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Metastatic bone pain treatment with Samarium-153. Preliminary experience. M. Coronado, J. Coya, T. Navarro, R. Couto, G. Riesco, M.D. Marin, L.M. Martin-Curto. Department of Nuclear Medicine of La Paz University Hospital, Madrid, Spain. Pain asociated with metastatic bone disease is a clinical situation that contributes to patients’ morbidity and a reduced quality of life. Conventional palliative therapies are not always able to achieve pain relief. Objetive: the aim of the study is to evaluate the response to Samarium-153-Lexidronam of patients with painful bone metastatic disease. Methods: Twenty patients with painful bone metastases that did not had the expected respond to conventional therapies were included in the study. Mean age of 65 yers old (ranging from 36 to 85). Previous diagnosis included 11 prostate cancer (11 men), 8 breast cancer (1 man and 7 women) and a man with a carcinoma of unknown origen. All the patients had multiple lesions in the 99m Tc bone scintigraphy. Blood cell count showed a minimun level of 150000 platelets, 4000 white blood cells and an hemoglobine of 10 g/dl. Karnofsky performance status (KPS) was 40 or grater (range: 40-70). Pain evaluation scale (EVA) depending on the need for analgesic was recorded: 1) non-esteroidal anti-inflammatory drugs (NEAI); 2) non narcotic analgesics ± NEAI; 3) narcotic analgesics. Patient’s life expentancy was at least of four months. An intravenous injection of 37 MBq/Kg was administered in each treatment. Two patients received two doses. Evaluation of EVA and KPS as well as blood analysis were evaluated after treatment. Follow up was made for a medium of 8.4 months. Results: A total of 22 doses were administered. Subjetive improvement was found after 7-10 days of treatment in all the patients. KPS remained the same in 14 cases (65%), improved in 6 cases (25%) and worsened in two patients (one patient died and another is in preexitus status). EVA improved in 17 cases (75%) and remained stable in 4 cases (20%). No worsening was recorded. One case has been recently treated and follow up is not available yet. No signs of grade 4 marrow toxicity were found. Conclusions: In our experience, treatment with 153-Samarium is a safe and effective treatment for pain in patients with bone metastatic disease. Quality of life and pain relief is achieved in a high percentage of treated patients in whom other treatments were not effective.

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Automatic Reorientation of Myocardial SPECT Images, a new Methodology M.H. Farahani (1), A. Vakili (2), SH. Sadeghi (2). (1) Department of Biomedical Engineering of HTN Co , Tehran, Iran, (2) Department of Nuclear Medicine of Day General Hospital, Tehran, Iran. Aim: Our goal for this study is based on elimination of technician dependency to myocardial SPECT processing. Therefore this study has created a new automatic algorithm for heart long axis reorientation. Materials and Methods: The algorithm starts by finding approximately the cavity center of the myocardium using center of mass method. Then by using a search method based on an optimizing function we find the center of LV cavity in each cut of short axis views. The function value of each point depends on its activity and the minimal value of its circumferential profile curve. The selected set of consecutive points indicates an approximation of the LV long axis. These points are fitted by a straight line using the least square method and the whole 3D image is spatially rotated so this line become perpendicular to the short axis plane. The above procedure will be continued in an iterative manner until the value of the spatial angle alteration converges to a defined minimal threshold. Results: Automatic reorientation algorithm was respectively applied to 600 stress and rest study from 300 patients. The algorithm converged and was successful in all patients. This study eliminates the artifacts due to extra cardiac activities and severe defects. These studies were reoriented manually by four experienced technicians. The reproducibility of this method was perfect and much better than intraobserver and interobserver results. Also the correlation coefficient between our method and the operators average was more than all the values between each two operators. Conclusion: This automatic method is superior and will supersede manual reorientation for faster and more reliable processing of myocardial SPECT images. Considering the previous studies, in this method our findings appear to be more accurate and reliable

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The role of curve analysis as an alternative to Sincalide (CCK-8) in the prediction of gallbladder (GB) contraction. H.B. Semaan (2), A.J. Arroyo (1), G. Elias (2), L.S. Waldenberg (2), Y.P. Patel (1). (1) Department of Nuclear Medicine. St. Vincent Mercy Medical Center. Toledo, Ohio, USA., (2) Department of Radiology. The Medical College of Ohio (MCO). Toledo, Ohio, USA.. OBJECTIVE: Hepatobiliary imaging in the diagnosis of biliary disease is a well established technique. Tc-99m analogs have proven to be extremely useful for the evaluation of a wide variety of biliary disorders. The simplicity of the technique, the lack of morbidity or mortality, the augmentation of Morphine Sulfate (MS04) and/or Sincalide (CCK-8) to improve its sensitivity and specificity, and its diagnostic reliability have resulted in its rapid clinical application and acceptance. The purpose of our study was to evaluate a possible alternative to the use of CCK-8 to predict gallbladder (GB) function. METHODS: The data collected over the last 5 years were analyzed. A GB ROI was used to quantitate the ejection fraction (GBEF). The GB time activity curve (TAC) of the pre-CCK-8 data was analyzed by extrapolating the downslope (from max.), and utilizing this new fitted curve we predicted if the CCK-8 response would be normal or abnormal. These predictions were then compared to the actual CCK-8 GBEF results. RESULTS: Of the 1546 studies collected, 863 had CCK-8 infusions. 728 (84.4%) were excluded as they did not show any spontaneous GB contraction that would enable us to perform TAC extrapolation. Data analysis was performed on the remaining 135 patients. 39 cases incorrectly predicted as dyskinesia. 6 cases incorrectly predicted as normal. Of the remaining 90 cases, all were predicted correctly. 23 as dyskinesia, and 67 as normal responders. This corresponded to a sensitivity of 79%, specificity of 63%, PPV of 37% and a NPV of 92%. CONCLUSION: Our results showed that provided with a useful GB downslope TAC we were able to predict both normal and abnormal responses to CCK-8. This may allow us to extend the linical use of the stock at hand of the currently unavailable Sincalide.

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Comparison of Echocardiography with Planar Equilibrium Radionuclide angiography (ERNA) for the Assessment of Left Ventricular Ejection Fraction (LVEF) I. Paula, T. Coutinho, B. Barbosa, G. Costa, A. Bastos. Departement of Nuclear Medicine of the Instituto Português de Oncologia-Centro Norte, Porto, Portugal. Aim: Left ventricular ejection fraction (LVEF) are routinely measured to evaluate cardiotoxic effects of drugs applied during chemotherapeutic treatment. In our Institution, conventional ECG gated planar equilibrium radionuclide angiography (ERNA) is a common method to evaluate LVEF, nevertheless echocardiography is sometimes use, whenever is impossible to realize ERNA studies. The purpose of this study was to compare ERNA and echocardiography for the assessment of ventricular function in oncologic patients. Materials and Methods: Twenty two patients (4 lymphoma and 18 breast cancer), 1 men (62 years) and 21 women (median age: 61 years; range, 21 to 80 years), underwent echocardiography and ERNA. “In vivo” labelling red cells method, using Mallinckrodt sodium pyrophosphate kit followed by administrations of 666 MBq (18 mCi) of 99mTc-pertechnetate, was used for ERNA studies. Frame mode acquisition were preformed, in the best septal left anterior projection, to give 24 frames per R-R intervals and semiautomatic computer analysis were realized by technologists, using a SAGE Processing protocol (GE Medical Systems Group, Milwalkee, Wisconsin). Comparison between echocardiography and ERNA was done by linear regression. Results: The correlation between echocardiogram LVEF and ERNA LVEF was good (r=0.784). Linear regression analysis revealed LVEF(ECHO)=0.4935 LVEF(ERNA)+0.241. Conclusion: This study showed good correlation as well as agreement between echocardiography and ERNA in measuring LVEF.

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A Comparison Between Dipyridamole Versus Stress Myocardial Perfusion Imaging in Diabetic Patients D.R. Lakkireddy, R.A. Corpus, R.P. Ponto, C.Z. Dickinson. Dept. of Nuclear Cardiology, William Beaumont Hospital, Royal Oak, Michigan, USA. Background: Dipyridamole (DPY), a coronary artery vasodilator, is used to augment coronary artery blood flow in nonstenotic coronary vascular beds and enhance detection of hemodynamically significant coronary artery lesions. We hypothesize that due to the more severe and diffuse small vessel coronary artery disease (CAD) seen in diabetic patients, the ability of DPY perfusion imaging (DY-MPI) to detect hemodynamically significant CAD may be significantly reduced compared to exercise myocardial perfusion imaging (EX-MPI). Methods: Eighty-four diabetic patients admitted to our institution for symptoms of chest pain underwent myocardial perfusion imaging (MPI) by either DPY (N=45) or exercise (EX) (N=39) protocols followed by coronary angiography. Patients with prior coronary artery bypass, failure to achieve 85% predicted maximal heart rate by EX protocols, and/or poor quality images were excluded from this analysis. MPIs were analyzed with the Emory Cardiac Toolbox software package. Significant perfusion defects were defined as defects involving > 3% of the total myocardium. Each MPI was overread by two experienced readers. Coronary angiograms were reviewed by an experienced operator blinded to the clinical data. Comparisons were then made between defects detected on MPI and the actual coronary anatomy seen at angiography. Findings: Of the 45 diabetics undergoing DY-MPI, 13 had significant CAD but a normal MPI. Of the 39 patients undergoing EX-MPI, 3 had significant CAD but a normal MPI. The sensitivity of DY-MPI was much lower than EX-MPI (52% vs. 81%). Conclusions: This data suggest that in the diabetic patient, the ability of dipyridamole myocardial perfusion imaging to detect hemodynamically significant coronary artery disease is significantly reduced compared to exercise myocardial perfusion imaging.

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Pulmonary uptake of Tc-99m Sestamibi (MIBI)during myocardial perfusion testing: A comparison between smokers and non-smokers H.B. Semaan (2), A.J. Arroyo (1), T.R. Allen (1), P.C. Barman (1), L.S. Waldenberg (2), Y.P. Patel (1). (1) Department of Nuclear Medicine. St. Vincent Mercy Medical Center. Toledo, Ohio, USA., (2) Department of Radiology. The Medical College of Ohio (MCO). Toledo, Ohio, USA.. OBJECTIVE: Post-exercise pulmonary uptake of Thallium 201 is an index of left ventricular dysfunction and/or multivessel disease. More recent studies have also reported that post-exercise lung uptake of Tc-99m MIBI correlated with severe coronary artery disease (CAD) and reduced left ventricular function. The purpose of our study was to determine if a difference in pulmonary uptake of Tc-99m MIBI exists between smokers and non-smokers. METHODS: Resting and stress lung to heart ratios (LHR) were retrospectively determined in 144 patients who underwent Tc99m MIBI myocardial perfusion testing. 72 were non-smokers (4 males and 68 females, age range 30-86 yr., mean 64 yr.). A second group comprised of 72 smokers (32 males and 40 females, age range 37-83 yr., mean 60 yr.). Their respectively chest X-rays were reviewed. The LHR was determined by dividing the lung counts by the maximum myocardial counts using a 10 pixel rectangular ROI. Basic statistical analysis was performed using a 2-tailed Student’s t test and a p < .05 is taken to indicate a statistically significant result. RESULTS: Overall, the non-smoker group had higher lung uptake than the smoker group (p < .05). In both groups, those with positive results for CAD had higher lung uptake than those that were diagnosed as negative for CAD. This is in concordance with published results in the literature. Those patients determined to be positive for CAD, as well as those that were negative for CAD had consistently higher lung uptake in the non-smoker group when compared to the smoker group. This correlated well with chest X-ray findings of COPD. CONCLUSION: An increase in post exercise Tc-99m MIBI lung uptake is a marker of severe CAD. Our results confirm that this occurs in either non-smokers or smokers. In general our findings showed that lung uptake was significantly lower in the smoker group when compared to the non-smoker group, presumably due to less lung tissue available because of the damage caused by long term smoking.

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Do Beta-Blockers Affect the Extent & Severity of Perfusion Defects on Adenosine SPECT Myocardial Perfusion Scintigraphy?

Investigation of the effect of source distance and scattering medium on spatial resolution and contrast of gamma camera images

D.R. Lakkireddy, T. Bateman, I. McGhee, A. Joshi, R. Nerella, K. Moutray, M. Coen. Cardiovascular Consultants,The Mid America Heart Institute, Kansas City, Missouri, USA.

S. Sarkar (1), A. Abehesht (2), H. Firouzabadi (3). (1) Medical Physics Department of Tehran University of Medical Sciences, Tehran, Iran, (2) Azad Islamic University, Tehran, Iran, (3) Nuclear Medicine Department of Iran University, Tehran, Iran.

Background: Three prior studies have suggested that SPECT perfusion defect is reduced when a patient is retested on beta-blockers. It is not known whether this occurs with adenosine or whether adenosine SPECT perfusion on b-blockers will underestimate the presence, location or severity of the perfusion defects. We therefore analyzed perfusion defect site and extent in one hundred and fifty-eight patients, all of whom had completed coronary angiography and adenosine SPECT scintigraphy. Method: Of the total one hundred and fifty-eight patients who were included in the study, seventy six had their beta blocker therapy withheld (b-) for twenty-four to forty-eight hours prior to the test and eighty-two were tested while continuing on beta blocker therapy(b+). The groups were similar in age (65.0 years +/- 12.2 and 65.8 years +/- 12.4, Off and On betablockers respectively), sex and other anti ischemic medications. Patients with prior CABG, LVEF <40%, recent MI or PCI were excluded from this study. The SPECT variables analyzed were - Lung Uptake, TID, rest and stress Ejection Fraction, Sum Stress Score and location of perfusion defects. Stress variables were, rest and peak heat rate (HR), blood pressure (BP) and ST changes. Angiography criteria for CAD were W50% stenosis. Results: Patients tested on beta blockers had lower resting (p<.001) and peak (p<.001) heart rate, lower resting diastolic BP(p<.001), lower peak systolic BP(p<.001) and Diastolic BP(p.043), lower rest (p=.041) . Despite lower physiological variables there was no statistically significant difference in the Sum Stress Score and correct identification of the presence of 1, 2 or 3 vessel disease(p=ns) Conclusion: This study suggests that patients can be tested pharmacologically with adenosine on beta-blockers with no loss in either diagnostic accuracy or assessment of extent, severity or location of coronary artery disease.

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Aim: By identifying the effect of any parameter such as distance, attenuation, and scattering on the Line Spread Function ( LSF ), one can compensate the quantitative and qualitative destructive effect of such parameters by deconvolution method. Material and Methods: Using a 99mTc line source, this study was performed on a single head ADAC SPECT system operating in planar mode. Variations of FWHM and FWTM of the LSFs as a function of source to collimator distance in air, source depth in scattering medium (water) and the combined effects of distance and depth of the source in scattering medium were investigated. Results: The equations of spatial resolution (FWHM) with the above mentioned conditions were found to be R1= 0.0748l + 4.0862mm for 1100mm for and Rd = 0.0102d + 10.962mm for d 0mm and Rh = 0.2512h – 14.609mm for h100mm respectively. L and h are the source to collimator distances in air and scattering medium respectively and d is the source to collimator distance in the scattering medium eliminating distance effect on FWHM. These variations were found to be linear having different slopes. Conclusion: The results showed that increasing source to collimator distance in air degrades the spatial resolution considerably. That is an increase of 10cm degrades the spatial resolution by 54%. In this case the variation in FWTM is almost similar to FWHM. By increasing the source depth only in scattering medium ( eliminating the effect of source distance ) no noticeable change on spatial resolution is seen, but due to accumulation of scattered photons under both wings of the LSF, the increase in FWTM is more intense that FWHM. This phenomenon causes the broadening of sharp edges which in turn leads to loss of contrast and errors in determining the size of lesions and the uptake of activity in ROI.

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n TECHNOLOGISTS PART 1 Left ventricular ejection fraction calculated from ECG gated Tc-99m MIBI myocardial SPECT by 4D-MSPECT® software: correlation of physician and technologist F. Dede, Y. Narin, K. Gur, M. Ince, I.K. Budak, S. Orhan. Department of Nuclear Medicine of GATA Haydarpasa Military Hospital, Istanbul, Turkey. Aim: ECG Gated myocardial perfusion SPECT (g SPECT) has been used to calculate ejection fraction (EF), end-diastolic (EDV) / end-systolic volume (ESV) and correlated well with conventional methods. However, inter-observer variation between physician and technologist were rarely searched. We investigated the correlation between nuclear medicine physician and technologist for the assessment of EF calculated with 4D-MSPECT software program. Method: From 127 rest/stress Tc-99m MIBI gSPECT studies (54% men, 46 % women,) EF, EDV and ESV were calculated with 4D-MSPECT program by nuclear medicine physician and technologist. Results: Overall, there was a good correlation between physician and technologist (r: 0,9784 P<0,0001). Bland-Altman plots showed mean difference (± standard deviation [SD]) for EF of 0,094±2,1582%. The patients with large ventricular cavity (EDV>130 or ESV>65 ml) showed best correlation (r= 0,995, 0,990 respectively, P<0,0001). But patients with smaller ventricular cavity (EDV<55 or ESV<15 ml) also gave good results (r= 0,909, 0,882 respectively, P<0,0001). Sex difference or presence of perfusion abnormalities did not decrease the inter-observer correlation. Conclusion: 4D-MSPECT showed excellent correlation between physician and technologist for the calculation of EF. EF measurements calculated by technologist can be used interchangeably with that of nuclear medicine physician

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Quality works: evaluation in Myocardscintigrafi G.N. Nilsson, L.J. Johansson. Department of Nuclear Medicin of the Central Hospital of Karlstad Sweden. Aim: Prepare an education package for heart evaluation containing: Translation of the description for the processing software of Myocardscintigrafi adapted for Generel Electric workstation Genie into Swedish. Criteria how to choose angles and slices when the automatic software failures. Create a reference library on optical disk, for example: Difficult cases and stores them together with comments and instructions. Collect other cases with artefacts, for example movements, trigger artefacts, abdominal activity etc. Evaluate the impact of educational package. Material and Method: To evaluate the impact of the educational package we selected seven patients with irregular heart structure where the automatic software failures. We had six experienced technologists to reorient the heart for perfusion part in rest and stress protocol before and after the educational package. Myocardscintigrafi shows the perfusion of left ventricle. To construct the tomographic slice the technologist has to define two alignment axes parallel to the long axis of the left ventricle first in the transaxial plane (angle for vertical long axis VLA) and then in the oblique plane (angel for horizontal long axis HLA). Results: The variability of angle values in VLA and HLA between the different technologist decreased for all patients after the evaluation package. For one of the patient the variability of choosing alignment axes in HLA decreased from 30 % to 8% after the education package. Conclusions: The common criteria’s for evaluation have made the technologist to chose angles and slices more equal.

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N. Yoshida. Kainan Hospital, Yatomityou Maegasushinden Minamihonden 396 Amagu, Japan

L.J. Johansson. Department of Nuclear Medicine of Centralhospital of Karlstad, Sweden.

Aim: An optimized cut off frequency is ordinarily determined from a frequency band calculated closely to an actual LV volume in a phantom study by gated SPECT software package (QGS). It is difficult to diagnose by a heterogeneous image processed with this high cut off frequency. We compared with optimized cut off frequencies from a visual assessment by a normalized mean square error method (NMSE) and an actual LV volume. Materials and Methods: We separately included a solution of 99mTc, 201Tl and 123I in a cardiac phantom. A sequential investigated raw data was accumulated in a clinical collection time and these investigated SPECT images were reconstructed with various frequencies in a Butterworth filter. A sequential standard raw data was accumulated in ten times as large as a clinical collection time and a standard SPECT image was reconstructed with a ramp filter only. It was the optimized cut off frequency when a difference between the standard SPECT images and the investigated SPECT images was minimized. We altered a cut off frequency and determined a cut off frequency when a calculated phantom volume was nearly an actual phantom volume (175ml). Results: The nuclide distinction caused a difference between about 10% and 30% in an optimized cut off frequency calculated by a NMSE method. The calculated phantom volume by QGS was constant in a cut off frequency more than 0.45cycles/cm and an optimized cut off frequency by a NMSE method was lower between 15.5% and 37.8% as compared with QGS. Therefore, the calculated phantom volume by a NMSE method resulted in lower between about 7% and 20% as compared with QGS.

Aim: To investigate the relationship between measurements of left ventricular ejection fraction (LVEF) obtained using one automatic and one semiautomatic method. Material and Method: The material consisted of 33 patients who underwent a gated myocardial single photon emission computed tomography (SPECT) at stress (33) and at rest (15). Seventeen of the gated stress investigations were performed using a one-day protocol and a dose of 900 MBq technetium-99m-Tetrofosmine. The remaining investigations were performed using a two-day protocol and a dose of 600 MBq technetium-99m-Tetrofosmine in both rest and stress. Investigations with abdominal activity that influenced the endocardial border, were excluded. Two different methods, one automatic and one semiautomatic, were used to calculate LVEF in gated myocardial SPECT. Both methods have been developed by Germano and partners at Cedar Sinai Medical Centre, Los Angeles USA.The sampling parameters and the reconstruction, with the reorientation of the myocardium, was the same to both processing methods. The automatic method started with the full set of gated short-axis images. The centre of the left ventricle, the mid-myocardial surface and finally the endocardial border in systole and diastole were delineated automatically. The volume of the left ventricle was calculated from voxel volume and number of woxels in the cavity in all frames of the cardiac cycle. LVEF was derived from left ventricular cavity volumes at end-systole and end-diastole. The semiatomatic program used the same algorithm as the automatic method to assess LVEF, but it included a manual part to identify the left ventricule. A constraining limit around the LV was drawn manually in order to separate extracardiac activity from the myocardium. The apical and basal slice images were selected manually. The basal slice image was selected in the same way as in the bulls-eye plot. The apical slice was placed far out, as it almost is beyond the LV. The same experienced operator processed all 48 investigations. Result: LVEF ranged from 17 % to 82 % (mean 54 %). The LVEFs measurements obtained using the automatic method were on average 2.5 units greater than those obtained using the semiautomatic method. In 8 cases the automatically measured LVEFs were more than 5 units greater than the corresponding semiautomatic LVEFs. All of these 8 cases had an LVEF greater than 55%. Only in one case was the semiautomatic LVEF greater than the automatic LVEF. There was a high correlation between the two types of measurements (LVEF r=0.99;end-diastolic volumes r=1.00; end-systolic volumes r=1.00 Conclusion: LVEF measurements obtained with an automatic method were greater than those obtained using a semiautomatic method, especially for the patients with a high LVEF. This should be kept in mind when comparing results from investigations done with different method in the same patient.

An investigation of a cut off frequency by a quantitative gated SPECT software package: Comparison with a NMSE method

Cut off frequency (Volume) NMSE QGS

99m

Tc

0.38c/cm(151ml) 0.45c/cm(162ml)

Tl

I

201

123

0.28c/cm(113ml) 0.45c/cm(140ml)

0.31c/cm(129ml) 0.45c/cm(161ml)

Conclusion: It was concluded that we should determine respectively the cut off frequency for calculated cardiac functional quantities and the cut off frequency for a visual evaluation.

Greater LVEF measurements using an automatic compared to a semiautomatic method.

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Calculation of left ventricular ejection fraction (LVEF) in MUGA studies is both hardware, software and observer dependent. P. Christensen, R. Kurt, M. Hutchings. Dept. of Clinical Physiology and Nuclear Medicine, The Diagnostic Centre, Copenhagen University Hospital, Copenhagen, Denmark. Aim: To assess the dependency of LVEF measurements in MUGA studies on the type of camera, the software program for calculation, and the observer defining the ROIs. Patients and methods: In 20 patients referred for LVEF determination because of anthracycline chemotherapy MUGA studies were obtained both with a STARCAM (40 cm field-of-view) and a THYRUS camera (30 cm field-of-view). The STARCAM data were analysed with the GE eNTEGRA software system, the THYRUS data with the Pegasys and a locally developed program (Proview, Ledh-Moeller). Technologist interobserver variations were calculated both for the STARCAM data and the THYRUS data. Technologist intraobserver variations were calculated for the eNTEGRA data only. In our laboratory a change >0.10 EF units is considered a significant change during chemotherapy. Results (see table): No systematic differences were found between the two cameras. With the STARCAM only marginal interobserver variations were found. With the THYRUS data, one technologist produced slighthly higher LVEF values than the other one, independent of software. The intraobserver reproducibility with the eNTEGRA software was very high. Both technologists found slightly higher values applying the Pegasys compared to the Proview software. Conclusion: Although no significant systematic differences are found, LVEF determination with MUGA is frequently subject to considerable variations with different hardware and software. The inter- and intraobserver variations are very low with the eNTEGRA software, but notably larger with the Pegasys and Proview software.

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Activities that could be realiced by nurses in a Nuclear Medicine Department A. La Banda, M.D. Marin, M. Coronado, R.M. Espinosa. Department of Nuclear Medicine of The Universitary Hospital, Madrid, Spain. Aim: To establish other nurse tasks that can be assigned in the Nuclear Medicine Department Material and Methods: Protocols for nurses that can be developed: • Patients treated with I-131 (hyperthyroidism and thyroid carcinoma): questioning about social, labour and family situation, and patient information about radiation protection measures after the treatment. • Patients treated with Sr-89 and Sm-153 for bone pain: record of the patient Karnovsky performance status (KPS) and intensity of pain (EVA scale for need of analgesics). • Patients undergoing stress treadmill or farmacologyc stress (previous to myocardical perfusion SPECT): to aid the cardiologist during the stress test, control of vital constants, help with patient cardiac monitorization etc… Results: Durig one year (2001), the following nurse consultations have been realiced: 21 patients for treatment of bone pain. 280 patients with thyroid carcinoma treated with I-131. 159 patients with hyperthyroidism treated with I-131. 799 cardiologic patients. All the patients did a satisfaction survey after attending to the Nuclear Medicine Department. Conclusion: The previously described activities lead to make a nurse consultation, that can also be very helpful for instructing cardiologyc patients on their way of life and hygienic/sanitary measures.

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Renal maturation and response to furosemide H. Bultynck, F. Mannes, N. Van Roijen, L. Van Der Mauten, A. Piepsz, H.R. Ham. Department of Radioisotopes, CHU St Pierre, Brussels, Belgium. It has been suggested that an imperfect renal emptying during furosemide renography can simply be due to renal immaturity related to the age of the patient. Aim: to evaluate, in a population of hydronephrotic kidneys, the quality of response to furosemide in function of age. Material and methods: from a large database, 61 patients less than 1 year old were selected, 35 with unilateral and 26 with bilateral hydronephrosis (38 pelviureteric junction stenosis, 24 dilated vesicorenal reflux, 17 megaureters, 8 operated urethral valves with or without reflux). All these patients underwent a basic 20-min renogram followed by a 15-min furosemide challenge. Renal drainage was appreciated on a late postmicturition view obtained after change of patient’s position, and classified in good, partial or poor response to furosemide. Results: between 0 and 3 months of age, 5 out of 32 kidneys (16%) showed a partial or a poor response; between 3 and 6 months, 3 out of 31 kidneys (10%) showed the same pattern; between 6 and 12 months, 4 out of 23 kidneys (17%) showed the same pattern. Before one month of age, 3 out of 6 showed partial or poor response: they were all non-operated pelviureteric junction stenosis and at least in two of them the poor response to furosemide was unlikely due to renal maturation. Conclusion: the large majority of infants with hydronephrosis showed a good renal emptying after furosemide administration, whatever their age. There is presently no hard evidence that renal maturation plays a significant role in the impaired response to furosemide. __________________________________________________________________

Date: 01.09.2002 • Time: 16:30 - 18:00 • Hall: Poster exhibition TECHNOLOGISTS PART 2

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Experiences with a PET/CT-scanner in a PET-department E. Abramhamsson, R. Myschetzky. PET & Cyclotron Unit, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark. In December 2001, a new imaging modality, combined PET/CT-scanning was implemented in our department. The scanner, Discovery LS, is composed of a GE Light Speed Plus CT-scanner and a GE Advance PET scanner. The machine is constructed so that the two scans are performed in sequence on the same table. CT-slices are first completed as prescribed and the subsequent PET scan is then run at the same coordinates. The reconstructed CT data is used for attenuation correction of the PET data and as an anatomical map for PET tracer uptake. The two sets of images can be viewed independently or “fused.” Unlike conventional image coregistration systems the Discovery LS inherently guarantees that this fusion is exact, i.e. patient coordinates in the three planes are identical in the two scans. Only if the patient moves on the table during the scan will this be compromised. Due to the shortened scan time of less than 30 minutes this is a rare problem. We are in close contact with the Department of Oncology at our institution. Not only in examination reporting but also in treatment planning. DICOM communication makes it possible to transfer data to the Radiation Therapy Department’s treatment planning workstation where we have utilized CT in planning of IMRT (Intensity Modulated Radiotherapy Treatment) and brachytherapy. This is a great advantage for the patient and the health system in saved time and resources besides reduced radiation doses. To ensure the most precise positioning when the CT-scan is to be used in therapy planning, we have installed a separate alignment laser system. This new imaging modality, combined PET/CT, offers new opportunities in interdisciplinary collaboration, training and development for the staff in the department.

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R. Myschetzky, E. Abramhamsson. PET & Cyclotron Unit, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.

M. Hudournik, G. Smid, B. Poharc, M. Kac. Dep. of Nucl. Med., Hospital Celje, Celje, Slovenia.

Aim: F18-FDG PET examination time has been reduced by 50% with the advent of CT as a method for attaining attenuation correction files. This is achieved by positioning the patient supine with arms up over the head for thoracic, abdominal, and pelvic imaging (standard positioning in diagnostic CT scanning) thus allowing for a reduction in PET scan time without degradation in PET image statistics. Methods: A GE Discovery LS Plus PET/CT scanner is used to produce attenuation correction files necessary for PET imaging and as a radiological imaging tool. Due to the time difference between pin source transmission data and CT data for attenuation correction (2 min versus 21 min in a 7 FOV whole-body scan) we have found that patients can lay supine with arms up over the head and subsequently PET frame scan time can also be reduced from 5 min to 3 min. Results: Most patients, regardless of age, can lay supine with arms over the head for approximately 30 minutes without great discomfort given proper arm support. With this technique we have been able to produce PET and CT images without arm attenuation or artifacts in body imaging. When head and neck imaging is required, the patient’s arms are positioned alongside the body. If both head and body imaging is necessary, then the examination is performed as two separate studies with the patient’s arms as far out of the scan area of interest as possible. Conclusion: We have found that the new possibilities in scanning procedures available to us in combined PET/CT imaging have yielded diagnostically superior scans, reduced scanning time for patients, plus faster patient throughput utilizing scanner time and tracer optimally.

How to minimize contamination with Technegas

Aim: To introduce some measures to minimize the level of contamination with Technegas Material and methods: We perform ventilation scintigraphy with Technegas mostly before perfusion scintigraphy to determine the probability of pulmonary embolism. The Technegas generator with original accessories is used. At our nuclear medicine department average 150 ventilation studies wit Technegas are made per year. Results: We developed and applicated some protection measures to minimize contamination with Technegas. Inhaling of Technegas is performed in separate room away from gamma camera to avoid contamination of gamma camera through exhaled Technegas. This room is used only for this purpose. It´s recomended to have an air conditioning system with filters. Technicians wear lead aprons and rubber gloves. They put on also paper coats, caps and masks. The course of examination is explained to the patient. It must be stressed on how important is to close mouth around the mouth piece. It is very important that patient exercises with breathing system without Technegas first. A nose-clip must be put on the lover part of the patient´s nose and checked to prevent leakage through nose completely. When the inhalation of Technegas is completed, the patient has to be asked to continue with breathing into closed system for a while. After inhalation patient and technicians leave the room. Tubes, mouthpiece, gloves, paper masks, caps and coats are put into lead container. Conclusion: This measures turned out to be beneficial in our daily practice.

P_18

P_20

P.J.M. Kok, J.E. v Eerd, F.H. Corstens, W.J. Oyen. Department of Nuclear Medicine, University Medical Center St. Radboud, Nijmegen, Netherlands.

E.K. Kekilli (1), B.T.B. Bilge Turk (2), C.Y. Cengiz (1), O.M.A. Omer Murat (1), S.K. Sedat (1), M.C. Mehmet (2). (1) Department of Nuclear Medicine of the Inonu University, Malatya, Turkey, (2) Department of Plastic and Reconstructive Surgery of the Inonu University, Malatya, Turkey.

Differences in uptake and kinetics between tumor and infection in rats

Objectives:The aim of this study was to investigate the dynamic distribution of 18FDG in malignant and inflammatory lesions. Methods:LS174T colon carcinoma cells and E.coli bacteria were injected s.c. in 29 rnu rats 2 weeks (left front leg) and 1 day (right front leg) before 18 FDG injection, respectively. In 24 rats, biodistribution was determined by counting dissected tissues at 1,2,3 and 4 hours after injection of 11 MBq 18FDG. In 5 rats, dynamic FDG-PET (Siemens Ecat Art) was performed (27 frames of 6-15 min) for 4 hours after injection of 15 MBq 18FDG. The maximum and mean FDG uptake (Bq/cc) was calculated and plotted by using a ROI centered over the 2 lesions. Means ± SEM were calculated. Results:FDG accumulated in the tumor and infection up to 1.13±0.10% ID/g and 0.80±0.04%ID/g at 1 hour, respectively and remained constant until 4 hours for both lesions. There were no significant differences in wash out between the 2 lesions. The tumor/blood and infect/blood ratio increased with time to 57±17 and 48±14, respectively. Dynamic PET imaging visualized both lesions. The ROI data derived from the images showed a higher and faster FDG uptake in the infection but there were no differences in wash out. FDG uptake in the tumor reached a maximum of 60 ±12 KBq/cc at 60 minutes and in the infection a maximum of 100±6 KBq/cc at 45 minutes, both remaining constant. Conclusion:Although in this model there were differences in absolute FDG uptake between tumor and infection, there was no indication of different focal FDG kinetics over time. There was no indication that FDG uptake in cells involved in acute infection was temporary as compared to FDG uptake in malignant cells, indicating that dual time point imaging does not necessarily resolve diagnostic pitfalls for FDG-PET in oncology.

Decontamination of human skin from 99mTc-pertechnetate.

The most important aspect of skin function is the maintenance of a water impermeable barrier towards the environment. Such a barrier function also provides protection from enviromental chemical hazards. Aim of our study was compaired efficiencies of washing with soap, liquid soap, neutral chirurgical soap and (1%) DTPA for skin 99mTc-pertechnetate decontamination. These studies were made on human abdominal skin samples, recovered after plastic surgery. Soap, liquid soap, neutral chirurgical soap and (1%) DTPA were obtained DURU inc (Istanbul-Turkey), Colgate-palmolive Inc (Hacisakir liquid soap, Istanbul-Turkey), Merkez ilac san and tic. AS (Isosol antiseptic sol, Istanbul-Turkey) and Amersham International (UK). The skin epidermal surface was contaminated with 20 mCi/500ml 99mTc-pertechnetate (2 cm depth) for 2 min. 3 min later, the skin was divided four piece. One of them was washed three times with soap or liquid soap or neutral chirurgical soap or (1%) DTPA for 1 min. Split thickness skin grefts were obtained with electrically dermatom and countered with gamma probe and dose calibrator. The efficiencies of washing with soap, liquid soap, neutral chirurgical soap and (1%) DTPA are compared. Skin 99mTc-pertechnetate decontamination rate with soap, liquid soap, neutral chirurgical soap and (1%) DTPA were obtained % 66, % 65, %43 and %47. 30 minute later, Subepidermal activity rate was obtained % 7 in not washed area. Our results were exposed that decontamination efficiencies of soap and liquid soap are same and better than neutral chirurgical soap and (1%) DTPA.

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PET/CT: A significant improvement in scanning efficiency

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The effects of Profile attenuation correction on myocardial perfusion SPECT: A phantom study M. Ince (1), K. Gur (1), M. Deger (2), F. Dede (1), Y. Narin (1). (1) Department of Nuclear Medicine of GATA Haydarpasa Military Hospital, Istanbul, Turkey, (2) Department of Nuclear Medicine of Marmara University Hospital, Istanbul, Turkey. Aim: In this study, we investigated the effects of Profile attenuation correction on lesion detectability and volume calculation from Tc-99m and Tl-201 myocardial perfusion SPECT. Method: Two transmural cold defects were located at mid-septal (D1; 2x2x1 cm) and proximal lateral (D2; 2x3x1 cm) walls. Heart, both lungs and body of phantom were filled with 250 µCi, 80 µCi, and 1,5 mCi Tc-99m or Tl-201 and water mixture respectively. For the suitability of clinical practice, the routine acquisition parameters were used. The data from cardiac phantom were acquired with 64 projection views over 180° extending from 45° right anterior oblique to 45° left posterior oblique with dual detector gamma camera (Siemens e.cam Plus® & Profile attenuation correction) for high-resolution (HRES) and ultra-high-resolution (UHR) collimators. Images were reconstructed with (AC) and without attenuation correction (nonAC) for Tc-99m and Tl-201. Lesion contrast (C) and noise (N) values were calculated from short axis images and the cardiac volumes (V) were computed by 4D-MSPECT software (original cardiac volume: 61 ml). Results: The results of this study were as fallows, Tc-99m HRES UHR Tl-201 HRES

nonAC AC nonAC AC

C (D1) 24,62 35,37 31,59 46,71

C (D2) 34,36 49,89 43,69 63,35

V (ml) 58 61 56 62

N 5,7 6,4 6,1 6,8

nonAC AC

20,33 29,27

27,98 40,74

52 61

5,2 5,4

P_23

Comparative study between 99m Tc-DMSA renal scan, intravenous urogram and voiding cystourethrograms in 114 children with ITU in diagnosis of acute pyelonephritis. E. Gil, C. Ponce, I. Acevedo, C. Calvo, T. Cambil, J. Castro, B. Rodriguez de Quesada. Department of Nuclear Medicine of the Universitary Hospital, Seville, Spain.. This study compares 99mTc-DMSA renal scan with intravenous urogram and voiding cystourethrogram, that are used in diagnosis of pyelonephritis in children with urinary tract infection (ITU). MATERIALS AND METHODS: The study includes 114 patients ( 44 males and 70 females) with suspected of urinary tract infection. Age range was 1 month-15 years. Diagnosis methods employed were 99mTc-DMSA renal scan, intravenous urogram and voiding cystourethrogram. 3 hours afetr intravenous injection of 99mTc-DMSA, a renal scan was performed with a gammacamera, using pinhole collimator (posterior and posterior obliques images) and a parallel hole collimator (posterior and anterior images). RESULTS: From 114 patients studied, we obtained diagnosis of pyelonephritis in 64 cases and it was negative in 50 cases. Sensitivity was 90 %, specificity was 95%. Intravenous urogram: Sens: 30 % Spec: 91 %. Voiding cystouretrhogram: Sen: 30 % Spec: 90 %. CONCLUSIONS: 99mTc-DMSA renal scan results were better than results of intravenous urogram and voiding cystouretrhogram, in diagnosis of pyelonephfitis in children with urinary tract infection.

Conclusion: For Tc-99m, contrast values calculated from AC images showed 45% improvement in both collimators compared with non-AC images. For Tl-201 this improvement was about 44%. In the volume determination, AC images gave more accurate values. However, attenuation correction minimally increased the noise for both radionuclides. Although Profile attenuation correction slightly increased the noise, it gave better results for image contrast and volume calculation.

P_22

Kidney Depth and Determination of Relative Renal Function K. Nilsson. Department of Nuclear Medicine, University Hospital, Linköping, Sweden. Aim: To obtain reference values for relative renal function using a technique not including or estimating kidney depth. Material: From our consecutive referred adult patients a reference group was picked with normal renal function (camera based clearance of MAG3), and without diabetes, treated hypertension, hydronephrosis or uptake defects in the renal parenchyma. Additional requirements were no abnormal location of the kidneys (upper border of one kidney below the midpoint of the other) or asymmetry in kidney size (less than 10% difference calculated as kidney surface area in the posterior projection). The selected material consisted of 86 patients with an age range 21 – 79 years. Methods: Renography was performed with MAG3 with the patients in supine position. Ten second frames were acquired for 16 - 20 minutes in a matrix of 128*128 pixels on a GE XRT gamma camera and a Starcam 3000 computer. Before start of acquisition the patients were asked to lift their back from the camera table a couple of times. By this manoeuvre, that increases intra-abdominal pressure, the kidneys are moving in a cranial direction and forced backwards to be located in their most dorsal position, thereby minimising a side difference in kidney-to-skin distance. Perirenal ROIs were used for background subtraction and the split function was calculated with both the integral method and the double corrected slope method (Rutland-Patlak plot) according to the formula dx% = dx/dx+sin (Semin nucl med 1999;29:146-59.). The reproducibility of relative renal function determination with this technique is about 2%. Results: Mean dx% Range Integral method 49,3 44-54 Slope method 50,3 46-54 Conclusion: The results show that there is a very narrow range of relative renal function in normal kidneys without measuring kidney depth. Hence correction for kidney depth does not seem to be necessary when using the proposed renographic technique.

P_24

A simplified visual method for quantification of Brain Perfusion Spect. M. Serrano, C. Silva, A. Serena, J.M. Nogueiras, I. Vale, J. Outomuro, L. Campos. Department of Nuclear Medicine. Hospital do Meixoeiro, Vigo, Spain. Several complex and manufacturer specific programs has been proposed for quantitative analysis of Brain Perfusion but none has achieved a general acceptance. Aim: To describe and validate a simplified semiquantitative “visual” method of quantification of Brain Perfusion SPECT. Methods: A 99mTc-Brain Perfusion SPECT (HMPAO; 925 MBq) was performed in 25 consecutive patients with ischemic stroke within 24h. of symtoms onset. Acquisition: doubleheaded SOPHA-DST tomocamera (64x64 matrix, zoom x2, 64: 20 –fast- to 40 sec. steps; LEUHR collimators); reconstruction: Shepp-Logan Modified filtered back-projection. Scintigraphic indices were correlated with initial neurologic scores and with stroke volume calculated by planimetry on a CT diagnostic scan performed on 3 - 7 days after admission. Quantitative Indices: a) Count-based indices: 24 consecutive transaxial slices from the most caudal fronto-occipital one excluding cerebellus to vertex were selected on the carefully reorientated tomographic dataset. A dynamic dataset and a composite image were generated and two rectangular mirrored ROIs placed over each hemisphere. Original count-activity curves, differential (normal minus involved), ratio (normal/abnormal) and respective area under curves (AuC) were calculated. Three numerical indices were evaluated: Average asymmetry index: {(AuC ratio) / 24 } – 1. % Hemispheric counts deficit: { (differential counts)/(normal hemispheric counts)} * 100 Equivalent (virtual) “zero-perfusion” cortical volume loss: (total differential counts)/ (cts. in representative cortical pixel) The (maximum) counts in a representative cortical pixel is determined by the x-intercept of the extrapolated linear fit applied to the down-sloping portion of the cortical histogram (Mountz & Infeld). b) Semiquantitative visual scores: Infarct size and severity were visually assessed by means of a ten steps percentual LUT. Added individual scores in 22 areas (deficit graded 1 to 4 vs. contralateral side in each area; subcortical regions weighted by a x2 to x3 factor) gave a Total Weighted Score; spatial extent was given by the number of areas involved. Results: Pearson correlation coefficients between counts-based indices were r: >0,961 and with visual scores r: >0,719. Scintigraphic visual scores correlated slightly better with neuro-

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n TECHNOLOGISTS PART 2 logical scales r: >-0,505 to -0,667 than the numerical ones. Visual scores (r: 0,569, r: 0,682) and count-based indices (r: >0,751) both correlated reasonably well with CT based infarct volume. Conclusion: These simplified and easily calculated visual scores could be a realistic and interchangeable indices for estimation of infarct volume and severity.

P_26

The Effect of Ritalin on Dopamine Balance in Children with ADHD F.P.J.M. Coenjaerts (1), I.H.A. Al Younis (1), M.J.P.G. van Kroonenburgh (1), J.S.H. Vles (2). (1) Department of Nuclear Medicine, University Hospital of Maastricht, The Netherlands, (2) Department of Neurology, University Hospital of Maastricht, The Netherlands. Aim: Children with attention deficit hyperactivity disorder (ADHD) are known to have disturbed central dopaminergic transmission. In this research, the central dopamine pathway was studied before and after Ritalin treatment by using 123I-IBZM (post-synaptic D2 receptor ligand) and 123I-FP-CIT (dopamine transporters radionuclide) produced by Amersham Healthcare. Materials and Methods: Six children (age range: 6-9 years) with de novo ADHD were studied before and after 3 months of treatment with Ritalin at a dose of 5 mg t.d.s. A total activitiy of 110 MBq 123I-IBZM was administered intravenously and brain SPECT images were taken 2 hours p.i.. Several days later, 110 MBq 123I-FP-CIT was injected i.v. and SPECT images were performed 3 hours p.i.. One patient did not come back for 123I-IBZM after Ritalin. Images were obtained using a triple-headed gamma camera (Siemens) using fanbeam collimator. Total time of acquisition was 30 minutes (45 seconds per frame for 40 views per detector). Zoom factor used was 1.23 and the matrix size was 128 x 128. Filtered back-projection acquisition was performed. Images were filtered using Butterworth clinical filter with a cut-off value of: 0.5-0.6 and an order of: 0.4-0.5. The reconstructed images were compared visually before and after treatment with Ritalin. Futhermore, quantification ratios were measured using the striatum/occipital cortex for 123I-IBZM and putamen/occipital cortex and caudate nucleus/occipital cortex in case of 123I-FP-CIT. The occipital cortex represents the non-specific binding. Ratios were calculated for both sides. Results: The following ratios were measured: IBZM FP-CIT before after before after Striat. Striat. Caud. Putam. Caud. Putam. Caud. Putam. Caud. Putam. left right left right left right left right left right left right 4.31 3.8 13.47 11.86 16.67 11.07 6.00 5.60 5.70 4.10 3.83 3.96 4.02 4.60 9.28 11.57 10.98 10.52 3.56 4.49 4.30 4.62 4.84 5.05 3.82 3.27 11.50 14.10 17.00 15.80 4.14 4.02 4.34 3.84 4.52 4.12 3.77 4.17 13.06 14.25 13.50 15.09 4.72 4.44 5.18 5.23 4.57 3.81 2.60 3.30 12.36 12.06 14.25 11.85 7.19 7.34 5.53 5.89 4.57 4.63 3.84 3.22 10.47 11.22 11.96 11.07 7.55 8.67 6.95 7.97 This table shows that the post-synaptic dopamine binding of 123I-IBZM is not changed significantly after three month treatment with Ritalin (the P value for the left side is 0.068 and for the right side 0.250). On the other hand, there was a significant reduction in the striatal dopamine transporters after treatment with Ritalin (the P value for the left and right putamen is 0.002 and for the left and right caudate nucleus is 0.001). Conclusion: Our study showed that the effect of Ritalin on the dopamine transporters is superior to it’s effect on the post-synaptic dopamine uptake.

Reproducibility of measurements of dopamine transporter (DAT) density by SPECT with 123-I Altropane S.A. Barrow, A.A. Bonab, B.K. Madras, A.J. Fischman. Division of Nuclear Medicine, Massachusetts General Hospital, Boston MA, USA. Aim: Altropane (E isomer of 123-I -2 beta - carbomethoxy-3 beta-(4-fluorophenyl)-N-(1iodoprop-1-en-3-yl)nortropane) has been demonstrated to be a highly selective SPECT ligand for quantifying dopamine transporter (DAT) density in patients with Parkinson’s disease and attention deficit hyperactivity disorder (ADHD). Since an important application of this radiopharmaceutical will be in evaluating disease progression and effects of interventions in longitudinal studies, test-retest variability of DAT measurements is of great importance. Materials and Methods: In the present investigation, two measurements of DAT density were performed approximately 3 weeks apart in four healthy Rhesus monkeys. Each animal was positioned prone on the imaging bed of a dual headed SPECT camera (Siemens MS2) equipped with fan-beam collimators. Head immobilization was performed using a custom fabricated head holder. Approximately 5 mCi of 123-I Altropane was injected i.v. over 1.0 min. and dynamic SPECT images were acquired over 90 min. Images were collected in 2 min. acquisitions during the first hour and in 5.0 min. acquisitions thereafter. The images were reconstructed using a conventional filtered back-projection algorithm and attenuation correction was performed by the Chang method. Regions of interest were constructed over the striatum (caudate nucleus + putamen) and occipital cortex (reference region) and the resulting time-activity data were analyzed by the reference region linear graphical method developed for reversible receptor ligands to calculate distribution volume ratio (DVR) for the striatum. Results: In all studies 123-I Altropane accumulated in the striatum rapidly, reached a maximum by 10-15 min. after injection and approached background levels by the end of the study. Tracer accumulation in occipital cortex was lower and decreased much more rapidly. DVR plots for striatum using occipital cortex as the reference region were linear by ~10 min. after injection and asymptotic slopes were calculated from the data acquired between 10 and 70 min. Average values for DVR for the repeat studies were remarkably similar; 1.58+/-0.16 and 1.57+/-0.12 respectively (t=-0.25, p=0.98, NS). Conclusion: These results clearly demonstrate that measurements of DAT density by SPECT with 123-I Altropane have a very high degree of test-retest reproducibility. This finding clearly supports the utility of this radiopharmaceutical for longitudinal studies of disease progression and monitoring the effects of therapeutic interventions.

P_27

Low bone mineral density after renal transplantation. R.M. Álvarez (1), J. Toro (2), R. García (3), M. González (4), A. Gentil (5), J. López (6), A. Gutiérrez (7), P. Gómez (8), R. Vázquez (9). (1) D.U. Nuclear Medicine of H.H.U.U. Virgen del Rocío, Seville, Spain., (2) Departament of Nephrology of H.H.U.U. Virgen del Rocío, Seville, Spain., (3) D.U. Nuclear Medicine of H.H.U.U. Virgen del Rocío, Seville, Spain., (4) D.U. Nuclear Medicine of H.H.U.U. Virgen del Rocío, Seville, Spain. Object: The aim of our study was to evaluate bone mineral density (BMD) in patients with bone pain after renal transplantation. Methods: In this cross-sectional study, the prevalence of bone disease was investigated in renal transplanted patients, who had undergone renal transplantation in the period 1984-2001. Clinical an biochemical markers ( sex, weight, age, race, menopause age , time after transplantation, PTH, vitamin D, nutricional stage) were collected. Bone scans were done on each subject for femoral neck and lumbar spine using dual-energy X ray absorptiometry (DEXA) Hologic QDR 4500W. Results: Eighty one renal transplanted patients were studied ( 24 male, 25 premenopausal female and 32 postmenopausal female), aged 30-73 years (mean 50 year). Our results showed that there was statistically significant difference in bone mineral density between three groups (p<0.05).A significant correlation was found between premenopausal female BMD and poor nutritional stage ( p< 0,02 ) using ANOVA test. Not statistically differences was found with the other parameters. We have found a significant correlation between time after transplantation and osteoporosis in these locations in postmenopausal group p< 0,05. Lumbar spine Tscore Normal osteopenia Male 83,3% 16,7% Pre menopausal 68% 20% Post menopausal 37,5% 28,1%

osteoporosis 0%

Femoral neck Tscore Normal osteopenia osteoporosis 83,3% 16,7% 0%

12%

65,4%

19,2%

15,4%

34,4%

45,5%

36,4%

18,2%

Conclusion: The prevalence of osteoporosis is considerably higher in females than in male postransplantation patients and higher than in the general population. Between pre and postmenopausal female we have not found statistically differences. The high prevalence of osteoporosis in premenopausal female was associated with poor nutritional stage and in postmenopausal female with time after transplantation.

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M.R. Soto García, D. Fuster, I. Mendo, E. Romero, M. Tantull, P. Jordano, P. Sanz, E. Colomer, D. Rodríguez. Department of Nuclear Medicine, Clinic Hospital, Barcelona, Spain.

S. Halders (1), D. Janssen (1), F.M.H. van Dielen (2), G. Kemerink (1), G.A.K. Heidendal (1), J.W.M. Greve (2). (1) Department of Nuclear Medicine, Academic Hospital Maastricht, (2) Department of General Surgery, Academic Hospital Maastricht, The Netherlands.

Present situation of the Bone Scintigraphy in the Complex Regional Pain Syndrome

Bone scintigraphy is a functional study of bone tissue, it is used in the diagnosis and evolution of the complex regional pain syndrome (CRPS). The CRPS is definided as a polymorph painful syndrome due to vasomotories alterations of neurovegetative origin that upset the mycrocirculation of one articular region, affecting superiors and inferiors extremities with distal prevalence. The aim of this study was to evaluate our experience (casuistry) in those patients refers to Nuclear Medicine Service which showed clinicals symptoms suggesting CRPS, to perform a bone scintigraphy. Methods: 76 patients (29M, 47F, age range 19-84, mean age 55) who suffered CRPS. Bone scintigraphy was performed after injecting 25 mCi Tc99mMDP and taking immediate blood pool and static images after 2 hours by a single head gammacamera. We chose the following data of epidemiologists and clinics interests: age, sex, department, possible cause of CRPS, extremity affected and bone scintigraphy findings. Results: The results showed: Department: reumatology 25, traumatology 18, rehabilitation 18, pain treatment unit 11, others services 11. Possible cause of CRPS: Mechanical pain 29, surgery 15, trauma 14, systemic disease 12, other causes 6. Extremity affected: superior 37 and inferior 39. 31 patients were positive CRPS: 18 F (age range 50-84, mean age 61) and 13 M (age range 19-82, mean age 46). In the following table is indicated in percentage the extremity in both sexes: Positive CRPS Female Male Superior Left 6% 6% Extremity Right 72% 23% Inferior Left 11% 46% Extremity Right 11% 23% Conclusions: Bone scintigraphy is useful in the diagnostic of CRPS. In patient with CRPS, we may conclude that: a) in female the extremity more affected is the right superior extremity in 72% and male the left inferior extremity in 46%; b) frecuency of disease in female, the % is higher in surgery 33% and trauma 33%, respect to the male in which mechanical pain is the most frequent cause 44%, thus we can determinate that female could do more functionals overexertions.

P_29

Radiosynovectomy of knee with 90Y colloid and 99Tc colloid albumin L. Belloni (1), G. Bigi (1), P. Sangalli (1), D. Serafini (1), D. Salvo (1), F. Rossi (2). (1) Dpt of Nucleare Medicine of the ASMN of Reggio Emilia, Italy, (2) Dpt of Rheumathology of the ASMN of Reggio Emilia, Italy. AIM: In this job we will describe our experience as regards 90Y therapy for treatment of knee’s synovial pathologies. PATIENTS and METHODS: Our Group follows this methodology strictly cooperating with rheumatology Group. Patients subject to this treatment are between 18 and 80 years old. They have to suffer from an active chronic synovitis (at least 6 months’ disease), which responds neither to systemic way treatments (FANS/DMARDS) nor to intra articular ones (steroids). The surgery we introduced, after arthrocentesis, 7 MBq a TC99 colloid albumin, followed by 185 MBq of Y90.After this, we inject some cortisone watered down with physiologically solution in order to optimise diffusion of Y90 in each part of knee’s synovial cavity. After bandaging we get orthogonal images (front and side) on gamma camera, to prove procedure’s accuracy. RESULTS: Feedback to treatment as regards inflammatory pathologies (rheumatoid arthritis) are really positive: after one-year result is satisfactory. Concerning arthrosic pathologies, the period for an eventual relapse is reducing to 2/3 months. CONCLUSION: The use of TC99 colloid albumin makes us check procedure’s accuracy and lets us have documents of legal value which show inject of Y90 into synovial cavity: in fact wrong introduction of Y90 into cavity would imply local necrosis of involved tissues.

Gastric emptying rate, before and after gastric restrictive surgery, in morbid obese patients.

Aim: Morbid obesity is a life threatening disease in Western society. A treatment modality for morbid obesity is gastric restrictive surgery. In our hospital two types of gastric restructive surgery are performed: the vertical banded gastroplasty (VBG) and the LapBand operation. Little is known about gastric emptying after both types of operation. The aim was to study the effect of VGB and LapBand operation on gastric emptying rate, both before, and 1 year after operation. Material and methods: In total 33 patients were included in this study, 14 patients underwent VBG, and 19 patients underwent LapBand operation. Preoperative as well as 1 year postoperative, gastric emptying rate was measured. To this end, all fasting patients received a semi liquid, high caloric (303 kcal per 74 g), test meal (Oral impact Novartis nutrition), to which 37 MBq 99mTc-hepatate was added. After this test meal, gastric emptying rate was measured for 2 hours, using a one headed Siemens gamma camera. The following parameters were evaluated: the lagfase (time between finishing eating and the start of the stomach emptying), the T-50 (time between the start of the stomach emptying and 50% emptying), the exponential emptying rate and the stomach activity after 30, 60 and 90 minutes. Results: In table 1 , the P-values of the difference between preoperative and postoperative data for both types of operation are depicted. The Wilcoxon signed rank test was used for statistical analysis. A P-value <0.05 was denoted significant. Table 1 Type of Lagfase T-50 operation VBG 0.3378 0.3395 LapBand 0.9115 0.9395 *Stoma = stomach activity

Exponential emptying 0.0205 0.2629

Stoma * 30 min. 0.5081 0.7813

Stoma * 60 min. 0.0717 0.5215

Stoma * 90 min. 0.0638 0.5431

Conclusion: In this study we demonstrated a significant increase (P < 0.05) in exponential gastric emptying rate after VBG, whereas after LapBand operation no significant increase was observed.

Date: 01.09.2002 • Time: 16:30 - 18:00 • Hall: Poster exhibition TECHNOLOGISTS PART 3

P_31

Utility of posterior oblique views in Tc-99m DMSA renal scintigraphy F. Mannes, H. Bultynck, N. Van Roijen, L. Van Der Mauten, A. Piepsz, H.R. Ham. Department of Radioisotopes, CHU St Pierre, Brussels, Belgium. Introduction: Tc-99m DMSA is now widely accepted as procedure of choice for the diagnosis of acute pyelonephritis in children. Procedures guidelines suggest that optimal test should include right and left posterior oblique views in addition of posterior image. However, in a small number of restless children it is sometimes difficult to get three good quality images. Aim: to evaluate the utility of posterior oblique views in Tc-99m DMSA renal scintigraphy Methods: Three nuclear medicine specialists were asked to report 40 Tc-99m DMSA renal scans using posterior projection only. One week later, they were asked to reinterpret the same scintigraphies using the posterior and the right and left posterior oblique views. They were also asked, for each kidney, to determine whether they considered the oblique views helpful for reporting. Results: Were oblique views useful? Yes Somewhat No

Observers 1 2 4 4 5 4 71 72

3 5 7 68

Changes in report 1 2 1 0 2 0 2 0

3 2 1 6

Conclusion: Oblique views were found useful in only a small number of cases and did not significantly modify the reporting. Therefore, in case of restless children, all efforts should be concentrated in obtaining a good posterior view, even at the price of not having oblique posterior projections.

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n TECHNOLOGISTS PART 3 Labeling of leukocytes with 5 ml whole blood : is it feasible ? B. Georges, L. Van Der Mauten, N. Van Roijen, H. Bultynck, F. Mannes, A. Piepsz, H.R. Ham. Department of Radioisotopes, CHU St Pierre, Brussels, Belgium. Introduction: A fifty-ml whole blood sample is generally used for labeling leukocytes. This amount is sometimes difficult to obtain in clinical practice, particularly in young children. Aim: to investigate if a 5 ml whole blood sample was enough to label white blood cells (WBC) with 99mTc-HMPAO. Material and methods: The investigation was done on 30 adult patients. A first 50 ml whole blood sample was used for the standard labeling protocol. A second 5 ml whole blood sample was taken at the same time and the same labeling protocol was used, except that cell-free plasma was replaced by 0.9% saline.

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Evaluation of Segmented Attenuation Correction Method for FDGPET studies: Comparison of Conventional Method K. Matsumoto (1), S. Sakamoto (1), Y. Wada (2), H. Mori (2), M. Shinoda (1), M. Senda (1). (1) Institute of Biomedical Research and Innovation, Kobe, Japan, (2) Siemens-Asahi Medical Technologies Ltd.,Tokyo, Japan.

Conclusion: A good labeling efficiency was obtained with 5 ml whole blood. Preliminary clinical studies on 3 children, using a 10 ml whole blood sample, provided satisfactory results.

Objective: Both segmented attenuation correction (SAC) method and post injection transmission scan are useful and widespread in clinical whole-body FDG-PET studies. SAC method usually does smoothing in transmission data, this calculation segments a u-map into three degree of attenuation coefficient. This method is used for reducing transmission scan time without deteriorating quality of PET images. However, SAC method has a tendency to underestimate attenuation coefficient, resulting lower delectability for lung field lesions. Method: In this phantom study, we evaluated quantitative accuracy of SAC method using transmission scan and emission scan data. A dedicated 3D PET scanner, CTI EXACT ECAT HR+, was used to scan images of two types phantoms, a spherical phantom (Japan Radioisotope Association phantom) and a cylindrical phantom (20 cm diameter). We evaluated differences between transmission images (u map) of SAC method and measured attenuation correction (MAC) method, and those two types of attenuation corrected emission data (emission + SAC method, emission + MAC method) and emission data only (without attenuation correction). Results: In transmission data, recovery coefficient (RC) values at 10 mm diameter in MAC method, SAC method of spherical hot area were 0.27, 0.00 respectively. In emission data, emission + SAC method and emission + MAC method showed almost same RC values in every size of hot area diameter. Conclusion: In pulmonary mass lesions, it is necessary to correct partial volume effect in quantitative PET measurement. However, from our data, SAC method is not appropriate for partial volume effect correction.

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Results: Whole blood sample WBC activity

Labeling efficiency

min Max Mean SD

50 ml 202 MBq 430 MBq 309 MBq 59 MBq 41.2 %

5 ml 74 MBq 223 MBq 132 MBq 45 MBq 19.1 %

Caudal tilt; its effect on gated equilibrium blood pool studies. M. Farmer, I. Jones. Nuclear Medicine Service, Southern Derbyshire Acute Hospitals NHS Trust, Derby, UK. Left ventricular ejection fraction (LVEF) is a useful predictor of long-term prognosis and short-term risk. Gated Blood Pool LVEF is routinely used at this centre as one of the selection criteria prior to treatment with angiotensin-converting enzyme (ACE) inhibitors as suggested by the SAFE study and for chemotherapy appraisal. The installation of a dual headed gamma camera without the ability to apply caudal tilt required establishment of any possible difference in LVEF acquired with and without caudal tilt. Caudal tilt is generally applied to help improve LA and LV separation. Standard in-vivo labeling of approximately 750 MBq of 99mTc and r-r gating were applied. A parallel whole medium sensitivity collimator was used in acquiring the 45 LAO view, but adjusted for best separation of the RV from the LV. Consecutive acquisition with and without 10 caudal tilt of the detector head (towards the feet) for LVEF was then performed. All studies were successfully processed using a semi- automatic algorithm, (n=40). The correlation between LVEFs measured with and without caudal tilt was high, r=0.92, indicating that either method may be used. It has been suggested that the variation between serial studies should be less than 5%; any difference greater than this deemed clinically unacceptable. The Bland–Altman comparison of two methods of measurement set the limits of agreement for the data at 5.99% above and –6.89% below the calculated mean difference. Which suggests therefore the two methods should not be used interchangeably. It also indicates that the theoretical reduction in LVEF from the overlying end diastolic LA is probably not the main cause of the differences between the two data sets and is most likely the result of various affects.

Mapping of Function and Anatomy with a new kind of hybrid cameras: New options in nuclear medicine diagnostic A. Pfeiffer, H. Bihl. Department of Nuclear Medicine, Klinikum Stuttgart, Katharinenhospital, Stuttgart, Germany. Aim: The lack of detailed anatomic information in nuclear medicine imaging is often felt as a drawback, especially when 131I, 111In-Octreotide and 18F-FDG are used in tumor detection. A new generation of hybrid cameras offers the necessary components to acquire simultaneously anatomic and functional data in one examination. Mapping of anatomic and functional information can now be realized without any further effort by the user. Method and possibilities of image presentation of function together with anatomy will be demonstrated in selected clinical settings. Methods: Functional data in SPECT or coincidence technique are acquired on a hybrid camera (GE Millennium Hawkeye). Thereafter, an axial x-ray-transmission-scan is performed in the emission scanned volume with the same camera. Both datasets are reconstructed with identical matrix size and identical slice thickness. To map the dataset, the anatomic slices are overlied to the functional slices as a transparency. The level of transparency determines the contribution of the anatomic information in the mapped picture. All these procedures can be carried out with the camera software. If it will be possible to export the slices into a standard PC data format, standard software as Adobe Photoshop or Corel Photopaint can be used, too. Results: In view of the new technical developments of the GE Millennium Hawkeye, we can demonstrate that image fusion results in considerable localization benefits of functional findings, especially in thorax and abdomen. Care should be taken when x-ray based attenuation correction is applied: metallic implants may generate false positive results. Conclusion: The hardware based image mapping with the Hawkeye camera allows an exact assignment of hot spots to anatomic data and thus increases the significance of nuclear medicine imaging. It is conceivable that the value of software based image mapping will decrease. Double examinations won’t be necessary in the near future as functional and anatomic information will be acquired in one step.

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Poster Presentation

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H. Otake (1), T. Higuchi (2), Y. Takeuchi (3), H. Ryuo (3), M. Jimbo (3), K. Matsubara (1), I. Koyama (1), N. Oriuchi (2), K. Endo (2). (1) Division of Diagnostic Radiology of Gunma University Hospital, (2) Department of Nuclear Medicine of Gunma University Hospital, (3) Anzai Medical CORP´, Gunma, Japan.

K. Matsumoto (1), S. Yamamoto (2), K. Tarutani (2), S. Sakamoto (1), M. Shinoda (1), H. Iida (3), H. Watabe (3), M. Senda (1). (1) Institute of Biomedical Research and Innovation, Kobe, Japan, (2) Kobe City College of Technology, Kobe, Japan, (3) National Cardiovascular Center, Suita, Japan.

Aim: New compact type semiconductor gamma camera (eZ-SCOPE AN) using Cadmium Zinc Telluride (CdZnTe) as a detector has been developred mainly for the clinical evaluation of superficial organs or for application in the field of navigation surgery. In this study, basic characteristics of this machine has been evaluated. Material and Methods: Detector of this compact gamma camera has 256 semiconductors representing same numbers of pixels. Each of semiconductor sized 2 X 2 mm is located in 16 lines and 16 rows in parallel on the surface of the detector. In this study the specific performance characteristics was evaluated referring to NEMA standards shown as below. Intrinsic energy resolution, intrinsic count rate performance, integral uniformity, system planar sensitivity, system special resolution, and also the signal to noise (S/N) ratio between two neighboring pixels. Results: The intrinsic energy resolution measured as FWHM was 5.7%. The intrinsic count rate performance ranging from 17 kcps to 1,285 kcps was evaluated, but the highest intrinsic count rate was not observed. Twenty percent of count loss was recognized at 1,021 kcps. With the high sensitivity collimator, the integral uniformity was 1.3 %. The system planar sensitivity was 33,330 cpm / MBq of high resolution collimator and 766,767 cpm / MBq of high sensitivity collimator. The system spacial resolution (FWHM) was 2.0 mm when the distance between the source and the collimator was 0 cm and it was 2.2 mm when the distance was 3 cm. Conclusion: The new compact gamma camera showed high sensitivity, high resolution and superior intrinsic count rate. Future application for clinical use is thought to be promising.

Objectives: To measure cerebral blood flow with O-15 PET, it is necessary to measure the time course of arterial blood radioactivity. We examined the performance of three different types of continuous blood sampling system. Methods: Three kinds of continuous blood sampling system were used: a plastic scintillatorbased beta detector (conventional beta detector, (BETA))[1], a bismuth germanate (BGO)based coincidence gamma detector (Pico-count flow-through detector, (COINC))[2] and a phoswich detector (PD)[3] composed by a combination of plastic scintillator and BGO scintillator. Performance of these systems was evaluated for absolute sensitivity, count rate characteristic, sensitivity to background gamma photons, and reproducibility for nylon tube geometry. Results: The absolute sensitivity of the PD was 0.212 cps/Bq for Ga-68 positrons at the center of the detector. This was approximately three times higher than BATA, two times higher than COINC. The value measured with BETA was stable, even when background radioactivity was increased. The count rate characteristic of the PD and COINC was linear up to 8 kcps. The reproducibility of sensitivity for nylon tube geometry of COINC was the smallest (C.V. = 1%) among the three. PD was the weights the least (3.5 kg) among the three, which is convenient for clinical use. Conclusions: Each detector has unique characteristics derived from its own structure. Although the performance of all three detectors meets clinical requirement, PD had the highest physical performance. Reference: [1] Hutchins GD, et al. A continuous flow input function detector for blood flow studies in positron emission tomography. IEEE Trans Nucl Sci. Vol.33, 546-549. 1986. [2] John RV, et al. Performance evaluation of the Pico-Count Flow Through detector for cerebral blood flow PET studies. J Nucl Med. Vol.39, 509-515. 1998. [3] Yamamoto S, et al. Development of a Phoswich detector for a continuous blood sampling system. IEEE Trans Nucl Sci. Vol.48, 1408-1411. 2001.

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R.H.A. Koopmans, S.C.M. Balen van, B.G. Hoving, F. Buijs, E.J.F. Franssen, G. Luurtsema, R. Boellaard, A.A. Lammertsma. PET centre of the VU University Medical Centre of Amsterdam, The Netherlands.

H.N.J.M. Greuter, G. Luurtsema, R. Boellaard, P.L.B. van Ophemert, E.J.F. Franssen, A.A. Lammertsma. PET Centre, VU University Medical Centre, Amsterdam, The Netherlands.

Evaluation of efficiency of a semiconductor gamma camera( eZSCOPE AN)

Use of a gas delivery system (GDS) for O-15 gas studies

Introduction: As no commercial equipment was available, a gas delivery system (GDS) for administering 15O bolus gasses was developed: 15O2 for studying regional cerebral metabolic rate of oxygen and C15O for cerebral blood volume. The purpose of the present study was to test this new GDS for ease of use in routine clinical studies. Methods: The GDS is connected directly to the 15O cyclotron and is positioned next to the PET scanner. It consists of a dose calibrator in which a closed perspex tube is placed, with inside a balloon for collecting the 15O gasses. Several tubes and valves are connected to the GDS, which all are operated electronically under remote control: (1) a tube from cyclotron to balloon with a valve just before the balloon; (2) a tube and valve from the balloon to the patient’s nasal oxygen cannula; (3) a tube and valve from balloon to waste and; (4) a tube and valve from injector to perspex tube. Before filling the balloon with 15O gas it is completely emptied (in the waste direction) by forcing 200 ml air into the perspex tube. After this initialisation procedure 15O gas is collected in the balloon. When the maximum dose of 15O gas and a minimum volume of 75 ml are reached all valves are closed. Administration starts when dose has decayed to 3,0 GBq for 15O2 and 2,0 GBq for C15O. Patient administration is performed using the same procedure as during initialisation, except that valves are switched in such a way that 15O gas within the balloon is directed to the patient’s nasal oxygen cannula. The patient is then asked to inhale through the nose. An extractor hood, placed over the face of the patient, collects exhaled 15O gas, which is directed to waste. Conclusions: The GDS is a user-friendly system that can be operated under remote control. With the GDS and appropriate breathing instructions approximately 10% of the 15O dose reaches the brain, indicating that gasses are administered efficiently.

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Performance Evaluation of Continuous blood sampling system for PET study: Comparison of three detector-systems

On the measurements of 15O blood concentrations

Introduction: In a newly developed method for measuring regional cerebral blood flow, oxygen metabolism and blood volume, multiple arterial blood samples are withdrawn in addition to continuous on-line sampling: 3 samples after bolus injection of H215O, 3 samples after bolus gas administration of C15O and 6 samples after bolus gas administration of 15O2. During production of C15O and 15O2 using an RDS111 (CTI, Knoxville, USA) cyclotron, trace amounts of 11C impurities are formed (<0.5% at time of administration). These impurities are insignificant at the time of scanning, but may result in inaccurate determination of blood and plasma concentrations due to the progressive delay in processing this number of samples. The purpose of the present study was to measure blood and plasma 15O concentrations accurately, even in the presence of trace amounts of 11C. Method: A Wallac Wizard 1480 Wellcounter (Wallac, Turku, Finland) was prepared for counting 15O samples. The counter was programmed to count samples using an energy window without decay correction. Whole blood and plasma samples were prepared, weighted and counted as soon after withdrawal as possible. After one hour, samples were recounted to measure possible 11C contamination. A spreadsheet program was written, in which all values for weights, counts, and counting, withdrawal and delay times (for both counting periods) could be entered. This resulted in 15O blood and plasma concentrations, which were corrected for 11C contamination. The 11C blood concentrations were also used to verify that 11C contamination was negligible during the actual scanning periods. Conclusion: Use of a sensitive wellcounter allows for the measurement of 11CO impurities in blood samples following administration of 15O blood and plasma concentrations can be determined, even if there is a backlog due to the number of samples to be processed.

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Reproducibility of quantitative analysis of DaTSCAN in a brain phantom S.M. Lansbergen, A.L. Spijkerboer, C.M. de Bruin, B.L.F. van Eck-Smit, J. Booij. Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. Several parkinsonian syndromes are characterised by loss of striatal dopamine transporters. For SPECT imaging of these transporters, DaTSCAN ([123-I]FP-CIT) is nowadays routinely used to evaluate parkinsonian syndromes. For interpretation of DaTSCAN brain images, quantitative assessment of striatal tracer uptake is important, especially for serial imaging of parkinsonian patients. Before introducing DaTSCAN on a department of nuclear medicine, quantification of striatal dopamine transporters can be tested with a brain phantom with known activity distributions. Aim: To determine the reproducibility of quantitative analysis of DaTSCAN using a phantom. Materials and Methods: To simulate three different clinical situations, the Alderson striatal phantom (obtained from Radiology Support Devices, Long Beach, CA, USA) was filled with 30 kBq/ml and 40 kBq/ml 123-I for the right and left striatum, respectively, and 5, 10, or 15 kBq/ml as background activity. For acquisition, a Siemens three-headed SPECT camera (MS3) with Nuclear Diagnostic processing system as well as a brain-dedicated SPECT System (Strichmann 810x) were used, using standard acquisition protocols. On the MS3 camera, acquisition was performed with a LEHR and Fanbeam collimator. For all collimated systems, the phantom was repositioned and acquired three times for each activity distribution. Moreover, to test phantom-based differences, the phantom was refilled 3 times with each abovementioned activities. To assess inter- and intra-observer variability, each study was analyzed by three operators and three times by one operator. Regions of interest with a fixed shape and size were placed on the striatum and in the occipital area (representing background uptake) at 4 different transversal slices showing the most intense striatal binding. Mean ratios of striatal to occipital uptake were calculated from these four slices. Variability was calculated as the absolute values of the test/retest difference expressed as the percentage of the mean of the test/retest measures. Results: The mean intra-observer variability was very low (< 0.8%) for each collimated system. The mean inter-observer variability ranged from 0.8-1.1%, reaching the highest variability for the Strichmann system. Repositioning of the phantom resulted in variability in the ratios (range 2.2 ± 1.3 – 2.7 ± 1.1%; mean ± SD), showing no clear difference between systems. As expected, refill of the phantom resulted in the highest variability: 2.9 ± 1.6%, 4,6 ±1.4%, 7.1 ± 1.4% for the LEHR- , Fanbeam-collimated and Strichmann system, respectively. Conclusion: The Alderson brain phantom seems useful to study variability of quantitative measurements of DaTSCAN.

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Evaluation as a tool in the education of technologists. W. Heegaard. Department of Clinical Physiology and Nuclear Medicine, Vejle Hospital, 7100 Vejle, Denmark. Aim: Better education More individuality More satisfied students Better possibility of attachment of students Currently all of us need to attract students to nuclear medicine, and to keep them attached to us. Therefore it is necessary to optimise the education, and evaluation is a tool to accomplish this. Methods: During the first week of the practical education in the department, we start with a conversation with the student about his or her expectations. Half through the study period we make an evaluation based on a standard form (see figure). Moreover, we discuss what we have written down at the start of the period, and we address things that should be corrected. At the end of the period we make a final evaluation to see whether the goals have been reached for the period. All of the three evaluations must be bilateral. Conclusion: After introduction of the regular evaluations, the standard forms, and the conversations based thereon we have: Experienced that the students express increased satisfaction of having more influence on their educational courses. Obtained useful information about the students, especially as to how they learn, i.e. whether they learn by listening, or reading, or by doing the practical things before they read about them? What are strong and weak points of their knowledge? And we discuss how to handle things properly and to make things better. Experienced an increased motivation along with the students` increased influence on their education and following satisfaction. They are more satisfied with their study period, and it is our impression that their education has improved. Got more variation in the job as teachers, and hence also more satisfaction. This will also indirectly benefit the students Generally obtained a better, equal, and straightforward communication with the students. Standard form: Name of student: ____________________ Above average Knowlegde

Average

Below average

Technical knowlegde Use of technical knowlegde Problemsolution

Skills

Love of order

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Breadth of view

Thick crystal digital Gamma Camera vs thin crystal analogical Gamma Camera:performance evaluation using different radioisotopes R.L. Lucianini, M.M. Menzaghi, C.L. Ceriani, G.S. Garancini, B.I. Butti. Department of Nuclear Medicine of the Hospital of Circolo,Varese,Italy.

Practical work

General performance Independence Attitudes

Responsibility Interpersonal skills Motivation Contact with patients

Using the standard form as a set point, it is easier to perform the evaluation. It also makes it more “legal” for the student to give feedback to the teacher and the department.

Poster Presentation

AIM: The deep knowledge of the technical characteristics of own hospital department apparatuses is important in order to plan the best use of them and to optimize diagnostic performances.We compared two Double-Head Gamma Cameras produced by the same manufacturer but with different characteristics. The first has an analogical electronic and a thin scintillator crystal (3/8”) while the other one is equipped with a totally digital electronic and a thick crystal (5/8”) and can also execute coincidence PET acquisition as well as the most traditional utilization. METHOD: We used three γ rays emitting radionuclides with different energy levels photons: 99mTc (a low energy level emitter), 67Ga (a medium energy level emitter) and 131I (a medium-high energy level emitter). We considered three technical properties in order to evaluate the apparatus performances: % energy resolution, intrinsic and system sensitivity and intrinsic and system spatial resolution. RESULT: Many significant differences are showed. Intrinsic parameters data reflects our expectations: for very low energy levels (< 100 KeV) the Thin Crystal Gamma Camera reach the better performances but the other one (thick crystal device) is superior as well as the energy rise. Different are the results for system performances: experimental values confirm those theoretical only for extreme energies, thus low and medium-high energy (<100 KeV, >200 Kev), while for the 99mTc energy level theoretical expectations are minimized by collimation factor. CONCLUSION: The use of the apparatuses is consequently more flexible than theoretically expected on traditional exams, both having good performances with tracers labeled with 99mTc. The Gamma Camera with thick crystal has a sensitivity gain given by the digital system that correct the loss of sensibility caused by crystal. For the exams utilizing others radioisotopes we keep the theoretical assumptions: we must use the thin crystal GammaCamera for the low energy tracers (example 201Tl) while the thick crystal apparatus gives the best performances for medium-high energies (example 67Ga and 131I).

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M.D. Turowska (1), D. Turowski (2), A. Stasiak-Barmuta (3), J. Wysocka (2), F. Rogowski (1). (1) Department of Nuclear Medicine, Medical University, Bialystok, Poland, (2) Department of Pediatric Laboratory Diagnostics, Medical University, Bialystok, Poland, (3) Department of Flow Cytometry, Children’s Hospital, Bialystok, Poland.

J. Dolezal, J. Vizda. Department of Nuclear Medicine, University Hospital, Hradec Kralove, Czech republic.

Transient increase in recently activated T cells after 131I treatment of patients with Graves’ disease

Aim: The aim of study was the examination of the effects of radioiodine treatment on peripheral blood (PB) T cell activation in patients with Graves’ disease. Methods: The study was carried out in a group of 32 patients with Graves’ disease (24f; 8m) 52,3±8,9 years of age treated with 131I (average dose 505,0±113,0 MBq). The percentage of the recently activated peripheral blood lymphocytes characterized by simultaneous expression of the CD45RA and CD45RO antigens on CD4+ and CD8+ cells separately and HLA-DR antigen on CD3+ cells were assessed by three- or two-color flow cytometric analysis (Coulter Epics XL) before, six weeks and six months after radioiodine treatment. Results were given as median and quartiles (p25-p75) values. A Wilcoxon’s rank sum test was performed to compare the data. Statistical significance was set at p<0,05. Results: Percentage of the CD3+HLA-DR+ lymphocytes slightly but significantly increased six weeks after 131I treatment in comparison to initial evaluation: 5,3(3,6-7,4)% vs. 3,9(2,5–6,8)%, p<0,05, and tended to persist at similar level 6 month after treatment compared to second evaluation: 5,1(2,7–7,3)%, p=0,5496. The difference between third and initial values also didn’t have statistical significance: p=0,1422. More significant alterations were observed in CD4+ and CD8+ subsets separately concerning to CD45RA and CD45RO antigens expression. In CD4+CD45RA+CD45RO+ subset transient significant increase of the percentage was observed 6 weeks after 131I treatment in comparison to initial evaluation: 9,5(3,9–13,8)% vs. 1,2(0,2–4,3)%, p<0,00005. 6 months after 131I treatment respective parameter significantly decreased compared to 6th week evaluation: 1,8(1,1-4,3)%, p<0,00005, and approached to initial values: p=0,2557. Percentage of the CD8+CD45RA+CD45RO+ subset also significantly increased 6 weeks after 131 I treatment in comparison to initial evaluation: 15,6(11,1–23,1)% vs. 1,8(0,2–9,9)%, p<0,00002, and then significantly decreased in 6 month after treatment compared to second evaluation: 6,3(3,0–11,2)%, p<0,00004, but was still significantly elevated in relation to initial value: p<0,002. Conclusions: The changes in recently activated PB T-cells caused by 131I treatment in patients with Graves’ disease confirm involvement of cellular immunity after radiation damage of thyroid gland and could contribute to deviation of immune response leading to development of the ophtalmopathy.

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Clinical role of Thyroglobulin and WB-131I scan in follow-up of Differentiated Thyroid Carcinoma: a retrospective study on 722 patients L. Pedrazzini, M. Andruccioli, L. Colombo. Department of Nuclear Medicine Ospedale di Circolo-Busto Arsizio (VA) Italy. AIM: The aim of this study was to evaluate retrospectively the role of Tg and WB131I scan on prediction relapse of disease, after withdrawal thyroxine therapy. METHODS: We selected 722 consecutive pts.in stage M0 (istotype: 626 papillary, 96 follicular) treated with radioiodine in the period 1990-1998 with follow-up ≥ 3 yrs. (136 males, 586 females, mean age 44±14,73 yrs.; range 13-81 yrs.). Diagnostic WB scan and Tg was performed 6-8 months after ablation of remnant, annually in the first 5 yrs., and then once 3 yrs. Sensivity of Tg was 0,2 ng/ml (commercial kit of Dia Sorin Italy) and of antibodies anti-Tg was 5 UI/ml (commercial kit of Bio-Rad France). RESULTS: 611 pts. presented at 6-8 months and during the follow-up, Tg V5 ng/ml, antiTgV100 U/ml, WB-scan negative. 53 pts. presented at 6-8 months Tg>5 ng/ml, or anti-Tg >100 and performed 1-4 radioiodine treatment (40 persistent remnants, 11 suspect mediastinic or cervical lymph-nodes, 2 persistent elevation of Tg). Among the variables considered only subtotal thyroidectomy’s incidence was quite different in patients treated (31,1%) and ablated (3,9%). It was impossible to demonstrate relapse of disease in 15 pts. whose Tg > 5ng/ml at the end of follow-up. 58 pts. (15 pts. only ablated) presented metastases. Tg or anti-Tg predicted relapse of disease in 52 pts. at 6-8 months; of these pts.25 had positive WB scan, and 33 pts.had diagnosis of relapse by citology in 21, by Tc in 4, by WB-99mTc-MIBI in 6, by echography in 1, by adenectomy in 1. Treatment of metastases was performed by surgery in 38 pts., by radioteraphy in 1, by 131I in 9. In 6 pts. Tg V5 and anti-Tg V100 the diagnosis of metastases was performed by FNAB in 4, by WB scan in 1, by WB scan and echography in 1 (Tg always indosable: false negative). Percentual difference in the mean age (47±18,3; median 49,5 vs.43,7±14,4; median: 43) and in stage T4 (43,1% vs. 17,5%) was observed between group with metastases and group without metastases. CONCLUSION: Group of pts. ablated after total thyroidectomy, age <45 yrs., stage different on T4, Tg V5 ng/ml, anti-TgV100, WB scan negative at 6-8 months, should be considered at very low risk of relapse. Further ablation of persistent remnant appears unnecessary, and the follow-up may be made with annual clinical control, echography of the neck, dosage of Tg and anti-Tg by intramuscular administration of recombinant-TSH.

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Radionuclide palliative therapy with Samarium-153-EDTMP in patients with bone metastases and refractory bone pain

Aim: Bone metastases appear in some patients with malignant tumorous disease even if they undergo the all therapy. The breast cancer and the prostate cancer are considered as the most frequently occured metastatic tumors in bones. The bone pain appears in majority of patients with metastases. This kind of pain considerably impairs the patient´s life, mobility and also has a negative effect on his psychic. One possibility how to reduce or to remove this pain is the administration of the radiotherapy to the place of metastases and also the irritation of periost. The present medicine dispose of two ways how to administer radiotherapy in the place of metastases: externally irradiation or intravenous administration of bone-seeking therapeutic radionuclids. These radionuclids produce beta radiation and are concentrated in osteoblastic metastases. Material and Methods: We introduced intravenous administration of Samarium-153EDTMP in 53 patients (29 prostate cancer, 20 breast cancer, 4 kidney carcinoma). Mean applied activity was 40 MBq per kg of patient´s body weight. Results: One month after this administration we observed a significant analgesic effect in 47% of patients, partial analgesic effect in 28% and we noticed no effect in 25% of patients. Three months after the administration we observed a significant analgesic effect in 42% of patients, a partial effect in 36% and no effect in 22% of patients. The withdrawal of bone pain was joined with an improvement of the patients´ mobility and with the decrease of the necessary dose of anodyns and nonsteroid analgesics. 1 and 3 months after Samarium-153-EDTMP administration the following haematologic parameters changes were seen: a) 7% reduction in red cell count in one month after administration, 14% reduction after three months. b) 42% reduction in leukocyte count in one month after administration, 25% reduction after three months. c) 50% reduction in platelet count in one month after administration, 22% reduction after three months. In all three haematological profiles (red cells, leukocytes, platelets) we detected reduction of values after treatment with Samarium-153-EDTMP. This reduction culminates one month after administration and in three months leukocytes and platelets count was getting better. Conclusion: After single administration of Samarium-153-EDTMP we observed analgesic efficacy of various degree in 78% of patients for three months.

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Production and on-line quality control of [15]O2 and C[15]O gases from an RDS111 Cyclotron P.L.B. van Ophemert, G. luurtsema, R. Boellaard, E.J.F. Franssen, A.A. Lammertsma. PET centre, VU University Medical Centre, Amsterdam, The Netherlands. Introduction: Oxygen utilisation and blood volume can be measured in vivo using PET with 15 O2 and C15O, respectively. The purpose of the present study was to develop a gas selection and on-line quality control system for delivery of 15O gases, produced by an RDS 111 cyclotron (CTI, Knoxville, TN), to the PET scanning room. Methods: The standard cyclotron settings for the production of 15O were: 11 MeV protons, 40 µA beam current, 7 minutes irradiation time and a target filling pressure of 250 psi. From 15N2 (95% + 2% O2), 15O2 was produced by the 15N(p,n)15O nuclear reaction. Through the subsidiary nuclear reaction 14N(p,α)11C, production of 11CO2 and trace amounts 11CO was possible. 11 CO2 was trapped on an ascarite column. For production of C15O, 15O2 was converted to C15O using a charcoal column at 900°C. For administration to patients, the following radiopharmaceutical requirements were set: radiochemical purity (RCP) >95%, radionuclide purity (RNP) >95%, half life (T?) for 15O between 115 and 130 seconds, and for CO a maximum of 1 mmol per application. RCP was measured using an online sampling GC (CP9003; Chrompack, Netherlands). The GC-column was a CTR-1, the sample loop 1 ml, and He carrier flow was 20 ml.min–1. For detection a radioactivity (Mini Instrument, type 5-40) and a TCD detector were used. Both detectors signals were registered simultaneously. From these data the radiochemical and chemical purity were calculated. CPM activity graphs were generated, using a VDC-202 dose calibrator (Veenstra, Netherlands). From these curves, T ? and RNP were estimated. Results: Under standard conditions, approximately 3.5 GBq 15O2 was produced (1? minutes EOB). The conversion into C15O was >90%. Approximately 0.2 mmol CO was formed per production. In addition, RCP, RNP and T? values for both 15O2 and C15O routinely met radiopharmaceutical requirements. Conclusion: 15O production and on-line quality control were reliable, reproducible and easy to perform. Only the analysis of “cold” CO was more difficult due to the low sensitivity for CO of the TCD detector. Under the specified conditions, both 15O2 and C15O were suitable for human use.

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Improved diagnostic accuracy of somatostatin receptor scintigraphy (SST-RS) using combined XCT/SPECT in a single device: Vienna experience A. Kurtaran (1), O. Kienast (1), G. Dobrozemsky (1), C. Novotny (1), T. Traub (1), B. Niederle (2), M. Raderer (3), F. Kainberger (4), R. Dudczak (1). (1) Department of Nuclear Medicine of the University of Vienna, Vienna, Austria, (2) Department of Surgery of the University of Vienna, Vienna, Austria, (3) Department of Internal Medicine I of the University of Vienna, Vienna, Austria, (4) Department of Radiology of the University of Vienna, Vienna, Austria. Aim: In this study we assessed the clinical diagnostic value of combined XCT/SPECT in a single device using the novel gamma camera mounted anatomical X-ray tomograph (GMAXT; GE Medical systems, Millennium VG with Hawkeye) in patients undergoing somatostatin receptor scintigraphy (SST-RS). Materials and Methods: In 64 patients with known or suspected tumours expressing SST-R (carcinoid, gastrinoma, glucagonoma, medullary thyroid carcinoma, hepatoma, MALT-lymphoma, melanoma, hypernephroma, thymoma, gall bladder carcinoma) SPECT imaging with 111In-labeled somatostatin analogous and X-ray CT were applied during one single session. The assessment of the results was based on the improvement of the diagnostic accuracy of SST-RS as well as the achieved clinical benefit. For this evaluation SST-RS findings were first interpreted without and then with knowledge of fused scan findings. The fused images were scored according to the following criteria. Group I. Group II. Group III. Group IV.

Improved diagnostic accuracy leading to a change in patient management Improved diagnostic accuracy, but no clinical benefit in the individual patient Better anatomical information but no improved diagnostic accuracy No additional information

Results: The additional information achieved by fused images included better study interpretation, differentiation of physiological from pathological uptake, identification of unexpected/unknown tumour sites. Eighteen out of 64 patients (28 %) were classified to group I, 25 (41 %) to II, 11 (17 %) to III and 10 (16 %) to IV. Conclusion: These data clearly indicate that the combined XCT/SPECT imaging with a single device improves the diagnostic accuracy in patients undergoing SST-RS. Therefore, the use of this technology has a significant clinical impact in patient management.

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Thyroid Cancer I. Zubovic (1,2,3), G. Mikac (1,2,3), M. Biukovic (1,2,3). (1) Clinical Center of Banja Luka, (2) Department of Nuclear Medicine, (3) Faculty of Medicine of Banja Luka, Banja Luka, Republika Srpska, Bosnia and Herzegovina. Thyroid Cancer The aim of the work is evaluation of thyroid cancer among of patients with thyroid disease in the region of Banja Luka in the course of three last decades (1970-2000 year). In the evaluation it was included 13500 patients with thyroid disease in the region of Banja Luka. The diagnosis of thyroid carcinoma is made on anamnesis, physical examinations , laboratory tests, x-rays , ultrasonograms, scintigraphy , fine needle biopsy and histopatological pattern. Among l3.500 patients with thyroid disease in the region of Banja Luka it has been discovered 162 patients with thyroid carcinomas in the course of three last decades, that is 1,2% from total diseases of thyroid gland. The papillary carcinoma accounts 57%, follicular 30%, anaplastic 7% and medullary 6% of all cases with thyroid carcinomas. The thyroid carcinoma occurs more frequentlly in women than in men. The ratio female/male in the papillary carcinoma is 3,4: 1, in the follicular and anaplastic is 3:1 and medullary is 2:1. The peak of incidence of the papillary carcinoma is in the fourth decades of life, the follicular has bimodal frequency, peak occurring in the fourth and sixth, anaplastic in the sixth and seventh and medullary from the fourth to seventh decades of life. Among 1.371 of patients with „cold“ or relatively „cold“ nodules, 148 are malignant, that is 11%. Among 2.125 of patients with functional and hyperfunctional nodules („warm“ or „hot“ nodules), 6 are malignant, that is o,2%. In 141 (87%) patientns with thyroid carcinoma the surgical treatment was performed and patients were treated by the substitution therapy, l-thyroxin, 100-200 µg/day. The radioiodine 131 I , was applied in 48 patients. After the operation 8 (5,7%) patients had damaged n.recurent and hypoparathyroidism in 5 (3,5%) patients. The recurrence of disease is found in 17 patients. In 22 patients who had distant metastases when diagnosis was done the progression of disease was continued.

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Scintigraphic Evaluation Of The Effect Of Repeated Endoscopic Injection Scletherapy On Esophageal Motility A.M. Fawzy (1), G. Ziada (1), SH. Wagih (1), A. Nooh (3), SH. Mahdy (2). (1) Departments of Nuclear Medicine, Faculty of Medicine, Cairo Univerisity, (2) Nasser Institute and, (3) Endoscopy Department, Nasser Institute, Egypt. Bleeding from esophageal varices is a major problem in portal hypertensive cirrhotic patients in Egypt. Endoscopic injection sclerotherapy [EIS] is one of main methods used to control esophageal variceal bleeding. Aim of the study: To assess the effect of EIS on esophageal motility using radionuclide study. Patients and methods: Changes of esophageal motility were studied in 43 cirrhotic patients, who were classified into 3 groups according to the number of EIS: group A: No previous EIS (n=14, m=8), group B: less than 5 EIS (n=15, m=7), group C: more than 5 EIS (n=14, m=8). Imaging was done within one month of last therapy session. Scintigraphic esophageal transit studies were performed in both supine and erect positions. Processing was done by drawing ROI on upper, mid and lower esophageal thirds as well as whole esophagus. Esophageal time activity curves drawn and esophageal transit time (ETT) was calculated for each ROI. Also condensed images were created. Results: ETT in the supine and erect positions respectively were (6.6 ± 1.7 sec) and (5.4 ± 1.3 sec) in group A, (12.6 ± 1.1 sec) and (9.9 ± 1.2 sec) in group B & (17.7 ± 2.2 sec) and (13.6 ± 1.5 sec) in group C, with a statistically significant difference between all groups.

Group A Group B Group C

Upper 1.1 1.3 1.5

Erect Mid 1.9 2.2 2.3

Lower 2.5 6.4 9.6

Upper 1.1 1.3 1.6

Supine Mid 2.1 2.2 2.3

Lower 3.4 9.3 13.6

Conclusion: • EIS affects the esophageal motility significantly with prolongation of esophageal transit time, especially in lower esophageal third. • The affection of esophageal motility after EIS occurs in both erect and supine positions and is more evident in the latter. • The more the number of EIS sessions, the more evident is the effect on esophageal motility.

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WBC-SPECT for mild and medium myocarditis detection and assessment(MRI and biopsy correlations) N.P. Fadeev (1), V.YU. Soukhov (1), S.A. Boytsov (2), M.V. Deryugin (2), I.V. Andoshskaya (3). (1) Nuclear Medicine Dept., Central Research Institute of Roentgenology and Radiology, St-Petersburg, Russia, (2) Military Medical Academy, St-Petersburg, Russia, (3) St.George’s Hospital, St.Petersburg, Russia. The study was performed to assess the clinical value of SPECT with 99mTc-HMPAO labeled autoleucocytes in patients with equivocal signs of myocarditis. Ninety-eight scans in 49 patients (25 females and 24 males) aged 15-47 years with suspected myocarditis were evaluated. Each patient underwent whole-body scanning and SPECT of thorax 99mTc-HMPAO-autoleucocytes and 99mTc-tetrofosmine (for perfusion assessment and better delineating of the heart contours). In 9 patients contrast enhanced MRI (CE MRI) studies and endocardiac biopsy were performed. In 36 patients focal or diffuse increased activity seen in relation to heart walls convincingly demonstrated myocardial inflammation considered as medium myocarditis. Thirteen patients had no distinct tracer uptake (mild myocarditis). In some patients whole body scanning revealed extracardiac infection (frontitis, sphenoiditis, ulcerative colitis, cholecystitis, and adnexitis). CE MRI in 9 out of 36 pts with scintigraphic evidence of myocarditis showed high intesity signal in T1-weighted images from the same regions of the heart. The tissue samples from pointed regions had real inflammatory signs while biopsies of other parts of myocardium were inconclusive The data demonstrated that 99m Tc-leucocytes imaging is effective in ruling out, non-invasively, such inflammatory heart diseases as myocarditis (and simultaneous detection of noncardiac infection) comparably with CE MRI and biopsy.

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O. Blagosklonov (1), E. Itti (2), R. Sabbah (1), P. Guiderdoni (3), M. Meignan (2), J.C. Cardot (1), R. Itti (3). (1) Department of Nuclear Medicine, Jean Minjoz University Hospital, Besançon, France, (2) Departement of Nuclear Medicine, Henri Mondor University Hospital, Créteil, France, (3) Departement of Nuclear Medicine, HCL, Lyon, France.

N.P. Paunkovic, P.A.J. Paunkovic. Medical Centre Zajecar, Yugoslavia.

Imaging CardioWeb Institute: European Network for Cardiac Imaging

Aim: Imaging CardioWeb Institute (ICWI) is an initiative of French medical imaging specialists extended to other European countries. This network provides european cardiologists and medical imaging specialists with high security level communication procedures for transfer and storage of medical imaging data. Material and Methods: High speed access and adequate storage capacities as well as data protection are granted by Cegetel.rss (Reseau sante social network), which holds dedicated intranet infrastructure including physical and software protection tools. The access to the network is secured by a special smart-card delivered by ICWI. This smart-card and the identification protocols are fully compatible with the intranet security systems. The first step of personal identification consists of a comparison of the data from the smart-card with a general database of all card holders, built-up and maintained by RSS; authorized users can be connected to the intranet and have access to common services. After the second step of the identification, which grants access to ICWI intranet site, the members of ICWI can access to specific and personalized ICWI services. Results: ICWI internet site was developed using common standards of web site construction and design. After the connection to ICWI, user’s rights are delimited according to his/her specialty, professional position, experience etc.; information from the smart-card is related to ICWI database – second step of the identification. For example, a cardiologist has access to resulting images of his/her patients (these images are transmitted and interpreted by a medical imaging specialist) and can transfer these images to his/her colleagues but can not modify the comments or send these images to another medical imaging specialist. Only medical imaging specialists have access to raw data and can perform image processing or ask for opinion of other specialists. In addition to transfer and storage services, members of ICWI can use special messaging system and send SMS and/or vocal messages to the cardiologist in case of emergency. The images can be transferred to special patient image databank and the patient can access his/her image(s) using a code protected card. Conclusion: ICWI offers to cardiac imaging specialists from public hospitals or private institutions the secured tools for transfer and storage of resulting images and/or raw data as well as usual web site services (forums, mailing list). This network can be the base for specialized expertise (second opinion) and e-education (“The Unveiled Heart” SW), data mining, multicenter studies and on-line image processing.

Characteristics of two Radio Receptor Assays (TRAK-Assay and DYNOtest TRAK human) for detection of TSH receptor antibodies

Radio receptor assays for detection of TSH receptor antibodies in serum are based on binding competition of TSH-R Abs and 125I “labeled” TSH for membrane preparation of thyrocytes (TBII tests). Until recently, sensitivity of available tests utilizing porcine cell membranes was around 80%. New test (DYNOtest TRAK human, BRAHMS) utilizes human recombinant TSH receptor and human standard material that should improve performance of the test. We have compared results of two assays. Sensitivity of TRAK Assay tested in 356 patients with untreated Graves’ disease was 85% and 96% for DYNOtest TRAK human in 87 newly diagnosed patients. For 53 samples from untreated patients with Graves’ disease group, both tests were performed. TRAK Assay was positive in 42 patients (79.2%) and DYNOtest TRAK human in 51 patient (96.2%). Specificity of the new DYNOtest TRAK human was also improved: in six patients (3 with non immunogenic hyperthyroidism and 3 in stabile remission of Graves’ disease) TRAK Assay was false positive and DYNOtest TRAK human true negative.

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Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition

Histological and arthroscopycal changes after Y-90 isotope treatment in chronic synovitis

RADIONUCLIDE VENTRICULOGRAPHY

M. Szentesi, S. Takács, I. Berkes. Dept.of Rheumatology, Polyclinic of the HospitallerBrothers of St. John of God.Semmelweis Univ., Chair of Rheumatology and Physiotherapy, Budapest, Hungary.

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Background: 1000 patients suffering from chronic synovitis were treated by Yttrium-90 / Y90/ radiosynoviorthesis / RS /. Results were recorded with 70-80% as very good or good. Objectives: our work aimed at examinig arthroscopic and tissue changes as a result of successful radiosynoviorthesis. Methods: 20 patients of them suffering from Rheumatoid Arthritis /RA/ were examined by arthroscop and arthroscopic-biopsy before Y-90 RS, and ?-1 year or two years after the treatment. Results: Before the treatment: The membrane is hyperaemic with grape-like clusters proliferating. The surface was covered with several layers of synoviocyst with a diffuse inflammatory infiltration beneath. After the treatment: Half a year later, no grape-like clusters proliferating, the surface became silk-like. The surface was covered with one layer of synoviocysts, inflammatory infiltration decreased, signs of fibrosis could be seen. The histological picture remained unchanged even 1-2 years later. No damages in cartilage could be seen. Spectral analysis did show no Y in the synovial membrane. Conclusiosns: RS was effective in 70-80% Parallel to the improvement of the clinical pinture the macroscopic and microscopic signs of inflammation were decreasing. membrane or cartilige contained no Y deposits. References: Removed by abstract coordination

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Cardiac dysfunction in HIV patients: studies of left and right ventricular function by isotope cardiography A-M. Lebech (2), B. Hesse (1), J. Gerstoft (2), A. Kjaer (1). (1) Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Copenhagen, Denmark, (2) Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark. Cardiac dysfunction in HIV patients: studies of left and right and left ventricular function by risotope adionuclide cardiography. Lebech A-M, Hesse B, Gerstoft J, Kjaer A. Aim: To study the prevalence of right and left ventricular dysfunctionsided cardiac dysfunction in a Western world modern HIV population from 2001-2.. Materials and Methods: From an outpatient clinic 9Ninety-two 2 consecutive HIV patients without known cardiac or pulmonary sdiseases ymptoms from an outpatient clinic were i studiedncluded. The mean age was 43 years (range 25-63 years), 87% were males. EightynineEighty-two (89 percent%) were NYHA class I and 10 (11%) were NYHA class II. Pulmonary symptoms? . TThe majority of patients (84%) received highly active anti retroviral treatment (HAART). RAll patients had a first-pass radionuclide study performed in order to establish the right ventricular ejection fraction (RVEF) was measured by a first-pass radionuclide study and left ventricular ejection fraction (LVEF) and volumes by a MUGA study with a small field-of-view gamma camera and 99mTc-labelled human serum albumin. RVEF and LVEF were calculated by GE software programmes and volumes determined after attenuation correction (according to an empirically determined factor) and measurement of the depth of the LV centre. In our laboratory 0.50 is the lower normal limit for both RVEF and LVEF. R In addition equilibrium MUGA of the left ventricle was performed in order to establish the left ventricular ejection fraction (LVEF) and the left ventricular volumes. Results: 1Thirteen 3 patients (14%) had an RVEF below 0.50, whereas only 2 (6 of these patients (7%) had a RVEF below 0.45). Two patients (2%) had a LVEF below 0.50. Both patients with reduced LVEF also had also reduced RVEF. The left ventricular end-diastolic volume index (LVEDVI) (LVEDVI) was above the upper normal limit of 80 ml/m2 in 17 patients (18%). There was no overrepresentation of NYHA class II patients in the groups with reduced RVEF (8%) or LVEF (0%). Also the proportion in HAART was similar in patients with and without reduced RVEF or LVEF. There was no connection between increased LVEDVI and decreased RVEF since 15% of patients with decreased RVEF had increased LVEDVI.Var der nogen forskel mellem de 16% af ptt der ikke fik behandlingog de 84 der fik i

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n RADIONUCLIDE VENTRICULOGRAPHY relation til RVEF/LVEF? Var der sammenhæng mellem nedsat RVEF og øget LVEDVI? Conclusions: WIn a HAART eraith the present very active treatment HIV population a certain substantial part of athe HIV poatients pulation have significant, but slight abnormalities of cardiac function with reduced Rreduced function VEF and/or increased left ventricular volume, but of the right side of the heart without cardiac symptoms. . The presence of a possible cardiomyopathy, related to the disease itself or to the present active anti-HIV treatment, may be important to The clinical significance of this as well as the need for monitoring has to be establish with the marked improvement ofin survival of these patientsed.

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Frequency of diastolic dysfunction in the community and in a referral population with and without normal left ventricular ejection fraction. I.P. Clements, D.O. Hodge, C.G. Scott. Mayo Clinic, Rochester, Minnesota, USA. Aim: Although diastolic filling is often abnormal in heart failure with preserved left ventricular (LV) ejection fraction (EF), the frequency of abnormal diastolic filling in other populations is unknown. The aim of this study is to define the frequencies of diastolic dysfunction in three different populations. Materials and Methods: LV peak filling rate (PFR, end-diastolic volumes/sec), time to peak filling rate (TPFR, msec) and first half filling fraction (1/2FF) were measured with radionuclide left ventriculography in 71 subjects (age > 44 years and LVEF > 0.49) selected randomly from Olmsted County, Minnesota (Community) and in second population (Referral) of 921 patients (463 with LVEF > 0.49 and 458 with LVEF < 0.50) of similar age, referred for clinically-indicated assessment of LVEF. Values of PFR, TPFR or 1/2FF <10th or >90th percentile in normals were considered abnormal. Results: PFR, TPFR and 1/2FF were < 10th percentile in 24, 15 and 28 and >90th percentile in 3, 22 and 6 percent respectively in Community; the corresponding frequencies in Referral with LVEF > 0.49 were 46, 14 and 42, and 9, 34 and 5 and the corresponding frequencies in Referral with LVEF < 0.50 were 86, 22 and 61, and 1, 38 and 4. The likelihood of abnormal filling measures differed significantly (p < 0.0001) between the populations. Referral (LVEF < 0.50) compared to Referral (LVEF > 0.49) and Community had more diabetes mellitus (26 vs 16 vs 6 percent, p<0.0001) and myocardial infarction (46 vs 25 vs 4, p <0.0001) and male gender (76 vs 55 vs 52), whereas hypertension, hyperlipidemia and cigarette usage were similar amongst the groups. Conclusions: About a quarter of subjects in the community > 44 years of age with normal LVEF (LVEF > 0.49) have abnormal diastolic filling. In the referral population also > 44 years of age, the incidence of abnormal filling ranges between about 50 percent when the LVEF was > 0.49 to 80 percent when the LVEF was < 0.50. Diabetes mellitus, prior myocardial infarction and male gender were associated with a greater likelihood of diastolic dysfunction.

Mid-term evaluation of left ventricular ejection fraction and telesystolic volume at rest and during effort after biventricular pacing F. Fallani (1), M. Levorato (2), C. Greco (1), A. Moretti (2), S. Fanti (2), R. Franchi (2), M. Biffi (1), A. Branzi (1), N. Monetti (2). (1) Insitute of Cardiovascular Diseases - S.Orsola-Malpighi Hospital, (2) Department of Nuclear Medicine - S.Orsola-Malpighi Hospital, Bologna - Italy. AIM: Biventricular pacing (BVP) has recently been proposed as a therapeutic modality for heart failure (HF) in patients (pts) with dilated cardiomyopathy and left bundle branch block (LBBB). We evaluated the effects of BVP on left ventricular function at rest and during effort at mid-term follow-up by equilibrium radionuclide angiocardiography (ERNA). MATERIAL AND METHODS: 10 pts (mean age 62,4±4,7; M/F=6/4) with severe left ventricular impairment (ejection fraction < 30%), overt HF (NYHA class 3) and without significant mitral regurgitation, underwent ERNA before and after (mean 91±6 days) BVP implantation.. The etiology of dilated cardiomyopathy was ischemic in 4 pts and idiopathic in 6. The scintigraphic images were acquired in the best septal left anterior oblique projection at rest and during mild exercise performed at cycloergometer in semisupine position (fixed workload of 25 Watts). We evaluated left ventricular volumes by the Massardo method and left ventricular ejection fraction (LEF). RESULTS: After BVP implantation we did not observe a significant differences in heart rate (HR) and blood pressure (BP) at rest (HR 82±11 vs 77±14; systolic BP 117±19 vs 114±21) or during mild exercise (HR 113±22 vs 114±18; systolic BP 133±15 vs 127±19). Rest and stress LEF showed a mild improvement trend after BVP (19,2±4,3 vs 23,1±5,9 p 0,054 and 20,4±5,9 vs 23,0±7,2 p 0,23 respectively). Thus we observed a significant reduction of telesystolic volumes both at rest (228,8±48,1 vs 181,8±76,5 ml; p 0,014) either during effort (227,7±74,5 vs 196,6±53,9 p 0,049). CONCLUSIONS: Our data confirm the promising preliminary results of BVP, showing a positive effect on left ventricular remodelling already at a short interval of time since the implantation. We confirmed a reduction of left ventricular volumes also during effort. The improvement of LEF in our pts was not significant as previously observed in others studies, probably due to the different etiology of the underlying disease and to the small sample size.

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Horseshoe vs. Computed Background M. Veljovic (1), V. Bosnjakovic (2), D. Sobic-Saranovic (1), S. Pavlovic (1), N. Kozarevic (1). (1) Institute of Nuclear Medicine, CCS, (2) Center for High Technology, CCS, Belgrade, Yugoslavia. Objectives and Methods. Subtraction of the so called “Horseshoe” background (HB) is a well known approach in planar nuclear cardiology studies. We have previously developed the “Geometric-Count Based” (GCB) method for computing left ventricular volume (LVV) by planar radionuclide ventriculography, the left ventricle (LV) model being based on prolate ellipsoid (with it’s a, b, and c axes, where a = c). The following equation for computing left ventricular end diastolic volume (EDV), that had been described elsewhere (J Nucl Cardiol, 2, 2, S 101, 1995), was developed: EDV(cm3) = 2 c * M2 * Ctot / Cmax ; where: c - manually drawn short axis (one pixel-row ROI) of prolate ellipsoid in LAO 45 (cm); M - calibrated pixel size (cm2); Ctot - total counts in LV ROI (cts); Cmax - maximum pixel (voxel) counts in LV ROI (cts). However, subtraction of the conventional HB from LV ROI underestimated LVV computed by GCB method in clinical studies compared to the contrast ventriculography data. Therefore, we developed the “Computed” background (CB) approach. First, the approach assumes definition of coordinates of four specific points along the edge of a quarter of the central (maximal) ellipse (i.e. ellipse of central longitudinal cross section of ellipsoid) in order to find the average coordinate value for central ellipse edge, thus providing for the relative average depth of ellipsoid from its edge (“factor edge” – Fedge) by adequate interpretation of ellipsoid equation. Maximum ellipsoid depth from its edge is given by its c (=a) axis taken to be proportional to a voxel with maximum counts - Cmax (cts). One should draw the ED ROI (cts) (assumption: central elliptic cross section of the LV ellipsoid), transversal one-pixel row line (cts) across LV ROI (assumption: maximum c/2 axis, i.e. maximum depth of LV from its edge) and derive the average No of counts – Cmean (cts) along the ellipsoid – ED ROI edge. Then, after the above ROIs had been drawn, the following equation for computing CB (cts) to be automatically subtracted from ED ROI (cts) was developed: CB = [Cmean – (Cmax * Fedge)] / (1 - Fedge). Results of physical experiments (checking known volumes of the vessels having elliptic and rectangular shapes) have shown that the GCB method with CB subtraction correctly measures volumes of any vessel shapes (error: ± 2.0 – 3.0 %), while in clinical evaluation correlated well with contrast ventriculography data (r = 0.94; p< 0.01). In conclusion, CB has a definite advantage over HB when computing EDV by our GCB method. O

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E. Entok (1), Y. Cavusoglu (2), E. Kaya (1), A. Birdane (2), A. Unalir (2), E. Vardareli (1). (1) Department of Nuclear Medicine,Osmangazi University Medical Faculty, Eskisehir, Turkey, (2) Department of Cardiology,Osmangazi University Medical Faculty, Eskisehir, Turkey.

D. Sobic-Saranovic (1), S. Pavlovic (1), N. Kozarevic (1), T. KuljicStojanovic (1), M. Lekic (1), O. Vucinic (2), N. Vasic (2), V. Bosnjakovic (1). (1) Institute of Nuclear Medicine, CCS, Belgrade, Yugoslavia, (2) Institute for Lung Diseases and TB, CCS, Belgrade, Yugoslavia.

In recent years a great interest has increased in dyslipidemia. Dyslipidemia has been reported to impair left ventricular systolic (LVs) and diastolic (LVd) functions irrespectively of atherogenic effects in the setting of Coronary Artery Disease (CAD). The aim of the present study was evaluate of the effects of dyslipidemia on LVs and LVd functions by means of radionuclide Ventriculography (RNV)) in subjects with signs of dyslipidemia and with preserved LV function. Methods: Twenty-eight patients with dyslipidemia and normal LV function, valideted by clinical and echocardiographic examinations, negative exercise stress test with (groupI, n=19, mean age 50±10y, 10 women, 9 men) and without dyslipidemia (group II, n=9, mean age 47±11 years, 6 women,3 men) were included into the study. Dyslipidemia was defined as lowdensity lipoprtoein level exceeding into the study. Dyslipidemia was defined as low-density lipoprotein level exceeding 160 mg/dl. The exlusion criteria were any disease that could influence LV function such as CAD, hypertension, diabetes, cardiomyopathy and valvular heart disease Radionuclide Ventriculography (RNV) was performed in all subjects using the best septal position, which differentiates LV and right ventricle. The following parameters were calculated: Ejection fraction (EF), Peak Ejection Rate (PER), Time to Peak Ejection (TPER), 1/3Ejection Rate (1/3 ER), 1/3Ejection Fraction (1/3 EF), Peak Filling Rate (PFR), Time to Peak Filling Rate (TPFR), 1/3Filling Rate (1/3FR), 1/3 Filling Fraction(1/3FF). Results: PER, 1/3ER, PFR and 1/3 FR were found to be significantly lower in subjects with dyslipidemia compared to those without dyslipidemia. Conclusion: Though clinically and echocardiographically global LV function was normal in sujects with dyslipidemia, RNV demonstrated dyslipidemia partly impair LVs and LVd hemodynamic parameters.

The aim of this study was to evaluate left ventricular function in patients with pulmonary sarcoidosis (PS) grades I and II by radionuclide ventriculography. The study included 50 subjects, 40 patients mean age 40 ± 12 years, 12 males and 28 females, and 10 subjects without previous lung or heart diseases (control group-CG). Pulmonary sarcoidosis was diagnosed in all patients based on their clinical and radiological findings. Radionuclide ventriculography was performed in a standard way after in vivo labeling of red blood cells with 740 MBq of 99mTc-pertechnetate in left anterior oblique projection. Ejection fraction (EF) and first third EF (1/3 EF) as systolic left ventricular parameters and peak filling rate (PFR) and time to peak filling rate as diastolic parameters were assessed in all subjects in the study. Phase and amplitude images as regional left ventricular parameters were also evaluated. Results: There was no statistical difference found inn EF between patients with PS and CG (62.2 ± 4.9 % vs. 64.7 ± 2.8 %, p>0.05, respectively) as well as in 1/3EF ( 22.4 ± 4.6 % vs. 26.7 ± 1.5 %, p> 0.05, respectively) and in TPFR : 175.3 ± 22.6 ms vs. 143.2 ± 7.8 ms, p>0.05, respectively). There was difference found between groups in PFR as diastolic parameter of left ventricular function ( PFR: 2.15 ± 0.40 EDV/s vs. 2.84 ± 0.25 EDV/s, p<0.05, respectively). In 22/40 ( 55%) of patients with PS amplitude analysis revealed mild reduction of anteroseptal heart contraction, while phase image was normal in all subjects. Conclusion: Our results suggested that in initial stages of PS ( grades I and II) mild left ventricular diastolic dysfunction with decreased value of PFR may be present, as well as in some patients reduction of heart contraction in anteroseptal region.

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Effects of Dyslipidemia on Left Ventricular Systolic and Diastolic Functions in Healthy subjects: Preliminary study

Radionuclide ventriculography in noninvasive assessment of left ventricular function in patients with lung and heart sarcoidosis

Gated blood pool SPET and geometric count based method in noninvasive assessment of left ventricular volumes in comparison with contrast ventriculography and echocardiography

Right RV) and left ventricular LV) ejection fraction (EF) evaluation in patients with chronic pulmonary diseases CPD) Comparison of methods.

D. Sobic-Saranovic (1), M. Veljovic (1), S. Pavlovic (1), N. Kozarevic (1), B. Vujisic (2), J. Saponjski (2), M. Ostojic (2), V. Bosnjakovic (1). (1) Institute of Nuclear Medicine, CCS, Belgrade Yugoslavia, (2) Institute for Cardiovascular Diseases, CCS, Belgrade, Yugoslavia.

I. Iakovou (1), N. Karatzas (1), A. Psarakou (2), D. Oikonimidis (3). (1) Nuclear Medicine dpt of Aristotle University of Thessaloniki Greece, (2) Medical Physics dpt of Aristotle University of Thessaloniki Greece, (3) Pulmonary lab. of Aristotle University of Thessaloniki Ippokratio hsp. Greece.

Accurate measurements of left ventricular volumes (LVV) is clinically important for the evaluation of cardiac function, especially as a prognostic value in patients with myocardial infarction, dilative cardiomyopathy and in follow-up of remodeling processes of left ventricle (LV). The aim of this study was to evaluate LV end-diastolic (EDV) and end-systolic (ESV) volumes by gated blood pool SPET GASPET), geometric-count based (GCB) radionuclide method and 2d-echo technique in comparison with contrast ventriculography (CV) as a gold standard. Patients and method: We studied 48 subjects, 38 patients with coronary disease and 10 healthy volunteers without previous cardiac diseases. GASPET studies (commercial program) were performed in all subjects in 32 projections over 180 degrees, gated for 16 frames/cycle. Planar radionuclide studies used our own GCB method, while volumes assessed by 2D-Echo technique used Teicholtz formula. Results: Correlation between GASPET and CV were for EDV: r = 0,90, for ESV = 0.89, respectively, and between GASPET and 2D-Echo for EDV: r = 0.92, and ESV: r = 0.93, respectively. Correlation between GCB and CV were better for EDV: r = 0.93 and for ESV: r = 0.92, then between GCB and 2D-Echo ( EDV: r = 0.88, ESV: r =0.89), respectively. Volumes measured by GASPET and GCB methods showed mutual correlation for EDV: r = 0.90, and ESV: r = 0.88, respectively. Correlation between 2d-Echo and CV were for EDV: r = 0.87 and for ESV: r = 0.86, p<0.05, respectively. Conclusion: Our results suggested that radionuclide methods, especially GCB method, are accurate non-invasive methods for left ventricular volume measurements.

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Aim: Evaluate RVEF and LVEF in patients with chronic pulmonary disease (CPD) during a standard isonitrilium myocardial perfusion study. Materials and methods: Forty patients, (14 women), 67.7 ± 7 years old suffering from CPD enrolled in this study. Patients were consecutively submitted to: 1) first pass (FP) angiocardiography with Tc99m (?c-FP). 2) Multigated angiocardiography (MUGA) 3) FP with 99mTcsestamibi (MIBI-FP) 4) gated FP (MIBI-gFP) and GatedSPECT was performed in 23 patients. A simple SPECT study was performed to the rest of them. Results: Right ventricle: RVEF was measured by each method: ?c-FP =49.09±8.4%, MUGA =48.51±10.6%, MIBI-FP =49.45±7.8 % and MIBI-gFP =52.49±6.05%. No difference among them was noted (p=0.674). MIBI-FP ejection fraction range was wider than MIBI-gFP and narrower than MUGA. A strong correlation (r=0.88 p<0.01) and good agreement was found between MIBI-gFP and MIBI-FP . Less strong correlation was estimated between not only TcFP and MUGA (r=0.76 p<0.01) but MIBI-FP and MUGA (r=0.68 p<0.01) as well with no sufficient agreement. Left ventricle: LVEF was also measured by each method: ?c-FP=61,1±8,5%, MUGA=61,2±10%, MIBI-FP=61,8±6%,EF GSPECT=60,2±7%. There was a strong correlation (r=0,87 p<0,01) with good agreement between ?c-FP and MUGA. For all patients, correlation between MIBI-FP and GSPECT was weak (r=0,62 p<0,01) but ameliorated by the exclusion of 4 patients with small end diastolic volumes (EDV) (r=0,82 p<0,01).The correlation between MUGA and GSPECT got stronger (r=0,85 p<0,01) by the same exclusion. Finally a strong correlation (r=0,81 p<0,01) with sufficient agreement was noted between MIBI-FP and MUGA. Conclusion: Right ventricle: simple or gated FP are reliable with good agreement methods of RVEF evaluation in patients with CPD that can easily be performed during every isonitrilium myocardial perfusion study. MUGA is proved to be comparative to the first pass estimation of right ventricular EF .The gFP affords the narrowest range of RVEF calculated, allowing the more accurate functional identification of right ventricular borders. Left ventricle: FP (with Tc or with Sestamibi-Tc) is a reliable method of LVEF measurement in patients with CPD comparing it with MUGA. ????-FP can evaluate LVEF during a standard myocardial perfusion study with isonitrilium GSPECT-EF correlation with EF measured by MUGA or FP is strongly affected by EDV

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Left ventricular function at rest and exercise in never-treated hypertensive female assessed by radionuclide ventriculography: Comparison with normal volunteers N. Topuzovic, I. Karner, A. Rusic, B. Krstonosic. Department of Nuclear Medicine, Osijek University Hospital, Osijek, Croatia. Aim: The aim of this study was to investigate left ventricular systolic and diastolic function at rest and during exercise in never-treated female hypertensive patients. Materials and Methods: Seventeen female patients with newly established, uncomplicated essential hypertension (aged 30 to 47 years) were examined by means of maximum physical exercise testing and radionuclide equilibrium ventriculography. Obtained parameters were compared to 23 female normotensive volunteers of comparable age. Results: Mean blood pressure were significantly higher in patients at rest and during exercise than in controls (121±13 vs. 89±7 mm Hg, and 143±11 vs. 122±9 mm Hg, respectively, p<0.001). At peak exercise patients achieved a similar workload and exercise duration. Increase in heart rate during exercise was similar in patients and controls (from 75 ± 10 to 139 ± 14 vs. 72 ± 8 to 142 ± 16 beats/min, respectively). Ejection fraction (EF) at rest and stress did not differ significantly between patients and controls (54 ± 10 vs. 55 ± 8%, and 70 ± 10 vs. 66 ± 8%, respectively), but % rise in EF during exercise was significantly higher in patients. At rest and during exercise, there were no significant difference in peak ejection rate (PER) and time to PER (TPER) between patients and controls. Patients had similar peak filling rate (PFR) at rest (2.88 ± 0.79 vs. 2.76 ± 0.76 EDV/s) and during exercise (5.85 ± 1.86 vs. 6.21 ± 1.97 EDV/s), in addition to nonsignificant difference in time to PFR (at rest 143 ± 62 vs. 146 ± 42 ms at rest, and 97 ± 20 vs. 91 ± 19 ms during exercise). Conclusion: Female patients with newly diagnosed, never-treated hypertension have preserved systolic and diastolic function, and maximal exercise performance.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition GATED PERFUSION SPECT - METHODOLOGY

P_64

Normal parameters of left ventricular volume and ejection fraction measured by gated myocardial perfusion SPECT: Comparison of Tc99m MIBI and Tl-201 IY. Hyun. Hyun (1), DH. Kim (2), JK. Seo (2), J. Kwan (2), KS. Park (2), WS. Choe (1), WH. Lee (2). (1) Nuclear Medicine, Inha University College of Medicine, (2) Internal Medicine, Inha University College of Medicine, Inchon, Korea. Aim: We examined radioisotope-specific differences of normal limits for left ventricle (LV) volume and ejection fraction (EF) between Tc-99m MIBI and Tl-201 myocardial perfusion gated SPECT (g-SPECT). Material and Methods: Rest Tl-201/post-stress Tc-99m MIBI g-SPECT measurements with acquisitions of 8-frame were evaluated for 73 patients (mean age 56 ± 14, 66% female) who either had < 5% pretest likelihood of CAD (n = 11) or had normal coronary angiography and echocardiography (EF > 50%) (n = 62). LVEF, LV end-diastolic volume (EDV), end-systolic volumes (ESV) were automatically determined by quantitative gated SPECT (QGS). Results: Similar results were obtained for mean LVEF between Tc-99m MIBI and Tl-201 gSPECT measurements. By Contrast, Tl-201 g-SPECT had significantly lower LV EDV and ESV values than Tc-99m MIBI g-SPECT (p<0.001). On Tc-99m MIBI g-SPECT, women (EDV; 71.0 ± 17.2 ml, ESV; 27.0 ± 9.7ml, EF; 62.7 ± 6.1%) had significantly lower LV volumes (p<0.01) and similar LVEF compared with men (EDV; 91.1 ± 24.4 ml, ESV; 35.3 ± 13.6ml, EF; 61.9 ± 5.8%). On Tl-201 g-SPECT, women (EDV; 64.8 ± 16.4 ml, ESV; 22.9 ± 8.3ml, EF; 64.9 ± 7.0%) had significantly lower LV volumes (p<0.001) and higher LVEF (p<0.05) compared with men (EDV; 80.3 ± 20.4 ml, ESV; 31.8 ± 11.2ml, EF; 61.5 ± 6.8%). EDV ESV EF

Tc-99m MIBI 79.0 ± 22.3 30.3 ± 12.0 62.3 ± 6.0

Tl-201 71.0 ± 19.5 26.5 ± 10.4 63.5 ± 7.1

P value < 0.001 < 0.001 ns

Conclusion: These data provided radioisotope-specific differences of normal limits for LV volume and EF measurements between Tc-99m MIBI and Tl-201 g-SPECT. Therefore, the evaluation of cardiac function in patients should consider radioisotope-matched normal values.

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D. Daou (1), M. Haidar (2), T. Fourme (3), P. Colin (3), R. Lebtahi (2), C. Vanhove (4), P.R. Franken (4), M. Slama (3), D. Le Guludec (2). (1) Dept of Nuclear Medicine, Lariboisière hospital, AP-HP, Paris, France, (2) Dept of Nuclear Medicine, Bichat hospital, AP-HP, Paris, France, (3) Dept of Cardiology, Antoine Béclère hospital, AP-HP, Clamart, France, (4) Dept of Nuclear Medicine, Free University hospital,Brussels, Belgium.

H.P. Pena (1,2), G.C. Cantinho (1,2), A.V. Veiga (1), D.M. Marona (1), P.G. Gomes (1), F.G. Godinho (1,2). (1) Atomedical, Lab. Medicina Nuclear, Lisboa, Portugal, (2) Instituto de medicina Nuclear - Faculdade de medicina de Lisboa, Lisboa, Portugal.

Aim: Electrocardiographically (ECG) gated blood-pool SPECT (GBPS) is a simple, highly reproducible, and accurate technique for left ventricular (LV) ejection fraction (LVEF) and volume measurement. Recently, an interesting completely automatic GBPS processing software has been reported by Vanhove C et al (GBPSV). Its LVEF has been validated versus planar radionuclide angiography (RNA) but no validation concerning LV volume against a gold standard method has been reported. Materials and Methods: We studied the performances of GBPSV for the evaluation of LVEF (n=29) and volumes (n=58) in 29 patients with CAD. The LVEF provided by the planar equilibrium RNA left anterior oblique view (planarLAO) and LV volumes provided by LV contrast angiography (Rx) were used as gold standards. Results: In 1 patient, the GBPSV automatic segmentation of LV cavity failed because it included simultaneously both the LV and right ventricle. GBPSV presents good reproducibility with an intraobserver and interobserver paired absolute difference of 0±3% and -2±5% for LVEF and intraobserver and interobserver variability of 3±8% and 1±15% for LV volume respectively. LVEF provided by GBPSV is highly correlated to planarLAO (r>0.96; P <0.001) but is significantly higher (P <0.05). There is no correlation between the average and paired absolute difference of GBPSV LVEF and planarLAO. The corresponding limits of agreement are relatively large [-33%;+20%]. LV volumes provided by GBPSV are highly correlated to Rx (r>0.7; P <0.001) but are significantly lower (P <0.0001). There is a linear correlation between the average and the paired absolute difference of volumes calculated with GBPSV method against Rx LV volumes (r=0.52; P=0.0001). The corresponding 95% limits of agreement are relatively large [-71%;+26%]. Conclusion: GBPSV is an interesting completely automatic software with high success rate. It is a reproducible and accurate technique for LVEF and volume measurement.

Perfusion Gated SPECT - Ejection Fraction Variability, as a Function of the Software

The rapid evolution of technology obligates us, to usufruct of the most modern advances, to acquire new equipments from different manufacturers. This is a problem because results have a diagnostic and prognostic value and that a follow-up is needed for almost all patients, mostly when there are quantitative manipulations of the images which implicates their reproductibility. Aim: Our purpose was to evaluate the degree of reproducibility of quantitative values of cardiac function, depending on two different softwares. Materials and Methods: We studied 118 patients (pts), 49 females and 69 males. 95 of them had no acute myocardial infarction (AMI) in the past, 17 had had AMI and 16 were diagnosed with dilated cardiomyopathy (DCM). Each study was acquired on an ADAC Vertex gamacamera in a total of 64 views, 64×64 matrix, 30 s/view at rest and 40 s/view at stress, with gated acquisition. Afterwards, the images were transferred to the GE Millennium. The software used in the ADAC Vertex gama-camera was based on the Germano’s algorithm (Gsw) (Autoquant with QGS and QPS calculations). In the GE Millennium gama-camera, we used the ECToolbox (Cequal quantification) software (Tsw). For all the pts, the comparison was made based on the ejection fraction (EF), the end diastolic volume (EDV) and the end systolic volume (ESV). We used paired Student T test for statistical analysis. Results: In all the analyzed groups (normal, ischaemia, AMI), we always found higher values of EF and smaller ESV in Tsw, with statistically significant differences (p< 0.05). The differences in EDV calculations are not statistically significant (p>0.05). In the 16 pts with DCM, the results are not statistically different: GswEF = 29.2±6%, GswEDV = 214±47ml, GswESV = 149.6±41.6ml. TswEF = 33.7±9.6%, TswEDV = 192.7±43.4ml, TswESV = 127.9±39.4ml. Conclusions: 1. There are statistical differences in the parameters of LV function, depending on the software, except for EDV. It seems that little volumes, as ESV, overlap the results. 2. Only in dilated cardiomyopathy, the results are similar, perhaps, because of LV’s greater dimensions. 3. These values have diagnostic and prognostic importance. 4. Be careful when using automatic unknown softwares.

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Poster Presentation

Measurement of left ventricular function with ECG-gated blood pool SPECT: value of a an automatic processing method

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A prospective study to evaluate Tc-99m Tetrofosmin LVEF obtained at rest and stress compared to Tc-99m Ultratag MUGA LVEF. A report of 50 patients. F.L. Weiland (1), P.R. Vande Streek (1), S.R. Peters (2), G. Obranovich (1), C. Parice (3). (1) Sutter Roseville Medical Center Nuclear Medicine Department, (2) Sutter Roseville Medical Center Cardiology Department, (3) Sutter Institute For Medical Research, California, USA. Aim: To determine the accuracy of left ventricular ejection fraction calculated from Tc-99m Tetrofosmin rest/stress gated myocardial perfusion images using Cedars and Emory Toolbox algorithms to LVEF from Tc-99m Ultratag as the comparator. Materials and Methods: Twenty-two females and 28 males over 18 years of age underwent a rest and stress gated SPECT wall motion and ejection fraction and a Tc-99m Ultratag MUGA within 5 days of the stress/rest imaging. Left ventricular ejection fraction was calculated using both Cedars Sinai QGS and Emory ECT Tool box R, R1, R2. Nine LVEF measurements per patient were recorded (QGS, R, R1, R2 at rest, stress, and MUGA). Pearson correlations, scatter plots, and paired t-tests of the absolute difference were used to analyze the association between LVEF obtained under rest and stress conditions using MUGA as the standard of truth. In addition, the differences between the GSPECT data and MUGA were plotted against the MUGA determined LVEFs. Results: As expected, all LVEF at rest and stress were positively correlated with MUGA LVEF. Paired t-tests showed the absolute differences between each condition and MUGA were statistically significantly different from 0 (p<.01) (Table 1). The differences were not clinically meaningful. The plots suggested that both QGS rest and stress underestimates MUGA with less variability seen in the stress condition. There was very little difference in the bias between the stress and rest R conditions but both appear to overestimate MUGA. The R1 stress and rest conditions have a similar dispersion pattern to those in the R condition but both of these conditions tend to underestimate MUGA. There were very few patients with LVEFs of less than 50% making it difficult to determine the performance of the various SPECT-determined LVEFs in patients with severe LV dysfunction. Conclusion: This study demonstrates that Tc-99m Tetrofosmin rest or stress gated images may be used to predict left ventricular ejection fraction. All measures may over or underestimate LVEF when using Tc-99m Ultratag MUGA as a comparator. (n=50)

Mean (SD)

MUGA REST QGS STRESS QGS REST R STRESS R REST R1 STRESS R1 REST R2 STRESS R2

57 (12) 51 (12) 54 (13) 59 (14) 61 (14) 52 (13) 53 (13) 65 (17) 68 (17)

Absolute Difference between MUGA (SD)

Correlation with MUGA

8.22 (6.75) 6.62 (5.20) 6.12 (5.60) 7.44 (5.38) 7.50 (5.68) 6.86 (5.65) 10.18 (7.76) 11.72 (8.77)

.745 .802 .810 .808 .811 .801 .811 .817

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Is 16-Frame Gated Tc-99m Sestamibi SPECT different from 8-Frame Gated SPECT in Evaluation of Myocardial Perfusion and LVEF? T. Wen, C.Y. Wen. Department of Nuclear Medicine of the Tzu-Chi University and Hospital, Hualien, Taiwan. The study is to determine whether evaluation of myocardial perfusion and LVEF by gated Tc99m Sestamibi myocardial SPECT acquired in 16 frames per RR interval is different from that by 8-frame gated SPECT. Materials and Methods: Eighteen consecutive patients (Mean age 54±3, 7 males) referred to our nuclear cardiology laboratory underwent exercise stress/rest Tc-99m Sestamibi gated SPECT. One-day stress/rest protocol was performed with 370 and 740 MBq Tc-99m Sestamibi injected at peak exercise and 3hr later at rest. Stress and rest imagings were acquired 30 and 60 minutes post injection respectively. 8-frames per interval was acquired first, followed immediately by 16-frame acquisition without moving the patient. Gated SPECT data was processed by Xpert software (GEMED, Ltd) for three-dimensional myocardial perfusion display as well as semiautomatic quantitation of LVEF’s. Results: 16-frame acquisitions produce visually enhanced perfusion in 33% of patients undergoing treadmill exercise and 11% at rest. Semiautomatic quantitations of LVEF’s are, however, not significantly different by16-frame as compared to 8-frame acquisitions. 16-frame over 8-frame Exercise TC Perfusion No change 11/18(61%) Improved 6/18(33%) Worse 1/18(6%) ?LVEF -0.5±1.2* * LVEF change is not significant at P<0.05

Rest 16/18(89%) 2/18(11%) 0/18(0%) 0.7±0.7*

Conclusion: 16-frame gated Tc-99m Sestamibi SPECT enhances myocardial perfusion during exercise when compared to 8-frame gated SPECT. LVEF quantitation is, however, not significantly affected by either mode of acquisitions.

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Normal Functional Parameters Of Left Ventricle In Perfusion Gated SPECT G.C. Cantinho (1,2), H.P. Pena (1,2), J.M. Monteiro (1), A.D. Daniel (1), H.C. Chester (1,2), F.G. Godinho (1,2). (1) Atomedical, Lab. Medicina Nuclear, Lisboa, Portugal, (2) Instituto de Medicina Nuclear - Faculdade de Medicina de Lisboa, Lisboa, Portugal. Perfusion gated SPECT is widely used for the evaluation of patients with the suspicion or diagnosis of CAD. The simultaneously functional information obtained is of very important clinical value, however, it’s necessary to establish normal range values. Aim: Our goal was to define, in a normal population, the values of cardiac function at rest and stress, based on the perfusion gated SPECT. Materials and Methods: 50 patients with low probability for CAD were studied. 29 females, with an average age of 63±11y and 21 males of 62±12 y, all with normal myocardial perfusion test. All the patients underwent a Gated SPECT with a total activity of 40 mCi of 99mTcTetrofosmin: first the rest scan and afterwards, the gated SPECT scan, never more than one hour after dipyridamole stress test. The studies were acquired in a gama-camera Adac Vertex and then analyzed qualitatively and quantitatively through the Germano’s algorithm. Maps of perfusion (QPS) and function (QGS) quantifications were obtained. Results: The global results for chamber’s volumes at stress are 52.2±18.8 ml and at rest 52.7±19.9ml, higher for men and lower for women, statistically different (p<0.05). The same is for wall mass: stress=117.9±25.9ml and rest=116.8±20.6ml. The same differences are found between males and females. Statistical differences are found if we compare global end diastolic volume with the LV volume at stress (no gated SPECT): 77±23.8 ml and 55±18 ml (p<0.05). The same differences were obtained for males and females. Global ejection fraction=66.4±7.3% with no significant differences between sexes (females: 69±4.8% and males: 62±6.5%). Conclusions: We haven’t found any statistically significant difference in the value of the volumes at stress and rest, when obtained in a non-gated study. The absence of cardiac chamber dilation at stress is an additional important clinical sign. When the cardiac chamber’s volumes are obtained in a gated study, they are significantly higher than those obtained in a non-gated study, as expected. There is a significant difference in the volumes of the cardiac chamber and the ventricle mass between sexes. The higher value of the ejection fraction for the females is a probable consequence of the lesser dimensions of the cardiac chamber and its overvaluation. The homogeneity of this population and of the obtained results improves our safety in valuing these results in our department’s routine.

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J.L. Lear, J.P. Pratt. University of Colorado Health Sciences Center, Denver, Colorado, USA.

H. Rajabi (1), A.R. Bitarafun (1), N. Yaghoobi (2), H. Firouzabady (2), F. Rustgou (2). (1) Dept. of Medical Physics, Tarbiat Modarres University, Tehran,Iran, (2) Dept. of Nuclear Medicine, Shahid Rajaie Heart Hospital, Tehran, Iran.

Filter selection for Tc99m-sestamibi myocardial perfusion SPECT imaging

Aim: Recent reports evaluating automatic left ventricular ejection fraction (LVEF) determination from gated perfusion SPECT (GSP) data indicate that many commercially available programs significantly overestimate LVEF values, particularly in women and in patients with lower than average end-diastolic volumes. We evaluated the causes of these inaccuracies and developed a program to more accurately compute LVEF values automatically. Materials & Methods: Our method differs from other automated methods. First, the GSP data is reconstructed using a specifically-created resolution enhancement filter as opposed to the commonly used Butterworth filter. Next we compute the center of mass of the left ventricle (with user defined outer border) of summed GSP data. Finally, myocardial wall maximum activity locations are determined using a resolution-dependent search method. Gated perfusion (Tc99m-sestamibi) SPECT data from 20 male and 20 female patients with normal perfusion scans were analyzed. The scans were acquired over 180 degrees (30 degree right anterior oblique to left posterior oblique, every 3 degrees, with acquisition time of 60 seconds per stop) using a triple headed gamma camera. The data were processed using a clinically validated manual region of interest end-diastolic and end-systolic determination, our method, and a standard commercially available automated method. Results: The mean LVEF computed using our automatic program was 58%. This value compares to the manually computed value of 57% and to a value of 69% using other commercially available software. The standard deviation between LVEF values from our method and the reference manual method was 4%. Conclusions: The manual computation of gated SPECT LVEF has previously been shown to be accurate and our mean, automatically-computed, value of 58% is nearly identical to the manually computed value of 57% in normal patients. Our method is significantly, p<.001, more accurate than other automatic methods. Reasons for the better accuracy include the use of a non-blurring prefilter in the SPECT reconstruction, user-excluded background noise elimination, and a resolution-dependent search for the location of maximum myocardial wall activities.

Myocardial perfusion SPECT imaging with Tc99m-sestamibi is the most accurate noninvasive means of detecting coronary artery disease and assessing the severity of perfusion abnormalities in the patients with coronary stenosis. Though simple and straight forward the results produced by the technique is very much affected by the details being used. One of the main problems with the test, which has created a lot of discrepancies, is the selection of proper filter and adjustment of the filter parameters to individual cases. In this study we have analyzed and compared four widely used filters for myocardial Tc-99m sestamibi SPECT study i.e. Hanning, Butterworth, Metz and Wiener. The aim of the study was to find the most suitable filter for this type of study and to verify the theoretical peculiarity of the filters in practice. Materials and methods: Patients with proven coronary artery abnormality were selected. Images were reconstructed using 120 filtering conditions. The contrast produced by each filter was calculated. Based on contrast calculated at defected area and visual inspection of five nuclear medicine experts filters were classified. Results: For each filter the range of parameters that produced the maximum contrast with respect to the angiography was determined. Some similarity was found between Metz and Wiener in one side and Butterworth and Hanning on other side. On the average it was found that Metz with the FWHM of 4mm and order of 9.5 to have the maximum rank in all group. Conclusion: Filter selection is an important part of data processing in SPECT imaging. The extent and distribution of noise in tomographic images are very much depended upon the method of reconstruction being used. Among different filter used in routine practice of nuclear medicine, Metz filter found to be the most suitable which produced the more stable and better matched the results of angiography.

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Validation of left ventricular ejection fraction (LVEF) by gated99mTc-Tetrofosmin-SPECT (g-SPECT) in routine clinical practice W.M. Schaefer (1), T. Namdar (1), K.-C. Koch (2), S. Block (1), B. Nowak (1), U. Buell (1). (1) Department of Nuclear Medicine, University Hospital, UK Aachen, (2) Department of Internal Medicine I., University Hospital, UK Aachen, Germany. Aim: Aim of the study was to validate estimated LVEF by g-SPECT in direct comparison to the contrast-left-ventriculography (CV). In addition we evaluated the effect of perfusion defects on the accuracy of g-SPECT LVEF. Materials and Methods: 57 patients (46 m, 11 w; 66±10 a) referred for myocardial perfusion imaging underwent routinely g-SPECT and CV and were included retrospectively into the study. The g-SPECT-acquisitions were done 60-120 min p.i. (under resting conditions) of 800 MBq 99mTc-Tetrofosmin. A triple-head-camera (MS3, Siemens) was used for acquisition. Parameters: 8 gates/RR interval, 20 views, 30 s/view, matrix 64x64. LVEF calculation of the g-SPECT data by QGS, of the CV (30-50/s) by using the Sandler-Dodge approach. Results of both methods were tested with the student t-test for paired samples. In order to quantify the influence of perfusion deficits in the g-SPECT data on the comparison, two sub-groups were analysed: unimpaired perfusion (A, n=26), and perfusion reduced at rest compared to our normal database (B, n=31). Relative LVEF differences ((LVEF(CV)-LVEF(gSPECT))/mean LVEF) were tested for variability between group A and B using the student t-test for unpaired samples. Results: Mean LVEF (n=57) determined by g-SPECT was 52.5±11.2%, or 65.4±13.9% by CV resp., revealing a significant difference (p<0.0001). However, the LVEF values from gSPECT and CV correlated well and significantly (R=0.73; p<0.0001), showing a slope of 0.9 varying only few from the ideal value 1.0. The student t-test for unpaired samples showed no significant difference (p=0.26) between relative LVEF differences of group A (LVEF: gSPECT 57±9%, CV 72±8%) and group B (LVEF: g-SPECT 49±12%, CV 59±15%). Conclusion: The correlation of the LVEF-values (g-SPECT vs. CV) is good in routine clinical practice, even if SPECT data show a perfusion deficit. However, a systematic underestimation of LVEF with g-SPECT in comparison to CV occurred. This underestimation may be explained partly by the smaller temporal resolution of the g-SPECT acquisition. Therefore, defining a threshold to separate pathological from normal g-SPECT LVEF-values should be done by g-SPECT reference–values and not by the established values of the CV.

Coregistered Vectorcardiography and Tc-99m Tetrofosmin Myocardial SPECT. A Novel Computer Approach for Biomedical Data Analysis H.F. Fielding (1), I. Loutfi (1), M.K. Nair (1), M. Zubaid (2). (1) Nuclear Medicine Dept, Faculty of Medicine, Kuwait University, (2) Dept of Medicine, Faculty of Medicine, Kuwait University. Objective: Fusion of electrophysiologic data from the vectorcardiogram (VCG) with SPECT images of myocardial perfusion was achieved to provide a three dimensional mapping of electrical activity onto the myocardium. Materials, Methods and Results: The VCG and SPECT data were obtained from patients referred for stress-rest myocardial perfusion studies. The VCG was recorded according to the Frank orthogonal lead system using a Case 16 ECG treadmill machine (Marquette). Digital data on the VCG was saved from each patient for further analysis. Myocardial perfusion SPECT was done using Tc-99m tetrofosmin (Myoview) after exercise or pharmacological stress and at rest using a standard imaging protocol. Images in the orthogonal body planes and along the heart short and long axis were generated. Data analysis involved projection of the VCG loops after appropriate transformation onto the SPECT images of the myocardium. In addition, a bull’s eye image incorporating the VCG and SPECT data was generated. Conclusion: The coregistration method described provides a novel tool for the evaluation of cardiac electrophysiology and myocardial perfusion SPECT in light of each other thus giving insight into abnormalities encountered in patients especially those with coronary artery disease. The usefulness of the method in various clinical condition is currently being evaluated.

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Poster Presentation

An Accurate Automatic Method For Determination of Left Ventricular Ejection Fraction Using Gated SPECT Perfusion Data

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Automatic quantification of perfusion defect in exercise MIBI SPECT: Comparison between CEqual and AutoQuant measurement in the same subject B.C. Ahn, J. Lee, S.Y. Jeong, S.W. Lee, K.B. Lee. Department of Nuclear Medicine of the Kyungpook National University Hospital, Daegu, South Korea.

P_75

Interstudy repeatability of gated-spect quantitative parameters A.R. Rubio (1), A. Garcia-Burillo (2), J.M. Gonzalez-Gonzalez (1), G. Oller (1), T. Canela (1), J.A. Richart (2), S. Aguade (1), I. Roca (2), J. Castell (1). (1) S. Medicina Nuclear. Hospital Universitari Vall d’Hebron, (2) S. Medicina Nuclear. Centre Medic Delfos, Barcelona, Spain. The aim of the study was to evaluate the interstudy reproducibility of quantitative parameters obtained from myocardial perfusion gated-SPECT studies Methods: Consecutively 58 patients referred to two Nuclear Cardiology units to perform diagnostic or prognostic studies, which accepted this protocol, were included: 27% previous MI, 27% previous myocardial revascularization, 48% angina, 5% left ventricular failure, 60% hypertension. A one-day stress-rest-rest protocol was performed. 150 MBq in stress and 450 MBq at rest were injected. Gated-SPECT images were obtained 30 min after stress, 45-60 min after rest injection (REST1). A second rest acquisition (REST2) were performed 30 min later, after the replacement of patient in the camera. Germano G (QGS®) algorithm was used to obtain EF and left ventricular volumes (EDV, ESV). Two blinded observers processed stress, REST1 and REST2 studies in a randomised order. Paired-t test, regression analysis and Bland-Altman scatter plot was used to evaluate the results. Results: 58 patients completed the stress-rest protocol and 55 had a second rest study. No statistical differences were found between REST1 and REST2 values of EF, EDV and ESV. Correlation (r) and variation coefficient (VC) was:

Aim: Automatic quantification algorithm enables objective assessment of the extent, severity and reversibility of the perfusion defect with lower variability independent of reader skill. There are two commonly used program, CEqual(CE) in which perfusion defect is represented as total percentage occupancy of perfusion defect in LV wall, and AutoQuant(AQ) where data are represented as summed perfusion score by semi-quantitative grading of the segmental perfusion. We have compared quantified perfusion data measured with CE and AQ. Material and Methods: Exercise 99mTc-MIBI myocardial perfusion SPECT was performed in 27 subjects with stable and mild to-moderate degree (50-75% narrowing) single-vessel coronary artery disease(CAD). None has a history of myocardial infarction. Images were acquired with dual-head variable angle camera (Vertex Plus, ADAC) with Bruce protocol. % extent(EXT), severity score(SES) and reversibility score(RES) of the perfusion defect was calculated with CE, and summed stress score(SSS), summed rest score(SRS) summed difference score(SDS) with AQ program without any manual modification. Data were compared between two measurements. Results: Decreased perfusion was demonstrated in 24(89%) of 27 subjects with CE, and 22(82%) with AQ. Adding quantification data did not enhance diagnostic sensitivity of visual analysis (25/27, 92.5%). Positive correlations were observed between EXT and number of segment with perfusion defect (r=0.851), and between SES and SSS (r=0.842). Although RES and SDS were also positively correlated (r=0.786), differences were observed in the individual analysis. Nine subjects (38%) showing SDS>2 on AQ did not show any reversibility on CE (RES=0). Conclusion: Although extent, severity and reversibility of the perfusion defect were well correlated between data measured with CE and AQ, identifying the presence of reversibility was different between two methods. CE could underestimate the degree of reversibility in patients with mild-to-moderate CAD.

Conclusion: High inter-assay reproducibility was observed in quantitative parameters obtained in Gated-SPECT perfusion studies. Therefore, variations in left ventricular functional parameters are confidently attributed to variations in clinical conditions of patients.

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Effect of perfusion defect on automatic quantification of left ventricular mass and functional parameters measured with gated myocardial perfusion SPECT B.C. Ahn (1), J. Lee (1), S.Y. Jeong (1), S.W. Lee (1), H.C. Song (2), H.S. Bom (2), K.B. Lee (1). (1) Department of Nuclear Medicine of the Kyungpook National University Hospital, Daegu, South Korea, (2) Department of Nuclear Medicine of the Chonnam National University Hospital, Kwangju, South Korea, Daegu and Kwangju, Korea. Aim: The presence of perfusion defect in left ventricular wall may affect LV mass(LVM) measurement with quantitative gated myocardial perfusion SPECT(QGS). To evaluate the effect of extent and severity of perfusion defect on the automatic measurement of LVM by QGS, we have compared relationships between LV mass and functional parameters, according to the presence and extent of perfusion defect. Material and Methods: Four hundred ninety nine subjects(M/F=225/273, mean 59yrs) underwent resting QGS with 99mTc-MIBI and echocardiography. Left ventricular(LV) volumes, LV ejection fraction(LVEF), myocardial volume was obtained from QGS by AutoQuant program and LVM was calculated by multiplying the volume by the specific gravity of myocardium. Echocardiographic LVM was obtained with Devereux formula. Results: LVM by QGS was well correlated with those of echocardiography in pts with or without perfusion defect(r=0.627, p<0.01, r=0.853, p<0.01). LVM was positively correlated with LV end diastolic volume, LV end systolic volume and negatively correlation with LVEF in patients either with or without perfusion defect. Extent and severity of total perfusion defect were negatively and weakly correlated with EF(r=-0.317, p=0.049, r=-0.328, p=0.042). EF was negatively correlated with extent and severity of perfusion defect in LV wall of left anterior coronary artery(LAD) territory(r=-0.353, p=0.027, r=-0.350, p=0.029), but not with those of left circumflex or right coronary artery territories. Conclusion: These results suggest that LVM can be measured by QGS in patients with or without perfusion defect in LV wall. LVEF has negatively correlation with extent and severity of perfusion defect in LV wall, especially in LAD vascular territory.

S208

REP1 r REP2 VC (%) EF (%) 57.4 ± 15.0 0.94 54.5 ± 14.0 2.0 ± 5.1 EDV (ml) 104.6 ± 52.6 0.99 110.7 ± 54.9 4.5 ± 8.6 ESV (ml) 51.2 ± 43.8 0.99 56.4 ± 44.7 3.4 ± 6.6 Bland-Altman analysis does not show any significant bias at low or high values.

Correlation between post-stress and rest assessment of left-ventricular function with gated myocardial perfusion SPET M. Mitjavila, M.A. Balsa, L. Gª Cañamaque, F.J. Penín, V. Torres, N. Gambí, C. Pey. Nuclear Medicine, Hospital U.Getafe, Madrid, Spain. Quantitative electrocardiogam-gated SPET myocardial imaging provides functional information of the left ventricle (LV) in addition to myocardial perfusion. The purpose of the study was to evaluate the relationship between the development of perfusion abnormalities and the changes beween left ventricular ejection fraction (LVEF) obtained after stress and at true resting state with gated SPET by using a 2-day stress-rest perfusion function protocol. Patients and method: 2-day imaging stress-rest protocol gated SPET with 99mTc-tetrofosmin was performed in 43 patients (24M, 19F) between 45-80 years old (average age: 63). 15 patients underwent pharmacologic stress (0.56 mg/kg dipyridamole over 4 minutes) and 28 an exercise treadmill test (8 patients failure to achieve 85% of the maximum predicted heart rate, 17 had adequate treadmill exercise). According to perfusion patterns results were classified as normal, 17; infarction, 11; ischemia, 10 and infarction + ischemia 5. The Germano quantitative gated SPET (QGS) software was used to calculate global LVEF, end-diastolic and end-systolic volumes and regional wall motion at post-stress and at resting scan. Results: The average LVEF for post-stress was 52.76% (SD=13.82) and for the rest 50.79% (SD=13.03). The difference between both average was 1.97 (95% of confidence interval= 0.012-3.94). There were no significative statiscal difference between post-stress and rest enddiastolic volume ml neither post-stress and rest end-systolic volume ml. In the dipyridamole test group the average LVEF for post-stress was 55.46% (SD=12.27) and the average LVEF for the rest 53.26% (SD= 11.91). These values did not show significative statistical differences. No significant correlation was found between perfusion pattern and the changes in LVEF from basal to post-stress (p= 0.469). Patients with infarction + ischemia showed greater decline in post-stress LVEF from rest LVEF measurement. Wall motion disturbance were present in 9 patients: 2 in the post-stress study; 2 in the rest study; 3 in both studies and in 2 patients the abnormalities were greater in rest than in the post-stress study. Conclusion: The post-stress left ventricular ejection fraction with stress-rest gated SPET may not represent the true resting LV function. A decrease in LVEF lasting at least 45 minutes post-stress may facilitate the stratification of patients in a subgroup with higher risk, although we have not found a correlation with a perfusion pattern.

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P_79

M.J. Gonzalez (1), Y. Ricart (1), J. Martin-Comin (1), C. Pallares (2), P. Beltran (2), J. Gomez-Hospital (2), A. Cequier (2), E. Esplugas (2), M. Ramos (1). (1) S. Medicina Nuclear,, (2) S. Cardiologia, Hospital Universitari de Bellvitge, (3) Hospital Universitari de Bellvitge, Barcelona, Spain.

F. Dede, Y. Narin. Department of Nuclear Medicine of GATA Haydarpasa Military Hospital, Istanbul, Turkey.

The aim of the study was to compare LVEF, LV volumes and motility index measured by Gated-SPECT versus the values obtained by radiology ventriculography performed within 24 h of Gated-SPECT. Material and methods: 52 patients with coronary artery disease have been studies (mean age 57 years, 35 male). First exam was contrast ventriculography that was followed by rest Gated –SPECT within 24 h. Gated-SPECT was performed 15 min post-injection of 20 mCi of 99mTc-Tetrofosmin. Motility index was scored in both methods : 1: normal, 2: hypokinesia; 3: akinesia; 4: diskinesia. Thickening index was scored in Gated-Spect:1: normal; 2: mild thickening decrease; 3: moderate thickening decrease; 4: absence of thickening. Each index was the ration between the summatory of scores of all segments and the number of segments scored. Results: LVEF mean values were 56.6 ±12.4 and 62.5 ±11.6 with Gated-SPECT and contrast ventriculogarphy respectively. Correlation was statistically significant ( p< 0.001, r: 0.812). The correlation bewteen motility index and between LV volumes were also statistically significant ( p <0,01, r = 0.501 for teledyastolic volume and, r = 0,726 for telesystolic volume). Finally thickening and motility index correlates with LVEF. The correlation was statiscally significant ( p<0,01, r = 0,601 y r =0,657 respectively). In conclusion the measurement of LVEF in Gated-SPECT seems to be an accurate method to evaluate left ventricle function. LVEF with Gated-SPECT are lower than contrast ventriculography.

P_78

Can different software programs give the same functional measurements in ECG gated SPECT: Comparison of two software programs

Aim: Previous studies showed good correlation between Cedars Quantitative Gated SPECT (QGS) and 4D-MSPECT software programs for the calculation of left ventricular function from gated myocardial perfusion SPECT (gSPECT). In this study, we compared both programs for different end diastolic (EDV) and end systolic volume (ESV). Method: Attenuation corrected gSPECT acquisition was performed in 129 cases (stress/rest) who received 740 MBq Tc-99m MIBI. The quantification of EDV, ESV, and ejection fraction (EF) on gSPECT was processed independently with QGS and 4D-MSPECT programs. The measurements from both software were compared each other. Results: 4D-MSPECT gave grater values for EDV, EF and smaller values for ESV (mean differences; + 0,84 ml, +2,7 %, -1,8 ml respectively). Correlation between two software programs for EDV, ESV and EF were excellent overall (r=0,975, 0,984 and 0,94, P<0,0001). The best correlation for EF was found in patients with large (EDV>130 ml, n=16; ESV>65 ml, n=13) left ventricle (r=0,968 and 0,9784 respectively, P<0,0001). Conversely, there was no significant correlation between two programs in small (ESV<15 ml, n=12) hearts (r=0,5517 P=0,0629). Bland-Altman analysis revealed the 95% limits of agreement (2 SDs) for EF were narrower with large (EDV<130 ml; ESV<65) heart (EF: 6,1% and 4,2% respectively) than with small (EDV<55 ml, n=13, ESV<15 ml) heart (EF: 9,8% and 9,2%). Conclusion: QGS and 4D-MSPECT showed excellent correlation overall. However, the patients with large ventricle provide more reproducible EF than with small heart.

P_80

Evaluation of myocardial tracking algorithm to measure ejection fraction with 99mTc-Tetrofosmin gated SPECT: a multicentre study

Accuracy and precision of ejection fraction measurements with 201Tl gated SPECT by means of the Stanford method

E. Itti (1), O. Blagosklonov (2), J. Rosso (1), R. Sabbah (2), P. Guiderdoni (3), J.C. Cardot (2), R. Itti (3), M. Meignan (1). (1) Department of Nuclear Medicine, H. Mondor Hospital/Paris XII University, Creteil, FR, (2) Department of Nuclear Medicine, J. Minjoz Hospital/Franche-Compte University, Besancon, FR, (3) Department of Nuclear Medicine, NeuroCardiologic Hospital/Claude Bernard University, Lyon, France.

E. Evangelista, E. Itti, Z. Malek, S. Desarnaud, J. Rosso, M. Meignan. Department of Nuclear Medicine, H. Mondor Hospital/Paris XII University, Creteil, France.

Aim: Left ventricle ejection fraction (EF) measured with gated SPECT has proven incremental prognosis value for coronary artery disease (CAD) but image processing algorithms tend to underestimate high EF values. After previous validation of a new algorithm, based on dense motion field tracking (MyoTrack, INRIA, FR) with 201Tl, we aimed to evaluate this method with 99mTc-labeled agents. Material and Methods: We studied 100 patients with low-to-medium probability of CAD and referred for a diagnosis assessment in three nuclear medicine centres. Patients underwent post-stress (70% exercise, 30% dipyridamole) and resting gated SPECT acquisitions using one single-head and four dual-head cameras. Images were transmitted in Interfile format for centralised processing. EFs were calculated using Germano’s algorithm (QGS) and the new MyoTrack program (MTK). Briefly, the originality of the latter resides in the segmentation method, generation of 3D ellipsoids, dense motion field tracking of the ellipsoid nodes throughout the eight phases of the cardiac cycle and intensity continuity constraints. Results: Using QGS, EF values at stress and at rest averaged 54 ± 11% and 56 ± 11%, respectively. By contrast, EF values measured by MTK were significantly higher 61 ± 9% (p < 0.001) and 63 ± 8% (p < 0.001), respectively. Linear regression between QGS and MTK showed r coefficients > 0.85. Differences between QGS and MTK EF values progressively increased in the higher EF ranges. Conclusion: Myocardial tracking algorithm shows good accuracy for EF calculation with 99m Tc gated SPECT, compared to conventional QGS method, in various imaging systems. Moreover, MTK is less subject to underestimation of high EF values, as previously shown with 201Tl.

Aim: Left ventricular ejection fraction (LVEF) is essential for the prognosis of coronary artery disease and can be assessed by 201Tl gated SPECT. We evaluated accuracy and precision of the Stanford (SegamiTM) method for LVEF measurement in severe cardiac patients. Materials and Methods: Seventy five patients with extensive myocardial infarction underwent a rest (20 min) and redistribution (4 h) 201Tl gated SPECT viability protocol, followed immediately by a 99mTc equilibrium radionuclide angiography (ERNA). Quality of SPECT images was evaluated both from the count statistics and from the extent of perfusion defects. LVEFs at 20 min and 4 h were calculated with the Cedars-Sinai algorithm (QGS) and with the Stanford method (STA). Briefly, the latter relies on the analysis of radial count profiles and uses the first moment (radial motion) and the second moment (wall thickening) to determine the outlines of the endocardial surface and further calculates LVEF from volume computation. Results: QGS significantly underestimated ERNA LVEF values (p < 0.001), particularly for high ERNA LVEF ranges and in relation to the temporal undersampling of the 8-frame acquisition. By contrast, no underestimation was found with STA (p = NS, see Table 1), except in cases of ERNA LVEFs > 50%. Repeatability between 20 min and 4 h was higher with QGS (r = 0.90) than with STA (r = 0.73). Differences between 20 min and 4 h or between ERNA and SPECT were not correlated to the extent of perfusion defects or count statistics. Conclusion: STA method shows satisfying accuracy for LVEF calculation with 201Tl, compared to ERNA, but repeatability of measures appears to be lower, compared to QGS, independently of technical conditions of acquisition. Table 1. Correlation between ERNA (LVEF = 33 ± 14 %) and gated SPECT

LVEF (%) r coefficient

QGS 20 min 30 ± 13 0.86

QGS 4 h 30 ± 13 0.90

STA 20 min 34 ± 15 0.78

STA 4 h 34 ± 16 0.84

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Poster Presentation

LVEF, motility index and LV volumes. Gated-SPECT versus ventriculography performed within 24 hours.

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Comparison of left ventricular function at rest and post-stress Tc99m MIBI gated SPECT in normal and ischemic myocardium F. Dede, Y. Narin. Department of Nuclear Medicine of GATA Haydarpasa Military Hospital, Istanbul, Turkey. Aim: Myocardial Tc-99m MIBI ECG gated SPECT (gSPECT) is one of the cardiac imaging modality which provides functional information of left ventricle and myocardial perfusion. However, the variation of the functional information between post-stress and rest studies are not well understood. In this study, we investigated whether 1-hr post stress gSPECT revealed changes induced by stress in ischemic and non-ischemic myocardium. Method: 63 patients (29 women, 34 men, mean age; 56±13 y) underwent two-day stress-rest protocol and attenuation corrected Tc-99m (740 MBq) gSPECT sampled at 8 frames/cycle RR. From these images; left ventricular ejection fraction (LVEF), and end-diastolic volume (EDV) were calculated by 4D-MSPECT software. For statistical evaluation, GraphPadInStat3 program was used. Results: No significant differences in LVEF were observed between 1-hr post stress and rest in non-ischemic group (n: 48, mean of paired differences [MPD] = + 1,17 %, P > 0,05). Conversely, ischemic group (n: 15) showed significantly reduced 1-hr post stress LVEF (MPDs= - 4,92 %, P < 0,001). In non-ischemic group, EDV on the post-stress gSPECT was significantly smaller than that of rest gSPECT (MPDs= - 6,92 ml P < 0,001). However, there was no significant change between post stress and rest gSPECT in ischemic group (MPDs= + 1,67 ml, P > 0,05). Conclusion: Functional information obtained from 1-hr post stress gated SPECT did not show exact resting conditions in neither normal nor ischemic cases. Therefore, 1-hr post stress gSPECT is unsuitable to assess resting function.

P_83

Role of gated myocardial perfusion SPECT and bidimensional echocardiography in the evaluation of left ventricular volumes and ejection fraction in patients with coronary artery disease: a comparison with contrast left ventriculography C. Cittanti (1), E. Succi Leonelli (2), M. Giganti (1), P. Colamussi (1), G. Percoco (2), D. Mele (2), A. Filice (1), S. Panareo (1), A. Piffanelli (1). (1) Section of Nuclear Medicine of the University of Ferrara, Ferrara, Italy, (2) Section of Cardiology of the University of Ferrara, Ferrara, Italy. Aim: In patients suffering from coronary artery disease the accurate assessment of left ventricular volumes and function has major diagnostic, prognostic and therapeutic implications in particular after myocardial infarction and in subjects prone to heart failure. Even though many instrumental approaches are available for this purpose, it is important to know whether the results of these independent techniques are really interchangeable in the clinical practice. Aim of this study was the evaluation of the concordance of left ventricular volumes and ejection fraction (LVEF) assessed by gated myocardial perfusion tomography (GS) and bidimensional echocardiography (EC) in comparison with contrast left ventriculography (LVG) in patients with chronic CAD. Methods: Forty-seven patients (39M; 8F – mean age 57±15yr) with ischemic heart disease underwent clinically indicated GS, EC and LVG within a 15 days period. End systolic volume (ESV), end diastolic volume (EDV) and LVEF values were assessed from rest 99mTc-sestamibi GS using a commercially available software (QGS) from EC by a standard Simpson’s biplane analysis and from LVG by a single plane modified Dodge’s method. Results: LVEF evaluated with GS (56.6±10.5%) and EC (55.8±11.5%) were significantly lower than LVG values (62.0±11.4%). Pearson’s correlation coefficients and Bland-Altman (BA) ranges were respectively 0.91 and less than 2SD for GS and 0.79 and about 3SD for EC. No significant statistical differences were noticed in ESV estimates whereas EDV showed lower values for both GS and EC in comparison to LVG. Finally GS vs LVG demonstrated higher correlation coefficients and lower BA ranges for both EDV and ESV in comparison to EC. Conclusion: While ESV estimates were substantially comparable with all the three techniques, both GS and EC seem to provide a significant underestimation of LVEF and EDV in comparison to LVG; moreover probably due to a less operator independence, BA limits of agreement were significantly higher for EC in comparison to GS. Our data suggest that these images techniques provide different and not interchangeable estimates of the same physiologic parameters so that serial assessment of left ventricular function with various instrumental approaches should be carefully performed. Larger prospective trials are needed to confirm our preliminary findings and to evaluate their possible impact in the clinical practice.

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P_84

CL. Petersen, A. Kjær, AM. Hviid. Department of Nuclear Medicine, Frederiksberg Hospital H:S, Copenhagen, Denmark.

K. Muylle, C. Vanhove, A. Maenhout, P.R. Franken. Department of Nuclear Medicine of the Free University Brussels.

Aim: To evaluate the diagnostic gain from gated SPECT by determination of end diastolic volume (EDV), end systolic volume (ESV) and stroke volume (SV) of left ventricle in rest as well as stress perfusion studies in patients with suspected ischemic heart disease. Materials & methods: Consecutive patients (n=140) suspected of ischemic heart disease were included in the study (89 males, 51 females, mean age 72 years). On different days rest and stress gated myocardial perfusion SPECT with the sestamibi tracer were performed. Stress procedure was based on either physical exercise, dobutamine- or dipyridamole infusion according to international standards. On a dedicated dual head gamma camera gated acquisition with 8 frames per cardiac cycle was performed. Tomographic reconstruction and post processing with determination of left ventricular volumes and perfusion was done with standard software. Results: (All values are mean).

Aim: The purpose of this study was to compare 180- versus 360-degree data acquisition on left ventricular end-diastolic volume (EDV) and left ventricular ejection fraction (LVEF) measured by gated myocardial perfusion tomography (gMPT) and gated blood pool tomography (gBPT). Materials and Methods: Twenty patients with a history of myocardial infarction were injected in a random sequence with 740 MBq of Tc99m human serum albumin and within 2 days with 925 MBq of Tc99m-tetrofosmin. gMPT and gBPT were acquired on a 3-head gamma camera equipped with LEHR collimators. Parameters were: 360-degree rotation, 96 projections, 64x64 matrix, 5.79mm pixel size; 30 sec per stop and 8 time-bins. Projection images were reconstructed using the 360-degree data and again using only data acquired from LPO to RAO. Projection data were reconstructed by filtered backprojection using a Butterworth filter order 5 (cut-off 0.44 cycle/cm for gMPT and 0.35 cycle/cm for gBPT). After the reorientation of the images according to the left ventricular long axis, LVEF and volumes were calculated using 4 fully automatic programs (QGS and 4DMSPECT for gMPT; QBS and QUBE for gBPT). Results: The 180-degree perfusion data could be analysed correctly in all patients with QGS and 4DMSPECT. The 180-degree blood pool data however could not be analysed correctly in 5 patients with QBS and in 5 patients (4 of which were the same) with QUBE. The linear correlation coefficient (r), standard error of the estimate (s.e.e.) and mean difference between 180- and 360-degree acquisition are given in Table. (*) indicates p<0.05 (t distribution).

Substantial difference in left ventricular architecture and perfusion can occur despite unchanged stroke volume.

PERFUSION DEFECT

EDV Rest (ml) 97

ESV Rest (ml) 51

SV Rest (ml) 46

EDV STRESS (ml) 97

no defects - rest + reversible stress 101** 53 48 101** + rest + reversible stress 144** 94** 50 149*/** + rest - reversible stress 172** 118** 54 171** *) p<0.05 (change from rest to stress, paired observation). **) p<0.05 (difference between groups, unpaired observation).

ESV STRESS (ml) 50

SV STRESS (ml) 47

53

48

98*/**

51

117**

54

Conclusion: Significant difference in volumes and perfusion can take place in the left ventricle despite unchanged stroke volume from rest to stress. The “ischemic burden” of left ventricle is reflected in increased left ventricular EDV and ESV in different groups of patients, although stroke volumes are equal in the groups.

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Comparison of 180-degree and 360-degree data acquisition in gated myocardial perfusion and in gated blood pool tomography

EDV gMPT (n=20) 4DM QGS Correlation coeff. r 0.99 0.99 * Mean diff. (%) -7.8 3.4* s.e.e. (%) 5.8* 4.3*

gBPT (n=15) QUBE QBS 0.87 0.95 -15.9* -10.5* * 16.2 11.1*

LVEF gMPT (n=20) 4DM QGS 0.93 0.98 * 7.8 0.3 13.4* 7.8

gBPT (n=15) QUBE QBS 0.92 0.92 8.6* -0.5 * 11.9 16.2

Conclusions: The acquisition can be limited to the 180-degree data for measuring EDV and LVEF from gated myocardial perfusion tomography, especially with the QGS algorithm. However, 360-degree data acquisition is recommended when measuring EDV and LVEF from gated blood pool tomography.

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n GATED PERFUSION SPECT - METHODOLOGY The comparison of adenosine exercise Tc-99m tetrafosmin with treadmill MIBI gated SPECT M. Dziuk (1), A. Canizales (2), K.E. Britton (2), J. Pietrzykowski (1), M. Cholewa (1). (1) Central Hospital Military Medical School, Warsaw, Poland, (2) Department of the Nuclear Medicine of the St. Bartholomew’s Hospital, London, UK. The comparison of adenosine exercise tetrafosmin with treadmill MIBI gated SPECT Aim: The effect of adenosine and stress on stress-rest tetrafosmin and exercise GSPECT left ventricular ejection fraction (LVEF), end diastolic volume (EDV) and end systolic volume (ESV) values has not been fully investigated. The aim of the study was to compare GSPECT LV function measurements obtained in two different protocols: one-day adenosine rest and two-day stress-rest. Material and Methods: We examined 126 consecutive patients (group 1) with submaximal treadmill stress-rest 700 MBq Tc-99m MIBI gated SPECT and 26 patients (group 2) with adenosine (140 ?g/kg/min) enhanced by a low level exercise gated SPECT (300 MBq and 700 MBq Tc-99m tetrafosmin for stress and rest respectively). All images were acquired on a double head system after 1 hour post injection and were gated using 8 frames, 25s per frame. Twenty six subjects from group 1 with the same characteristics: age, sex, weight, prior myocardial infarction, pre-test probability, rest LVEF and rest EDV, were selected to match the patients from group 2. Results: In general the ED and ES volumes increased after adenosine but decreased after true stress resulting in the treadmill stress LVEF being significantly greater than in adenosine group 60+/-11 vs 51+/-13% (P<0.01). The above was caused predominantly by the poststress end systolic volume being significantly smaller in the treadmill group 40+/-20 vs 51+/-34 P<0.05. The differences of LVEF, EDV and ESV between poststress and rest were significantly different (P<0.0001) in studied groups. We found that in both groups the perfusion data showed significant reversible myocardial ischaemia in 14 cases. In negative scans the GSPECT analysis showed greater LVEF (61+/-8 vs 51+/-14 P<0.01) and smaller ED and ES volumes (P<0.03) both after stress and at rest. The EDV and ESV values tend to be larger in positive perfusion scans. Conclusion: In the gated SPECT myocardial perfusion scans showing ischaemia the end diastolic and end systolic volumes appear to be greater than in negative studies. The adenosine stress test may have opposite influence on the EDV and ESV in comparison to the submaximal treadmill test and therefore the left ventricular function measurements after adenosine infusion should be interpreted carefully may not represent those acquired after physical exercise.

P_86

Simultaneous evaluation of systolic and diastolic regional functions with quadruple contours display method using ECG-gated myocardial SPECT M. Harada (1), A. Shimizu (2), M. Murata (1), M. Kubo (1), R. Mitani (1), Y. Dairaku (1), M. Matsuzaki (1). (1) division of cardiovascular medicine, yamaguchi university school of medicine, (2) faculty of health science, yamaguchi university school of medicine, Ube, Japan. Aim: As the systolic dysfunction is preceded by the diastolic dysfunction in patients with myocardial ischemia , it is thought that diastolic parameter is more sensitive for the detection of myocardial ischemia than systolic parameter. The purpose of this study is to establish the method for measuring systolic function and diastolic function simultaneously and semi-quantitatively with quadruple contours display (QCD) method using ECG-gated exercise myocardial SPECT in the patients with ischemic heart disease and whether QCD method is clinically useful for the detection of myocardial ischemia. Materials and Methods: ECG-gated exercise myocardial SPECT using Tc-99m myocardial perfusion agents and coronary angiography were performed on 44 consecutive patients with suspected ischemic heart disease (38 males, 6 females; age 63±11 years old; 26 patients of myocardial infarction, 8 patients of angina pectoris and 10 patients of normal). The SPECT images were obtained at 30 minutes after injection of Tc-99m agents during exercise (296MBq) and at rest (740MBq) respectively. Epicardial and endocardial surfaces in enddiastole, endocardial surface in early one-third of diastolic period and endocardial surface in end-systole were automatically drawn by QGS program. QCD was produced by superimposing these surfaces with personal computer. Left ventricle excluding interventricular septum was divided into 7 segments in RAO view and LAO view, the grade of systolic wall thickening and early one-third diastolic filling on each segment was visually scored from normal (3 point) to decline (0 point), systolic score (SS) and diastolic score (DS) were defined respectively. The culprit lesion was estimated from SS and DS after exercise and them at rest, it was compared with coronary angiography findings. Results: Concerning the sensitivity of detection for culprit lesion of coronary artery disease, DS after exercise was 96%, DS at rest was 93%, SS after exercise was 82%, and SS at rest was 73%. While as for the specificity, SS at rest was 100%, SS after exercise was 96%, DS at rest was 89%, and DS after exercise was 80%. The lesion had a tendency to be underestimated by SS and to be overestimated by DS. Conclusion: Regarding the sensitivity of detection for myocardial ischemia with QCD method, diastolic parameters were superior to systolic parameters in the regional left ventricular function, but systolic parameters were superior to diastolic parameters conversely as for the specificity.

P_87

Left ventricular ejection fraction and volumes in coronary patients. Correlation and agreement between gated SPECT and equilibrium isotopic ventriculography. I. Casáns-Tormo (1), J. Ferrer (1), A. Llácer (2). (1) Nuclear Medicine. Hospital Clínico Universitario, (2) Cardiology. Hospital Clínico Universitario, Valencia. Spain. Aim: To assess the accuracy of left ventricular ejection fraction (EF) and volumes measurement by gated SPECT (GSPECT), we have studied 36 coronary patients proven by coronary angiography, with mean EF 35.3+17.9% (10-71), 21 of them with EF<35% and the other 15 with EF>35%. Methods: SPECT myocardial perfusion was obtained with 99mTc-Tetrofosmin (2 day-protocol), with gated acquisition always 1h after tracer injection administered at rest (8 frames/cycle, 64x64, 60 images, 25 s/image), with EF and volumes measurement by QGS program. An equilibrium isotopic ventriculography (EV) was obtained 48 h later, with EF determination by usual non-geometric semiautomatic method and volumes by Massardo method. All studies showed suitable quality for quantification. We have assessed differences in mean EF and volumes values, correlation and agreement (Bland-Altman analysis) between the two methods. Results: Considering all patients, we have found high correlation in EF, end-diastolic (EDV) and end-systolic volumes (ESV) determination between EV and GSPECT (r: 0.95, p: 0.0001; r: 0.91, p: 0.0001; r: 0.97, p: 0.0001, respectively), although by EV mean EF was higher (35.0+18.8%, 32.1+17.1%) and mean ESV lower (122.6+74.0%, 132.0+78.4%) than by GSPECT (p<0.01). In patients with EF>35%, the correlations were good (r: 0.81, p: 0.001; r: 0.75, p: 0.004, and r: 0.82, p: 0.001, in EF, EDV and ESV), as well as in the group with EF<35% (r: 0.80, r: 0.85 and r: 0.94 respectively, p: 0.0001 in all cases). Mean difference and limits of agreement between both methods were:

EF EDV ESV

Group with EF>35% mean difference limits of agreement 19.2 to –9.6 4.8+7.2 16.5+18.7 53.9 to –20.9 0.8+12.2 25.2 to –23.6

Group with EF<35% mean difference limits of agreement 1.6+3.8 9.2 to 5.9 -15.2+31.4 47.6 to -78 -16.2+18.8 21.4 to –53.8

Conclusion: Good correlation and agreement was found between gated SPECT and equilibrium ventriculography in EF determination, in patients with higher as well as lower EF, with agreement even better in the group with lower EF. Ventricular volumes assessment showed good correlation and agreement between both methods, although the limits of agreement were wider in the patients with lower EF. So, gated SPECT provides as accurate quantification of EF and ventricular volumes in coronary patients as equilibrium ventriculography, but the agreement between both methods in volumes determination could be lower in patiens with ventricular dysfunction.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition GATED PERFUSION SPECT - CLINICAL

P_88

Efficacy of stress-rest 99mTc-MIBI myocardial SPET in the prediction of contractile recovery after revascularization. J.M. González (1), M. Ysamat (1), M. Buxeda (1), J. Castell (2), S.Aguadé(2), J. Candell (2). (1) Centro de Tecnología Diagnóstica, Terrassa, SPAIN, (2) Hospital Universitari Vall d¨Hebron, Barcelona, Spain. The aim of this study was to evaluate the efficacy of stress-rest methoxi-isobutil-isonitriletechnetium-99m (99mTc-MIBI) to predict wall motion improvement after revascularization. Material and methods: 82 patients (59 +/- 9 years, 12 women), who had some segment with severe impairment of the contractility and underwent coronary revascularization by surgery (64) or angioplasty (18) were studied with rest 99mTc-MIBI SPET. Stress test was also performed to 40 of these patients. Before and within 3 – 6 months after revascularization a three projections gated blood pool scintigraphy was performed. The segmentary contractile recovery after revascularization was assessed in relation to the quantification of rest 99mTc-MIBI uptake and the stress-rest reversibility (stress uptake < rest uptake). Results: The mean value of the ejection fraction did not change after revascularization ( 41 +/- 14 vs 42 +/- 16). In the post revascularization control a contractile recovery was observed in 47% (151/318) of the segments with severe hypokinesia, akinesia or dyskinesia. Rest uptake >30% were present in 92% (p < 0.0001) of segments that improved contractility after revascularization. In the 40 patients who underwent stress-rest test, 80 segments improved contractility after revascularizarion: 50 segments (63%) were present reversibility and 30 segments (37%) no reversibility (p < 0.0001). Conclusions: For the 99mTc-MIBI SPET an rest uptake > 30% and stress –rest reversibility are criteria of contractile recovery after revascularization.

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Role of the Gated-SPECT functional markers for viability assessment in patients with severe left ventricular dysfunction

Value of post-stress Sestamibi lung uptake and ventricular dilation by Gated-SPECT in severe ischemia

M. Garcheva (1), J. Jorgova (2), D. Trendafilova (2), I. Kostadinova (1). (1) Clinical Center of Nuclear Medicine and Radiotherapy, Medical University, Sofia, Bulgaria, (2) Clinic of Cardiology and Cardiac Surgery, Sofia, Bulgaria.

C.M. Marcassa, R. Campini, P. Calza, M. Galli, O. Zoccarato, P. Giannuzzi. S. Maugeri Fnd, Scientific Inst. of Veruno, Cardiology and Nuclear Medicine Depts, Veruno.

The results showed: a good correlation of the severe perfusional and functional changes; preserved motion of almost all segments with uptake ≥50%; 9 segments with uptake <50% had functional markers of viability (7 - preserved motion and 2 - preserved thickening). Conclusion: The functional markers from Gated-SPECT had a complementary role for the assessment of myocardial viability in patients with severe left ventricular dysfunction.

Background. On thallium-201 scintigraphy, supplementary sign of ischemia (i.e. transient ischemic dilation (TID) and high lung/heart ratio (L/H)) have been correlated to the severity of ischemia. The value of these parameters at stress sestamibi SPECT imaging is less established. Methods. We studied 360 consecutive pts (63+9 years; 53% male) with known or suspected CAD (22% with previous MI), undergoing dual-day stress (187 pts exercise and 173 dipyridamole) - rest sestamibi Gated-SPECT imaging. L/H was calculated from a summed anterior projection on post-stress images; the perfusion defect size was calculated from polar maps of tracer distribution by comparison with our normal data-base (mean – 2SD): stress-induced ischemia was defined as a (stress – rest) tracer uptake defect >5% of LV surface. Post-stress and rest LV EF and volumes were automatically calculated using the QGS method; a TID index was calculated as post-stress/rest EDV ratio. Severe ischemia was defined as the presence of either a reversible defect>15% or a decrease in LVEF from rest to stress >5%, or both. Results. Reversible perfusion defects were documented in 100 pts (28%); severe ischemia was documented in 48/100 pts (48%; 25 with a reversible defect>15%, 14 with a LVEF decrease >5% and 9 with both) . L/H was .36+.06 and .29+.05 in pts with or without severe ischemia, respectively (p<0.0001). TID index was 1.08+.22 and 1.37+.45, respectively, in pts with or without severe ischemia (p<0.001). By ROC analysis, L/H better correlated with the occurrence of severe ischemia (area-under-curve 0.81 [CI 0.76-0.92]; sensitivity 79%, specificity 89%) than TID index (area-under-curve 0.72 [CI 0.61-0.81], sensitivity 59%, specificity 83%; p<0.05). The best cut-off values of L/H and TID index for the detection of severe ischemia were 0.32 and 1.19, respectively. Conclusions. An elevated (>0.32) L/H on post-stress sestamibi SPECT seems to yield good accuracy in the detection of patients with severe ischemia, superior to that provided by TID.

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P_92

G. Storto (1), W. Acampa (1), W. He (1), T. Pellegrino (1), A. Sorrentino (1), L. Spinelli (2), A. Cuocolo (1). (1) Department of Biomorphological and Functional Sciences, University Federico II, Napoli, Italy, (2) Department of Internal Medicine, Cardiology and Heart Surgery, University Federico II, Napoli, Italy.

M. Dziuk (1), M. Zachorski (1), J. Pietrzykowski (1), H. Rdzanek (2), J. Jezierski (2), M. Cholewa (1), L. Kubik (1), E. Dziuk (1). (1) Central Hospital Military Medical School, Warsaw, Poland, (2) Department of Invasive Cardiology of the Central Hospital MSWiA, Warsaw, Poland.

Aim: to determine the role of the preserved systolic thickening (Th) and wall motion (WM) in the infarct related perfusion defect area. Materials and methods: SPECT and Gated-SPECT examinations were performed in 13 patients with severe left ventricular dysfunction (ejection fraction 33.5%±7.6% from echocardiography) after myocardial infarction. Tc-99m sestamibi in rest and post-nitrates (20 mg ISDN) was applied. Tc-99m sestamibi uptake was assessed quantitatively as≥50%, or <50%, accepted as cut-off of viability. The wall motion and systolic thickening were determined qualitatively in corresponding vascular territories as preserved (pr) and reduced (red). Results: From 124 segments, involved in the infarct related perfusion defect, 108 were with uptake <50% and 16 (12%) - with uptake ≥50% (at rest, or after nitrates). All segments with markers of viability were 25 (20%). Uptake≥50% Th pr Th red WM pr WM red n=16 n=9 n=7* n=15 n=1 Uptake<50% Th red Th pr WM red WM pr n=108 n=104 n=4 n=101 n=7 *5/7 of the segments with reduced thickening reached uptake ≥50% after nitrates.

Impact of regional wall thickening by gated cardiac tomography in predicting functional recovery after coronary revascularization in patients with ischemic left ventricular dysfunction

Noninvasive assessment of myocardial viability is useful for clinical decision-making in patients with ischemic left ventricular (LV) dysfunction. This study was designed to determine the capabilities of gated single photon emission computed tomography (SPECT) wall thickening in detecting myocardial viability in patients with previous myocardial infarction and impaired LV function. Methods: We studied 24 patients (3 women and 21 men, mean age 50±10 years) with documented myocardial infarction and LV dysfunction (LV ejection fraction 42±6%). In all patients baseline studies included echocardiography, rest Tc-99m sestamibi gated tomography and coronary angiography. On gated SPECT, regional sestamibi uptake was quantitatively measured in 13 segments/patient and wall thickening was assessed in corresponding segments. Within one month from baseline study, all patients underwent coronary revascularization (coronary artery by-pass grafting in 13 and percutaneous transluminal angioplasty in 11 patients). Echocardiography was repeated 8 months after revascularization to evaluate recovery of LV function. Results: After revascularization, LV ejection fraction increased from 42±6% to 49±7% (p<0.001). Of the 82 akinetic or dyskinetic segments at baseline, 50 (61%) showed functional recovery (viable segments) and 32 (39%) did not change (nonviable segments) after revascularization. Regional sestamibi activity was higher in viable as compared to nonviable segments (66±15% vs 53±18%, respectively, p<0.01). Among the 50 viable segments, apparent wall thickening on gated SPECT was detectable in 20 segments (positive predictive value of 67% for wall thickening to predict functional recovery). Among the 32 nonviable segments, no apparent wall thickening was present in 22 segments (negative predictive value of 42% to predict absence of functional recovery). Sestamibi uptake was significantly reduced in akinetic or dyskinetic segments demonstrating functional recovery after revascularization and no apparent wall thickening as compared to those with preserved wall thickening (60±15% vs 71±13%, respectively, p<0.001). Conclusions: In patients with ischemic LV dysfunction, preserved wall thickening on gated SPECT correlates with functional recovery after revascularization. However, the absence of apparent wall thickening underestimates the presence of viable myocardium in dysfunctional segments with severe reduction of sestamibi uptake.

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Tc-MIBI gated SPECT perfusion and function return in patients subjected to primary PTCA - 6 month follow-up results in comparison to early studies

Aim: Gated SPET is the only modality that gives reliable results about perfusion and function of the myocardium and may serve for the follow-up tool after percutanous coronary angioplasty treatment of the acute myocardial infarction.The aim of the study was to assess the ability of ECG gated SPET with Tc-99m-MIBI in determining the benefits for patients after primary PTCA. Material and Methods: Fifteen patients with acute myocardial infarction (7 anterior, 8 inferior) were subjected to PTCA with stenting of the infarct related artery within 6 hours from the onset of chest pain. After 6 days they were studied by means of the ECG gated SPECT at rest with Tc99m MIBI 740 MBq and after 10 days they underwent same dose stress myocardial perfusion study with gating after exercise treadmill test. Both sets of images were acquired 1 hour post injection with a double head system, 8 frames per cycle, 25 second per frame. The above sequence was repeated after 6+/-1 months. The regional perfusion, wall motion disturbance, left ventricular ejection fraction, LVEF and end diastolic and end systolic volumes, (EDV, ESV) were assessed both poststress and at rest. Results: When we compared the studies obtained early after coronary intervention and at 6 months in 10 patients (67|%) the perfusion improved in the infarct area. The recovery of regional wall motion disturbances was observed in 14 patients (93%). The left ventricular function measurements are presented in the table below. LVEF LVEF EDV EDV ESV ESV

at rest after stress at rest after stress at rest after stress

unit % % ml ml ml ml

PTCA 52+/-12 50+/-13 110+/-30 109+/-29 55+/-27 60+/-23

6 months 56+/- 11 50+/-13 102+/-38 101+/-21 49+/-25 55+/-28

P value <0.03 <0.05 NS <0.05 <0.05 <0.02

Conclusion: The regional perfusion and wall motion in gated SPECT may improve after 6 months post PTCA of the infarct related artery. The global left ventricle ejection fraction may increase and the ESV and EDV decrease both after stress and at rest. Rest stress gated SPECT can assess the the short term and 6 month efficacy of the procedure in patients with acute myocardial infarction treated with primary PTCA and therefore may serve as a valuable follow-up modality.

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C.T. Mesquita (1,2,3,4), M.C.P. Pessoa (3), P.P. Vasconcelos (3), A.C. Oliveira (1), A.G. Reis (4), H.F.R. Dohman (1), L.M.B. Fonseca (1,2,3). (1) Hospital Procardiaco, (2) Universidade Federal do Rio de Janeiro, (3) Pro-echo, (4) Hospital São Lucas, Rio de Janeiro, Brazil.

S. Fukuzawa, S. Ozawa, M. Inagaki, K. Shimada, J. Sugioka. Division of Cardiology, Funabashi Municipal Medical Center, Chiba, Japan.

Comparison between Myocardial Washout Ratio of Tc-99m MIBI and Left Ventricular Remodeling in Patients with Acute Myocardial Infarction

Aim: The purpose of this study was to evaluate the reliability of the measured left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volumes (EDV, ESV) by the electrocardiographically (ECG) gated myocardial perfusion single-photon emission computed tomography (gated SPECT) in patients submitted to coronary artery bypass surgery (CABG). Material and Methods: we compared technetium-99m sestamibi ECG-gated SPECT imaging with magnetic resonance imaging (MRI) in the assessment of left ventricular function in 20 patients in the first year after CABG and in 20 healthy volunteers. The Cedars Sinai QGS software was used to evaluate left ventricular function in ECG-gated SPECT studies. Results: There was moderate to good correlation between ECG-gated SPECT and MRI in the healthy volunteers in respect of LEVF (r = 0,53; p = 0,01), ESV (r = 0,73; p = 0,0002) and EDV (r = 0,85; p = 0,0001). In the post-CABG patients the correlation was good for LEVF (r = 0,85; p =0,0001), moderate for ESV (r = 0,63; p = 0,003) and not significant for EDV (r = 0,31; p = 0,2). Conclusion: These results suggest that the evaluation of left ventricular function with ECGgated SPECT may be less reliable in patients after CABG.

Background: Some laboratory studies have reported that the accumulation and clearance kinetics of Tc-99m MIBI are significantly affected by cell viability. Tc-99m MIBI kinetics appear to be dependent on sarcolemual integrity and to a lesser extent on aerobic metabolism. This study was designed to compare myocardial mitochondria injury and the recovery stage of left ventricular (LV) function in patients with acute myocardial infarction (AMI) undergoing primary angioplasty. Materials and Methods : Initial and delayed planar scanning were determined in 24 patients who underwent Tc-99m MIBI resting gated SPECT within 7 days (early stage) of admission due to AMI. A washout ratio (WOR) was calculated from the initial and delayed raw data images. Resting gated SPECT was performed on each patient 6 months (recovery stage) after AMI. Gated SPECT measurements for LV end-diastolic volume index (EDVI), end-systolic volume index (ESVI) and LV ejection fraction (EF) were obtained. Results: The mean WOR of all subjects was 42.6 +- 13.8 % . No significant relationship was seen between WOR and EDVI, ESVI, EF of each stage, whereas WOR was significantly correlated with LV dilatation in recovery stage [recovery stage EDVI – early stage EDVI] (R= 0.62, p<0.05). Conclusions: Our data show that the WOR information in early stage predicts the recovery stage of LV remodeling after AMI. We suggest that Tc-99m MIBI kinetics may be associated with mitochondria in energy depend manner as a free cationic complex.

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P_96

G.C. Cantinho (1,2), H.P. Pena (1,2), J.M. Monteiro (1), A.M. Marques (1,2), S.F. Figueiredo (1), F.G. Godinho (1,2). (1) Atomedical, Lab. Medicina Nuclear, Lisboa, Portugal., (2) Faculdade de Medicina de Lisboa, Lisboa, Portugal.

E. Safonova, E. Zharova, V. Sergienko, L. Samoylenko. Cardiology Research Center, Moscow, Russia.

LV Mass and Chamber Volume in Dilated Cardiomyopathy (DCM)

Aim: To evaluate the relation between the mass of LV wall, chamber volume and the degree of LV dysfunction, in patients with DCM. Materials and Methods: we studied 22 patients (pts) with confirmed dilated cardiomyopathy, 16 males, 6 females; mean age: 60±9 y. All the pts were submitted to 99mTc-Tetrofosmin, in a total dose of 40 mCi. Dipyridamole stress gated SPECT was performed after rest acquisition. The studies were performed in an ADAC Vertex gama-camera. Results were obtained by qualitative and quantitative analysis, based on Germano’s algorithm. A normal population is used as a control reference database for quantitative values. Quantitative values were obtained for perfusion (QPS) and LV function (QGS), with obtention of quantitative parameters of severity (scale 1-10), extension (1-10), reversibility (%), EF (%), wall mass (ml) and chamber volume (ml) Results: All the 22 patients had normal perfusion studies. However, the quantification of QPS revealed slight alterations, depending on the degree of the dilation, which is the cause of the great standart deviation obtained when the mean values were calculated. Perfusion results: mean reversibility: 38.9±68.7; mean severity: 1.2±10.7 and mean extension: 4.3±7.4. Functional gated results: EF: 47.5±8.7; EDV: 154±20ml; MassRest: 173.4±16.6; MassStress: 178.9±17. Chamber at rest and stress, non-gated: Stress: 123.2±20.6; Rest: 121.6±23. Normal perfusion results: Severity: 0.44±0.5; reversibility 10.34±33.7; Extension: 1.1±3.9. Functional results: EF: 66.4±7.3; EDV: 77±23.8; MassRest: 116.8±20.6; MassStress: 117.9±25.9; Chamber Rest: 52.7±19.9; ChamberStress: 52.2±18.8. Conclusions: 1. Heterogeneous results of QPS are related to the degree of dilation; however, it helps us in the analysis of perfusion studies in patients with DMC, to rule out CAD. 2. There is no difference between mass and chamber volume at rest and stress. 3. The relation of EF / EDV / Mass shows that the more severe the dilation, the higher the mass and lesser the EF. When compared to a reference normal population, we may conclude that the volume of LV chamber and its mass wall increase, as the EF decreases.

Assessment of the effects of diltiazem-induced heart rate decrease on myocardial perfusion and contractility in patients with coronary heart disease using 99mTc-MIBI gated SPECT

AIM: To assess the effects of diltiazem - induced rate decrease on myocardial perfusion (MP), systolic and diastolic function in patients with chronic coronary artery diseas? (CAD) and mildly depressed myocardial contractility. METHODS: 26 males (mean age 57 +7 yrs) with stable angina (20 pts with CCS functional class 2 and 6 pts with CCS functional class 3), angiographically confirmed CAD (10 pts with 3 - vessels disease, 16 pts with 2 - vessels disease , and 14 pts with previous myocardial infarction) and mildly depressed systolic function (mean LVEF 52 %) were underwent rest\stress 99mTc-MIBI gated SPECT before and after 10 days administration of diltiazem (mean dose 263 +19 mg\day) (18 pts) or placebo (8 pts). Diltiazem dose was titrated to reach decrease in heart rate at least by 20% from the baseline. The results were processed using Cequal, Siemens Quantification and GS Quantification program. RESULTS: After 10 days diltiazem treatment course the heart rate decreased from 78 + 3 to 63 + 2 bpm (p=.01),wherease in placebo group there were not significant changes. MP improvement was shown in all patients treated with diltiazem. 10 days treatment course with diltiazem compared with placebo was assosiated with significant decrease in the extent & severity perfusion defect, ischemic score and number of ischemic segments. LVEF increased in diltiazem group (ns). Diltiazem Placebo Extent of defect, % 22+4 to 14+3 * 21+7 to21+8 (ns) Severity of defect ,% 395+88 to 233+62* 429+199 to 440+ 193 (ns) Ischemic score, % 25 + 2 to 17 + 2* 24+ 2 to 23+2 (NS) N of ischemic 9+1 to 5+1* 8+2 to 7+2 (NS) LVEF, ml 52+1 to 55 + 5 (ns) 49+1 to 48+2 (ns) LVEDV, ml 123+6,9 to 126+7,6 (ns) 125+5 to 127+4 (ns) LVESV ,ml 59+4,3 to 69+10 (ns) 64+3 to67+5 (ns) * p less .01 Conclusion: Diltiazem- induced heart rate decrease is associated with the myocardial perfusion and contractility improvement in patients with chronic CAD.

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Poster Presentation

Evaluation of Left Ventricular Function Following Coronary Artery Bypass Graft by Technetium-99m Sestamibi ECG-gated SPECT: Comparison with Magnetic resonance Imaging

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Additional Value of Regional Wall Motion and Thickening in Detection of Myocardial Viability.

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G.C. Cantinho (1,2), H.P. Pena (1,2), J.M. Monteiro (1), D.C. Cerqueira (1), P.G. Gonçalves (1), F.G. Godinho (1,2). (1) Atomedical, Lab Medicina Nuclear, Lisboa, Portugal, (2) Instituto de Medicina Nuclear - Faculdade de Medicina de Lisboa, Lisboa, Portugal. Regional wall motion and thickening in perfusion gated SPECT with 99mTc-Tetrofosmin are indirect parameters of myocardial viability. Aim: Our purpose was to determine the value of LVregional wall thickening and regional wall motion for detection of myocardial viability, based on perfusion and function quantification of LV perfusion gated SPECT. Materials and Methods: We studied 21 patients (pts) with past AMI of the anterior wall. Mean age: 66.8±10 y. We also studied a normal control population of 50 patients (mean age 65±2 y). All patients underwent rest SPECT and dipyridamole stress gated SPECT with a total dose of 40 mCi 99mTc-Tetrofosmin. All the studies were performed in an Adac Vertex gamacamera, 64X64 matrix, 30s/view and 64 views. Images analysis was based on qualitative and quantitative calculations, based on Germano’s algorithm (QPS and QGS). 20 segments of the LV were considered. Statistical analysis was done by paired Student T test, for each segment, comparing lesion’s severity, reversibility (Rev), regional wall motion (RWM) and regional wall thickening (RWT). We also considered three regions for analysis: apex (A-2segments), meso-apical segments (MA–14 segments) and basal segments (B-segments). Results: According to the visual analysis, complemented with quantitative analysis, pts were divided in three groups(G): 1. Normals (50 pts); 2. AMI without reversible lesions (10 pts) and 3. AMI with reversible lesions. G EF

EDV

RWM A B

1 66.4±7.3 77±23.8 2 34.3±13.5 199.8±158 0.7±1.6 3 44.6±9.1 131.1±34.5 6.4±1.5

8.1±1.7 6±1.9 8.7±1.4

MA

RWT A

B

MA

Rev A

B

MA

10.9±6.5 25.4±9.6 55.8±11.5 30±83.2 10±33.7 2.4±1.8 9.2±8.1 16.4±7.3 17.5±10.2 74.2±71.2 11.6±22.3 91.3±106.6 8.6±1.8 16.8±9.8 18.9±6.4 22.8±10.4 491.3±267.1 36.1±67 326.4±274

These results show that there are statistical differences between control and CAD pts, as well as between group 2 and 3. Reversibility is also statistically different in all groups (p<0.05). Conclusions: Gated SPECT is of great value because the severity of CAD is based on the perfusion and consequent degree of LV dysfunction. We obtained a RWT <15% for necrotic segments and >15% for viability. RWM was always <3 mm in necrotic segments and higher in the ischaemic ones. The differences found in RWM and RWT allow us to conclude that these parameters are of great importance to characterize peri-necrotic viability.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition MYOCARDIAL PERFUSION / VIABILITY SPECT

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Correlation between Tl-201 myocardial perfusion SPECT and exercise-induced ST segment elevation for detecting viable myocardium in patients with acute myocardial infarction N. Zeidán (1), C. Roiz (1), M.L. Domínguez (1), J.P. Suárez (1), L. Bernardo (1), B. Llana (1), R. Núñez (2), J.L. Negrete (3), A. Alvarez (1). (1) Department of Nuclear Medicine of the Hospital Central de Asturias, Oviedo, Spain, (2) Division of Nuclear Medicine of the Long Island Jewish Medical Center, New York, USA, (3) Department of Cardiology of the Hospital Central de Asturias, Oviedo, Spain. OBJECTIVES: To investigate the correlation between Tl201 myocardial perfusion SPECT and exercise-induced ST segment elevation on ECG for the assessment of myocardial viability in patients with acute myocardial infarction (AMI). MATERIAL AND METHODS: 51 patients (46 males and 5 females) were included in the study 1-4 weeks after anterior wall acute myocardial infarction (AMI). 10 of them also presented inferior wall AMI. The patients were exercise on a bicycle ergometer using a computed system to assess: A) differences in ST segment elevation between stress and rest conditions. B) exercise-induced ST segment elevation higher than 0.5 mm. C) QS complex and inverted T wave on ECG in resting conditions with exercise-induced ST segment elevation higher than 2 mm with positive T wave. All patients were administered i.v. 130 MBq of Tl201 30-60 seconds before ending the exercise, to perform a stress/redistribution SPECT imaging protocol, follow by reinjection with 37 MBq of Tl201 in rest conditions and SPECT after pretreatment with nitroglycerin. SPECT images were acquired using an Elscint SP4 tomogammacamera (Haifa, Israel). Bull-eye quantification, was used to assess the extend of necrotic and isquemic myocardium as a percentage of the total left ventricle and of each of the coronary artery territories; including the assessment of the uptake ratio considered as pathologic. RESULTS: No significant statistic correlation was found between Tl-201 SPECT and ECG exercise test in assessing A and B. In assessing C a significant statistic correlation (p<0.05) was found, with a sensitivity, specificity and positive predictive value of 45%, 100% and 100%, respectively. CONCLUSIONS: There is a significant statistical correlation between Tl-201 myocardial perfusion SPECT findings and exercise-induced ST segment elevation higher than 2 mm and positive T waves, as myocardial viability markers, with a very high specificity. However, the exercise test can not replace SPECT imaging due to its low sensitivity.

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Viability detection in recent myocardial infarction (MI) using Tc99mtetrofosmin (TF) at rest. Role of post injection imaging time interval. T. Athanasoulis, D. Hatzifotiadis, I. Koutsikos, S. Tsiouris, K. Mainta, M. Stathaki, CH. Zerva. Department of Nuclear Medicine of the ‘Alexandra’ University Hospital of Athens, Greece. Aim. The objective was to evaluate the influence of the post injection imaging time interval using TF at rest on viability detection in thrombolyzed patients (pts) with recent MI. Materials and methods. We studied 18 thrombolyzed acute MI pts with high patency grade of the infarct related coronary artery 6 to 8 days post MI. All pts were injected with 555 MBq TF at rest and early and late spect images were obtained 40 min and 3 hours post injection. One month post MI a follow up study was performed in six pts. Three of them had had anterior MI, one lateral, one inferior basal and one inferior MI. In order to compare early and late images the left ventricle was divided into 20 segments and relative uptake in each segment was characterized, according to the maximal activity found in each study as follows: normal: 70-100% of max, mildly decreased: 50-70%, moderately decreased: 30-50% and severely decreased: 0-30%. Results. Comparison of early and late images of the initial study revealed a significant reverse redistribution phenomenon (RRP) in 10/18 pts and specifically involved 6/235 normal, 18/32 mildly, and 15/35 moderately underperfused segments. All 229 normal remote segments and 58 segments with severe perfusion defects remained unchanged. Early images of the initial and follow up study were identical in 5/6 pts while in 1/6 patient (lateral MI) the early image in the follow up study was significantly improved. Late images in follow up studies were considerably improved in 5/6 pts and slightly in 1/6 (inferior MI). Totally in these followed up pts RRP decreased or disappeared in 14/24 segments. Conclusion. These results indicate that TF RRP is very common in thrombolyzed pts with recent MI and spontaneously decreased over one month of follow up. Since TF relative uptake in the early image remains unchanged or even improved over this period of time, early TF image should be the basis for viability detection. Significant post injection imaging delay in this clinical setting may considerably underestimate viability.

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Nitrate 99mTc-Tetrofosmin G-SPECT for the assessment of myocardial viability in patients with severe left ventricular dysfunction: comparison with 99mTc-Tetrofosmin scintigraphy/18FDG-PET imaging A. Giorgetti, GM. Sambuceti, P. Pisani, P. A. Salvadori, S. Di Quirico, P. Marzullo. Institute of Clinical Physiology, CNR-CREAS, Pisa, Italy. Aim: PET flow/metabolic mismatch is considered the nuclear medicine gold standard for the assessment of myocardial viability. Whether baseline/nitrate 99mTc-Tetrofosmin SPECT may represent a sort of “scintigraphic mismatch” similar to that provided by PET is unknown. Materials and Methods: We studied 16 patients (mean age 64±9 yrs, 11 male) with previous myocardial infarction (12 anterior, 4 inferior) and post-ischemic heart failure (G-SPECT EF= 28±7 %). All patients underwent resting and post i.v. nitrate administration (isosorbide dinitrate 0.2 mg/ml, 10cc/h) G-SPECT using 99mTc-Tetrofosmin and a 18-FDG PET scan. Regional wall motion analysis was performed using quantitative G-SPECT (QGS, E.Soft, Siemens) using a 5 point scale (0=normal to 5=diskynesis). Myocardial dysfunction was defined as a regional QGS score W 2. Regional perfusion was assessed by quantitative perfusion score (QPS, E.Soft, Siemens) providing % regional uptake of 99mTc-Tetrofosmin in a 20 segment model. Semiquantitative analysis of FDG uptake was performed using polar maps generated by Siemens ECAT HR + software. In areas with perfusion < 80%, PET viability was identified by a normalized 18-FDG % uptake/baseline 99mTc-Tetrofosmin % uptake >1.2. Results: Three hundred and twenty segments were analyzed. Two hundred and two (63%) resulted dysfunctional at QGS analysis. Of these, 121 resulted viable at PET imaging, while 81 were necrotic. Regional 99mTc-Tetrofosmin uptake resulted higher in PET viable than in necrotic segments both at rest (61±24 vs 44±15%, p<.01) and following nitrates (68±21 vs 44±18%, p<.01). In order to identify myocardial viability, we applied different cut-off (mean % uptake in normal segments -2, -1.5, -1 SD) to rest perfusion data, resulting in a low diagnostic accuracy (63%, 65% and 64%, respectively). The same analysis applied to nitrate GSPECT provided only a moderate increase in accuracy (72%, 73% and 71%, respectively) mainly due to an increased specificity. Applying to G-SPECT studies the same algorithm used for PET (normalized nitrate % uptake/ baseline % uptake), the highest agreement with flow/metabolic mismatch was obtained (accuracy: 92%; sensitivity: 88%; specificity: 95%). Conclusion: In patients with severe left ventricular dysfunction, flow data alone do not permit an accurate estimation of myocardial viability. In dysfunctioning segments, the comparison of resting and post-nitrates G-SPECT provided similar results to those obtained by means of PET flow/metabolic mismatch.

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n MYOCARDIAL PERFUSION / VIABILITY SPECT Acute oral trimetazidine administration to enhance the detection of myocardial viability by gated Tc-99m tetrofosmin SPECT: a comparison with nitrate-gated Tc-99m tetrofosmin SPECT A. Tutus (1), M. Kula (1), O. Turhal (1), A. Abaci (2), M. Basbug (1), R. Topsakal (2), A. Oguzhan (2). (1) Erciyes University, School of Medicine, Department of Nuclear Medicine, (2) Erciyes University, School of Medicine, Department of Cardiology, Kayseri, TURKEY. Aim: Trimetazidine (TMZ) is an antiischemic drug protecting the myocardium from ischemic damage through the preservation of mitochondrial oxidative metabolism, without any hemodynamic effect. A comparison was performed between gated Tc-99m tetrofosmin (TF) SPECT at baseline and after acute oral TMZ administration, and nitrate-gated TF SPECT studies in order to assess whether TMZ enhance the detection of viable myocardium with TF. Material and methods: Thirty patients with previous myocardial infarction and a left ventricular ejection fraction < 40% underwent baseline, post-nitrate (nitrate infusion) and postTMZ (60 mg orally) gated TF studies. The left ventricle was divided into 19 segments, which were analyzed for perfusion and wall motion on a 4 and 3-point severity scale, respectively. A segment was predetermined to be viable by perfusion imaging if the segment score W 55% of normal and/ or by preserved myocardial wall motion. Results: On baseline TF studies 206 of the 570 segments that were analyzed had < 55% of peak activity. Fifty-six (27%) of the 206 segments with severely diminished or absent myocardial perfusion showed hypo kinetic wall motion by gated-SPECT. Twenty percent of these segments showed reversibility after TMZ administration, with an increase in TF uptake from 49.2± 5.6 to 61± 4.2 of peak activity. All reversible segments after TMZ administration had viability criteria on nitrate-gated TF SPECT studies. There was concordance between TMZ and nitrate-gated TF SPECT studies regarding the presence of myocardial viability. Conclusion: Our results suggest that TMZ administration may increase myocardial uptake of TF in infracted but viable myocardial areas is probably related to an improvement in mitochondrial oxidative metabolism that is essential to TF retention.

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Identification of reversible segments in myocardial perfusion studies with Tc-99m MIBI and tetrofosmin:infusion versus bolus O. Yapici, M. Sahin, S. Kolcu, T. Basoglu. Deparment of Nuclear Medicine, Faculty of Medicine, Samsun, Turkey. New protocols of cardiac imaging have been developed as an alternative to traditional rest/stress Tc-99m MIBI or tetrofosmin scintigraphy which are frequently accused to underestimate myocardial viability. The aim of our study was to compare the method of bolus injection versus infusion of Tc-99m MIBI or tetrofosmin in the identification of defect reversibility. Materials and Methods: Twenty-five patients (22 male, 3 female) with documented coronary artery disease were divided into two groups. Rest/stress Tc-99m MIBI and late Tl-201 (1824hr) SPECT images in group 1 (14 patients) and rest/stress Tc-99m tetrofosmin and late Tl201 SPECT images in group 2 (11 patients) were obtained. For late redistribution images, 74 MBq Tl-201 were injected. All patients underwent infusion studies in a separate day. SPECT was performed following two hours infusion of 370 MBq Tc99m MIBI or tetrofosmin in 100cc normal saline solution. Short axis slices were grouped as apical, midventricular and basal, and were divided into 8 segments. Apex was divided into 2 segments in vertical long axis. A total of 26 segments for each patient were semiquantitatively evaluated by using a 10step colour scale. Values less than 80% in myocardial segments were accepted as decreased perfusion. At least 10% increase in relative uptake on the subsequent images was considered reversible. Defects of 10% alterations were accepted as nonreversible if relative activity remained <50% on the subsequent images. The differences of relative activities between rest and infusion images were compared by paired-t test while student-t test was used to compare late Tl-201 images with others. Results: Stress myocardial perfusion images showed defects in 176 of 364(48%) segments of group 1 and 93 of 286 (32%) segments of group 2. In group 1, defect reversibility was detected in 53 of 176 (30%); 63 of 176 (35%) and 60 of 176 (34%) segments in rest, infusion and late Tl-201 images respectively. In group 2, 16/93 segments (17%) in rest; 17/93 segments (18%) in infusion and 23/93 segments (24%) in late Tl-201 images showed reversibility. The degree of defect severity and reversibility in myocardial segments with initial defects were shown in table. Group 1 (n=176) mean±s.d. Group 2 (n=93) mean±s.d. (MIBI) (% of peak ) (Tetrofosmin) (% of peak ) Stress (S) 53,0±16,4 Stress (S2) 57,5±12,5 Rest (R)* 54,8±19,3 Rest (R2)# 58,9±13,7 Infusion (INF) 58,1±18,7 Infusion (INF2) 59,0±12,7 Late Tl-201Redistr. 57,1±17,3 Late Tl-201 Redistr. 60,0±13,8 (LR)** (LR2)## *p=0,000 INF vs R, ** p>0.05 INF vs LR; #,## p>0.05 INF2 vs R2, INF2 vs LR2 Conclusion: The myocardial SPECT of Tc-99m agents acquired following infusion are as good as late Tl-201 images in the evaluation of defect reversibility. Further work is necessary with larger patient population.

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E. Itti (1), Z. Malek (1), J. Rosso (1), J.L. Monin (2), P. Gueret (2), T. Yasuda (3), M. Meignan (1). (1) Department of Nuclear Medicine, H. Mondor Hospital/Paris XII University, Creteil, FR, (2) Department of Cardiology, H. Mondor Hospital/Paris XII University, Creteil, FR, (3) Department of Nuclear Cardiology, Massachusetts General Hospital/Harvard Medical School, Boston, USA.

S. Erhamamci, A. Dirlik, O. Ozyurt, O. Omur, E.T. Acar, I. Karapolat. Ege University Medical Faculty Department of Nuclear Medicine, izmir, Turkey.

3D voxel-based quantification of perfusion defects by template matching in patients with myocardial infarction

Aim: Quantification of perfusion defects due to a myocardial infarction (MI) is usually performed by means of 2D segmental analysis of the bull’s eye, but reduction of 3D data to 2D may pose problems. This study presents and evaluates a 3D voxel-based approach. Materials and Methods: We studied 37 men with a history of MI, who underwent a 1-day viability protocol including stress, redistribution and reinjection 201Tl tomograms. For each one of the 3 acquisitions, myocardial perfusion was analysed using 3 methods of increasing complexity: 1) an expert visual scoring of the bull’s eye, 2) a segmental quantification of the bull’s eye with comparison to a normal population of 20 healthy men, 3) the voxel-based software. Briefly, the latter automatically extracts myocardial edges, matches them to a standard 3D template by elastic deformation and compares the perfusion intensity in each voxel to the intensity of the corresponding voxel in a normal gender-matched population of 50 healthy men. Defects were expressed as hypoperfusion indices, regrouping information of size and severity within a single variable. Results: Using visual scoring (considered the gold standard), hypoperfusion indices at stress reached 27 ± 13% of the entire myocardium. Both 2D and 3D quantitative methods underestimated these indices by a half (15 ± 9% (p < 0.0001) and 12 ± 6% (p < 0.0001), respectively). However, linear regression showed r coefficients > 0.90. At redistribution, visual scoring showed significant partial reversibility of 3 ± 7% (p < 0.01); 2D quantification did not find this reversibility (0 ± 5%), while 3D analysis found it (1 ± 3%, p < 0.01). Partial reversibility was confirmed at reinjection with both 2D and 3D quantitative methods. Finally, hypoperfusion indices of the inferior wall were less underestimated by the 3D method than by 2D quantification. Conclusion: the 3D voxel-based approach appears more sensitive for the detection of viability on redistribution images, compared to segmental 2D bull’s eye which demonstrated reperfusion only at reinjection. Moreover, evaluation of the inferior wall seems more accurate with the 3D method than with the 2D method.

Comparison of Exercise-rest-reinjection Tl-201 imaging and rest sublingual isosorbide dinitrate Tc-99m MIBI imaging for assessment of myocardial viability

Aim: Nitrate administration has been proposed to enhance the detection of myocardial viability when performing myocardial perfusion imaging. In the current study, we aimed to compare Tl-201 exercise-rest-reinjection protocol with rest isosorbide dinitrate (ISDN)-Tc99m MIBI study in the same population examined for the myocardial viability. Methods: Twenty-six patients (23 men, 3 women, mean age 59.77±10.05 years) with coronary artery disease who had fixed segmental defects on exercise-rest-TI-201 imaging were studied. All of them underwent Tl-201 reinjection study. Within 1 week of Tl-201 imaging, rest Tc99m MIBI imaging was performed after sublingual 5mg ISDN administration. Regional tracer uptake was evaluated in 20 myocardial segments for all patients. A total 520 myocardial segments were assessed by semiquantitative analysis. Viability was defined as presence of tracer uptake ≥50% of peak activity on each study. Result: 211 segments of the 520 segments that were analyzed, had <50% of peak activity on Tl-201 rest studies. Twenty percent (42 segments) of these segments showed reversibility after reinjection Tl-201 imaging. 55 segments (27 %) described as viable on the rest ISDNTc99m MIBI imaging. There was 89 % concordance between the rest ISDN-Tc99m MIBI study and Tl-201 reinjection study regarding viable myocardial segments. Of the 23 segments with discordant results, 18 were irreversible on Tl-201 reinjection study, but showed ≥50 % uptake on rest ISDN-Tc99m MIBI. Conclusion: Observation of good agreement between Tl-201 reinjection and rest ISDNTc99m MIBI study studies led us to suggest the use of isosorbide dinitrate enhanced imaging in the evaluation of myocardial viability.

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Poster Presentation

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Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition CARDIOVASCULAR: MISCELLANEOUS

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Fatty acid metabolic imaging with PHIPA 3-10 in non-ischemic myocardium J. Zehelein (1), J. Hoffend (2), M. Licka (1), M. Rosenberg (1), U. Haberkorn (2), H. A. Katus (1), M. Eisenhut (3), R. Zimmermann (4). (1) Innere Medizin III, Universitätsklinik Heidelberg, (2) Abteilung Nuklearmedizin, Universitätsklinik Heidelberg, (3) Abteilung Radiochemie und Radiopharmakologie, DKFZ Heidelberg, (4) Medizinische Klinik I, Klinikum Pforzheim, Germany. F [123I]PHIPA 3-10, 13-(4’-[123I]iodophenyl)-3-(p-phenylene)tridecanoic acid, is a radiolabelled synthetic long chain fatty acid. Studies in rats have shown a prolonged myocardial retention due to metabolic trapping after one b-oxidation cycle caused by the p-phenylene group in the alkyl chain. Aim: The purpose of the present clinical study was to characterise myocardial uptake and retention of PHIPA in the non-ischemic human heart. Therefore, serial imaging with PHIPA was performed in 8 patients with atypical chest pain and normal thallium stress test. Materials and methods: After injection of 150 MBq PHIPA, planar iodine-123 imaging (LAO 30°) using a Siemens Orbiter 7500 gamma camera equipped with a LEAP collimator was carried out dynamically during the first 20 minutes after injection. Additional static planar images were performed after 60 and 240 minutes, respectively. Results: PHIPA myocardial time activity course was biphasic: the uptake reached a maximum approximately 10 minutes after injection and amounted to 1.8% ± 0.4% of the injected dose with a homogeneous myocardial distribution. PHIPA activity then decreased by 28.0% ± 7.4% and reached a „steady state“ one hour after injection (half life >1 h p.i.: 15.7 ± 7.7 h). Liver uptake exceeded the myocardial uptake by the factor of 2 and showed a maximum value 10 minutes after injection. Conclusion: The data demonstrate prolonged retention of PHIPA in the non-ischemic human myocardium and suggest the use of this fatty acid for clinical SPECT investigations in myocardial disorders. ACKNOWLEDGEMENTS: A. León, E. Chiotellis, A. López de Cerain, O. Ezpeleta, S. Onetto, M. González, CHLCC, CSIC, PEDECIBA-Química.

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A compartment model analysis for investigation of the myocardial fatty acid metabolism in patients with ischemic heart disease and hypertrophic cardiomyopathy A. Okizaki (1), N. Shuke (1), C. Zhao (1), J. Sato (1), Y. Ishikawa (1), N. Hasebe (2), K. Kikuchi (2), T. Aburano (1). (1) Department of Radiology Asahikawa Medical College, Asahikwa, Japan, (2) Department of Internal Medicine Asahikawa Medical College, Asahikwa, Japan. A compartment model analysis for investigation of the myocardial fatty acid metabolism in patients with ischemic heart disease and hypertrophic cardiomyopathy. Aim: The purpose of this study was to investigate the myocardial fatty acid metabolism in patients with ischemic heart disease (IHD) and hypertrophic cardiomyopathy (HCM) from dynamic SPECT through a compartment model analysis. Materials and Methods: Eleven patients with ischemic heart disease and 5 patients with hypertrophic cardiomyopathy were studied. Iodine-123 beta-methyl-iodophenyl-pentadecanoic acid (I-123 BMIPP) dynamic SPECT and myocardial perfusion SPECT were performed in them within 2 weeks. After an injection of I-123 BMIPP (111MBq), the dynamic SPECT was performed on a three-headed digital gamma camera system. The myocardial perfusion SPECT was performed with Tc-99m Tetrofosmin (740MBq) on the same system. The left ventricular myocardium was divided into 13 segments in short-axial and vertical long images, and these 208 segments were categorized according to the findings on myocardial perfusion SPECT and clinical information as normal, IHD and HCM. By using the time-activity curves (TACs) of these segments as response tissue functions and the TACs of Aorta as input functions, we analyzed I-123 BMIPP pharmacokinetics through a 2-compartment model with SAAM program. We defined k1 as influx rate constant, k2 as outflux rate constant and k3 as specific uptake rate constant. And we calculated k1/k2, k3 and clearance (k1k2/(k2+k3)). Results: The results were summarized in the table. Statistically significant differences were seen in k1/k2, k3 and clearance between normal and IHD. The parameters, k1/k2 and k3 showed statistically significant differences between normal and HCM, but clearance did not. The average and standard deviation of each rate constants Normal Ischemia HCM K1/K2 0.620±0.158 0.539±0.209* 0.421±0.184*** K3 0.00325±0.00130 0.00249±0.00179** 0.00584±0.00417*** Clearance (K1K3/(K2+K3)) 0.00183±0.00061 0.00109±0.00046*** 0.00184±0.00073 *p<0.05 **p<0.01***p<0.001 Conclusion: A compartment model analysis could be useful to clarify the myocardial fatty acid metabolism in patients with IHD and HCM.

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Various Imaging Modalities after Acute Myocardial Infarction. Comparison of Scintigraphic, Echocardiographic, Magnetic Resonance Viability Methods I. Balogh (1), B. Fornet (2), I. Palasti (3), R. Mizik (3), É. Toth-Fekete (2), A. Medveczky (1), E. Marosi (4), F. Szaboky (3). (1) Uzsoki street Teaching Hospital, Department of Nuclear Medicine, (2) International Medical Center, (3) Railway Hospital, (4) National Medical Center, Department of Cardiology and Internal Medicin, Budapest, Hungary. Aim: To distinguish the scar and viable myocardium has great importance before revascularisation procedure in the pts with severe global or regional left ventricle dysfunction after acute myocardial infarction (AMI). Comparing the results of the low dose dobutamine echocardiography (DE), the rest- redistribution SPECT Tl-scintigraphy (TlSC), the gated-SPECT Tc-tetrofosmin-scintigraphy (TcSC) with the administration of nitrate and MRI using Gadolinium DTPA (GdMR) after AMI, we tried to determine the diagnostic value of these methods. Methods: We examined (up to the present) 14 pts between 9-14 days after AMI and in every examination 16 segments (sgm) of left ventricle were analysed. The first examination was DE, and within 72 hours TlSc, gated SPECT, nitrate administered TcSC and GdMR were performed. The criteria of viable sgm were: 1) on DE using 4 graded scale system >= 1 grade wall motion improvement, 2) on TlSC <= 50% decreased perfusion and/or reversibility of the perfusion abnormalities, 3) on the gated SPECT, nitrate aministered TcSC <= 50% decreased perfusion of the akinetic sgm, 4) on GdMR akinetic sgm without delayed contrast enhancement (after 15 minutes). Results: Out of all analysed 224 sgm, 63 sgm showed decreased motion on DE, and the ratio of viable and non viable sgm was 47/16. This ratio was on TlSC 49/14, on TcSC 41/22, on GdMR 45/18. Comparing the TlSC, the gated SPECT, nitrate administered TcSC and GdMR results to DE sensitivity for the detection of viability were with TlSC 89.3%, TcSC 78.7%, GdMR 84.9% and specificity were of TlSC 56.2%, TsSC 65%, GdMR 90%. Conclusion: The gold standard for identifying the viable myocardium is the good result of the revascularisation, and consequently the recovery of the function. Our examinations were performed before operation, for this reason we could not make a comparison with postoperative effectiveness. But on the basis of the high sensitivity of all these 4 methods, in addition to generally used DE and TlSC, the newer method with gated SPECT, nitrate administered TcSC and the brand new GdMR can be considered to be appropriate imaging modalities for detecting myocardial viability as well.

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Long term diabetes melitus type II can cause the disturbances in the circulation of the lower limbs - the results in the group of ten years of disease, by using the lower limbs perfusion scintygraphy by means of MIBI. B. Malkowski (1), B. Rogulski (2), Z. Maziarz (1), W. Tryniszewski (1), M. Kozlowska (1). (1) Department of Nuclear Medicine of the Military Medical University Lodz Poland, (2) II Departement Of Internal Medicine of the Military Medical University Lodz Poland. Lack of clinical signs of deterioration in the lower limbs’ circulation does not mean that diabetes does not damage the microcirculation. Knowledge about this process can change the treatment and bring better results in long term management of the patients. Aim: The aim of our study was: 1. To assess the lower limbs’ perfusion in the group of patients with diabetes mellitus type II with no clinical signs of disturbances in lower limbs’ circulation. 2. Compare the results with other non-invasive diagnostics to assess the value of the method. 3. Compare perfusion results with normal results according our own database. Materials and Methods: 35 male patients without clinical signs of the lower limbs’ circulatory disease were entered into the study. Medium age was 64,4± 5,2 years. Lower limbs’ perfusion scintygraphy was performed in rest, 5 min. after the injection of 11,1MBq/kg 99mTc MIBI. The whole body and every part of the lower limbs’ (tights, calves) acquisition were performed on ELSCINT SP6HR gamma-camera. Symmetry of the tights and calves’ perfusion (ST, SC.), indexes of tight (IRTP, ILTP) and calves’ (IRCP,ILCP) perfusion for each side of the lower limbs were estimated. USG-Doppler, arm–ancle’s index, blood pressure and laboratory tests were performed on every patient to exclude circulatory disturbances. Normal results: ST–102,76%±7,6 SC- 99,27%±9,8 IRTP–10,17±2,5 ILTP–9,9±2 IRCP–10,4±2,3 ILCP–10,46±2,5. Pathological results were above these values. Results: We found abnormalities in the perfusion studies ST–92,16%±4,6 SC- 86,27%±7,6 IRTP–12,17±2,5 ILTP–13,4±2 IRCP–14,4±3,7 ILCP–15,48±3,6, glucose , cholesterol, and triglyceride concentration. In this group additional examination (USG-Doppler, arm–ankle’s index )did not show any circulatory disturbances. Conclusion: 1.The lower limbs’ perfusion scintygraphy indexes in patients with long term diabetes mellitus without circulatory disturbances show statistical differences from estimated normal values.2.Determination of these values enables full diagnosis and proper treatment in patients with the pathology of the lower limbs’ circulation.

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n CARDIOVASCULAR: MISCELLANEOUS P_109

Biodistribution of (123)I-(rh)VEGF-165 in vivo: Possible Implications for Myocard Angiogenesis Therapy and Tumor Imaging S. Li (1), M. Peck-Radosavljevic (2), C. Poetzi (1), T. Traub-Weidinger (1), J. Preitfellner (1), S. Hanisch (1), O. Kienast (1), P. Angelberger (3), R. Dudczak (1,4). (1) Department of Nuclear Medicine, University of Vienna, (2) Department of Internal Medicine IV, Division of Gastroenterology and Hepatology, University of Vienna, (3) Austrian Research Center, Seibersdorf, Austria, (4) Ludwig Boltzmann Institute of Nuclear Medicine, Austria. Aim: Recently, the use of recombinant human vascular endothelial growth factor (rhVEGF) to enhance myocardial collateral blood vessel function may represent a new approach to the treatment of cardiovascular diseases, such as restenosis after angioplasty, vascular bypass graft occlusion, and transplant coronary vasculopathy, for which no known effective therapy exists. However, up to date, the pharmacokinetic studies and biodistribution are lacking for rhVEGF. In this study, the biodistribution and resulting dosimetric calculation for the tracer exposure of different organs and tumor masses were investigated in patients with pancreatic adenocarcinoma based on 123I-(rh)VEGF165. Material and Methods: Seven patients with pancreatic adenocarcinomas were investigated. Dynamic und whole body studies with 123I-(rh)VEGF165 were performed up to 24 h after injection. Blood and urinary activity were measured simultaneously. Based on the regional tissue uptake kinetics, residence times were calculated and tracer exposure of different organs were estimated. Results: The radiolabeling of (rh)VEGF165 with iodine-123 was performed without loss of its receptor specificity and biological activity. No adverse reaction was noted in any subject after intravenous administration of 123I-(rh)VEGF165. The tumor uptake of 123I-(rh)VEGF165 in the patients with pancreatic adenocarcinomas was rapid and modest. Estimated radiation absorbed doses were high in the lungs, kidneys, spleen, liver and heart. Residence times based on 123I-VEGF165 were 0.52-1.47 h in lungs; 0.28-0.46 h in kidneys; 0.09-0.30 h in spleen; 0.43-0.80 h in liver and 0.13-0.27 h in heart. Within 24 hours, approximately 80% of the injected dose cleared through the kidneys. Conclusion: The results may have important implications for myocardial angiogenesis therapy and tumor imaging using VEGF. Furthermore, these data encourage further studies of physiological and pathophysiological role of VEGF.

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Exertional dyspnea and walking duration are unrelated to the changes in pulmonary and hepatic blood volumes in patients with mitral stenosis or chronic heart failure during walking G. Marotta (1), G. Baccelli (2), F. Voltini (1), M. Catalano (2), A. Finzi (3), L. Preti (3), V. Salvatore (1), P. Gerundini (1). (1) Department of Nuclear Medicine, Ospedale Maggiore di Milano IRCCS, (2) Centro di Fisiologia Clinica ed Ipertensione and Istituto di Clinica Medica e Terapia Medica, Università di Milano, (3) Cardiology Department, Ospedale Maggiore di Milano IRCCS, Milan, Italy. Background: The mechanisms responsible for exertional dyspnea and walking performance are not well understood in patients with heart disease. Methods: We studied 16 patients with mitral stenosis and 24 with chronic heart failure who had dyspnea during walking, but not at rest and on lying down. The blood volume shifts occurring in the liver and three fields of the right lung were measured simultaneously and continuously by a scintigraphic method during treadmill walking and lying down from standing. The severity of exertional dyspnea and walking duration were also noted. Walking and the postural change were performed twice. The study allowed to investigate the relationship among blood volume changes, and exertional dyspnea and walking duration both among patients and within patients. Results: In patients, no relationship among the variables studied was found. In the same patient: 1) a reduced exertional dyspnea or an increased walking duration during the second test were not associated with different changes in blood volume shifts; and 2) walking induced dyspnea, and blood volume shifts in the liver and in the right lung upper and middle fields that were similar to, and in the right lung lower field that were smaller than those due to the postural change, although the latter was not associated with dyspnea. Conclusions: These results accord to indicate that exertional dyspnea and walking duration are not influenced by the walking-induced pulmonary and hepatic blood volume shifts in the patients with mitral stenosis and with chronic heart failure.

* This study was partly supported by the Pfeiffer Scholarship of Austrian Society of Nuclear Medicine and Anniversary Foundation of Austrian National Bank, Project No. 8320.

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P_112

A.I. Armeniakos (1), F.K. Panou (2), G.B. Dounis (1), K.S. Theocharis (1), I.A. Lakoumentas (1), B.K. Kotseroglou (2), E. Veve (1), TH. Stratigou (1), A.I. Karavidas (2). (1) Department of Nuclear Medicine, Athens, Germany.

M.Z. Zigman (1), A.B. Balenovic (1), I.B. Bonic (2), B.C. Car (2). (1) Department of oncology and nuclear medicine, (2) Department of internal medicine, Zagreb, Croatia.

From previous studies it has been shown that plasma brain natriuretic peptide (BNP) levels were correlated with the clinical severity of Hypertrophic Cardiomyopathy (HCM), as graded according to the NYHA classification. Aim of this study was to investigate the possible relation of BNP levels with clinical and echocardiographic (ECHO) parameters in patients (pts) with HCM. Methods: In 15 pts with HCM (mean age 55.9±15 years) plasma levels were measured by an immunoradiometric assay (SHIONORIA BNP by CIS-Diagnostics). A cut-off point of 18.4 pg/ml was considered as the upper limit of normal values. A complete clinical and ECHO examination was performed in every patient. The following variables of left ventricular (LV) systolic and diastolic function were determined: ejection fraction (EF), isovolumic contraction time (IVCT), ejection time, peak velocities of E and A waves, their ratio E/A, deceleration time of the E wave (DT) and isovolumic relaxation time (IVRT). Statistical analysis of our data was performed by non-parametric Mann-Whitney test and correlations were performed by using Pearson`s correlation coefficient. Results: 10 pts had abnormal BNP plasma levels (162.9±190 pg/ml) (group A) and 5 pts had normal BNP plasma values (12.1±4 pg/ml) (group B). No significant difference was noticed between the two groups with regard to age, sex, body surface area, heart rate, systolic and diastolic blood pressure. The following differences in ECHO parameters were found: a) Awave: group A 0.75±0.19 m/sec, group B 0.55±0,13 m/sec (p=0.032), b) IVRT: group A 124±10 msec, group B 104±9 msec (p=0.008), c) LV diastolic dimension: group A 43±0.3 mm, group B 48.04 mm (p=0.036). No significant difference was observed for the other measured ECHO parameters. Plasma BNP levels were positively correlated with NYHA class (r=0.545, p=0.035). Conclusions: Assessment of BNP plasma levels seem to be important in pts with HCM since it was found to be: a) positively related to clinical severity and degree of LV diastolic dysfunction b) inversely related to LV diastolic dimension.

Angioscintigraphic analysis of regional circulation disturbances in chronic leg ischemia

The purpose of this investigation was to determinate possibility of non-invasive quantification of regional functional vascular reserve with radiofarmaceuticals in basal conditions and after test of reactive hyperaemia in patients having obliterary artery disease of lower extremities. Study included healthy persons (group A, N=16) and 60 symptomatic patients who underwent complete clinical and diagnostic investigations and were classified according to their diagnosis into three groups: atherosclerosis of lower extremities (group B, N=32), diabetic angiopathy (group C, N=18), thromboangiitis obliterans (group D, N=10). Dynamic and blood pool scintigraphy were performed after in vivo labeled erythrocytes with 99mTc-pirofosfat in basal conditions and after test of reactive hyperemia with blood pressure cuff for each patient. Three scintigraphic parameters were derived from computer analyses in three regions of interest (calf, feet and toes) in each leg. Groups were analyzed according to the following parameters: 1) basal accumulation index (BAI) which presents normalized basal regional count numbers, 2) index of reactive hyperemia (IRH) presents change in regional count numbers during test of reactive hyperemia and 3) retention index (RI) presents normalized delayed regional count numbers. BAI IRH Calf Feet Toes Calf Feet Toes A* 1,2±0,19 0,9±0,15 0,7±0,15 3,8±0,25 2,5±0,20 1,7±0,20 B** 0,6±0,22 0,3±0,15 0,1±0,08 1,5±0,50 1,3±0,20 1,1±0,15 C** 0,4±0,20 0,2±0,10 0,1±0,10 1,3±0,25 1,2±0,10 1,0±0,10 D** 0,7±0,25 0,2±0,15 0,1±0,15 2,5±0,30 1,1±0,20 1,0±0,10 *p<0,01 A vs. (B, C, D) **p<0,01 B vs. C, C vs. D, B vs. D

Calf 1,1±0,20 1,2±0,18 1,3±0,20 1,3±0,30

Feet 1,1±0,20 1,2±0,15 1,4±0,25 1,7±0,25

RI Toes 1,1±0,30 1,2±0,10 1,4±0,25 1,4±0,30

Quantitative parameters gained from computer analysis of scintigraphic data enables noninvasive studying of regional circulation in basal conditions and preserved functional vascular reserve in patients having obliterating diseases caused by different etiology.

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Poster Presentation

Value of brain natriuretic peptide in assessment of patients with Hypertrophic Cardiomyopathy

Poster_2002.qx

24.07.2002

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n CARDIOVASCULAR: MISCELLANEOUS P_113

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A. Wragg (1), N.W. Garvie (2). (1) Department of Cardiology, London Chest Hospital., (2) Department of Nuclear Medicine, Royal London Hospital, London, UK.

P. Oturai (1), T. Lorenzen (2), J. Nørregaard (2), L. Rørdam (1). (1) Dept. of Clin. Physiol./ Nuclear Med., Bispebjerg Hospital, University of Copenhagen, (2) Dept. of Sports Medicine, Bispebjerg Hospital, University of Copenhagen.

The exercise treadmill test , although still widely used in the U.K as a screening procedure for myocardial ischemia , has often been shown to be unreliable. ST depression is frequently seen in normal individuals, particularly females,. The Adenosine stress protocol, which does not elicit an inotropic response, can, however, also induce ST depression. Here, the mechanism may be due to “coronary steal”, (regional myocardial ischemia developing in the territory of a stenosed artery , due to blood flow diversion caused by vasodilation of adjacent “healthy” arteries). The phenomenon may therefore be potentially more predictive of coronary artery disease. METHODOLOGY: To investigate this hypothesis, 2 groups of patients with angina – type chest pain were studied , using a 2 day MIBI protocol. The first group (60 patients,48 males ) were stressed by treadmill exercise (ETT), and the second group (61 patients,31 males ) underwent a standard Adenosine protocol. 12-lead continuous ECG monitoring was performed, and recorded at 3 minute (ETT) and 1 minute (Adenosine) intervals, respectively . Significant ST depression was documented , for comparison against scintigraphic outcome. RESULTS: 13 (22%) patients in each group showed ST depression. Of those with no stressinduced ST depression , 6 (13%) showed ischemia after ETT, and 8 (17%) after Adenosine. When ST depression occurred with ETT, 6 (46%) subsequently had scintigraphic evidence of ischemia, and 5(39%) with Adenosine. When ST depression developed with no later evidence of ischemia, 2/2 females (100%) compared to 5/11 males (45%) showed this feature with ETT, and 5/6 (83%) females and 3/7 males (43%) after Adenosine. CONCLUSIONS:: Overall, in both groups, ischemia was proportionately more common in patients with stress-induced ST depression, in the ratio of approximately 3:1. However , significant numbers of patients with ischemia failed to show ST depression ( 14/25 or 56%) “False-positive” ST depression was more commonly seen in normal females in both groups , with a female:male ratio of approximately 2:1. ST depression developing as part of an Adenosine stress protocol is no more predictive of ischemia , than with treadmill exercise.

Aim: Invasive pressure measurements are currently the method of choice for diagnosing chronic compartment syndrome (CCS). SPECT with radioactive tracers used for detecting myocardial ischaemia have been suggested as an alternative diagnostic tool. We aimed to evaluate whether increased muscle compartment pressure was associated with signs of decreased muscle perfusion detected by 99mTc-tetrofosmin SPECT. Material and methods: Preliminary data including the first 14 patients with exercise-related pain in muscle groups of the lower leg and clinical suspicion of CSS are presented. Ten males and 4 females, mean age 31y (range 19-57) have been included. Five patients had symptoms in the deep posterior, 4 in the superficial posterior, and 5 in the anterior muscle group of the lower leg. All patients had exercise-related pain in both legs. Compartment pressure was measured invasively in the relevant muscle groups. Measurements were performed before and after treadmill exercise inducing the well known leg pain. Furthermore, SPECT of the lower leg was done twice 30 min after the injections of 300 MBq 99mTc-tetrofosmin. Resting SPECT was performed before the compartment pressure measurement and exercise SPECT was performed one week later with tracer injection 2 min before termination of exercise, inducing leg pain comparable to what was obtained on the day of pressure measurements. Results: Compartment pressures of >30 mmHg and/or >20 mmHg and/or >resting pressure measured 1, 5 and 15 min after termination of exercise were considered pathologically increased. Increased pressures were registered in 6 patients (43%). In 4 patients in the anterior muscle group, in 1 patient in the deep posterior muscle group, and in 1 patient in the superficial posterior muscle group. Transversal reconstructed SPECT images of the lower legs were evaluated semi-quantitatively and exercise induced changes in muscle tracer activity were registered. In 3 of the patients with increased pressure (2 in the anterior and 1 in the deep posterior muscle group) there was decreased muscle tracer activity in the relevant muscle compartments during stress compared with rest. However, in the other 3 patients no association was found between exercise-induced increase in muscle pressure and changes in muscle tracer activity. Conclusion: Tc-99m-tetrofosmin SPECT seems not to be an alternative method for detecting chronic exertional compartment syndrome of the leg since 50% of the patients with pathologically increased compartment pressures had normal perfusion SPECT.

Does ST depression during Adenosine Infusion imply coronary steal?

P_114

Can Pulmonary Uptake of Tc99m-MIBI Be a Marker of Coronary Artery Disease or Left Ventricular Dysfunction? U. Yararbas, O. Ozyurt, A. M. Argon, K. Kumanlioglu. Department of Nuclear Medicine of Ege University Hospital, Izmir, Turkey. Aim: When interpreting myocardial perfusion scans, increased pulmonary uptake of Tl-201 on post-stress images is used as a marker of severe coronary artery disease and left ventricular decompensation. Tc99m-MIBI is also routinely used for myocardial perfusion scintigraphy but there is no consensus on the clinical significance of pulmonary uptake of this radiotracer. The aim of our ongoing study is to show whether pulmonary uptake of Tc99m-MIBI can give information on left ventricular function and to see the effect of imaging timing on lung uptake. Material-Method: A total of 54 patients (34 male and 20 female) were included in the study. Age range was 23-76. Patients were divided into 3 groups: Group A: Patients with normal perfusion scans and no left ventricular dysfunction (40 patients) Group B: Patients with low ejection fraction and global hypokinesia according to echocardiography (5 patients) Group C: Patients with ischemia or infarction on perfusion scan but normal ejection fraction value on echocardiography (9 patients) All patients underwent 2-day exercise Tc99m-MIBI myocardial perfusion scan using modified Bruce protocol. Both early (5th min) and delayed (45th min) images were obtained after stress and rest injections. Lung/heart (L/H) ratios were calculated using tomographic images. ROIs including the whole myocardial activity and a portion of left lung at the vicinity of myocardium were drawn; maximum counts within the ROIs were used for the L/H ratio calculation. Results: L/H ratios were as follows: Group A Group B Group C Poststress 5th min 0,39±0,04 0,49±0,1 0,4±0,07 th Poststress 45 min 0,34±0,04 0,44±0,09 0,35±0,03 After rest inj 5th min 0,43±0,04 0,51±0,1 0,42±0,05 th After rest inj 45 min 0,38±0,04 0,45±0,08 0,37±0,04. According to non-parametric statistical tests, significant difference was observed only between group A and B on post-stress 45th min images. Conclusion: Preliminary results of our study revealed that during stress or rest acquisitions, L/H ratios calculated over 5th min stress and 5th and 45th min rest images are not informative on left ventricular function. In patients with ischemic or infracted myocardium if left ventricular ejection fraction is preserved, increased L/H ratios are not expected. Although statistically significant difference was found at post-stress 45th min images between group A and B, since group B includes only 5 and group C; 9 patients, further validation of the results are needed by increasing number of cases.

S218

99mTc-tetrofosmin SPECT for detecting chronic exertional compartment syndrome of the leg

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition MYOCARDIAL PERFUSION SPECT - METHODOLOGY, QUALITY CONTROL

P_116

Minimal count level required for quantification of left ventricular function with gated myocardial perfusion tomography C. Vanhove, K. Muylle, P.R. Franken. Department of Nuclear Medicine of the Free University Brussels, Belgium. Aim: The aim of this study was to determine the minimal count density required for accurate quantification of global and regional function using gated myocardial perfusion tomography and the QGS algorithm. Material and Methods: Ten patients with low likelihood of coronary artery disease were injected with 925MBq of Tc99m labelled tetrofosmin. Imaging was started 60min after tracer administration on a 3-head gamma camera equipped with LEHR collimators. Parameters of acquisition were as follows: 360-degree rotation, 96 projections, 64x64 matrix, 5.79mm pixel size, step-and-shoot, 40s per step and 8 time bins. In order to create test data sets with lower count densities, the original data were redistributed using binomial deviates. For each patient, five different noise realizations were generated for six different noise levels corresponding to 1/2, 1/4, 1/6, 1/8, 1/10 and 1/16 of the original count density. Transverse slices were reconstructed using filtered backprojection (Butterworth filter: cut-off frequency 0.44 cycle/cm, order 5) and reoriented according to the left ventricular long axis using exactly the same angles for each individual patient. End-diastolic volume (EDV), ejection fraction (EF) and regional wall thickening (WT) were automatically calculated with the QGS algorithm. The root-mean-square difference (RMSD) between the five low-count realizations and the original high-count study were calculated for every noise level and evaluated in function of the total myocardial count density measured on the non-gated projections. Results: The total myocardial count density averaged 5.0+/-0.9 million counts in the original high-count studies. Using these original data, EDV, EF and WT averaged 117+/-15ml, 55+/4% and 34+/-4%, respectively. The RMSD of the EDV, EF and WT increased slightly with decreasing count levels until a total myocardial count density of 1.5 million counts. At that very low count level, RMSD was still below 6 ml for EDV and below 5% for EF and WT, respectively. Lower count levels generated unacceptable RMSD. Conclusion: QGS provides accurate and highly reproducible quantitative measurements of global and regional left ventricular function with gated myocardial perfusion tomographic studies containing as low as 1.5 million counts.

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24.07.2002

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n MYOCARDIAL PERFUSION SPECT - METHODOLOGY, QUALITY CONTROL P_117

P_119

E. Moralidis (1), T. Spyridonidis (2), G. Arsos (1), P. Vassilakos (2), K. Karakatsanis (1). (1) Nuclear Medicine Dept., Hippokration Hospital, University of Thessaloniki, Greece, (2) Nuclear Medicine Clinical Laboratory, Rio University Hospital, Patras, Greece.

K.H. Hwang, D.S. Lee, J.C. Paeng, W.J. Kang, J.-K. Chung, M.C. Lee. Seoul National University College of Medicine, Seoul, Korea.

Clinical evaluation of a novel lung thallium-201 uptake index

Aim: Lung 201Tl uptake (LTU) is traditionally measured as percentage of maximal 201Tl myocardial accumulation. A novel LTU index is evaluated in this study. Material and method: 104 patients (102 males, 2 females), aged 57±9 yrs, with suspected or known coronary artery disease (CAD) were recruited. All patients were submitted to routine exercise 201Tl SPECT imaging, and coronary angiography within 6 months from the perfusion study. Radionuclide ventriculography was performed in 75 of these patients. Post-stress images were used for the assessment of: a) the ischaemic area as percentage of the myocardial outline (summed ischaemic area, SIA) and b) the severity of myocardial ischaemia, by measuring both the area and the grade of perfusion abnormality (summed stress score, SSS). The traditional lung 201Tl uptake expressed as percentage of maximal myocardial 201 Tl accumulation from the anterior view was measured (L/H). The ratio of average lung 201Tl counts to the average whole heart net counts (background subtracted) was also calculated (L/Hnet). LVEF was calculated in the usual manner. Coronary artery lesions ≥50% were considered significant. Results: Both regression coefficients (r) and the slope (bnet) of the regression line were calculated for L/Hnet and LVEF (r=-0.33, p<0.005, bnet=-7.61), SSS (r=0.44, p<0.001, bnet=9.02) and SIA (r=0.44, p<0.001, bnet=4.02). Similar calculations were performed for L/H and LVEF (r=-0.28, p<0.05, b=-37.61), SSS (r=0.29, p<0.01, b=36.06) and SIA (r=0.33, p<0.01, b=18.06). In comparing L/Hnet and L/H, statistically significant difference was found between the slopes of SSS (p<0.05) and SIA (p<0.01), whereas marginally significant difference was found between the LVEF slopes (p=0.05). L/Hnet>1.90 and L/H>0.50 values taken as abnormal, both the positive predictive value (PPV) and the negative predictive value (NPV) of L/Hnet and L/H were assessed for left ventricular dysfunction (LVEF≤0.45), myocardial ischaemia severity (SSS>8), myocardial ischaemia extent (SIA>15%), and multivessel CAD (MVD):

LVEF SSS SIA MVD

L/Hnet PPV 67% 100% 100% 77%

NPV 71% 41% 21% 57%

L/H PPV 38% 87% 93% 60%

NPV 60% 39% 20% 55%

Efficacy of Attenuation Correction, Scatter Correction, and Resolution Recovery on Quantitative Myocardial SPET for Diagnosis of Coronary Artery Disease

Soft tissue attenuation and scatter are major methodological limitations of myocardial perfusion SPET. As a method to overcome these limitations, an algorithm for attenuation, scatter correction and resolution recovery (ASC-RR) has been developed. On the other hand, quantitative myocardial SPET became more available and widely used. In this study, we investigated the efficacy of an algorithm for ASC-RR on quantitative myocardial SPET in the diagnosis of coronary artery disease (CAD). A total of 74 patients who were suspected of CAD were enrolled in this study (M:F=50:24, age 61±9 yr). In all patients, Tl-201 rest/dipyridamole stress Tc-99m-MIBI gated myocardial SPET was performed and coronary angiography (CAG) was also performed 7±12 days before or after SPET. ASC-RR was applied using automatic software (Vantage; ADAC Labs, USA). Using a 20-segment model, segmental perfusion was automatically quantified on both the ASC-RR corrected and uncorrected images (AutoQUANT; ADAC Labs.). According to quantified values, CAD was diagnosed in each of the 3 coronary arterial territories. These results were compared with the results of CAG with setting 50% or more stenosis as significant lesion. Among 74 patients, 9 patients were normal on CAG and the other 65 patients had 154 arterial lesions; 60 left anterior descending (LAD), 48 left circumflex (LCX), 46 right coronary arterial (RCA) lesions. For LAD and LCX lesions, there was no significant difference of diagnostic value (p>0.05, Table). However, for RCA lesions, there was significant improvement of specificity with sacrifice of sensitivity when applying ASC-RR (p<0.05). Overall accuracy was not significantly changed. In conclusion, the ASC-RR did not make significant difference of diagnostic accuracy although there was significant improvement of specificity on quantitative myocardial SPET. The clinical application of the ASC-RR requires more considerations about cost and benefit.

LAD LCX RCA

Non-Correction Senstivity 73% 48% 65%

Specificity 36% 73% 57%

ASC-RR Sensitivity 73% 50% 35%

Specificity 64% 69% 86%

Conclusion: High and low values of the novel L/Hnet index are more closely associated with abnormal and normal values of parameters of myocardial ischaemia, severity of CAD and left ventricular systolic function, in comparison to the traditional L/H index. However, further investigation of the diagnostic and prognostic impact of this novel LTU index is warranted.

Lung thallium-201 uptake: An unreliable diagnostic index E. Moralidis (1), T. Spyridonidis (2), G. Arsos (1), P. Vassilakos (2), K. Karakatsanis (1). (1) Nuclear Medicine Dept., Hippokration Hospital, University of Thessaloniki, Greece, (2) Nuclear Medicine Clinical Laboratory, Rio University Hospital, Greece. Aim: Increased lung 201Tl uptake (LTU) is reported to be associated with left ventricular dysfunction and multivessel (MVD) coronary artery disease (CAD). Despite its well established prognostic value, its diagnostic potential is unclear. This study investigates the diagnostic significance of LTU. Material and method: 104 patients (102 males, 2 females), aged 57±9 yrs, with suspected or known CAD, were enrolled. Patients were submitted to dynamic exercise stress-redistribution 201 Tl SPECT imaging, and coronary angiography within 6 months from the nuclear test. Radionuclide ventriculography was performed in 75 of these patients. Stress images were used for semiquantitative perfusion assessment by two experienced observers. The ischaemic area as percentage of the myocardial outline (summed ischaemic area, SIA) and the severity of myocardial ischaemia, by combining both the area and the grade of perfusion abnormality (summed stress score, SSS), were calculated. Lung 201Tl uptake expressed as percentage of maximal 201Tl accumulation in myocardium from the anterior view was also measured (L/H index). LVEF was calculated in the usual manner. Coronary artery stenoses ≥50% were considered significant. Results: Angiography was normal in 6 individuals, 49 patients had 1-vessel disease (1VD), and 49 patients had MVD (29 pts with 2VD, and 20 pts with 3VD). There was no significant difference in L/H between the 49 patients with MVD (0.41±0.08), the 49 patients with 1VD (0.38±0.08) and the 6 individuals with normal coronaries (0.36±0.07) (Kruskal-Wallis). Similarly, no significant difference was found in L/H between the 47 patients with LVEF>0.45 (0.39±0.08) and the 28 patients with LVEF≤0.45 (0.42±0.10) (Mann-Whitney U). A poor linear correlation was found between L/H and LVEF (r=-0.28, p<0.05), SSS (r=0.29, p<0.01) and SIA (r=0.33, p<0.01). Taken LVEF≤0.45, SSS>8, SIA>15% and L/H>0.50 values as limits of abnormality, both the positive predictive value (PPV) and the negative predictive value (NPV) of L/H were calculated for: 1) LVEF: PPV=38%, NPV=60%. 2) SSS: PPV=87%, NPV=39%. 3) SIA: PPV=93%, NPV=20%. 4) MVD: PPV=60%, NPV=55%. Conclusion: 1) Normal L/H values do not necessarily imply preserved LVEF and abnormal L/H values do not necessarily indicate decreased LVEF. 2) Although abnormally elevated L/H values may be associated with severe myocardial ischaemia and MVD, normal L/H values cannot rule out their presence. 3) L/H measurement is an unreliable diagnostic index and should not affect myocardial perfusion interpretation or replace direct LVEF calculation.

P_120

The influence of chocolate eating and post-injection time interval on 99mTc MIBI myocardial images quality O. Lang (1), R. Pichova (1), I. Kleisner (1), M. Mala (1), F. Malek (2), P. Jebavy (3), M. Kaminek (4), M. Myslivecek (4). (1) Department of Nuclear Medicine, Charles University, 3rd Medical Faculty, Prague, Czech republic, (2) Department of Internal Medicine, Charles University, 3rd Medical Faculty, Prague, Czech republic, (3) Kardiologie na Bulovce Ltd, Prague, Czech republic, (4) Department of Nuclear Medicine, Palacky University, Medical Faculty, Olomouc, Czech republic. Aim: 99mTc MIBI is excreted through the biliary system so it can negatively influence tomographic reconstruction of myocardial perfusion images. Recommended time to postpone image acquisition can negatively influence patient throughput. The aim of our study was to assess use of chocolate as an alimentary biliary stimulus for stress myocardial perfusion images quality at different post-injection time intervals. Materials and methods: We evaluated 190 consecutive patients, 78 women and 112 men, referred to our department for myocardial perfusion imaging (MPI). All pts were stressed with bicycle or dipyridamole combined with bicycle and were injected with 300 to 400 MBq of 99mTc MIBI according to weight. Pts were divided into two groups depending on eating or not 50 g of chocolate during 10 minutes after injection at peak stress. Image acquisition on single-head SPECT gamma camera was postpone to three time intervals, t20 (20-25 min.), t30 (30-35 min.) and t40 (40-45 min. after injection). Image quality was evaluated by the heart/liver ratio of counts/pixel using commercial software (circular ROI, first acquired image). ANOVA with F test and Kruskal-Wallis analysis with chi-square test were used for statistical analysis. Results: The worse heart/liver ratio had pts who eat chocolate and were acquired at t20, the best heart/liver ratio had pts who eat chocolate and were acquired at t40 – see table below. Heart/liver ratio in pts who did not eat chocolate did not differ significantly irrespective to post-injection time interval. time n mean H/L std. dev. mean rank statistics

pts with chocolate pts without chocolate t20 t30 t40 t20 t30 t40 53 20 37 18 27 35 0.490 0.554 0.980 0.583 0.591 0.586 0.136 0.169 0.348 0.172 0.144 0.140 61.802 78.625 157.108 89.555 94.574 94.814 ANOVA: F=28.484, p<0.000; Kruskal-Wallis: chi-square=68.448, p<0.000

Conclusion: We recommend for patients to eat 50 g of chocolate and to postpone data acquisition to 40 to 45 minutes after injection of 99mTc MIBI at peak stress in stress MPI according to our results.

S219

Poster Presentation

P_118

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n MYOCARDIAL PERFUSION SPECT - METHODOLOGY, QUALITY CONTROL P_121

Operatordependent variability in quantitative analysis of reversible myocardial perfusion defects L.Å. Åkesson. Department of Clinical Physiology, Malmö, Sweden. Aim. Myocardial perfusion SPECT imaging is used to assess the perfusion of the myocardium. The size of a perfusion defect and its reversibility can be quantified by the CEqual software (Cedars Emory quantitative analysis). The software produces quantitative analyses for the extent and reversibility of the defect. The processing from raw images to the final CEqual display, is performed by a medical laboratory technologist and consists of a number of manual steps, which could cause problems of variability between operators. The aim of this study was to evaluate the variability in the results of the quantitative analysis between experienced operators. Methods. Thirteen patients who underwent a myocardial perfusion SPECT using 99m Tc Tetrofosmin were selected. The material included three patients with normal perfusion, five with large fixed apical defects and five with reversible defects in the apical area. Eight experienced medical laboratory technologist processed the studies. They started from raw projection data and created short axis slices by defining two alignment axes parallel to the long axis of the left ventricle. The short axis slices were used as input to the CEqual software. The operators created the polar plot images by aligning the short axis slices in the rest and stress studies and thereafter selecting the apical and basal slices in the two studies. Results. The extent of the reversible defects for each patient and each of the three vascular territories (LAD, LCX , RCA) was presented as percentage of the total vascular territory. The mean extent of reversibility for the eight operators was calculated for each patient and each territory. To determine the variability between the operators the eight differences from the mean value was used to calculate the standard deviation. Results are presented as 2 standard deviation. The largest variability in quantification of reversibility between operators was found in the patient group with reversible apical defects (LAD 6.4 %, LCX 9.2 %, RCA 10.0 %). For one patient the reversibility in LCX was 0, 6, 39, 18, 1, 31, 16, 41 % for the eight operators, respectively. Patients with fixed apical defects showed slightly less variability (LAD 8.2 %, LCX 2.4 %, RCA 2.4 %). The least variability was found in patients with normal perfusion (LAD 2.9 %, LCX 2.8 %, RCA 3.2 %). Conclusion. Large variability between experienced operators quantifying reversible defects using the CEqual software was shown. The variability was largest in patients with reversible defects but was also found in patients with normal perfusion. Physicians may therefore consider the results of a quantitative analysis.

P_122

Effect of stress on myocardial kinetics of 201Tl injected at rest P. Weinmann (1), P. Hannequin (2), J.L. Moretti (1). (1) Avicenne Hospital, Bobigny - FRANCE, (2) Centre d’Imagerie Nucleaire d’Annecy, France. Aim: In separate dual isotope myocardial SPECT, a rest single 201Tl acquisition is followed by a stress single 99mTc sestamibi acquisition. In simultaneous dual isotope myocardial SPECT, only one dual acquisition is performed with the following sequence :201Tl rest injection – 99mTc sestamibi stress injection and dual 201Tl/99mTc acquisition. However, after administration of 201 Tl at rest, the influence of a stress test on 201Tl myocardial kinetics has never been studied in humans. In this study, we investigated the effect of stress on 201Tl injected at rest. Methods: 5 patients (4 men, 1 woman, 59 ± 3.8 yr) underwent a first 201Tl SPECT after rest injection of 150 MBq 201Tl followed by a stress test without any tracer injection : 3 exercise tests (EX), 2 dipyridamole infusions combined with exercise (DIP). A second 201Tl SPECT acquisition was performed 60 minutes later. Acquisition parameters were checked to be identical in every patient. A visual analyzis was performed by two independent observers and the following parameters were analyzed : location and intensity of defects (five-level scale) ; location of maximal myocardial uptake ; presence, location and intensity of intestinal background. A comparison was then performed between the two separate data sets. Results: On the first 201Tl SPECT, 2 patients had a normal scan, 2 patients a mild defect and 1 patient exhibited a defect with no 201Tl uptake. On the second 201Tl SPECT, EX did not have any influence on 201Tl SPECT in two patients. In a third patient, EX resulted in near disappearance of intestinal background. In a fourth patient, DIP resulted in near disappearance of intestinal background and a shift of maximal myocardial uptake from lateral wall to septum. In a fifth patient, DIP induced near disappearance of intestinal background, a one level increase in intensity of an inferior defect and revealed the presence of a moderate apical defect. In this patient, a separate dual isotope procedure performed 3 days earlier had displayed moderate apical and inferior ischemia on sestamibi images. Conclusion: This study indicates that stress test may alter myocardial kinetics of 201Tl previously injected at rest and modify intestinal background level. In one patient out of five, stress induced a defect in a probably ischemic region. These findings should have important implications when performing simultaneous dual isotope myocardial SPECT.

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P_123

Sensitivity of Tc-99m-MIBI SPECT in the detection of coronary artery disease (CAD): the role of the increase in the heart rate during exercise M. Kaminek (1), M. Myslivecek (1), V. Husak (1), P. Koranda (1), I. Metelkova (1), M. Skvarilova (2), J. Ostransky (2), O. Lang (3). (1) Dept. of Nucl. Med., University Hospital, Olomouc, (2) Dept. of Internal Med. I, University Hospital, Olomouc, (3) Dept. of Nucl. Med., University Hospital, Prague-Vinohrady, Czech Republic. A failure to achieve W85% of the age predicted maximal heart rate (HR) is traditionally known as a source of false-negative SPECT results. A pharmacological stress is generally preferred in this case. However, the recent literature has suggested a sufficient increase in the HR (the difference between basal and maximal HR>60 bpm) to be more important criterion for the adequate exercise. Aim: To assess the role of the increase in the HR for the detection of CAD by SPECT and to compare sensitivity of exercise and pharmacological stresses for the identification of coronary stenoses of intermediate severity. Methods: Sample of 345 patients without prior myocardial infarction (110 women, average age 56 years, range 36-79) referred to the detection of CAD by Tc-99m-MIBI SPECT was analysed retrospectively. 292 patients underwent the symptom limited bicycle exercise. Dipyridamole was used in 53 patients unable to exercise. Two independent observers evaluated ischaemia as a reversible perfusion defect on SPECT. CAD was defined as a W50% luminal diameter stenosis. Results: The sensitivity and specificity of SPECT in the whole sample of patients was 90% (191/212) and 94% (125/133), respectively. SPECT dipyridamole sensitivity was 90% (38/42) and the same sensitivity 90% (153/170) was found in the exercise group. A more detailed analysis of the exercise group is in table. Exercise group (n=292)

W85% maximal HR bpm No Yes Sensitivity of SPECT (P = NS) 92% 89% (68/74) (85/96)

Increased HR>60 + increased HR No Yes 88% 92% (75/85) (78/85)

<85% maximal HR >60 bpm 95% (19/20)

Stenoses of intermediate severity (stenoses with <70% narrowing, n=25) were identified by the dipyridamole SPECT in 50% of patients only (3/6). The exercise SPECT exhibited higher sensitivity 74% (14/19). Those of them with the increase HR>60 bpm had sensitivity 78% (7/9, P=NS). Conclusions: The failure to achieve W85% of the age predicted maximal HR at exercise does not necessarily mean the lower sensitivity of SPECT. Although in 74 CAD patients the exercise was stopped before reaching this level (the chest pain was the main limitation), the sensitivity was higher. Our results confirmed the considerable increase in HR as an important criterion for adequate exercise. The exercise (especially when the increase in HR>60 bpm) was more helpful to identify the stenoses of intermediate severity in comparison with dipyridamole.

P_124

Reverse perfusion pattern in Tc99m-tetrofosmin myocardial perfusion scan using 2-day protocol K.C. Cheng, W.Y. Ho, E.Y.L. Leung, K.K. Wong, T.H. Ho, R.Y.L. Leung, M.L. Yip, T.C. Chan, S.S. Leung. Nuclear Medicine Unit, Department of Radiology, Queen Mary Hospital, Hong Kong, China. Aim: Reverse perfusion pattern refers to myocardial perfusion defect that develops or becomes more evident in resting images compared with post-stress images. This retrospective study evaluated the incidence and the clinical implications of reverse perfusion pattern in Tc99m-tetrofosmin myocardial perfusion scan. Materials and Methods: 957 Tc99m-tetrofosmin myocardial perfusion scans using 2-day protocol were reviewed. Comparison was made between the post-stress and resting images; the segments demonstrating reverse perfusion pattern were correlated with coronary angiography findings or clinical follow-up. Results: 25 patients (16 males, 9 females; mean age 60.2) demonstrated reverse perfusion pattern with overall incidence of 2.6%. These patients had no history of myocardial infarction and were referred for suspected ischemic heart disease. 12 patients had exercise treadmill stress and 13 patients had dipyridamole pharmacological stress. 7 patients had coronary angiography performed with normal findings in 5 patients and no evidence of hemodynamically significant coronary artery stenosis in another 2 patients. They presented as 9 defects including 3 anterior, 1 apical, 1 inferoapical, 1 anteroseptal, 1 inferoseptal, and 2 inferior defects and diagnosed as normal variants. Rest of the 18 patients revealed no other associated perfusion abnormalities (except 1 patient had a small-sized reversible mild anterior perfusion defect) and they had uneventful clinical follow-up ranged from 2 to 16 months (mean 7.7 months). These 21 defects were attributed as normal variants, including 6 anterior, 10 inferior, 1 inferoapical, 1 anteroseptal, 1 septal, and 2 apical defects. Conclusion: Reverse perfusion pattern is not commonly found in Tc99m-tetrofosmin myocardial perfusion scan using 2-day protocol. It can be normal variants and offers no additional predictive value in the diagnosis of coronary artery disease in patients without prior myocardial infarction.

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n MYOCARDIAL PERFUSION SPECT - METHODOLOGY, QUALITY CONTROL Pulmonary Uptake of Tc-99m MIBI In Type II Diabetic Patients:A Comparative Study with Non-Diabetics O. Omur (1), A. Dirlik (1), E. Acar (1), M. Argon (1), Z. Danalioglu (2), O. Ozyurt (1), Z. Ozcan (1). (1) Department of Nuclear Medicine of Ege Univercity Medical Faculty, (2) Department of Cardiology of Ege Univercity Medical Faculty. Izmir, Turkey. Aim: Increased pulmonary uptake of Tl-201 is recognised as an important indicator of left ventricular dysfunction. In the current study, it was aimed to investigate the value of pulmonary Tc-99m sestamibi uptake as a marker of coronary artery disease in patients with and without diabetes mellitus (DM). Methods: 50 type II DM and 35 non-DM patients were studied. All data were collected by two day stress-rest Tc-99m MIBI protocol. 61 patients underwent treadmill exercise, 24 patients received dipyridamole as a stress agent. Additional anterior planar thorax images were taken at 30 minutes after stress injection. Lung/Heart (L/H) ratios were calculated using ROI analysis. Myocardial perfusion SPECT (MPS) results and L/H ratios were correlated with clinical findings and cardiac tests. Mode of exercise was also examined as a factor affecting pulmonary MIBI uptake. Results: L/H value were ranging between 0.23 – 0.64 in whole study population with a significantly higher ratio in patients with abnormal MPS (MPS +) than patients with normal MPS (MPS -). L/H ratios for DM and non-DM groups are shown below:

P_127

Time course assessment of the myocardial perfusion delayed images and the cardiac function before and after reperfusion therapy for AMI using 99mTc-SESTAMIBI gated SPECT R. Tanaka (1), T. Nakamura (2), H. Kumamoto (2), K. Hirabayashi (2), N. Okamoto (3), K. Fujita (2). (1) Department of Radilogy, Kushiro-ishikai Hospital, Kushiro, Japan, (2) Department of Circulator, Kushiro-ishikai Hospital, Kushiro, Japan, (3) Bristol-Myers Squibb K.K., Kushiro, Japan.

No relationship could be found between mode of stress and L/H value. A significant correlation was noted between L/H and multivessel disease pattern in non-DM patients. In diabetic population, no significant relation could be found between L/H value and duration of disease and systemic diabetic complications. Conclusion: Our results imply that increased pulmonary uptake of sestamibi is associated with presence myocardial perfusion defects. Significantly higher L/H ratios were found in diabetic cases than non-diabetics both for normal and abnormal MPS groups. Therefore, we suggest further studies are indicated for the assessment of other mechanisms unrelated to the myocardial perfusion contributing to increased L/H ratio in diabetic cases.

Aim : Cardiac dysfunction after myocardial ischemia-reperfusion is called stunned myocardium, and its recovery is considered to take longer time than the recovery of the myocardial perfusion images. In the present study, we have investigated the relationship between the changes of myocardial perfusion delayed images obtained by using 99mTc-SESTAMIBI (MIBI) after AMI reperfusion and the improvement of the cardiac function. Methods: 99mTc-SESTAMIBI (MIBI) SPECT images before reperfusion (pre-images) using the freezing method were obtained from a total of 25 patients with acute myocardial infarction (AMI). In addition, early images (images obtained 30 minutes after the injection) and delayed images (images obtained 6 hours after the injection) on days 1, 7, 20, and 60 after the reperfusion were taken. The percent uptake was calculated, and the segments less than 60% were considered as the abnormal area. Furthermore, the cardiac function was also analyzed with Gated SPECT utilizing QGS program. Results: Regarding the changes in the number of the abnormal area (NAA), remarkable improvement of the early images was consecutively observed from the pre-images through day-7 images (p<0.001), but no significant improvement was observed after day 7 (ns). On the contrary, there were no significant differences in the delayed images of NAA from day 1 through day 7, but significant improvement was observed from day 7 to day 60 (p<0.05). To assess the cardiac function, regional wall motion, and regional wall thickening were measured using the QGS program, and the rate of improvement in the cardiac function from day 7to day 60 was evaluated. The rate of improvement in the regional wall motion and regional wall thickening was significantly correlated with that in the NAA of delayed images obtained from day 7 to day 60 (r=0.492, p<0.01,) (r=0.562, p<0.01,). Thus, the improving pattern of the cardiac function was more similar to that of MIBI delayed images than that of the early images. Conclusions: Reverse redistribution, which is observed through the MIBI myocardial perfusion delayed image after AMI reperfusion, is known to be involved in the membrane potential of the mitochondria, which suggests a possible link with ATP production in the mitochondria. Our results suggest that the use of MIBI delayed images may be helpful for assessment of the recovery from stunned myocardium.

P_126

P_128

K.C. Cheng, W.Y. Ho, E.Y.L. Leung, K.K. Wong, T.H. Ho, R.Y.L. Leung, M.L. Yip, T.C. Chan, S.S. Leung. Nuclear Medicine Unit, Department of Radiology, Queen Mary Hospital, Hong Kong.

M. Erkiliç, G. Bural, I.O. Çeri. Department of Nuclear Medicine, Akdeniz University School of Medicine, Antalya, Turkey.

Non-DM DM Significance (p)

MPS (+) 0.40±0.10 0.46±0.08 p<0.05

MPS (-) 0.33±0.05 0.42±0.08 p<0.05

Significance (p) p<0.05 p>0.05

Right ventricle insertion artifact in Tc99m-tetrofosmin myocardial perfusion SPECT scan

Aim: Right ventricle insertion artifact is sometimes seen in myocardial perfusion SPECT scan with pattern of small focal decreased myocardial perfusion tracer uptake in the area of insertion of right ventricle into the left ventricle. The artifact is more commonly visualized in technetium labeled agents like sestamibi or tetrofosmin compared with thallium due to the better imaging quality and resolution. This study evaluated how frequent and where the artifacts were observed in Tc99m-tetrofosmin myocardial perfusion scans. Materials and Methods: The myocardial perfusion scans of 270 patients (112 men and 158 women; range of age 24 to 97 years with mean 61 years) were evaluated retrospectively. They had two-day stress/rest Tc99m-tetrofosmin SPECT scans performed. The presence and location of small focal cleft of decreased tracer uptake in the area of insertion of the right ventricle into the left ventricle in both sets of stress and rest images were noted. Gated SPECT images were correlated for regional myocardial thickening. Results: 17 right ventricle insertion artifacts were identified in 17 patients (6.3%; 9 women and 8 men). 9 patients had exercise treadmill stress and 8 patients had dipyridamole pharmacological stress. All defects demonstrated good regional myocardial thickening in gated SPECT images. 15 defects (88%) were located in the anteroseptal wall with 8 defects in distal anteroseptal wall and 1 defect in proximal anteroseptal wall only. The artifact was less frequently seen in inferoseptal wall (n=2; 12%). Conclusion: Right ventricle insertion is an artifact encountered in Tc99m-tetrofosmin myocardial perfusion scan. It is usually seen in anteroseptal wall and less frequently in inferoseptal wall. The artifact can be differentiated from scar tissue by good regional myocardial thickening in gated SPECT images.

The Estimation of Cardiac Stress Test Efficiency by Tc99m-MIBI Scintigraphy.

Aim: After stress test the myocardial blood flow should be increased in sufficient amount to get healthy information about myocardial perfusion. The increase of blood flow after different stress tests ( threadmill exercise, dipyridamole ) were evaluated by Tc99m-MIBI scintigraphy. Material and Methods: 50 cases ( 30 exercise, 20 dipyridamole ) were included in this study. After standart treadmill exercise test ( Standart Bruce ), Dipyridamole ( 0,56 mg/kg/4 min. ) cardiac SPECT images (7 mCi Tc99m-MIBI ) after 1 hour ( 180 degree, 25 sn/step ,DualCam Siemens ) and rest images 45 min. after 21 mCi Tc99m-MIBI injection using same protocol but 30 sn/step were taken. Using Butterworth filter 0.5 cut-off, frequency 5 transaxial images were obtained. On these images ( post-stress and rest ) , a rectangular ROI were placed in normal myocardial area. After background, injected dose, imaging time interval and decay corrections, Post-stress / rest (PS/R) ratio were calculated as an index of increase in myocardial blood flow . Results: In exercise group PS/R ( mean ± SD ) = 1,6 ± 0,16 , Dipyridamole group = 2,3 ± 0,31 were found. The increase in myocardial blood flow of dipyridamole group was greater than exercise group and statistically different ( p<0.01 ). Conclusion: PS/R ratio seems an useful and simple index to evaluate the efficiency of stress test used during Tc99m-MIBI myocardial perfusion scintigraphy. Dipyridamole should be preferred as a stress test because of its greater effect on myocardial blood flow.

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n MYOCARDIAL PERFUSION SPECT - METHODOLOGY, QUALITY CONTROL P_129

Changes in serum myoglobin level as a marker of myocyte damage following combined exercise and adenosine stress testing for radionuclide myocardial perfusion imaging. C.Y. Loong (1), M. Kemp (2), S.L. Rahman (1), E. Reyes (1), M. Harbinson (1), S.R. Underwood (1). (1) Department of Nuclear Medicine, Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK, (2) Department of Clinical Biochemistry, Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK. Aim. Serum myoglobin is a sensitive marker of myocyte damage. There are no published data on the safety of combined exercise/adenosine stress test with regard to possible myocyte damage. We have measured serum myoglobin levels after such stress. Method. Patients referred for myocardial perfusion imaging were recruited from May to November 2001. Incremental dynamic bicycle exercise was performed until achievement of target heart rate (85% of 220 minus age for men or 210 minus age for women) or symptoms requiring termination. Intravenous adenosine (140 µg/kg/min) was given for 6 minutes during exercise. Intravenous thallium-201 (80 MBq) was given 3 minutes after start of adenosine, to coincide with peak exercise. Immediately after stress, images were acquired on a gamma camera. After 3-4 hours, rest images were acquired. Venous blood was taken at baseline, after stress image acquisition (“poststress”) and after rest image acquisition (“postrest”) for myoglobin immunoassay. Scintigrams were interpreted by a blinded reporter. Myoglobin levels were compared using paired two-tailed t test. Data are presented as mean ± SD (age and times) or mean difference ± standard error (changes in myoglobin levels). Results. Seventy three patients (48 males; age 65.7 ± 10 years) completed the study; 36 (49.3%) had known coronary disease. Only 23 patients (31.5%) reached target heart rate, but 30 (41.1%) had inducible ischaemia. The time from taking baseline to poststress bloods was 44.6 ± 19.9 mins, while the time from baseline to postrest bloods was 203.6 ± 45.4 mins. Change in myoglobin level from baseline to poststress was –2.7 ± 1 µg/l (p=0.0073), while that from baseline to postrest was –5.4 ± 1.4 µg/l (p=0.0002). No patient had a clinically significant myoglobin rise (defined as twice the upper limit of laboratory reference range [970µg/l]); 4 had peak myoglobin levels outside this range (101, 103, 113 and 122 µg/l). Conclusions. There was a small but statistically significant fall in myoglobin level after combined exercise/adenosine stress. This may reflect unknown technical variables with myoglobin measurement. Importantly, there was no rise. Because serum myoglobin level rises soon after myocyte necrosis, this study provides biochemical evidence of the lack of myocyte necrosis during such stress.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition MYOCARDIAL PERFUSION SPECT - CLINICAL

P_130

Myocardial perfusion by means of MIBI SPECT in children after anatomical correction of the TGA B. Malkowski (1), Z. Maziarz (1), W. Tryniszewski (1), A. Dedecjus-Sysa (2), J. Moll (2). (1) Department of Nuclear Medicine Military Medical University, Lodz, Poland, (2) Cardiology Clinic ICZMP, Lodz, Poland. Anatomical correction in treatment of complete transposition of great arteries (TGA) is a method of choice. Aim: Because the transfer of coronary arteries to neoaorta is the most crucial and difficult problem during this operation we investigated the long term myocardial perfusion in this group of children. Materials and methods: 310 children were operated on between 1991 and 2000 and among them 29 (9%) underwent the MIBI SPECT 4 –9 years after the operation. Myocardial perfusion scintygraphy was performed in rest, 60 min. after the injection of 11,1MBq/kg 99mTc MIBI. Acquisition were performed on ELSCINT SP6HR gamma-camera. Assessments were made using four –grade scale, dividing left ventricle on 13 segments Results:In 21 (75%) myocardial perfusion was normal but in 6 cases several defects of perfusion occurred, whereas in 3 patients there was no perfusion in the basic segment of myocardial septum because of large path. In the course scintygraphy examinations by means of USG Doppler were also performed showing normal results of total contractility. Conclusion: Based upon the long-term assessment it may be assumed that most patients after anatomical correction of great arteries have no myocardial perfusion disorders. However, the local perfusion defects are an indication to further observation and coronary angiography because of the possibility of gradual aggravation of myocardial perfusion defects.

P_131

Prognostic value of Tc-99m tetrofosmine SPECT in patients after acute myocardial infarction V. Chernov, S. Salpagarova, YU. Zajblov, YU. Lishmanov. Institute of Cardiology, Tomsk, Russia. Aim: The aim of this study was to estimate the prognostic value of size and severity of perfusion defects in patients (pts) after acute myocardial infarction (AMI) by adenosine (A) – rest (R) Tc-99m tetrofosmine SPECT, in comparison to angiography, echocardiography and bicycle test. Methods: 210 CAD pts (195 males and 15 women, mean age 52±8) were underwent A-R Tc99m tetrofosmine SPECT, angiography, echocardiography and bicycle test 3-4 weeks after AMI. The next indices were assessed: A (ADS) and R perfusion defect size (RDS), integral indices of A (IIAD) and R (IIRD) perfusion defect, as well as ejection fraction (EF) and exercise tolerance (ET). A cardiac event was defined as either cardiac death (CD), nonfatal AMI, unstable angina requiring further revascularization (UA). Results: During an average follow-up of 24+5 months all pts were divided into two groups: Gr.1 (138 pts) with benign current of disease and Gr.2 (72 pts) with cardiac events (8 - CD, 12 - AMI and 52 - UA). The myocardial perfusion parameters in these patients are presented in the Table. Indices ADS (%) RDS (%) IIAD (%) IIRD (%)

1 Gr. M+m 22,8+1,1 17,1+1,0 4,4+1,0 5,5+0,5

2 Gr. M+m 31,3+2,2 26,5+2,1 7,1+2,1 8,6+1,1

p 0,0001 0,0001 0,001 0,001

F 19,2 23,4 10,9 11,2

R2 0,09 0,13 0,06 0,06

The three vessel disease, low level of EF and ET had own prognostic value, but did not add prognostic value to 99mTc-tetrofosmine SPECT. Conclusion: The extensive sizes of perfusion defects at rest and at peak of adenosine test was shown to predict future cardiac events. Angiography, echocardiography and bicycle test had own prognostic value, but did not add prognostic value to 99mTc-tetrofosmine SPECT.

P_132

Improvement of myocardial perfusion after lipid-lowering therapy in patients with coronary atherosclerosis J.P. Wielepp (1), D. Baller (2), A. Kammeier (1), E. Pulawski (2), R. Weise (1), W. Burchert (1). (1) Institute of Mol. Biophysics, Radiopharmacy and Nuclear Medicine, (2) Department of Cardiology, Heart- and Diabetes Center Bad Oeynhausen, Bad Oeynhausen, Germany. The early stage of coronary atheroscleorsis is characterized by a functional impairment of the flow regulation under the impact of risk factors such as hypercholesterolemia. This study investigated the effects of lipid-lowering therapy on coronary perfusion in myocardial regions having substantial impairment of pretreatment vasoregulation. Material and Methods: We investigated 12 patients (mean age 64.5 ± 6 years; 8m, 4f) with multivessel coronary disease (group A, n=5) and minimally diseased coronary vessels (group B, n=7) by PET for myocardial blood flow (MBF) measurment with 13N ammonia at rest and under dipyridamole (D) stress (0.56mg/kg) before and after lipid –lowering therapy with atorvastatin (10 - 80mg/d) for 6 ± 4 months. The evaluation of the regional MBF was performed using a 20 segment model. Myocardial segments were classified on the basis of pretreatment MBF response to dipyridamole as normal (>190ml/min/100g) or abnormal (<190ml/min/100g). Results: Atorvastatin reduced LDL from 200 ± 46 mg/dl to 99 ± 27 mg/dl (p<0.0001). In normal segments MBFstress and minimum coronary resistance (MCR) were unchanged after atorvastatin. In abnormal segments, MBFstress increased significantly in both groups. MCR declined significantly to nearly normal values in group B. Concomitantly, a regression of anginal symptoms was observed in most patients. abnormal segments MBFstress (ml/100g*min) MCR (mmHg*100g*min)/ml *p<0,001

Group A baseline

after 6 months

Group B baseline

after 6 months

141± 32

179*± 32

167± 15

244*± 42

0,68± 0,17

0,57*± 0,17

0,56± 0,08

0,38*±0,08

Conclusion: Lipid-lowering therapy improves significantly the MBF response under D-stress and MCR in most impaired myocardial segments in early stages of atherosclerosis. The results suggest that lipid lowering therapy is considered a vasoprotective treatment for selected patients in early stages of coronary atherosclerosis with the potential of preventing further disease progression.

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n MYOCARDIAL PERFUSION SPECT - CLINICAL P_135

Pace-induced reversible ischemic left ventricular dysfunction in patients with one vessel coronary artery disease

Incremental prognostic value of gated SPECT myocardial perfusion scintigraphy in patients with left bundle branch block.

R. Roszczyk (1), E. Dziuk (2), J. Adamus (1), E. Sztwiertnia-Roszczyk (1), P. Snigurowicz (1), J. Janczak (1), D. Borkowski (3), A. Roszczyk (1), R. Czarnecki (1). (1) Cardiology Department, Central Military Hospital, Warsaw, Poland, (2) Department of Nuclear Medicine, Central Military Hospital, Warsaw, Poland, (3) Cardiosurgery Department, Central Military Hospital, Warsaw, Poland.

J.J.J. Borm (1), Y.G.C.J. America (1.), E.E. van der Wall (2.), E.K.J. Pauwels (1.). (1) Department of Radiology Division of Nuclear Medicine, Leiden University Medical Center, (2) Department of Cardiology, Leiden University Center, Leiden, The Netherlands.

AIM: The purpose of this study was a quantitative estimation of global left ventricular ejection fraction (LVEF) changes during the rapid left atrium pacing (RLAP) in patients (pts) with coronary artery disease (CAD) with significant or nonsignificant diameter stenosis of the left anterior descending artery (LAD). METHODS: 130 pts (F – 46, M – 84) aged 29 – 70; mean 52.4 ± 7.4 year old were included into this study. Pts were divided into two groups (A and B). Group A was represented by 64 pts with stable CAD without myocardial infarction in history and with significant (≥50%) diameter stenosis of LAD in the following segments: proximal – 29, middle – 24 and distal – 21 pts. Group B was made by 66 pts with typical chest pain and nonsignificant (<50%) diameter stenosis of LAD. LVEF was estimated at rest, during and immediately after discontinuation of RLAP by quantitative gated radionuclide angiocardiography (GRA). A decrease of LVEF value over 5% of primary value (at rest) was approved as a significant for myocardial ischemia. RESULTS: LVEF mean values at rest, during and immediately after RLAP for both groups of pts are presented in the table below. 95% of pts from group A and 88% of pts from group B demonstrated an essential decrease of LVEF during the peak RLAP (20% decrease of LVEF approximately). LVEF mean values between groups differ significantly only after RLAP. CONCLUSIONS: There was no difference between LVEF mean values at rest and during RLAP in pts with and without significant stenosis in one vessel (LAD).In patients from group A there was not a complete normalization of LVEF after RLAP. This non-invasive test did not differ ischemic reversible left ventricular dysfunction in pts with CAD and significant or nonsignificant diameter stenosis of LAD. GROUPS

mean LVEF [%] 1. at rest 2. pacing A. ≥ 50% LAD 64.8 ± 5.2 44.6 ± 7.1 stenosis B. <50% LAD 65.2 ± 6.1 46.4 ± 8.4 stenosis p value NS NS p<0.01

3. after pacing 54.2 ± 6.2 64.8 ± 7.9

p value 1 vs. 2 p<0.001 1 vs. 3 p<0.05 1 vs. 2 p<0.001 1 vs. 3 NS

P_134

Scintigraphic evaluation of perfusional myocardial changes induced by dipyridamole in patients affected by slow coronary flow phenomenon G. De Vincentis (1), G. Tanzilli (2), F. Scopinaro (1), S. Remediani (1), G. Di Santo (1), R. Di Placido (2), C. Comito (2), E. Mangieri (2). (1) Department of Experimental Medicine Section of Nuclear Medicine University of Rome La Sapienza, Rome, Italy, (2) Department of Cardiosurgical Sciences Cardiological Unit University of Rome La Sapienza, Rome, Italy. The phenomenon of slow coronary artery flow (SCF) is characterized by a slow anterograde progression of the dye on the coronary arteriogram. Dipyridamole (D), which has dilator properties on coronary microvessels, has proved to be useful in the normalization of angiographically determined SCF and has been proposed as a therapeutical agent for treatment of such pathology. Aim of this work was to assess myocardial perfusion changes induced by D administration. 5 patients with angiographically proven SCF were studied in two separate days by myocardial 99mTc Sestamibi (S) scintigraphy. 740 MBq of tracer were i.v. administered at rest and after i.v. administration of D at the dose of 0.56 mg/Kg (the same used during angiography). No significant changes of blood pressure and heart rate were observed. 15 minutes after injection, planar views were acquired in LAO 45, anterior and left lateral projection with a prefixed acquisition time. Immediately after, the scan was repeated by SPET technique. Region of interest (ROI) were drawn on the myocardial regions taken into account: antero-lateral and postero-septal, postero-lateral and antero-septal, anterior and inferior wall. The same ROI on the same wall at rest and D scans was used. Total ROI counts were determined to calculate the relative difference between opposite wall in the same view and expressed as counts ratio value (P). P was used to compare rest and D scans. No P significant differences existed in myocardial areas served by normal arteries. D scan showed a scintigraphic perfusion defect in areas dependent from SCF arteries: as a consequence in the planar projection where the defect was appreciable, a strong increase of P was measured. These data were qualitatively confirmed by SPET images. These results suggest that normalization of coronary flow arteriographically obtained by D, does not correspond to improvement of myocardial perfusion. Actually we obtained a scintigraphic pattern of myocardial ischemia. These data well correlates with the clinical and ECG appearance of this phenomenon.

Aim: To asses the incremental prognostic value of myocardial perfusion scintigraphy [MPS] with quantitative gated SPECT [QGS] in patients with left bundle branche block [LBBB]. Methods: Long term follow-up study in consecutive patients who underwent routine MPS. Inclusion criteria: first QGS study with LBBB at rest, from November 1997 until January 2000;107 out of 1168 patients. Census date for follow-up was April 1st 2000. Analysis by means of Cox regression analysis. Endpoints: death; myocardial infarction, ECG-documented ventricular fibrillation. For wall motion and wall thickening analysis, a 20 segment model and a division in anteroseptal and inferolateral regions were used. Results: Age: 65+ 9 y [range 44-84y]; male 66%; Riskfactors: previous infarction [MI] 38%; previous revascularization 22%; cardiac resuscitation 10%. Reason for referral: de novo anginal complaints: 27%; asymptomatic: 10%; established coronary artery disease [CAD]: 54%; candidacy for implantation of a cardioverter defibrillator [ICD]: 10%. Follow-up: 104 patients could be evaluated; In 101 patients [97%] the follow-up was complete until census. Mean follow-up of the survivors was 1.23 y [max. 2.48 y.]. Endpoints: 15 deaths, after 0.81 y [range 3d-1.99 y]; 2 hard events. Normal perfusion was seen in 11 patients, reversible defects in 23 and irreversible defects in 70. Cox regression analysis showed prognostic value for survival: any defect in apical and/or inferolateral region (relative risk [RR] 1.92 and 1.5 resp.). Contributing clinical parameters in univariate analysis for survival were age [1.11, P<0.02] and MI [RR 2.01, P<0.05], and for hard event-free survival: age [RR 1.12, P<0.005]; established CAD [RR 3.40, P<0.01] and ICD-candidacy [RR 11.03, P<0.01]. Stepwise analysis, with clinical data in block 1 and perfusion and function (wall motion and thickening, left ventricular [LV] ejection fraction and LV volumes) data in block 2 for hard event-free survival: (block 1) age [RR 1.12, P<0.0005, CI 1.05-1.19]; established CAD [RR 2.98, P=0.003, CI 1.70-4.90] and ICD [RR 18.52, P=0.001, CI 3.23-100]. Chi-square block 1: 23.2, P<0.00005. Block 2, no perfusion or function data, nor any derived summary statistic contributed the model. Apart from block 1 (only age was predictive [RR 1.12, P=0.002, CI 1.041.20]), similar results were obtained for survival. Conclusions: Gated SPECT has prognostic value in patients with left bundle branch block. However, when clinical data is taken into account in this group, gated SPECT has no incremental prognostic value.

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Coronary Angiography Decision in Patients with Normal Thallium201 Myocardial Perfusion SPECT M. Unlu (1), N.H. Temiz (1), E. Cingi (1), T. Atasever (1), A. Çengel (2). (1) Department of Nuclear medicine of the Gazi University Faculty of medicine, Ankara, Turkey, (2) Department of cardiology of the Gazi University Faculty Of medicine, Ankara, Turkey. The aim of the study was to analyse predictive factors effecting on Coronary Angiography (CA) decision in suspicious coronary artery disease (CAD) pts, altough they had normal Thallium-201 myocardial perfusion SPECT (nMPS). A total of 874 pts (420 women, 454 men, mean age:50±5.3) who had normal treadmill exercise/ rest MPS followed up for three months. According to Framingham risk scoring scale short term risks of CAD were evaluated. During follow-up 186 pts (21%) with a very low risk scan underwent CA. In the study cohort and in pts who had CA, frequency of various determinative factors were as follows respectively; angina symptoms: 25%-54%, positive exercise electrocardiography (EECG): 17%-65%, having ≥10% risk score 58%-75% and having ≥20% risk score 12%-42%. In CA only 9 of the 186 pts showed significant CAD. (≥50% stenosis) Seven of these pts had single vessel and two had two vessel disease (RCA+LCx, LAD+LCx) and none of the lesion revealed ≥70% stenosis. Considering the pts who underwent CA, negative predictive value of nMPS was 95%. In this population positive EECG findings and having ≥10% risk score were two effective predictors of CA decision. However, only in 5% of these pts CAD was detected. None of the patients in the study group developed any cardiac event during follow-up period. As a conclusion, in pts with suspicious CAD, normal or low risk Tl-201 MPS with the best negative predictive value when compared to other determinants is more reliable in decision making of CA and excluding CAD.

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Tetrofosmin perfusion scintigraphy has considerable incremental prognostic value in symptomatic patients with coronary artery disease J.J.J. Borm (1), Y.G.C.J. America (1), C.S.J. Duchateau (1), E.E. van der Wall (2), E.K.J. Pauwels (1). (1) Department of Radiology Division of Nuclear Medicine, Leiden University Medical Center, (2) Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands. Aim: To asses the incremental prognostic value of tetrofosmin myocardial perfusion scintigraphy [MPS] in symptomatic patients with coronary artery disease [CAD]. Methods: Follow-up study in consecutive patients undergoing routine MPS. Inclusion criteria: Symptomatic patients with established CAD [previous revascularization, myocardial infarction [MI] or 50% stenosis on previous coronary angiography]. Cardioverter-defibrillator candidates were excluded. Recruitment from August 1995 until April 1998. Census date for follow-up was April 1st 1999. Analysis by means of Cox regression analysis. Endpoints: death; myocardial infarction, ECG-documented ventricular fibrillation; revascularization. Results: 602 out of 1269 patients were included. Patient characteristics: age 62 + 10 y; male 77%; average 2.44 riskfactors; previous infarction 56%, PTCA 34%, bypass surgery 36%, isolated angiographic abnormalities 4%. Follow-up: Average censored follow-up of survivors was 2.3 y [maximum 3.7 y]. Endpoints: 48 dead; 20 hard events; 122 revascularizations. The 48 non-survivors died after mean of 1.4 y [range 27 d - 3.6 y]. Normal perfusion in 122 subjects; reversible defects in 238 and irreversible defects in 242. Clinical risk factors in uni-variate analysis for survival:age [relative risk [RR] 1.06 per year]; diabetes [RR 2.8]; previous MI [RR 1.8/infarction]; previous PTCA [RR 0.61/PTCA]; left bundle branch block [LBBB] [RR 5.1]; diastolic blood pressure [RR 0.96/mmHg]. Stepwise survival analysis, with clinical data in block 1 and perfusion data added in block 2, found: (Block 1) LBBB [RR 4.9], Age [RR 1.058/y] and previous MI [RR 1.83/MI] [total chi-square 46.4, P < 0.00005] (Block 2) Defects [RR 1.3/segment], inferolateral segment [reversible: RR 0.34, irreversible RR 1.9], septal segment [reversible RR 1.8, irreversible RR 0.45] [change from block 1, chi-square 23.0, P 0.0003]. Total chi-square of the full model was 75.9 [P << 0.00005]. Similar results were obtained for hard-event-free survival. Using the full model 50% of the subjects was classified as at low risk, with similar 3 year survival as the age- and gender matched Dutch population. Using clinical data alone, only 25% of the subjects was classified as at low risk. Three-year survival of the 10% at highest risk was 61% for the full model, versus 67% for clinical data only. Conclusions: Tetrofosmin perfusion scintigraphy has considerable incremental prognostic value in symptomatic subjects with CAD.

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Tc-99-m Tetrofosmin SPECT on patients with acute chest pain in the emergency department. A. Micarelli (1), F. Scopinaro (2), G. De Vincentis (2), E. Ferranti (3), C. Danese (3), A. Serpietri (2), G. Di Iorio (1), S. De Matteis (1). (1) Hospital SS Annunziata, Sulmona-L’Aquila, Italy, (2) Depatment of Experimental Medicine-Section of Nuclear Medicine University of Rome La Sapienza, Rome Italy, (3) Department of Clinical Sciences Section of Nuclear Medicine University of Rome La Sapienza, Rome Italy. Aim. In patients with acute coronary syndrome ( ACS ) daily hospital cost is higher than myocardial SPECT. Purpose of present study is to confirm improvement of decision making with Tc-99-m Tetrofosmin SPECT (TSPECT) on patients with chest pain in emergency department. Materials and Methods. We enrolled 42 consecutive patients of Sulmona general hospital emergency department. Inclusion criteria were: first attack of anterior chest pain lasting more than 20’. Exclusion criteria were a) known ACS, stable angina, valvular heart disease, cardiomyopathy b) abnormal Q wave and evolving ST elevation higher than 1 mm, d) increased serum total CPK and CPK-MB. Patients arrived within 3 hours from onset of pain had ekg, echocardiography, serum troponine I measurement, rest TSPECT. Patients observed more than 3 hours after pain onset, patients without any ecg and serum signs of acute myocardial lesions had stress TSPECT too, with single day protocol. Patients with positive TSPECT findings were admitted to intensive care and selective angiography was performed, whereas patients with negative scan were followed up at home. Results. 10/42 ( 23,8% ) patients showed positive scan, 4 of whom at rest and six after exercise. 2/10 patients showed normal coronary arteries and 8/10 showed significant stenosis, three of the latter eight patients had ACS and received e.v. thrombolysis. 40/42 did not show segmental abnormal wall motion at echocardiographic examination. 7/10 patients with positive SPECT findings had normal ecg,, one patient had aspecific ecg abnormalities of ST tract and T wave and significant stenosis of DIA coronary artery, one patient showed left BBB and the last one ekg signs of ACS and positive angiography. 32/42 (76,2%) patients had negative rest and stress TSPECT were sent home; None of them showed new chest pain attack within 6 months. 23 out of these 32 patients had normal ekg., 9/32 patients with normal scan had abnormal ekg, 7 of them showed aspecific abnormalities of ST-T waves, 2/9 patients showed negative T wave. Discussion. Concordance of TSPECT with follow up was 38/42, with concordance likelihood of 90,5 %, whereas 4/42 might be false positive and negative, though with no recurrence of pain. The presumed true negative 28/42 patients significantly lowered costs for the hospital without any risk for them. Our study, performed on the general hospital of a small town, confirms the results of larger trials. Conclusion Myocardial TSPECT is cost-effective and fits well the needs of chest pain emergency departments

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Evaluation of left ventricle functions with 201 Tl myocardial Spect: Lung/Heart index in syndrome X patients. E. Entok (1), E. Vardareli (1), A. Birdane (2), Y. Cavusoglu (2), B. Timuralp (2). (1) Department of Nuclear Medicine,Osmangazi University Medical Faculty, Eskisehir, Turkey, (2) Department of Cardiology,Osmangazi University Medical Faculty, Eskisehir, Turkey. Increased lung uptake of 201Tl during exercise in Coronary Artery Disease (CAD) is evidence for left ventricle dysfunction. In SyndromeX patients impaired left ventricle function can be seen in exercise due to impaired coronary microcirculation. OBJECTIVES: In this study we aimed to observe the usage of increased 201Tl uptake in SyndromeX METHODS: our study group consisted 39 patients diagnosed syndromeX with normal Coronary Angiography (CAG) but ischemia findings in exercise test (ET) and exercise 201Tl myocardial SPECT and 11 patients with normal CAG,ET and exercise myocardial SPECT. SyndromeX patients seperated i 3 groups for the Ischemia Defects (ID)localization in 201Tl myocardial SPECT: GroupI, Left anterior descending artery (LAD), GroupII, Right coronary artery (RCA), GroupIII, both LAD and RCA region ID. Drawing the ROI’s around heart and right lung Lung/Heart (L/H) ratio calculated from 201Tl myocardial SPECT images.The ratios obtained from the groups compared with the L/H ratio of normal patients. RESULTS: The rest ratios were 0.46+0.11 in groupI,0.43+0.1 in groupII, 0.41+0.12 in groupIII and 0.40+0.03 in normal groups (p>0,05). Exercise L/H ratios 0.47+0.21 in groupI, 0.44+0.1 in groupII, 0.49+0.03 in groupIII and 0.32+0.01 in normal groups. Significant difference observed in normal groups (p<0.001, p<0.001,p<0.001). But there wasn’t any difference of exercise L/H ratios between groupI,II and III. CONCLUSION: As aresult in syndromeX although coronary arteries may appear normal, left ventricle function may be impaired in exercise. Between localization of ID and left ventricle dysfunction has not been found correlation. L/H indexi thought to be an important parameter increasing myocardial SPECT clinical value

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The evaluation of Myocardial Perfusion SPECT in patients with coronary artery disease and effects of dobutamine on the dynamics of late potentials E. Entok (1), O. Goktekin (2), M. Melek (2), E. Vardareli (1). (1) Department of Nuclear Medicine,Osmangazi University Medical Faculty, Eskisehir, Turkey, (2) Department of Cardiology,Osmangazi University Medical Faculty, Eskisehir, Turkey. Aim: Dobutamine myocardial perfusion SPECT (MP SPECT) is a useful method for detecting coronary artery disease (CAD). Presence of late potentials (LP) is thought to serve as a stable arrhythmia substrate in patients after myocardial infarction (MI).The goal of our study was elucidation whether development of ischemia during dobutamine stress test, documented by MP SPECT may affect LP parameters. Method: The study consisted of 14 patients with suspected of CAD and referred for MP SPECT. MP SPECT was applied with Tc-99m-MIBI by single day rest- dobutamine stress protocol. All patients underwent signal-averaged ECG at rest and at the maximal heart rate during dobutamine infusion. The following parameters entered the statistical analysis: filtered QRS duration (HFQRS), duration of the low amplitude signal below 40uV at the terminal QRS portion (LAS40), voltage in the last 40 ms of the filtered QRS complex (RMS40) at rest and during maximal stress. Results: Five patients had signs of necrosis, among them 3 had additional ischemia on dobutamine MP SPECT and 9 patients developed ischemia without necrosis. Ventricular arrhythmias were observed at peak stress in six patients. There was a significant prolongation of LAS 40 (40.2+5.4 ms vs 46.5+10.2 ms, p<0.05) and reduction in RMS 40 (18.0+8.6 uV vs. 13.4+5.0 uV, p<0.03) at the peak of dobutamine infusion. While no significant differences were noted in filtered QRS duration. Conclusion: Thus, late potentials showed an evident dynamics during DMPS in patients with CAD with prolongation of LAS40 and reduction of RMS 40. These findings testify that LP may exhibit dynamic changes possibly due to the development of ischemia in this category of patients

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Quantitative evaluation of Myocardial Perfusion SPECT in patients with coronary artery disease and impact of ischemia or necrosis on heart rate variability and QT dispersion

Tetrofosmin had similar sensitivities for the detection of perfusion defects in patients with multivessel coronary disease, as well as for the detection of the “guilty” vessel in comparison with coronary angiography.

E. Emre (1.), O. Goktekin (2.), M. Melek (2.), E. Vardareli (1.). (1) Department of Nuclear Medicine of the Osmangazi University, Eskisehir, Turkey, (2) Department of Cardiology of the Osmangazi University, Eskisehir, Turkey. Background: It has been supposed that there is relationship of QT interval dispersion (QTD) with ischmeia in patients with coronary artery disease (CAD). Although differences in QTD during dobutamine stress (DS) induced ischemia with or without necrosis has not been exactly quantified in CAD. Aim: This aim of study was to determine the effect of ischemia with or without necrosis induced by DS on QTD and heart rate variability (HRV) Method: Twenty-five patients with known CAD and 10 controls underwent DS with MPS entered the study. MPS was performed with Tc-99m MIBI by single day rest- dobutamine stress protocol. MP SPECT images were divided into 20 segments and regional Tc99m MIBI uptake were quantitatively analyzed. For quantitative analysis of the SPECT data, a four-point scoring system was used in each myocardial segment. Short-term ECG recordings were performed at rest at peak DST with further post-processing spectral analysis of HRV and assessment of the following parameters: very-low (VLF), low (LF), high (HF) frequency powers, total power (TP) and LF/HF ratio. Maximal and minimal values of QT interval with further calculation of QT dispersion (QTD) were measured from the obtained 12-lead ECGs at rest and at peak DST. Statistical without underlying necrosis was accomplished using MannWhitney nonparametric test. Result: In 17 patients with CAD, ischemia was documented by quantitative MPS (Group 1 ) and 8 Pts had signs of necrosis (group II) on quantitative MPS. There were no differences between patients and control groups. Comparison of QTD at peak DST between groups showed that QTD was significantly higher in both groups of patients with CAD(48.2+32.6 ms and 54.2 +24.3 ms vs. 29.0+15.1 ms, group I vs.control – p<0.02 and group II vs. control p<0.04) as compared with controls. QTD values did not differ at peak DST between those with ischemia and necrosis. Analysis of HRV changes during peak DS revealed its marked reduction in all patients and control groups. However, comparison of HRV changes at the peak of DS between patients groups and control one showed more pronounced reduction of spectral powers. (Log VLF 0.86+0.22 vs. 1.49+0.60 and 1.55+0.77, p<0.01 and p<0.02, Log LF –0.07+0.2 vs 0.75+0.76 and 0.73+0.86, p<0.01 and p<0.02, Log HF –0.11+0.26 vs. 0.40+0.62 and 0.47+0.74, Log TP0.96+0.17 vs. 1.63+0.5 and 1.68+0.7, p<0.01 and p<0.01) in Group II than in Group I and controls. There were no diffrences in HRV between Group I and controls at peak stress test. Conclusion: This study suggestes that patients with necrosis on MPS had the similar enhancement of QT dispersion as those with the development of ischemia, while had significantly higher attenuation of HRV (autonomic burden) at the peak of dobutamine stress test.

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Comparative study between SPECT with Tl-201 and Tc99mTetrofosmin in multivessel coronary disease and their correlation with coronary angiography

Tc-99m Sestamibi Myocardial Perfusion Scintigraphy for Sypmtomatic and Asymptomatic Coronary Artery Disease in Diabetic Patients

J.P. Suárez (1), C. Roiz (1), M.L. Domínguez (1), N. Zeidán (1), L. Bernardo (1), B. Llana (1), R. Núñez (2), J.L. Negrete (3), A. Alvarez (1). (1) Department of Nuclear Medicine of the Hospital Central de Asturias, Oviedo, Spain, (2) Division of Nuclear Medicine of the Long Island Jewish Medical Center, New York, USA, (3) Department of Cardiology of the Hospital Central de Asturias, Oviedo, Spain.

O. Omur (1), A. Dirlik (1), E. Acar (1), Z. Danalioglu (2), M. Argon (1), Z. Ozcan (1). (1) Department of Nuclear Medicine of Ege Univercity Medical Faculty, (2) Department of Cardiology of Ege Univercity Medical Faculty. Izmir, Turkey.

OBJECTIVES: The aim of this study was to compare the sensitivity of myocardial perfusion SPECT with two different tracers (Tl201 and Tc99m-Tetrofosmin) for the detection of perfusion defects (fixed or reversible), and detection of the “guilty” vessel (the most affected vessel) in patients with multivessel coronary disease. MATERIAL AND METHODS: The study was performed in 78 patients (68 males and 20 females), with a mean age of 62 years (age range 37-79 years) with multivessel coronary disease diagnosed by coronary angiography. 8 patients presented with left bundle branch block (LBBB) and 36 had a history of prior acute myocardial infarction (AMI). 36 patiens were studied with 130 MBq of TL201 using a stress/redistribution SPECT protocol, follow by reinjection at rest of 37 MBq of Tl201 and SPECT imaging, after pretreatment with nitroglycerin. The other 42 patients had a stress and a rest myocardial perfusion SPECT performed on two consecutive days, after the administration of 740 MBq of Tc99m-Tetrofosmin (Myoview, Amersham Health), on each day. SPECT images were acquired using an Elscint SP4 tomogammacamera (Haifa, Israel). The extent of necrotic and isquemic areas was assessed with bull-eye quantification, in order to determine the percent of each coronary artery territory affected (left anterior descending coronary artery, LADCA; right coronary artery, RCA; and circumflex coronary artery, CCA), and evaluate the uptake ratio considered as pathologic. These results were compared with the ones from coronary angiography. RESULTS: Fixed and reversible perfusion defects were detected in 35 of 36 patients (97%) studied with Tl201 of whom, 22 (62.8%) had suffered AMI. The patient with a normal myocardial perfusion, had 2 affected territories (RCA and CCA) and had suffered AMI. In addition, the “guilty” vessel was not detected in 2 patients, who had similar stenosis in all three coronary artery territories. Perfusion defects were detected in 40 of 42 patients (95%) studied with Tc99m-Tetrofosmin, 19 of whom (47.5%) presented LBBB and/or AMI. One of the two patients with normal myocardial perfusion had similar stenosis in all three coronary artery territories. In comparison with coronary angiography Tl201 SPECT detected the “guilty” vessel in 74% of the patients, with a sensitivity for each territory of: 71%- LADCA , 73%- RCA and 67%-CCA. Tc99m-Tetrofosmin detected the “guilty” vessel in 72% of the patients, with a sensitivity for each territory of: 75%- LADCA, 82%-RCA and 60%-CCA. CONCLUSIONS: In this study, myocardial perfusion SPECT with Tl201 and Tc99m-

Aim: The increased for coronary artery disease (CAD) associated with diabetes mellitus is well-known. The aim of this study is to investigate the value of Tc-99m MIBI myocardial perfusion scintigraphy (MPS) in the assessment of CAD in patients with diabetes mellitus (DM). Methods: 50 type II DM and 35 non-DM patients were included in study population. Mean duration of diabetic disease was 7.4±64 years. All patients were studied with stress-rest Tc99m MIBI MPS protocol. MPS findings were correlated with clinical findings, stress ECG, ECHO and angiography. MPS data were examined by semiquantitative and visual analysis. Myocardial perfusion was scored using a colour scale. Perfusion defect is defined when uptake is < 70 % of normal perfusion. Extent of involvement was estimated by using defect score (DS) after constructing 20 myocardial segments. The perfusion of each segment was classified as normal, fixed (FDS) or reversible defect (RDS). Results: Abnormal myocardial perfusion pattern was found in 24 of 50 (48 %) diabetic patients. Eleven of these 19 patients had no history of cardiac event and symptoms. Five of them found to have silent myocardial ischemia and silent myocardial infarction (MI) in four diabetic cases. Mean DS, RDS and FDS were 6.13, 3.88, 2.25 respectively. When these results were compared with those of non-diabetics, mean DS, RDS and FDS were 4.77, 2.85, 2.00 respectively (p>0.05). Multivessel disease pattern was more frequent in diabetics (45.8 % vs 15.3 %, p<0.05) than non-diabetic cases. Myocardial perfusion abnormality was significantly related with duration of diabetes and systemic complications such as nephropathy and polyneuropathy. Conclusion: The frequency of abnormal myocardial perfusion and silent cardiac events led us to suggest that MPS should be used in the evaluation of asymptomatic high-risk diabetic patients.

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D.Y. Kang (1), K.S. Cha (2), M.H. Kim (2), Y.D. Kim (2), D.K. Kim (1). (1) Department of Nuclear Medicine of Dong-A University Hospital, Busan, Korea, (2) Department of Internal Medicine of Dong-A University Hospital, Busan, Korea.

C.T. Mesquita (1,2,3), M.C.P. Pessoa (2), E. Perin (4), A. Sousa (1,4), N.D. Mattos (1), F.O.D. Rangel (1), A.G. Reis (3), H.F.R. Dohmman (1), L.M.B. Fonseca (2). (1) Hospital Procardiaco, (2) Universidade Federal do Rio de Janeiro, (3) Hospital São Lucas, (4) Texas Heart Institute, Rio de Janeiro, Brazil and Houston, USA.

Myocardial hypoperfusion and location of accessory pathway in patients with WPW syndrome

Aim: Myocardial perfusion is altered significantly in patients with rhythm disturbances such as LBBB and right ventricular pacing rhythm. Abnormal myocardial perfusion may be caused by ventricular pre-excitation, but its location, extent, severity and correlation with accessory pathway (AP) are not established. We evaluated perfusion patterns on SPECT and location of AP in patients with WPW syndrome. Materials and Methods: Adenosine Tc-99m MIBI or Tl-201 myocardial perfusion SPECT was performed in 11 patients with WPW syndrome. Perfusion defects (PD) were compared to AP location based on ECG with Fitzpatrick’s algorithm or electrophysiologic study and radiofrequency catheter ablation. Results: Mean age was 38±8.6 yrs (28?66). Patients had no symptoms or atypical chest discomfort. Coronary angiography was performed in 4 patients (mid-LAD 50% in one, normal in others). In 4 patients, AP localization was done by electrophysiologic study and radiofrequency catheter ablation (RFCA). Small to large extent (11.0±8.5%, range:3?35%) and mild to moderate severity (-71±42.7%, range:-217?-39%) of reversible (n=9) or fixed (n=1) perfusion defects were noted. One patient with right free wall (right lateral) AP showed normal. PD locations were as follows: (1) apex, anteroinferior, inferior, inferolateral in 2 patients with right free wall (posterolateral) AP (2) inferior, apex, anteroinferior, septal in 3 patients with posteroseptal wall AP (3) inferior, anterolateral in 1 patient with left posterior wall AP (4) lateral, apex, inferior, inferolateral in 4 patients with left lateral wall AP. One patient with left lateral wall AP was followed 6 weeks after RFCA and showed significantly decreased PD on SPECT with successful ablation. Conclusion: Myocardial perfusion defect showed variable extent, severity and location in patients with WPW syndrome. Abnormal perfusion defect showed in most of all patients, but it did not seem to be correlated specifically with location of accessory pathway. Therefore myocardial perfusion SPECT should be interpreted carefully in patients with WPW syndrome. And myocardial perfusion SPECT may be useful to evaluate the efficacy of RFCA.

Evaluation of Myocardial Stress Perfusion Imaging after Stem Cell Therapy in Patients with Advanced Left Ventricular Dysfunction

Aim: The purpose of this study was to evaluate the behavior of myocardial stress perfusion after local implantation of stem cells in patients with advanced left ventricular dysfunction assigned to the heart transplantation waiting list. Material and Methods: 4 patients with advanced ischemic heart failure not suitable to any revascularization procedure were submitted to intra-myocardial autologous stem cell infusion in areas of reversible perfusion defects. We compared dypiridamole stress technetium-99m sestamibi SPECT imaging carried out before stem cell therapy to a new study obtained 2 months after therapy. Results: One patient had no change in the post-treatment dypiridamole stress technetium-99m sestamibi SPECT compared to the SPECT images done before stem cell treatment. One patient demonstrated moderated reduction of the ischemic area. One patient showed reverse reperfusion in a previously ischemic area and the last patient showed a reverse reperfusion pattern associated to a reduction of ischemic area. Conclusion: In this small series of patients submitted to stem cell therapy we noted changes in the myocardial stress perfusion pattern 2 months after the treatment. The development of reverse reperfusion and reduction of ischemic areas suggest that a beneficial effect may be associated to this therapy. Longer follow-up and more patients studied are necessary to draw definitive conclusions about the role of this new therapy.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition DIAGNOSTIC ONCOLOGY

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Efficacy of the direct myocardial revascularization performed on the beating heart and performed with the use of extracorporal circulation - comparison by the means of myocardial perfusion SPECT

Radiopharmaceuticals to monitor the response to therapy: in vitro screening of F-18-DG, Tc-99m-Tetrofosmin, I-125-MT and I-125UdR.

R. Czepczynski (1), P. Kwinecki (2), M. Jemielity (2), M. Baczyk (1), W. Dyszkiewicz (2), J. Sowinski (1). (1) Department of Nuclear Medicine of the University School of Medical Sciences, Poznan, Poland, (2) Department of Cardiac Surgery of the University School of Medical Sciences, Poznan, Poland.

L.F. de Geus-Oei (1), J.E.M. van Eerd (1), C.F. Molthoff (2), W.J.G. Oyen (1), F.H.M. Corstens (1), O.C. Boerman (1). (1) University Medical Center St.Radboud, Nijmegen, Netherlands, (2) University Hospital Vrije Universiteit, Amsterdam, Netherlands.

Introduction. In the recent years, new techniques of direct myocardial revascularization: OPCAB – off pump coronary artery bypass and MIDCAB – minimal invasive coronary artery bypass were developed. Aim of this study was to compare the efficacy of these methods with that of CABG performed with the use of extracorporal circulation. Material and methods. 20 patients operated on the beating heart (group 1; 16 men and 4 women; aged 40 to 65 years; mean 53,0 ± 8,6 years) and 36 patients operated in the extracorporal circulation (group 2; 33 men and 3 women; aged 34 to 69 years, mean 52,5 ± 8,6 years). In all the patients myocardial SPECT using 99mTc-MIBI at rest and after stimulation with dipyridamole (0,56 mg/kg) was performed twice: before and 4 – 7 months after revascularization. Myocardial perfusion was evaluated in 9 segments using following scale: from 1 (normal) to 5 points (no uptake). The average score in all nine segments constituted a perfusion index (PI). The differences of PI before and after operation, both at rest and after dipyridamole were compared. Results. In none of the patients of group 1 a perioperational ischemia was found by ECG or enzymatic (CK-MB) measurements. In a part of group 2 signs of transient ischemia were found. Global evaluation of perfusion in SPECT is presented in the table: Group 1 Group 2 DPI – rest 3,68 ± 3,72 2,76 ± 2,97 DPI – dipyridamole 7,95 ± 6,25 5,82 ± 5,40 DPI were similar in both groups, both at rest and after dipyridamole.

p ns ns

Wniosek. Efficacy of the direct myocardial revascularization performed on the beating heart is similar to that of the CABG operations performed with the use of extracorporal circulation. The OPCAB and MIDCAM operations are less traumatizing.

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Objectives: It has been postulated that various radiopharmaceuticals could be used to predict the therapeutic response to (chemo)therapy, which could lead to individualized treatments. In this study 4 radiopharmaceuticals (18F-deoxyglucose (= FDG), 99mTc-tetrofosmin (= TF), 125Ideoxyuridineribose (= IUdR) and 125I-methyltyrosine (= IMT)) were tested for their ability to predict the response of cancer cells to doxorubicine (= Dox) treatment. Methods: The uterine sarcoma cell line MES-SA and its multiple drug resistent (MDR) variant, MES-SA/Dx5 were used. In contrast to wild-type MES-SA cells (MDR-), the MES-SADx5 cells (MDR+) express high levels of MDR-1 RNA and P-glycoprotein (Pgp). As a result the cells are relatively resistent to Dox as well as to various other chemotherapeutic agents. Cells were cultured in 6-wells plates in the presence of escalating concentrations of Dox (0 1000 µM) and in the presence or absence of Verapamil (5 µg/well) during 48-72 h. During the last hour the radiopharmaceuticals were added (106 cpm/well). After washing the cells were counted in a well-type gamma counter. Results: Baseline FDG of the MDR- cells was 2-fold higher than of MDR+ cells, reflecting the enhanced proliferation rate of MDR- cells. The FDG uptake at escalating Dox doses reflected the chemo-sensitivity of the cells: FDG uptake of the MDR- cells was 600-fold lower at 10 µM Dox, whereas the FDG uptake in MDR+ cells decreased only 4-fold. The IUdR uptake in MDR- cells decreased 300-fold when cultured in 1 µM Dox, while the reduction of IUdR of MDR+ cells was less than 2-fold. The same trend, although less apparent, was observed with IMT: IMT uptake decreased 9-fold in MDR- cells, whereas no reduction was observed in MDR+ cells when cultured at 1 µM. Baseline TF uptake of the MDR+ cells was more than 12-fold lower than of MDR- cells, due to enhanced Pgp activity of MDR+ cells. In the presence of Verapamil, uptake patterns of the 4 radiopharmaceuticals in both cell lines became almost similar. Conclusion: FDG, IUdR and IMT uptake is more pronouncedly reduced in MES-SA cells that respond to exposure to Dox than in cells that do not. IUdR displayed the most marked relative reduction. Unlike these three radiopharmaceuticals, TF shows these differences before exposure to Dox, reflecting the expression of the MDR-1 gene. The Pgp modulator Verapamil is able to reverse the Dox resistance. A nude mice tumor model has been developed to study this phenomenon in vivo.

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n DIAGNOSTIC ONCOLOGY Objective evaluation and staging of the therapeutic response to In111 Octreotide - based therapy in Liver Neoplasms G.S. Limouris, N. Dimitropoulos, I. Athanassiadis, D. Skarlos, A.P. Frantzis, A. Hatziioannou, V.K. Koutoulidis, D. Mourikis, A. Stavraka. Radiology Dept, Nuclear Medicine Div, Areteion Univ Hosp, Athens, Greece. Introduction: In hepatocellular carcinomas except surgical resection (treatment of choice) chemo-embolization, cryotherapy, radiofrequency ablation, chemo- and biological therapies (tamoxifen, interferon, sandostatin) are still of no proven clinical benefit, whereas in metastatic tumors the aforementioned schemes claim objective response; however they rarely offer a curative potential. Recently in routine basis, usually in combination to the above referred therapies, In-111 Octreotide, Y-90 / In-111 and Lu-177 DOTA conjugated peptides are applied as a new alternative therapeutic option. Purpose: To evaluate the alterations of the lesions during the therapeutic sessions and to patternalize the degenerative procedure according to the absorbed dose. Material and Methods: In-111 Octreotide infusions, via intrahepatic catheterization started in August 1997 and routinely continues up to day. Since that time 13 patients were treated, 4 with hepatocellular carcinoma and 9 with neuroendocrine tumors. Long term and thorough follow up continues up to now. Evaluation of the therapeutic procedure was focused on ultrasonography, since it is preferable for closer correlation of the degenerative procedure , shown after each catheterization, for better evaluation of the size and the degree of cystic degeneration of each individual hepatic lesion. CT and / or MRI scans of the liver were performed at the beginning, the middle and the end of the therapies for evaluation the overall parenchyma consistency and numbers of the lesions. Results: Stage I ( 1st to 3rd catheterization) ( early signs of regression as an echolucent rim in the periphery of the malignant lesion, sometimes accompanied by rim cystic degeneration; Stage II ( 4th to 7th catheterization) ( appearance of two types of cystic degeneration: (a) the Swiss-cheese type (where the solid nodule becomes full of tiny cystic spaces) and (b) the cavity type (where a dominant cystic area appears in the periphery of the lesion and expands to the nodule center. In 4 cases both types of cystic transformation appear simultaneously and in 9 the first type was followed by the second whereas in the same nodule; Stage III ( 8th catheterization a.s.o)( in 5 out of 13 patients the produced cystic component was absorbed and totally disappeared while in 8 of 13 small or cystic-granulomatous remnants remained stable in consecutive exams. Conclusion: The evaluation and patternalization of changes of the hepatic lesions after appositive response to In-111 Octreotide based-targeted-therapy using ultrasonography, CT or MRI objectively proved the curative rather than palliative effect of Auger and Conversion Electron treatment of these life threatening diseases. Ultrasonography appears to be the imaging procedure of choice because the examination is cheap, easy to perform, without additional radiation, very sensitive in evaluating lesions’ oedema, the cystic component and precise measurement of the tumor size.

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Preoperative Parathyroid Localization with 99mTc-Sestamibi and Minimally Invasive Parathyroidectomy with Gamma Probe R. Bekis (1), K. Atila (2), M.A. Kocdor (2), A. Aydin (1), A. Sevinc (2), S. Saydam (2), Ö. Harmancioglu (2), H. Durak (1). (1) Department of Nuclear Medicine of the Dokuz Eylul University of Izmir, Izmir, Turkey, (2) Department of Surgery of the Dokuz Eylul University of Izmir, Izmir, Turkey. Aim: The inability to predict the location and number of diseased parathyroid glands has precluded the wide acceptance of unilateral neck exploration for primary hyperparathyroidism. We used intraoperative nuclear mapping in patients identified by sestamibi scanning to have a single adenoma in hoping to minimize operative intervention while maintaining the efficacy of a full exploration. Method: Eight consecutive female patients (46-72 years, mean age 59) with the biochemical evidence of primary hyperparathyroidism in whom a high quality 99mTc-sestamibi scan and utrasonography demonstrated a single adenoma were included to the study. Minimally invasive unilateral neck exploration with gamma detector-guided parathyroid surgery was performed to the patients in this prospective study. 740MBq of 99mTc-sestamibi was intravenously administered to each patient 3 hours before operation. Placement of the initial 2.0 cm incision and all dissection were guided by quantitative gamma counting in four neck quadrants with an gamma probe (Neoprobe 2000) under general anesthesia. Ex vivo radioactivity was determined for parathyroid glands, fat, and lymph nodes. Lesion/Background were calculated. Results of the radionuclide studies were compared with surgical and frozen section findings. Results: All patients had solitary adenomas that were localized preoperatively by the scan and frozen section. Average total operative time was 41 minutes. Patients were cured after operation. There were no complications. Parathyroid adenoma is confirmed histopathologically in all excised tissues. Conclusion: Incidence of multiple adenomas in primary hyperparathyroidism was reported to be 6 % in literature. In the majority of the patients (94 %), parathyroid localization with sestamibi is an effective preoperative method. This technique may allow for a minimally invasive operation under local anesthesia in a true outpatient setting and may decrease morbidity of full exploration.

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Effect of Thyroid Dysfunction on Concentration of Vascular Endothelial Growth Factor in the Blood of Patients with Differentiated Thyroid Carcinoma T. Traub-Weidinger (1), U. Resch (1), F. Girschele (1), P. Schaffrich (1), C. Poetzi (1), A. Krcal (1), I. Virgolini (2,3), R. Dudczak (1,3), S. Li (1). (1) Department of Nuclear Medicine, University of Vienna, Vienna, Austria, (2) Institute of Nuclear Medicine, Vienna Hospital Lainz, Vienna, (3) Ludwig Boltzmann Institute of Nuclear Medicine, Austria. Aim: Vascular endothelial growth factor (VEGF) has been identified as a potent angiogenic factor in many tumors including human thyroid carcinoma. Recently, increasing data have shown that high level of VEGF concentration in patients with malignance may be predictor for tumor metastasis and prognosis. Based on the assumption that thyroid dysfunction may influence the VEGF levels in blood, we determined the VEGF concentration both in plasma and serum from patients with differentiated thyroid carcinoma in hyperthyroid and hypothyroid states. Materials and Methods: The plasma and serum concentration of VEGF and thyroid function parameters (free thyroxine (fT4), free triiodothyronine (fT3) and thyroid stimulating hormone (TSH)) were determined in 18 patients with differentiated thyroid carcinomas in hypothyroid and hyperthyroid states. Routine evaluation included peripheral blood cell counts, thyroglobulin and thyroid immunoglobin. Results: The plasma VEGF levels was significantly (p<0.05) elevated in the hypothyroid state compared to that in the hyperthyroid state. There is a significant positive correlation between plasma VEGF levels and TSH. However, the concentration of serum VEGF was not significantly different in the hyperthyroid state and hypothyroid state. The concentration of VEGF in serum was significantly higher than that in plasma in all subjects. The major part of vascular endothelial growth factor derives from in vitro degranulation of granulocytes and platelets in serum. Therefore, plasma may be preferred for vascular endothelial growth factor measurements. No significant positive correlation was observed between the blood VEGF levels and thyroid immunoglobin concentrations. Conclusion: We conclude that the thyroid dysfunction may cause significant alterations in the blood concentrations of VEGF in patients with differentiated thyroid carcinomas. This results may have important implications for clinical treatment of these patients.

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A reassessment of bone scintigraphy and commonly tested pretreatment biochemical parameters in newly diagnosed osteosarcoma M.P.M. Stokkel, J.J.J. Borm, E.K.J. Pauwels. Department of Nuclear Medicine of the Leiden University Medical Centre, Leiden, The Netherlands. Aim: In patients with an osteosarcoma, the prognosis and survival are is still very poor. The aim of the present study was to investigate whether routinely tested biochemical parameters or additional parameters on bone scintigraphy could be identified which can select prognostic subgroups at the time of diagnosis. Materials and methods: A retrospective study was performed in 115 consecutive patients (70 male, 45 female) (mean age: 25,6 yrs; range: 3.50 – 78.0 yrs) who were referred for bone scintigraphy prior to treatment from March 1986 to September 2000 because of a newly diagnosed osteosarcoma. All bone scans were reassessed for the intensity and pattern of uptake at the site of the primary tumour as well as for a bone scan index. Furthermore, the presence and number of metastases was scored on bone scintigraphy. All pre-treatment general, histological, biochemical and scintigraphic data were correlated with tumour recurrence and/or progression during follow-up as well as with survival. Results: During follow-up 54 patients died, whereas in 67 patients metastases were seen. The maximum interval between initial diagnosis and the presentation of these metastases was 5.3 years. In 7% of the patients, bone was the only site metastatic disease at initial stage. During follow-up, the lung was the presenting site of recurrence. Tumour volume and GGT showed significance as independent variable for metastases. Patients with metastases demonstrated a significantly lower survival rate (23% 5-year survival) than patients without metastases (98% 5-year survival). Tumours of the humerus and femur had a significantly lower survival rate. With respect to significant biochemical parameters (ALP, GGT, ASAT), it was not possible to determine a cut-off value that could be used to differentiate between high and low risk patients. Additional parameters assessed on bone scintigraphy were not important for prognostic stratification. Conclusion: The strongest predictor of survival in osteosarcoma is the presence or absence of metastasis. Consequently, both CT-scanning and bone scintigraphy should be performed at initial stage. CT-scanning of the chest is the first test of choice to assess tumour recurrence as the lungs are the presenting site of metastases during follow-up. Some biochemical parameters have prognostic value, but they can not be used for the unequivocal identification of subgroups. Additional scintigraphic parameters, such as intensity or pattern of uptake, are irrelevant for prognostic stratification.

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Efficacy of Tc99m Neotect study in evaluation of pulmonary nodules S. Dadparvar (1), J.Q. Yu (1), R.K. Grewal (1), T. Cavanaugh (2), C. Babaria (1), V.K. Reddy (1), J. Jacobstein (2). (1) Department of Nuclear Medicine, Hahnemann University Hospital, Philadelphia, PA USA, (2) Department of Radiology, Graduate Hospital, Philadelphia, PA USA. Purpose: Neotect (Depreotide) is a peptide of somatostatin receptor analog which specially binds to somatostatin receptors 2,3 and 5. Many lung tumors may express these receptors more than normal tissue. Tc99m Neotect study is a noninvasive, receptor specific imaging agent which is used to assess malignant vs. benign single pulmonary nodules prior to biopsy. Materials and Methods: Thirty-nine patients (15 males, 24 females), with mean age 56.6 years (range 39-86) underwent forty-two studies. The SPECT of the chest and whole body imaging were performed 2 hours following intravenous injection average dose of 24 mCi 99mTc Neotect (Depreotide). The Region of Interest was drawn around each lesion and tumor to background ratio was measured. The images were classified as true positive when the tumor uptake and histopathology were concordant. The studies were classified as true negative when there was no uptake and no malignancy seen in pathological correlation. The studies were classified as false positive when there was uptake in areas other than tumor and false negative when no uptake in the tumor was identified. The CT and pathological correlation were performed. Results: The comparison of CT vs. Tc-99m Neotect study revealed sensitivity of 1.0 vs. 0.9 (p=ns), Specificity 0.43 vs. 0.19 (p=0.05), Accuracy 0.71 vs. 0.55 (p=ns), Positive predictive value 0.64 vs. 0.53 (p=ns) and Negative predictive value 1.0 vs. 0.67 (p=0.03). The tumor to background ratio ranged from 1.15 to 3.77. . There was no relationship between the histology and tumor uptake ratio. The tumor uptake was high in acute and active inflammation. Conclusion: Tc-99m Neotect is a sensitive imaging modality with better specificity and negative predictive value when compared to CT scan. There is no relationship between tumor uptake and differentiation of the tumor. We recommend this study in evaluation of single pulmonary nodules especially when PET scan is not available prior to biopsy.

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Possible significance of tumor marker (CA 15-3) assay level and bone pain presence in ordering a bone scan in the follow-up of the breast cancer patients S. Popadic (1), J. Vojicic (1), W.YU. Ussov (2), J. Mihailovic (1), G. Tomin (1), M. Malesevic (1), K. Kermeci (1), D. Srbovan (1). (1) Department of nuclear medicine,Institute of Oncology,Sremska Kamenica,Yugoslavia, (2) Tomsk Medical Research Center, Tomsk, Russia. Aim of the study: Follow-up of the patients with breast cancer in the routine practice of certain number of physicians includes both the bone scan and a tumor marker assay (CA 15-3) if the patient is complaining on the bone pain. In our study we tried to define whether a normal tumor marker level could be considered as a reliable predictor of a negative bone scan even in the patients (pts) with a pronounced bone pain. Material and methods: 294 female pts with breast cancer and performed tumor marker assay underwent a bone scan. Pts were divided into two groups – first one with normal and the second one with elevated tumor marker assay and two subgroups considering if they have had bone pain or not. Results were statistically analyzed with the chi-square test and rank correlation was also done. Results: We found normal tumor marker level in 228 pts (77%), while in 66 pts (23%) tumor marker level was elevated. In 189 (64%) of all patients we revealed normal bone scan, in 71 pts (24%) positive bone scan and in 34 pts (12%) doubtful bone scan finding. Obtained results showed that there is a high statistically significant relationship between tumor marker level and a bone scan result. No statistical significance was found in the correlation between the positive bone scan and the presence of bone pain. Conclusion: Our results suggested that a normal tumor marker (CA15-3) level in breast cancer patients is highly predictive of a normal bone scan, hence elevated tumor marker level is indicative of a positive bone scan finding. No significance considering the presence/absence of the bone pain could be explained due to the fact that bone pain is a highly subjective feeling, and various origins of the pain were displayed. breast cancer, tumor marker, bone scan,

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D. Casara, D. Rubello, S. Manente, R. Mazzarotto, G. Sotti. Radiotherapy and Nuclear Medicine Department, Hospital of Padova, Padova, Italy.

R. Bekis (1), B. Degirmenci (1), S. Sengiz (2), C. Tasci (1), E. Derebek (1), M.A. Kocdor (3), T. Canda (2), H. Durak (1). (1) Department of Nuclear Medicine of the Dokuz Eylul University of Izmir, Izmir, Turkey, (2) Department of Pathology of the Dokuz Eylul University of Izmir, Izmir, Turkey, (3) Department of Surgery of the Dokuz Eylul University of Izmir, Izmir, Turkey.

Microcarcinoma of the thyroid gland: natural history, therapeutic approach, and outcome in a group of 326 patients.

Microcarcinoma of the thyroid gland (MTG) is generally characterised by a favourable outcome. However, MTG can be an aggressive and even fatal tumour. Debate exists in literature about the ideal extension of primary surgery and subsequent follow-up. We report here our experience on diagnosis, treatment and outcome of MTG. The study is focused on a group of 326 patients with a thyroid cancer less than 10 mm in maximum diameter that is part of the total series of 3704 thyroid cancer patients (8.8%) treated in our centre over a 30-yr period: F=227, M=99; F/M=2.3; mean age 42.6 yrs, range 16-78 yrs; 293 papillary and 33 follicular. Preoperative diagnosis of cancer was obtained in 68 patients (20%) due to the evidence of cervical lymph node metastases LNM (n.=63), bone metastases BM (n.=3), and pulmonary metastases PM (n.=2) whereas in the other 258 patients (80%) the MTG was disclosed during an intervention for a benign thyroid disease (Grave’s disease = 16%, multinodular goitre = 75,5%, Hashimoto’s thyroiditis = 7.9%). All patients were treated by total thyroidectomy; 24 of them (7.3%) had previously undergone partial thyroidectomy and required re-operation of total thyroidectomy for recurrent disease in the thyroid remnants (n.=6) or loco-regional lymph nodes (n.=18). Then, in all cases a 131-I whole body scan (5 mCi) was obtained, and 218 patients (66.8%) received a therapeutic 131-I dose. The MTG size was 5.2+/-3.4 mm (range 2-10); the tumour was multifocal in 119 cases (36.5%), capsular invasions was found in 29 (8.9 %), and LNM in 158 (48.4%) (in 14 patients LNM were diagnosed only at 131-I scan). Moreover, 131-I scan showed BM in 4 cases and PM in 12 (in 7 of them chest x-rays was negative). During a follow-up of 14.3+/-8.7 yrs, local recurrences were observed in 14 patients (4.3%), (12 to lymph nodes and 2 to lymph nodes plus thyroid bed): all of them had LNM at first treatment, 3 had thyroid capsular invasion and 5 multifocal disease. The locoregional recurrence was successfully treated by 131-I in all these 14 patients. Tumour-related death was recorded in 2 patients: in both cases BM were present at first diagnosis. In conclusion, in our series we observed a relatively high prevalence of MTG with an aggressive pattern. It cannot be excluded that this is in part due to a close selection of patients referred to our centre. In spite of this, we believe that, whenever a total thyroidectomy is performed, it should be recommendable to obtain a diagnostic 131-I scan and to consider the potential benefit of 131-I treatment in cases with LNM, thyroid capsular invasion and multifocal disease.

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Correlation Between 99mTc-MIBI Uptake And Angiogenesis in Breast Lesions

AIM: This study was undertaken to assess the correlation between the degree of accumulation and washout of 99mTc-MIBI and angiogenesis in breast lesions. METHODS: Twenty-four patients (mean age 51±11) with 25 breast lesions (12 infiltrative ductal carcinoma, 4 infiltrative ductal and lobular carcinoma, 3 lobular carcinoma, 1 musinos carcinoma, 2 fibrocystic disease, 1 fibroadenoma, 1 mastitis, 1 radial scar) who underwent scintimammography were studied. Anterior, left and right prone lateral images were obtained 20 minutes and 3 hours after the injection of 740MBq 99mTc-MIBI. Early and delayed tumor to background activity ratios (T/BG) and washout index (early T/BG-late T/BG divided by early T/BG) were calculated. Vascular endothelium was labelled immunohistochemically using a biotinylated monoclonal antibody directed against the factor-VIII-associated antigen using standard biotin-avidin technique. Angiogenesis was evaluated within 10 randomly chosen areas for assessment of the vascular surface density (VSD), micro vessel number (NVES). All of the pathological data were compared with early and delayed T/BG activity ratios and washout index of 99mTc-MIBI. The statistical analyses was obtained by using Spearman correlation test. RESULTS: The 99mTc-MIBI scintimammography was true positive in 20, false positive in 5 lesions. There was a poor correlation between the degree of angiogenesis and 99mTc-MIBI uptakes, washout index in true positive and false positive groups (p>0.05). CONCLUSION: Amount of 99mTc-MIBI uptake in breast lesions is multifactorial. 99mTcMIBI uptake ratios and MIBI washout seems not to be related to angiogenesis in breast lesions.

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Can Technetium 99m-MIBI-SPECT improve the sensitive diagnostic for localization of parathyroid adenoma?

A comparative analysis of optical and gamma camera imaging for non-invasive detection of ovarian cancer

C.A. Castagnoli (1), L. Vaggelli (1), M. De Feo (2), M. Brandi (2), V. Briganti (1), M. Matteini (1), P. Cicchi (3), F. Tonelli (4), C. Pieroni (1). (1) U.O Nuclear Medicine of Florence, Italy, (2) Department of Endocrinology; University of Florence, Italy, (3) U.O Surgery; Villa Ulivella, Florence, Italy, (4) Department of Surgery of University of Florence, Italy.

T.R. Chaudhuri, Z. Cao, E.E. Partridge, K.R. Zinn. Department of Radiology, University of Alabama at Birmingham, Alabama, USA.

AIM: the purpose of this study was to assess the value of technetium-99m-methoxyisobutylisonitrile (MIBI) single-photon emission tomography (SPECT) compared to conventional planar scintigraphy. METHOD: thirty-three patients with primary or secondary hyperparathyroidism were examined preoperatively with double phase technique. Both planar and tomographic images were acquired 10 and 120 min after intravenous injection of 740 MBq 99mTc-MIBI , using a triple head gamma camera. A thyroid scan with 99mTc was successively performed, at least one day apart, when an hyperactivity was detected in the thyroid bed, to avoid false positives from thyroid nodules. MIBI-Scintigraphy was considered positive for adenoma (PTAs) or hyperplasia (PTH) when a focal area of increased uptake or normal uptake without any washout or with relative progressive increase at delayed images was detected in the neck or mediastinum. Final diagnosis was obtained in all cases with surgery: 8 out of 33 patients were proven hyperplasia (secondary or familiar hyperparathyroidism) while the remaining 25 were PTA . RESULTS: Correct localization of parathyroid adenoma or hyperplastic parathyroid gland was achieved in 22 out of 33 patients (sensitivity 67% ) using planar Tc99m-MIBI imaging. Sensitivity was increased to 91 % ( 30/33) by the additional use of SPECT technique. In 6 out of 22 cases identificated by means of both techniques, SPECT imaging added a better identification of the foci and a better anatomical localization of the focal uptake related to PTA or PTH. Sensitivity in PTA were 68% and 92% respectively for planar and SPECT imaging while 62% and 87% for PTH. We had no false positive cases. CONCLUSION: This study indicates that use of SPECT increases the sentitivity of Tc 99mMIBI - double phase technique for radioisotopic localization of PTAs and PTH.

A comparative study evaluated two imaging modalities to detect established ovarian tumors in nude mice. The basis of the technique was administration of a diagnostic adenoviral (Ad) vector to achieve expression of proteins leading to tumor contrast. Human ovarian tumor cells (SKOV3ip.1) were ip implanted (2x106/mouse) in athymic nude mice (2 groups,10/group) on day 0. On day 15 a replication defective Ad vector (Ad-GFP-hSSTr2) encoding both enhanced green fluorescent protein (GFP) and human type 2 somatostatin receptor (hSSTr2) was ip injected (1x109 plaque forming units) in group 1, while saline was ip injected in group 2. On day 17 the mice were iv injected with hSSSTr2-avid Tc-99m-P2045 (23 MBq, Diatide Research Laboratories). The mice were imaged with both an Anger gamma camera (initial and 5 h) and a fluorescence stereomicroscope (5 h) and terminated for tissue analyses. Gamma camera imaging at 5 h detected hSSTr2 expression in ip tumors of group 1 mice, and GFP was simultaneously imaged in the same tumors. However, fluorescence stereomicroscopy showed greater spatial resolution. Fluorescence provided contrast to visualize 0.2mm diameter tumors. After removal of the abdominal wall, the GFP-positive tumors were visualized even more clearly, including single GFP-positive cells on the peritoneal lining. GFP-positive cells were recovered from peritoneum and cultured in tissue culture media and SKOV3 cells grew. GFP-positive tumors showed significantly higher uptake of Tc-99mP2045 as compared with control tumors. Imaging and cell count data indicated that GFP-positive cells were cancer cells. Control mice did not show expression of either hSSTr2 or GFP. The present study demonstrated the diagnostic utility of Ad-GFP-hSSTr2 administration coupled with light-based imaging to detect small non-palpable ip tumor nodules. Accuracy of light-based imaging was confirmed by gamma camera imaging and quantitative tissue analyses. Clinical imaging to detect hSSTr2 expression can use already approved imaging agents (e.g. NeoTect). GFP expression can be detected with fluorescence endoscopy or fluorescence stereomicroscopy during surgery.

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Lack of correlation of functional scintigraphy using (99m)technetium-methoxyisobutylisonitrile with microvessel density in brain tumors A. Staudenherz (1), S. Wolfsberger (2), M. Killer (2), C. Nasel (3), S. Puig (3), C. Marosi (4), T. Leitha (1), M. Hoffmann (1), J.A. Hainfellner (4). (1) Department of Nuclear Medicine of the University Hospital of Vienna / SMZ-Ost Hospital of Vienna, (2) Department of Neurosurgery of the University Hospital of Vienna, (3) Department of Radiology of the University Hospital of Vienna, (4) Department of Neurology/Oncology of the University Hospital of Vienna, Austria. Aim: Functional imaging of brain tumors assists biopsy localization, therapy monitoring, and differentiating tumor recurrence from radiation necrosis. Tumor vascularization, which is a strong prognostic predictor in solid tumors, is considered as one key factor of tracer uptake. However, the relationship of brain tumor vascularization and functional imaging has not been investigated so far. In the present study we correlated histologically assessed microvessel density as an objective parameter for brain tumor vascularization with imaging data. Materials and Methods: Four male patients were studied. All four patients received 555  MBq (15 mCi) MIBI (Cardiolite ) i.v. The images were acquired using a rotating 3 headed gamma camera (Picker 3000) equipped with a low energy ultra high resolution, parallel-hole collimator. The acquisition was performed within 15 minutes after tracer administration, with 3°/step (30 secs./step) over 360° using 128x128 matrix and an energy window of 15% (centred at 140 keV). MRI was performed on a 1.5 T scanner in the axial and coronal plane with T1w (fast gradient echo technique) and T2w (turbo spin echo technique) imaging. The slicethickness was 3 mm for T2w- and 1.25 mm for T1w- images. For all sequences a field of view of 240x192 mm was used with an acquisition matrix of 256x256 voxels. After administration of contrast medium T1w-imaging was repeated in the axial and coronal plane. After surgery and a routine histopathological workup, anti-CD-34 staining was used according to a standard protocol. Microvessel density was determined in the “hot spot” by counting all vessels at a total magnification of 200x within an examination area of 0.25mm2 using a eye grid. Each stained lumen was regarded as a single countable microvessel. Data are given as total numbers of CD-34 positive cells per microscopical high power field (HPF). Results: Histology showed astrocytoma, glioblastoma (n=2) and anaplastic oligodendroglioma, respectively. Scintigraphy visualized only the glioblastomas, but not the astrocytoma or oligodendroglioma. Microvessel density was lowest in the astrocytoma (57/HPF), medium in the glioblastomas (93/HPF or 127/HPF) and highest in the oligodendroglioma (191/HPF). Conclusion: Our data clearly demonstrate the lack of correlation between tumor microvessel density and 99mTc-MIBI scintigraphy. Thus, we conclude that scintigraphic visualization of brain tumors is not dependent on microvessel density.

Usefulness of Tl-201 spect in the diagnosis of radionecrosis versus tumoral recurrence in low grade glial tumours M.D. Martínez del Valle (1), M. Gómez-Río (1), A. Rodríguez-Fernandez (1), E. López (2), J. Expósito (2), M.J. Acosta-Gómez (1), G. Sabatel (1), S. Ortega (1), J.M. Llamas-Elvira (1). (1) Department of Nuclear Medicine. Virgen de las Nieves University Hospital, (2) Department of Radiotherapy. Virgen de las Nieves University Hospital, Granada, Spain. Introduction: 201Tl has shown to be useful in differential diagnosis of radiation necrosis from viable tumours, especially in high grade glial tumours. However there are some clinical problems in patients with low grade gliomas usually with low radiotracer uptake level. Objective: Expose our experience in the differentiation between tumour recurrence and radiation necrosis in low grade gliomas of the central nervous system, using Tl-201 SPECT. Patients: A total of 38 patients previously diagnosed and treated with low grade gliomas were evaluated for suspected recurrent tumours. Imaging Method: Fifteen minutes after IV injection of 3-5 mCi (111-185 MBq) of 201-TlChloride, a SPECT scan was obtained using a triple-head rotating camera (Prism-3000, Picker-International). We performed 90 frames, 64x64 matrix, 45s/frame. The Uptake index (UI)1 was defined as: average counts-pixel in the Region Of Interest/ average counts-pixel in a contralateral symmetric area. Two different criteria are used for positive report: Criteria A) any focal uptake with an UI>1.2 and <1.5 Criteria B) Any focal uptake (UI >1 and <1.5) in no physiological sites of accumulation of thallium (choroids plexus, scalp) and topographically coincident with the neurostructural region of doubt (single and enhanced CT and/or MRI). The True or False exploration results were established by using the integrated criteria from the Brain Tumours Unit in our cente, based on the paties evolution and survival which are explored; clinically, radiologically, gammagraphically and histopathologically in case of need. Results: Criteria A Criteria B

Sensitivity 73.3 80

Specificity 75 62.5

Comments: In respect to inconclusive neurostructural exploration, in our opinion 201Tl is useful in differential diagnosis of radiation necrosis versus recurrent glioma, but it is necessary to have caution in the criteria for positive results and the clinical repercussion. 1 Kim KT, Black KL, Marciano D et al. Thallium-201 SPECT imaging of brain tumors: methods and results. J Nucl Med 1990; 31(6):965-9.

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Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition NEUROENDOCRINE

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111In-Pentetreotide in preoperative and postoperative evaluation of paragangliomas of head and neck P. Tamayo (1), A. Muñoz (2), F. Morales (3), J.R. García-Talavera (1), R. Ruano (1). (1) Nuclear Medicine Department of University Hospital, Salamanca, Spain, (2) Otorrinolaringology Department of University Hospital, Salamanca,Spain, (3) Neurosurgery Department of University Hospital, Salamanca, Spain. INTRODUCTION. Paragangliomas of head and neck are tumors of neural crest origin that arise from parasympathetic paraganglia. This tumors have a high density of somatostatin type 2 (S2) receptors on cell surface. The aim of this study was to determine the utility of 111In-pentetreotide (Octreoscan®), a somatostatin analog with a high binding affinity for S2 receptors, in the diagnosis and followup of patients with head and neck paragangliomas. PATIENTS AND METHODS. 34 patients were included in this research and divided in two groups. Group 1 consisted of 20 patients with suspected head and neck paragangliomas who had no previous surgery for paraganglioma. In Group 2, 14 patients were evaluated, after previous surgery and/or radiotherapy for paraganglioma, to investigate residual or recurrent tumor. Each patient received a dose of 111 MBq of 111In-pentetreotide intravenously. Whole body scan and spot images of head and neck were obtained at 4 hr and 24 hr after radiopharmaceutical administration. SPECT of head and neck was adquired at 24 hr after inyection when necessary. The results were compared with the histopathology of the surgical specimem and the results of conventional imaging techniques (CT, MRI and angiography). RESULTS. In Group 1, the pentetreotide scintigraphy accurately predicted the presence or absence of paraganglioma in 16 of 20 patients when compared with surgical pathology. 9 patients had positive scan results and 7 patients had negative scan results. There were a falsenegative due to a small (< 6 mm) tympanicum tumor and three false-positives which corresponded to other tumors with somatostatin receptors. Thus the Octreoscan had a sensitivity and specificity of 90% and 60%, respectivily. In one case the scan revealed multicentric involvement and in other one bilateral lesions, which were previously unrecognized and subsequently confirmed pathologically. In Group 2, the pentetreotide scan was positive in 7/14 patients and negative in the others 7 patients, confirming the diagnosis with radiologic techniques. So the Octreoscan had a sensitivity and especificity of 100%. One patient had malignant paraganglioma and other patient had bilateral involment. CONCLUSIONS. 1. 111In-pentetreotide scintigraphy is a usefull tool, highly sensitive, for diagnosis of head and neck paragangliomas. 2. It detects the presence or abscence of residual or recurrent tumor with an accuracy of 100%. 3. Octreoscan is able to detect multicentric lesions and distant metastases.

Patient BIC CIF COE FAB MEM MEL MIT MOC PIV ROG REF MIN SQU MOR INN GRA NEG GIR REM FAA CAO

Organ of origin Pancreas Jejunum Stomach UPS UPS Hileum Pancreas Liver Duodenum Jejunum Jejunum UPS Pancreas Pancreas Pancreas UPS UPS Pancreas Pancreas Ileum Ileum

Metastases Liver Mesenter Nodes Nodes Liver Liver Liver Brain Nodes Liver Nodes -

Previous therapies S, CT, SRT S, CT, SRT, IF S, CT, SRT CT, S S,CT S, CT S, CT, SRT S, CT S, CT, SRT, IF S S, RT S S S, SRT S, SRT S, SRT S, SRT S, SRT S S, CT S

Uptake R I U I R I U U U R U R I R U I U I I U U

n°SRS Follow-up 3 PD 5 SD 3 SD 3 SD 3 Dead 5 PD 3 PD 5 SD 3 SD 3 SD 3 SD 3 PD 3 Dead 3 SD 3 Dead 3 Dead 3 SD 3 PD 3 Dead 3 SD 3 SD

Table I: Summary of the population. UPS unknown primary site, PD progressive disease, SD stable disease. Reduction =R, No change=U, Increase=I. Results Only 3 of the 5 patients in which it was noticed a reduction of OCT uptake showed, as expected, an unfavorable outcome whereas 2 had stable disease. The risk factor of a patient in whom occurs a decrease in OCT uptake during the follow-up is 1.9. On the other hand 9 out of 9 patients with SD did not show a reduction in OCT uptake. Only 2 out of 7 patients with an increased uptake had stable disease, while the others had a poor outcome. Conclusion The scintigraphic evaluation of the changes in the OCT uptake as a prognostic parameter to predict the clinical outcome of GEP patients seems to be an interesting approach. Actually, the reduced density or lack of expression of somatostatin receptors is usually described in poorly differentiated tumors or in those with poor prognosis. However, these preliminary data suggest that the changes in the expression of somatostatin receptors is not the only factor which affects the clinical evolutionof the disease. Other factors probably play a role (pathology, stage, treatments, etc.). To establish the weight of these parameters in comparison to the expression of somatostatin receptors there is a need of further large perspective multiparametric studies.

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G. Savelli (1), A. Chiti (2), S. Fanti (3), S. Bavusi (1), N. Monetti (3), E. Bombardieri (1). (1) Nuclear Medicine Department, Istituto Nazionale Tumori, Milano, Italy, (2) Nuclear Medicine Department, Istituto Clinico Humanitas, Rozzano (Mi) , Italy, (3) Nuclear Medicine Department, Policlinico S. Orsola-Malpighi, Bologna, Italy.

M.J. Acosta-Gómez (1), M.A. Muros (1), J.M. Llamas-Elvira (1), A. Moral (1), M.D. Martínez del Valle (1), A. Ramírez (1), S. Ortega (1), G. Sabatel (1), T. Muros (2). (1) Department of Nuclear Medicine of the Universitary Hospital, Granada, Spain.

Relationship between 111In-pentetreotide uptake and clinical evolution in patients affected by neuroendocrine tumors

Aim. To evaluate the relationship between reduction of 111In-pentetreotide (OCT) uptake evaluated with multiple consecutive planar and SPET scintigraphy and the clinical evolution of neuroendocrine tumors. Materials and Methods. We evaluated 21 patients with gastro-entero-pancreatic neuroendocrine tumors (GEP) who underwent serial somatostatin receptor scintigraphy (SRS) after the i.v. administration of OCT (mean activity 122 MBq). These patients had the standard treatments, including surgery when possible, hormone (octreotide LAR), chemotherapy or biologic response modifiers according to the pathology and grade. The comparison of SRS in the same patient at different times was carried out reporting the 24 hours acquisition. The radiopharmaceutical uptake was assessed with a qualitative evaluation of the planar acquisitions and the results were confirmed evaluating SPET images too. The changes were measured taking as a reference the largest metastatic mass. The trend of OCT uptake was defined as (a) reduced, (b) unchanged, (c) increased. The evaluation of SRS was performed in double blind by two expert nuclear medicine physicians and in case of disagreement the final decision was reached by consensus. Eighteen of these patients had three consecutive examinations and three had five. The disease was classified as progressive or stable on the base of clinical, radiological and biological parameters. The average and the median time between the last SRS and the end of follow-up time were 794 and 650 days respectively (141-2111). Table I summarizes the main clinical parameters of the population studied.

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Recurrent pituitary adenoma: utility of somatostatin receptor scintigraphy.

A potential value of somatostatin receptor scintigraphy is the diagnostic of recurrence of pituitary adenoma in which conventional images (CT or MRI) cannot differ between recurrent tumour or scar. Objective: To determine the utility of somatostatin receptor scintigraphy in patients diagnosed of recurrent pituitary tumours. Material and methods: We evaluated 18 patients (11 female and 7 male) mean age 54,5 years old with suspected recurrent pituitary tumour. Type of tumours included: ACTH secreting adenoma (n=5), GH (n=3), PRL (n=2), non-secreting adenomas (n=7) and FSH (n=1). Clinical data, biochemical analysis, conventional images techniques: Computer Tomography (CT) or MRI and ophthalmologic study (campimetry) were obtained in all patients. An evaluative control was made from 6 months to two years. Scintigraphy with 111In-[DTPA-D-Phe1]octreotide was performed with 185-220 MBq (5-6mCi). Health Department approved the compassionated use of the radiopharmaceutical in all patients. Planar views were obtained at 4, 24 and 48 hours after injection and SPECT was obtained at 4 and 24 hours. Qualitative evaluation of the images was made by two specialists in Nuclear Medicine to describe tracer uptake. Results: Diagnostic of recurrent tumour was made based on clinical status after surgery in 9 patients and persistent high levels of hormonal markers in 9 patients. Somatostatin receptor scintigraphy was positive in 13 patients. The patient with the greater tumoral size was operated, 6 patients were treated with somatostatin analogues, 2 patients were treated with radio-surgery and 3 with medical treatment. One patient denied treatment. Diagnosis of recurrent tumour was confirmed in all patients by improvement of clinical status, biochemical analysis and conventional images after treatment of the recurrent tumour. MRI was negative in two patients with positive scintigraphy in which recurrent tumour was confirmed in the evaluative control. Scintigraphy was negative in 5 patients. Conventional images and evaluative control confirmed the absence of recurrent tumour in 3 patients. In 2 patients recurrent tumour was confirmed by conventional images (CT and MRI) and by clear improvement after treatment. 16 patients of 18 patients evaluated in this study were correctly diagnosed by scintigraphy (88%) while MRI diagnosed 14 patients of 17 patients (81%). One patient was evaluated with CT because his negative to MRI. In our study somatostatin receptor scintigraphy shows a sensibility of 86%, Specify 100% and Positive Predictive Value 100%. The best results of somatostatin receptor scintigraphy in patients with recurrent pituitary adenoma was in ACTH secreting adenoma (Cushing´s disease) and in PRL secreting adenomas. Conclusion: Somatostatin receptor scintigraphy with 111In-octreotide is a non invasive tech-

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n NEUROENDOCRINE nique that allows to diferenciate between scar and recurrent tumour in postoperative patients of pituitary adenoma. Elsewhere it´s high specific in detecting recurrent pituitary tumor. In addition it allows to detect residual tumour in patients operated of pituitary adenoma with negative MRI. Somatostatin receptor scintigraphy allows to select patients who will benefict from medical treatment with somatostatin analogues.

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Comparison of imaging characteristics and clinical efficacy of 111In-DTPA-Octreotide and 111In-DOTA-Lanreotide M. Gabriel, F. Huerter, C. Decristoforo, M. Wenger, K. Hoefler, E. Donnemiller, R. Moncayo. Universitätsklinik für Nuklearmedizin, Universität Innsbruck, Innsbruck, Austria. Aim: In this study the authors evaluated the efficacy of 111In-DTPA-Octreotide (OCT, Octreoscan) and 111In-DOTA-Lanreotide (LAN) scintigraphy for localization diagnostics of somatostatin receptor-(SSR)-expressing tumours in an intra-patient comparison. Method: 24 patients were analysed retrospectively. The study group consisted of cases with non-medullary thyroid cancer (n=8), with medullary thyroid cancer (n=3) and with carcinoid tumours (n=13). Scintigraphy with OCT and LAN was performed within 34 days. Each patient received mean activities of 140 MBq 111In-DTPA-Octreotide and 185 MBq 111InDOTA-Lanreotide intravenously. Whole-body anterior and posterior views were obtained 4h, 24h and optional 48h p.i. with SPET acquisition in ROI´s. Interpretations of these two sets of scintigraphic data were done by two different viewers and the better binding behaviour was defined visually. In case of a positive scan result therapy with somatostatin derivates using 90 Yttrium-labelled or unlabelled compounds was considered. The findings were correlated lesion by lesion with those of conventional radiologic imaging methods (CT, MRI, US, Xray). Results: In all patients 111In-DOTA-Lanreotide showed increased tracer uptake in the spine irrespective of malignant involvement, lower uptake in spleen and image quality increased from 24h to 48h in contrast to 111In-DTPA-Octreotide. Concerning tumour uptake pattern in 9 cases (37.5%) the results were equivalent. In 10 studies (41.7%) 111In-DTPA-Octreotide performed better than 111In-DOTA- Lanreotide in detection capability of malignant foci, whereas in 5 cases (20.8%) 111In-DOTA-Lanreotide appeared to be superior (non medullary thyroid cancer n=3, MTC n=1, carcinoid n=1). In three cases different tumour sites were visualised by the analogues in the same patient (non medullary thyroid cancer n=1, MTC n=1, carcinoid, n=1). Conclusion: Although no statistically significant difference between the scan results was observed (p>0.05), 111In-DTPA-Octreotide seems to have more favourable binding properties in terms of accurate localization in tumour patients. The mosaic pattern in three cases could be a result of a different binding behaviour in SSR-expressing tumour tissue, possibly due to varying expression of receptor subtypes.

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P. Bello (1), I. Hervás (1), J.M. Fernández (2), A. Saura (1), P. GonzálezCabezas (1), D. Flores (1), A. Cañete (2), V. Castel (2), A. Mateo (1). (1) Department of Nuclear Medicine. University Hospital La Fe. Valencia. SPAIN., (2) Department of Paediatric Oncology. University Hospital La Fe. Valencia, Spain.

G. Gopinath, J.R. Buscombe, J.C. Dickson, A.J.W. Hilson. Nuclear Medicine, Royal Free Hospital, London, UK.

AIM: Medulloblastoma (MB) is the most frequent cerebral malignant tumour in childhood. MB expresses somatostatin (SS) receptors, so that MB can be imaged with somatostatin receptor scintigraphy. Complete surgery of these tumours often is not complete, and chemotherapy or radiotherapy are needed to complete the treatment. Conventional imaging (CT/MRI) usually do not allow to distinguish residual tumoral tissue, relapse or unspecific post-treatment changes. Recently somatostatin receptor scintigraphy (SSRS) has been proposed as possible alternative to solve this problem. The aim of this study is to assess SSRS in the follow up of children with MB and to compare it with other imaging techniques and the clinical course of the patients. METHOD: 32 SSRS were performed to 15 patients (6 girls and 9 boys) aged between 15 months and 12 years (mean age 7 years) diagnosed of MB in our hospital during the last two years. All the patients were included in the treatment protocol PNET III SIOP. The post-therapy control was performed using conventional imaging (CT/MRI) and SSRS. SSRS were performed after the i.v. administration of 111In-Octreótide, calculating the individually the dose in order to the weight of patients. Images were acquired at 4 and 24 hours after 111In-Octreotide administration. Planar views of skull (anterior, posterior and laterals), thorax, abdomen and pelvis (anterior and posterior) were obtained in a 250 x 250 matrix, using a high resolution and medium energy collimator. Findings obtained in SSRS were compared with those obtained in CT/MRI and with clinical evolution. RESULTS: From the 32 SSRS performed we have obtained the following correlation: In 13 studies there was total concordance (positive or negative for existence of tumour/relapse) between clinical evolution, conventional imaging techniques and SSRS. In 7 studies the clinical evolution and CT/MRI were positive while SSRS was negative. In 8 studies the clinical evolution and SSRS were negative but CT/MRI positive or doubtfully positive In 4 studies CT/MRI and SSRS were positives but clinical course negative. CONCLUSIÓN: SSRS is a good technique in the follow up of patients with MB and in the differential diagnosis of viable tumour and post-treatment changes.

Difference in Biodistribution of Various Radiolabeled Somatostatin Analogues

Various radiolabeled somatostatin analogues have recently been used for the diagnosis and treatment of the neuroendocrine tumours. At our hospital the most commonly used diagnostic peptide agent is In-111 octreotide and for therapy it is Y-90 lanreotide and Y-90 SMT. The purpose of the study was to identify if there is a difference in biodistribution of these compounds, which in turn will help to predict efficacy and toxicity of the agents. 19 patients with neuroendocrine tumours had a 24-hour whole body In-111 octreotide scan. Within 12 weeks 14 patients received 1GBq Y-90 lanreotide and 5 patients 4 GBq Y-90 SMT. Whole-body Bremsstrahlung imaging at 24-hours post injection of the therapy was performed in all 19 patients. The whole body In-111 octreotide and the Bremsstrahlung images were analysed for the bio-distribution of the radiolabeled isotopes using geometric mean in the following key organs- liver, spleen, heart, bone marrow and kidneys. In-111-octreotide demonstrated a higher activity than the Y-90-Lanreotide and Y-90-SMT in the liver(p=0.042 and p=0.209), and kidneys (p=0.002 and p=0.091) respectively. There is also relatively higher activity of In-111-Octreotide in the spleen with both agents (p=0.004) There is significant difference in biodistribution between In-111 octreotide and Y-90 lanreotide or Y-90 SMT, especially in kidneys, which may explain why there is minimal or no renal toxicity with Y-90 lanreotide and Y-90 SMT therapy. Therefore it may be safe to give high activity of Y-90 lanreotide and Y-90 SMT for therapy.

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Poster Presentation

Assessment of 111In-OCTREOTIDE in the follow up of medulloblastoma in children.

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Proof of the Polyclonality of Carcinoid Tumours A.M. Quigley, J.R. Buscombe, A.J.W. Hilson. Nuclear Medicine, Royal Free Hospital, London, UK. This study was performed to determine if there is a difference in the distribution of lesions on MIBG and somatostatin receptor scintigraphy (SRS) images in patients with carcinoid tumours. 66 patients with histology proven carcinoid tumours underwent SRS and MIBG scintigraphy between 01/01/00 and 31/03/02, with a mean interval of 25 days between scans. The whole body and SPECT images were assessed respectively to determine the number and site of lesions. In 22/66 patients (33%), there was concordance between both examinations in the number and distribution of the lesions identified. In 44/66 (67%) of patients, the scans were discordant. Of these, 13/44 (30%) had more lesions on the SRS and 9/44 (20%) had lesions demonstrated on the SRS alone. 7/44 (16%) had more lesions identified on the MIBG scan, and 4/44 (9%) had a positive MIBG scan, but a negative SRS. In 11/44 (25%) of patients, different lesions were identified on each of the two scans within the same patient. The large number of discordant SRS and MIBG scintigraphy in this study serves to highlight the need to perform both an SRS and MIBG scintigraphy on patients with carcinoid tumours. Given that the mechanisms of uptake of SRS and MIBG are entirely different, and the fact that different lesions were identified on each of the two scans in 44/66 (67%) of patients, demonstrates that the cell types within the tumour are polyclonal in nature.

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Changing pattern of newly diagnosed thyroid cancer during the long time observation J. Nemec (1,2), P. Chytr? (1), P. Racek (2), P. Vlcek (2), V. Zamrazil (1), J. Zimák (2). (1) Institute of Endocrinology, Národní 8, Praha 1, 11694, (2) Clinic of Nuclear Medicine, Teaching Hospital, Praha - Motol. In the IGA Report in 1997 we detected a rising incidence of papillary thyroid cancer. Between years 1951 and 1983, we detected slow and parallel rise of both follicular and papillary cancers. In 1985 and in later years, the number of follicular cancers oscillated at about 50 new cases yearly without any clear-cut trend, while papillary cancers began to rise up to 200 patients yearly. We studied this phenomenon in the presented paper up to the end of year 2000 and discovered that this change was limited to females and to the less advanced cancers T1 . The number of papillary cancers in women with more advanced stages did not change as well as any differentiated cancers in men. This unexpected finding cannot be explained by differences in radioactive fallout, and other factors should be looked for, as eg, better evaluation of thyroid morphology in women; by changing habits in oral contraception that leaves much more possibilities in higher availability of different pharmaceutical products. The rise of T1 cancers is continuing according to preliminary results in 2001. Even the rising iodine supply might influence the thyroid morphology as expected by Deandrea et all. The rising incidence of thyroid microcarcinoma should note pose higher risk for the general population as the clinical impact of these minimal cancers is generally considered to be low. In our preliminary study, only 4% of microcarcinomas showed late appearance of distant metastatic lesions during 40 years follow-up. The increase of T1 cancers is remarkable, as during the years 1976 to 1985 a total of 79 new T1 cancers were diagnosed in females compared to 359 new T1 cancers between 1991 do 2000, eg more than six fold increase. The authors are indebted to IGA, Ministry of Health, Czech Republic , for support of grant NC 5383 – 5

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Z. Bence-?igman (1), A. Kne?eviæ-Obad (1), D. Dodig (1), R. Petroviæ (1), M. Radetiæ (2), T. ?igman (1). (1) Clinical Department of Nuclear Medicine and Radiation Protection of the Clinical Hospital Center and University of Zagreb, Zagreb, Croatia, (2) ENT Department of “Sv.Duh” Hospital, Zagreb, Croatia.

M.P.M. Stokkel, H.I.E. Reigman, J.W.A. Smit. Department of Nuclear Medicine and Endocrinology of the Leiden University Medical Centre, Leiden, The Netherlands.

Follow-up of 504 Patients with Thyroid Carcinoma

Aim: The main idea of this work was to show the value of ultrasound examination (UE) in early detection of thyroid carcinoma (TC) as well as its impact upon the final outcome. Material and Methods: The 504 patients (pts) with TC (399 papillary, 62 follicular, 12 Hürtle cell, 31 medullary) were followed-up for the periods ranging from 0.5 to 35 years (mean 6.3). Total thyroidectomy (TT) was performed in 376 pts. Paratracheal, functional or radical neck dissection with simultaneous TT was done in 107 pts with lymph node metastases (LNM). After TT 458 pts were treated with I-131 for complete ablation of thyroid remnant. Patients with TC were divided into two groups: Group A - pts who underwent UE of the neck region before surgery and in whom tumor and possible lymph node metastases (LNM) were revealed by ultrasonically guided fine needle biopsy (UGFNB) (N= 323), Group B - pts who had not been examined by ultrasound prior to surgery (N=181). Results: In 53% of the analyzed pts TC was recognized by UE due to its typical presentation (hypoechogenous, having irregular margins or tiny calcifications). The pts with LNM had larger TC than those without LNM (p<0.001) as well as pts with distant metastases (DM). TC smaller than 1 cm was found in 134 pts (41.4%) from Group A and in 18 (10%) from Group B. From Group A 11% of the pts and from Group B 36% underwent partial thyroid resection and, subsequently, TT. The rates of additional operations, performed for metastases revealed later, measured 2.4% in the Group A and 16% in the Group B. DM were found in 29 pts (6%), out of whom the 26 pts were treated with additional I-131 therapies, achieving complete remission only in 9 patients. The 11 pts died (2% or 38% of those with DM). Three pts died within 12 months after establishment of diagnosis, 5 pts within 2-5 years and 3 after 10 years. Conclusion: UE and UGFNB make it possible to reveal small TC. They allow detection of possible LNM also, which contributes to the complete healing and makes further treatment much easier and less expensive.

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Indium-111-Octreotide scintigraphy in differentiated thyroid carcinoma metastases that do not respond on treatment with high doses I-131

Aim: Differentiated thyroid cancer is characterized by a very good prognosis in the majority of the patients. The therapy of choice is surgery followed by ablation with Iodine-131 (I-131). However, some patients have metastases that lost the capability of concentrating I-131, even when its given in therapeutic doses. In the present study, we describe the value of Indium-111 Octreotide (Octreoscan) in differentiated thyroid cancer patients with increased Tg levels who failed to demonstrate a response on treatment with a high dose I-131. Materials and methods: 15 consecutive patients with progressive differentiated thyroid cancer (10 female, 5 male) (mean age: 59 yrs, range 13-81 yrs)(8 papillary, 6 follicular and 1 Hurthle cell carcinoma) were studied. Progression was based on increasing Tg levels and it was confirmed by radiological evaluation. Whole body scintigraphy (WBS) was performed after the administration of 200 MBq of Octreoscan. The images were assessed by two experienced observers and compared with post-treatment I-131 WBS. Results: In 7 out of 15 patients distant metastases were already present at initial stage, whereas in 10 patients the primary tumor stage was T3 or T4 indicating that the majority of the patients had advanced disease. In 2 out of 5 patients with a positive I-131 WBS, Octreoscan was false negative. In 9 out of 10 patients with a negative I-131 WBS, Octreoscan demonstrated multiple metastases. In those patients with a positive SSR-scintigraphy, metastases were found in the lungs (n=14), bone (n=7), mediastinum (n=3), liver (n=2), brains (n=1) and cutis(n=1). Overall, 3 out of 15 patients had a negative Octreoscan result revealing a sensitivity of 80%. Conclusion: Our findings demonstrate the diagnostic value of Octreoscan in differentiated thyroid cancer that fails to respond on I-131 treatment. It opens the possibility for additional treatment with high doses of Octreoscan or its analogs in a majority of the patients.

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Limited role of Tc-99m MIBI scan in detecting metastatic foci of thyroid cancer: Comparison with I-131 whole body scan B.C. Ahn, J. Lee, S.Y. Jeong, S.W. Lee, K.B. Lee. Department of Nuclear Medicine of the Kyungpook National University Hospital, Daegu, South Korea, Daegu, Korea. Aim: 99mTc-MIBI scan has been proposed as a diagnostic tool for detecting metastasis or recurrence of differentiated thyroid cancer(DTC), because of convenience without cessation of thyroid hormone. We have prospectively evaluated diagnostic ability of 99mTc-MIBI scan for detection of metastatic lesion in patients with DTC. Material and Methods: Whole body scan and SPECT of the neck/chest with 99mTc-MIBI scan(M-Scan) and 131I whole body scan(I-Scan) was performed in 241 DTC patients(pts) between 2-mo and 25 mo after total thyroidectomy (male/female=39/202, mean age=44±14yr). M-Scan images were acquired with dual head camera (Prism 2000, Picker, USA) at 1 hour after 20 mCi Tc-99m MIBI, and I-scan after 48-72 hr after 2~300mCi 131I for diagnostic or therapeutic purpose. All subjects were in hypothyroid state on I-scan (TSH >30). Diagnosis was made either by biopsy, surgery, or PET findings in addition to clinical features. M-scan and I-scan findings were compared between two tests, regarding to final pathologic diagnosis. Results: Metastatic foci were found in 96 pts(40%) studied. Abnormal lesions were found in 33 among 96 pts(sensitivity 34%), whereas I-Scan detected in 83(sensitivity: 86%). However, 13(46%) among 28 pts with metastasis but negative I-Scan showed abnormal lesions with MScan, and confirmed to be metastatic lesion. I-Scan detected more lesions than M-Scan (23 vs 8 for neck node metastasis, 16 vs 5 for mediastinum metastasis, 14 vs 8 for lung metastasis, and 15 vs 6 for other metastatic sites including bone and soft tissue). All of the lesions less than 1 cm was not visualized with M-Scan. Conclusion: M-Scan revealed lower diagnostic sensitivity for the detection of metastatic foci in DTC pts, especially for small lesions. However, significant amount of lesions but with negative I-Scan were visualized on M-Scan images in DTC pts. These findings suggest that MScan has limited role as a diagnostic tool for detecting metastasis in DTC pts. M-Scan may be useful in pts with high thyroglobulinemia but was not able to localize focal lesion with I-Scan.

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Evaluation of I-131 Whole Body Scintigraphy, Thyroglobulin and Ultrasonography in Recurrent Thyroid Carcinoma M. Franceschi, S. Roncevic, LJ. Lukinac, N. Matesa, Z. Kusic. Department of Oncology and Nuclear Medicine, University Hospital, Zagreb, Croatia.

Date: 02.09.2002 • Time: 14:30 - 16:00 • Hall: Poster exhibition NEW DIAGNOSTIC APPROACHES AND NEW TRACERS

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Radiolabelling of glycosylated MFE23-CPG2 fusion protein with Tc99m-carbonyl to determine biodistribution of active CPG2 enzyme in ADEPT systems. R.J. Francis (1), S.J. Mather (2), K. Chester (1), S.K. Sharma (1), J. Bhatia (1), R. Boden (1), R. Waibel (3), A.J. Green (1), R.H.J. Begent (1). (1) Cancer Research UK Targeting and Imaging Group, Royal Free Campus of Royal Free and University College Medical School, London NW3 2PF, (2) Cancer Research UK Department of Nuclear Medicine, St Bartholomew’s Hospital, London, EC1A 7BE, (3) Paul Scherrer Institute, Center for Radiopharmaceutical Science, Villigen PSI, Switzerland. Background: Radiolabelling of glycolsylated MFE-23-CPG2 fusion protein (MFE-CP1) with technetium-99m (99mTc) was developed to non-invasively determine biodistribution for a proposed phase I ADEPT clinical study. Labelling was directed to the hexahistidine (his) tag of MFE-CP1, which is located on the C terminal end of carboxypeptidase G2 (CPG2), away from the antigen-binding site. The advantages of labelling to the his tag was that the label should not interfere with antigen (CEA) binding and that it would reflect the distribution of CPG2 enzyme, which is the component of MFE-CP1 responsible for prodrug activation in the ADEPT system. Method: The method used was by 99mTc -carbonyl [99mTc(H2O)3(CO)3]+ (abbreviated to TcCO) directed labelling to the his tag of MFE-CP1. MFE-CP1 fusion protein was incubated with TcCO under a variety of conditions. Formation of Tc-99m radiolabelled MFE-CP1 was assessed by HPLC and TLC. CEA binding was measured by a CEA column and confirmed by a cell based Lindmo assay. Tissue biodistribution was assessed in a LS174T (human colon carcinoma) nude mouse xenograft model by the intravenous administration of Tc-99m radiolabelled MFE-CP1. Tissues were taken at 1hr, 4hrs and 6hrs for assessment of distribution of radioactivity and for measurement of CPG2 enzyme level (HPLC). Results: Technetium carbonyl labelling of MFE-CP1 after PD10 purification resulted in >95% purity by HPLC and TLC. CEA binding was retained (61-77% by CEA column). Biodistribution studies show very high uptake and retention of radioactivity in the liver, spleen and kidneys. The radioactivity was rapidly cleared from blood, colon, lung and muscle. There was some retention of activity in the tumour. Liver, kidney, lung, spleen and tumour were analysed for CPG2 enzyme activity. There was good correlation between CPG2 enzyme activity measured in tumour and Tc-99 labelled MFE-CP1 localisation. Correlation between CPG2 enzyme activity and measured radioactivity in liver, spleen and kidney was poor, indicating retention of radioactivity, without active enzyme. Conclusion: Biodistribution studies of Tc-99m radiolabelled MFE-CP1 confirmed the hepatic clearance of this glycosylated product. The amount of radioactivity retained by the tumour proved to be a good estimation of actual measured enzyme activity, indicating that this radiolabelling method does not appear to damage the antibody-antigen binding or the enzyme activity of MFE-CP1. It may therefore provide a good estimate of antibody-enzyme localisation for ADEPT therapy. Unfortunately however, the high retention of Tc-99m radioisotope in normal tissues (liver, spleen, kidney) may limit the clinical applicability of this method at present.

Poster Presentation

Aim: Iodine-131 whole body scintigraphy (WBS) and serum thyroglobulin (Tg) measurement are routinely used techniques to follow-up the patients (pts) with differentiated thyroid carcinoma. In this study we compared I-131 WBS, serum Tg measurement and neck sonography (US) and sonographically guided fine-needle aspiration biopsy (FNAB) in the detection of local recurrence of thyroid carcinoma. Methods: Radioiodine WBS was obtained in 401 pts with prior thyroidectomy and radioiodine ablation of the thyroid remnant. Serum Tg levels were determined during suppression and suspension of thyroid hormone therapy. Neck US was obtained in all pts and US guided FNAB using 22-25 gauge needles was performed in 106 pts with sonographic features suggesting malignancy. Results: I-131 WBS was positive in 7 pts with neck metastases. Increased serum Tg levels (>1ng/mL) were found in 31 of the pts with neck lymph node metastases and/or recurrence in the thyroid bed. Neck US with US-guided biopsy revealed malignant cells in 40 pts, 28 of whom had lymph node metastases. In seven of twelve pts with recurrences in the thyroid bed, lymph node metastases were found as well. Conclusions: While I-131 WBS is well established diagnostic method to detect metastases in pts with differentiated thyroid carcinoma, numerous studies demonstrated that serum Tg measurement is even more sensitive indicator of recurrent disease. However, our study indicates that neck US and US-guided FNAB is method of choice to reveal regional recurrences.

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A Novel Tumor-Seeking Agent for Malignant Melanoma based on Specific Enzyme of Melanin Formation: 3-Iodo-4-HydroxyphenylCysteamine R. Nishii (1), K. Kawai (2), K. Nishimura (2), S. Kinuya (3), T. Uehara (3), S. Nagamachi (1), Y. Arano (4), N. Tonami (3), S. Tamura (1). (1) Department of Radiology, Miyazaki Medical College, Miyazaki, Japan, (2) Faculty of Medicine, Kanazawa University, Ishikawa, Japan, (3) Graduate School of Medical Sciences, Kanazawa University, Ishikawa, Japan, (4) Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan. A Novel Tumor-Seeking Agent for Malignant Melanoma based on Specific Enzyme of Melanin Formation: 3-Iodo-4-Hydroxyphenyl-Cysteamine PURPOSE: The aim of our study is to develop a new radiopharmaceutical labeled with radioiodine for detection and therapy of tumors, which have affinity to a characteristic metabolism in tumor. 3-Iodo-4-hydroxyphenyl-L-cysteine (I- L-PC), which we have reported previously, was found to have an interaction for tyrosinase, an essential and rate-limiting enzyme to melanin biosynthesis. In this study, considering higher affinity for tyrosinase, we synthesized 3-iodo-4-hydroxyphenylcysteamine (I-PCA) that was an amine derivative of I-L-PC and examined biodistribution study in melanoma-bearing mice. METHOD/MATERIALS: 4-Hydroxyphenylcysteamine (4-PCA) was synthesized and radioiodinated in our laboratory. Synthesis of 4-PCA was confirmed by 1H-NMR, mass spectrometry and elemental analysis. 125I-PCA was prepared by conventional chloramine-T method under a no-carrier added condition. 125I-PCA was purified by Sep-Pak-C-18 cartridge and the labeling efficiency and radiochemical purity were examined by TLC analysis. Biodistribution study of I-PCA was performed using B16 melanoma-bearing C57BL6 mice. The radioactivities of each organ were measured and % injected dose / g wet tissue was determined. Moreover, the tumor-to-blood ratio (T/B ratio) and tumor-to-muscle ratios (T/M ratio) of 125IPCA were also evaluated and were compared with 125I-L-PC, 67Ga-citrate, 125I-L-AMT and 123IMIBG. RESULTS: Radiosynthesis of 125I-PCA was carried out conveniently and efficiently within only 15 min. A labeling efficiency of more than 73 % resulted in the labeling of 4-PCA to 125IPCA. After the simple Sep-Pak purification, no-carrier added 125I-PCA with radiochemical purity greater than 90 % was obtained. The biodistribution of 125I-PCA showed rapid blood clearance, renal excretion and low accumulation in normal tissue, while increase of accumulation in the tumor for 30 min. As a consequence, T/B ratio reached approximately 1.6 ± 0.3 and T/M ratio increased up to 8.7 ± 3.2 at 60 min after injection. It was higher than those of 125I-LPC; 6.5 ± 0.8 and 67Ga-citrate; 4.6 ± 0.4. It indicated specific retention of the tracer in the melanoma. CONCLUSIONS: The results suggested that I-PCA achieved the desired affinity for melanin formation. That is, I-PCA has high potentiality for diagnosis of malignant melanoma. Moreover, because I-PCA accumulated low in normal tissue and showed rapid clearance, it might be applied as a therapeutic radiopharmaceutical when labeled with I-131.

P_175

Hypoxia-induced alteration of tracer accumulation in cultured cancer cells and xenografts in mice: implication for pre-therapeutic prediction of treatment outcomes with Tc99m-sestamibi, Tl201 chloride and Tc99m-HL91 S. Kinuya (1), K. Yokoyama (1), X.-F. Li (1), J. Bai (1), T. Michigishi (1), N. Tonami (1), N. Watanabe (2), N. Shuke (3). (1) Department of Biotracer Medicine, Kanazawa University, Kanazawa, Japan, (2) Department of Radiology, Toyama Medical and Pharmaceutical University, Toyama, Japan, (3) Department of Radiology, Asahikawa Medical College, Asahikawa, Japan. Weak visualization of tumors in pre-therapeutic scintigrams with 99mTc-sestamibi (MIBI) is likely a sign of unfavorable tumor response to radiotherapy and chemotherapy. However, factors relating to this scintigraphic finding are not well understood. The presence of hypoxic tumor cells is one of the major reasons for therapeutic failure; consequently, we attempted to determine whether oxygenation status affects 99mTc-MIBI accumulation in tumor cells. Methods: LS180 human colon cancer and T24 human bladder cancer cells were incubated in air or N2 gas at 37oC. Cellular uptake of 99mTc-MIBI was subsequently determined at 15, 60 and 120 min. Uptake of 201Tl chloride was also assessed. Uptake of 99mTc-HL91 was assessed as a hypoxic marker. Accumulation of the tracers in LS180 xenografts was observed in mice treated with 5 mg/kg hydralazine and compared to that in non-treated mice. pO2 in the medium and tumors was measured with O2 microelectrodes. Results: N2 gas flow gradually reduced pO2 in the cell suspension to 1-2 mmHg in 60 min. Cellular uptake of 99mTc-MIBI in LS180 cells decreased approximately 30% in N2 gas in comparison to that in air throughout the study. The influence of hypoxia was more prominent on 201 Tl uptake, which displayed reduction of approximately 60% in N2 gas at 120 min, than on 99m Tc-MIBI uptake. On the other hand, N2 gas induced an increase of 170% in 99mTc-HL91 uptake at 120 min, indicating the hypoxic condition of cells. The results of in vitro assays employing the T24 cell line were similar to those obtained with the LS180 cell line. Hydralazine treatment markedly reduced 99mTc-MIBI and 201Tl accumulation in LS180 xenografts; moreover, intratumoral pO2 decreased from 14.5 ± 6.6 mmHg to 7.56 ± 6.2 mmHg. 99mTc-HL91 accumulation in xenografts was markedly increased by hydralazine. Conclusion: Hypoxia reduced accumulation of 99mTc-MIBI and 201Tl in tumor cells. Accordingly, hypoxia may be an important factor in terms of the interpretation of scintigraphic findings of these tracers for pre-therapeutic prediction of tumor response to treatment. Furthermore, enhanced 99mTc-HL91 accumulation in hypoxic tumor cells indicates the usefulness of this tracer in this regard.

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S. Koukouraki (1), E. Sanidas (2), A. Velidaki (1), I. Askoksilakis (2), V. Prassopoulos (1), D. Tsiftsis (2), N. Karkavitsas (1). (1) Department of Nuclear Medicine of the University Hospital of Iraklion, (2) Department of Surgery Oncology of the University Hospital of Iraklion, Iraklion, Crete, Greece.

I. AK (1), V. ASLAN (2), E. VARDARELI (1), Z. GÜLBAS (2). (1) Department of Nuclear Medicine of the Osmangazi University Medical Faculty, Eskisehir, Turkey, (2) Department of Haematology of the Osmangazi Univeristy Medical Faculty, Eskisehir, Turkey.

The role of carcinoembryonic antigen immunoscintigraphy in the diagnosis of breast carcinoma: preliminary results

Purpose: It is accepted that a negative mammography doesn’t exclude breast malignancy. Recently 99mTc sestamibi was used as a complement to mammography tool for difficult diagnostic cases. Nowadays antibodies against tumor associated antigens have been proposed as more specific tumor imaging agents. The purpose of this study was to evaluate the role of antiCEA scan in the detection of breast malignancy. Materials- Methods: Thirty women with 31 palpable lesions with histologically proven malignancy were studied before undergoing surgery. All of them underwent scintimammography using 99mTc sestamibi and 99mTc anti CEA. For sestamibi scintimammography 25 mCi of radiotracer was given i.v in the contralateral arm and for CEA scan 20mCi. A ? camera GE Millennium equipped with a LEGP collimator was used for both scintigrams. There was a minimal interval of three days between CEA and MIBI scan. Multiple planar views were obtained 20 min after the iv injection of 99mTc sestamibi and 4 hours after 99mTc CEA. Images were classified as positive, indeterminate and negative. Results: CEA scan showed malignancy in 24 /34 lesions (true positive) and was false negative in 7/34. Lesions smaller than 1.5 cm were not detected. Conclusion: Despite the small number of our cases, CEA scan seems to have high affinity to detect breast malignancy but its sensitivity for lesions <1.5 cm is still under evaluation.

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Tc99m-MIBI bone marrow imaging in patients with multiple myeloma: does it reflect the level of plasma cells in bone marrow

Aim: The percentage of myeloma cells in bone marrow is an important index of disease activity in patients with multiple myeloma (MM). Bone marrow plasma cells from patients with MM can be detected by exploiting their strong CD38/CD138 positivity and light scatter characteristics using the flow cytometry. The aim of this preliminary study was to evaluate the relationship between degree of Tc-99m MIBI uptake and the percentage of CD38/CD138 expressing myeloma cells in the bone marrow of patients with MM. Methods: A total of 10 patients with active MM (4 f, 6 m) were included the in the study (mean age 62.1±9.6 yrs). Eight controls had known coronary artery disease and no haematological disorders were also included in the study. Images were obtained 20 min post injection of 740 MBq Tc99m-MIBI. A single head GE 4000i AC/T camera with a LEHR collimator was used for image acquisition. Planar spot images of the pelvis and thorax were acquired. The uptake of the MIBI was determined using a semiquantitative 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. In all patients, flow cytometry was performed for assessing the percentage of Results: There was statistically significant difference in mean MIBI uptake between patients with MM and controls (1.88±0.4 and 0.85±0.2, p<0.001, respectively). A positive and statistically significant correlation was found between Tc99mMIBI uptake of bone marrow and the percentage of CD38/CD138 expressing plasma cells detected by flowcytometry (r=0.79, p<0.01). Conclusion: This preliminary report suggests that increased Tc99m-MIBI uptake of bone marrow is related to percentage of myeloma cell of bone marrow in patients with MM. Therefore, Tc99m-MIBI bone marrow imaging may be a useful tool for predicting the levels of myeloma cells in bone marrow in diagnosis and monitoring of patients with MM.

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n NEW DIAGNOSTIC APPROACHES AND NEW TRACERS scintigraphy with 99mtc-technetril for diagnostics of thyroid tumors G.A. Davydov (1), N.A. Olejnik (1), A.A. Semyonova (2), N.A. Nerozin (2), D.V. Stepchenkov (2). (1) Medical Radiological Research Center of Russian Academy of Medical Sciences, (2) State Scientific Center of Russian Federation - Institute of Physics and Power Engineering. Obninsk, Russia. The Department of Isotopes and Radiopharmaceuticals of the SSC RF IPPE has developed the production technology of Technetium-99m generators, which scale up to the international quality level. The generators activity is 0.1-4.0 Ci, the quality parameters meet the requirements of the Russian Pharmacopoeia, BP and USP. The MRRC RAMS evaluated an effectiveness of clinical application of the mentioned Technetium-99m generators for preparation of radiopharmaceuticals with various cold kits and subsequent diagnostic procedures. This evaluation has shown the eluate high quality. Aim. This investigation aim is to evaluate an effectiveness of clinical application of the radiopharmaceutical 99mTc-technetril: research of the information content provided by the scintigraphy with 99mTc-technetril used for diagnostics of thyroid tumors. Technetium-99m-technetril (foreign functional analog is MIBI) is a pharmaceutical made in Russia (by company “Diamed”), it is a complex of Technetium-99m with copper salt of 2methoxyisobutylisonitrile. Materials and methods. The radiopharmaceuticals based on the eluates obtained from Technetium-99m generators and Technetril have been prepared in the hospital. 190 patients aged from 8 to 78 with nodules in the neck area (34 men, 156 women) have been examined. The scintigraphy of the neck and breast area with the thyrotropic radiopharmaceutical 99mTctechnetril prepared in the hospital was carried out for every patient. 177 patients were operated and the diagnosis was confirmed by histology. The thyroid benign tumors were revealed in 101 patients. Results. Despite the cancer histologic form 58/74 patients (78,4%) had the hyperfixation of Technetril in “cold” nodules. 62/74 (83,8%) patients with the thyroid cancer diagnosed for the first time had the increased accumulation of Technetril. 14/15 (93,3%) patients experiencing the thyroid cancer recurrence had “hot” foci in the operated thyroid bed and in the areas of regional and distant metastatic spreading. 13 patients had pseudo negative results, the papillary cancer was diagnosed in 11 of them, and in the most cases (11/13) the tumor dimensions were small (less than 0.9 cm3). All the nodules looked like “cold” foci during the scintigraphy with 99mTc-technetril of the group of patients with the thyroid benign tumors. Conclusions. The scintigraphy with the radiopharmaceutical 99mTc-technetril is a test providing with much information for diagnostics of the thyroid cancer (sensitivity – 85,4%, specificity – 77,2%, accuracy – 81,1%). It may be recommended for the differential diagnostics of thyroid tumors.

P_178

Study of the Effect of Potassium Perchlorate on the Expression of Sodium Iodide Symporter (NIS) in Human Breast Cancer P.K. Pradhan, B.K. Das, G. Agarwal, S.K. Mishra, M.M. Godbole. Departments of Nuclear Medicine and Endocrinology (Medical and Surgical), Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India. OBJECTIVES: Several experiments indicate that Sodium Iodide Symporter (NIS) is expressed in breast cancer. However, the nature and function of NIS particularly in respect of iodine transport and its inhibition is not well established. The objective of this study was to characterise the pattern of inhibition of Technetium Pertechnetate (TPT) uptake in human breast cancer by Potassium Perchlorate (KClO4) in comparison to normal breast tissue and thyroid. METHOD: Ten female patients with FNAC confirmed malignancy (stage I to III) were included in the study. After i.v. application of 555 MBq (15 mCi) of 99mTc04 (TPT), images of breast and thyroid gland were acquired, the patient lying in prone position over a scintimammography cushion pad for the breast and in supine position for the thyroid. Sets of similar images were taken on the second day 30 min. after oral administration of 500 mg KClO4 (Sigma) dissolved in 100 ml water. A dual headed gamma camera system (DST XL, SMV, France) was used for imaging and data processing. Semi quantitative estimation of TPT uptake in the thyroid, cancer tissue and non-affected breast was done using ROI technique. Uptake ratios were calculated from the images acquired before and after application of KClO4. RESULTS: Thyroid to background (BG) ratio decreased significantly (up to 5 times) after application of KclO4 whereas BG to breast tumour ratio increased (up to 60%) after application of perchlorate. Similar results were also observed in BG subtracted ratios between the tumour and normal tissue of the other breast. CONCLUSIONS: (a) There is enhanced concentration of TPT in breast tumour suggesting high NIS expression. (b) TPT uptake is significantly suppressed by perchlorate in thyroid and normal breast but not in tumour tissue of the breast suggesting a different mechanism of handling of Potassium Perchlorate by NIS in tumour tissue. (c) The inhibition of TPT uptake by Perchlorate in mice tumour reported recently appears not to be applicable to human breast tumour.

P_179

A new bispecific antibody (bsAb) pretargeting system for improved immunoscintigraphy D.M. Goldenberg (1), R.M. Sharkey (1), G.L. Griffiths (2), W.J. McBride (2), H. Karacay (1), E. Rossi (3), K. Chang (3), H.J. Hansen (2). (1) Garden State Cancer Center, Belleville, New Jersey, USA, (2) Immunomedics, Inc., Morris Plains, New Jersey, USA, (3) IBC Pharmaceuticals, LLC, Morris Plains, New Jersey, USA. Several bsAb pretargeting systems have been developed that can be used in a variety of imaging applications, including SPECT and PET. BsMAbs have been prepared by chemical conjugation or by recombinant molecular engineering of a humanized anti-carcinoembryonic antigen (CEA) antibody (hMN-14) paired with antibodies directed against indium-loaded DTPA (734) or histamine-succinyl-glycine (HSG; 679). Pretargeting studies in tumor-bearing mice using the hMN-14 x 734 F(ab’)2 BsMAb with a divalent DTPA peptide containing a 99mTcbinding chelate achieved tumor/blood and tumor/kidney ratios of 7:1 and 5:1, respectively, within 3 hr of the peptide’s injection, compared to a directly 99mTc-hMN-14 Fab’ with no tumor/organ ratio exceeding 1:1 at the same time. A recombinant-engineered bsAb composed of scFv from the anti-CEA and anti-HSG antibodies has shown superior tumor/nontumor ratios compared to a chemically-conjugated anti-CEA x anti-HSG F(ab’)2 using an 111Inlabeled divalent HSG peptide, suggesting that engineered bsAbs may provide additional advantages for pretargeting imaging applications. The HSG pretargeting system represents a significant advancement because of its flexibility; unlike other bsAb systems, the anti-HSG antibody is not responsible for binding the specific effector molecule. Thus, divalent HSGcontaining peptides can be synthesized to bear a variety of ligands to optimize radionuclide binding; for example, HSG-peptides capable of binding 99mTc and 111In have been prepared with similar in vivo targeting properties as the other pretargeting system. With superior targeting ratios as compared to directly-radiolabeled antibodies, the use engineered humanized antibodies to eliminate agent immunogenicity, and an ability to adapt this system to use in immunoscintigraphy with SPECT or PET agents, these bsMAb pretargeting systems may provide next-generation imaging modalities for improved cancer detection and diagnosis.

P_180

Application of Oral Contrast Media in Co-Registered PET-CT Imaging E. Dizendorf, V. Treyer, G. K. von Schulthess, T.F. Hany. Division of Nuclear Medicine, University Hospital, Zurich, Switzerland. Objective: Co-registration of positron emission tomography (PET) and computer tomography (CT) images benefits from significantly improved localization of pathological FDG uptake compared to PET images alone. For delineation of intestinal structures, application of oral contrast media is a standard procedure in CT. The influence of oral contrast agent in PET imaging when using CT data for attenuation correction was evaluated in a comparative study on an in-line PET-CT system. Methods: A total of 60 patients referred for PET-CT imaging were evaluated in two groups. One group of 30 patients received oral Gastrografin 45 minutes prior to data acquisition. The second group received no contrast media. PET images were reconstructed using CT data for attenuation correction. Image analysis was performed by two independent reviewers in consensus, using a 4 point-scale comparing FDG-uptake in the gastrointestinal tract in PET images of both groups. Furthermore, correlation of FDG uptake and localization of contrast media in the intestinal tract in CT images was determined. Results: No significant difference in FDG uptake in PET images was seen between both groups regarding all regions of the gastrointestinal tract except the ascending colon. No correlation was found in the location of increased FDG uptake and contrast media in the CT images. Conclusion: Oral contrast agent can be used for co-registered PET-CT imaging without introduction of artifacts in PET imaging.

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The role of Tc-99m-MDP scintimammography in the evaluation of breast lesions

The contribution of scintimammography with 99m-Tc tetrofosmin in the diagnosis of breast cancer

A.M. Fawzy (1), K. Abdel Dayem (2), H. Amer (2), H. Hosny (2). (1) Nuclear Medicine and, (2) Surgical Departments, Kasr El Aini, Hospital, Faculty of Medicine, Cairo, Egypt.

K.V. Vonorta (1), D.B. Baltas (2), N.B. Bredakis (2), N.S. Stefanakos (1), K.A. Anagnostopoulos (1), S.P. Papageorgiou (3), A.G. Giatas (2), A.K. Keramopoulos (2), V.P. Prassopoulos (1). (1) Nuclear Medicine Dpt.,IASO Hospital, (2) Breast Dpt.,IASO Hospital, (3) Medical Physics Dpt.,IASO Hospital, Athens,Greece.

Tc-scintimammography is becoming an increasingly complementary tool in the evaluation of breast lesions. Tc-99m MDP is a known bone scan agent which is widely used allover the world, and is used also in the evaluation of soft tissue lesions. Aim of the Work: To validate the role of Tc-MDP scintimammography in the evaluation of breast lesions and correlate the results to histopathological diagnosis. Patients and Methods: 43 female patients with breast lesions were included in this study. Each of them were injected with 740 MBq (20 mCi) of Tc-99m MDP IV and the patients were subjected to two set of images at 10 minutes and 2 hours, each comprising of an anterior supine view and two lateral prone views. Those patients were later subjected to pathological diagnosis either by open surgery or fine needle biopsy. Results: The mean age of the patients was 35.98 + 14.1 years (range 12 – 70). The size of the mass ranged between 0.8 cm x 0.8 cm up to 10 x 7 cm (mean 3.07+1.8 x 2.6+1.3). We had 25 benign lesions and 18 malignant lesions in our patients. In the benign lesions the early uptake was negative in 17 patients (68%) and positive in 8 patients (32%). While in the late images, negative uptake was seen in 22 patients (88%) and positive uptake in 3 patients (12%). Those 8 patients with positive early uptake were as follows: 2 TB, 1 chronic abscess, 1 phylloide tumor, 2 fibroadenoma and 2 inflammatory masses. Furthermore, in the 18 malignant patients, 17 showed positive early uptake (94%), and 1 was negative (6%) and this was due to occult carcinoma metastasizing in lymph nodes. While, in the late images, 15 patients were negative (83%) and 3 positive (17%). Lymph node uptake was evident in only 1 patient of the study group (2.3%). Sensitivity is 94%, specificity (64%), false positive value (36%), false negative value (6%), positive predictive value (54%), negative predictive value (96%) and accuracy (73%). Conclusion: Early Tc-MDP scintimammography is a valuable and cheap method for the evaluation of breast lesions.

Introduction: It is already known that breast cancer is the most common malignancy of women.Breast mammography,although it is of a great importance as a screening test, it has some limitations.This results in the necessity of the use of other imaging procedures. In the present study the contribution of scintimammography with 99-m Tc Tetrofosmin in the diagnosis of breast cancer is investigated. Material-Method: 91 women aged 22-72 y.o. with strong clinical and/or mammographic suspicion of breast cancer (92 lesions) were investigated.All patients uderwent scintimammography with 99-m Tc Tetrofosmin (dose:20mCi) before biopsy. An i.v. injection was performed at the contralateral site of the suspected lesion.Imaging was performed 10min.postinjection.Patients were at a prone position and lateral and anterior views of the breasts and axillary areas were performed(10min/view,matrix size 128x128,high resolution collimator). Results: The overall Sensitivity was 85,7%,Specificity was 87,9%,Positive Predictive Value was 81,9%,Negative Predictive Value was 90,7% and Diagnostic Accuracy was 85,3%.3/3 local relapses were detected,as well as 1/1 bilateral involvement.In a case of negative brest scan and positive findings at the axillary area, histology revealed a lymphoma. Conclusion: Scintimammography with 99-m Tc Tetrofosmin is a valuable method in the detection of primary breast cancer or the early diagnosis of local relapses.It is statistically superior from other imaging modalities that are used complementary with mammography in what it concerns sensitivity, specificity, Positive Predictive Value, Negative Predictive Value.

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P_184

G. Sabatel (1), A. Rodríguez-Fernandez (1), M.D. Martínez del Valle (1), M. Gómez-Rio (1), J. García (2), S. Menjón (2), C. Ramos (1), R. Arenas (1), J.M. Llamas-Elvira (1). (1) Department of Nuclear Medicine. Virgen de las Nieves University Hospital., (2) Department of Radiotherapy. Virgen de las Nieves University Hospital, Granada, Spain.

M. Ortega (1), X. Setoain (1), JJ. Mateos (1), F. Martín (1), I. Bladé (2), X. Tomás (3), S. Fuertes (1), D. Fuster (1), F. Pons (1). (1) Nuclear Medicine Department, Hospital Clínic Barcelona, Spain, (2) Hematology Department, Hospital Clínic Barcelona, Spain, (3) Radiology Department, Hospital Clínic Barcelona, Spain.

OBJECTIVE: Expose our experience using 99mTc-Tetrofosmín in terms of diagnosis accuracy in the evaluation of patients with clinical or radiological criteria of Breast Cancer. PATIENTS AND METHODS: Thirty two patients (n=32; Mean Age= 52.1±5.3) under clinical (by palpation) and/or radiological suspicion of malignity in primary lesion (27/32) or local recurrence (5/32) in previously diagnosed disease. Our study population was subjectively classified as intermediate pre-test probability of malignancy. The exploration protocol includes: both lateral and anterior projections in breast designed bed, 5-10 min. after I.V. radiotracer injection and tomography (SPECT) (7/32) when the specialist wasconsidered it necessary. Confirmation of diagnosis was made using Fine Needle Biopsy in lesion of interest or histopathological study from the surgical sample. RESULTS: Studies were classified as : True Positives: 15 patients; False Positives: 4 pts; True Negatives: 11 pts.; False Negatives: 2 pts. Global diagnostic accuracy: Sensibility: 0.88; Specificity: 0.73; Probability for Positive Exploration: 0.78; Probability of Negative Exploration: 0.75. COMENTARY: With the limitations from the selection bias in our study population (intermediate pre-test probability: 17/35) we considered useful the use of 99mTc-Tetrofosmin to establish the tumoral nature of lesions in patients under clinical doubt and with no conclusive results in no invasive procedures.

The therapeutic approach to multiple myeloma (MM), according to Durie &Salmon classification, depends on the presence of bone injury. Until now, the routine diagnostic method has been serial bone X-ray , but this does not detect all bone lesions. Objectives: i) To determine the feasibility of 99mTc-MIBI scintigraphy in the diagnosis of patients with MM and compare the results with those obtained with X-ray. ii) To decide the best acquisition time for an accurate diagnosis. Method: We studied 12 patients with MM (mean age 58 years) in a transplant program and a control group of 11 (mean age 61 years). We performed whole-body scintigraphy with 740 MBq of 99mTc-MIBI at 15 minutes and 2 hours. In those patients with MM, a serial bone Xray was also performed. Results: In 12/12 (100%) patients with MM an abnormal uptake was observed in the MIBI scintigraphy; 6 of them presented a diffuse MIBI uptake, 4 presented focal uptake and the remaining 2, both diffuse and focal uptake. Nine out of the 11 controls showed no MIBI bone uptake, whilst with the other 2, a mild and diffuse uptake in the spine was observed. The serial X-ray showed focal lesions in 5/12 (42%) patients. Five out of the remaining 7 patients without visible lesions on X-ray were found to have generalized osteopenia and arthrosis. In the cases where scintigraphy and X-ray presented as pathological, the scintigraphy detected more lesions. The early scintigraphy images presented a lesion/background relation higher than in the later images. Conclusions: i) MIBI scintigraphy can be a usefulness technique in the spread diagnosis of MM. It detects more lesions than the X-ray. ii) The early scintigraphy (at 15 minutes) seems to be the more useful.

99mTc- tetrofosmin (myoview) in breast cancer

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Diagnosis of multiple myeloma using 99m-Tc-MIBI scintigraphy

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I. AK (1), F. ALTINEL (2), Z. GÜLBAS (3), E. VARDARELI (1). (1) Department of Nuclear Medicine of the Osmangazi University, Medical Faculty, Eskisehir, Turkey, (2) Department of Neurosurgery of the Hospital of the Social Security Institution, Eskisehir, Turkey, (3) Department of Haematology of the Osmangazi University, Medical Faculty, Eskisehir, Turkey.

C. Batsakis (1), G. Panoutsopoulos (1), A. Rapti (2), V. Giannakopoulos (1), A. Balomenos (1), A. Diona (1), J. Chritsacopoulou (1). (1) Nuclear Medicine Dept, General Hospital , (2) 8th Pulmonary Clinic, General Hospital , Athens Greece.

Aim: Tc99m-MIBI has been proposed for using as an imaging agent for various tumours including brain tumours. Multiple studies have demonstrated that S-phase fraction is a reflection of proliferation potential of a tumour and DNA aneuploidy is more common in malignant tumours. In this preliminary study, we assessed the Tc99m-MIBI uptake of brain tumours and its relation to the DNA content of the tumoural cells. Methods: A total of 10 patients with brain tumours were included the in study (8 m, 2 f, mean age: 53.2±6.11 yrs, range 4-76 yr). SPECT imaging was obtained 20 min. post injection of 740 MBq Tc99m-MIBI. A single head GE 4000i AC/T camera with a LEHR collimator was used for image acquisition. The region of interest (ROI) was drawn in the tumour area on a transverse slice with the guidance of MRI findings. A MIBI uptake index was computed as the mean tumour-to-background ratios. All of patients underwent excision of the mass and DNA analysis of the tumour was immediately obtained from fresh tumour tissue specimens by the flow cytometry. The percentage of the cells in G0/G1, S and G2/M phases of the cell cycle were measured for each patient. Results: DNA aneuploidy was found in 4 (49%) patients, whereas diploidy was found in 6 (60%) patients. S-phase fraction was more than 10% in all of the aneuploid tumours (mean 18.2%, range 11-25%). There was a statistically significant positive correlation between the MIBI uptake index and the percentage of the S-phase fraction of the cell cycle (p= 0.000 r= 0.95). Tc99m-MIBI index was significantly higher in aneuploid tumours (140.17 ± 21.6) than that of diploid (54.11± 11.2) tumours, (p<0.01). Conclusion: Although limited numbers of the patients, this preliminary report suggests that Tc99m-MIBI SPECT imaging may use for evaluation of the biological characteristics of brain tumours, showing increased uptake of Tc99m-MIBI according to cellular DNA content and proliferative fraction of the tumour.

Tc-99m-Depreotide imaging in the evaluation of solitary pulmonary nodules

Background and aim of the study: Lung cancer is one of the most prevalent cancers and the leading cause of cancer mortality in Europe and the USA. Twenty five per cent of new cases of lung cancer are presented as solitary pulmonary nodule (SPN). The diagnostic pathways in evaluating SPNs involve techniques that are definitely accompanied by discomfort and risk to the patients while they do not always give a definite diagnosis, resulting approximately in 60% of unnecessary operations in benignities. The best non-invasive diagnostic approach has proved to be imaging with PET-FDG. However, this method has the disadvantage of high cost and limited availability. Small-cell-lung cancer as well as non-small-cell-lung cancer exhibit a divergent over-expression of the different subtypes of somatostatin receptors (SSTR). This has lead to the use of somatostatin analogs in order to differentiate malignancy from benignity on SPN. In-111 octreotide has been initially used for scintigraphic imaging and staging of small cell lung cancer with moderate results. Tc99m depreotide which is a synthetic peptide that binds with divergent affinity to the five known somatostatin receptors has recently been introduced in the evaluation of SPNs. Experience from the use of Tc99m depreotide is limited internationally. Patients and Method: We have studied 20 patients with indeterminate SPNs with a diameter ranging from 8 mm to 6.5 cm. The radiopharmaceutical is supplied in vials containing 50 mg lyophilized depreotide peptide. Once reconstituded the vial requires a 10 minute incubation step in a boiling water bath. The patient dose is 25-50 mg depreotide radiolabelled with 740 MBq Tc99m, administered intravenously. SPECT as well as planar images were obtained between 150-180 minutes following injection. Histology revealed 8 benign lesions (six TBC granulomas, one hamartoma and one aspergiloma) and 12 malignant (one metastatic, eight NSCLC and three SCLC. Results: Tc99m depreotide scan was negative in all benign lesions. Out of twelve malignant lesions positive findings were obtained in eight. There were missed one case of SCLC, two cases of squamous cell carcinoma as well as the metastatic lesion. The smallest depicted lesion was 16mm in diameter. The size of missed lesions ranged from 10 – 20 mm. In one case apart from the pulmonary nodule, lymph nodes of the mediastinum bilaterally were shown whish proved to be metastatic. Nodules with a diameter greater than 3 cm were also seen in planar images. In some cases the up take of the lesion was satisfactory but in three cases the nodules were imaged faintly. Conclusion: It is encouraging that we did not have any false positive results. However for a complete clinical evaluation of this new radiopharmaceutical, more cases should be examined.

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A. Tutus (1), M. Kula (1), B. Eser (2), H.I. Sari (2), S. Tutus (3), A. Unal (2), M. Cetin (2). (1) Erciyes University, School of Medicine, Department of Nuclear Medicine, (2) Erciyes University, School of Medicine, Department of Hematology, (3) Erciyes University, School of Medicine, Department of Radiology, Kayseri, TURKEY.

J.W. Seok (1), I.J. Kim (1), Y.K. Kim (1), J.Y. Kim (2), S.G. Wang (2). (1) Department of Nuclear Medicine of the Pusan National University Hospital, (2) Department of Otolaryngology of the Pusan National University Hospital, Pusan, Korea.

Comparison of technetium-99m tetrofosmin and gallium-67 citrate scintigraphy in the assessment of lymphomas

Aim: The aim of this study was to compare Tc-99m tetrofosmin scintigraphy and Ga-67 scintigraphy in the diagnostic assessment of patients with lymphomas and to relate these results with those of radiological evaluation. Material and methods: Thirty untreated patients (20 M, 10 F, aged 21- 70 years) with biopsy proven lymphomas (22 non-Hodgkin’s and 8 Hodgkin’s) were studied with Tc-99m tetrofosmin scintigraphy and then with Ga-67 scintigraphy before any therapeutic intervention. Posttreatment investigations were also done in 18 of the 30 patients after first chemotherapy cycle. All patients had computed tomography (CT) of the neck, chest, abdomen and pelvis; and sometimes sonography of the neck or abdomen. Results: The diagnostic accuracy of Tc-99m tetrofosmin and Ga-67 imaging for lesion detection was 68% and 86%, respectively. A total of 9 unknown tumor lesions in 5 patients were discovered on Tc-99m tetrofosmin and Ga-67 scans. Tc-99m tetrofosmin failed to visualize infradiaphragmatic 24 lesions in 9 patients, but 12 of 24 lesions visible on Ga-67 images. The tumor-to-background ratio was 1.64 +/- 0.54 (ranged from 1.36- 2.12) for Tc-99m tetrofosmin and 2.10+/- 0.63 (ranged from 1.28- 3.48) for Ga-67. A response to treatment was demonstrated by a reduction in localized pathological uptake (Tc-99m tetrofosmin and Ga-67) in 12 of 18 patients, and by the disappearance of uptake in 6 of 12 patients. Conclusion: Tc-99m tetrofosmin scintigraphy may be considered an alternative to gallium scanning for the localization supradiafragmatic tumor lesions and the prediction of therapy outcome in patients with lymphomas. However, the intense Tc-99m tetrofosmin activity in the lower chest and abdomen limits the diagnostic sensitivity of this radionuclide technique in patients with lymphomas.

Regional Detection of Cervical LN Metastasis in Head and Neck Cancer with Tc-99m MIBI SPECT

Purpose: In head and neck cancer, it is very important to detecting cervical LN metastasis for decision of staging. The aim of this study was to evaluate diagnostic value of Tc-99m MIBI SPECT for the detection of cervical LN metastasis in head and neck cancer. Materials and Methods: Tc-99m MIBI SPECT was performed at 10 minutes after injection of 740 MBq of Tc-99m MIBI on 12 patients (10 males, 2 females, mean age=58.8yr) who were performed surgery of head and neck tumors with cervical LN dissection. All LN lesions were subdivided according to anatomical position (level I, IIa, IIb, III, IVa, IVb, V). We interpreted LN metastasis by the anatomical level. Results: Among 112 cervical LN levels, metastatic lesions were 6 and negative lesions were 106. Tc-99m MIBI SPECT revealed 6 TP, 0 FN, 9 FP, and 97 TN. The sensitivity and specificity for head and neck cancer were 100% and 91.5%, respectively. In the accuracy of Tc99m MIBI for the detection of each level LN metastasis, level IIb was 1 FP, level III was 1 FP, and level V was 7 FP. If level V was excluded, sensitivity and specificity were 100% and 97.8%, respectively. Conclusion: Our study revealed that Tc-99m MIBI SPECT was very useful for detection of cervical LN metastasis in head and neck cancer.

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Poster Presentation

Tc99m-MIBI uptake in patients with brain tumours: correlation with cellular DNA content of tumour

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G.M.M. Gommans (GMM), A. van Dongen (1), R.O. Boer (1), F.M. van der Zant (1), J.W.D. de Waard (2). (1) Department of Nuclear Medicine Westfries Gasthuis, (2) Deparment of Surgery Westfries Gasthuis, Hoorn, The Netherlands.

J.W. Seok (1), S.J. Kim (1), H.S. Kwak (2), I.J. Kim (1), Y.K. Kim (1), Y.T. Bae (2). (1) Department of Nuclear Medicine of the Pusan National University Hospital, (2) Department of General Surgery of the Pusan National University Hospital, Pusan, Korea.

Introduction: in the Netherlands in a National Health Program, women between 50-75 are screened biennial for breast carcinoma Aim: the aim of this study was to investigate whether scintimammography could be helpful in the primary diagnosis of non-palpable lesions for breast cancer and to justify performing a sentinel node procedure and lumpectomy simultaneously. Methods: 45 females (age 50-75y, mean age 58y) were presented with a non-palpable lesion of the breast, seen at the screening-X-ray-mammography. All patients were send to our hospital for further evaluation. In all patients the X-ray mammography was repeated. Within oneweek echo and scintimammography were performed. All patients were investigated scintigraphically 5 min. after intravenous injection of 700 99mTc-MIBI. Anterior, left and right lateral images (10-min acq. 256*256 matrix) were obtained. The scintimammography was analyzed visually (blinded of results X-ray and Echo) by 2 observers for detectability of the non-palpable lesion(s). Results: results of scintimammography were compared with PA reports. 34/45 patients underwent surgery. In this group, compared with PA, we found 18TP; 3FP; 10TN and 3FN results. (spec. 86% and sens. 77%). In 11/45 patients, at base of the results of the repeated X-ray, echo and scintimammography surgeons decide against surgery. Follow-up X-ray-mammography 6 months later did not show malignancies in this group. Reporting all 45 screened patients; scintimammography showed a PPV of 86% and a NPV of 91%. Conclusion: scintimammography in non-palpable breast lesions can be helpful to make a decision between operating the non-palpable lesion and to perform a sentinel node procedure in one or, if necessary in two settings.

Purpose: The aim of this study was to compare the Tc-99m MIBI scintimammography (SMM) and contrast enhanced MRI in patients with suspected breast cancer and investigate whether Tc-99m MIBI SMM provide more information in case of indeterminate findings of contrast enhanced MRI. Materials and Methods: This study included 150 suspected breast cancer patients. All patients were performed SMM and contrast enhanced MRI. The SMM and contrast enhanced MRI were correlated with histopathologic results. The pathologic results were obtained by operation and by FNAB. Results: One hundred forty breast lesions were diagnosed malignant diseases and 10 were diagnosed benign diseases. SMM showed 120 true positives (TP), 13 true negatives (TN), 5 false positives (FP), and 12 false negatives (FN). The sensitivity and specificity were 90.9% and 72.2%, respectively. Contrast enhanced MRI revealed 119 TP, 10 TN, 3 FP, 1 FN and 17 indeterminate cases. The sensitivity and specificity were 90.2% and 55.6%, respectively. Among 17 indeterminate cases with MRI findings, SMM correctly diagnosed malignant breast diseases in 10 lesions and benign breast disease in 5 lesions. However, SMM showed 2 FN. SMM could correctly diagnose malignant and benign breast diseases more 15 lesions than contrast enhanced MRI. Conclusion: In this study, SMM revealed higher specificity in detection of primary breast cancer than contrast enhanced MRI. SMMs could correctly diagnose malignant and benign breast diseases in cases with indeterminate MRI. Therefore, SMM may have complementary role in patients with indeterminate MRI finding.

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Scintimammography a imaging technique for diagnosis of non-palpable breast carcinoma

Comparison of Tc-99m MIBI Scintimammography and Contrast Enhanced MRI in Suspected Breast Cancer Patients

Immunoscintigraphy with the IMMU-4 99mTc Fab’ anticea in the detection of recurrent colorectal cancer

Usefulness of 99mTc-HYNIC-tyr3-octreotide for differential diagnostics of solitary pulmonary nodules - preliminary communication

D. Fuster (1), F. Martín (1), J. Maurel (2), A. Muxí (1), X. Setoain (1), M.L. Ortega (1), S. Fuertes (1), P. Paredes (1), F. Pons (1). (1) Department of Nuclear Medicine of Hospital Clínic, Barcelona University, Barcelona, Spain, (2) ICMHO of Hospital Clínic, Barcelona, Spain.

A. Plachcinska (1), R. Mikolajczak (2), A. Markiewicz (2), B. Gorska (2), A. Michalski (3), K. Rzeszutek (3), J. Kozak (4), E. Mlodkowska (1), J. Kusmierek (1). (1) Department of Nuclear Medicine, Medical University, Lodz, Poland, (2) Department of Radiopharmaceuticals, Radioisotope Center POLATOM Otwock/Swierk, Poland, (3) Center for Pulmonary Diseases, Lodz, Poland, (4) Department of Thoracic Surgery, Copernicus Hospital, Lodz, Poland.

Aim: To determine the sensitivity and specificity of immunoscintigraphy with the IMMU-4 Fab’ antiCEA (CEAScan) for early detection of colorectal recurrence in patients with rising serum CEA levels. To compare the results obtained using CEAScan with CT findings. Material and methods: Fifty-one patients (27 women, 24 men) with colorectal cancer (mean age 68.9 ± 10.2 yr) and rising CEA levels (68.4 ± 9.3 mg/ml) were studied. Two immunoscintigraphy studies were performed in 8 patients (n=59). Immunoscintigraphy was performed after i.v. injection of 925 MBq of CEAScan. Planar images of the thorax and the abdomen as well as SPECT of the abdomen were obtained at 4 and 24 hours after injection. In all cases an abdominal CT scan was previously performed. Findings were validated by histopathological analysis (28 lesions) or by imaging and clinical follow-up of at least 6 months following the immunoscintigraphy (31 lesions). Results: Nineteen patients did not show recurrence during follow-up. We found 18 cases of abdominal extra-hepatic recurrences, 11 liver metastases, 9 in the lung and 1 case of bone metastasis. Immunoscintigraphy was positive in 18 cases (14 true positive, 4 false positive). From the 14 true positive only 7 lesions were detected by CT. Immunoscintigraphy was negative in the remaining 41 cases (37 true negative, 4 false negative).Therefore, the sensitivity and specificity for immunoscintigraphy were 81% and 86%, respectively. CT results showed a low sensitivity of 61% with a similar specificity of 83%. Liver metastases were detected by CT in 9 cases, but only 2 of these were identified using immunoscintigraphy. Conclusion: Scintigraphy with CEAScan is better than CT for the detection of extrahepatic abdominal recurrence of colorectal cancer. However, CT is more sensitive in the detection of liver metastases. Both methods have proved to be complementary in the follow-up of patients with suspected recurrence.

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Introduction: Overexpression of somatostatin receptors in various malignant tumors prompted search of somatostatin analogs, which, after radioactive labeling, could be used in oncological diagnostics. The 99mTc-HYNIC-Tyr3-octreotide, a 99mTc labeled conjugate of HYNIC with Tyr3-octreotide, is a new receptor bound radiopharmaceutical (RPh), developed in Poland, that now undergoes clinical trials. The purpose of the present study was the assessment of the RPh’s usefulness for differential diagnosis of solitary pulmonary nodules (SPN), detected in lung radiograms, into malignant and non-malignant tumors. Material and methods: The study included 25 patients with solitary pulmonary nodules of diameter between 2 and 6 cm. In all patients a full clinical verification was secured, including bacteriological, cytologic and histologic examinations. In 18 patients pulmonary cancer was diagnosed (in 16 non-small cell ca. and in 2 small cell ca.). In 7 remaining patients nonmalignant tumors were found (4 tuberculomas, 3 nonspecific granulomas and 1 nonspecific infection). In all patients receptor scintigraphy was performed, using 99mTc-HYNIC-Tyr3Octreotide. The activity of the latter, administered i.v. amounted to ~ 740 MBq. The scintigraphy was performed applying SPECT procedure 2 hours post-injection, using high resolution collimator and 128x128 image matrix. Accumulation of activity was evaluated in 3 sets of reconstructed cuts: transverse, coronal and sagittal, concentrating on elevation of the uptake in regions of interest corresponding to localization of the SPN, as seen in radiograms. The accumulation of activity in tumors was evaluated in a 4-grade score: 0 - lack of increased uptake, 1 - slight uptake, 2 - evident uptake and 3 - pronounced uptake (comparable to the uptake in liver). Results: In all 18 malignant tumors there was a notable uptake of the RPh: in 15 - pronounced and in 3 –evident (on the average 2.8,sd-0.4). In 2 of the 7 benign lesions there was no RPh uptake, in the other 3 -slight, in 1- evident and 1- pronounced accumulation. Mean score in benign lesions amounted to 1.1 (sd-1.1) and was significantly lower than in malignant tumors (p < 0.001). Conclusions: 99mTc-HYNIC-Tyr3-octreotide demonstrates a potential usefulness for differentiation between malignant and benign etiologies in SPN. Optimal use of the differentiating properties of the RPh will require application of quantitative assessment of the uptake and derivation of quantitative criteria optimizing the diagnostic efficacy.