Tamer Atasever

Evaluation of malignant and benign lung lesions with 99Tcm-tetrofosmin.

Summary99Tcm-tetrofosmin planar imaging was performed in 30 patients with malignant and benign lung lesions. There were 21 cases of primary lung cancer (10 squamous cell, 5 small cell, 4 adenocarcinoma and 2 large cell) and 9 benign lung lesions (4 pneumonia, 3 tuberculosis, 1 infected bronchiectasis and 1 bronchiolitis obliterans). Anterior and posterior planar thorax images were obtained 30 min after the intravenous injection of 740 MBq (20 mCi) of 99Tcm-tetrofosmin. Visual and quantitative evaluations were performed. For the quantitative evaluation, regions of interest were drawn over the lesioned area (L) and over the contralateral non-lesioned area (N). Of 21 malignant primary lesions, 19 (90%) showed 99Tcm-tetrofosmin accumulation. Four (44%) of the nine benign lung lesions (3 cases of pneumonia and the one case of active tuberculosis) showed uptake. The mean L/N ratios for the malignant and benign lesions were 1.63 ± 0.29 and 1.64 ± 0.19, respectively. There were no significant differences (P > 0.05) in the L/N ratios of the malignant and benign lesions or the various histological types of cancer. In conclusion, 99Tcm-tetrofosmin was highly sensitive (90%) in detecting malignant lung lesions, but it had poor specificity (55%).

Comparison of three different diuretic renal scintigraphy protocols in patients with dilated upper urinary tracts.

Purpose: To compare 3 different diuretic renal scintigraphy protocols in patients with dilated upper urinary tract. Materials and Methods: Three diuresis renography protocols were performed in 22 adult patients (28 kidneys) with upper urinary tract dilatation. The diuretic was given 20 minutes after (F+20), at the same time as (F+0), and 15 minutes before (F−15) radionuclide administration. The mean age was 29.8 years (range, 18–43 years). The 3 protocols were identical, except for the time of injection of furosemide. The F+0 protocol could not be performed in 1 and F−15 in 2 of the patients. Each of the 3 protocols was performed for the rest of the patients. The results were classified as nonobstructive, equivocal, and obstructive according to the renogram images and curves. Results: None of the patients showed equivocal results in both F+0 and F−15 protocols. In the F+20 studies, 7 of the 28 kidneys were evaluated as equivocal. Of these, 5 kidneys showed nonobstructive and 2 kidneys revealed obstructive renogram patterns with the other 2 protocols (F+0 and F−15). Moreover, one kidney, which was evaluated as nonobstructive in the F+20 protocol, showed an obstructive pattern in both F+0 and F−15 protocols. All of the kidneys showing obstructive patterns in the F+20 study also revealed obstruction in the F+0 and F−15 investigations. We could not find any difference between the renogram patterns of F+0 and F-15 investigations. Conclusions: F+0 and F−15 protocols allow clarification in cases of equivocal F+20 studies. Because the F+0 study is more practical and shorter, we suggest the F+0 method when equivocal results are obtained by an F+20 study or as a single test when there is only one opportunity to confirm or exclude the presence of obstruction.

Value of bone scintigraphy in patients with carpal trauma.

ObjectiveWe planned this study to evaluate the role of bone scintigraphy in patients with suspected carpal fracture and normal or suspicious radiographs following carpal injury.MethodsThree-phase bone scintigraphy using Tc-99m-MDP was performed on 32 patients with negative radiographs but clinically suspected fracture at two weeks after the trauma. Focally increased radiophar-maceutical uptake was interpreted as a fracture. The final diagnosis was established with clinical follow-up.ResultsTwelve (38%) patients had a normal scan excluding fracture. Twelve patients had a single fracture. Multifocal fracture was present in 8 (25%) patients. Eight patients showed scaphoid fractures; of these three showed single scaphoid fracture, and the other five patients revealed accompanying fractures. Distal radius fractures and carpal bone fractures other than scaphoid were both observed in 12 patients. These were eleven fractures of distal radius; three fractures of pisiform; two fractures of hamate; and single fractures of lunate, trapezium and triquetrum. In one patient there was fracture of a first metacarpal bone.ConclusionIn patients with suspected carpal bone fracture and normal or suspicious radiographs, bone scintigraphy can be used as a reliable method to confirm or exclude the presence of a scaphoid fracture and to detect clinically unsuspected fractures of distal radius and other carpal bones.

TL-201 scintigraphy, mammography and ultrasonography in the evaluation of palpable and nonpalpable breast lesions: a correlative study☆

PURPOSE To determine the feasibility of Tl-201 as a tumor localizing agent in palpable and nonpalpable breast lesions, in comparison with mammography and ultrasonography (US), and to evaluate the contribution of these modalities to each other in obviating biopsy. MATERIALS AND METHODS Seventy-two palpable and nonpalpable breast lesions were prospectively classified as benign, indeterminate, or malignant according to the sonographic and mammographic criteria and were further analyzed with Tl-201 scanning. These classifications were compared with biopsy results. The sensitivity, specificity, accuracy, false positive and false negative rates (FPR, FNR), negative and positive predictive values (npv, ppv) were calculated for each individual modality and combination of modalities to evaluate the contribution of these three techniques to each other. RESULTS Of 72 lesions 52 were histologically malignant and 20 were benign. Overall, mammography was the most sensitive (92%) and Tl-201 was the most specific (75%) of the three modalities. Mammography + Tl combination was the most specific (90%) and accurate (97%) of dual combinations. In mammographically or sonographically indeterminate cases, Tl-201 was much more specific (75% versus 37% for mammography and US) and more accurate (82% versus 36% for mammography and 54% for US) than the other two modalities, and mammography + Tl combination was significantly superior to other dual combinations (87% specific and 91% accurate). Use of Tl-201 scanning as an adjunct to mammography + US combination increased the specificity, ppv, and accuracy rates overall, particularly in mammographically or sonographically indeterminate cases. CONCLUSIONS In mammographically and sonographically indeterminate breast lesions thallium scanning may be offered as a third step of investigation to obviate biopsy.

Gastric Emptying in Patients on Renal Replacement Therapy

In addition to gastrointestinal tract symptoms such as nausea, vomiting, and loss of appetite, impaired gastric emptying time (GET) may be related to nutritional parameters and nutritional status of patients on renal replacement therapy (RRT). Patients on RRT are affected by several factors such as uremic toxins, the presence of dialysate in the peritoneal cavity, and the drugs used against renal allograft rejection. In this study, we investigated the gastric emptying time and its relationship with biochemical and nutritional parameters in patients on RRT: those on hemodialysis and peritoneal dialysis, and renal transplantation patients. Seventy‐five patients, 44 on hemodialysis, 16 on peritoneal dialysis, and 15 renal transplant patients, were included in the study. They were examined for gastric emptying time using a radioisotopic method. The results were compared with the GET of healthy subjects. Each group of patients was evaluated in terms of hemoglobin, hematocrit, blood urea nitrogen (BUN), creatinine, blood glucose, total protein, albumin, serum lipids, parathyroid hormone (PTH) and body mass index and biceps and triceps skinfold. The mean GET of patients on RRT was significantly longer than the mean GET of healthy subjects (87.8 ± 23.4 vs. 55 ± 18 min, p < 0.05). The mean GET of each therapy subgroups was significantly longer than the healthy subjects (the mean GET was 85.1 ± 22.4 min for hemodialysis, 87.7 ± 31.8 min for peritoneal dialysis, and 94.6 ± 16.7 min for renal transplant patients, respectively, p < 0.05). On the other hand, the differences in the mean GET between the three therapy subgroups were not statistically significant (p > 0.05). In addition, time on replacement therapy inversely and blood glucose positively correlated with GET in renal transplant patients. In conclusion, GET was longer in patients on all three RRT modalities than in healthy subjects. GET was not significantly different in dialysis patients and renal transplant patients.

Comparison of indium-111 octreotide and thallium-201 scintigraphy in patients mammographically suspected of having breast cancer: preliminary results

Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series.

Tc-99m HMPAO brain perfusion imaging in young Down's syndrome patients

Downs syndrome (DS) is characterized by moderate mental retardation and a variety of abnormalities involving multiple organ systems. There is a high incidence of Alzheimers disease (AD) type dementia beyond the age of 35. In this study, single photon emission computed tomography (SPECT) brain perfusion imaging of young Downs syndrome patients was performed to define the perfusion pattern. Tc-99m HMPAO brain perfusion SPECT was performed on 17 young DS patients, aged 3-24 years (mean: 10.9+/-5.9 years). None of the patients had dementia symptoms. Brain perfusion scans were acquired 15 min after i.v. injection of 12 MBq/kg of Tc-99m HMPAO using a single head rotating gamma camera. Images were analyzed visually and semiquantitatively by defining side-to-side asymmetry index. Nine DS cases showed normal brain perfusion. Eight of the 17 cases revealed mostly unilateral parieto-temporal, parieto-occipital and frontal hypoperfusions. The side-to-side asymmetry indices for these visually interpreted regional brain perfusion abnormalities ranged from 6 to 15%. These findings revealing mostly unilateral parieto-temporal and frontal hypoperfusions may not be considered as predictive patterns of dementia related Alzheimer type perfusion deficits in DS. However, such findings may connect to other functional imaging studies related to the higher cortical dysfunction in mental retardation.

99mTc ethylene dicysteine scintigraphy for diagnosing cortical defects in acute pyelonephritis: a comparative study with 99mTc dimercaptosuccinic acid.

AimTo evaluate the clinical usefulness of early cortical phase images in the diagnosis of acute pyelonephritis and to compare the measurements of differential renal function obtained by both 99mTc ethylene dicysteine (99mTc-EC) and 99mTc dimercaptosuccinic acid (99mTc-DMSA). MethodsForty-three children who had undergone both 99mTc-EC and 99mTc-DMSA studies within 5 days of acute infection were studied. Cortical images of 99mTc-EC were obtained by the sum of the renogram frames achieved between the first 60–120 s of the renogram study. DMSA and EC images were visually interpreted using four points of semiquantitative ratings: 0, normal; 1, mild hypoactivity; 2, moderate hypoactivity with partial loss of margins; 3, marked hypoactivity with loss of cortical margins. Values for the differential renal function were obtained for both studies. ResultsDMSA detected a total of 109 lesions in 36 patients and EC detected 90 lesions with a sensitivity of 82.5%. 99mTc-EC successfully detected moderate-to-severe cortical lesions but was less effective with mild lesions (sensitivity 60%). Bland–Altman analysis demonstrated good agreement among the results for differential renal function (95% CI −0.26 to 0.96). Conclusion99mTc-EC early phase images detected most of the cortical lesions. Its sensitivity depends on the severity of the lesions. EC provided reliable information in the estimation of differential renal function.

The use of technetium-99m hexamethylpropylene amine oxime lung scintigraphy in the detection of subclinical lung injury in patients with noninsulin-dependent diabetes mellitus.

Purpose:The aims of this study were to evaluate subclinical pulmonary injury in patients with noninsulin-dependent diabetes mellitus (NIDDM) who showed normal chest radiograph and pulmonary function test results by using technetium-99 hexamethylpropylene amine oxime (Tc-99m-HMPAO) scintigraphy and to investigate the relationship between Tc-99m-HMPAO lung uptake and duration of diabetes, glycemic control, and the presence of diabetes-related microvascular complications. Materials and methods:A total of 40 patients with NIDDM (19 men, 21 women; age 56.5±6.8 years; duration of diabetes: 13.1±6.7 years) were included in this study. The pulmonary vascular damage was represented as lung/liver uptake ratios (L/L ratios) calculated by Tc-99m-HMPAO lung scintigraphy. Results were compared with those of age-matched controls. Results:The L/L ratio was 0.36±0.07 in normal controls and 0.51±0.16 in patients with NIDDM. The L/L ratio was significantly higher in NIDDM patients than in the control group (P=0.002). No correlation was observed between L/L ratio and the presence of diabetic complications, glycemic control, and diabetes duration. Conclusion:Tc-99m-HMPAO lung scintigraphy is a sensitive and an objective method for the detection of subclinical lung injury in NIDDM patients. Tc-99m-HMPAO lung uptake serves as an indicator of pulmonary injury due to diabetes, regardless of diabetes age, glycemic control, and the presence of other diabetes-related microvascular complications.

Relationship between primary lesion metabolic parameters and clinical stage in lung cancer

OBJECTIVES The relation of PET-derived parameters as maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), metabolic tumor volume (MTV) with clinical stage in lung cancer and correlation of SUVmax of primary tumor and that of metastatic lesion was studied in lung cancer patients. MATERIALS AND METHODS Patients with lung cancer who were referred for FDG PET/CT were included in the study. RESULTS PET/CT scans and pathology reports of 168 patients were assessed. A total of 146 (86.9%) of these patients had a diagnosis of non-small cell lung cancer (NSCLC) and 22 (13.1%) had small cell lung cancer (SCLC). Metabolic parameters such as SUVmax, TLG and MTV showed significant differences in all the stages in NSCLC patients (p<0.001). However, after tumors sizes <25 mm were excluded, no significant differences in SUVmax between stages were observed. No significant differences were found between these metabolic parameters and limited or extended disease SCLC. Tumor diameter correlated with primary tumor SUVmax and significant correlations between primary lesion SUVmax and metastatic lesion SUVmax were found. CONCLUSIONS Although differences were found regarding indices between stages of NSCLC cases, SUVmax differences between stages seem to be caused by underestimation of SUVmax in small lesions. Other glucose metabolism indexes such as MTV and TLG show promising results in terms of prognostic stratification. Future studies are needed for better understanding of their contribution to clinical cases.