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Mehmet Reyhan

Publications and source records attributed to Mehmet Reyhan.

12 recordsLinked to original sources
PubMed2005

Gastroesophageal scintigraphy in children: a comparison of posterior and anterior imaging.

The purpose of this study was to compare the posterior dynamic imaging with the anterior imaging in the evaluation of children with gastroesophageal reflux (GER). Sixty-eight children (26 female, 42 male; age range 4 months to 7 years, median 21 months) were studied. After 4-hour fasting, all the subjects underwent gastroesophageal scintigraphy. Synchronous dynamic imaging in the anterior and posterior projections was performed with the subject in the supine position with a dual-head gamma camera equipped with low-energy general-purpose collimators at a rate of 30 s/frame for 40 min. The anterior and posterior images were visually evaluated for the presence of gastroesophageal reflux by two nuclear medicine physicians. The anterior and posterior images were correlated by Pearson correlation analysis, and inter-observer variability was evaluated by paired t-test and kappa value. There was a good correlation between the two projections with r-values of 0.906-0.990. The inter-observer agreement for interpretation of the anterior and posterior imaging was excellent (k: 0.83). In conclusion, anterior and posterior dynamic imaging showed excellent correlation in detection of GER in children. Posterior imaging is superior to anterior imaging in that it is more comfortable, and it reduces motion artifacts, especially for infants and anxious children; thus, it may be preferred over anterior imaging.

Child↗
PubMed2005

The conditions for which the geometric mean method revealed a more accurate calculation of relative renal function in 99mTc-DMSA scintigraphy.

AIMS: (1) To compare the results of calculating relative renal function (RRF) by using only posterior images (POST) with the geometric mean (GM) through both anterior and posterior imaging on dimercaptosuccinic acid (DMSA) scintigraphy. (2) To determine whether there was an age-related difference between them and whether some renal pathologies or asymmetrical renal function cause an error in the RRF calculation by using posterior images only. METHODS: Eight hundred and ninety-one DMSA scans were studied retrospectively. The patients were divided into five age groups: group I, < or =2 years; group II, >2 to < or =5 years; group III, >5 to < or =10 years; group IV, >10 to < or =18 years; and group V, >18 years. The RRF of the right kidney (RKF) was calculated from the POST and GM counts. The differences between RKFGM and RKFPOST were calculated in all the patients. RESULTS: Among the 891 patients, nine had malrotated or malpositioned kidneys, 373 had renal pathologies of pyelonephritis, hydronephrosis, cortical scarring and atrophy, 247 had asymmetrically functioning kidneys and 509 had normal kidneys. When the patients were analysed according to different age groups, significant differences were found between all groups (P<0.05) except groups I-II and IV-V (P>0.05) with the F-test. The clinically meaningful RRF variance (> or =5% difference between two methods) rate differed significantly between groups I, II and III, and groups IV and V (chi-squared test, P<0.05). In patients aged < or =10 years, a clinically meaningful RRF variance (> or =5%) rate was significantly higher in the groups with pathological or asymmetrically low (< or =40% RRF) functioning kidneys than in the groups without pathological or asymmetrically low functioning kidneys, respectively (P<0.05). CONCLUSIONS: According to our findings, the calculation of RRF using the GM method differs significantly from that using posterior images. Calculation of the GM can effectively correct the RRF measurement not in only adults, but also in the patient population musical #10 years of age. In addition, a significant correction can be made in patients aged musical #10 years who have a renal pathology or an asymmetrically low functioning kidney.

Adolescent↗
PubMed2005

Scintigraphic findings in osteoarticular brucellosis.

AIMS: To describe the distribution of bone and joint involvement in 197 patients with brucellosis, and to detail a spectrum of findings on bone scintigraphy in 38 patients with brucellar spondylitis. METHODS: One hundred and ninety-seven patients (141 females, 56 males; age range, 5-77 years) with osteoarticular brucellosis were studied. Patients were classified into acute (62%) and chronic (38%) stages of the disease, and into age groups of less than 16 (1%), 16-30 (17%), 31-45 (29%), 46-60 (37%) and over 60 (16%) years. All patients were evaluated with Tc-methylene diphosphonate bone scanning. Quantification of sacroiliac joint uptake was performed to improve the sensitivity for the detection of sacroiliitis. Plain radiography and computed tomography (CT) or magnetic resonance imaging (MRI) were performed, when required, to evaluate the areas of the skeleton that showed abnormal uptake on the bone scan. MRI and single photon emission computed tomography (SPECT) were performed in all patients who had spinal lesions. RESULTS: The sites most commonly affected were the sacroiliac joints (53%) and spine (19%), followed by the shoulders (16%). Osteoarticular involvement was more common in females (72%) than in males (28%), and the acute stage (62%) was observed more than the chronic stage (38%). Bone and joint involvement occurred at any age, but the most common age group was 46-60 years. Eight scintigraphic patterns were identified in spinal involvement. CONCLUSION: Brucellosis may affect the musculoskeletal system at any site. Bone scan is a useful method to detect osteoarticular involvement in cases of relapse and progression. Spine involvement has the widest range of scintigraphic findings. A knowledge of the location and distribution of osteoarticular involvement as revealed on the bone scan of patients with brucellosis may be valuable in patient treatment and management.

Adolescent↗
PubMed2004

Assessment of the optimal time interval and background region of interest in the measurement of differential renal function in Tc-99m-EC renography.

BACKGROUND: Differential renal function (DRF) measurements are routinely corrected for background, which mainly affects the reproducibility and accuracy of the measurement. The present study was conducted to identify the most appropriate background ROI and optimal time interval in the calculation of DRF for EC renography. MATERIALS AND METHODS: Nineteen patients were studied. For determination of DRF in EC renography, the selected time intervals were 0.5-1.5; 0.5-2; 1-2; 1.5-2.5; 2-3 min, and the background ROI types were inferolateral crescent, lateral crescent, and perirenal shaped. The reference DRF was obtained through DMSA study. For low functioning kidney of each patient, relative uptake differences between the DMSA and EC scans were calculated. Then, the mean differences and the standard deviations were found. RESULTS: The highest correlation was between the DRF values obtained using inferolateral background ROI in 0.5-2 minutes of EC scintigraphy and the DRF values obtained through posterior DMSA images (r = 0.9889). However, there were no statistically significant differences between the mean DRF values obtained for each time interval with each ROI type (p > 0.05). For all the time intervals and background ROIs, the mean of the differences was <0.9%. In conclusion, in obtaining comparable DRF values from EC and DMSA studies, none of the background types proved superior. Also our research for optimal time interval showed that EC scintigraphy underestimates the DRF when compared to DRF obtained from DMSA study. The DRF has a tendency to decrease as the later time intervals are used. The time intervals less than 2.5 minutes show lower underestimation of DRF values.

Adolescent↗
PubMed2004

Diffuse splenic Tc-99m MDP uptake in hypersplenic patient.

A 52-year-old woman with nonspecific left leg pain was examined by Tc-99m methylene diphosphonate (MDP) bone scintigraphy. The patient had been a marble quarry worker for 10 years and had developed chronic congestive heart failure secondary to pneumoconiosis. Her hemoglobin analysis and hematologic findings were interpreted as being consistent with sickle cell beta+ thalassemia and also hypersplenism. Bone scintigraphy showed intense and diffuse MDP accumulation in the enlarged spleen without ultrasonographic or radiologic evidence of calcification.

Anemia, Sickle Cell↗