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Objecives: Recently, imaging biomarkers like flouro-deoxi-glucose positron emission tomography (FDG-PET) become even more important for evaluation probable AD. The aim of this study was to evaluate the possible correlation between Montreal Cognitive Assessment Test (MoCA) and metabolic function of brain regions determined by FDG-PET in patients with probable AD. Materials and methods: Thirty seven (37) patients who had diagnosis of probable AD were included. MoCA test and metabolic measurements of brain regions by FDG-PET were performed in all patients. A visual scoring was performed to obtain the rates of hypometabolism in brain regions. Results: Median age of the patients was 77 (minimum 65-maximum 83) years. On the right hemisphere, MOCA test score decreased according to visual FDG-PET score of parietal lobe (15±5.1, 11.8±8.4 and 8.5±5.9; p=0.032). MOCA test score was 16±5.8, 13.1±7.6 and 9.1±6.1 in patients with left temporal lobe and 15.2±5.2, 11.8±7.8 and 8.5±5.9 in patients with left parietal lobe according to visual FDG-PET scores respectively (p=0.035; p=0.02). The comparison of the other right and left hemisphere regions and MOCA test scores were not significant. Conclusion: The present study is emphasized that the MoCA test which is easily applied in outpatient clinics can be demonstrated the hypometabolism of bilateral parietal and left temporal brain regions related with pathophysiology of AD.

The aim of this study was to assess the early therapy response in patients with unresectable CCA who received Y-90 microsphere therapy for CCA and define the factors related to therapy response. Data of 19 patients [extrahepatic (n: 6) and intrahepatic (n: 13)] who received 24 sessions of Y-90 microsphere therapy [glass (n: 13) and resin (n: 11)] were retrospectively evaluated. Tumor load, tumor size, therapy response evaluation by RECIST1.1 criteria (n: 13), tumor lesion glycolysis (TLG), metabolic tumor volume (MTV), and metabolic therapy responses were evaluated (n: 8) using PERCIST1.0 criteria. No significant relation was found between therapy response and tumor localization, treated liver lobe, type of Y90 microspheres, the presence of previous therapies, perfusion pattern on hepatic artery perfusion scintigraphy, or patient demographics. The mean overall survival (OS) was 11.9 ± 2.3 months and was similar after both resin and glass Y90 microspheres; however, it was longer RECIST responders (p: 0.005). MTV and TLG values significantly decreased after therapy, and ΔMTV (− 45.4% ± 12.1) was found to be positively correlated with OS. No statistical difference was found between iCCA and eCCA, in terms of OS and response to therapy. Although not quantitatively displayed, better-perfused areas on HAPS images had a better metabolic response and less perfused areas were prone to local recurrences. Both resin and glass microsphere therapy can be applied safely to iCCA and eCCA patients. Early therapy response can be evaluated with both RECIST and PERCIST criteria. Both anatomical and metabolic therapy response evaluations give complementary information.

A girl diagnosed with neuroblastoma at 33 months underwent I-MIBG scan after surgery and chemoradiotherapy. Although MIBG scan showed complete response, the bone marrow biopsy showed refractory disease. Therefore, she underwent Ga-DOTATATE PET/CT, which revealed bone marrow involvement and Ga-DOTATATE-avid brain metastasis. Rare physiological pineal gland uptake was also depicted. Ga-DOTATATE PET/CT showed active progressive disease earlier, before it was detectable with MIBG scan. For patients with MIBG-negative relapsed/refractory disease, Ga-DOTATATE may have an important role in restaging, detecting unsuspected metastasis, therapy planning.

Amac: Medikal tedaviye direncli epilepsi hastalarinda nobet semiyolojisi, skalp-video elektroensefalografi, manyetik rezonans goruntulume (MRG) ve 18-floro-2-deoksi-glukoz pozitron emisyon tomografi (FDG-PET) bulgularinin degerlendirilmesi, epileptojenik odagi lokalize etmede klinik- elektroensefalografi bulgulari ile norogoruntuleme yontemleri arasindaki uyumun degerlendirilmesi amaclandi. Gerec ve Yontemler: Retrospektif olan calismamiz hastane etik kuru onayi alinarak yapildi. Calismaya, Ocak 2011 ile Ocak 2017 tarihleri arasinda, klinik- elektroensefalografi bulgularina gore temporal (30 erkek, 26 kiz, ortalama yas 30,1±8,9 yil) ve ekstra-temporal lob epilepsi (29 erkek, 23 kiz, ortalama yas 22,8±10,9 yil) gruplarina ayrilan ardisik 108 hasta (59 erkek, 49 kiz, ortalama yas 26,6±10,5 yil) dahil edildi. Kategorik-sayisal degiskenler t, Mann-Whitney U, McNemar veya Ki-kare testi ile analiz edildi. Bulgular: Calismaya dahil edilen 108 hastanin 12’si (6 erkek, 6 kiz, ortalama yas 28,7±10,2 yil) epilepsi cerrahisi gecirdi ve bu hastalarin operasyon sonrasi ortalama takip suresi 32 aydi. Klinik- elektroensefalografi bulgulari ile norogoruntuleme yontemleri arasinda en yuksek uyum (%76) hippokampal skleroz disi anormallikler sahip temporal lob epilepsili hastalarda saptandi. MRG’de kortikal gelisimsel anormalliklere sahip hastalardaki, klinik- elektroensefalografi bulgulari ile MRG arasindaki uyum (%84,2), klinik- elektroensefalografi bulgulari ile FDG-PET arasindaki uyumdan (%52,6) yuksekti (p=0,010). T emporal lob epilepsilerindeki k linik- elektroensefalografi bulgulari ile norogoruntuleme yontemleri arasindaki uyum (%48,2), ekstra-temporal lob epilepsilerine (%9,6) gore daha yuksekti (p

Objective: Epilepsy surgery has shown efficacy in children. We aimed to assess long-term seizure outcome in children who underwent epilepsy surgery and determine predictive factors for seizure freedom.& nbsp;Methods: This is a retrospective study of 196 children who underwent epilepsy surgery between 1994 and 2015 and had a minimum postoperative follow-up of 5 years.& nbsp;Results: The median age at the time of surgery was 9.5 (0.08-19.8) years; 110 (56.1%) had temporal, 62 (31.6%) had extratemporal resections, and 24 (12.2%) had hemispheric surgery. The duration of postsurgical follow-up was between 5 and 20 years (mean +/- SD: 7 +/- 3.2). Overall, 129 of 196 (65.8%) patients had Engel class I outcome at final visit. Among patients who underwent temporal, extratemporal and hemispheric surgery; 84 of 110 (76.4%), 34 of 62 (54.8%), and 11 of 24 (45.8%) patients had complete seizure freedom, respectively (p: 0.016). Patients with tumors had the best outcome, with 83.1% seizure freedom. The number of preoperative antiseizure medications (OR 3.19, 95% CI 1.07-9.48), the absence of postoperative focal epileptiform discharges (OR 8.98, 95% CI 4.07-19.79) were independent predictors of seizure freedom. Across two decades, the age at surgery was decreased (p: 0.003), overall seizure freedom (61.8% vs 68%) did not differ. In the past decade, a higher proportion of malformations of cortical development was operated (14.7% vs 35.9%, p: 0.007).& nbsp;Significance: Our findings showed favorable long-term seizure outcome in children who underwent epilepsy surgery. The results are encouraging for developing centers with limited resources to establish pediatric epilepsy programs.

Öz toprak Ü, Yalnızoğlu D, Karlı-Oğuz K, Lay-Ergun E, Söylemezoğlu F, Bilginer B, Akalan N, Topçu M, Turanlı G. The seizure semiology consistent with frontal lobe symptomatogenic zone in children. Turk J Pediatr 2016; 58: 583-591. The aim of this study is to analyze the seizure semiology consistent with frontal lobe symptomatogenic zone in childhood. We analyzed 549 videotaped seizures from 79 patients (mean age 9.9 ± 3.8 years). Magnetic resonance imaging was normal in 30 patients. The seizures in the time interval of 10 p.m. to 6 a.m. were considered as nocturnal. The mean number of seizures per patient was 6.8 ± 7.3. The mean seizure duration was 25.7 ± 26.9 sec; postictal confusion was 27 ± 16.1 sec (7-92 seconds). The seizures were observed in sleep with a rate of 56.8%; 43.1% of them were during wakefulness. Overall 50.4% of the seizures occured during night-time sleep. Tonic seizure (77.2%) was the most frequent simple motor seizure. Versive seizures were the second most frequent type of simple motor seizure (26.7%). Clonic seizures were 17.7%, complex motor seizures were 20.5%, and dialeptic seizures were 3% of all the seizures. Epileptic spasm, myoclonic seizures, aphasia, and akinetic semiologies were not observed. Vocalization was observed in 16% of the seizures.Frontal lobe seizures in childhood have a short duration, occur frequently, especially during night time sleep, and have a brief postictal period. Tonic semiology, versive semiology are the most frequent seizure semiologies; hypermotor and secondary generalized tonic clonic seizures and vocalizations are observed less in children compared to adults Öz toprak Ü, Yalnızoğlu D, Karlı-Oğuz K, Lay-Ergun E, Söylemezoğlu F, Bilginer B, Akalan N, Topçu M, Turanlı G. The seizure semiology consistent with frontal lobe symptomatogenic zone in children. Turk J Pediatr 2016; 58: 583-591. The aim of this study is to analyze the seizure semiology consistent with frontal lobe symptomatogenic zone in childhood. We analyzed 549 videotaped seizures from 79 patients (mean age 9.9 ± 3.8 years). Magnetic resonance imaging was normal in 30 patients. The seizures in the time interval of 10 p.m. to 6 a.m. were considered as nocturnal. The mean number of seizures per patient was 6.8 ± 7.3. The mean seizure duration was 25.7 ± 26.9 sec; postictal confusion was 27 ± 16.1 sec (7-92 seconds). The seizures were observed in sleep with a rate of 56.8%; 43.1% of them were during wakefulness. Overall 50.4% of the seizures occured during night-time sleep. Tonic seizure (77.2%) was the most frequent simple motor seizure. Versive seizures were the second most frequent type of simple motor seizure (26.7%). Clonic seizures were 17.7%, complex motor seizures were 20.5%, and dialeptic seizures were 3% of all the seizures. Epileptic spasm, myoclonic seizures, aphasia, and akinetic semiologies were not observed. Vocalization was observed in 16% of the seizures.Frontal lobe seizures in childhood have a short duration, occur frequently, especially during night time sleep, and have a brief postictal period. Tonic semiology, versive semiology are the most frequent seizure semiologies; hypermotor and secondary generalized tonic clonic seizures and vocalizations are observed less in children compared to adults

OBJECTIVE Metamizol, probably with its vascular smooth muscle relaxant effect, enhances rest myocardial perfusion with the use of technetium-99m-methoxyisobutylisonitrile. We aimed to investigate whether metamizol induction is also able to increase the detectability of the ischemic/jeopardized myocardium during thallium-201 myocardial perfusion scintigraphy (MPS). METHODS Twenty patients who had partially reversible/irreversible perfusion defects on their routine stress-redistribution-reinjection thallium-201 MPS were enrolled and metamizol-induced thallium-201 MPS (111 MBq thallium-201 was injected 45 min after 1 g oral metamizol) was acquired (10 min, 1 and 3 h later). Routine MPS and metamizol-induced MPS images were interpreted on the model of 17 segments using a visual uptake score (VUS; 0=normal, 1=mild, 2=moderate, 3=significant decreases, 4=no uptake). Thallium-201 uptake ratios (mean counts in the region of the perfusion defect/mean counts in the region of the normal-perfused wall) were calculated for each MPS. Blood pressure was monitored at 15-min intervals. MPS were compared with coronary angiography results. RESULTS Visual uptake score and thallium-201 uptake ratio results indicated that in the first and third hour metamizol-induced thallium-201 uptake was significantly higher (P

Tc-99m dimercaptosuccinic acid (DMSA) renal cortical scintigraphy (RCS) of a 46-year-old man with abdominal and right flank pain who had history of a tendency toward thrombosis revealed extensive renal parenchymal changes secondary to renal infarction and a small size defect in the right kidney in addition to the patient's prior computed tomography results. The patient had Coumadin treatment. Two months later, he was referred to the hospital with the same symptoms. DMSA RCS established that the small defect in the right kidney had enlarged; other scarred areas persisted. This case indicates the value of DMSA RCS for early diagnosis, follow-up of acute/recurrent renal parenchymal scarring in patients with thrombophilia.

This study aims to investigate whether induction with metamizol, an analgesic-antipyretic drug having spasmolitic activity, could be used to increase the detectability of ischemic/jeopardized myocardium during MPS (myocardial perfusion scintigraphy).Metamizol-enhanced rest MPS (45 min after administration of 1 g metamizol orally, 740 MBq (99m)Tc sestamibi was injected, MPS was acquired 45 min later) was performed in 21 patients who had perfusion defects on their previous stress-rest (99m)Tc sestamibi MPS. Blood pressure was monitored at 15-min intervals. Stress, rest, metamizol-rest MPS images were interpreted on the model of 20 segments using a visual uptake score (VUS; 0 = normal, 1 = mild, 2 = moderate, 3 = significant decreases, 4 = no uptake). (99m)Tc sestamibi uptake ratios (MIBI-UR; mean counts in the region of the perfusion defect/mean counts in the region of the normal-perfused wall) were obtained on each MPS and compared with each other. Average MIBI-UR in each scintigraphic examination was calculated. MPS were compared with coronary angiography results.VUS and MIBI-UR results showed that metamizol-rest MPS displayed the defect reversibility better than rest MPS. Of the 14 segments with fixed perfusion defects on stress-rest MPS, 8 showed improvement of perfusion after metamizol induction. In 33 segments, lesion reversibility was better delineated on metamizol-rest MPS. Metamizol-induced sestamibi uptake was significantly higher (p0.001) than stress/baseline rest examinations as calculated by the MIBI-UR. Blood pressure remained unaltered. Coronary angiography results were in concordance with metamizol induced MPS.Metamizol-enhanced rest MPS increases detectability of ischemic/viable myocardium during MPS. Metamizol should be discontinued like nitrates before stress MPS since it may mask the visualization of ischemic perfusion defects.

Reflex seizures can be triggered by a variety of stimuli. We present a case with drug-resistant complex partial seizures originating in right temporal lobe triggered extensively by visual, auditory, and mental exposure to multidigit numbers. The patient was investigated in video-EEG monitoring unit and seizures were triggered by numerical stimuli. Scalp EEG findings suggested a right temporal focus but ictal semiological findings suspicious for an extratemporal area necessitated the invasive EEG study. A right anterior temporal seizure focus was established with invasive monitoring and cortical stimulation studies. Magnetic resonance imaging showed a cortical dysplasia in right anterior temporal lobe and ictal single-photon emission computed tomography confirmed the epileptogenic focus, leading to a right temporal lobectomy and amygdalohippocampectomy and a pathological diagnosis of focal cortical dysplasia type Ia. The patient is seizure-free at the end of the second postoperative year despite repeated exposures to numbers. To our knowledge, this is the first report of seizures triggered by numbers. It is also of particular importance as the reflex seizures are associated with a cortical lesion and it may suggest involvement of right anterior temporal lobe in numerical processing.

Lymphatic leak is a common cause of perirenal fluid collection in renal transplant patients in whom early recognition and therapy is essential for the survival of the kidney. Nuclear medicine offers dynamic renal scintigraphy for the evaluation of renal perfusion, function, and recognition of urologic complications. We present a renal transplant recipient in whom renal scintigraphy showed abnormal radiotracer collection adjacent to the bladder, which caused urinary stasis in the renal pelvis. Lymphoscintigraphy, which can be used to identify lymphatic collections, revealed abnormal radiotracer accumulation in the transplant fossa and confirmed that the perirenal fluid collection was the result of a lymphatic leak. We have described a patient with perirenal fluid collection after renal transplantation surgery in whom lymphoscintigraphy was used to confirm the diagnosis.

This paper describes a novel approach for designing drug delivery systems for intra-articular (i.a.) treatment of rheumatoid arthritis. Retention of these systems was evaluated by radiolabeling with Tc-99m and gamma scintigraphy in arthritic rabbits. Liposome, niosome, lipogelosome and niogelosome formulations of Diclofenac Sodium (DFNa) have been prepared and drug release properties and in vitro characterisation studies have been carried out. According to characterisation results L1 (DMPC: CHOL: DCP (7:1:2)), L1J1 (DMPC: CHOL: DCP (7:1:2) in C-940 1:1 (w/w)), N (SUR I: CHOL: DCP (7:1:2)) and NJ1 (SUR I: CHOL: DCP (7:1:2) in C-940 1:1 (w/w)) formulations were chosen for the further studies. Retention time of these formulations was evaluated by gamma scintigraphic imaging studies. Rabbits with antigen-induced arthritis were injected intra-articularly with Tc-99m labelled drug delivery systems. Serial scintigraphic images were obtained to investigate the retentions of labelled drug delivery systems in the arthritic joints and choose a suitable formulation for the treatment protocol of arthritis. At the end of the scintigraphic imaging studies it was observed that radiolabelled lipogelosome formulation containing DFNa (L1J1) retained much longer in the experimentally arthritic knee joints of the rabbits. This formulation was used for the treatment protocol of arthritis. Mono articular arthritis was induced in the knee joints of rabbits and it was monitored at regular time intervals by measuring changes in knee joint diameter. Also macroscopic and histopathologic evaluations were performed for further evaluation of arthritis. Great retention of DFNa in the arthritic joint might reduce potential adverse systemic effects of the drug because of local administration into the diseased area. It appeared to be a promising drug delivery system for intra-articular drug delivery.

Radionuclide renography with angiotensin converting enzyme (ACE) inhibition plays an important role in the diagnosis of haemodynamically significant renal artery stenosis. Angiotensin receptor antagonists inhibit the renin angiotensin system at different levels from ACE inhibitors by selectively blocking the binding of angiotensin II to AT1 receptors. The AT1 angiotensin receptor antagonist losartan has recently been used clinically in the treatment of hypertension. However, the available data on the use of losartan with renography for the detection of renovascular hypertension are limited and contradictory. The purpose of this prospective study was to compare the effectiveness of losartan renography and captopril scintigraphy in revealing renal artery stenosis. A total of 61 renal units in 32 patients with hypertension were studied in two groups based on the losartan dosage (50 mg in group A and 100 mg in group B). Group A consisted of 17 patients, in whom 19 renal units had angiographically proven renal artery stenosis (≥50%). In group B, there were 15 patients, in whom 20 renal arteries were stenotic. All of the patients underwent three renographies (baseline, captopril renography and early losartan renography). Early losartan renography was performed at 1 h after oral losartan administration in both groups. In group B, seven patients underwent additional losartan renography (late losartan) performed 3 h after oral losartan administration; these patients composed group B1. The sensitivities of captopril and losartan studies were 63.2% and 42% in group A, 65% and 65% in group B and 55.6% and 66.6% in group B1, respectively. From our preliminary results, we conclude that losartan is not superior to captopril renography for the detection of haemodynamically significant renal artery stenosis. However, a high dose (100 mg) of losartan provided higher sensitivity than the lower dose (50 mg). Late losartan scintigraphy provided similar diagnostic efficacy to early losartan renography.

An experimental study has been conducted to evaluate the effects of increased intra-abdominal pressure (IAP) on the excretion function from renal pelvis into the ureter.Sixteen adult male New Zealand rabbits were randomly allocated in two groups after obtaining basal scintigraphies. Group I consisted of 8 rabbits which were subjected to an increased IAP for ten day period. In Group II an other 8 rabbits were subjected to an increased IAP for 60 day period. At the end of the periods of increased IAP the post-pressure scintigraphic evaluations of both groups were carried out. Time to maximum activity (Tmax), T1/2 and T2/3 values of the radiopharmaceutical in the kidneys and down slope parameters (DS1/2, DS2/3) were calculated from the renogram curves of both right and left kidneys. Comparison of basal and post-pressure scintigrapies and the mean difference of the renogram parameters between groups were performed.All basal scintigraphies were normal. Post-pressure scintigraphies revealed an obvious delay in the excretion phase in both groups. Both kidneys of a rabbit in group I revealed a non-obstructive pattern through responding well to administration of diuretic. Furthermore both kidneys of a rabbit from group II have revealed an obstructive pattern. T1/2 and T2/3 values were significantly elevated and mean DS1/2, DS2/3 were significantly decreased in post-pressure scintigraphies of the both groups without revealing a statistically significant difference between groups I and II. The mean difference of Tmax was significantly increased in group II.The increases in IAP, through the compressive effect upon ureters together with a concomitant increase in intravesical pressure, may impair the passage of urine from renal pelvis into ureter. The impaired passage may play a role in the development of hydronephrosis which may either reveal a nonobstructive and/or obstructive pattern.

99mTc-Human immunoglobulin G ( 99m Tc-HIG) is a well-known radiopharmaceutical for the evaluation of inflammatory lesions. Recently, it has been demonstrated as a new agent for the visualization of the lymphatic system by our group. Our aim was to investigate the feasibility of detection of inflammatory lymph nodes by 99m Tc-HIG lymphoscintigraphy. Ten adult New Zealand rabbits were used as group A. In a baseline study, 37 MBq 99m Tc-HIG (0.1 ml) was injected into both hind legs of the rabbits, and sequential posterior gamma imaging with the rabbits lying prone was performed at 5, 15, 30, 60, 90 and 120 min using a single-headed gamma camera (Toshiba GCA G01 E). One week later, microorganisms (Staphylococcus aureus) were injected in a volume of 0.1 ml intradermally into the web space between the second and third toes in the bilateral hind legs of each rabbit in order to obtain inflammation in the popliteal lymph nodes. After 4 days, 37 MBq 99m Tc-HIG (0.1 ml) was injected into the hind legs of the rabbits bilaterally, and sequential posterior gamma imaging was performed as described above (second study). Another group of 10 adult New Zealand rabbits (group B) was injected with the same microorganisms in the right hind legs only. After 4 days, scintigraphic imaging was carried out in the same way as described above (third study). Regions of interest were drawn over the injection sites and popliteal lymph nodes on each image for semiquantitative analysis. Count rates for each were calculated and a decay correction was applied. Time-activity curves were generated to show the percentage retention of radioactivity in each region. After the scintigraphic study, some of the group B rabbits were killed by intravenous injection of pentobarbitone (100-150 mg.kg -1 , and both left and right lymph nodes were removed for microscopic examination. On the scintigrams, lymphatic channels and popliteal lymph nodes were visualized within 15 min. In the second study, bilateral popliteal lymph nodes were visualized more clearly than in the baseline study. The right popliteal lymph nodes of the rabbits were more clearly visualized in the third study. Semiquantitative analysis showed a higher percentage uptake of radioactivity in the right compared to the left popliteal lymph nodes in group B rabbits. Microscopic examination of the tissue sections demonstrated inflammation in the right lymph nodes of group B rabbits. In this preliminary study, it was found that 99m Tc-HIG is a new promising agent for the demonstration and evaluation of inflammatory lymph nodes.

A 24-year-old man whose clinical features were suggestive of renovascular hypertension was referred for captopril renal scintigraphy. Captopril renal scintigraphy was positive for renovascular hypertension only when the left kidney was analyzed in 2 separate regions. Angiography confirmed severe stenosis (90%) in the upper branch of the left renal artery.

Purpose Prostaglandins play important roles in renal physiology and in the development of renovascular hypertension. In a recent study, inhibition of renal prostaglandin synthesis was found to be useful for detecting renovascular hypertension using renal scintigraphy. In the current study, the authors evaluated the role of aspirin (an inhibitor of prostaglandin synthesis) and compared it with Tc-99m DTPA captopril renal scintigraphy (CS). Materials and methods Twenty-five patients were examined with Tc-99m DTPA in a three-step manner: a baseline study, CS, and aspirin scintigraphy (AS). Each scintigraphic study was interpreted visually and according to the renogram curve patterns. Semiquantitative parameters (Tmax, renal indices [%], 20-minute/max count ratio, glomerular filtration rate) were also calculated. Plasma renin activity was determined for each study. The blood pressures of all patients were measured during AS. All patients had a contrast-enhanced angiogram that was used as the reference test. Results Three groups of patients were observed based on the scintigraphic and angiographic results. In each group, no difference was observed in blood pressure after aspirin administration. In group 1, seven patients had normal angiographic and scintigraphic results. In group 2, eight patients had angiographically confirmed renal artery stenosis (RAS). In 6 patients (mean, 47% RAS), both AS and CS were negative for RVH. In the remaining two patients with RAS (mean, 83% stenosis), the kidneys were atrophic on the stenotic side, and thus the kidneys did not respond to the interventions. No difference was observed in plasma renin activity in groups 1 and 2. Group 3 included 10 patients who had angiographically confirmed RAS (mean, 86%). In 9 patients, both CS and AS were positive for RVH. In the remaining one patient, scintigraphic results were falsely negative. Statistical analyses performed for semiquantitative parameters did not reveal any significant difference in this group, although there was a tendency toward prolonged Tmax values after captopril and aspirin administration. In four cases, unexpected elevation of plasma renin activity was observed in group 3. Conclusions These data indicate that AS with Tc-99m DTPA is an alternative for CS. It has the advantage of having no effect on blood pressure and does not require that angiotensin-converting enzyme inhibitors be discontinued. Although in this study 9 of 10 patients had correct diagnoses of RAS, further studies, especially using tubular agents with the calculation of parenchymal transit time, might provide valuable information in this patient group. An ongoing study is being performed in the authors' institute.

Behçet's disease, initially described as local vasculitis involving the oral, genital mucosa and eyes, can affect many organ systems with a varying clinical course. Pulmonary lesions associated with Behçet's disease are rare and reported to have a prevalence of 1.0-7.7%. In this prospective study, 29 patients aged 16-60 years (mean +/- s: 34 +/- 10.5) were investigated for pulmonary involvement with direct radiography, computerized tomography (CT) and intravenous digital subtraction angiography. Lung scintigraphy was also performed to determine its diagnostic value. In addition, patients had a fibreoptic bronchoscopic examination, spirometric test, carbon monoxide diffusion test and methacholine test. Of the 29 patients with Behçet's disease, 17 had pulmonary involvement. The diagnostic criteria for pulmonary vasculitis and tracheobronchial tree involvement were: (1) hilar vascular prominence or mass, new alveolar and reticulonodular infiltrates on chest X-ray; (2) aphthous lesions, bleeding ulcerations, inflamed mucosal appearance on bronchoscopy; (3) vascular thrombosis or aneurysms on CT; (4) occlusion or aneurysms of the main pulmonary arteries or its branches. The value of lung scintigraphy and its correlation with other imaging modalities were investigated to determine if a lung perfusion scan alone can be used to detect pulmonary involvement in Behçet's disease. Twenty-six patients were investigated with lung scintigraphy. Thirteen of 14 patients with lung involvement were identified. Perfusion lung scintigraphy provided true diagnostic information in 96% of our patients. In eight patients without pulmonary involvement, the lung scans were normal. Although DSA specifically demonstrates pulmonary aneurysms, it involves administration of contrast media and cannot show abnormalities distal to the third pulmonary arterial branches. Although vasculitis caused by collagen disorders is physiologically indistinguishable from pulmonary emboli, most perfusion defects resolve within 3 months, which can be used as a differential diagnostic criterion in the appropriate clinical setting. Therefore, pulmonary perfusion imaging can be used to screen patients suspected of having lung involvement, especially in the absence of thrombophlebitis. In patients with thrombophlebitis, a repeat examination at 3 months is recommended to differentiate pulmonary involvement from pulmonary embolism.

In this pilot study, 99 Tc m -labelled human immunoglobulin G ( 99 Tc m -HIG) was evaluated as a lymphoscintigraphic agent in five rabbits. It was injected intradermally into the web space of the hind legs of the rabbits (37 MBq/0.1 ml). Sequential scintigrams were obtained using a gamma camera for 120 min. The injection site and the hind legs were massaged post-injection. Blood samples were obtained at 5, 15, 30, 60, 90 and 120 min. Two of the rabbits were killed after 2 h. Their organs were weighed and tissue specimens were obtained, weighed and counted against a standard using a gamma counter. The lymph channels and the lymph nodes were well visualized on the scintigrams. The background activity was very low, making interpretation easier. About 30% of the injected dose migrated from the injection site by 2 h. The mean popliteal lymph node uptake was 5.71± 4.62% per gram of tissue. The lymph node to other tissue concentration ratios were very high, ranging from 63:1 for the kidneys to 1099:1 for the heart. We conclude that 99 Tc m -HIG is a promising new agent for the visualization of the lymphatic system due to its easy labelling procedure, the stability of the label, its widespread availability and good image quality. It may potentially be useful in detecting and evaluating inflammatory lymph nodes.

In the light of recent advances in radionuclide diagnostics of occult infectious states, it is clearly seen that positron emission tomography will have a part in routine work-up especially for critically ill patients in near future. For the purpose of further development of a specific agent that might be capable of detecting a living microorganism in occult focus inside the host organism, we come with a concept of probably a new radiopharmaceutical agent besides well-known fluorinated glucose, labelled leucocytes and gallium based radiopharmaceuticals. The aim of this opinion letter is to propose a specific agent for almost all bacteria and fungi genera not depending on host’s metabolism, thus letting differentiation of infection foci from host’s tissue. The discussion of this letter is mainly on the background of developing a compound for folate biosynthesis in bacteria and fungi which is a specific way of metabolization by the mentioned species which is provided by microbiological studies.

In dacrystic seizures lacrimation has previously been reported as an ictal autonomic event accompanying emotional and somatic signs. However, it has not been observed as an isolated event in autonomic seizures. We report a patient experiencing complex partial seizures characterized by lacrimation as the initial and most prominent ictal event, with no sign of crying. The patient’s ictal electroencephalogram (EEG) suggested a focus in the right hemisphere, along with interictal single-photon emission computed tomographic (SPECT) and positron emission tomographic (PET) studies demonstrating hypoperfusion-hypometabolism in the right temporoparietal lobe. Magnetic resonance imaging (MRI) did not show any structural abnormalities. Involvement of the temporal lobe has been suggested for dacrystic seizures, and both dominant and nondominant hemispheric foci were detected in such cases. Therefore, partially in concordance with previous reports, our case may point to neurobiologic interaction, between the temporoparietal region and the hypothalamus, for mediating lacrimation.

RATIONALE AND OBJECTIVES The authors present preliminary findings on the diagnosis of renovascular hypertension with technetium-99m-ethylenedicysteine (99mTc-EC). METHODS Thirty-nine patients referred to the nuclear medicine department with clinical evidence of renovascular hypertension were included in the study. Baseline and captopril scintigraphies were done on separate days after the injection of 185 MBq of 99mTc-EC. All patients had angiographic correlation and 9 patients were shown to have renal artery stenosis. RESULTS Quantitative analysis of the data showed no significant changes of perfusion index (PI), split renal function (SRF), and effective renal plasma flow (ERPF) values between pre- and postcaptopril studies in patients with significant renal artery stenosis (P > 0.05). Baseline and postcaptopril values for PI, SRF, and ERPF were measured as 128 +/- 21 and 116 +/- 12 mL/minute, 47 +/- 1 and 50 +/- 2 mL/minute, and 250 +/- 18 and 231 +/- 20 mL/minute, respectively. However, time to maximum activity (Tmax), time to half maximum activity (T 1/2), time to two thirds of maximum activity (T 2/3), and residual cortical activity (RCA) values showed marked changes with a rising renogram curve (P < 0.05). Baseline and postcaptopril values for Tmax, T 1/2, T 2/3, and RCA were measured as 3.1 +/- 0.1 and 20.2 +/- 1 minute, 5.4 +/- 0.4 and 45.4 +/- 3.1 minutes, 3.1 +/- 0.2 and 33.7 +/- 4.1 minutes, and 27 +/- 4 and 215 +/- 34 minutes, respectively. All scintigraphic studies showed good correlation with angiography and no false-positive or false-negative results were observed. CONCLUSIONS This preliminary study demonstrates that 99mTc-EC has good potential for the diagnosis of renovascular hypertension and that a single diagnostic criteria, specifically a rising renogram curve, seems adequate. However, the authors' initial results should be confirmed in a broader patient population.

Technetium-99m-ethylenedicysteine (99mTc-EC) captopril scintigraphy performed in a patient with severe hypertension revealed increased parenchymal retention in the left kidney, suggesting renal artery stenosis. After angiographic confirmation of renal artery stenosis, percutaneous transluminal angioplasty (PTA) was performed on the left renal artery. Captopril scintigraphy after PTA showed normal findings with no evidence of parenchymal retention, consistent with reversal to normal kidney functions. In light of this case of renal artery stenosis, it was concluded that 99mTc-EC can be used successfully as a potential renal agent in the diagnosis and follow-up of renovascular hypertension.

Genotype/allele distributions of leptin promoter G-2548A polymorphism, serum leptin and insulin levels and body weight were not significantly different between 72 children (39 male/33 female; age range 1.08-16, median 6 years) with acute leukemia (56 acute lymphoblastic leukemia [ALL]/16 acute non-lymphoblastic leukemia [ANLL]) at diagnosis and 70 age- and sex-matched controls (p0.05). The - 2548GG genotype was associated with the highest leptin levels in controls and patients with acute leukemia after 7-day high-dose methylprednisolone (HDMP) therapy (p0.05), while no significant association of genotype with leptin levels was detected in patients at diagnosis (p0.05). One-week HDMP therapy in patients carrying the - 2548G allele caused a significant increase in leptin levels and body weight (p0.001), whereas increases in those carrying the - 2548AA genotype were insignificant (p0.05). Decreases in white blood cell counts of patients after therapy were insignificant in - 2548GG (p0.05) yet significant in - 2548GA and - 2548AA (p0.05) genotypes. These results revealed no association of leptin genotype with the etiology of childhood acute leukemia but a possible association with leptin levels and effects of HDMP therapy.

Some patients with pervasive developmental disorders develop unusual talents, which are characterized as savant syndrome. Herein we present neuropsychological examination and brain imaging (fMRI and brain SPECT) findings of an 18-year-old male with Asperger syndrome and highly unusual calendar memory. Neuropsychological evaluation of the case indicated mild attention, memory, and problem solving deficits, and severe executive function deficits that included conceptualization, category formation, and abstraction. Functional MRI findings showed activation above the baseline level (P0.05) in the bilateral inferior parietal lobule, precuneus, superior and middle frontal gyri, and medial frontal cortex. Brain SPECT findings, in comparison to rest-SPECT findings, showed that there was hypoperfusion in some brain regions, including the right frontal cortex and right parietal cortex. Baseline blood perfusion in the left frontal cortex was also observed, as well as hypoperfusion in the right parietal-occipital cortex and in the right basal ganglion (compared to the left side). The results of the present study and further research will contribute to our understanding of calendar memory and savant syndrome.

Subtraction ictal single photon emission tomography (SPET) co-registered to magnetic resonance imaging (SISCOM) is an ictal-interictal brain perfusion SPET subtraction method, developed for evaluation of brain perfusion changes applied for the identification of epileptic foci. The aim of this study was to test whether regional cerebral blood flow (rCBF) alterations due to clozapine in schizophrenic patients could also be detected with SISCOM. We have studied the brain perfusion SPET data obtained both before (pre-SPET) and 8 weeks after (post-SPET) clozapine treatment, in 20 patients with schizophrenia. These data were used for SISCOM processing. In order to identify any alterations in the perfusion pattern using SISCOM, pre- and post-SPET data were subtracted from each other. Activation maps were created and merged on either pre- or post-SPET images. Visual interpretation of brain perfusion SPET studies were performed and compared with SISCOM findings. We found that final SISCOM images and visual evaluation of pre- and post-SPET studies were well concordant in 17/20 patients. Discordance was observed in 3 patients. In 1 of these 3 patients alterations observed with SISCOM were confirmed as subtle changes on visual re-evaluation of the images. In the remaining 2 of these 3 patients, SISCOM did not confirm the changes observed by visual analysis. Additionally, SISCOM depicted perfusion alteration in occipital cortex in 5 patients. In conclusion, the algorithm of SISCOM seemed to be useful and complementary to visual evaluation, to assess rCBF changes due to clopazine in outpatient schizophrenic patients who had treatment refractoriness or intolerance of previous antipsychotics and to provide additional information when both pre- and post-SPET data were subtracted from each other.

Conversion disorder is defined as the presence of functional impairment in motor, sensory or neurovegetative systems which cannot be explained by a general medical condition. Although the diagnostic systems emphasize the absence of an organic basis for the dysfunction in conversion disorder, there has been a growing interest in the specific functional brain correlates of conversion symptoms in recent years, particularly by examining neuroimaging and neurophysiological measures. In this case report, regional cerebral blood flow changes and evoked potentials of a patient with conversion symptoms are presented. Somatosensory evoked potentials (SEP) of this patient with conversion disorder who had signs of movement disorder revealed that the latency to N20, P 25 waves were in normal limits while the amplitudes of the P25 and N33 components were extremely high (giant SEP). Regional cerebral blood flow assessment revealed hypoperfusion in the left parietal and temporal lobes of the brain. Three months after the first assessment, the control scans showed that the left parietal hypoperfusion disappeared while the left temporal hypoperfusion was still present. The following SEP evaluations which were repeated twice in three months intervals after the initial recordings, showed the persistence of the abnormalities in somatosensorial measures. The neurophysiological and neuroimaging findings in conversion disorder were reviewed and the results of the evaluations of this case were discussed in this article.

The authors describe the incidence and various uptake patterns of Tc-99m sestamibi (MIBI) in the extracardiac area due to unusual causes on myocardial perfusion single photon emission computed tomography (SPECT) studies. Seven patients are presented in whom incidental extracardiac findings were observed during the interpretation of the raw data besides the routine evaluation of myocardial reconstructed SPECT slices. These 7 patients were detected out of 582 consecutive patients (1.2%) who had myocardial perfusion SPECT with Tc-99m MIBI. The findings on the raw data led to additional reconstruction of thoracic SPECT images and eventually detailed examination of the extracardiac area. Two of the patients underwent surgery because of incidental extracardiac findings (thymoma and multinodular goiter) on cardiac scintigraphy. Other causes of increased extracardiac activity were the intestine protruded through the left hemithorax, uptake in the pulmonary arterial wall, and pulmonary interstitial fibrosis due to sarcoidosis. The reasons for decreased Tc-99m MIBI accumulation in the extracardiac area in the 2 other patients were significantly dilated pulmonary arteries and hydatic cyst, which were not defined before to our knowledge. Familiarity with the normal biodistribution and variable uptake patterns in the raw images becomes necessary during the interpretation of myocardial SPECT in order not to miss very unusual incidental extracardiac uptake or information that could lead to alteration in patient management. Potential underlying mechanisms of extracardiac Tc-99m MIBI accumulation are discussed, and the literature about noncardiac Tc-99m MIBI findings detected on myocardial perfusion SPECT studies was reviewed.

The purpose of this study was to investigate the effect of clozapine on regional cerebral blood flow (rCBF) and its relationship with response to treatment. In addition, we aimed to study the influence of clozapine on proton magnetic resonance spectroscopy (H-1-MRS) findings in the dorsolateral prefrontal cortex (DLPFC) in a subgroup of patients. Psychopathology, neurocognitive functioning, and SPELT imaging of 22 patients were assessed at the baseline and 8 weeks after the initiation of clozapine treatment. In 10 of these patients intermediate-echo (TE: 135 ms) single-voxel H-1-MRS was also performed at the baseline and after 8 weeks. Clozapine treatment increased the right frontal (superior and medial)/caudate perfusion ratio in the whole group, while it increased bilateral frontal (superior and medial)/caudate perfusion ratios in treatment responders. In addition, percentage changes in left and right frontal (superior and medial)/caudate perfusion ratios compared to the baseline were higher in treatment responders than in non-responders. The improvement in attention was related to the increase in percentage change in the right frontal (superior and medial)/caudate perfusion ratio, while the improvement in verbal fluency was related to the increase in percentage changes in both right and left frontal (superior and medial)/caudate perfusion ratios and to right frontal (superior and medial)/thalamus perfusion. Baseline frontal (superior and medial)/thalamus perfusion could explain 32% of the variability of percentage improvements in psychopathology. H-1-MRS showed that the baseline PANSS general psychopathology score was inversely correlated with the baseline NAA/Cre ratio. An increased NAA/Cre ratio in DLPFC after 8 weeks of clozapine treatment was also revealed by H-1-MRS. Our SPELT imaging results suggest the presence of an imbalance in fronto-striato-thalamic circuitry that changes with clozapine, especially in the responders, while H-1-MRS results indicate a supportive effect of clozapine on neuronal integrity. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

To define the role of Tc-99m (V) dimercaptosuccinic acid (DMSA) scanning in the detection of lung cancer (LC) and its metastases, and monitoring the response of LC lesions (LCL) to chemo/radiotherapy (TH).Tc-99m (V) DMSA whole-body scans, planar thorax views, and thorax Single-photon emission computed tomography (SPECT) images were obtained both 30 min (early) and 5 h (late) after Tc-99m (V) DMSA administration in 12 small/nonsmall cell LC patients (11 men, 1 woman; mean age 59 years). Five patients also had bone scans. The same scintigraphic protocol was performed in 7 of 12 patients, 3 weeks after first-line TH. TH response was evaluated visually in all LCL and semiquantitatively in primary tumors (PT) of six patients, by comparing the tumor uptake ratios (TUR) of pre-TH and post-TH Tc-99m (V) DMSA SPECT [TUR = mean counts of region of interests (ROI) in PT/mean counts in contralateral ROI]. In seven patients, a 6-month survival was determined.Tc-99m (V) DMSA accumulated in 34 LCL (11 PT, 19 bone metastases, 1 suprarenal mass, 1 axillary node, 2 supraclavicular nodes). A total of 11 patients displayed Tc-99m (V) DMSA uptake in LCL and one patient did not show uptake. In six patients, SPECT imaging showed deeply located PT in the lung parenchyma better than planar views. In five patients, both planar and SPECT views revealed peripherally located PT in the lungs. Early scans showed 18 LCL and late scans displayed all the LCL. Nine bone metastases on pre-TH Tc-99m (V) DMSA scans revealed matched areas of increased Tc-99m methylene diphosphonate (MDP) uptake on bone scans; six bone metastases were additionally detected on Tc-99m (V) DMSA scans when compared with bone scans, and four bone metastases on Tc-99m (V) DMSA scans could not be compared with bone scans because bone scan was not performed. In one patient, Tc-99m (V) DMSA scans became positive for bone metastases on post-TH later than the bone scans for some of the bone metastases. Neither planar nor SPECT imaging showed mediastinal lesions defined on thorax CT in nine patients. On TH monitoring, 17 LCL showed diminished Tc-99m (V) DMSA uptake, one disappeared, four were unchanged, three displayed increased uptake, and five new lesions were established. Of the six patients, TUR in PT increased in two (one survived), decreased in one (exitus), was unchanged in two (two exitus) on post-TH scans, and PT totally disappeared in one (survived) patient.Tc-99m (V) DMSA scans are useful in detecting LCL, except for those around the blood pool regions, making it a promising modality to monitor TH response. Obtaining a single fifth hour late Tc-99m (V) DMSA scan is appropriate. SPECT should be applied to all patients for the detection of deeply located lesions.

In addition to well-known specific conditions for soft-tissue uptake of bone-seeking radiotracers, there is a limited number of reports on intestinal uptake of (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) on bone scans.To describe the incidence of intestinal accumulation of (99m)Tc-MDP on bone scans in adult patients, define the patterns of this unusual finding and review the literature on its causes.Two thousand, one hundred and forty-four consecutive patients have been evaluated for intestinal (99m)Tc-MDP uptake on bone scans. Intestinal uptake was observed visually 3-4 h after the administration of the radiopharmaceutical. A whole-body bone scan and various spot views of the abdomino-pelvic region were obtained with a dual-headed gamma camera to evaluate the intestinal uptake. Delayed scans were also obtained as well as co-relative imaging and/or colonoscopic studies in some of intestinal uptake patients. Six patients had delayed scans of the abdomino-pelvic region. Fourteen patients had comparable scans either a year before or a year later. The positive intestinal uptake scans were further grouped according to the localization and intensity (mild uptake: lower than iliac bone; moderate uptake: equal to iliac bone; significant uptake: higher than iliac bone).Twenty-two (17 female, five male) patients out of 2144 with a mean age of 57 years showed intestinal (99m)Tc-MDP uptake. The localization was mainly (20/22) in the right abdomino-pelvic region projecting on and in the configuration of ascending colon while one patient showed intestinal uptake all over the abdomen and one displayed diffuse intestinal radioactivity in his right hemithorax. The majority of the cases showed moderate to intense intestinal uptake (18/22). Six patients showed a decrease, disappearance or alteration in the intestinal uptake on the delayed images. Re-evaluation bone scans in five patients 1 year later showed no intestinal uptake this time. Among nine patients with prior bone scans 1 year before, intestinal uptake was negative in seven at that time. No significant pathology was obtained on the correlative images.(99m)Tc-MDP uptake can be observed in the intestines in 1% of bone scans with a prominent localization in the ascending colon and rarely all over the intestines or in thorax due to Chilaiditi's syndrome, as well. The mechanism of intestinal uptake is still unclear in some of the patients. Delayed imaging, additional spot views and SPECT studies help in the differentiation of this finding from possible misinterpretation. Intestinal (99m)Tc-MDP uptake on bone scan could be an intermittent process and should be included among other well-known reasons of soft-tissue uptake.

Periodic lateralized epileptiform discharges (PLEDs), which are known as unusual electroencephalogram (EEG) patterns, are described in a patient who had stroke and seizures. This patient underwent Tc-99m HMPAO (hexamethyl propylene amine oxime) brain single photon emission computed tomography (SPECT) imaging both during PLEDs on EEG and after the cessation of PLEDs. The initial SPECT study revealed increased CBF in the left frontal and parietal cortex extending through the left temporal region and in the left basal ganglium. After the PLEDs disappeared, the second SPECT study showed decreased perfusion on the left frontal and parietal region in the brain. Brain SPECT findings supported the contention that PLEDs may be an ictal phenomenon. Here we also present a review on PLEDs and contributions of brain SPECT as a functional imaging modality to investigate the underlying mechanism of this interesting EEG pattern.

This report describes a pediatric patient with cholecystectomy, excision of type 1 choledochal cyst, and Roux-en-y hepatojejunostomy in whom hepatobiliary scintigraphy played an important role to find out the reason of her postoperative symptoms, helped her surgeons to make the postoperative diagnosis as ascending cholangitis, and plan the patient's secondary therapy.

Background Subtraction of ictal and interictal single photon emission computed tomography (SPECT) images is known to be successful in localizing the seizure focus in the pre-surgical evaluation of patients with partial epilepsy. A computer-aided methods for producing subtraction ictal SPECT co-registered to the magnetic resonance image (MRI) (the SISCOM method) is commonly used. The two registrations involved in SISCOM are (1) between the ictal-interictal SPECT images, which was shown to be the more critical, and (2) between the ictal image and MRI. Objective To improve the accuracy of ictal-interictal registration in SISCOM by registering all three images (ictal, interictal SPECT, MRI) simultaneously. Methods The registration problem is formulated as the minimization of a cost function between three surfaces. Then, to achieve a global minimum of this cost function, the Powell algorithm with randomly distributed initial configurations is used. This technique is tested by a realistic simulation study, a phantom study and a patient study. Results The results of the simulation study demonstrate that, in surface-based registration, the triple-registration method results in a smaller ictal-interictal SPECT registration error than the pair-wise registration method (P

SummaryA sequential 99mTc-MAG3 renogram of a 20-year-old male who received a kidney from a living related donor is presented. Pre-transplant angiography of the donor showed the kidney had a single renal artery with upper and lower branches. The transplantation procedure was uneventful, allowing rapid simultaneous perfusion to the entire kidney. The first scan performed 2 days after the transplantation was normal except for retention of the radiotracer at the upper pole of the kidney. The renal collecting system was normal and no signs of dilatation or obstruction were noticed on ultrasonographic examination. A follow-up scan done on the 5th day of transplantation showed almost complete evacuation of the parenchymal retention previously seen on the upper pole of the kidney. This unusual finding was consistent with segmental acute tubular necrosis (ATN) of the upper pole of the kidney and showed that ATN might involve only a portion of a kidney in spite of the existence of a single artery of the transplant.

Poorly differentiated insular thyroid carcinoma is classified as a separate entity among other tumors of the thyroid gland. Its histological pattern and clinical course are regarded as intermediate between well-differentiated and anaplastic thyroid cancer. The authors report Tc-99m pertechnetate, Tc-99m MDP and radioiodine imaging features in a 33-year-old male patient with metastatic insular carcinoma of the thyroid. The extent of involvement was almost identical in all three studies. Insular carcinoma of the thyroid was shown by biopsy, and the patient received a cumulative dose of 14,800 MBq (400 mCi) radioactive 1–131. Other radionuclide imaging agents are also reviewed.

Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG) has been successfully used in the evaluation of a variety of malignancies. This work reports a 76-year-old man with a history of small cell carcinoma of the parotid gland, a rare tumor. The tumor was surgically resected.

The authors describe various patterns of F-18 fluorodeoxyglucose (FDG) accumulation in the diaphragm and crura. They present 6 patients in whom incidental diaphragmatic and crural uptake of FDG was observed during positron emission tomography (PET). Hyperventilation is thought to be the potential underlying mechanism of this condition.

The most common indication for radionuclide imaging of lungs is the evaluation of suspected pulmonary thromboembolism (PE). Scintigraphically PE classically produces ventilation/perfusion mismatch, that is perfusion defects in areas showing normal ventilation. Stripe sign refers to the visualization a stripe at normally perfused lung interposed between a defect and adjacent pleural surfaces as originally described by Gottschalk. In the present case the authors describe a patient with a ventilation/perfusion scan suggesting PE. She also had a stripe sign on the perfusion scan with normal ventilation. On the follow-up perfusion scintigraphy, normal perfusion was seen in the corresponding area. The literature on stripe sign is also reviewed.

Gastrointestinal stromal tumors (GISTs) comprise the category of nonepithelial neoplasms that arise in the wall of the stomach, small intestine, colon, and other sites within the abdominal cavity. The authors describe a patient with recurrence of GIST in the small bowel that showed significant fluorodeoxyglucose (FDG) uptake and in whom FDG-positron emission tomographic (PET) imaging played an important role in treatment planning. The case reported here emphasizes that FDG-PET imaging may have an important role in the staging, restaging, and post-therapy follow-up of GIST, a rare type of tumor.

A 5-year-old boy with an abnormality of chromosome 14 was referred to our department for the evaluation of vesicoureteral reflux. Indirect radionuclide cystography including renal scintigraphy was performed. In the case presented here, the location of the ectopic right kidney was demonstrated with indirect radionuclide cystography in a child with high-grade vesicoureteral reflux.

The aim of the study was to compare late and early onset alcoholism with regard to regional cerebral blood flow (rCBF) and neuropsychological functioning. Ten late onset and 13 early onset male alcoholics were included in the study, the criterion being the age of onset for alcohol abuse. Six healthy male volunteers were included as a control group. Regional measures of cortical cerebral blood flow were assessed using Tc-99m-HMPAO single photon emission computed tomography (SPECT) after a detoxification period. When compared with the control group, the early onset group showed reduced relative perfusion in the left superior frontal region, while relative perfusion in the late onset group was deficient in both right and left superior frontal regions. Both groups of alcoholic patients also displayed impairment in frontal lobe functions and non-verbal memory. The results of this study indicate that early onset alcoholism is associated with hypoperfusion in the left superior frontal region while the late onset subtype is characterized by uniformly hypoperfused left and right superior frontal regions. Additionally, both groups of alcoholic patients exhibit an almost identical pattern of neuropsychological abnormalities mainly related to frontal lobe functions and non-verbal memory. Collectively these findings support previous evidence suggesting a key role of frontal lobe pathology in understanding the neurobiology of alcoholism.

Radioembolization is used in diagnostic imaging of the lungs and for radioembolization therapy of hepatic tumours. Presently, 99mTc labelled macroaggregates or microspheres of human serum albumin (HAM) are used for this purpose. Poly lactic acid (PLA) is biodegradable, like HAM, and, unlike HAM, is not a blood product. The aim of the present study was to evaluate the uptake and biodegradation of PLA microspheres in lungs. PLA (MW = 48720 Da) microspheres of 1.0-100 microm (mean = 39.5 microm) in diameter were prepared by solvent evaporation from methylene chloride. They were labelled with 99mTc by stannous chloride reduction at pH 3, with an efficiency of 98% and a stability of 96% at 24 h. For biodistribution studies, 15 mice were i.v. injected with 20 microCi 99mTc-PLA microspheres in 0.1 ml and sacrificed at 15 min, 1, 3, 6 and 24 h (three at each time point). All the organs were removed, weighed and counted against a standard prepared from 1/100 dilution of the injected radioactivity. Some mice were similarly injected and sacrificed at 30 min, 15 and 30 days. The lungs were removed and frozen, and 10 microm sections were obtained, stained with haemotoxylin and eosin and examined under a light microscope. Five rabbits were i.v. injected with 1 mCi of 99mTc-PLA microspheres. Scintigrams were obtained at various intervals up to 24 h. In mice, the lung uptake was significant at 30 min-1h post-injection. In rabbits, the lungs were the only organs visualized up to 24 h. Microscopic examination of tissue sections demonstrated slow biodegradation of PLA particles. In conclusion; (1) The high lung uptake obtained in mice and rabbits indicates the suitability of PLA microspheres for lung imaging, and (2) although the slow biodegradation rate might be a disadvantage in patients with lung disorders in diagnostic studies, it may be an advantage in therapeutic applications with radionuclides which have long physical half lives.

I read with great interest the letter to the editor by Georgoulias et al., published in the January 2009 issue concerning the drug enhancement of myocardial tracer uptake during myocardial perfusion imaging [1]. The authors also focused on our article “Tc sestamibi myocardial perfusion scintigraphy (MPS) with the novel use of metamizol for the detection of perfusion reversibility” published in the August 2008 issue [2]. Metamizol has been in clinical use for more than three quarters of a century, and recent reports have shown that metamizol also has a relaxing activity in vascular smooth muscle as assessed in in vitro tissue bath techniques and in vivo animal models [3–8]. In our above-mentioned study [2], we aimed to investigate whether the vascular smooth muscle relaxing effect of metamizol has the potential to better define myocardial ischaemia during MPS and we found that metamizol rest MPS displayed the defect reversibility better than baseline rest MPS and that metamizol-induced myocardial sestamibi uptake was significantly higher (p

Although, captopril scintigraphy is a well established method to detect renovascular hypertension, the optimal radiopharmaceutical for this test remains to be determined. Recently, Tc-99m ethylenedicysteine (Tc-99m EC) appeared as an alternative agent for captopril scintigraphy. The aim of this study was to compare the diagnostic accuracy of Tc-99m EC with Tc-99m DTPA, which is a well-established renal radiopharmaceutical for the captopril test.Nineteen hypertensive patients who had various degrees of renal artery stenosis on angiography were included in the study. All patients had baseline and captopril Tc-99m EC and Tc-99m DTPA scintigraphy within a 1-week period. The results were compared with angiography and in eight patients with changes in blood pressure after revascularization. The images were interpreted without knowledge of the angiography and revascularization data as low, intermediate, or high probability for hemodynamically significant renal artery stenosis, which was defined as an area of stenosis exceeding 50%.Tc-99m EC and Tc-99m DTPA study results were in agreement in 16 of the 19 patients. In two patients with branch artery stenosis, Tc-99m EC was definitely superior to Tc-99m DTPA and correctly identified the probability of stenosis on scintigraphy. On kidney analysis, Tc-99m EC had a slightly greater diagnostic sensitivity compared with Tc-99m DTPA (79% vs. 68%; P0.05 by the chi-squared test) but equal specificity (93% for both agents). Both Tc-99m EC and Tc-99m DTPA showed the same accuracy in predicting the outcome after revascularization in all but one patient with branch artery stenosis, in whom Tc-99m EC accurately predicted a successful outcome of the intervention but Tc-99m DTPA did not. Tc-99m EC had better renal uptake in patients with decreased renal function and provided more dramatic evidence of renogram changes after captopril intervention, which resulted in more confident interpretation.There is no significant difference between Tc-99m EC and Tc-99m DTPA captopril scintigraphy for detecting renal artery stenosis. However, because of the better imaging characteristics and more confident interpretation provided by the dramatic changes in the degree of renogram abnormality after captopril intervention, Tc-99m EC captopril scintigraphy should be used, particularly in patients with decreased renal function or branch artery stenosis.

The aim of the present study was to assess the predictive value of captopril scintigraphy with the new renal agent 99mTc-ethylenedicysteine (99mTc-EC) for post-interventional improvement in blood pressure. Twelve patients who had persistently high blood pressure with previous demonstration of various degrees of renal artery lesion on angiography were included into the study. Baseline and captopril scintigraphies were performed on the same day at 4 hour intervals after the injection of 74 and 296 MBq of 99mTc-EC, respectively. All patients had percutaneous transluminal angioplasty (PTA), and improvement in blood pressure was evaluated 3-6 months after the intervention. 99mTc-EC captopril scintigraphy successfully predicted a positive or negative outcome in 11 of 12 patients. In one patient with captopril induced renal function deterioration, scintigraphy failed to predict post-interventional response. Our preliminary findings showed that 99mTc-EC captopril scintigraphy can be used to determine patients who will benefit from revascularization.