Mustafa Kibar

Comparison of direct radionuclide cystography and voiding direct cystography in the detection of vesicoureteral reflux

Purpose: The aim of this study is to compare the results of direct radionuclide cystography (DRNC) and voiding cystourethrography (VCUG) in a group of children with a high suspicion of vesicoureteral reflux (VUR).Methods: For this purpose, 25 children were studied with both VCUG and DRNC. Among 50 ureter units able to be compared 39 ureter units did not show any VUR on either study. Eleven ureter units (10 children) had VUR either on one study or on both (VCUG and DRNC). In the children who had VUR on either study, a dimercaptosuccinic acid scintigraphy (DMSA) was performed to determine their cortical function.Results: We identified the following four patterns: 1) Five ureter units (five children) read positive on DRNC who were negative on VCUG and four of these children had positive findings on DMSA; 2) Four ureter units (four children) read positive on VCUG who were negative on DRNC, and two of them had positive findings on DMSA; 3) Two ureters (one child) read positive in both studies and also had abnormal DMSA findings; 4) Thirtynine ureter units read as negative on both studies.Conclusion: Although the results of these two methods did not show a significant difference, DRNC offers a high sensitivity in the younger age group whereas VCUG seems to be more sensitive in the older age group. DRNC also offers continuous recording during the study, ease of assessment and lower radiation dose to the gonads, which makes it a preferable method for the initial diagnosis and follow-up of VUR.

Technetium-99m-N,N-ethylenedicysteine and Tc-99m DMSA scintigraphy in the evaluation of renal parenchymal abnormalities in children

Technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) as a static renal agent is currently the most frequently used agent in the detection of renal scarring, and allows accurate calculation of differential renal function (DRF). But this agent has some disadvantages such as relatively higher radiation dose and time consumption.Methods: The purpose of this study was to evaluate the potential of summed image that obtained from parenchymal phase of the dynamic technetium-99m-N,N-ethylenedicysteine (Tc-99m EC) scintigraphy in the detection of renal parenchymal defects and in the estimation of DRF, and to compare the results of this method with those of Tc-99m DMSA scintigraphy. The uptake ratios of the kidney to body background were also calculated for these two methods. Twenty-nine children with various renal disorders underwent both static Tc-99m DMSA and dynamic Tc-99m EC scintigraphy. The cortical analysis of Tc-99m EC scintigraphy was performed on the summed image obtained from dynamic images using the time interval between the first 45–120 sec.Results: There was a very close correlation between these two methods with respect to DRF (r=0.99). In the detection of renal parenchymal lesions, scintigraphy with Tc-99m DMSA detected more lesions, and the sensitivity and specificity of the summed Tc-99m EC images were calculated as 92.6% and 100%, respectively. In addition, the ratios of mean uptake values for Tc-99m DMSA and Tc-99m EC images were 7.59±2.17 and 2.95±0.91, respectively. This ratio of Tc-99m EC seems to be acceptable and allows good delineation of the kidneys. But, the main disadvantages of the summed Tc-99m EC images in comparison with static Tc-99m DMSA images are the use of only posterior projection that may be an important drawback in patients with abnormal kidney positions, lower image counts and higher pixel size because of dynamic acquisition.Conclusion: These results show that summed Tc-99m EC images with an acceptable high image contrast provide an accurate DRF calculation in patients without abnormal kidney positions and allow the detection of most renal parenchymal abnormalities. However, Tc-99m DMSA scintigraphy remains the gold standard method because of its well known advantages.

Thyroid hemiagenesis: a report of three cases and review of the literature

Thyroid hemiagenesis resulting from the failure of embryologic development of one thyroidal lobe is a very rare anomaly. It is usually incidentally discovered during the investigation of accompanying thyroid disorders. Here we report three cases with right lobe agenesis in two patients and left lobe agenesis in one patient. Two of them were hyperthyroid, while the other euthyroid patient had a thyroid mass.

A technetium-99m hexamethylpropylene amine oxime brain single-photon emission tomography study in adolescent patients with major depressive disorder

Abstract. We have not encountered any brain single-photon emission tomography (SPET) study performed in adolescent depressed patients in the literature. Therefore, we used technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) brain SPET in adolescent patients with major depressive disorder (MDD) to examine the possible changes in cerebral perfusion and the possible association between perfusion indices and clinical variables. Fourteen adolescent out-patients (nine females, five males; mean±SD age: 13.11±1.43 years; range: 11–15 years) fulfilling the DSM-IV criteria for MDD and 11 age-matched healthy control subjects (six females, five males; mean±SD age: 13.80±1.60 years; range: 12–15 years) were included in the study. 99Tc-HMPAO brain SPET was performed twice in the patient group and once in the control group. The first SPET investigation was performed under non-medicated conditions and the second was performed after depressive symptoms had subsided. A relative perfusion index (PI) was calculated as the ratio of regional cortical activity to the whole brain activity. We found significant differences between the PI values of the untreated depressed patients and those of the controls, indicating relatively reduced perfusion in the left anterofrontal and left temporal cortical areas. No significant differences in regional PI values were found between the remitted depressed patients and the controls. Our study suggests that adolescent patients with MDD may have regional cerebral blood flow deficits in frontal regions and a greater anterofrontal right-left perfusion asymmetry compared with normal subjects. The fact that these abnormalities in perfusion indices have a trend toward normal values with symptomatic improvement suggests that they may be state-dependent markers for adolescent MDD.

Staging with PET-CT in Patients with Locally Advanced Non Small Cell Lung Cancer is Superior to Conventional Staging Methods in Terms of Survival

BACKGROUND Of patients with non small cell lung cancer (NSCLC), around one third are locally advanced at the time of diagnosis. Because only a proprotion of stage III patients can be cured by surgery, in order to improve the outcomes, sequential or concurrent chemoradiation, or concurrent chemoradiation with induction or consolidation is offered to the patients with locally advanced NSCLC. Today, PET combined with computerized tomography (PET-CT) is accepted as the most sensitive technique for detecting mediastinal lymph node and extracranial metastases from NSCLC. We aimed to compare PET-CT and conventional staging procedures for decisions regarding curative treatment of locally advanced NSCLC. MATERIALS AND METHODS A total of 168 consecutive patients were included from Acibadem Kayseri Hospital, Acibadem Adana Hospital and Kayseri Research and Training Hospital in this study. RESULTS While the median PFS was 13.0 ± 1.9 months in the PET-CT group, it was only 6.0 ± 0.9 in the others (p<0.001). The median OS values were 20.5 ± 15.6 and 11.5 ± 1.5 months, respectively (p<0.001). DISCUSSION As a result, we found that staging with PET CT has better results in terms of survival staging. This superiority leads to survival advantage in patients with locally advanced NSCLC.

The role of endothelin in radiocontrast nephropathy

In the present study we investigated the role of endothelin and AT II in radiocontrast nephropathy induced in rats with reduced renal mass (70–75%). Thirty-five male Wistar albino rats weighing between 280 and 400 g were anaesthetized with ketamine (130 mg/kg b.w.) and right total, left 50% nephrectomy were performed. After this operation, the rats were kept under observation for six to eight weeks and then they were randomly separated into three groups. Group I rats were infused with 8.9 ml/kg (or 2.9 g of iodine/kg body weight) Na diatrizoate (Urovision, 1500 mosm/kg). Group II rats were infused with 0.9% NaCl in an equal volume with the radiocontrast material. Group III rats were given 4.5% NaCl that had the same volume and osmolality as the radiocontrast material. Two hours after the drug infusions, blood and accumulated urine samples were collected from all the rats and tested for endothelin, AT II, BUN, creatinine, uric acid, electrolytes, calcium and phosphorus. We found that the plasma endothelin levels in Group I (77.64±29.62 pg/ml) were significantly higher than in Group II (20.52±5.83 pg/ml) and Group III (15.04±5.15 pg/ml) (t=8.34 and t=9.14, respectively, p<0.001). Therefore elevation in circulating endothelin might have been an additional factor leading to the radiocontrast-induced nephrotoxicity.

Gastric emptying time and the effect of cisapride in cirrhotic patients with autonomic neuropathy.

Goals To investigate the relationships between gastric emptying and autonomic dysfunction in hepatic cirrhosis and to assess the effects of cisapride on gastric emptying in cirrhotic patients. Study Twenty-four cirrhotic patients (8 patients in each Child–Pugh classification) and 25 healthy controls were enrolled. All the patients had viral (B or C) hepatitis. Patients with DM, alcoholic cirrhosis, active peptic ulcer, gastric malignancy and pyloric obstruction were excluded by esophagogastroduodenoscopy. Parasympathetic and sympathetic functions were assessed by the criteria set forth by Ewing and Clark. Drugs affecting GI motility and smoking were discontinued 48 hours and 12 hours prior to the study respectively. A solid-phase of gastric emptying study was conducted by scintigraphic method for the calculation of gastric half-emptying time (GET1/2). Results The study revealed that 9 patients with Child–Pugh B and C cirrhosis had autonomic neuropathy and none of Child–Pugh A cirrhosis had autonomic neuropathy. Prolonged GET1/2 was noted in cirrhotics compared with the control group (p < 0.05). However, there was significant difference between 9 patients (Child B-C) with autonomic neuropathy compared with patients 15 patients without autonomic neuropathy. Again there was a significant difference in GET1/2 between Child A cirrhotic and Child B-C cirrhotic whether they had autonomic neuropathy or not. Cisapride decreased GET1/2 significantly in cirrhotic patients (Child B-C cirrhotic). Clearly, patients with autonomic neuropathy in Child B-C cirrhosis had significantly reduced GET1/2 after cisapride administration. Even though cisapride decreased GET1/2 in patients with Child B-C cirrhosis without autonomic neuropathy, this was not significant. Conclusion Autonomic neuropathy in advanced cirrhosis from viral hepatitis may cause prolonged gastric emptying. Cisapride can shorten gastric emptying time in such patients.

99Tcm-N,N-ethylenedicysteine scintigraphy in children with various renal disorders: a comparative study with 99Tcm-MAG3.

We evaluated the clinical usefulness of 99Tcm-N,N-ethylenedicysteine (99Tcm-EC), a new renal tubular agent, in normal children and in children with various renal disorders and compared it with 99Tcm-mercaptoacetyltriglycine (99Tcm-MAG3). In a first group of children (Group 1), which included 15 patients and 4 normal children, both 99Tcm-EC and 99Tcm-MAG3 renal scintigraphy were performed within a period of 1-5 days. In a second group (Group 2), consisting of 12 patients, only 99Tcm-EC scintigraphy was performed. In the normal children, renograms, differential renal function (DRF) ratios and semi-quantitative parameters of the two agents were similar. For 99Tcm-EC and 99Tcm-MAG3, the mean (+/- S.D.) time to peak activity (Tmax) values were 3.2 +/- 0.5 and 3.1 +/- 0.4 min respectively, and the mean time from peak activity to 50% activity (T1/2) values were 6.3 +/- 0.5 and 6.4 +/- 0.4 min respectively. The mean parenchymal transit time index (PTTI) and mean whole-kidney transit time index (WKTTI) for 99Tcm-EC were 1.7 +/- 0.3 and 2.8 +/- 0.4 respectively, and for 99Tcm-MAG3 they were 1.8 +/- 0.2 and 3.0 +/- 0.3 min respectively. There were also no significant differences between these parameters for the two agents in children with various renal disorders, and the correlation coefficients (r) for DRF, Tmax, T1/2, PTTI and WKTTI were 0.99, 0.98, 0.94, 0.77 and 0.63 respectively. We conclude that 99Tcm-EC has excellent imaging characteristics in children, and even has some advantages over 99Tcm-MAG3. We suggest this agent can be used routinely with children.

Washout rates of Tc-99m tetrofosmin in asymmetric septal hypertrophy

The aim of this study was to evaluate the washout rate of Tc-99m tetrofosmin in asymmetric septal hypertrophy (ASH). As Tc-99m tetrofosmin accumulation and retention depend on sarcolemmal and/or mitochondrial function, the presence or absence of abnormalities in the washout rate of Tc-99m tetrofosmin could provide information about sarcolemmal and/or mitochondrial damage noninvasively. The study group consisted of 18 patients with ASH and 10 healthy subjects. After intravenous injection of 1,110 MBq (30 mCi) Tc-99m tetrofosmin, tomographic images were obtained 1 hour later (early image) and again 4 hours later (delayed image). Using tomographic images, the distribution and washout of tetrofosmin in the left ventricle was examined quantitatively. Short-axis SPECT images were divided into 5 segments (anterior, septal, lateral, inferior wall and apex) in early and delayed images, and the mean radioactivity counts were measured in each segment by drawing regions of interest. Washout rates of apex, anterior, septal, lateral and inferior walls were 0.34 ± 0.06, 0.37 ± 0.07, 0.36 ± 0.07, 0.33 ± 0.08, 0.33 ± 0.07 in ASH and 0.20 ± 0.05, 0.23 ± 0.05, 0.22 ± 0.03, 0.21 ± 0.03, 0.22 ± 0.03 in the normal group, respectively. In ASH, the washout rates of all myocardial segments were significantly increased as compared to those of the normal controls (p < 0.05). The findings of the present study suggest that there could be dysfunction of sarcolemma and/or mitochondria in the entire left ventricle which would be important in the pathophysiology of this disease. Also our study revealed that Tc-99m tetrofosmin washout was higher in NYHA II—III patients compared to NYHA I patients and the degree of Tc-99m tetrofosmin washout corresponded well with the thickness of the interventricular septum and posterior walls.

99mTc-tetrofosmin scintigraphy in musculoskeletal tumours: the relationship between P-glycoprotein expression and tetrofosmin uptake in malignant lesions

The aims of this study were to assess the role of 99mTc-tetrofosmin scintigraphy in the diagnosis of maligniant vs. benign musculoskeletal tumours and to determine the relationship between P-glycoprotein expression and tetrofosmin uptake in malignant lesions. Forty-six patients (32 malignant, 14 benign) with various musculoskeletal lesions were studied. Each patient underwent 99mTc-methylene diphosphonate three-phase bone scanning initially. At least 2 days later, dynamic and static 99mTc-tetrofosmin scans were obtained. The tetrofosmin scans were evaluated by visual and quantitative analysis. The count ratio of the lesion to the contralateral normal area (uptake ratio, UR) was calculated from the region of interest drawn on the tetrofosmin scan. The lesions were then resected by open biopsy to obtain a histopathological diagnosis. P-glycoprotein levels were determined immunohistochemically in 22 of 32 malignant lesions. A significant difference between the mean UR values of benign and malignant lesions was found (1.36±0.47 vs. 3.35±2.08, P = 0.000). Visual analysis showed an accuracy of 85%, and the accuracy of the quantitative analysis was 87% with the threshold level of UR as 1.76. When perfusion findings were added to the evaluation criteria, the accuracies of visual and quantitative analysis were increased to 87% and 89%, respectively. The relationship between the levels of P-glycoprotein and the UR values of tetrofosmin was not statistically significant (r = −0.235, P = 0.2). In addition, the mean UR value of the patients with P-glycoprotein expression was not statistically different from that of the patients without P-glycoprotein expression (3.01±1.48 vs. 4.27±2.90, P = 0.297). In conclusion, visually significant tetrofosmin uptake and increased perfusion in a musculoskeletal lesion strongly suggest that the lesion is malignant (positive predictive value, 96%). P-glycoprotein expression was not found to be a major factor interfering with 30 min tetrofosmin uptake in a malignant musculoskeletal lesion. However, the relatively high false-negative rate among negative results (28%) limits the value of 99mTc-tetrofosmin scintigraphy as a single diagnostic tool in differentiating between benign and malignant musculoskeletal tumours.