tc99mMDP Bone Scans showed increased uptake in the lesions. However, DuPhTcMS findings are variable. A case of monostotic FD involving the mandibule and another case of polyostotic FD who underwent combined imaging, in both patients DuPhTcMS revealed no abnormal activity in FD lesions. On the other hand, the case involving the left maxilla/orbita and an other case with polyostotic FD showed retention of Tc99mMIBI on delayed images in all of the lesions except for the occipital involvement. In the last patient early Tc99mMIBI images showed increased uptake in right femur was noted on Tc99mMDP Bone Scan. However, 2-hour delayed images revealed remarkable washout of Tc99mMIBI from the lesion. In this patient another proximal tibial lesion showed no pathological uptake both in early and late phase Tc99mMIBI images.Conclusions: Three Phase Tc99mMDP Bone Scan is useful in determining the extent of FD. It seems that the metabolic activity of the lesions may be evaluated more reliably as compared to bone scan that shows bone turnover. DuPhTcMS could be a useful diagnostic tool in the follow-up and monitoring response to therapy if our results are validated in a larger patient series.

P685 Scintigraphic detection of suspected fractures M. A. Balsa Breton, M. P. Garcia Alonso, F. J. Penin Gonzales, C. Peyillera; Hospital Universitario de, Madrid, Spain. Initial diagnostic evaluation for suspicious fractures, traumatic or not, is made with plain radiographs, but in some localizations or aetiologies they are negatives in earliest times. Fails to recognize this fractures results in delayed diagnosis and treatment. The trauma surgeons, every time with more frequency, require a bone scintigraphy for early and accurate diagnosis. The aim of this study was review retrospectively the bone scan performed for suspected fractures with negative radiographs. PATIENTS AND METHOD: Over a year and a half period, two-phase bone scan with 99m-Tc-HDP was performed, from at least 48 hours following the earliest symptoms, in 71 patients with clinically suspected fractures at: 24 scaphoides (14 males and 10 females) 13 feet: 8 metatarsus, 1 finger, 2 calcaneus and 2 tarsus (7 males and 6 females) 9 ribs (5 males and 4 females) 22 hips (5 males and 17 females with average age of 73 years) 2 coccyges (1 male and 1 female) 1 clavicle (a boy 3 years old) Results: In 11of 24 carpus the bone scan was negative for fracture, in 6 proved scaphoid fracture and in 7 fractures in other bone carpus. In the feet it was positive for fracture in 7/8 metatarsus, 1 finger, 1 calcaneus and 2 tarsus. The 9 ribs, 2 coccyges and 1 clavicle were diagnosed as fractures. Of the 22 patients with suspected occult hip fractures, in 5 the bone scan was normal, and in 17 it showed fracture (6 sub-capital fractures and 11 other pelvic fractures).Conclusions: Early bone scintigraphy is a sensitive, reliable and cost-effective examination in cases of suspected fractures when the radiographs are normal or equivocal, enabling a more effective treatment.

P686 The incidence of pseudo costal resection appearance on routine bone scintigraphy

Clinical Science: Bone & Joints

G. G. Durmus-Altun, U. Can, D. Bedel, Y. Kutucu, S. Berkarda; Trakya University, Edirne, Turkey.

P683

AIM: Lung cancer is the third pathology for incidence of bone metastasis. Bone scintigraphy is both more sensitive and more specific than plain radiography or CT for the detection of bone metastases. If one considers the local extension as one of the most relevant prognostic parameters. This work aims to analyze the incidence of pseudo costal resection (PCR) as a marker of sever local extension of lung cancer.Methods: The study group included consecutive 106 patients with small cell (SCLC) or non-small cell (NSCLC) lung cancer (101 male, 5 female, mean age 57±11 yrs). All patients reviewed for the presence of metastasis, and pattern of bone metastasis was recorded basis of the localization, number and activity of foci. The histological type of lung cancer was also recorded. Metastatic foci were verified with histological, radiological or clinical follow up.Results: Forty-four of 106 patients have metastatic foci, 29 of them located on thorax bones. 20 out of them have osteolytic bone lesion anywhere of body and only 10 patients have PCR, one of SCLC and remaining 9 patients were NSCLC. All patients with PCR have multiple metastases. The incidence of PCR observed by bone scintigraphy in lung cancer is about 9.4%.Conclusions: The present knowledge noted that evidence of metastasis in lung cancer patients is a severe prognostic signal. The incidence of costal resection appearance in routine bone scintigraphy is about 10%.

Bone scintigraphy findings in endemic skeletal fluorosis M. Yildiz, S. Cerci, H. Suslu, M. Ozbek; SD University Medical Faculty, Isparta, Turkey. Endemic skeletal fluorosis is a chronic metabolic bone disease by an excess of fluoride in the water. Fluoride is retained in the bones and induces hardening of all the bones. Hypertrophy of the joints and bones is seen. Bone scintigraphy is more sensitive in the diagnosis of bone diseases than clinical examination and conventional radiologic imaging. Serum calcium, inorganic phosphorus, total alkaline phosphatase, creatinine, blood urea nitrogen were analyzed and whole body bone scintigraphy was performed in 25 patients with skeletal fluorosis. Serum calcium, inorganic phosphorus, total alkaline phosphatase, creatinine, blood urea nitrogen were found to be normal in all subject Skeletal scintigraphic findings revealed incresed radiotracer accumulation in axial skeleton (92%), costachondral joints (80%), hip joints (72%), knees (84%),

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How is the irradiation effect on the distraction osteogenesis H. Kaya1, C. Kesemenli2, B. Kaya3, S. Necmioglu2, H. Buyukbayram4; 1 Dicle University School of Medicine Department of Nuclear Medicine, Diyarbakir, Turkey, 2Dicle University School of Medicine Department of Orthopaedics and Traumatology, Diyarbakir, Turkey, 3Dicle University School of Dentistry Department of Oral and Maxillofacial Surgery, Diyarbakir, Turkey, 4Dicle University School of Medicine Department of Pathology, Diyarbakir, Turkey. Aim: The aim of the study to investigate the effect of the radiotheraphy on the distraction osteogenesisMaterials and Methods: Twenty-five New Zealand rabbits were divided into an experimental and a control group. The experimental group distal half of the left tibia with adjacent fibula of each animal were irradiated with Co 60 teletheraphy machine. Co 60 was not administrated to the control group. Study group and control group was kept in a similar environment. After four weeks, an osteotomy was performed on the left tibia in the diaphyseal region in both groups. The distraction was continued until an increase of 10 mm was achieved. At weeks 4, 8,12 and 16, radiography, scintigraphy and biopsy were performed in both groups and the results were statistically analysed.Results: The study group was not shown meaningful osteoblastic activity and bone healing. The bone healing and the osteoblastic activity were significantly greater in the control group at weeks 4,8,12 and 16.Conclusions: It seems that distraction osteogenesis are not successful in irradiated bones.

P688 Sternal normal variant patterns with respect to age on bone scintigraphy e. özdemir, f. aydo÷an, s. türkölmez, k. demirel, g. koca, m. korkmaz; ankara training and research hospital, ankara, Turkey. Aim: Sternum displays various radioactivity (RA) uptake patterns on bone scintigraphy. Staging of malignities is based on differentiation of these patterns from true metastases. The aim of this study was disclose the patterns of sternal RA uptake in patients without sternal pathology and to evaluate the distribution of these uptake patterns among various age groups. Material-method: Bone scintigraphies from 239 patients (131 male, mean age = 41 ± 21 [1-90]) without known malignities and sternal pathology were evaluated retrospectively. The patterns of sternal RA uptake were classified into 4 groups as; Homogenous, Focal Hot Spots (FHS), Focal Hypoactive Areas (FHA) and Segmented Appearence (SA). The distribution of these patterns among different age groups was evaluated by dividing the patients into 5 age groups as; Children (1-12 years [n = 26]), Adolescants (13-18 years [n = 21]), Young adults (19-40 years [n = 57]), Adults (41-60 years [n = 89]) and Geriatrics (> 60 years [n = 46]).Results: Homogenous pattern, FHS, FHA and SA were present in 36 %, 17 %, 23 % and 24 % of the patients, respectively. The distribution of these patterns among the 5 age groups defined was statistically significant. Children displayed 23 (88.5 %) homogenous and 3 (11.5 %) FHS patterns. The SA pattern was present in 62 % of adolescants. Focal hypoactive areas were never seen in children and adolescants. Almost equal frequencies of distribution was present in the adult age group. Focal hypoactive areas tended to be more frequent with increasing age so that in the geriatric age group, FHA was seen in 45.7 %, SA pattern in 23.9 % and FHS in only 6.5 % of the patients. Focal hot spots appeared on the angle of Louis in 67.5 %, the manubrium in 25 % and the corpus in the rest of the cases. On the other hand, FHAs were detected on the xiphoid in 80 % and on the corpus in 20 % of the patients.Conclusions: Patterns of sternal RA uptake on bone scintigraphy display age related variations. Focal hotspots tend to appear on the manubrium and the angle of Louis, whereas FHAs appear more evidently on the xiphoid and the corpus. This information may help in the differential diagnosis of RA uptake on the sternum.

P689 Mandibular Condylar Hyperplasia: a pictorial review. O. Adesanya, A. Notghi; City Hospital, Birmingham, United Kingdom. Aim: To illustrate the imaging appearances of condylar hyperplasia, with emphasis on SPECT bone scintigraphy and quantitative uptake. Although mandibular condylar hyperplasia is rare, it is one of the most common temporo-mandibular joint growth abnormalities. It is said to have equal sex incidence, but females tend to present more frequently for treatment as a result of facial asymmetry. Other symptoms are usually related to malocclusion and TMJ dysfunction. Presentation is usually in the second and third decade of life. Although, the inherent structure of the bone is unchanged, there is unilateral enlargement of the neck and condyle of the mandible. This may or may not be accompanied by subsequent sclerosis and remodelling. The histological change includes the persistence into adulthood or resumption of activity of primitive mesenchymal cells, a hypertrophic cartilage layer and the presence of cartilage islands in the bony trabeculae. There are several theories regarding the aetiology. These include exuberant repair in response to trauma or malignancy, infection and excessive loading. Symptoms usually begin once the contralateral side stops growing. Imaging modalities used in the evaluation of mandibular condylar hyperplasia include plain radiography; radionuclide bone scans with SPECT and quantitative uptake and SPECT/CT. We describe varied radiographic and scintigraphic appearances of this condition. It is important to remember other differential diagnoses that may mimic its appearance, including osteochondroma of the mandibular condyle.

P690 Bone scintigraphy after the treatment of the bone cyst where BAS-O bioactive glass ceramic was used. 1

2

2

1

1

E. Urbanova , P. Sponer , K. Urban , J. Vizda ; Nuclear Medicine, University Hospital, Hradec Kralove, Czech Republic, 2Orthopaedic Surgery, University Hospital, Hradec Kralove, Czech Republic. The aim of this study was to assess the role of bone scintigraphy in long-term follow up patients where BAS-O bioactive glass ceramic in the treatment of bone cyst was used. Bioactive ceramics

were reported to have the character of osteoconduction and capability of bonding directly with the living bone tissue. All these ceramics contain calcium and phosphorus in their composition. It is believed that dissolution of both calcium and phosphate ions are necessary for ceramics to form an apatite layer on their surfaces and to bond directly with the bone.Methods: 20 patients (pts.) were treated by curettage and filling of the bone defect with bioactive glass-ceramic between October 1990 and January 2000. Patients were in age range 8-23 years. The primary diagnoses: aneurysmal bone cyst in five pts. unilateral bone cyst 11pts., and four pts. with fibrotic dysplasia. The anatomical distribution of these cysts indicated metapfyseal region in eight pts., and diaphyseal region in 12 pts. Clinical examination, plain radiograph and 3-phase bone scintigraphy and SPET were performed to follow up the patients after the operation. Scintigraphic data were acquired with dual head gamma camera. 3-phase bone scintigraphy was performed after i.v. administration of 370-740 MBq 99mTc-MDP (methylendiphosphonate). All data were evaluated by the processing system Xpert-Pro and visual interpretation and semiquatitative analysis was done. Regions of interest (ROI) were selected bilaterally in consecutive four coronal slices and compared to equivalent reference ROI.Results: In all patients were no serious changes in perfusion and blood pool. Normal osteoblastic activity in implanted area was in eight patients (cysts were in proximal metaphyseal region) slightly increased in five pts. High activity was present in seven cases (these pts. suffered pain and cysts were located in diaphysis). No signs of glass-ceramic loosening and no periostal reaction were observed on plain radiographs. Clinical examination proofed no bacterial inflammatory changes of the soft tissues in all cases.Conclusions: The best results were found in the group of patients treated for bone cyst in the proximal metaphyseal region of the femur. It is area with dominant pressure exertion. This small study suggest that BAS-O bioactive glass ceramic is not suitable filling material for cyst in diapfyseal region. 3-phase bone scintigraphy and semi-quantitative SPET analysis are sensitive methods to follow up patients after aneurysmal or unicameral bone cyst operation for monitoring bony repair after surgery.

P691 The contribution of 99mTc-hydroxymethylene diphosphonate scintigraphy to the etiological diagnosis of acute renal failure secondary to mild rhabdomyolysis V. Esnault, M. Nakhla, C. Delcroix, M. Moutel, O. F. A. J. Couturier; University of Nantes, Nantes, France. Purpose: We tested whether bone scintigraphy could help the etiological diagnosis in patients with mild rhabdomyolysis, since different patterns of soft tissue radiotracer uptake have been found on bone scintigraphy in patients presenting severe rhabdomyolysis, with a localized asymmetric pattern in traumatic lesions and a more diffuse and symmetric pattern in nontraumatic lesions. However, the performance of bone scintigraphy in mild rhabdomyolysis is unknown. Furthermore, the etiological diagnosis of rhabdomyolysis can be difficult, particularly in alcohol abusers who deny a recent alcoholic binge.Methods: A bone scintigraphy was performed in sixteen patients presenting with an acute renal failure secondary to mild rhabdomyolysis (CK levels ” 36,000 IU), with obvious causes in ten cases and with uncertain etiologies in the remaining six patients.Results: In five cases with evident traumatic rhabdomyolysis, and in four patients with uncertain etiologies, bone scintigraphy showed localized asymmetric soft tissue radiopharmaceutical uptake compatible with traumatic lesions. None of the five patients with non traumatic rhabdomyolysis had significant soft tissue radiopharmaceutical uptake. In one patient with traumatic rhabdomyolysis, the bone scintigraphy performed only 11 days after the initial insult was negative. One patient with uncertain etiology also had a negative scintigraphy.Conclusions: Bone scintigraphy, when performed early in the course of the disease, may contribute to the etiological diagnosis of rhabdomyolysis if it shows asymmetric localized soft tissue radiopharmaceutical uptake compatible with traumatic lesions. However, bone scintigraphy is often negative in mild non traumatic lesions.

P692 The significance of tc 99m-mdp bone scintigraphy in the articular involvement of behcet’s disease M. Yildiz, M. Sahin, E. Tunc, S. Cerci, H. Suslu; SD University Medical Faculty, Isparta, Turkey. Aim:Articular involvement was reported to be present in approximately 5-76% of Behçet patients. Thus, we need a useful non-invasive method to detect early articular involvement in Behçet patients with nonspesific clinical complaints. To evaluate the usefulness of Tc99m-MDP bone scintigraphy in detection of articular involvement of Behçet’s disease.Materials and Methods:Bone scintigraphy with Tc 99m-MDP was performed in 32 consecutive patients with BD (17 male, 15 female). The clinical manifestations of disease were recorded and routine laboratory tests were performed. Three-phase sacroiliac joint and whole body bone scintigraphies were performed. Results:Despite, joint complaints were present in 8 (25%) patients; we detected joint involvement by scintigraphy in 27/32 (84.4%) Behçet patients mostly affecting the knees (62.5%), ankles (59.4%), sacroiliac joints (25%), wrists (21.9%), shoulders (18.7%), elbows (12.5%) and hips (3.1%). Involvement of large joints was more prevalent. Four of the articular involvement was monoarticular and the remaining was oligoarticularDespite, our Behçet patients were clinically asymptomatic and had normal pelvis radiography, sacroiliitis was found in 8 patients (25%) and 4 of which was bilateral. Conclusion: Bone scintigraphy is more sensitive in the diagnosis of joint involvement than clinical examination or conventional radiological imaging, allowing earlier diagnosis and showing the presence of articular involvement in multiple sites. Bone scintigraphy can be used in patients with BD to determine the presence of arthritis, especially in sacroiliac joints, even asymptomatic.

P693 Sintigraphic/Radiographic correlative evaluation of painful foot in the detection of acrometastasis G. S. Limouris1, K. Rousopoulos1, C. T. Panayides1, P. Sideras1, L. Lamprakos1, J. Kouvaris2, X. N. Papacharalampous2, A. Stavraka1, L. Vlachos2; 1University of Athens-Aretaieion Hosp, Radiology Dept, Nucl

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Med Div, Athens, Greece, 2University of Athens-Aretaieion Hosp, Radiology Dept, Athens, Greece. Aim: Foot acrometastasis is extremely rare accounting for less than 0.3 % of all osseous metastases, often misdiagnosed as a common arthritis. By the present , it is aimed to correlative evaluate the scintigraphic / radiographic imaging of painful foot-bone in patients (pts) with a known history of malignancy. Patients and Methods: In the last decade, approx 8000 whole body bone scintigraphies have been performed routinely in our Institute, on a follow up basis program, in pts with known history of malignancy in a dosage of 740 MBq of Tc-99m MDP for each scan, given intravenously. In cases of a positive foot-bone scan, pts were encouraged to undergo a correlative study by CT or MRI.Results: Only 15 foot acrometastases up to day have been detected out of 8000 bone scans, performed the last decade and only 1 was proved as a talus metastasis.Conclusions: Pain in foot-bone in pts with known history of malignancy should be considered as potential metastasis. Correlative imaging by CT and / or MRI is a ‘must’ and has to follow scintigraphy in order to differentiate pain.

P694 199

Tl-chloride scintigraphy in the differential diagnosis of non-specific inflammations and malignant neoplasms of locomotor system V. Zavadovskaya1, A. Kourazhov1, O. Kilina1, E. Choinzonov2, V. Chernov3, Y. Lishmanov3, E. Slonimskaya2, O. Radionova1; 1Siberian State Medical University, Tomsk, Russian Federation, 2Institute of oncology, Tomsk, Russian Federation, 3Institute of cardiology, Tomsk, Russian Federation. The aim: to determine criteria of differential diagnosis of non-specific inflammations and malignant neoplasms of locomotor system using 199TL-chloride. Material and methods. We studied 18 patients (10 males, 8 females aged 19-78 years) having inflammatory (n=12) and tumoral (n=6) locomotor system diseases. Results were verified morphologically (n=11), compared with X-ray study (n=16), CT (n=15), 3-phase bone scan (n=7). Primary (n=3) and metastatic (n=3) neoplasms were verified morphologically in all patients. Planar scan (185MBk 199 Tl-chloride) was performed in the early (20 minutes) and late (180 minutes) phases. Intensity of 199Tl-chloride accumulation in pathologic focus and clearness of its contours were defined visually. Quantitative assessment included definition of ER and DR180 which are terms «zone of injury/intact contralateral or adjacent area» (L/C or L/R) and retention index (RI180=DR180/ER). Results. Basic signs of differential diagnosis of locomotor system non-specific inflammations and malignant neoplasms were RI180 and changing clearness of external contours of 199Tlchloride pathologic uptake. In the early phase of the study, non-specific inflammations were visualized as foci of increased accumulation of 199Tl-chloride high (n=7), moderate (n=3) and low (n=2) intensity. In the late phase of the study, the intensity decreased from high to moderate (n=5), from moderate to low (n=1) or preserved high (n=2), moderate (n=2) and low (n=2). In 10 of 12 patients RI180<1.0 and clearness of external contours of increased accumulation of markers was more in the early phase compared to the late one. In 2 patients having chronic inflammations the value of RI180 approximated to 1.0 and clearness of external contours of pathologic uptake of 199 Tl-chloride in dependence on the study phase changed not significantly. All malignant neoplasms were visualized in the early phase of the study as areas of 199Tl-chloride increased accumulation of high (n=1), moderate (n=1) and low (n=4) intensity which in the late phase increased from low to moderate (n=4), from moderate to high (n=10 or did not change (n=1). RI180 was>1.0 in all cases and clearness of external contours of the marker pathologic uptake was observed better in the late phase of the study than in the early one. ER was statistically more higher in patients having inflammatory diseases of locomotor system compared to patients having malignant neoplasms (p<0.05); value of DR180 did not differ possibly because of small size of observations. Conclusion. 199Tl-chloride scintigraphy showed high efficacy (16 of 18 patients, 88.9%) of differential diagnosis of non-specific inflammations and malignant neoplasms of locomotor system.

P695 Radionuclide diagnostic of the foot osteomyelitis in diabetes mellitus patients V. Zavadovskaya, O. Kilina, A. Kourazhov, G. Dambajev, A. Abu-Jabal; Siberian State Medical University, Tomsk, Russian Federation. The aim of the study was to assess efficacy of radionuclide methods of diagnosis to reveal osteomyelitis in the setting of diabetic osteoarthropathy. Material and methods. We studied 44 patients having diabetes mellitus of the 1-st type (n=13) and of the 2-nd one (n=23) with diabetic foot. All patients underwent X-ray study and 21 patients underwent 3-phase bone scan (3FBS). 19 patients underwent specific scintigraphic study of purulent infection focus using WBC-99mTcHMPAO and 22 patients underwent using non-specific scintigraphic study using 199Tl-chloride. Scintigraphic studies were performed with planar gamma-camera using collimators of 140 keV and 300 keV, 740 MBk of 99mTc and 185 MBk of 199Tl. Obtained results were verified by operative intervention (n=27) and compared with dynamic observation results (n=17). Results. The 3FBS results showed low specificity of this method to detection of inflammation in the setting of diabetic foot (60.0%); bone scan criteria of osteomyelitis were revealed in patients with and without destructive-lytic changes of the osseous tissue. Increasing specificity of osteomyelitis diagnosis in the patients with diabetic foot was reached by additional use scintigraphy with specific and non-specific inflammation radiotracer. WBC-99mTc-HMPAO scan gave true-positive (TP) results in 13 patients and 199Tl-chloride scintigraphy gave those in 12 patients. Absence of the indicator accumulation in the region of interest was the cause of truenegative (TN) results in 9 patients. False-negative (FN) results were due to the error of blood labeling method (n=3). One FP results of WBC-99mTc-HMPAO scan and 5 FP results of 199Tlchloride scintigraphy were obtained in patients, with localization of inflammation in soft tissues and histologic study did not confirm inflammation in adjacent bone. FN results independently on accumulation mechanism was due to the difficulty of differentiated recording of the indicator accumulation in the soft tissues and foot’s bones because of small sizes of the study subject. 199 Tl-choride scintigrapty resulted in specificity of 75%, sensitivity of 83% and accuracy of 77%. WBC-99mTc-HMPAO scan did not differ significantly from those of 199Tl- chloride scintigraphy and were 86%, 80% and 89% respectively. Conclusion. 3FBC has rather low specificity to reveal osteomyelitis in diabetes mellitus patients. Specific and non-specific inflammation indication

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methods allow increase to sensitivity and specificity in diagnosis of osteomyelitis in the patients with diabetic foot; their similar diagnosis efficacy was noted.

P696 Radionuclide methods osteomyelitis

in

the

diagnostics

of

chronic

O. Kilina, V. Zavadovskaya, A. Kourazhov, O. Radionova, T. Berezina; Siberian State Medical University, Tomsk, Russian Federation. The aim of the study was to compare the diagnostic effectiveness of radionuclide methods in revealing chronic osteomyelitis exacerbation. Material and methods. We studied 19 patients (12 males, 7 females mean age 43.2±9.7 years,) having chronic hematogenic osteomyelitis exacerbation (n=9), post-traumatic and post-operative osteomyelitis (n=10). X-ray study revealed osteosclerotic processes without line periostitis and clear signs of sequesters. Scintigraphy study included 3-phase bone scan (3FBS) and scan with autologous leucocytes labeled 99mTc-HMPAO (WBC-99mTc-HMPAO scan) (n=11 and n=19, respectively). The studies were performed using planar gamma-camera with the collimator of 140 keV, 740 MBk of 99mTc. Scintigraphy results were verified by morphologic investigation of operation material (n=6) and compared with dynamic observation data (n=13). Results. The 3FBS revealed exacerbation of chronic osteomyelitis in 8 of 11 patients studied. Osteomyelitis exacerbation was verified in 5 patients by operative treatment data (n=2) and KT data; 3FBS results were assessed as TP ones. Osteomyelitis presence was not verified in 2 patients and 3FBS results were assessed as FR ones in 1 patient with osteoidosteoma (by CT data) and in 1 patient with marked purulent inflammatory process in soft tissues of intact bone. Presence of inflammation based upon 3-phase bone scan was rejected in 3 patients (TN). 3FBS sensitivity to diagnose chronic osteomyelitis was 100%, specificity 75%, accuracy 73%. WBC-99mTc-HMPAO scan data were considered as chronic osteomyelitis exacerbation in 12 patients. Subsequently, osteomyelitis was verified in 11 patients by operative treatment data (n=4) and CT data (n=7); WBC-99mTc-HMPAO scan results were assessed as TP ones. WBC-99mTc-HMPAO scan data did not verify osteomyelitis presence in 1 patient (FN). In this case, purulent-inflammatory was localized in soft tissues and contiguous bone remained intact. WBC-99mTc-HMPAO scan data did not verify our assumption concerning intraosteal inflammation in 7 patients (5 TN and 2 FN results). The diagnostic effectiveness of WBC-99mTc-HMPAO scan in indication purulent intraosteal inflammation was high: sensitivity, specificity and accuracy were 86%, 92% and 84% respectively. Results of WBC-99mTc-HMPAO scan and 3FBS were in accordance in 7 patients and were not in 4 patients. Conclusion. WBC99m Tc-HMPAO scan in combination with 3FBS to revealing chronic osteomyelitis allows to decrease number of FP results, especially in patients with post-traumatic and post-operative osteomyelitis and to increase rate of specificity and accuracy of the investigation

P697 Blood pool bone scintigraphy (BPBS) in the evaluation of active knee osteoarthritis (OA) and its relation with the type of pain I. P. Iakovou1, B. Makris2, D. L. Presti1, P. Markou3, D. Chatzopoulos1; 1 Nuclear Medicine dpt. Papageorgiou hsp, Thessaloniki, Greece, 2 Orthopedics dpt. Papageorgiou hsp, Thessaloniki, Greece, 3Biomedica, Thessaloniki, Greece. General: Bone scintigraphy is an important tool for staging and follow-up in patients with joint disease, allowing judgement of inflammatory, soft tissue components of joint disease (arthritis). The indication for radionuclide synovectomy (RS) is based on both clinical symptoms and on proven hyperperfusion, with active synovitis being seen on a pre-therapeutic three-phase bone scan. Aim: To evaluate sensitivity and positive predicted value (PPV) of a positive BPBS in diaforodiagnosis of inflammatory joint disease activity.Methods: 205 knee joints with OA of 115 patients (71±3.7years old) referred for RS treatment enrolled in this study. All joints were clinically evaluated, classified by X-ray Steinboecker system and type of pain (only under stress/ both under stress and rest). Two-phase bone scintigraphy was performed after i.v. injection 99m Tc-MDP according to the procedure guidelines of our department and intensity of tracer accumulation in joints was scored independently by two experienced observers.Results: Osteoarthritic joints were x-ray graded 29.3% as I, 36.1% as II, 22,9% as III and 11,7% as grade IV. The ț-values describing excellent intra-observer variability were 1 with dichotomous and 0.86 with a 3-point scale criterion. BPBS had a sensitivity of 0.91, specificity of 0.63, PPV of 0.93 and NPV of 0.56 in our sample with high prevalence of pain (0,84). X2trend analysis revealed a strong association between the intensity of a positive BPBS and rest pain no matter the Steinboecker grading.Conclusions: BPBS is a useful technique, with very good intra-observer agreement, in the assessment of the active inflammatory knee OA. The intensity of tracer accumulation is strongly related to the type of pain (only under stress/ both under stress and rest).

P698 Validation and intra-observer agreement in two-phase bone scintigraphy (TPBS) of knee joints with osteoarthritis (OA) P. Markou1, I. P. Iakovou2, B. Makris3, D. L. Presti2, D. Chatzopoulos2; 1 Biomedica, Thessaloniki, Greece, 2Nuclear Medicine dpt. Papageorgiou hsp, Thessaloniki, Greece, 3Orthopedics dpt. Papageorgiou hsp, Thessaloniki, Greece. AIM: TPBS is a valuable method detecting synovitis in knee joints with severe osteoarthritis. However only a few data are available concerning its validation and intra-observer agreement in OA. The aim of our study was to evaluate the clinical usefulness of blood pool (BP) and static scan (SS) in respect with observer agreement with different criteria and with stress joint pain, clinical and x-ray findings. MATERIAL METHOD: 57 patients, (20 men) 66±10 years old referred for radio-synovectomy of knee joints due to severe OA, were studied. Overall, 105 knee joints were clinically evaluated, radiography classified by Steinboecker system and TPBS. Twophase bone scintigraphy was performed after i.v. injection of 600 MBq 99mTc-MDP as follows: blood pool phase between 1.5 to 5 min p.i ; static phase 3 h p.i. All results were evaluated blinded and independently by two experienced observers. The intensity of tracer accumulation in

joints on bone scans was scored with a) a dichotomous (presence/absence) criterion and b) with a 3-point scale (absent, mild and intense accumulation). Interrater agreement was calculated using kappa (ț) statistics.Results: The joints with (and without) pain were radiographically graded as 0.0% (6.7%) grade 0, 24% (53,3%) as I, 41,3% (23,3%) as II, 21,3% (13,3%) as III and 13,3% (3,3%) as grade IV. Of all knee joints studied 71% were painful, 65% had radiography graded II or more, 88% had BP and 84% SS with pathological findings. The ț-values describing intraobserver variability between BP and SS were 0.78 and 1 with dichotomous and 0.77 and 0.81 with a 3-point scale criterion, respectively. Good agreement was found between BP and SS with a dichotomous (ț = 0.63) rather than 3-point scale (ț = 0.39) criterion. However, the presence or absence of pain had better agreement with SS (ț = 0.76) than BP (ț = 0.57). BP had a sensitivity of 0.93, specificity of 0.6, PPV of 0.85 and NPV of 0.81. The sensitivity and specificity of SS was 0.95 and 0.43, with PPV 0.81 and NPV 0.77.Conclusions: Our study confirms the importance of TPBS in assessment of knee OA with high prevalence and the very good intraobserver agreement.

P55 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Lung P702 Pulmonary calcifications in hemodialysis patients detected by Tc-99m diphosphonate scening

The findings of bone scintigraphy in the patients with Ankylosing spondylitis K. Demirel1, M. Korkmaz1, S. Türkölmez1, G. Koca1, E. Özdemir1, B. Tönük2, R. Yorgancıo÷lu3; 1Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey, 2Department of Physical Medicine and Rehabilitation, Abant Izzet Baysal University, School of Medicine, Bolu, Turkey, 3Department of Physical Medicine and Rehabilitation, Ankara Training and Research Hospital, Ankara, Turkey. Aim: The aim of this study was to investigate the value of bone scintigraphy in the patients with Ankylosing spondylitis (AS).Methods: 26 patients (7 female, 19 male; mean age 37.9 years, age range 19-65 years) with AS were included in the study. A three-phase MDP bone scintigraphy was obtained in all of patients. In order to calculate the sacroiliac joint index (SII), same pixel wide rectanguler region of interest (ROI) were placed on sacrum and on each sacroiliac joint (SIJ). SII was found by dividing the avarage counts of the respective sacroiliac joint by the avarage counts obtained from the sacrum. The sacroiliac joints with SII higher than 1.35 were diagnosed as sacroiliitis (SI).Results: Sacroiliitis was found in 76.9% (20/26) of patients. In 18 of these patients were detected bilateral SI. Sacroiliitis in the young patients with AS was significantly higher than the older patients. In the 7 (35%) of patients with SI was showed increased perfusion on the SIJ. Hyperemia was detected in 11 (55%) of patients with SI. Twentytwo patients (85%) had activity in one or more sites of the cervical, thoracic, or lumbar spine on planar imaging. Abnormal activity was observed in the cervical spine in 6 patients (23%), in the thoracic spine 22 patients (85%), and in the lumbar spine in 20 patients (77%). 13 patients had increased activity in the thoracic costovertebral junctions. Joint involvements were detected in the ankle in 6 patients (23%), in the shoulder in 5 patients (19%), in the hip in 4 patients (15%), and in the knee in 3 patients (12%). The enthesitis was found in 6 patients.Conclusions: The results demonstrated that spinal involvements, SI, polyarthropathy, and enthesitis are frequently found in patients with AS. We recommend that bone scintigraphy can be used in patients with AS to determine the presence of skeleton involvements.

P700 Diagnostic value of uptake index in separating septic and aseptic arthritis with 99mTc ciprofloxacin scintigraphy: Preliminary study Military Medical

99m

Tc-ciprofloxacin (99mTc-CIP), a quinolone antibiotic drug is used as a specific agent allowing differentiation between infection and sterile inflammation. The results are usually interpreted by visual analysis of scintigraphy images. AIM: Patients with suspected hip and knee infection (n=16) underwent scintigraphy in order to distinguish bacterial infection from aseptic inflammation (nonspecific uptake), using 99mTc-CIP. PATIENTS and METHODS: We compared the images obtained in two groups of patients: patients with infected (n = 10) and not infected (n = 6) joints. In group with infection, there were six patients with orthopedic prosthesis. After iv. injection of 555 MBq 99mTc-CIP we made images at 5min, 1h, 4h and 24h. We also calculated ratio of accumulation with average counts/pixel on pathological and contralateral healthy side in all times of imaging. Visual estimate of pathological joints was used and as well semiquntitative method with uptake index calculation. We tried to define cut off value of the index that would help us to diagnose bacterial infection.Results: We found in nine out of ten patients with confirmed bacterial infection index value equal or higher than 2.0 (mean value 2.4). The index values in hip region were slightly lower than in knee joint. All six patients without joint infection had index value below 2.0.Conclusions: Preliminary results showed that use of the semiquntitative method for uptake index calculation, in addition to visual evaluation, may improve the accuracy of method.

P701 The value of bone scintigraphy in the evaluation of swelling at the costochondral junction K. Demirel, G. Koca, D. Cayır, S. Türkölmez, E. Özdemir, M. Korkmaz; Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey. Aim: The aim of this study was to investigate the value of bone scintigraphy in the evaluation of swelling at the costochondral junctionMethods: Sevently patients (48 female, 22 male; mean age 24.2 years, age range 15-64 years) with swelling at the costochondral junction were included. In all of patients, findings of plain radiographs were normal. Patients with a history of known bone pathology, surgery, or chest deformity as well as a history of any malignancy were excluded. Three phase MDP bone scintigraphy were obtained in all patients. Results were compared with clinical follow-up.Results: Complaints of swelling at the costochondral were more frequent in the younger women. Complaints was generally defined at the anterior end of the second or third rib.

Z. Rajkovaca1, P. Kovacevic2, A. Matavulj2, N. Ponorac2; 1Clinical Centre, Department of Nuclear Medicine, Banja Luka, Bosnia and Herzegovina, 2 Department of Physiology, Medical Faculty, Banja Luka, Bosnia and Herzegovina. Pulmonary calcification is a complication of chronic renal failure, which may be a significant etiology of pulmonary dysfunction. End-stage renal disease (ESRD) patients receiving chronic hemodialysis (HD) often develop unexplained pulmonary hypertension (PHT) which etiology is not jet clear. This study evaluated whether scanning with 99m-technetium diphosphonate (DPD) might visualize pulmonary calcifications.Methods: The study population consisted of 35 patients (25 males and 10 females, aged 29-71, mean 49 +/- 9 years) with end-stage renal disease, who were treated by regular hemodialysis with signs and symptoms of cardiorespiratory failure. After chest X-ray evidence of cardiomegaly and persistent bilateral nodular lung densities with no evidence of pulmonary calcification they were prospectively studied by routine laboratory analyses, whole body scintigraphy with 99mTc DPD (555 MBq), pulmonary function testing (spirometry) and level of parathyroid hormone.Results: Out of 35 patients 20 (57.1%) had increased lung uptake of 99mTc DPD on whole body scintigraphy (group 1). These patients were on dialysis 146 +/- 28 months compared with 54 +/- 14 months in 16 patients with a normal lung uptake (group 2) (p<0.01). Age, sex, blood pressure, hematocrit, hemoglobin, serum calcium, phosphorous, bicarbonate, magnesium, urea, creatinin, alkaline phosphatase did not differ between this two groups. Out of 20 patients from group-1 18 had significantly lower (p < 0.01) ventilatory function (FVC, FEV1, FEF75, FEF50, FEF25) compared with 5 patients from group-2. There was statistically insignificant difference between this two groups regarding parathyroid hormone level (p>0.01).Conclusions: Lung uptake with 99mTc DPD may be employed effectively to help establish an early diagnosis of pulmonary calcification especially in high risk dialysis patients which may be associated with an abnormality in pulmonary function.

P703 Case Report: Functionally amputed upper lobe in left lung [Unilateral Lobar Swyer-James (Macleod's) Syndrome] T. Öneú, B. Çalıúkan, T. Laçin, F. Dede, T. Y. Erdil, S. ønanır, M. Yüksel, H. T. Turo÷lu; Marmara University, Istanbul, Turkey. INTRODUCTION: Swyer-James Syndrome (SJMS) is an uncommon disease linked to repeated episodes of childhood respiratory infections.This syndrome is generally diagnosed with a chest radiography showing hyperlucency at childhood in patients who are symptomatic. However, in some patients who are relatively asymptomatic, the diagnosis may not be made until later life. We wish to report a patient with a history of repeated pulmonary infections in childhood who demonstrated classical findings of SJMS in only one lobe. V/Q scan showed markedly diminished perfusion and ventilation in left upper lobe which was like a surgically resected lobe. CASE: A 34-year-old man was admitted to hospital with dyspnea and chest pain. The patient had an old CXR which was obtained in late childhood which demonstrates shift of mediastinum, trachea and heart towards to the right side and a dense opacity throughout the left upper lobe. Chest examination showed diminished breath sounds over the left hemithorax. A CXR obtained on admission showed mediastinum, trachea and heart shifted towards to the right side. The upper side of left lung was hyperlucent and showed a marked diminution in the number of vascular markings on CXR. Fiberoptic bronchoscopy revealed no obstructing lesions. The number of major bronchi on the left was normal. V/Q scan showed markedly diminished perfusion and ventilation in the left upper lobe. There was no evidence to suggest pulmonary embolism ant the perfusion of the right lung was noted as normal. A HR-CT of the chest with contrast revealed loss of normal anteroposterior attenuation gradient and marked air-trapping at the left upper side with a reduced vascularity. Pulmonary arteries were seen bilaterally and the bronchial tree was patent.Results: These findings are consistent with those of SJMS. DISCUSSION: The V/Q scan seems to be more sensitive than radiography and CT scan in detecting affected lung regions and superior in showing their extent and distribution in this patient.

P704 Scintigraphic detection of intrapulmonary arterio-venous shunts in patients with liver cirrhosis D. Sobic-Saranovic1, S. Pavlovic1, D. Culafic2, M. Perisic2, P. Rebic3, V. Artiko1, V. Bosnjakovic4, V. Obradovic1; 1Institute of Nuclear Medicine, Belgrade, Serbia and Montenegro, 2Institute for Digestive disease, Belgrade, Serbia and Montenegro, 3Institute for Lung diseases and TB, Belgrade, Serbia and Montenegro, 4Sanu, Belgrade, Serbia and Montenegro. Aim: Abnormal pulmonary perfusion pathways with shunting trough small dilated pulmonary vessels may be detected in some patients with liver cirrhosis using perfusion lung scintigraphy. We studied 50 pts in order to detect intrapulmonary arterio-venous pulmonary shunts.Methods: Hepatological studies included laboratory liver function tests, Doppler ultrasonography and histopatological diagnosis. Two groups of pulmonary function tests were applied: the

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D. Pucar, Z. Jankovic, S. Dugonjic, B. Ajdinovic; Academy, Belgrade, Serbia and Montenegro.

In all of patients showed no abnormal MDP uptake in the costochondral junction sites. In all of these patients were not detected bone pathology on costochondral localisation for mean 12 months follow-up.Conclusions: In patients with swelling at the costochondral junction, bone scintigraphy is usually normal. It is a benign condition usually of short duration that resolves completely.

measurements of respiratory gas concentration in the arterial blood (in supine and sitting position) and ventilation tests (spirometry, flow volume curve and body pletismography). Morphologic studies included standard chest X-ray radiography and perfusion scintigraphy using intravenously injected technetioum-99m-macroaggregated albumin (MAA) in sitting position. After completion of lung scintigraphy in 4 standard projections, planar brain and kidney scintigraphy was also performed.Results: Orthodeoxia (the fall of PaO2 during the position change from supine to sitting) had been confirmed in 9 out of 50 pts. Lung scintigraphy showed 99mTc-MAA in the brain and kidney in the same pts. The patients with prominent oxigenation disorders tended to have more severe liver insufficiency. In the case of mild hypoxemia intrapulmonary shunts were absent.Conclusions: In patients with liver cirrhosis and prominent hypoxemia intrapulmonary right-to-left shunts represent a major pathogenetic mechanism in the development of severe respiratory disorder.

P705 Evaluation of the effect of passive smoking on alveolocapillary permeability with Tc-99m DTPA aerosol scintigraphy G. Koca, F. Aydogan, S. Türkölmez, D. Çayır, E. Özdemir, K. Demirel, M. Korkmaz; Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey. Aim: In various studies it has been shown that smoking results increasing in pulmonary epithelial permeability. In this study, it is aimed to determine whether there is an improvement in the pulmonary epithelial permeability in passive smokers after giving up smoking using Tc-99m DTPA aerosol scintigraphy.Materials and Methods: Fifteen active smokers, 15 passive exsmokers (with a history of cigarette smoking period and 5 ± 1.5 years mean duration of smoking withdrawal but still living as passive smokers) and 15 nonsmokers totally 45 volunteers (30 male, 15 female, mean age 33.9±10.8 were included in the study. Following the inhalation of 35 mCi Tc-99m DTPA for 3 minutes dynamic lung images were obtained in posterior position for 30 minutes. Clearance half times (t 1/2 ) were calculated for both lungs by placing a monoexponential fit on the curves. Mean t 1/2 values of three groups have been compared by Tukey test.Results: Age and gender distributions were similar in three groups. Mean clearance half times of smoker, non-smokers and passive-ex smokers were 27±9.6 minutes, 66.50 ±23.9 minutes and 67.30 ± 23.9 minutes respectively. There were significant differences in between mean clearence half times on smokers and nonsmokers(p <0.001) and smokers and passive smokers (p <0.001). But no significant difference was determined between nonsmoker and passive smoker group(p: 0.099).Conclusions: This study shows that there has been an evident improvement in the lung alveolo-capillary permeability in passive ex-smokers. In case of expassive- smoking status and Tc-99m DTPA aerosol scintigraphy can be used as an non-invasive method for revealing the improvement of pulmonary epithelial permeability in this group.

P706 The analysis deposition

of

inhaled

Tc-99m

DTPA

aerosol

lung

S. Ogi1, E. Goto1, M. Uchiyama1, M. Urashima2, N. Fukumitsu3; 1Dept. of radiology, Jikei University School of Medicine, Tokyo, Japan, 2Division of Clinical Research & Development, Dept. of Pediatrics, Jikei University School of Medicine, Tokyo, Japan, 3Proton Medical Research Center, University of Tsukuba, Ibaraki, Japan. Aim: Tc-99m DTPA radioaerosol scintigraphy can be evaluated transport system of ciliated epithelium in the proximal airways and the permeability of the alveolar capillary membrane. We investigated whether the mucociliary clearance influence to the evaluation of the alveolar capillary membrane clearance. Materials and methods: Thirty eight patients(19 male, 19 female; mean age: 50.8±21.6 years) with interstitial pneumonia(IP) or suspected IP were evaluated in this study. Tc-99m DTPA aerosol inhalation scintigraphy was performed and halftime (T1/2) of DTPA clearance were calculated by placing a mono-exponential fit on the curves. T1/2 was categorized into 6 groups (Group 1: clearance from all lung field included the hilar proximal airways, Group 2: clearance excluded 5X5 pixels of hilar proximal airways, Group 3; clearance excluded 8X8 pixels, Group 4; clearance excluded 11X11 pixels, Group 5; clearance excluded 14X14 pixels, Group 6; clearance excluded 17X17 pixels).The data were expressed as mean±SD and kruskal-Wallis equality of populations rank test was used for the comparison of each groups. Results: T1/2 values of each group were 41.2±24.9 min for Group 1, 39.9±21.6 min for Group 2, 39.7±19.1 min for Group 3, 39.8±17.7 min for Group 4, 40.1±17.3 min for Group 5 and 41.5±18.7 min for Group 6. There was no significant difference in the T1/2 of DTPA clearance between each group(p=0.481). Conclusion: Tc-99m DTPA clearance from peripheral alveolar capillary membrane does not influence the clearance from ciliated epithelial transport system of proximal airways.

P707 Dispersion by mechanical ventilation of a zone of alveolar edema studied by 99mTc-Albumin scintigraphy. 1

2

2

3

1

1

D. Le Guludec , N. de Prost , J. Ricard , D. Dreyfuss , G. Saumon ; EA 3512, Bichat Hospital, Paris, France, 2Bichat Hospital, Paris, France, 3Louis Mourier Hospital, Paris, France. Introduction. Mechanical ventilation modality affects patient outcome, through ventilatorassociated lung injury and/or systemic dissemination of sepsis and inflammation during bacterial pneumonia. Perfluorocarbons (PFC) or surfactant have been proposed as adjuncts during mechanical ventilation or as vectors of antibiotics for the topic treatment of pneumonia. Thus, interactions between ventilation, PFC or surfactant and alveolar edema fluid are important issues. Material and methods. A stable zone of alveolar flooding was produced instilling 200 µl of hypertonic (x 2) mannitol solution labeled with 99mTc-albumin in rat distal airways. Conventional ventilation (CV) was applied for 30 min followed by different ventilation strategies for 3 hours: CV with 8 ml/kg VT (n = 10), spontaneous breathing (n = 8), partial liquid ventilation with 2 (n = 8) or 4 ml PFC, 0.5 ml surfactant (n = 8) or saline (n = 6) instillation, 8 cmH2O positive end-

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expiratory pressure (PEEP), high VT (24 ml/kg) with (n = 6) or without PEEP (n = 5). Intrapulmonary and systemic dissemination of the tracer were continuously (150sec/image) recorded during 3 hrs by scintigraphy (dedicated small animal gamma camera, Gamma Imager Biospace). Results. CV, spontaneous breathing, surfactant or saline did not disperse alveolar flooding. Ventilation with a large VT and no PEEP promoted homo and contralateral dispersion of the tracer. PEEP stabilized the zone of flooding during large VT ventilation. Ventilation with a large VT induced systemic leakage of the tracer. Partial liquid ventilation with 4 ml PFC induced a transient intrapulmonary dispersion and some systemic leakage of the tracer. Conclusion. High VT ventilation influences the spatial dispersion of a zone of alveolar flooding in the absence of PEEP and rapidly increase alveolar albumin permeability. PEEP may thus lessen bacterial dispersion during ventilation of patients with pneumonia. This study also suggests that PFC and alveolar edema liquid have a limited interaction which questions the use of PFC as a vector for the topical treatment of pneumonia.

P708 Imaging pulmonary embolus in pregnancy: Experience from two University Hospitals K. Irfan1, E. Soh2, S. Yates3, Y. Du1, S. Chua1, H. Cheow4, N. Screaton5, J. 1 Bomanji1, P. Ell1, A. Groves1; UCL, London, United Kingdom, 2 Addenbrooke's hospital, Cambridge, United Kingdom, 3Addenbrookes Hospital, Cambridge, United Kingdom, 4Addenbrooke's Hospital, Cambridge, United Kingdom, 5Adenbrooke's Hospital, Cambridge, United Kingdom. Aim It can be difficult to choose between ventilation/perfusion (V/Q) scintigraphy or computed tomography pulmonary angiography (CTPA) in investigating pregnant patients for suspected pulmonary emboli (PE). Foetal radiation exposure is lower from CTPA, whilst maternal breast exposure is higher. Recent meta-analyses generally favour CTPA over lung scintigraphy. However, in pregnancy there are technical difficulties in using CT and there is concern over contrast-media effects to the foetus. The aim of this study was to assess possible changes in practice in PE diagnosis during pregnancy over the last 6-years from two University Hospitals. Material and methods We reviewed the computerised records of two teaching-hospitals from1999-2005 with respect to patients being imaged for suspected PE. The number of CTPA and lung scintigraphy studies performed during pregnancy year-by-year and the test-results were recorded.Results: Institution-One;1999/00 10, 0, 10: 2000/01 06, 0, 06: 2001/02 24, 0, 24: 2002/03 10, 1, 11: 2003/04 04, 3, 07: 2004/05 10, 5, 15. There were 21 V/Q studies, 44 (5 halfdose) perfusion-only studies. Five scintigrams and one CTPAs were positive. One patient underwent both investigations neither were positive. Institution-Two;Lung scintigraphy numbers then CTPA numbers then total numbers. 1999/00 18, 2, 20: 2000/01 19, 2, 21: 2001/02 21, 2, 23: 2002/03 13, 5, 18: 2003/04 11, 3, 14: 2004/05 10, 8, 18. Seventy-nine patients underwent perfusion-only and 3 full-V/Q studies. Three scintigrams and no CTPAs were positive. Three patients underwent both investigations, neither were positive. Conclusions: With respect to the overall total number of studies performed for suspected PE in pregnancy, there was no time trend. CTPA usage has increased in pregnancy, but lung scintigraphy is still more commonly used. Only a small proportion of pregnant patients investigated were diagnosed with PE.

P709 Comparison of diagnostic performance of lung scintigraphy and CT angiography for pulmonary embolism K. Hwang1, S. Choi2, M. Yoon1, W. Choi1; 1Department of Nuclear Medicine, Gachon University Gil Medical Center, Incheon, Republic of Korea, 2Department of Radiology, Gachon University Gil Medical Center, Incheon, Republic of Korea. Objectives: Lung scan and CT angiography (CTA) are important diagnostic modalities for diagnosis of pulmonary embolism (PE)., but their results frequently shows discrepant results. We investigated the discordant findings between lung scan and CTA in diagnosing PE.Methods: Thirty two patients who performed both lung scan and CTA to diagnose PE were enrolled (male:female=15:17, mean age:54). Segmental pulmonary arteries with emboli on CTA and mismatching perfusion defects were compared and analyzed based on segments.Results: A total of 335 segments were positive on either lung scan or CTA. Lung scan detected 75% of all defects and CTA found 74%. 26% of all defects concordant on lung scan and CTA. Defects on lower or posterior lung had a tendency to show relatively high discordant rate and those on upper or anterior lung showed relatively high concordant rate.Conclusions: In diagnosis of PE, lung scan and CTA show some discrepancy and the discordant findings may depend on the segmental location of defect. Keywords: Pulmonary embolism, Lung scan, CT Angiography.

P710 Pulmonary embolism: correlation between perfusion scintigraphy results and ct findings.

ventilation-

B. Rodriguez-Alfonso, C. Rodríguez-Rey, R. Sanchez-Sanchez, A. Ortega-Candil, L. Bañuelos-Andrio, E. Carmona-Asenjo, J. MucientesRasilla, L. Izarduy, J. Carreras-Delgado, L. Lapeña-Gutierrez; Hospital Clinico Universitario San Carlos, madrid, Spain. Aim Pulmonary embolism (PE) is a common disease with 500000 new cases/year in USA. An accurate diagnosis is greatly important since with effective treatment mortality decreases from 30% to 7%. Our purpose was to evaluate the agreement between the two imaging techniques that are usually required in our hospital for the diagnosis of PE, which are helical CT and ventilationperfusion scintigraphy (V/Q Sc). Material and Methods Retrospective evaluation of patients who underwent a CT and V/Q Sc for PE diagnosis during 2005. Cases with lack of essential data in the clinical history or with an interval greater than 5 days among the studies were excluded. The CT studies were performed in a helical CT 15-20 seconds after the i.v. injection of iodinated contrast in order to ensure the visualisation of pulmonary artery. The ventilation scan was obtained after the application of 99mTc-O4- Technegas (370MBq) in a dual-head gammacamera. Perfusion scintigraphy was done immediately after with 370 MBq 99mTc-labeled

P711 Correlations between clinical diagnostic testing, spiral ct and ventilation-perfusion lung scannig E. Garcia, J. Martinez, J. Rodriguez, B. Llana, C. Roiz, N. Zeidan, A. Alvarez, T. Allende; Hospital Central de Asturias, Oviedo, Spain. Objective: To evaluate possible correlations between results obtained from clinical diagnostic testing and ventilation-perfusion lung scanning.Materials and Methods: Sixty consecutive patients (pts) with high-probability ventilation-perfusion lung scan (V’/Q’scan) results (using the PIOPED criteria) were screened. Ventilation lung scanning was performed after inhalation of 35 mCi Tc99m DTPA aerosol and perfusion lung scanning was performed after an IV injection of 6 mCi Tc99m MAA using the Elscint Helix dual-head gamma camera. Clinical and instrumental diagnostic procedures included chest X-rays (CXR), electrocardiograms (ECG, 49 cases), echocardiograms in 20 patients, D-dimer tests (48 pts, ELISA assay, cut-off level 275 ng/ml), and arterial blood gas abnormalities (46 cases). Spiral computed tomographic angiography was performed in 35 pts using a General Electric Lightspeed Plus CT. Results: Unexplained dyspnoea and pleuritic chest pain were the most frequent symptoms (90%) reported. The most frequent CXR abnormalities were opacifications of the costophrenic angles and elevated hemidiaphragm, either or both in 65% of pts. Electrocardiogram results were abnormal in 57% of pts: 76% had signs of acute right ventricular overload. In 33% of the cases, transthoracic echocardiograms detected dilated right heart chambers. Plasma d-dimer concentrations were >1000 in 88%. Arterial hypoxemia (pO2< 80) was found in 77% of the pts and pCO2<35 in 43%. 95 % of the pts with alkalosis had bilateral perfusion defects in lung scans. V’/Q’ scans were positive in 25 pts (42%), who did not undergo the spiral CT. Perfusion scans detected bilateral defects in 70% and multiple defects in 80% of the cases. 10% of the pts had normal spiral CT results. Only three sub-segmental defects were described. 52% had bilateral defects of the lungs (positive spiral CT) and 38% had unilateral intraluminal defects. The lower lobes were the most frequently affected (43%). Conclusions: 1- 67% of the pts had negative CXR; therefore this alone does not exclude PE. 2- Signs of acute right ventricular overload were the most frequent abnormalities present in ECG, echocardiography does not usually support additional information. 3- Our study showed good correlation between arterial blood gas analysis and the extension of the defects in perfusion lung scans. 4- The d-dimer assay had a high negative predictive value, as described in previous publications. 5- The lung scan was more sensitive than the spiral CT in diagnosing PE, probably because of its capacity to detect sub-segmental perfusion defects (<25% of a segment).

P56 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Miscellaneous P712 Prevalence and characteristics of sicca syndrome among patients with chronic HCV infection attending Kasr El Aini hospital in Egypt

C virus infection, Sjögren's syndrome, Lid parallel conjunctival folds, Tear film break-up time, sialoscintigraphy, dactoscintigraphy.

P713 Validity of Quantitative Salivary Gland Scintigraphy Parameters in Patients with Sjögren’s syndrome in comparasion to Normal Subjects S. Dugonjic, B. Ajdinovic, D. Stefanovic, D. Pucar; Academy, Belgrade, Serbia and Montenegro.

Military Medical

Sjögren’s Syndrome (SS) is chronic autoimmune inflammatory disease in which salivary and lacrimal tissue undergo progressive destruction by lymphocytic infiltration, resulting in reduction of salivary and lacrimal function. Dynamic salivary gland scintigraphy (DSGS) is one of the oral tests which are used in European Diagnostic Classification Criteria for SS, to evaluate oral component of disease. Early diagnosis of salivary function damage in SS patients enables correct diagnosis and therapy. The aim of study was to evaluate and compare quantitative salivary gland scintigraphy parameters (QSGSP) in patients with SS and normal subjects. MATERIAL AND METHODS: Twenty SS patients and ten normal subjects underwent DSGS. DSGS was performed after iv. injection of 370 MBq Tc99m-petrechnetate with gamma camera above parotid (PG), submandibular salivary glands (SG), and oral cavity. DSGS lasted 60 minutes (one frame-one minute), with per os stimulation in 40. minute with ascorbic acid tablet. Time-activity curves (TAC) were generated over PG and SG as regions of interest. From TAC the following QSGSP were calculated: Tmax.-time of maximal accumulation; MA-maximal accumulation; AV-accumulation velocity, as parameters of salivary gland accumulation; MS-maximum secretion, MSS-maximum stimulated secretion; SSV-stimulation secretion velocity and Tmin.time of minimum activity, as parameters of secretion. RESULTS: MA and AV as accumulation parameters, and all parameters of secretion (MS, MSS, SV and Tmin.), of parotid glands function significantly differ in SS patients from normal subjects. All scintigraphic accumulation and secretion parameters of submandibular salivary glands function significantly differ in SS patient from normal subjects. CONCLUSION: Evaluated quantitative salivary gland parameters are sensitive enough to detect salivary function damage and to distinguish normal subjects from SS patients and enabling early diagnosis of SS.

P714 Histopathologic and semiquantitave analysis of abnormal salivary glands in patients with Sjogren's Syndrome. T. Aksoy, P. Kiratli, B. Erbas; Hacettepe University, Ankara, Turkey. Purpose: The aim of this study was to test the diagnostic ability of semiquantitative parameters of dynamic salivary gland scintigraphy in patients with histopathologically evaluated Sjogren's syndrome (SS). Patients and Methods: Twenty-eight patients (range: 25-75 yrs) suspected of having SS were studided. All patients had histopatholojical evaluation of biopsies from minor labial salivary gland. Severity of histological changes was graded according to the Chisholm and Mason scoring system. Dynamic images were obtained for 20 minutes after i.v. injection of 555 MBq 99mTc-pertechnetate and for another 20 minutes after oral lemon juice stimulation. Regions of interest (ROI) were drawn over the submandibular glands (SMG), parotis glands (PG), thyroid (T) and background at the right temporal. Time activity curves for all ROIs were generated. Count rates were obtained for the first minute (FM), 15th minute (15m), maximum (Max), minimum (Min) activity after lemon juice stimulation and last minute (L). Functional parameters were calculated for each salivary gland as; FM/Max, Max/Min, T/Max, T/15, Max/L, 15/L, and Excretion Fraction (EF%). According to histopatological grading, the patients were divided into two subgroups. Of 28, 15 patients with Grade-0 and Grade-1 biopsy were accepted as normal or with minimal changes (Group I) and 13 with grade 2-4 were accepted as advanced stages of SS (Group II). The difference between the calculated semiquantitative parameters was tested using ANOVA testResults: There were no significant difference between Group I and II for EF values of parotid glands (Group I: LPG= 54%±15, RPG=55%±12 and Group II: LPG=42.3%±18, RPG= 46.8%±19, respectively). However, Group II had significantly decreased EF values (LSMG=25±25, RSM=30,5±12) for SM glands compared to Group I (LSMG=46±10, RSM=46,5±13) (p<0.008 and p<0.003). Other quantitative parameters could not differentiate between Group I and Group II.Conclusions: Semiquantitative analysis of salivary gland scintigraphy provides further information on the decreased secretion velocity in the submandibular glands. EF value seems to be a sensitive and valuable parameter for the differantiation of patients with pathological secretion function in the submandibular glands.

A. M. A. A. Amin, 1990; Cairo University, Cairo, Egypt. Objective: To describe the prevalence and characteristic of sicca syndrome in patients with chronic HCV infection and to study the association between the sicca syndrome and the clinical, and laboratory features of the liver disease. Patients & methods: we examined 120 patients with chronic hepatitis C infection attending Kasr El Aini hospital in Egypt. Subjective and objective criteria of xerophthalmia and xerostomia were investigated. The function of the lacrimal glands was assessed by: Tear film break-up time (BUT), Lid parallel conjunctival folds (LIPCOF), Schirmer’s test, Rose Bengal dye test and dactoscintigraphy. The function of the salivary glands was assessed by: sialoscintigraphy. Results: 79 patients (65.8%) had sicca syndrome; 66 patients (55%) had xerophthalmia & xerostomia as documented by DSG, sialoscintigraphy& ophthalmologic tests while 13 patients had xerophthalmia without xerostomia. Most of SS patients were asymptomatic, only 10.1% had symptoms of sicca syndrome. None of our patients had anti-Ro or anti-La. The presence of SS was associated with older age (r= 0.28, P= 0.00), female gender (P=0.001), cirrhosis (r=0.34, P=0.000) but not with the viral load (r= 0.19, P= 0.06). There was association between SS and both thrombocytopenia (r= 0.72, P=0.000) & rheumatologic manifestation (P=0.000). There is a positive correlation between the results of dactoscintigraphy and the results of ophthalmologic tests (r = 0.87) & (P 0.0000).Conclusions: Prevalence of SS in patients with chronic HCV infection in Egypt was high & most of them were asymptomatic; so clinicians should routinely follow the HCV-infected patients, paying sufficient attention to the presence of SS. LIPCOF test for the diagnosis of xerophthalmia is a sensitive indicator for the presence of dry eyes. Dactoscintigraphy is an objective, practical, and noninvasive method & appears to be useful for the assessment of the function of lacrimal glands. Salivary scintigraphy is relatively safe, well tolerated, and easy to perform, and enables a quantitative assessment of the function of all major salivary glands. Key words: chronic hepatitis

P715 Evaluation of gastric emptying following sleeve gastrectomy using radioisotopique techniques S. I. Koukouraki, M. I. Stathaki, D. Filis, M. Daboudi, I. Melissas, N. Karkavitsas; University Hospital, Iraklion, Crete, Greece, Iraklion, Greece. Aim : The purpose of this study was to evaluate a new operative technique “ sleeve gastrectomy” for treatment of morbidity obese patients, using radioisotopique techniques. Materials-Methods: 14 pts morbidly obese (aged 18-55 years) subjected to operative management using sleeve gastrectomy were enrolled in this study. The inclusion criteria was BMI >40 or >35 with severe co-morbidity. This new technique was performed laparoscopically in all patients and the greater curvature of the stomach was cleared from the omentum and short gastric vessels starting 7cm away from pylorus up to cardioesophageal junction. Laparoscopic stepplers was then used to divide the fundus and part of the body of the stomach. Scintigraphies were performed with a camera GE Millennium, provided with a LEGP collimator. Patients injests a radiolabeled solid meal with 1mCi 99mTc-SC. Anterior static images were performed for 90 min. Semiquantitative analysis was used to evaluate the solid gastric emptying. ROIs were drawn around the stomach in each image and counts were opbtained.Results: All 14 pts underwent preoperative scintigraphy and six of them had a scintigraphic follow up 6 months postoperatively. All of 14 pts had a slow gastric emptying in the interval of 90 min (43%-56%) in the preoperative scan. In the follow up

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macroaggregated albumin administered i.v. over two respiratory cycles in supine position. An experimented radiologist classified the CT studies as positive, negative or non-conclusive. The V/Q studies were analyzed by an experimented nuclear physician by applying PIOPED criteria. Final diagnosis was obtained according to clinical follow-up of at least 3 months and the response to heparine treatment when applied. Results Sixty-seven patients underwent CT and V/Q Sc for PE diagnosis last year in our hospital. Fifteen were excluded. The total number of patients included was 52, mean-age 63.6 y. PE prevalence was 76.9%. Twenty eight cases were correctly diagnosed by both imaging modalities, 25 were positive for PE and in 3 patients PE was ruled out. In 14 cases the results of CT and V/Q Sc were discordant. PE was finally confirmed in 11 of these patients. Nine of them were accurately diagnosed by V/Q Sc and only 2 by CT. The 3 patients in which PE was finally excluded showed a high probability V/Q Sc and a negative CT. Five CT studies were inconclusive, 2 of them with a final diagnosis of PE and 3 without it. Five V/Q Sc scans showed an indeterminate probability of PE. As in the CT cases, 2 of them had a final diagnosis of PE. Conclusions In 53.8 % of cases V/Q Sc results correlated with CT findings. In cases of disagreement V/Q Sc had a higher sensitivity although CT reached a higher specificity.

postoperative scintigraphy a significant a fast gastric emptying was observed (70%-98%) (p< 0.05).Conclusions: Preliminary results showed that fast emptying of the solid foods following sleeve gastrectomy occurred 6 months postoperativly and this may stimulate gut hormonic and other unknown mecchanisms resulting in early satiety and weight loss.

P716 The importance of nuclear medicine in the hepato-pulmonary syndrome T. Mut Dólera, M. J. Torres, P. Bello, J. F. Martí, C. Ruiz, I. Asensio, C. Olivas, A. Rivas, R. P. Velasco, A. Mateo; H. U. La Fe, Valencia, Spain. The hepatopulmonary syndrome (HPS) is a vascular lung disease based on the presence of liver dysfunction, the existence of arterial hypoxemia and the demonstration of vascular lung dilations in absence of a cardiac-lung disease that could justify these findings. The only efficient treatment is liver transplant. Aim: To reflect the importance of the pulmonary scintigraphy with macroaggregated albumin (MAA) in demonstrating and quantifying the vascular pulmonary dilations’ degree in patients with HPS.Materials and Methods: We studied 8 patients (6 men, 2 women) with ages between 31 and 65 years (with a mean age of 51.6 years) who had compatible symptoms and signs with HPS (presence of chronic liver disease associated with hypoxemia: PaO2 < 70% mmHg and AaPO2 > 20 mmHg). We administrated 75-100 MBq of 99mTc-MAA, and obtained, 3-5 minutes post-injection, static images of thorax in an anterior projection, totalizing 500kc, and posterior and lateral views according to the time spent in the first image, using a general purpose collimator. We drew regions of interest around the brain and lungs, obtaining total counts, which were helpful for the calculus of the extra-pulmonary shunt fraction (ESF). This fraction is considered pathological if its value is > 6%, and it can be resumed with the following equation: ESF (%)= Brain Total Counts/ 0.13 x 100 (Brain TC/ 0.13) + Lung TC * where TC represents the total countsResults: In 3 of 8 patients (37.5%) we observed brain uptake with an ESF > 6%, (after turning down the idea of the presence of free 99mTc), so the study was considered positive for HPS. These patients were treated with orthotopic liver transplant; the scintigraphy realized after this treatment did not show brain uptake, demonstrating the patients’ recovery (ESF < 6%).Conclusions: Pulmonary scintigraphy with 99mTc-MAA is useful in the diagnosis of HPS, allowing the demonstration and quantification of vascular intrapulmonary dilations, as well as in the evaluation of the healing efficiency of the orthotopic liver transplant.

P717 The scintigraphic determination of peritoneo-pleural leakage in a case with massive hydrothorax G. Koca, F. Aydogan, M. Korkmaz, S. Türkölmez; Department of Nuclear Medicine, Ankara Training and Research Hospital, Ankara, Turkey. Aim: Massive hydrothorax is a rare but serious complication of continuous ambulatory peritoneal dialysis. Scintigraphy is an important method in demonstrating peritoneo-pleural leakage. This report is about a case with type II DM who had a leakage of dialysis solution to the pleural space from the peritoneal space.Materials and Methods: A fourty-five years old male patient with hypertension, type II DM, nephrotic syndrome, coronary artery disease and a prior coronary-by pass operation presented with edema refractory to medical therapy. Peritoneal dialysis was initiated by inserting a CAPD catheter and upon drainage failure, a chest radiogram was obtained which revealed pleural effusion up to the middle zone of the right lung. A scintigraphic examination was carried out with 37MBq (1mCi) Tc-99m sulphur colloid given by an abdominal catheter with dialysis solution. Dynamic and static images were taken. Late static images were taken after the drainage of the dialysis solution.Results: Peritoneo-pleural leakage in right hemithorax was confirmed in the scintigraphic evaluation. It is hard to establish the diagnosis of leakage from thorasynthesis material due to high glucose levels in diabetics. In this circumstance scintigraphy is recommended for evaluation of peritoneo-pleural relation. After the scintigraphic diagnosis of peritoneo-pleural leakage, 7500 cc of solution was drained by thorasynthesis and CAPD was given up, and hemodialysis was carried out.Conclusions: Scintigraphy is a noninvasive and reliable method for determination of the peritoneal leakage in patients undergoing peritoneal dialysis. The probability of peritoneo-pleural leakage must be considered, in the presence of solution in the lungs of the patient, and scintigraphy must be considered before biochemical assessment particularly in diabetic patients.

P718 Colour-coded Doppler sonography is not able to predict splenic function in comparison to scintigraphy with heat99m altered Tc-labelled erythrocytes. M. Gotthardt1, S. Bröker2, A. Schlieck2, A. Bauhofer3, M. Behe2, C. Goerg4, T. M. Behr2; 1Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands, 2Department of Nuclear Medicine, Philipps-University, Marburg, Germany, 3Institute of Theoretical Surgery, Philipps-University, Marburg, Germany, 4Department of Internal Medicine, Philipps-University, Marburg, Germany. Aim: The determination of spleen function is of importance to determine those patients that need prophylactic treatment with antibiotics to prevent sepsis. From the literature, it is not totally clear whether nanocolloid scintigraphy (NS) is sufficient or whether scintigraphy with heat-altered erythrocytes (ES) is necessary. We therefore compared these techniques and colour-doppler sonography (DS) in patients with IBD. Patients and Methods: NS, ES, and DS were performed in consecutive patients with inflammatory bowel disease (IBD) between 7 / 2002 and 3 / 2003. Clearance rates were determined in ES, ROI-based liver/spleen ratios (LSR) were measured in ES and NS. In DS, vascular resistance indices (VRI) were determined for central and peripheral splenic blood vessels as well as spleen size and echogenecity. Furthermore, the results of the different imaging techniques were compared to clinical activity scores for IBD and the course of the disease in every patient.Results: 35 patients were included into the study, 19 with ulcerative colitis, 14 with Crohn´s disease, and 2 with a mixed disease pattern. The blood clearance in ES showed a clear pattern for patients with good (2), impaired (1), or missing splenic function (0). These results showed a good correlation to SLR in ES according to the guidelines of McDowell

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and Newell for independent parameters (0.63, p<0.01). 45 min. clearance in ES and allotment of patients to groups 0, 1, or 2 dependent on splenic function correlated well (Spearman-rho 0.89, p<0.01). Furthermore, the 10min clearance in ES showed a high correlation with the clearance after 45 min (Spearman-rho 0.87, p<0.01). The LSR in ES at 2, 5, and 10 min correlated well with the outcome after 45 min (Spearman-rho > 0.9 and p<0.01 in all cases). A LSR > 3.4 was predictive for hyposplenia in ES while a LSR <1.2 showed normal splenic function. There is a grey zone between 1.2 and 3.4. There were no significant correlations to the results of NS, the VRI in DS, or the clinical parameters obtained. Furthermore, Howell-Jolly-bodies were not able to predict impaired spleen function in our patients. Conclusion: ES is the only technique able to reliably determine splenic function in patients with IBD. The clearance at 10 min reliably determines splenic function. LSR above 3.4 are predictive of hyposplenia while LSR <1.2 show normal function with a grey zone in between.

P719 Red Cell Mass indexing for Lean Body Mass assessed by Bioelectrical Impedance Analysis : preliminary results. G. Arsos1, E. Moralidis1, N. Boussios1, N. Karavida1, E. Mandala2, D. Boundas1, S. Georga1, C. Sideris1, C. Karakatsanis1; 1Dept of Nuclear Medicine, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece, 2D' Dept of Internal Medicine, Aristotle University Medical School, Hippokration Hospital, Thessaloniki, Greece. Aim : Red Cell Mass (RCM) measurement is essential for the diagnosis of Polycythemia Vera. However, as the results are traditionally expressed in ml of red cells per kg of total body mass (TBM), false negative results may be generated in overweight and obese patients. Indexing by body surface area may improve the situation but this variable is both physiologically irrelevant and inaccurate as a measure of body size, particularly in obese patients. Lean Body Mass (LBM), easily calculated by Bioelectrical Impedance Analysis (BIA), may offer a reasonable body size index for many physiological parameters. The aim of the present study was to compare RCM per kg of TBM with per kg of LBM results in a cohort of patients referred for investigation of erythrocytocis. Patients and methods : Sixty-nine patients (25 women) with erythrocytocis (Ht 51.8±4.9), aged 56.7±16.1 years, with body weight 79.9±16.8 kg and body mass index (BMI) 27.9±5.0 kg/m2 were submitted to RCM measurement with Cr-51-chromate according to the recommendations of the International Committee for Standardization in Haematology guidelines (1980). Impedance measurement was performed in all patients using a Bodystat 1500 MDD (UK) body composition analyzer, through two pairs of self-adhesive electrodes placed on the right hand and foot. LBM (in kg) was calculated using previously validated regression equations. RCM > 32 and 36 ml/kg TBM for men and women respectively were considered abnormal. Values > 43 ml/kg LBM were considered abnormal for both sexes (Berlin 2000). Results : Forty eight patients (69,6%) were overweight or obese (BMI >25 kg/m2). According to the ml/kg TBM indexing and sex specifications, 15 patients had abnormal high RCM. Using the ml/kg LBM criterion, 7 additional patients were classified as having abnormal high RCM thus increasing the number of abnormal results by 46.7%. No patient with abnormal RCM by the ml/kg TBM indexing changed to normal by the ml/kg LBM criterion. The additional 7 patients classified as abnormal by the ml/ kg LBM criterion had higher BMI than the 15 abnormal patients with the ml/kg TBM criterion (29.4 ±4.8 vs 24.7±3.4 kg/m2, Mann-Whitney p<0.05). Conclusion : Indexing RCM measurements by LBM significantly augments the detection rate of abnormal high RCM results compared to traditional indexing by TBM. This improvement is entirely due to the re-classification of overweight or obese patients. Introduction of LBM, easily assessed by bioempedence, should be adopted for RCM indexing.

P57 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

Clinical Science: Infection - Inflammation P720 67

Vertebral osteomyelitis with cold lesion on Ga scintigraphy D. Alize-Diaw, J. Hauet, P. Reboul, C. Maillard, P. Kotzki, V. Boudousq; Nimes University Central Hospital, Nimes, France Aim: 67Ga-citrate is a helpful radiopharmaceutical in the assessment of chronic bone infection especially vertebral osteomyelitis. Its investigation requires biologic results, standard radiography, CT-scan (computed tomography scanning), MRI (magnetic resonance imaging) and nuclear medicine. 67Ga scintigraphy improved the specificity of a bone scan. We report a case of infectious spondylitis detected by a cold lesion on Ga-67 scan.Materials and Methods: An old man with a transplant liver, HCV positive and dialysed (nephrotoxicity of ciclosporin), was admitted for a progressive increasing thoracic backache without fever. In order to reveal an infectious spondylitis CT-scan, MRI, bone scintigraphy (two phase studies), 67Ga citrate scintigraphy and 99mTc-HMPAO labelled leucocytes were performed.Results: Labelled leucocytes and 67Ga scan revealed together a cold lesion at the same localisation than 99mTc bone scintigrams. A diagnosis in favour of a vertebral infection were confirmed by the others techniques. With the antibiotherapy the patient got better.Conclusions: Photopenia with labelled leukocytes have ever been described in spine infection so 67Ga imaging was preferred. We showed that cold lesion with Gallium scintigraphy could equally occurred in vertebral infection.

P721 Nuclear medicine osteomyelitis

imaging

vs

MRI

in

early

vertebral

G. Meristoudis, V. Giannakopoulos, A. Tsaroucha, T. Liotsou, C. Batsakis, A. Balomenos, D. Akrividou, J. Christacopoulou; Dept of Nuclear Medicine, “Sotiria” Hospital, Athens, Greece. Introduction: Although MRI is the method of choice in the investigation of Vertebral Osteomyelitis (VO), its diagnostic value has been questioned especially in the early phase of the disease, which is critical, as delay may have serious consequences. Aim of the study was to

TP

TN

FP

FN

DBS/ GaS

14

9

0

2

MRI

13

7

2

3

67

TP - True positive; TN - True Negative; FP - False Positive; FN - False Negative

Calculated sensitivity and specificity for DBS/ 67GaS was 87,5% and 100% compared to 81,2% and 77,7% for MRI. Fourteen out of 16 patients with VO had positive DBS/67GaS. Moreover DBS/67GaS showed in five patients additional sites of infection {(sacroiliac joint (n=1), sacroiliac joint and soft tissue abscess (n=2), paravertebral abscess (n=1) and rib osteomyelytis (n=1)}. None of the patients without VO had positive DBS/67GaS. Thirteen of the patients with VO had positive MRI studies. MRI correctly diagnosed the two missed by DBS/ 67GaS, however it was false negative in 3 cases and false positive in 2. Conclusions: From this limited sample of patients we can conclude that DBS/ 67 GaS has an excellent specificity in the diagnosis of early osteomyelytis. Both methods have equal sensitivity, and their role must be considered as complementary. However DBS/ 67GaS has the additional advantage of demonstrating other sites of infection which are not available from the MRI study.

P722 FDG PET findings of Retroperitoneal Fibrosis M. Nakajo1, S. Jinnouchi1, H. Tanabe2, R. Tateno1, M. Nakajo2; 1Atsuchi Memorial Clinic PET Center, Kagoshima, Japan, 2Department of Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan. Material and methods: Six patients with RF seen over a 3-year period were evaluated with FDG-PET or PET/CT. The diagnosis of RF was made by means of CT or surgical biopsy. PET studies were performed before steroid therapy in five patients, and under steroid treatment in the remaining one patient. FDG-PET imaging was performed at 1 hour after injection (early image). After an interval of 1 h, a second scan (delayed image) was acquired in four of five pre-treatment patients. Both early and delayed PET or PET/CT images were evaluated visually and semiquantitatively by calculating standardized uptake values (SUVs).Results: In five pretreatment patients, PET demonstrated high FDG uptake in the peri-aortoiliac region and the accumulation increased with time in four patients. The maximum SUVs on early images of these five patients ranged from 4.9 to 7.6, and the average maximum SUVs were 6.0. The maximum SUVs on delayed images of four patients ranged from 5.9 to 8.2, and the average maximum SUVs were 7.6. In the remaining one patient under steroid treatment, no pathological accumulation was seen in the retroperitoneal mass. There were other sites of abnormal FDG uptake in three of five pre-treatment patients. In two patients, PET demonstrated high FDG uptake in the pancreas. The maximum SUV of the pancreas increased on delayed image in one patient, and remained constant in the other patient. They were diagnosed as autoimmune pancreatitis by CT findings and clinical data such as increased serum Ȗ-globulin or IgG levels. In the remaining one patient, PET demonstrated mild FDG uptake in the mediastinum. The maximum SUV of the mediastinum was stable over the time. The diagnosis of fibrosing mediastinitis was made on the CT findings.Conclusions: FDG-PET could be a reliable means of evaluating disease activity and establishing the sites of involvement in retroperitoneal fibrosis patients.

P723 Clinical value of FDG PET/CT for the diagnosis of FUO in HIV+ patients C. Castaigne1, M. Dusart2, M. Tondeur1; 1CHU Saint-Pierre, Brussels, Belgium, 2PET-Scan IRIS, Brussels, Belgium. Aim : Retrospective evaluation of the usefulness of FDG PET/CT in patients affected by human immunodeficiency virus (HIV+) and suffering from fever of unknown origin (FUO) Material and methods : 10 HIV+ patients (6 males, 4 females, age 24-48) suffering from FUO were studied by PET/CT. Final diagnosis was established either by microbiological or histopathological analysis or by a more than 6 months follow-up. PET/CT was regarded as “helpful for diagnosis” when the abnormal uptake pointed to the organ or location where the cause of fever was thereafter identified or when it was normal and no pathological process was found during followup.Results: 9/10 PET/CT were abnormal and the cause of fever was further demonstrated using other diagnostic procedures. An infectious process was diagnosed in 6 patients (tuberculosis), a neoplasm in 3 (2 lymphomas, 1 Kaposi’s sarcoma). PET/CT directly suggested sites for biopsy in 6 patients (tuberculous lymphadenitis and neoplasm). The only patient with normal PET/CT suffered from drug-induced fever. None PET/CT was false positive.Conclusions: PET/CT is a valuable tool in HIV+ patients with FUO. PET/CT detected infectious or tumoral foci and oriented the sites for biopsy when a histopathological analysis was needed. Moreover, PET/CT allowed the initial staging in cases of lymphoma. We are conducting a prospective study in order to confirm these preliminary results.

P724 Tc-99m V-DMSA SPECT for the diagnosis of active Graves’ ophthalmopathy

M. Reyhan, O. S. Bakiner, O. Toygar, A. Sukan, M. Aydin, A. F. Yapar; Baskent University, Adana, Turkey. Background and Aim: Differentiation of the active orbital inflammation from inactive form is important in the treatment management of the patients with Graves’ ophthalmopathy (GO), because the patients benefit from immunosuppressive or radiotherapy in the active stage. The aim of this study was to assess the value of Tc-99m V-DMSA scintigraphy for the diagnosis of active stage of Graves’ ophthalmopathy (GO).Materials and Methods: Twenty-three patients (16 women and 7 men; mean age 41 ± 13 years with a range of 17-67 years) with GO and 12 control subjects (6 women, 6 men; mean age 52 ± 13 years with a range of 28-68) were included in the study. Four hours after i.v. injection of 740 MBq (20 mCi) Tc-99m V-DMSA anterior planar and SPECT images of the orbits were acquired. Ophthalmopathy was evaluated by physical examination, ophthalmometry, and magnetic resonance imaging. Disease activity was assessed by the presence of acute inflammatory signs: spontaneous retrobulber pain, pain on eye movement, eyelid erythema, conjunctival injection, chemosis, swelling of the caruncle, eyelid edema. Visual and semi-quantitative analysis of all data was performed by two observers. Semiquantitative evaluation was made by scoring the degree of radioactivity uptake in both orbit. Grading was performed as 0= no uptake; 1=slightly increased uptake from the background; 2= moderate uptake, less than nasal activity; and 3= severe uptake, equal to or more than the nasal activity.Results: Five of 21 patients were clinically active, and the remaining 18 patients were clinically inactive. Two patients from the clinically active group were semiquantitatively classified as grade 2, and the remaining 3 patients were grade 3. Eleven patients among the clinically inactive group were in grade 0 and the remaining 7 patients were in grade 1. There was no patient in grade 2 or 3 among the clinically inactive GO group. Ten of control subjects were scintigraphically classified as grade 0, and the remaining 2 patients were scored as grade 1. None of the control subjects had grade 2 or 3.Conclusions: Our results revealed that Tc-99m V-DMSA is a promising agent for the diagnosis of active GO.

P725 99m

Tc Exametazime brain scintigraphy - an atypical method of diagnosis of brain infections in HIV infected patients

M. Cambrea1, C. Cambrea2, C. Marcas3, V. Ionescu4; 1Nuclear Medicine Department, Euromedic, Constanta, Romania, 2Infectious Diseases Clinic, Faculty of Medicine, Constanta, Romania, 3Infectious Diseases Clinic, Clinical Infectious Diseases Hospital, Constanta, Romania, 4MRI/CT Department, Euromedic Romania, Constanta, Romania. Aim: To determine brain modifications at HIV infected persons.Materials and Methods: Study about 14 patients HIV infected with cerebral toxoplasmosis and cytomegalovirus (CMV) infections (serologically confirmed by ELISA for Toxoplasma gondii and cytomegalovirus). In two cases we detect DNA CMV by PCR from cerebrospinal fluid. We also performed a MRI brain examination and a brain scintigraphy with 350 MBq 99mTc Exametazime (67Ga-Citrate is not commercialized in Romania). The images were acquired with a General Electric Millennium dual head camera and processed on a General Electric eNTEGRA 2.5202 System.Results: We diagnosed 14 HIV infected patients, by clinical symptoms and serology, with cerebral toxoplasmosis (5 cases) and cytomegalovirus infections with cerebral localization (9 cases). At 9 patients serology for CMV was positive: in 2 cases IgM CMV and in 7 cases IgG CMV. At 7 patients MRI brain examination shown a normal aspect without pathological changes in brain and ventricles and at two patients we found typical lesions of ventriculo-encephalitis. We also perform a SPECT study with 99mTc Exametazime and at all patients we found lower tracer uptake in all cerebral area. At the other 5 cases serology for Toxoplasma gondii was positive (high titer of IgG Toxoplasma gondii). MRI brain examination has high intensity target lesions (which suggest toxoplasmosis) and at SPECT study we found absence of tracer uptake in the same areas.Conclusions: 99mTc Exametazime brain scintigraphy even doesn’t mention typical changes for CMV cerebral infection is a helpful investigation that complete diagnosis and can sustain/argue some clinical manifestation when MRI brain examination shown a normal aspect.

P726 Extrapulmonary tuberculosis in Norway. Diagnostic imaging and findings D. M. Solheim1, L. Borgen2, M. Haakonsen3, T. E. Gudmundsen4; 1 Department of nuclear Medicine, Sykehuset Buskerud, Drammen, Norway, 2 Department of Radiology, Sykehuset Buskerud, Drammen, Norway, 3 Deartment of Radiology, Sykehuset Buskerud, Drammen, Norway, 4 Department of Radiology, Sykehuset Buskerud and Buskerud University College, Drammen, Norway. Aim: To describe the current diagnostic imaging methods in detection of extrapulmonary tuberculosis. Background: During the last three decades the number of tuberculosis cases has declined among native Norwegians, but has increased among immigrants. The total number of tuberculosis cases declined until the mid-1990s, but increased thereafter. The percentage of immigrants among Norwegian tuberculosis patients increased from 5% in the 1970s, to almost 80% today. The largest increase has been among Asian and African immigrants, Somalians being the largest group. Even though pulmonary tuberculosis is the most common form, extrapulmonary tuberculosis, most frequently affecting bone and joints, is also relatively common and often without concurrent lung manifestations. Extrapulmonary tuberculosis is rarely contagious, but can cause serious illness and the diagnosis can prove difficult. A standard chest X-ray to reveal tuberculosis is performed on all new immigrants when arriving to Norway. Extrapulmonary tuberculosis is not necessarily detected by this routine.Materials and Methods: 6 Somalian patients, 5 members from one family, a mother and her 4 girls, and a girl from their neighbourhood, were admitted to our hospital in 2003 and 2004, all with symptoms of a chronic infection. There had been no signs of tuberculosis in any of them upon immigration. Basic diagnostic imaging techniques are often insufficient and in addition to plain radiography, special examinations such as bone scintigraphy with 99mTc-methylene diphosphonate, MR imaging, CT and ultrasound were performed.Results:The mother (41) had an abscess in the first sacral vertebra. The first daughter (18) had pulmonary tuberculosis, the second (13) had tuberculous osteomyelitis in 3. and 4. lumbar vertebra. The third (11) had a tuberculous abscess in the right os frontale and the fourth (9) had manifestations in both humeri and both femora. The neighbour

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Poster Presentation

compare the diagnostic value of combined dynamic bone scan / 67Ga scan (DBS/ 67GaS) with MRI in the early phase of VO. Patients and Method. Twenty five patients (14 males and 11 females, aged between 16 and 75 years), suspected of having VO, underwent DBS/67GaS and MRI within 15 days of the onset of symptoms. DBS/ 67GaS was considered as positive for infection, when at least blood pool and metabolic phase were positive in bone scan and 67Ga uptake up-take was equal or greater than that of MDP. Final diagnosis of infection was based on surgical/histological findings (n=5), tissue or blood cultures (n=6) and clinical follow up, for at least one year after response to antibiotic treatment (n=5). In the remaining nine patients symptomatology was eventually attributed to other causes.Results: DBS/ 67GaS and MRI findings

girl had tuberculous abscesses in both calcanei. In only 1 of the 5 cases of bone tuberculosis could this be detected by a standard skeletal X-ray. Bone scintigraphy and MR were equally effective, both detecting all 5 cases. The multifocal disease in the fourth daughter was only detected by bone scintigraphy.Conclusions: Tuberculosis is increasing in Norway, mainly due to immigration. Bone scintigraphy and MR imaging appear to be the the most reliable methods of diagnosing bone tuberculosis.

P727 Possibilities of radionuclide diagnostic in the assessment of gonitis activity V. Zavadovskaya, M. Zorkaltsev, O. Kilina, A. Khodashiskaja, T. Perova; Siberian State Medical University, Tomsk, Russian Federation. The aim: to compare effectiveness of WBC-99mTc-nanocolloid scan and 3-phase bone scan (3FBS) in diagnostics arthritis of different etiology. Material and methods. We studied 60 patients (28 males, 32 females, mean age 38,4±3,6 years) having injured knee joints in rheumatoid (n=44), psoriatic (n=10) and podagric arthritis (n=6). Gonite activity of the 1-st degree was revealed in 14, of the 2-nd degree in 30 and of the 3-rd degree in 16 patients. 3FBS (n=40) was done based upon standard method. WBC-99mTc-nanocolloid scan (n=60) was performed 1 hour after i.v. administration radiotracer. Qualitative and quantitative assessment of the indicator distribution in regions studied was performed. Results and discussion. The 3FBS revealed increased uptaken of the indicator in 58 out of 80 joints studied. The indicator uptake was assessed as to be high in 41 patients and as to be moderate in 17 patients. 22 patients revealed no indicator accumulation. The indicator uptake was assessed as TP and corresponded to the inflammation process in 43 of 58 joints. Radiotracer accumulation in most of patients (n=32) was high and was not depended on the expression of laboratory signs of inflammation (p>0.05). Uptake of the marker was due to degenerative-dystrophic changes in knees in 15 observations (FP). 22 case without indicator accumulation were assessed as TN results. The 3FBS had 96% of sensitivity, 57% of specificity and 79% of diagnostic accuracy. According to WBC-99mTc-nanocolloid scan data, local uptake of the indicator was revealed in 89 of 120 joints. The indicator accumulation was high in 13, moderate in 48 and low in 28 patients. 31 joints did not reveal any increased accumulation of the indicator. The radiotracer accumulation was assessed as TP result in 88 joints. In one patient, accumulation of the indicator was due to secondary inflammation changes in osteoarthrosis and was assessed as FP result. Accumulation of the indicator was absent in 31 patients: 24 were assessed as TN and 7 as FN. Results of the study allowed to reveal correlation between indicator accumulation degree and the expression of clinical and laboratory data of the knee inflammatory changes activity (p<0.05). Sensitivity, specificity and diagnostic accuracy of the method were 93%, 96% and 93% respectively. Conclusion. The 3FBS had high (96%) sensitivity in the revealing inflammation of the joints but because of low (57%) specificity. WBC-99mTc-nanocolloid scan had high (93%) sensitivity and specificity (96%) and gave the possibility to assess inflammation activity degree as well.

P728 Quantification of the in patients with vascular grafts

leukocytes’

scintigraphy

I. Kostadinova, A. Pavlova; Clinical Center of Nuclear Medicine, Medical University, Sofia, Bulgaria. It is not always easy to assess the result of leukocytes (Le) scintigraphy in patients (Pts) with a suspicion for infection in vascular grafts, based only on qualitative criteria. The aim of the investigation was to introduce an objective quantification of the results of Le scintigraphy in Pts with uni- and bilateral bypass. We have examined 24 Pts, for a period of 10 years, with a suspicion for infection - 14 with aortofemoral, 7 with aortobifemoral and 3 with ileofemoral bypass. We have used “in vitro” method for labeling of Le with 99m-Tc-HMPAO and the scans were carried out on 15 and 120 minutes p.i. An “index of accumulation” /IA/ was used in Pts with unilateral grafts for a proof of the infection and for an evaluation of the activity of the process. It was calculated as an activity of the suspected area / background, divided by the activity of the contralateral area / background. As in some of the Pts (2/7) with bilateral bypass, there was a suspicion for infection in both branches, we quantify the results by using a gradient of the index of accumulation (gIA). It was calculated as an activity of the respective branch of the graft / background on 120 minutes, divided by activity of the same branch / backgraund on 15 minutes. In all Pts the results of the Le scintigraphy was proved by surgery, microbiology or following course of disease. The infection was ruled out when IA was below 1,1 (3 Pts), low grade of activity - IA was between 1,1-1,3 (10 Pts) and an active infection - IA was above 1,3 (11 Pts). Normally gIA was bellow 1.0 (between 0,50-0,83) and in cases with infection it was above 1.0 (between 1,03-1,38) in accordance with the activity of the process. We consider that gIA reflect objectively the specific accumulation of Le in respective area and it is especially useful in cases with suspicion for infection in both branches, where IA was not applicable. Using qualitative and quantitative criteria we haven’t found any false positive or negative results (accuracy 100%). In conclusion we could say that quantitative criteria for the evaluation of the results of Le scintigraphy in Pts with vascular grafts increase accuracy, by making interpretation more objective and accurate.

P58 — Monday, October 02, 2006, 2:30 pm - 4:00 pm, Poster Exh.Area

2nd ISRTRD - Special Posters P729 Clinical efficacy of a gamma camera method to calculate therapeutic Iodine-131 activity in hyperthyroidism S. Carmona1, A. Prata1, D. Passos2, J. Portugal2, A. I. Santos1; 1Serviço de Medicina Nuclear - Hospital Garcia de Orta, Almada, Portugal, 2Serviço de Endocrinologia e Diabetes - Hospital Garcia de Orta, Almada, Portugal.

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Aim: To evaluate the clinical efficacy of a gamma camera method to calculate I-131 activity administered in hyperthyroidism therapy.Materials and Methods: We have studied 148 patients [121 females and 27 males- 55,6 years (19-85 years)], all of them with a 2 years follow-up (Group A). From these patients, 125 patients had a 3 years follow-up (Group B). There were three pathological groups: Multinodular Goiter (MNG)-32 patients (pts), Diffuse Goiter (DG)-84 pts and Toxic Adenoma (TA)-32 pts. To determine the I-131 therapeutic activity (TAct), I-131 (740Bq) were administered and the 24h uptake (Up) was determined on a gamma camera, using a standardized method. A thyroid planar image was obtained to determine the thyroid mass (M), based on its area. The TAct was calculated by the formula TAct=((MxSR)/Up)x100, where SR means Specific Radioactivity (3,7MBq/g of thyroid tissue for DG and MNG, and 9,3 MBq/g for TA). The mean therapeutic activities administered were 340MBq (111-593MBq).Results: Group A Between 6 to <12 months after treatment: 30 pts were in hypothyroidism (Hypo); 48 pts were in euthyroidism (Eu) and 70 pts were in hyperthyroidism (Hyper); between 12 to <24 months 31 pts were in Hypo; 58 pts were in Eu and 59 pts were in Hyper. Between 6 to <12 months posttherapy euthyroidism rate (ER) and hypothyroidism rate (HR) were 32% and 20% and on the second year after therapy 38% and 21%, respectively. Analyzing each primary thyroid pathology, on the second year follow up, ER and HR were, respectively: TA(32 pts)-66% and 6%; BMN(32 pts)-43% and 16%; and DG(86 pts)-27% and 29%, showing a significant difference by pathology (p<0,05 - Pearson chi square test). Group B Between 12 to <24 months after treatment the results were: 28(22%)pts were in Hypo, 45(36%)pts were in Eu and 52(42%)pts were in Hyper. Between 24 to <36 months-31(25%)pts were in Hypo, 48(38%)pts were in Eu and 46(37%)pts were in Hyper, showing that a small percentage of patients achieved remission even on the third year after treatment.Conclusions: Iodine-131 therapeutic activities can be easily calculated by a simple gamma camera method, achieving acceptable euthyroidism and hypothyroidism rates. These rates are significantly better for toxic adenoma and worse for diffuse goiter. Hyperthyroidism remission can be achieved even 3 years after the therapy, supporting the idea that a second treatment should be delayed whenever possible.

P730 Change of intrathyroidal kinetics of radioiodine with and without thyreostasis in patients with Graves` disease S. Dunkelmann, H. Künstner, B. Rohde, P. Groth, C. Schümichen; University of Rostock, Clinic of Nuclear Medicine, Rostock, Germany. Purpose: Quantitative evaluation of the thyroidal kinetics of radioiodine in GD under continued thiamazole medication and after discontinuation of thiamazole for 1 - 4 days in order to keep this period as short as possible and to explore underlying mechanisms. Methods: 316 pts. were included in the study. Thiamazole was never applied in collective I (n=89, in collective II (n=44)thiamazole was discontinued 4-15 days, in collectives III (n=57) 3 days, IV (n=38) 2 days and V (n=23) 1 day before radioiodine test. Thiamazole (11.0±7.0 (5-30) mg/day) was continued in collective VI (n=65). Diagnostic and therapeutic radioiodine kinetics were followed for two days by 10 uptake measurements each. Kinetics of radioiodine were defined mathematically by a two-compartment model. Results: In Collectives I-IV (thiamazole never applied or discontinued for at least two days) all uptake curves could be fitted perfectly by a simple in- and output function, in Collective I, the mean square error (mse) was 0.38 (test) and 0.28 (therapy). In Collective VI (thiamazole continued) the energy-dose delivered to the thyroid was lowered by factor 2.15. Radioiodine uptake did not correlate well with the daily thiamazole dose (r=0.2598). Under continued thiamazole medication, all uptake curves were more or less deformed, the mse was elevated to 1.06 and 0.86. A clearly two-peaked uptake curve with two maxima, one very early after 3 hrs and one delayed after 20 hrs and both on a low level, was seen in 45 %, a moderately two-peaked uptake curve also on a low level in the remaining 55 %. This two-peaked uptake, not recognized by a conventional radioiodine test, is explained by a coexistance of follicles with totally-blocked hormone synthesis but still active sodium iodide symporter and those follicles with still intact hormone synthesis. Radioiodine uptake in follicles with intact hormone synthesis contributed to >98% of the energy dose delivered to the thyroid. The uptake values recovered one day after discontinuation, but residual deformation was still seen (mse 0.78), whereas two days after discontinuation, the uptake curve was completely restored (mse 0.31). Conclusion: Efficacy of radioiodine therapy in GD is reduced by continued thiamazole medication mainly by a lower uptake and shorter half-life of radioiodine and by a heterogeneous radioiodine and energy-dose distribution in the thyroid, indirectly visualized by kinetic data. Two-day discontinuation of thiamazole is sufficient to restore the efficacy of radioiodine. This statement is valid for thiamazole and carbimazole but not for propylthiouracil.

P731 131

A new method for calculating the optimal I activity for Graves’ disease therapy based on the reduction of thyroid mass: preliminary results of a prospective, randomized study. A. C. Traino1, M. Grosso1, F. Di Martino1, B. Alberti1, G. Mariani2, M. Lazzeri1; 1Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy, 2Azienda Ospedaliero-Universitaria Pisana e Università di Pisa, Pisa, Italy. Aim: The use of 131-I in Graves’ disease therapy has a long history, but there is no consensus regarding the most appropriate dosimetric approach. Traditionally the amount of 131-I is decided based on one of two different modalities: 1. the administration of a fixed radioiodine activity A0(MBq) (usually 555 MBq);2. the administration of an activity individually calculated based on a fixed value of target absorbed dose DT(Gy). Recently an empirical relationship between posttherapeutic thyroid volume and therapy outcome has been reported. This suggests the possibility to decide the optimal 131-I activity based on the desired therapy-induced reduction of thyroid volume.Materials and Methods: A model for the “optimal” final thyroid mass calculation is being published (Traino et al, Nucl Med Comm, in press), based on measurements of thyroid volume performed in 40 patients. Following this model the optimal thyroid final mass mfin can be individually calculated using an equation involving the basal mass and maximum thyroid uptake. The final thyroid mass can be correlated to the administering 131-I activity using another predictive model previously published (Traino et al. Phys Med Biol 2005; 50:2181-2191), thus allowing to calculate the therapeutic activity based on the desired final mass of the gland. To test

P732 Is one whole body retention measurement sufficient for the assessment of the I-131 blood dose in patients with differentiated thyroid carcinoma? M. Lassmann, H. Hänscheid, M. Luster, C. Reiners; Nuclear Medicine, Wuerzburg, Germany.

Department of

Aim: Limitation of blood dose to 2 Gy or less is an established method to reduce the potential toxicity of radioiodine treatment of differentiated thyroid cancer (DTC). The exact assessment of the blood dose requires a complete set of measurements of the blood and whole body compartments in order to calculate residence times. In this work, a simple method of assessing the blood dose using only one whole body retention measurement is introduced and compared to the conventional method.Methods: Iodine biokinetics in whole body and blood after administration of 3.7 GBq I-131 for remnant ablation was measured as part of in an international multicenter trial with 63 DTC patients and resulting blood doses were calculated. Using this data set a simplified dosimetry algorithm was implemented and tested which allows determining the blood dose from a single whole body retention measurement 24h or 48h after administration of I131. In order to validate the simplified approach and extend it for diagnostic studies the method was also retrospectively applied to the data of a diagnostic trial (74 MBq I-131, n=20).Results: The mean blood dose was 0.121±0.029 mGy/MBq (range: 0.073-0.187 mGy/MBq) in the diagnostic setting and 0.135±0.054 mGy/MBq (range: 0.064-0.353 mGy/MBq) in the therapy trial. For both study settings the results of the simplified algorithm were in good agreement with those determined with the exact method. Comparing the doses calculated from the 24h whole body retention to the values based on the completely measured biokinetics we found a mean deviation of 16% (min. -37%, max. +49%). The mean error was reduced to 13% (min. -24%, max. +39%) when using the 48h whole body retention. The corresponding results for the therapeutic assessment were 11% (min. -37%, max. +27%) for the 24h retention value and 11% (min. -22%, max. +69%) for the 48h retention. The risk of underestimating the dose is reduced when the 48h value is used.Conclusions: For patients with DTC a simple, fast and remarkably reliable blood dose assessment can be performed using only one measurement of the whole body retention. The method is adequate to routinely estimate the blood dose after radioiodine therapy. The accuracy is also sufficient in a pretherapeutic dose assessment if the predicted therapeutic blood dose should not exceed the safety level of 2 Gy. It should be noted, however, that the method of blood dose determination is not validated for patients with large remnants or lesions.

P733 A target-mass reduction based model for personal dosimetry 131 calculation in I therapy of thyroid cancer A. C. Traino, F. Di Martino; Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy. Aim: 131-I therapy is used in the treatment of differentiated thyroid cancer both to ablate the post-surgical thyroid remnant and to treat recurrent or metastatic cancer. Until now the better method for the calculation of the therapeutic activity is controversial: the most used method is the administration of a fixed radioiodine activity (1110-3700 MBq or more); an alternative is the administration of an activity individually calculated on the basis of an optimal fixed value of target absorbed dose (usually 300 Gy). Both these methods are based on statistical considerations. None of these two approaches is based on a theoretical model and for this reason the debate on the optimization of 131I therapy of thyroid cancer has a very weak grounding.Materials and Methods: Recently a model which relates the 131-I administering activity to the thyroid mass reduction due to radioiodine therapy has been published for Graves' disease patients (Traino et al. Phys Med Biol 2005; 50:2181-2191). This model is based on the radiobiological linear-quadratic (LQ) equation for the thyroid irradiated cells surviving. In this study its application to the remnant/metastasis 131-I ablation is discussed and consequently a mathematical equation for remnant/metastasis optimal absorbed dose calculation is presented, based on the desired reduction of the volume of the target (remnant or metastasis).Results: The mathematical equation obtained to describe the model presented is obtained matching the MIRD equation with the LQ model. It depends on macroscopical parameters (basal mass of the target, effective half-life of 131-I in the target, time to maximum uptake, maximum uptake in the target) thus it allows to calculate predictively the optimal ablative activity.Conclusions: A new model for the individualized dosimetry in thyroid cancer post surgical remnant/metastasis ablation is presented and discussed. It is based on theoretical instead on statistical considerations. Following this model the effectiveness of fixed activity administration and calculation of the activity based on a fixed target absorbed dose can be explained in some special cases.

P734 Evaluation of the Accuracy to be Expected in an Absorbed Dose Calculation based on Whole-body Scintillation Camera Imaging L. Jonsson, M. Ljungberg, S. Strand; Medical Radiation Physics, Lund University, Lund, Sweden.

Aim: An activity determination based on scintillation camera images and conjugate-view quantification may lead to inaccurate results due to contribution from scattered photons emitted from adjacent organs and from activity in overlapping tissues. In a previous study, biodistribution data obtained in rats were used to simulate scintillation camera images where the Zubal phantom was used. The organ activity was then evaluated from the simulated images. The aim of this study was to extend the study by calculate the absorbed dose using Zubal phantom-specific S factors (Gy/MBq h) in combination with residence times calculated from simulated scintillation camera images and to compare the absorbed doses with those calculated from the actual time activity distribution.Materials and Methods: Monte Carlo simulations of scintillation camera imaging based on an activity distribution obtained in the animal study, were performed using the SIMIND code. The Triple-Energy Window (TEW) method was made for scatter correction and a phantom-specific transmission factor image for the attenuation correction. Images were simulated for both 99Tcm and 131I. From a regions-of-interest (ROI) analysis the activity was calculated using the conjugate-view method together with attenuation and scatter corrections. Residence times were calculated both for the data obtained from the ROIs and from the known activity distribution data defined in the simulations. The S factors specific for this voxel-based phantom were calculated using a Monte Carlo program based on the EGS4 code and from these the absorbed doses in major organs were calculated.Results: The residence times as been calculated from the simulated images were overestimated for several organs because of contribution from overlapping tissue activity and from scatter contribution. For example, the residence time for the kidneys was overestimated by a factor of 10 for 99Tcm and 12 for 131I. Since activity in surrounding tissues also contribute to the absorbed dose to a particular organ, the overestimation in the calculated absorbed dose was reduced to 5 and 7 times, respectively. A comparison with the absorbed doses calculated with the OLINDA computer program using the standard S factors will be made.Conclusions: We present a method to investigate the accuracy in the activity quantification part of an absorbed dose calculation where the use of patient-specific S factors and its influence on the absorbed dose also is demonstrated.

P735 Dosimetric characterization of radionuclides for systemic tumour therapy: influence of particle range, photon emission, and subcellular distribution H. Uusijärvi1, P. Bernhardt1, T. Ericsson2, E. Forssell-Aronsson1; 1 Department of Radiation Physics, Göteborg University, Göteborg, Sweden, 2 Department of Mathematical Sciences, Chalmers University of Technology, Göteborg, Sweden. Aim: Various radionuclides have been proposed for systemic tumour therapy. However, in most dosimetric analyses of proposed radionuclides the charged particles are taken into consideration while the potential photons are ignored. The photons will cause undesirable irradiation of normal tissue, and increase the probability of toxicity in, for example, the bone marrow. The aim of this study was to investigate the dosimetric properties according to particle range, photon emission and subcellular radionuclide distribution, of a selection of radionuclides used or proposed for radionuclide therapy, and to investigate the possibility of dividing radionuclides into groups according to their dosimetric properties. Materials and methods: The absorbed dose rate to the tumours divided by the absorbed dose rate to the normal tissue (TND) was estimated for different tumour sizes in a mathematical model of the human body. The body was simulated as a 70-kg ellipsoid and the tumours as spheres of different sizes (1 ng - 100 g). The radionuclides were either assumed to be uniformly distributed throughout the entire tumour and normal tissue, or located in the nucleus or the cytoplasm of the tumour cells and on the cell membrane of the normal cells. Fifty-nine radionuclides were studied. The tumour and normal tissue were assumed to be of water density. The activity concentration ratio between the tumour and normal tissue was assumed to be 25. Results: The radionuclides emitting low-energy electrons combined with low photon contribution, and the alpha emitters showed high TND values for most tumour sizes. Electrons with higher energy gave reduced TND values for small tumours, while a higher photon contribution reduced the TND values for large tumours. Radionuclides with high photon contributions showed low TND value for all tumour sizes studied. The radionuclides studied could be divided into four main groups, according to their dosimetric properties: 1) electron emitters with no subcellular effect on the TND values (e.g.33P, 177Lu, 131I, and 90Y); 2) Auger electron emitters with subcellular effects on the TND values (e.g.103mRh, 201Tl, and 125I); 3) photon emitters with low TND values and small subcellular effect on the TND values (e.g. 99m Tc); and 4) the alpha emitters (e.g. 211At). Conclusions: It was possible to divide the radionuclides into different groups according to their dosimetric properties, i.e. their TND values and the dependence of radionuclide distribution on the TND values. This dosimetric characterization of radionuclides may be valuable in choosing the appropriate radionuclides for specific therapeutic applications.

P736 211

Dosimetry of At in humans estimated from the biodistribution in animals

211

At

U. Lindencrona, T. Bäck, E. Forssell-Aronsson; Department of Radiation Physics, Göteborg, Sweden. Aim: To be able to optimize the therapy of malignancies with 211At-labelled compounds, such as antibodies, an estimation of the absorbed dose of possible released free 211At to the normal tissues is necessary. Furthermore, in the evaluation of the potential use of free 211At in the treatment of anaplastic thyroid carcinoma, the knowledge of the 211At biokinetic in human is of highest importance. Since no biokinetic data of 211At has been obtained in man, we estimated the absorbed dose to different organs and tissues in man based on new and previously presented biokinetic data in rat and mouse.Materials and Methods: Athymic nude mice were injected intravenously with 0.4 MBq 211At and 0.4 MBq 99mTcO4- simultaneously. The mice were sacrificed 0.5-24 hours after injection, and tissues and organs were immediately collected and the activity concentration measured. The absorbed dose of 211At to different tissues in man and the effective dose to humans were estimated based on extrapolation of the biodistribution data obtained from the rat and mouse.Results: The biodistribution of 211At in mice obtained in the present study correspond in general well with the results from the previous studies. Similar

S371

Poster Presentation

this new modality, the Graves’ disease patients treated in our Nuclear Medicine Department were randomly divided into three groups: 1. Group 1 (GR1): the 131-I activity has been calculated based on a thyroid absorbed dose of 100 Gy;2. Group 2 (GR2): the 131-I activity has been calculated based on a thyroid absorbed dose of 400 Gy;3. Group 3 (GR3): the 131-I activity has been calculated based on the “optimal” thyroid final mass mfin.Results: Until now we have the one-year follow-up of 16 patients of GR1; 12 patients of GR2 and 25 patients of GR3. 9/16 (0.56) patients of GR1, 11/12 (0.92) patients of GR2 and 24/25 (0.96) patients of GR3 were cured (i.e. they became eu or hypothyroid). Statistically there is a difference (p<0.01) between the percentage of patients cured in GR1 and GR3 and no difference between GR2 and GR3 (p>0.05). The average thyroid absorbed dose is 402±22 Gy for GR2 and 260±80 Gy for GR3 (p<0.001); the average administered activity is 640±204 MBq for GR2 and 379±140 MBq for GR3 (p<0.001).Conclusions: If confirmed, these data demonstrate that the thyroid-mass reduction based method allows to individually optimize the 131-I therapy for Graves’ disease.

concentrations of 99mTc and 211At were observed in the kidneys, liver, muscle, skeleton, bone marrow, and fat, while there was a higher concentration of 99mTc in blood, and a higher concentration of 211At in the lungs and spleen. The highest estimated absorbed dose per unit activity administered from both species to man were obtained for the thyroid and stomach from both species together with the pituitary from rat and the salivary glands from mouse, all being NIS-expressing tissues. However, the metabolism of 211At is quite different from that of iodide, at least in animals, and the iodide kinetic models given by ICRP cannot be applied to 211At in man. The estimated effective dose to man differed a factor of about two depending on species used as base for the calculations (93 and 190 mSv/MBq for rat and mouse, respectively). Conclusions: Translation of biokinetic data from laboratory animals to man is complex for reasons which include the differences in rates of distribution and metabolism of the radionuclide and in the mass of an organ relative to the body mass. Differences in expression of e.g. NIS, hormones and their receptors between different species will further complicate such translations.

P737 Biodistribution of the novel alpha-emitting 227 radioimmunoconjugate Th -DOTA-p-benzyl -rituximab in mice with CD20 positive human B-lymphoma xenograft J. Dahle1, J. Borrebæk2, K. B. Melhus1, Ø. S. Bruland3, R. H. Larsen2; 1 Institute for Cancer Research, The Norwegian Radium Hospital, Oslo, Norway, 2Algeta ASA, Oslo, Norway, 3Department of Oncology, The Norwegian Radium Hospital, Oslo, Norway. Murine monoclonal antibodies (mAb) conjugated with the beta-emitters 131I and 90Y is currently used for therapy against CD20 positive B-cell lymphoma. We have conjugated a humanized CD20 mAb (rituximab) with the alpha-emitting nuclide Thorium-227 using the bifunctional chelator p-SCN-benzyl-DOTA. Alpha particles are more cytotoxic than ȕ-particles and have a range of 40-100 µm, while beta particles have ranges of typically a mm or more. Thus, in some settings 227Th -DOTA-p-benzyl-rituximab may have an increased effect on cancer cells and induce less normal tissue damage compared with the ȕ-emitting conjugates. The half-life of 227Th is at a favourable 18.7 days and can be produced with good yield and a relevant purity from a generator system involving the parent nuclide 227Ac (half-life of 21.8 years). 227Ac can be produced by thermal neutron irradiation of 226Ra.Methods: Uptake of 227Th-DOTA-p-benzylrituximab in tumor and normal organs were measured, using the 236 keV gamma peak of 227Th and the 154 keV peak of 223Ra, with a germanium detector. The absorbed dose to organs was calculated assuming the dose contributions coming from alpha particle emissions with a mean energy of 5.9 MeV for 227Th and a mean energy of 26.4 MeV for 223Ra and daughters. It was assumed that the radium daughters deposited their energy in the same tissue as radium itself.Results: The uptake of 227Th-DOTA-p-benzyl-rituximab reached a maximum at 1 day after injection and decreased linearly with an effective half-life of 9.5 days. The cumulated activity of 227 Th-DOTA-p-benzyl-rituximab was more than 5.9 times higher in tumor than in normal organs, except for femur, skull and liver, where the cumulated activity in tumor was 2.7, 4.4 and 3.9 times higher, respectively. The higher uptake in bone and in liver than in the other organs can be explained by redistribution of the daughter nuclide 223Ra to bone and clearance thorough the biliary system, respectively. Injection of 100 kBq/kg 227Th-DOTA-p-benzyl-rituximab resulted in an absorbed dose of 1 Gy in tumor and 0.25 Gy in liver. Also, the bone surfaces received a significant absorbed radiation dose, mainly from the 223Ra daughter series. In conclusion, the data suggest that 227Th-DOTA-p-benzyl-rituximab yields promising tumor to non-tumor dose ratios. Among non-target organs the bone surfaces receives the highest dose.

Methods: Ninety-three hyperthyroid patients (12 with Graves’ disease and 81 with autonomously functioning nodules) were studied and 137 thyroidal structures were evaluated. The mean time interval between dosimetry and therapy was 20± 10d. Uptake values were measured at 2, 4, 24, 48, and 120h during dosimetry and at 2, 4, 24, 48, 96, and 168h during therapy. The value 0.125d-1 was chosen in the fixed-Ȝ eff method. The planned doses to the target ranged from 120 to 250 Gy depending on the type and severity of hyperthyroidism.Results: The following significant correlations between therapeutic and dosimetric parameters were found: U0ther=0.87U0dos (r=0.97 p<0.01), Ȝ effther=1.01Ȝ effdos (r=0.85 p<0.01) and Destimated=0.85Dplanned (r=0.90 p<0.01). The percent difference between U0ther and U0dos ranged from -44 to 32% and between Ȝ effther and Ȝ effdos from -32 to 48%. U0ther was lower than U0dos in 74% of cases: this can be explained by the self-stunning effect of 131I therapeutic activity that produced a dose of about 20 Gy with a maximum dose rate of 0.6 Gy/h over the initial 24-48h. The differences, ǻ D, between the estimated and the planned doses ranged from -42% (-87Gy) to 32% (59Gy); in 73% of cases the difference was within ± 35Gy. Greater discrepancies were found with the fixed-Ȝ eff method in which ǻ D ranged from -69 to 95% (-202 to 88Gy, respectively). In hyperthyroid patients, the 5 uptake value dosimetric method is able to predict with a good agreement the radioiodine kinetics and the dose after the therapeutic administration in about 73% of the analyzed thyroid structures. The fixed-Ȝ eff method is less reliable.

P740 186

Tumour dosimetry on SPECT Re-HEDP scans; variations in the results due to the reconstruction used. A. Divoli1, G. Bloch1, S. Chittenden2, A. Malaroda1, G. Flux2; 1Institute of cancer research, Sutton, United Kingdom, 2Royal Marsden Hospital Foundation Trust, Sutton, United Kingdom. Aim: The estimation of the absorbed dose delivered to cancerous and normal tissues is of extreme importance in Targeted Radionuclide Therapy. It is generally accepted that iterative reconstruction methods result in better quality images than analytical ones and generally are used for dosimetric purposes. The aim of this work was to estimate absorbed dose (AD) delivered to bone cancerous sites using the standard MIRD formalism, in order to examine variations and reproducibility due to the reconstruction. (OSEM versus FBP).Methods: Sequential SPECT data obtained with a dual headed gamma camera were analysed on 7 patients with multi side bone metastasis treated with 186Re-HEDP. The data were reconstructed using FBP and OSEM. Correction methods for scatter and attenuation were kept identical. Same calibration data and thresholding techniques were used to obtain quantification. The study was carried out in chest (spinal) and pelvic lesions. Maximum and mean values of counts in the identified lesions were used to obtain AD after multiplication of the appropriate S factor. In order to investigate the effect of the statistics to the dosimetric calculations for a subset of patients, AD were calculated from single head (SH) and combined dual head data (DH) for each lesion.Results: For comparison the AD based upon the maximum and the mean voxel count were calculated. The resulting mean values were ADmax: 60 Gy (ı = 30 Gy) and 33 Gy (ı = 15 Gy) for OSEM and FBP respectively, and ADmean: 26 Gy (ı = 12 Gy) and 17 Gy (ı = 7 Gy) with OSEM and FBP respectively. From preliminary results the ratio of the AD calculated from SH and DH data either based on the mean or the max value was ~ 1.6 and ~ 1.1 for OSEM and FBP respectively indicating that the statistics play a greater role in the iterative methods.Conclusions: Using the same methodology to estimate tumor AD the choice of the algorithm can result in differences over 50%. Most importantly OSEM might not be the right choice when low statistic data is available. The need for standardization of the methodology used for the calculations is emphasized by this work especially when comparisons between patients, and different centres are of interest.

P738 Ga-68-DOTATOC molecular modelling in carcinoid tumors.

P741

M. Hofmann1, T. Weitzel1, S. Weidner1, F. Corminboeuf1, H. Meacke2, T. Krause1; 1Clinic of Nuclear Medicine, Molecular Imaging and Therapy Group (MIT-Bern,CH), Inselspital, Bern, Switzerland, 2Div. of Radiological Chemistry, University Hospital Basel, Basel, Switzerland.

Multimodality imaging of therapeutic holmium-loaded poly(Llactic acid) microspheres: Sensitivity and detection limits of MRI, CT, and SPECT

Aim: Using Ga-68 somatostatin receptor binding peptides for PET/CT has recently gained interest in clinical application. In this study the feasibility of a simple 2 compartment modelling was evaluated.Methods: 12 patients (7 males and 5 females, age= 64-42y) were given a diagnostic dose of 50-250MBq of somatostatin receptor ligand [68Ga]-DOTATOC as bolus injection i.v. and scanned dynamically for 0-60min p.i. over the upper abdomen (region with liver metastases). The input function was measured by arterial blood sampling and a 2 compartment model was fitted using the PMOD software.Results: The suggested 2 compartment model with 4 rate constants (k1-k4) did fit the time activity curves best (p<0.05). K1 was found to range between 0.28-42, and k2 0.02-0.04, k3 0.03-0,06, k4 <0.01. The fractional blood volume in the liver tumors ranged from 0.32-0.28.This fitted well with the hypotheses of near instantaneous binding of the ligand to the receptor (k1) and with a low dissociation of the ligand (k2) and a by aprox. 10x slower internalisation of the receptor ligand complex (k4). The k4 was found to be very low.Conclusions: The modelling of the receptor binding of Ga-68-DOTATOC by a 2 compartment model is feasible. It enables in principle a parametric imaging of receptor internalisation (k3), which is a crucial step in the “internalisation trapping”, which is of most interest especially in radiopeptide therapy.

P739 Agreement between two dosimetric methods and radioiodine therapy in hyperthyroid patients C. Canzi, E. Reschini, F. Zito, F. Voltini, P. Gerundini; Fondazione IRCCS Ospedale Maggiore, Milan, Italy. Objectives: The aim of this study was to verify the capability of a MIRD formula based dosimetric method to predict radioiodine kinetics (fraction of administered iodine transferred to the thyroid, U0, and effective clearance rate, Ȝ eff) and absorbed dose after oral therapeutic 131I administration. The method is based on 123I i.v. administration and 5 subsequent gamma camera measured uptake values determined separately on different structures within the thyroid. Another dosimetric method based on only the 123I 24-h uptake and a fixed Ȝ eff value was also considered.

S372

P. R. Seevinck1, J. H. Seppenwoolde1, T. C. de Wit2, J. F. W. Nijsen2, F. J. Beekman2, A. D. van het Schip2, C. J. G. Bakker1; 1Image Sciences Institute, University Medical Center, Utrecht, The Netherlands, 2Department of Nuclear Medicine, University Medical Center, Utrecht, The Netherlands. Introduction and aim Selective intra-arterial radionuclide therapy (SIRT) with neutronactivated holmium-loaded poly(L-lactic acid) microspheres (HoMS) may become a promising therapy for hepatic malignancies. Ho-166 emits ȕ-particles suitable for SIRT and photons suitable for SPECT imaging. Since holmium is paramagnetic and has a high X-ray absorption coefficient, it can also be detected by MRI and CT. The aim of this in-vitro study was to assess the potential of HoMS as a multimodal contrast agent. Materials & Methods HoMS with a size distribution of 20-50 µm, holmium content of 17 % by weight and activated fraction of 1.5 ppm was used. Phantom experiments of a HoMS dilution series were conducted using straightforward clinical scan protocols under signal-known-exactly background-known-exactly conditions. The sensitivity and minimal detectable concentration in a homogeneous background were determined on clinical CT, MRI and SPECT scanners. Imaging parameters: For MRI a typical T2*-weighted sequence for detecting T2* modifying agents was used on a 1.5 T MRI scanner. CT scans were made at three different X-ray tube settings of 80, 120 and 140 kVp at 267mAs. A soft tissue reconstruction filter was used. SPECT images were acquired using settings dedicated to Ho-166. Data analysis: Data analysis was performed on a VOI (area = 3.5 cm2, slice thickness = 1cm). The sensitivity of each imaging modality was expressed as the signal change as a function of the HoMS concentration (dS/d[HoMS]). The minimal detectable concentration was determined using a one-sided t-test (95% confidence). Results Table 1 shows the sensitivity to HoMS and the minimal detectable HoMS concentration for MRI, CT, and SPECT. Despite the low activated fraction, SPECT shows the highest sensitivity and the lowest detection limit, followed by MRI and CT, respectively. The sensitivity of CT shows an inverse relation with X-ray tube voltage. The temporal and spatial resolution are the highest for CT, followed by MRI and SPECT.

Modality

MRI CT,

80

keV CT,

120

keV CT,

140

keV SPECT 1

Pixel

size, ROI,

Imaging

Sensitivity1,

Minimal

(mm)

(pix.)

time

[dS.ml.mg-1]

concentration1, [mg.ml-1]

1.33x1.33

200

69 s

0.68x0.68

760

2.8 s

0.68x0.68

760

2.8 s

0.68x0.68

760

2.8 s

4.72x4.72

16

24 min

92.6 ± 3.2 s1

•ml•mg-1

7.9

±

0.1

HU•ml•mg-1 6.7

±

0.1

HU•ml•mg-1 5.9

±

0.1

HU•ml•mg-1 1435.3

±

au•ml•mg-1

11.6

detectable

0.0055

0.095

0.057

0.055

0.0054

Valid for an activated fraction of 1.5 ppm Ho-166 using standard clinical scan protocols.

Discussion and conclusions Our study clearly indicates the potential of HoMS as a multimodal diagnostic agent. Caution should be exercised, however, in interpreting the results presented in table 1. These results relate to a specific task, specific agent, specific equipment, and specific scan protocols. The sensitivity of SPECT, for instance, strongly depends on the activated fraction, imaging time, voxel size and reconstruction parameters. Likewise, the detection limits will show a strong dependence on the experimental conditions (background homogeneity) and hardware (e.g., B0 and RF coils in MRI) that determine the noise level.

P742 Implementing dosimetry in Gate: beta dose point kernels validation with Geant4.8 l. Ferrer1, A. Lisbona1, N. Chouin2, A. bitar2, M. Bardies2; 1Rene Gauducheau Cancer center, St Herblain, France, 2Inserm U601, Nantes, France. Introduction:GATE (OpenGate collaboration) is a recent Monte Carlo code used in Nuclear Medicine (NM) mainly for imaging and detector design purposes. Gate is based on GEANT4 (CERN), a Monte-Carlo simulation toolkit. GEANT4 derived codes have been evaluated to give dosimetry of external beam irradiation, but to our knowledge none have been used in the context of NM dosimetry. Our goal is to implement dosimetry within Gate, i.e. combining the excellent potential of Gate for imaging modelling with Geant dosimetric capabilities. The latest release of GEANT4 completely revised the electron multiple scattering propagation algorithm. In this work we calculated dose point kernels (DPK) for mono energetic electrons and beta radioactive sources such as iodine-131. We then compared our results with published data obtained with other MC codes.Materials and Methods:GEANT4.8.0 & CLHEP 1.9.2.2 libraries were compiled and linked with gcc4.0.1. DPKs correspond to energy deposited at a distance from isotropic point sources in water equivalent spherical shells. The Geant4 standard transportation model is considered to be valid for energies down to 10 keV. However, other optional models are available for energies below this limit. We calculated DPKs for 0.01, 0.05, 0.1, 1 and 3 MeV mono energetic electron sources for the various models proposed in Geant4. We compared the results obtained with DPK calculated by Berger. To facilitate comparison, all calculated dose distributions were scaled to the corresponding RCSDA, as given by the ESTAR NIST web database. RCSDA, called the continuous slowing down approximation range, reflects the distance travelled by electrons of a given energy down to 10 eV.Results: Some Geant4 parameters (i.e. Stepmax), or the shell thickness had to be adjusted in order to achieve good agreement for energies below 1 MeV. For all energies except 10 keV, most of the relative differences between simulated and already published DPKs were less than 6.7 %. The relative differences increased at the end of the trajectories for very small DPK values. For 10 keV, the relative differences are more than 280%. This problem is being underinvestigation. Convolution of DPKs with beta emitting radionuclide spectra is currently under way.Conclusions: This preliminary step allows us to consider the integration of Geant4 dosimetric capabilities within the Gate framework, and thus to address both the imaging and dosimetric aspects of NM modeling with the same Monte Carlo code.

P743 Assessment of radiation doses at haemophiliacs treated with 186 radiosynoviorthesis with Re colloid M. Grmek, M. Milcinski, J. Fettich, J. Brecelj; University Medical Centre, Ljubljana, Slovenia. Aim: The aim of our study was to asses the radiation dose in haemophiliacs after radiosynoviorthesis (RS) with 186Re colloid.Materials and Methods: 12 haemophiliacs, in whom RS with 186Re colloid was performed between January 2004 and December 2005 for the treatment of haemophilic joint disease, were included in the research. Altogether 14 treatments were done. 186Re colloid, 75 MBq was used for RS of elbow joints (9 treatments) and ankle joints (3 treatments), and 110 MBq for RS of shoulder joints (2 treatments). After application of the radiotherapeutical, the joint was cautiously moved and after that the extremity was immobilized in a plaster splint for four days. Scintigrams of treated joint and drainage lymph nodes were performed 1, 6 and 24 hours, 3 and 7 days after radiosynoviorthesis. Immediately after each scintigraphy, measurement on the whole body counter with the treated joint covered with lead

was done. The cumulative activity of 186Re in the body was calculated. When the activity was seen in lymph nodes on the scintigram, it was subtracted from the activity measured on the whole body counter. The distribution of the activity in the body was determined according to the values that ICRP Publication 53 proposes for small colloids - 70% of the activity in liver, 15% in red marrow, 10% in spleen and 5% in remaining tissues. Internal dose calculation was done by computer program OLINDA/EXM. Constant distance of 1m between ankle joint and body organs and 0.33m between elbow or shoulder joint and body organs was used when calculating gamma radiation contribution to the effective dose.Results: The organs that received the highest doses as a consequence of body retention of 186Re ware spleen 26.0±10.7 mGy, liver 17.6±7.2 mGy and red marrow 3.0±0.8 mGy. The effective dose was 1.9±0.8 mSv (from 0.8 to 3.7 mSv). In 4 of 14 treatments drainage lymph nodes were detected. The average dose that lymph node has received was 14.7±1.9 Gy. The contribution of gamma radiation to the effective dose was: less than 0.1 in RS of ankle joint, 0.4 in elbow and 0.6 mSv in shoulder joint treatment.Conclusions: The effective dose that haemophiliacs receive at RS with 186Re colloid is negligible; the doses to the most exposed organs are also low. If the 186Re is retained in the drainage lymph nodes, the effective dose is also very low but the dose to the lymph node is high.

P744 Voxelwise dosimetry of intracranial brachytherapy with radiolabelled Substance P using SPECT/CT S. Kneifel1, J. Müller-Brand1, A. Merlo2; 1Universitätsklinik und -institut für Nuklearmedizin, Basel, Switzerland, 2Universitätsklinik für Neurochirurgie, Basel, Switzerland. Aim Exact anatomic localization of dose distribution is crucial for an adequate pretherapeutic planning in interstital brachytherapies. Without hybrid devices, this is a tedious procedure requiring coinjection protocols with their well-known uncertainties. The aim of this study is to establish a SPECT/CT based dosimetry model for interstitial brachytherapy with radiolabelled NK1-binding modified Substance P (MSP). Methods In 9 patients harbouring malignant glioma (5m, 4f, age range 33 - 64) 38 dosimetric procedures were performed (12 pretherapeutic test injections using 111In-MSP and 26 therapeutic injections with 90Y-MSP). For each procedure, 4 SPECT/CT scans were acquired (0, 4, 24 and 28 hours p.i.). Doses were calculated on a voxelby-voxel basis using a monoexponential decay model. The peak doses were compared to the doses computed in a former study; additionally, the doses calculated at test injection were compared to the doses calculated at therapy time. Results 33 of 38 procedures were evaluable; the other five procedures could not be completed due to technical or patient-specific reasons. The mean peak dose was 156 +/- 40 mGy/MBq in this study, compared to 152 +/- 26 mGy/MBq in a former study using co-injection protocols for localization. Pre- and posttherapeutic doses showed a good correlation (r2 = 0.82). Conclusions SPECT/CT-based dosimetry yields reproducible results, which are comparable to those using non-hybrid imaging protocols. It greatly facilitates the evaluation procedure, since a tedious and time-consuming manual realignment is no longer necessary. However, the computed doses will not be comparable to those known from external beam radiotherapy due to different exposure times. Further studies have to reveal the correlation between doses and clinical outcome.

P745 First comparative dosimetric results after peptide receptor radionuclide therapy (PRRT) using Lu-177 DOTA-NOC and Lu-177 DOTA-TATE C. Wehrmann, S. Senftleben, R. P. Baum; Zentralklinik Bad Berka, Bad Berka, Germany. Aim: DOTA-NOC shows the highest affinity to the somatostatin receptors (sstr) 3 and 5 and a very high affinity to sstr 2. We compared uptake, half-life (kinetics) and mean absorbed organ and tumor doses of Lu-177 DOTA-NOC and Lu-177 DOTA-TATE.Methods: 78 patients with neuroendocrine tumors with high sstr expression (verified by Ga-68 DOTA-NOC PET/CT) were studied. 73 patients (25m and 34f; aged 61±10a) were treated with 2.5-7.4 GBq Lu-177 DOTATATE and 5 patients (1m and 4f, aged 63±10a) with 4-7.4 GBq Lu-177 DOTA-NOC. Wholebody scans were performed after 0.5h, 3h, 24h, 48h, 72h and 96h p.i. Blood samples from 23 patients were obtained after therapy. By means of geometric mean and after background correction, ROI results were used to calculate the estimated absorbed organ and tumor doses (OLINDA software).Results: Lu-177 DOTA-NOC showed a higher uptake as compared to Lu177 DOTA-TATE (=100%): for whole-body about 44% and in normal tissue 19%, in the spleen 4% and in the kidneys 5%. The tumor uptake was about 8% higher for DOTA-NOC. The effective half-life for whole-body was comparable for both peptides (t1/2a NOC 3.2h vs. TATE 2.6h and t1/2b NOC 58h vs. TATE 57h). In normal tissue, t1/2a was similar (NOC 3.0h; TATE 2.8h) but the t1/2b was longer for DOTA-TATE (NOC 43.1h; TATE 48.8h). t1/2b was longer for DOTA-NOC in the spleen (NOC 77h; TATE 72h) and in the kidney (NOC 78.1h; TATE 65.7h), but the mean absorbed dose in the kidney (5 Sv) and spleen (6 Sv) was similar. In the tumor, the t1/2b was nearly identical for both peptides (NOC 79h; TATE 77.2h). For DOTA-TATE the whole-body dose was lower (0.26 Sv) as compared to DOTA-NOC (0.41 Sv). The estimated mean absorbed tumor doses were 64+/-98 Sv for DOTA-TATE and 50+/-42 Sv for DOTA-NOC (significant by paired t-test). The red marrow dose was about 0.2 Sv.Conclusions: Our first results confirm that the higher in vitro affinity of DOTA-NOC leads to a higher uptake in normal tissues and therefore increases the whole-body dose. However, Lu-177 DOTA-TATE was superior to Lu-177 DOTA-NOC concerning the obtained tumor dose.

P746 Comparison of the dosimetry of Ga-68/67-DOTATOC using volume of interest and region of interest methods with OLINDA/EXM software. F. Corminboeuf1, S. Weidner1, T. Weitzel1, A. R. Boerner2, T. Krause1, M. Hofmann1; 1Clinic of Nuclear Medicine, Molecular Imaging and Therapy Group (MIT-Bern, CH), Inselspital, Bern, Switzerland, 2Clinic of Nuclear Medicine, Medical School Hannover, Hannover, Germany.

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Poster Presentation

Table 1: Summary of relevant parameters and results for MRI, CT and SPECT.

Aim: Common dosimetry protocols prior radiopeptide therapy (RPT) use a tracer dose of the radio-peptide conjugate to determine its local uptake and its biodistribution by conventional gamma imaging. As a more appropriate approach positron tracers for PET/CT can be applied to enable accurate quantification of organ activity uptake (PET) and organ volume (CT). Therefore we used Ga-68/67-labeled peptides (DOTATOC) PET/CT vs planar scintigraphy for dosimetry. We tested for differences of volume of interest (VOI) and region of interest (ROI) methodsMaterials and Methods: Patients with carcinoid disease underwent PET/CT with a diagnostic dose of 90-240 MBq of [68Ga]-DOTATOC (90min. p.i.) and serial gamma scintigraphy scans using Ga-67-DOTATOC (at 4, 24, 48 and 72 h p.i). VOIs were determined by segmentation using the Analyze software (VS 7.0, Mayo Clinic, Rochester, MN) for the CT data sets and manual ROI drawing on the PET datasets for lungs, liver, spleen, kidneys and the total body. Organ weight (from CT) and residence times (from PET + planar) were introduced into OLINDA/EXM (Vanderbilt University, Nashville, TN) and organ absorbed doses were determined.Results: The Ga-68 dose conversion factors determined by OLINDA/EXM were 0.11 mGy/MBq to the kidneys, 0.09 mGy/MBq to the liver, 0.04 mGy/MBq to the lungs, 0.22 mGy/MBq to the spleen and 0.02 mGy/MBq to the whole body for the VOI method. Results of the ROI method were calculated respectively: 0.19 mGy/MBq to the kidneys, 0.09 mGy/MBq to the liver, 0.05 to the lungs, 0.26 to the spleen and 0.03 mGy/MBq to the whole body. For Ga-67DOTATOC (including factor 5 for the Auger electrons) were 0.60 mGy/MBq to the kidneys, 0.55 mGy/MBq to the liver, 0.25 mGy/MBq to the lungs, 1.15 mGy/MBq to the spleen and 0.15 mGy/MBq to the whole body for the VOI method and respectively 1.00 mGy/MBq to the kidneys, 0.55 mGy/MBq to the liver, 0.30 mGy/MBq to the lungs, 1.35 mGy/MBq to the spleen and 0.20 mGy/MBq to the whole body for the ROI method.Conclusions: The differences in calculated doses for the two methods are most probably due to the defining the exact organ positions. These results demonstrate the feasibility and the necessity of an individualised pretherapeutic dosimetry approach for RPT using a VOIs based dosimetry..

P747 Ga-68-DOTATOC PET/CT 3D lesion quantification by the newly developed semi-automatic IDL-software tool “QuantScan”. M. Hofmann, T. Weitzel, F. Corminboeuf, T. Krause; Clinic of Nuclear Medicine, Molecular Imaging and Therapy Group (MIT-Bern,CH), Inselspital, Bern, Switzerland. Aim: Ga-68-DOTATOC/NOC PET/CT scans yield high contrast “hot spot” imaging. This enables automatic identification of local maxima. In case of small objects the image information has to be corrected by recovery coefficients for partial volume effects. In this study we present an easy-to use software for 3D evaluation and automatic recovery correction for phantom and patient scans.Methods: The software is developed in IDL 6.2 (Interactive Data Language) on a Windows XP platform. Initial starting points of the iterative approximation of the 3D activity concentrations are local maxima of measured intensity. The method assumes that the measured intensities represent a strictly circumscribed homogeneous ellipsoid. Moreover a 3-dimensional Gaussian spatial transfer function of suitable half width is assumed. The ellipsoid is defined by x,y,z coordinates, the radius and in first order assumption an homogeneous intensity distribution. Convolution of the ellipsoid by the spatial transfer function results in a 3-dimensional image and accordingly a 3-dimensional dataset, which simulates the results of corresponding measurements. Using a numerical fit algorithm the coordinates and parameters of the ellipsoid are systematically varied and the simulated measurement is then iteratively matched by a least squares fit to the measured data. The parameters found for the ellipsoid yield the size and the intensity of the lesion, which are then converted to concentration by multiplying with calibration factors derived from phantom studies. Datasets from phantoms filled with 68-Ga-DOTATOC (recovery calibration) and from patients undergoing Ga-68 DOTATOC PET/CT (Biograph, Siemens, Erlangen) were evaluated. Results The 3D quantification of small lesions by the “Quant-Scan” software yielded in spherical lesions <20mm diameter up to >30% higher activity concentrations than the inbuilt 2D ROI method. Fit, correction for recovery and quantification can be performed by a rapid one-step procedure. Conclusion This easy to use software enables the automatic evaluation of phantom scans and a semi-automatic 3D determination of activity concentrations in somatostatin pos. lesions of “hot spot imaging” Ga-68-DOTATOC/NOC scans. Incorporation of activity variations over time by list mode is currently under evaluation.

P748 Automated thoracic and abdominal computed tomography segmentation using the belief functions theory: application to 3D internal dosimetry A. Dieudonné1, P. Zhang2, P. Vannoorenberghe3, I. Gardin4; 1Laboratoire Quant.I.F., Université de Rouen, France, 2Laboratoires Quant.I.F. and LITIS, Université de Rouen, France, 3Laboratoire THR, Université de Toulouse, France, 4Centre Henri Becquerel and Laboratoire Quant.I.F., Rouen, France. Aim: Segmentation of CT images is an important step in 3D internal dosimetry. To this end, an automated method (SIPEC) was developed to delineate organs using the belief functions theory.Materials and Methods: Each VOI to be segmented is associated to a class which can be characterized by a specific value CVOI. Belief functions are used to evaluate the membership degree of voxel V to one of the predefined VOIs. Information extracted from V and its neighbours Vi are aggregated using a 3D filter dealing with spatial distance between voxels. The more the voxel Vi is close to V, the more the information coming from Vi is reliable. The algorithm was applied on 10 CT scans (pixel size 0.98x0.98 mm2, slice thickness 3 mm, 120 kV). For each organ (i.e. lungs, liver, kidneys and spleen), the algorithm was applied on a part of the CT volume. Firstly, lungs were segmented using 2 classes with C-values defined by the Kmeans clustering method (Bezdeck and Kluwer Ac. Pub. 1999). Secondly, liver and kidneys were segmented using 3 classes with C-values defined by local mean HU measurements, corresponding to fat, liver and kidney. Thirdly, spleen was segmented using 3 classes corresponding to fat, kidneys, and spleen using local mean HU measurements. Automated segmentation was compared with manual segmentation using the volume difference and the agreement (overlap) index.Results: For an organ segmentation, the computation time was between 5 and 20 min with SIPEC (2.5 GHz, RAM of 1 GByte) depending on the number of

S374

classes and the volume size to classify. On the 10 patients, manual correction was needed for none on lungs, 1 on spleen, 2 on kidneys and 7 on liver, mostly due to inter-costal structures. A region growth algorithm will be added to improve the method. The mean volume differences between manual and SIPEC segmentation, without manual correction, were 5.0%, 5.7%, 6.2% and 7.5% for lungs, liver, kidneys and spleen, respectively. The corresponding mean agreement indexes were 0.94, 0.90, 0.88 and 0.84.Conclusions: The algorithm allows delineating organs on thoracic and abdominal CT images and will be integrated in a 3D internal dosimetry dedicated software.

P749 Radionuclide Dosimetry preliminay report

in

90Y-DOTATOC

Therapy

:

S. Barucca1, A. Berbellini1, S. Ancidei1, C. Cidda1, F. Capoccetti1, F. Ferretti1, S. Sivolella1, S. Fattori2, G. Rossi2, E. Brianzoni1; 1Nuclear Medicine Oncology Dept Macerata Hospital, Macerata, Italy, 2Medical Physic Macerata Hospital, Macerata, Italy. AIM Neuroendocrine tumours (NET) frequently express somatostatin receptors (SSTRs) and this allows the use of radiolabeled somatostatin analogues as targeted therapy. One of these analogues is 90Y-DOTATOC with tumor response rate up 30%. The aim of our study, is to evaluate the dosimetric parameters for the patients (pts) with diagnosis of NET before therapy with 90Y-DOTATOC and to check therapeutic effects. MATERIALS AND METHODS From October 2004 to March 2006 we studied 25 pts with diagnosis of NET: 17 males and 8 females, mean age 62 yy, range 27÷84 yy, 15 Gastroenterpancreatic, 3 Merkel Cell, 4 Medullary Thyroid, 1 Thymus Carcinoma, 2 Bronchial Carcinoid; 14/ 25 pts with nodal and distant metastases. All pts positive to 111In-Octreotide Whole Body Scan (WBS) have been submitted to radionuclide dosimetry with 111In-DOTATOC adninistering 1850 MBq i.v., the renal uptake has been reduced by aminoacids infusion; the same protocol has been used during theraphy. The dosimetric data (DD) have been obtained from: 11 blood samples (at 5, 9, 17, 25, 42, 55 min; 2, 5, 21, 23 h post i.v.), 9 urinary samples (2, 4, 6, 10, 18, 23, 28, 37, 55h), 5 WBS (1, 5, 24, 44, 78h). Computed Tomography and SPECT have been used for lesion localization and organs volumetric calculation. All DD have been introduced in MIRDOSE 3.1, leading to individualized therapeutic regimes Have been adminitered from 1480 to 13.801 MBq in different cycles (1÷5). Tumour responses have been classified by WHO criteria at 3 month intervals with clinical, biochemical and radiological evaluation. RESULTS We found no side effetcs. The predicted absorbed doses result 0.07±0.04 (red marrow), 2.5±1.7(kidneys),4.2±4.7 (spleen), 0.6±0. (liver), 2.4±0.4 (bladder), and 14.2±16.9 (range: 1.2÷55.7) (tumour) mGy/MBq. We obtained the therapeutic following results: stable disease (SD) in 11/25 (44%) pts, partial response (PR) in 7/25 (28%) pts, progression of disease in 5/25 (20%) pts, complete response (CR) in 2/25 (8%) pts. In 7/25 we have observed max kidney dose range 4055 MBq÷10323 MBq and in these pts we found 3 PR, 3 SD and 1 CR. CONCLUSION The obtained results confirm the usefulness of dosimetry in the personalized therapy sparing side effetcs. Moreover our results in therapy efficacy are in agreement with the literature data. To improve successful rate, the treatment should be carried out as soon as possible, considering a combination of different radioisotopes, multireceptor targeting and use of radiosensitizers, in a multidisciplinary therapeutic approach.

P750 Repeated radionuclide therapy of bone metastases with rhenium-188 hedp: a kinetic study K. Reichmann, S. Guhlke, R. Roedel, S. Ezziddin, H. Brockmann, J. Bucerius, H. Biersack, H. Palmedo; UNiversity Bonn, Bonn, Germany. Objectives: The aim of this study was to evaluate effective halflife and uptake of Re-188 HEDP in normal tissue and bone metastases.Methods: An activity of 3000+-370 MBq Re-188 HEDP was administered to 26 patients (37 therapies) with multifocal bone metastases of prostate carcinoma. Nineteen patients received a single injection, 7 patients underwent repeated injections. For kinetic calculations, five static whole-body scans were acquired after each application (directly p.i., 1.5, 18, 24, and 42 hours p.i., PRISM2000/Philips, MEGP). Using the ROI-technique, 1-3 metastases, left and right femur, soft tissue and whole body were evaluated. From the extracted values, we calculated the following parameters: mean effective halflives (eff HL), the eff HL-ratios of soft tissue/femur and metastases/femur (individually for all patients) and the uptake in the metastases expressed as the ratio of metastasis/whole body.Results: For the eff HL of soft tissue, femur and metastases we obtained 10.0 h +-2.5, 9.6 h +- 2.8 and 15.3 h +9.1, respectively. The eff HL-ratios soft tissue/femur and metastases/femur were calculated with 1.18+-0.52 and 1.61+-1.5, respectively. The mean uptake of all metastases was 1.42% +-1.16. The uptake of the metastases that underwent repeated therapies, was 1.23% +-0.89, 1.10% +-0.63 and 1.34% +-0.74 for the first, second and third therapy, respectively. This means that the uptake during the second therapy was in the mean 11% lower than during the first (in 5 patients higher, 7 diminished and 2 unchanged). Compared with the second, the uptake during the third therapy was 21% higher ( in 3 patients increased, 4 diminished). The eff HL of repeatedly treated metastases was 15.29 h +-3.65, 20.92 h +-7.9 and 18.85 h +-7.3 during the first, second and third therapy, respectively. Thus the eff HL during the second therapy was 37% higher than in the first one (9 pat. increased, 3 diminished). Compared with the second, the third treatment showed a reduction of eff HL by 10% (3 pat. increased, 3 diminished).Conclusions: The biological elimination in the metastases was lower than that in soft tissue and femur indicating a higher residence time in the metastases. In repeatedly treated bone metastases, the uptake remained constant, the effective halflife (and therefore the irradiation time) was prolonged. These data confirm that higher radiation doses can be achieved by repeated radionuclide treatments.

P751 Comparison of quantification and image degrading factors with different Iodine isotopes (I-123, I-124, and I-131) E. Rault, S. Vandenberghe, R. Van Holen, J. De Beenhouwer, I. Lemahieu; MEDISIP, Ghent, Belgium. The purpose of this study was to compare quantification and image degrading factors with different iodine isotopes currently used in nuclear medicine: I-123 and I-131 for SPECT imaging

P752 Concomitant Dosimetry during 177-Lu labelled Radionuclide Therapy in comparison with Conventional Dosimetry using 111-In labelled Peptides D. Heute, G. Dobrozemsky, B. Warwitz, M. Gabriel, E. von Guggenberg, I. Virgolini; University of Innsbruck, Innsbruck, Austria. Aim: Proove the feasibility of concomitant dosimetry during radionuclide peptide therapy with 177-Lu-DOTA-tate and 177-Lu-lanreotide and secondly compare the resulting organ and tumour doses to those calculated by standard 111-In-ocreotide and 111-In-lanreotide respectively.Materials and Methods: We report on 12 patients receiving 177-Lu labelled peptide therapy (8 male and 4 female, 45 to 74 years old). 2 patients suffered from gastrinoma, 2 had carcinoid of the bowel and 1 carcinoid of the lungs. There were 2 pts with NET (neuroendocrine Tumour) of the pancreas, 1 with NET of the prostate and 1 NET with unknown primary. Finally there were 2 iodine negative thyroid carcinomas and 1 patient with MTC. Routinely we applied 7.4 GBq 177-Lu-DOTA-tate or 177-Lu-lanreotide, respectively. Whole body scans were taken at 4, 24, 48 and 72 h p.i. Additionally, whole body doses were measured directly after the injection of the therapeutic activity and prior to each scintigram. Imaging was performed with a two headed gamma camera. The dosimetric measurements were normalised to moment of application of the activity using dose rates from two stationary gamma dose rate meters in opposing view. Secondly standard dosimetry with 111-In-DOTA-Tyr3-octreotide or lanreotide was performed in all patients. Dose calculations were done for the tumour lesions as well as for kidneys, liver and spleen using the Olinda dosimetry program.Results: All tumour lesions showed high uptake of the 177-Lu labelled radionuclide. Tumour and organ doses by means of the 177-Lu dosimetries were within the range of the observational error of the results received from the standard dosimetries using 111-In-DOTA-Tyr3-octreotide or 111-In-lanreotide, respectively.Conclusions: Concomitant dosimetry during the therapy with 177-Lu labelled peptides is feasible and easy to perform. This new method gives valid results even in clinical routine. Additional dosimetric scintigrams with 111-In prior to therapy can be avoided resulting in earlier treatment.

P753 Biodistribution of mAB YAML568 labelled with myeloid leukemia

111

In in acute

F. M. Mottaghy, G. Glatting, M. Müller, B. Neumaier, B. Koop, K. Hohl, C. Friesen, G. Hale, N. M. Blumstein, D. Bunjes, S. N. Reske; University Hospital Ulm, Ulm, Germany. Targeted radiation to the hematopoetic organs allows an enhanced delivered dose to the bone marrow while sparing non-targeted organs. This could potentially result in a better outcome. The biodistribution of 111In-labeled anti-CD45 antibody in humans using the rat IgG2a monoclonal antibody YAML568 that recognizes a common CD45 epitope present on all human leukocytes was evaluated. Eight patients scheduled for targeted radiotherapy as part of conditioning prior to bone marrow transplantation received YAML568 labeled with 122±16 MBq of 111In i.v. followed by serial blood sampling, urine collection and planar gamma camera imaging up to 144 h post injection. Time-activity curves were obtained using region of interest analysis in the accumulating organs and residence times were calculated. An estimate for the radiation absorbed doses for each organ per unit administered activity of 90Y was calculated using OLINDA/EXM. The first patient received no unlabeled antibody preload. The second two received a preload dose of 0.15 mg/kg. The last 5 received a preload dose of 0.5 mg/kg. YAML568 was well tolerated by all patients. In the 3 patients receiving no or low antibody preload an unfavorable biodistribution with a high initial accumulation of activity in the liver (37%) and the spleen (34%) was seen. In the patients receiving 0.5 mg/kg antibody preload the estimated radiation absorbed doses for red bone marrow, spleen, liver, kidneys and total body were 6.4±1.2, 19±5, 3.9±1.4, 1.1±0.4 and 0.6±0.1 mGy/MBq, respectively, demonstrating preferential red marrow targeting. The amount of unlabeled antibody preload per body weight has a significant influence on the estimated red marrow absorbed dose (p=0.003, R=0.9). The anti-CD45 monoclonal antibody YAML568 labeled with 90Y is suitable for delivering selectively radiation to hematopoietic tissues. A preload dose of 0.5mg/kg led to a favourable biodistribution, however the optimal dosage needs to be further evaluated.

P754 The comparative effects of gene modulators on thyroid specific genes and radioiodine uptake M. Tuncel1, D. Aydin2, E. Y. Cankaya3, U. H. Tazebay3, D. Guc2, A. L. Dogan2, B. Tasbasan2, O. Ugur1; 1Hacettepe University Faculty of Medicine Department of Nuclear Medicine, Ankara, Turkey, 2Hacettepe University Oncology Institute Department of Basic Oncology, Ankara, Turkey, 3Bilkent University Department of Molecular Biology and Genetics, Ankara, Turkey. Introduction: Aim of this study was to comparatively investigate the effects of 5-azacytidine -C (5-Aza), trichostatin-A (TSA) and all-trans retinoic acid (ATRA) on mRNA expressions of Na/I Symporter (NIS), Thyroglobulin (Tg), Thyroid peroxidase (TPO) and Thyroid stimulating hormone receptor (TSH-R), and radioiodine (RAI) uptake in cancer and normal thyroid cell lines.Methods: In order to determine the maximum tolerated doses of TSA, 5-AZA and ATRA, MTT (methyl-thiazol-tetrazolium) toxicity tests were performed in normal thyroid (Nthy-ori 3-1) and metastatic papillary thyroid carcinoma (B-CPAP) cell lines. Cell lines were treated with 10 ng/ml TSA, 5 µM 5-Aza, 1µM ATRA according to the MTT results. rTSH was applied with a selected dose of 100 ng/ml. After the treatment, NIS, Tg, TPO and TSH-R mRNA levels were detected by Real Time-Polymerase Chain Reaction (RT-PCR) and RAI uptakes were measured using well counter as counts/cell number.Results: 5-Aza increased TSH-R mRNA expression in both of the cell lines and decreased TPO, NIS and Tg mRNA levels in cancer cell line. In normal thyroid cell line 5-Aza increased TPO mRNA levels two fold and made no differences in NIS and Tg mRNA levels. TSA treatment repressed NIS and Tg mRNA levels and made no change on other thyroid specific genes investigated in cancer cell line. In normal thyroid cell line, TSA increased TSH-R mRNA levels in 72 hour and created no important difference in other genes. ATRA, repressed the TSH-R mRNA levels in normal thyroid cell line and increased the TPO ve Tg mRNA levels slightly in both cell lines. Furthermore, in short term treatment, ATRA repressed NIS gene expression slightly but in long term this repression turned to basal levels. 5Aza, TSA and ATRA did not make any significant changes in RAI uptake in cancer cell line but rTSH increased RAI uptake significantly. In normal thyroid cell line TSA and ATRA decreased RAI uptake (to 1/10 and 1/2, respectively) but 5-Aza and rTSH increased RAI uptake significantly (2 and 4 fold respectively).Conclusions: 5-Aza is a promising agent for the radioiodine treatment of thyroid diseases. Further in vitro and in vivo studies are needed to support our findings and potential clinical usage of this agent.

P755 Amifostine successfully protects the kidneys after high dose 177 0 3 [ Lu-DOTA ,Tyr ]octreotate E. J. Rolleman, F. Forrer, B. Bernard, R. Valkema, M. Bijster, E. Krenning, M. de Jong; Erasmus Medical Centre, Rotterdam, The Netherlands. In peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues, the kidneys are the major dose-limiting organs. Preventing renal uptake and toxicity enables higher doses of radiolabelled peptide to the tumour. Positively charged amino acids (e.g. lysine) are commonly used to reduce kidney proximal tubule reabsorption of these radiolabelled compounds. Further improvement can be achieved by use of radioprotectors like amifostine. This drug selectively protects healthy tissue by higher uptake in healthy tissues as compared to the tumour. Aim To investigate if amifostine (A) in comparison to lysine (L) treatment can prevent renal damage after PRRT with high dose [177Lu-DOTA0,Tyr3]octreotate (177Lu-TATE). Materials & Methods Male Lewis rats were injected with 278 or 555 MBq 177Lu-TATE to create renal damage, resulting in kidney absorbed doses of 46 and 92 Gy. Some groups of rats received also A treatment (200 mg/kg iv just prior to177Lu-TATE and 25 mg/kg sc for 7 following days) or co-injection of L (400 mg/kg). Urinary protein was measured weekly. 130 days after PRRT a SPECT scan with a four-detector multi-pinhole SPECT camera (NanoSPECT, Bioscan) was performed 4 hours after 50 MBq 99mTc-DMSA to quantify tubular function. Shortly thereafter, rats were sacrificed, blood samples were taken and kidneys were evaluated for histological damage. Results Treatment with 555 MBq 177Lu-TATE resulted in high serum creatinine (572±275 umol/L); A and L treatment significantly prevented this rise (138 ± 35, P<0.001; 130 ± 88, P<0.001, respectively). Treatment with 278 MBq 177Lu-TATE did not significantly change serum creatinine values. PRRT-induced proteinuria was also significantly lowered by treatment with A or L. Rats treated with 555 MBq 177Lu-TATE plus A or L had histological damage scores comparable with treatment with 555 MBq 177Lu-TATE alone. In contrast, A significantly reduced the histological damage scores after 278 MBq 177Lu-TATE (P<0.01). SPECT measurement of kidney uptake of 99mTc-DMSA 130 days after 177Lu-TATE showed a good correlation with 1/creatinine (r2=0.778, P<0.001). Conclusion Amifostine and lysine effectively prevented functional renal damage caused by high dose 177Lu-TATE. Amifostine only reduced histological damage in the lower radioactivity group. Both compounds may be used in clinical PRRT to maximize anti-tumour efficacy.

P756 Targeted radioiodine therapy of hepatoma using the sodium iodide symporter and the albumin promoter L. Chen1, A. Altmann2, R. Zhu1, L. Guo1, W. Mier2, M. Eisenhut2, U. Haberkorn2; 1University of Shanghai, Shanghai, China, 2University of Heidelberg, Heidelberg, Germany. We investigated the feasibility of radioiodine therapy targeting hepatoma cells (MH3924A) by tissue-specific expression of the human sodium iodide symporter (hNIS) gene directed by the murine albumin enhancer and promoter (mAlb). Methods: The cell-specific transcriptional activity of mAlb was examined by a luciferase assay in several transiently transfected cell lines. MH3924A cells were stably transfected with the recombinant retroviral vector, in which hNIS cDNA expression was driven by mAlb and coupled to hygromycin resistance gene using an internal ribosomal entry site (IRES). Functional hNIS expression in hepatoma cells was confirmed by an iodide uptake assay. In imaging studies, the tumor-bearing ACI rats were intravenously injected with 131I and imaged with a gamma camera. Biodistribution was studied at

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and I-124 for PET imaging.Methods: The imaging characteristics of each isotope were investigated by both measured and simulated data. A planar phantom composed of a circular background with low activity and several hot spots of different sizes (from 4-20 mm diameter) was used to determine the contrast recovery as a function of size of those hot spots. The contrast between the hot spots and background was 4:1. The images from this phantom are also used to investigate the noise in the images. Planar and tomographic acquisitions of I-123 (with a low energy collimator and a medium energy collimator) and I-131 (with a high energy collimator) have been compared and simulations of I-124 PET images will be added to those results. The GATE software was used to perform all simulations and allows to study effects of downscatter.Results: The accuracy of the Monte Carlo simulations was demonstrated by the agreement between experimental and simulated results. Results show that the amount of downscatter from high energy peaks (for I-123 and I-131) into the main energy window, strongly depends on the collimator choice. This downscatter is responsible for a decrease of the image quality and reduces the accuracy of quantification. As expected, contrast is improving with the increasing object size (from 33.4% for an object of 4mm to 83.5% for an object of 20mm imaged with I-123 on medium energy collimators). I-123 associated with the medium energy collimator offers the best contrast for the 20 mm diameter sphere (83.5%), compared to I-123 with the low energy collimator (75.9%) or to I-131 with the high energy collimator (57.2%). Downscatter corrections (background subtraction and triple energy window) have been investigated and a gain of 20% has been established with the triple energy window method.Conclusions: In the case of I131 and I-123, image quality and quantification are degraded by scatter and penetration in the collimator. I-123 is best imaged with a medium energy collimator to reduce penetration of the higher energy peaks. Results have shown that correction for downscatter of high energy peaks significantly improves quantification of I-123 and I-131.

30 min and at 1, 3, 6, and 25 h after injection of 131I. Toxic effects of 131I on hepatoma cells were studied in vitro and in vivo. Results: Stably transfected MH3924A cells concentrated 125I up to 240-fold higher than the wild-type cells. The iodide uptake in stably transfected cells was inhibited by ouabain and sodium perchlorate, but increased by DIDS. An in vitro clonogenic assay revealed an 86% decrease in colony number in stably transfected cells after exposure to 3.7 MBq/mL of 131I, and only about 8% in hNIS-negative control cells. Furthermore, the in vivo study showed intense tracer accumulation in hNIS-expressing tumors after administration of 131I. At 3 h post intraperitoneal (i.p.) injection, the transfected tumors accumulated 131I 19.2-fold higher than the parental tumors in a biodistribution study. Moreover, administration of a therapeutic dose of 131I resulted in an inhibition of hNIS-expressing tumor growth, whereas control tumors continued to increase in size. Conclusion: A therapeutic effect of 131I on hepatoma cells in vitro and in vivo has been demonstrated following tumor-specific iodide uptake induced by mAlb-directed hNIS gene expression. Since a stable transformed cell line has been used in these experiments the clinical potential of this strategy has to be evaluated after in vivo transfection of hepatoma cells.

P757 The genotoxic effects in lymphocyte cultures of infants treated with radiosynovectomy by using Yittrium-90 citrate colloid. C. Turkmen1, S. Ozturk2, S. Unal1, B. Zulfikar3, O. Taser4, Y. Sanli1, K. Cefle2, O. Kilicoglu4, S. Palanduz2; 1Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey, 2 Department of Internal Medicine, Division of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey, 3Department of Pediatric Hematology, Institute of Oncology, Istanbul University, Istanbul, Turkey, 4Department of Orthopedics and Traumatology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. The aim of this study was to investigate the genotoxic effect on the peripheral blood lymphocytes potentially induced by Yittrium-90 citrate colloid (Y-90) in pediatric populations undergoing radiosynovectomy for hemophilic synovitis, by using chromosomal aberration analysis (CA) and the micronuclei (MN) assay for detecting chromosomal aberrations, as well as the sister chromatid exchanges (SCE) technique for assessed DNA damage. Methods: Cytogenetic analyses were undertaken in 12 boys with hemophilic synovitis who underwent radiosynovectomy with Y-90. The mean age of patients at the time of treatment was 15,3±1,8 years (range: 12-18 years). A dose of 185 MBq of colloidal 90Y-citrate diluted with saline to a total volume of 4 mL was injected to the 12 knee joints in 12 children under aseptic conditions. After injection of the radiopharmaceuticals, 20-40 mg of dexamethasone was injected using the same needle, and then withdrawn. Following the injection, some pressure on the injection site was applied and passive movement of the joint was carried out to achieve a homogenous intraarticular distribution of the radionuclide. Finally, the treated joint was compressed with an elastic bandage and immobilized for 2 days. CA, MN and SCE were evaluated before, 2 and 90 days after radiosynovectomy from the peripheral lymphocytes of the patients. Additionally, joint retention and extraarticular spread of the radionuclide were evaluated by using gama camera imaging at the 2nd and 48th hours after the procedure. Whole-body and static images using a medium-energy collimator and energy window of 55-285 keV for the imaging of 90Y Bremsstrahlung were obtained. Results: The procedure was well tolerated in all children, and there was no extra-articular activity due to extra-articular leakage of radioactive material in control scintigrams. Of the 12 patients, the mean frequency of chromosome aberrations (0,25±0,45/1000 cells) determined prior to the onset of therapy was not significantly increased in comparison with control values obtained 2 days (0,33±0,49/1000 cells) and 90 days (0,08±0,29/1000 cells) after therapy (p=1,0 and p=0,625). In the analysis of MN and SCE, there was no significant differences between baseline and control levels in the analyses performed 2 and 90 days after radiosynovectomy ( p=0,139 and p=0,127 for MN analyses and p=0,885 and p=0,727 for SCE analyses respectively). Conclusion: The results of our study showed that Y-90 radiosynovectomy does not induce genotoxic effects on the peripheral blood lymphocytes in the pediatric population.

catheterization/administration procedure did not provoke marked side-effects, save a transient dip in appetite in some animals. However, procedure related complications have occurred occasionally; due to overt backflow of microspheres into the gastroduodenal artery, hence the minor curvature of the stomach, two pigs have met their demise prematurely. One other pig developed a (subclinical) gangrenous cholecystitis. No persistent alterations in serum levels of relevant blood parameters or myelosuppression was seen. Typically, during autopsy, partial necrosis of the liver and compensatory hypertrophy and hyperplasia was observed.Conclusions: this dose escalation study shows that pigs can easily withstand liver doses of up to 150 Gy. Complications that have occurred all were explicitly related to the administration procedure. Essential in this respect is that the flush-out pressure is kept low. In patients, inadvertent retrograde flow, particularly into the gastroduodenal artery, should be monitored or even prevented by placing a Gianturco coil. Additionally, a cholecystectomy beforehand seems advisable.

P759 99m

Noninvasive scintigraphic detection of tumor with Tc99m DTPA- deoxyglucose ( Tc-DTPA-DG): experimental study Y. Chen1, F. Q. Xiong1, Q. X. Yang1, W. Z. Huang1, L. He2; 1Affiliated Hospital, Luzhou Medical College, Luzhou, Sichuan, China, 2West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China. Objective: Glucosamine is a highly attractive scaffold for a glucosyl ligand and shows activity with GLUTs (glucose transporters) and hexokinase. In this study DTPA-glucosamine (DTPADG) was synthesized by conjugating D-glucosamine to DTPA and labeled with 99mTc. We investigated 99mTc-DTPA-DG for tumor detection.Methods: The biodistribution and imaging of 99m Tc-DTPA-DG in mammary tumor-bearing mice were comparison to that in mice with oleum terebinthinae inflammation control group. The mice were injected with 3.7MBq 99mTc-DTPADG in 0.1mL through the tail vein.Results: 99mTc-DTPA-DG accumulated in the tumor up to 2.10±0.02 percentage injected dose per gram (%ID/g) at 2hr after injection (vs. 0.81±0.03 %ID/g in the inflammation). Tumor-to-contralateral muscle ratios were 5.01±1.02.Inflammation -tocontralateral muscle ratios were 1.2±0.08. Gamma camera imaging visualized the tumor tissue at 2hr after injection. The tumor-to-background ratios (3.8±0.95) at 2hr were significantly (P < 0.05) higher in mammary tumor-bearing mice than the inflammation-to-background ratios (1.2±0.62) in the inflammatory mice.Conclusions: 99mTc-DTPA-DG showed excellent tumor targeting. 99mTc-DTPA-DG could be used as an imaging agent for targeting tumor.

P760 Preparation and imaging research of 188 deoxyglucose ( Re-DTPA-DG) in MCF-7 mice

188

Re-DTPA-

Y. Chen1, F. Q. Xiong1, Q. X. Yang1, W. Z. Huang1, L. He2; 1Affiliated Hospital, Luzhou Medical College, Luzhou, Sichuan, China, 2West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China. Objective We investigated the preparation, imaging and therapeutic effect of 188Re-DTPA-DG. Methods The labeling of DTPA-DG with 188Re was performed in the presence of stannous ion, sodium D-gluconate and pH 5.5 after 3 hr incubation at 37 degree. The raiolabeling yields of 188 Re-DTPA-DG were determined by using paper chromatography developed with acetone and saline (0.9% NaCl). The imaging of 188Re-DTPA-DG in nude mice bearing MCF-7 mammary cancer cell was injected into the tail vein and evaluated at 2, 4, 8, 12 and 24hr. 188Re-DTPA-DG of 0.1mL 92.5GBq/L was injected into the tail vein. Tumor volume was recorded every two or three days for 21 days. Results The radiochemical purity of the complex was 95.0%. In imaging study, the tumor-to-nontumorus ratio (T/NT) at 12h and 24hr post intravenous injection was 5.9,7.8, Respectively. Tumor volume of between the two groups differ greatly at 21 day by 823.6±50.58 mm3 in 188Re-DTPA-DG treated group and 1162.7±73.08 mm3 in control group (P<0.01). Conclusions 188Re-DTPA-DG showed excellent tumor targeting and effect of tumor growth suppression. 188Re-DTPA-DG could be used as a potential agent for the internal radiotherapy of tumor.

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P761

Radioembolization of the liver with holmium-166 poly(L-lactic acid) microspheres in healthy pigs

Lu-DOTA -Tyr -octreotate is more suitable than Lu0 3 DOTA -Tyr -octreotide for therapy of human midgut carcinoid tumours

M. A. D. Vente1, J. F. W. Nijsen1, T. C. de Wit1, J. Seppenwoolde2, G. C. Krijger3, P. R. Seevinck2, W. Bult1, R. de Roos1, B. A. Zonnenberg1, M. G. G. Hobbelink1, P. P. van Rijk1, A. D. van het Schip1; 1Dept. of Nuclear Medicine, University Medical Center, Utrecht, The Netherlands, 2Image Sciences Institute, University Medical Center, Utrecht, The Netherlands, 3 Dept. of Radiation, Radionuclides and Reactors, Delft University of Technology, Delft, The Netherlands. Aim: one of the most effective treatment modalities for cancer is radiation therapy. However, in the treatment of unresectable liver cancer, due to the relative intolerance of liver parenchyma to ionizing radiation, the role of external radiation therapy traditionally has been limited. Recently clinically introduced, internal radiation therapy with yttrium-90 loaded microspheres seems to be a promising new treatment approach. However, since yttrium-90 is a pure beta-emitter (Eȕmax = 2.27 MeV), it lacks possibilities for good quality imaging. Therefore, poly(L-lactic acid) microspheres loaded with holmium-166, a combined beta-gamma emitter (Eȕmax = 1.84 MeV (51%), 1.78 MeV (48%); EȖ = 0.081 MeV) and also highly paramagnetic, allowing for (quantitative) SPECT and MR imaging, respectively, have been developed. An extensive toxicity and biodistribution study in healthy pigs has been conducted.Materials and Methods: in nontumour bearing pigs holmium-166 loaded microspheres were injected into the proper hepatic artery, delivering absorbed liver doses of up to 150 Gy. Subsequently, biodistribution was assessed using nuclear and MR imaging. During 30 or 60 days the animals were monitored for clinical side-effects and complications. Blood samples were collected twice a week. After termination, a post-mortem examination was executed.Results: if carried out correctly, the

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E. Forssell-Aronsson1, C. Svärd2, L. Kölby2, P. Bernhardt1, A. Schmitt1, V. Johanson2, H. Ahlman2, O. Nilsson3; 1Radiation Physics, Göteborg, Sweden, 2Surgery, Göteborg, Sweden, 3Pathology, Göteborg, Sweden. Receptor mediated radiation therapy is a new treatment modality for disseminated neuroendocrine (NE) tumours and several combinations of radionuclides and somatostatin analogues have been developed and compared. Some of them are 177Lu-DOTA0-Tyr3-octreotate and 177Lu-DOTA0-Tyr3-octreotide. No in vivo data comparing these particular radiopharmaceuticals have been reported. The aim of this study was thus to compare the biodistribution and therapeutic effects of 177Lu-DOTA0-Tyr3-octreotide and 177Lu-DOTA0-Tyr3octreotate in nude mice bearing human midgut carcinoid tumours. Material and methods Biodistribution and therapeutic studies were performed in nude mice transplanted with the human midgut carcinoid tumour cell line, GOT1. The animals were i.v. injected with 15 MBq (0.5 µg) of 177Lu-DOTA0-Tyr3-octreotate or 15 MBq (0.5 µg) of 177Lu-DOTA0-Tyr3-octreotide. The biodistribution was compared up to 13 d after injection. The absorbed dose was estimated. The tumour response was followed up to 150 days after injection. Results The activity concentration in tumour tissue was significantly higher for animals given 177Lu-DOTA0-Tyr3octreotate compared to animals given 177Lu-DOTA0-Tyr3-octreotide (e.g. 16±1 %IA/g versus 8±2 %IA/g, mean ± SEM, 1 day after injection, p=0.0006). The mean absorbed dose in tumour was higher in animals given 177Lu-DOTA0-Tyr3-octreotate (46±4 Gy versus 17±3 Gy). The reduction of tumour volume was significantly better in animals given 177Lu-DOTA0-Tyr3-octreotate compared to animals given 177Lu-DOTA0-Tyr3-octreotide (p=0.003). The mean tumour volume

P762 Serial Tc-99m MAG3/TER measurements for the evaluation of renal function after Y-90 DOTA-TATE peptide receptor radionuclide therapy (PRRT) R. P. Baum, V. Prasad; Zentralklinik Bad Berka, Bad Berka, Germany. PRRT using Y-90 DOTA-TATE (Y90) in patients with metastasized neuroendocrine tumors can have detrimental effects on tubular renal function. Aim: To evaluate the relationship between the amount of radioactivity of Y-90 administered and renal function impairment.Methods: Group A1: 52 patients (age 59±11a) injected with 3.7±1.0GBq of Y-90 (1st cycle). Group A2: 37 patients (age 59±10.9a) followed up after a total of 6.9±1.4GBq of Y-90 (2nd cycle). Group A3: 20 patients (age 58±10.2a) followed up after a total of 10.17±1.62GBq of Y-90 (3rd cycle). Tubular extraction rate (TER) was determined in each patient using 110-185 MBq of Tc-99m MAG3 prior to and 3-5 months after therapy. Normalised values for TER (TERn) pre/post PRRT were compared (paired T-test). To evaluate the relationship between the changes in TERn and the activity administered (Pearson’s correlation coefficient), four categories were made: B1 (<3 GBq), B2 (3-6 GBq), B3 (6-10 GBq) and B4 (>10 GBq).Results: In group A1 there was a fall in TERn value by 2% as compared to 5% in group A2 and 9% in group A3. Baseline TERn values were 89%, 87% and 86% in group A1, A2 and A3 respectively. The fall in TERn became significant only after the second cycle (p=0.31, 0.05 and 0.029 in group A1, A2 and A3 respectively). There was an increase(!) in TERn by 1.5%±0.12 in B1; however, the groups B2, B3 and B4 showed a fall in TERn of 3.2%±0.12, 6.6%±0.17 and 8%±0.16, respectively. There was no correlation between the fall in TERn and the radioactivity administered in any of the groups, Pearson’s correlation coefficient being 0.30, 0.92, 0.25 and 0.43 in B1, B2, B3 and B4 respectively.Conclusions: Y-90 DOTA-TATE therapy results in impairment of renal function which becomes gradual and significant after the second cycle. There is no direct linear relationship between the amount of radioactivity administered and the change in renal function. Less than 3 GBq of Y-90 DOTA-TATE in the first cycle does not result in any impairment of renal function. Greater than 3 GBq of Y-90 DOTA-TATE can result in a gradual fall in renal function.

P763 Renal re-absorption of various radiopeptides can not be reduced by Lysine or Arginine M. Gotthardt1, J. van Eerd-Vismale1, M. Béhé2, F. H. Corstens1, W. J. G. Oyen1, O. C. Boerman1; 1Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands, 2Department of Nuclear Medicine, PhilippsUniversity, Marburg, Germany. Aim: Megalin-mediated renal tubular re-absorption (TR) of radiopeptides may cause nephrotoxicity in peptide-receptor radiotherapy (PRRT). We evaluated the ability of several agents to inhibit TR of different radiopeptides.Materials and Methods: Male wistar rats (4 per group, 250 g/rat) where injected i.v. with 1 MBq of 111In-labeled Octreotide (OCT), Minigastrin (MG), Bombesin (BOM), or Exendin (EX) after pre-injection of 20-40 mg of a potential inhibitor of TR or PBS as a control. As potential inhibitors, Arginine (Arg), Lysine (Lys), Poly-Glutamic acid (PGA) were used. In addition, Aminomix® (AM) and Gelofusine® (GF) were also tested. Rats were euthanized 20 h p.i. and dissected. Organ uptake was determined as % of injected activity per gram. Based on the results obtained, in a second set of experiments Arg, PGA, and Gelofusine® were combined to determine whether the effect of the combination of agents on TR would be additive. The localization of the peptides in the kidneys was investigated by autoradiography using a phosphor images.Results: TR of OCT could significantly be inhibited by Lys, AM, and GF (reduction by 40, 35, and 45%, respectively) but not by PGA. TR of MG was reduced by GF and PGA (by 50% and 85%, respectively) while AM and Lys did not show any effect. Kidney uptake of EX and BOM was not reduced by any of the tested substances. The combination of ARG and GF did not show any additive effect on the kidney uptake of OCT as compared to the single substances. Furthermore, this combination was also not able to inhibit TR of EX. Autoradiography showed localization of the different peptides in the renal cortex, indicating they all are re-absorbed in the proximal tubules.Conclusions: Our results indicate that TR of radiopeptides is a complicated process co-localization of the radiopeptides in the renal cortex would suggest megalin-mediated uptake. However, inhibitors of TR show selective action indicating towards involvement multiple uptake mechanisms. TR of EX and BOM was not be inhibited by the agents tested in this series of experiments suggesting that these peptides are taken up in the kidneys by a different mechanism.

P764 Use of spontaneous dog osteosarcoma model in the evaluation of tumor uptake and biological effects of 188ReHEDP D. Mathe1, T. Tripunoski2, G. Andocs1, L. Balogh1, A. Polyak1, P. R. Chaudhari3, G. A. Janoki1, O. Vaskova4; 1NRIRR, Budapest, Hungary, 2 Institute of Pathophysiology and Nuclear Medicine, Skopje, The Former Yugoslav Republic of Macedonia, 3Bhabha Atomic Research Institute, Mumbai, India, Mumbai, India, 4Institute of Pathophysiology and Nuclear Medicine, Medical Faculty, Skopje, Hungary. Aims. We studied the preparation and quality control of 188Re-HEDP and its uptake in spontaneous dog bone neoplasia. The possibility of predicting uptake of the radiopharmaceutical was examined by pretherapy 99mTc-MDP bone scintigraphy in each dog. Possible effect of the radiopharmaceutical on the tumor was investigated as well as dose limiting organs. Materials

and methods. 14 dogs with spontaneous osteosarcoma were enrolled. Animals received an activity between 1.1-2.1 GBq of 188Re-HEDP. Relative uptake of radiopharmaceutical in the tumor (T/NT ratio) was calculated by region of interest (ROI) analysis. Uptake of the radiopharmaceutical in the tumor was assessed by comparison to the total counts in the femur and whole body. Dosimetry was calculated on the basis of assessed tumor volume and the proportion of administered activity in the tumor. Laboratory blood counts and biochemical values were regularly checked for estimation of side effects. Results. On the basis of pretreatment MDP scans, a low, a medium and a high T/NT uptake group of animals was formed with 3-8-3 animals, respectively. The T/NT ratios of 188Re-HEDP uptake could be grouped in the same groups with only one animal falling from the medium to the low group. A mean dose of 5 - 12 15 Gy was calculated to be deposited in the tumors by repsective group. 12 dogs out of 14 died of progressive disease with a median survival of 61 days. Of the Low uptake group, 2 dogs of 14 showed stable disease and are still alive. Posttherapy MDP scan did not show decrease of tumor size. Conclusions. Spontaneously occuring osteosarcoma of dogs proved to be a model of high value in the studies of radionuclide therapy as a novel modality of osteosarcoma treatment. Further studies are warranted to elucidate the origins of osteosarcoma radiosensitivity as detected by our experience and previous studies as well. Affiliation. Supported by the EMIL Network of Excellence.

P765 Up-regulation of the somatostatin receptor expression after irradiation in small cell lung cancer cells J. Oddstig1, P. Bernhardt1, O. Nilsson2, H. Ahlman3, E. Forssell-Aronsson1; 1 Department of Radiation Physics, Göteborg University, Göteborg, Sweden, 2 Department of Pathology, Göteborg University, Göteborg, Sweden, 3 Department of Surgery, Göteborg University, Göteborg, Sweden. Many neuroendocrine (NE) tumors overexpress somatostatin receptors (sstr), a fact that is utilised in tumor therapy using radiolabeled somatostatin analogues, such as 177Lu-DOTA-Tyr3octreotate. The somatostatin analogues bind to the sstrs in the plasma membrane, and some radiolabeled somatostatin analogs are internalized through receptor-mediated endocytosis. The sstr expression of different NE tumour cell lines can be up-regulated by hormones and growth factors, e.g. somatostatin, gastrin, estrogen or epidermal growth factor. There have also been indications of radiation induced up-regulation of the sstr expression on NE tumour cells. Such an up-regulation could be used to further improve the internalization of radionuclides. The development of methods that increase the number of receptors on tumor cells is important. The aim of this study was to investigate the possibility of inducing up-regulation of the sstr expression on tumor cells by irradiation. Methods: Human small cell lung cancer (SCLC) cells, NCI-H69, were irradiated by an X-ray tube using, 100 keV maximum photon energy, 8 mA current and a 1.7 mm Al filter corresponding to a mean energy of 48 keV, to absorbed doses of 28 Gy. The cellular binding and the uptake of 177Lu-DOTA-Tyr3-octreotate was measured 1-7 days after irradiation. The sstr2 mRNA expression was determined by quantitative reverse transcriptase-polymerase chain reaction (Q-PCR). Results: The binding and uptake of 177LuDOTA-Tyr3-octreotate was 1.5-3 times greater in cells irradiated to 4 Gy than in non-irradiated cells, and the highest uptake occurred 1 and 3-5 days after irradiation. The binding and uptake of 177 Lu-DOTA-Tyr3-octreotate was similar for cells irradiated to 2, 4, 6 and 8 Gy. The sstr2 mRNA expression was twice as high in the cells irradiated to 4 Gy than in the non-irradiated cells. Conclusions: The uptake of 177Lu-DOTA-Tyr3-octreotate increased in SCLC cells after exposure to irradiation, probably due to up-regulation of sstr expression. These results may be important in optimizing the treatment of tumors expressing sstr using radiolabeled somatostatin analogs.

P766 Influence of a diagnostic versus therapeutic dose of Lu-1773 DOTA-Tyr -octreotate on the uptake in somatostatin receptorpositive tumours and normal organs. B. F. Bernard, F. Forrer, M. Melis, W. H. Bakker, E. P. Krenning, M. de Jong; ErasmusMC, Rotterdam, The Netherlands. Aim: To investigate the influence of a diagnostic versus therapeutic dose on uptake in somatostatin receptor-positive tumours and normal organs.Materials and Methods: Tumour bearing (CA20948 pancreatic tumour) Lewis rats, were injected i.v. with different activities and different peptide masses of 177Lu-DOTA-Tyr3-octreotate: 3 MBq/0.5 µg, 3 MBq/15 µg, 300 MBq/15 µg and 555 MBq/15 µg. Biodistributions of subgroups (n=3) were obtained at several time points between 24 and 312 h. p.i.. The weight of tumours and organs was determined and the activity was measured in a gamma-counter. Ex-vivo autoradiographies with 177Lu-DOTATyr3-octreotate and after decay in-vitro autoradiographies with 111In-DOTA-Tyr3-octreotate of the same tumour slices were performed.Results: Healthy somatostatin receptor-positive tissue (pancreas, adrenals, pituitary and stomach) showed a significantly higher uptake (%injected activity/gram) with the low peptide mass, whereas the uptake in kidneys and muscle was identical, independent of mass and activity. In rats treated with 300 and 555 MBq a rapid decrease of tumour size was induced whereas the low activity did not influence tumour growth. Initially (24 h. p.i.) the activity concentration in the tumour was comparable in all groups. Over time we found an evident decrease in the activity concentration in the tumours of the rats injected with 3 MBq. In the rats injected with 300 or 555 MBq the activity concentration in the tumour remained constantly high while the tumor size in these animals decreased. Ex-vivo autoradiographies with 177Lu-DOTA-Tyr3-octreotate showed a significantly higher activity in the 300 and 555 MBq group compared to the 3 MBq groups. In contrast the in-vitro autoradiography with 111In-DOTA-Tyr3-octreotate in the same tumours revealed an inverse image, indicating lower expression of somatostatin receptors in the tumours that received a therapeutic amount, whereas the receptor expression in the other animals remained high.Conclusions: The present data indicate saturation of receptors in somatostatin receptor-positive tissues. Therapy with 300 and 555 MBq 177Lu-DOTA-Tyr3-octreotate induced a rapid tumour regression, resulting in constant, high activity concentrations in the tumours over time. In the diagnostic dose groups tumour size increased over time; the activity concentration in the tumours decreased. No saturation could be found in kidneys. The autoradiographies indicate a reduction of somatostatin receptor concentration in tumours during therapy.

S377

Poster Presentation

for animals given 177Lu-DOTA0-Tyr3-octreotate was reduced to 3 % of its initial value, 37 days after the injection. The treated tumours in both groups were fibrotic and with large confluent necroses. Conclusions 177Lu-DOTA0-Tyr3-octreotate seems to be more suitable than 177LuDOTA0-Tyr3-octreotide for receptor mediated radiation therapy of neuroendocrine tumours. High absorbed doses and good tumour response can be achieved.

P767

P769

Targeted radiotherapy of Gastrin-Releasing-Peptide (GRP) receptor expressing prostate cancer: therapeutic efficacy of 213 177 Bi vs. Lu labeled DOTA-PEG4-Bombesin (7-14) (DOTAPESIN)

Isotope selection for optimal tumor absorbed distributions for an in-vivo colorectal cancer model

D. Wild1, S. Good2, M. Frischknecht2, H. Zhang2, A. Morgenstern3, F. Bruchertseifer3, S. Kneifel1, J. Boisclair4, A. Provencher-Bolliger4, H. R. Mäcke2; 1Clinic and Institute of Nuclear Medicine, University Hospital Basel, Basel, Switzerland, 2Division of Radiological Chemistry, University Hospital Basel, Basel, Switzerland, 3Institute of Transuranium Elements, Karlsruhe, Germany, 4Novartis Pharma, SP&A/Investigative and Regulatory Pathology, Basel, Switzerland. Aim: The overexpression of GRP receptors in a variety of human carcinomas including prostate cancer provides an attractive target for internal radiotherapy. The goal of this study was to compare the therapeutic efficiency of 213Bi vs. 177Lu labeled DOTA-PESIN in PC-3 tumor bearing mice.Materials and Methods: DOTA-PESIN was labeled with 213Bi and 177Lu using a micro-wave heating. Biodistribution at different time points was carried out in human prostate cancer xenograft (PC-3 tumor) bearing nude mice. Afterwards the accumulated activity was calculated for various tissues in order to estimate the mean absorbed dose of both radionuclides. To assess the therapy efficiency of both radiopeptides PC-3 tumor bearing mice were injected with 3 x 6.67MBq 213Bi-DOTA-PESIN and 1 x 37MBq 177Lu-DOTA-PESIN. The tumor volume was measured using a caliper 3 times a week. The animals weight and behavior was assessed regularly.Results: The time between elution of the actinium-225/bismuth-213 generator and injection was 20 min. One hour after injection of 200pmol 213Bi-/177Lu-DOTA-PESIN the PC-3 tumor uptake was 9.0 ± 2.0 %IA/g and 11.6 ± 1.4 %IA/g respectively. At the same time the tumor-to-kidney ratio was 2.3 for 213Bi-DOTA-PESIN and 3.8 for 177Lu-DOTA-PESIN. The tumor volume at the time of injection (t = 0d) and therapy efficiency 18 days after injection (t = 18d) are shown in the table below. 177Lu-DOTA-PESIN only reduced tumor growth whereas 213 Bi-DOTA-PESIN reduced the tumor volume by more than 90%. The initial weight loss was about the same for both radiopeptides (213Bi-DOTA-PESIN: 2.1g and 177Lu-DOTA-PESIN: 1.7g). Finally, the dose deposition of 213Bi-DOTA-PESIN in the tumor was very high with 1.0Gy/MBq (177Lu-DOTA-PESIN: 0.53Gy/MBq).Conclusions: High specific tumor uptake and fast labeling of 213Bi-DOTA-PESIN enables high dose deposition of an alpha-emitting radionuclide in the PC-3 tumor. In addition, 213Bi labeled DOTA-PESIN is much more efficient than 177Lu-DOTA-PESIN in this human prostate cancer xenograft model with a tumor size up to 0.9cm.

tumor

control n=10 20MBq

213

Bi-DOTA-PESIN

n= 4 37MBq n= 4

177

Lu-DOTA-PESIN

volume

(mm3) tumor

volume

t = 0d

t = 18d

165 ± 60

1113 ± 210

166 ± 20

12 ± 3

173 ± 48

510 ± 36

(mm3)

P768 On the toxicity of gold - Au-198 nanoparticles as potential radioactive chemotherapaeuticals ? W. Brandau1, M. Tsoli2, H. Kuhn3, G. Schmid2; 1Universitätsklinikum Essen, Essen, Germany, 2Universität Essen, Anorganische Chemie, Essen, Germany, 3Universität Essen, Physikalische Chemie, Essen, Germany. Aim: The general aim of this study was to investigate by computational an experimental methods how biomoelcules e.g. DNA are influenced when they come into contact with inorganic nanostructured materials. Methods: Au55-Clusters with a diameter of exactly 1.4 nm have been synthesized, were incubated with DNA and high resolution TEM (transmission electron microscopy) was performed. Eleven different tumor cell lines have been incubated with these Au-Clusters and the viability of the cells has been determined at various timepoints. Control experiments have been performed using Cisplatin under identical conditions. In order to determine the subcellular distribution of the Goldclusters, cells were incubated and fractionated into membrane, cytosol, nucleus, and chromosomal DNA. The cell fractions have been irradiated with thermal neutrons in order to produce Au-198. After decay of short lived radionuclides the fractions were counted in a well counter and the % i.d were calculated for each fraction. Interactions between Au55 and DNAwere calculated by molecular mechanics and dynamics calculations. Results: Incubation of DNA with Au55-Clusters resulted in highly organized structures (“nanowires”) in the TEM images. Surprisingly no Au55 but only Au13-Clusters were found. Molecular modelling revealed that Au55-Clusters perfectly fit into the major groove of BDNA whereas Au13-Clusters fit into the major groove of A-DNA, which has been formed under the UHV (ultra highvacuum) conditions needed for TEM. In most of the tumor cells the toxicity of Au55 is significantly higher than that of Cisplatin (from 18-fold, U-2OS (osteosarcoma) up to 200-fold, MV3 (melanoma)). Cell fractionation followed by neutron activation revealed, that 57,5 % of the incorporated dose were associated to the membrane fraction, 42,5 % with the nuclear fraction and thereof 21 % were bound to the genomic DNA. Conclusions: In contrast to bigger elemental metallic nanoparticels (15 - 25 nm) Au55-Cluster with exactly 1.4 nm in diameter are extremely toxic. This toxicity combined with the radiation of Au-198 offers the possibility to develop new concepts for tumor therapy. Further experiments to evaluate this concept for other nanoparticles are currently under investigation.

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dose

P. L. Roberson1, D. J. Buchsbaum2; 1University of Michigan, Ann Arbor, MI, United States, 2University of Alabama at Birmingham, Birmingham, AL, United States. Aim. Spatial- and time-dependent heterogeneity of uptake is a well-known feature of radioimmunotherapy. The optimal choice of beta-emitting isotope depends on the uptake distribution and isotope properties (e.g. beta energies and physical half-life). We explore optimum isotope properties using activity distributions reconstructed in 3D and multiple times post-injection for an in-vivo colorectal cancer model. Materials and Methods. A total of 12 tumors with approximate masses of 0.1 g (~5mm diameter) and 0.5 g (~10mm diameter) and resected 1 h, 4 h and 24 h post antibody injection were chosen. Tumor activity distributions were reconstructed in 3D using serially sectioned LS174T tumors grown on the hind flank of athymic nude mice. Mice received an injection of either 177Lu-PA-DOTA-HuCC49 or 177Lu-PADOTA-HuCC49dCH2 anti-TAG-72 monoclonal antibody. These distributions were compared to idealized distributions representing uniform uptake and surface-enhanced (simulated necrotic core) uptake. Distributions were normalized to 100 uCi/g uptakes and convolved with dose point kernels for a selection of radioisotopes (Lu177, I131, Re186, Re188, and Y90). Compared were radial profiles for activity density and dose rate, mean dose rates, tumor central dose rates, and effective dose using a time integrated relative cell kill model. Isotope differences were studied by comparing estimated tumor to bone marrow doses for the two antibody models studied. Results. The activity density profiles show a more erratic pattern of uptake compared to idealized distributions. Improved central dose and loss of dose near tumor surfaces were observed for the higher beta energy emitters. Compared to idealized distributions with simulated necrotic core, the central dose for the larger tumors was higher for all isotopes. Conclusions. The simulated distributions were not representative of the large variation in uptake observed in tumors. There was generally better dose performance from the less penetrating isotopes. The dose distributions for the higher massed tumors were better represented by idealized tumors of smaller mass.

P770 211

At-labeled trastuzumab: evaluation of an alpha-particle emitting targeted radiotherapeutic for the treatment of breast carcinoma carcinomatous meningitis

A. Boskovitz, H. Ochiai, T. Okamura, G. Akabani, S. Carlin, D. D. Bigner, M. R. Zalutsky; Duke University Medical Center, Durham, NC, United States. Aim: Carcinomatous meningitis (CM) results from the dissemination of tumor cells into the subarachnoid space along the brain and spine. Systemic treatment with monoclonal antibody (mAb) trastuzumab is effective against HER2-positive systemic breast carcinoma but like other therapies, is ineffective against CM, to which many patients ultimately succumb. Astatine-211 emits Į-particles of high linear energy transfer and short range, which should be well matched to the disseminated, thin-sheeted nature of CM. The goal of this study was to evaluate the therapeutic effect of intrathecal administration of 211At-labeled trastuzumab in a rat model of breast carcinoma CM. Materials and Methods: Trastuzumab was labeled by reaction with Nsuccinimidyl 3-[211At]astatobenzoate (specific activity 40-80 MBq/mg). MCF-7 cells transfected to express HER2 cDNA (MCF-7/HER2-18) were studied. The cytotoxicity of 211At-trastuzumab for MCF-7/HER2-18 cells was evaluated by clonogenic assay and microdosimetric analysis. Athymic female rats were injected intrathecally with 1.25 × 107 HER2-transfected MCF7/HER2-18 cells through a previously surgically-implanted intrathecal catheter, which was used for treatment injection 3 days after tumor inoculation. In Experiment 1, animals were treated with 1.22 MBq (14 µg) or 2.44 MBq (14 µg) 211At-trastuzumab, cold trastuzumab (14 µg), or saline. In Experiment 2, animals inoculated with a 50% lower tumor burden were treated with 1.70 or 3.40 MBq 211At-trastuzumab, or saline. Animals were neurologically evaluated daily, and at the end of the study, their brain and spine were removed for histopathological analysis. Results: Reduction in survival to 37% (D37) of MCF-7/HER2-18 cells occurred at about 1 kBq/ml; microdosimetric calculations indicated an intrinsic cell sensitivity of 0.36 Gy. A preliminary study demonstrated that a 1-week infusion of 4 mg of trastuzumab beginning 3 days after tumor inoculation increased median survival by 57% from 21 days (saline) to 33 days. In Experiment 1, median survival was increased from 21 days when treated with saline or cold trastuzumab to 45 and 48 days when treated with 1.22 and 2.44 ȂǺq 211At-trastuzumab, respectively. In Experiment 2, median survival was increased from 23 days (saline) to 68 and 92 days for animals receiving 1.70 and 3.40 MBq 211At-trastuzumab, respectively. Differences in the percentage of animals with tumor and other histopathological changes at 6 positions along the brain and spine were observed among the treatment and control groups. Conclusions: We conclude that 211Attrastuzumab shows promise as a targeted radiotherapeutic for tumors overexpressing HER2, particularly those such as CM and ovarian carcinoma, which could be treated locoregionally.

P771 Molecular effect of auger electrons emitted by indium-111labeled antisense oligonucleotide on n-myc in human neuroblastoma cells N. Watanabe1, H. Sawai2, I. Ogihara-Umeda3, S. Tanada4, E. Kim5, Y. Sasaki4; 1International Atomic Energy Agency, Vienna, Austria, 2Gunma University Graduate School, Kiryu, Japan, 3Teikyo University, Sagamiko, Japan, 4National Institute of Radiological Sciences, Chiba, Japan, 5The University of Texas M.D. Anderson Cancer Center, Houston, TX, United States. Auger electrons can create breaks in nearby nucleic acids, giving them possible therapeutic utility. We investigated the therapeutic effect of Auger electrons emitted by indium-111 (111In)labeled phosphorothioate antisense oligonucleotides on human neuroblastoma cells in which Nmyc was overexpressed. Methods: Human SK-N-DZ neuroblastoma cells (5 × 106 cells) were