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C Bekdik

Publications and source records attributed to C Bekdik.

31 records · Page 2Linked to original sources
PubMed1992

Dual radioisotopic study: a technique for the evaluation of vasculogenic impotence.

Arterial and venous systems are the main points for the evaluation of vasculogenic impotence. To evaluate both of these systems in the same study we propose a dual radioisotopic study in which 99mtechnetium (99mTc) and 133xenon (133Xe) were used. The changes in 99mTc and 133Xe radioactivities administered intravenously and intracavernously, respectively, were monitored before and after intracavernous papaverine injection. These changes were determined as time activity curves, which were generated from the region of interest over the penis. A 99mTc penogram index derived from the 99mTc time activity curve was significantly different in the control and arteriogenic impotence groups (131.67 +/- 74.6 versus 62.94 +/- 51.6, p less than 0.01). A meaningful correlation between 99mTc penogram index results and duplex ultrasonographic findings were observed (r = 0.905). 133Xe penogram index, derived from the 133Xe washout curve was significantly different in the control and venogenic impotence groups (-25.65 +/- 24.9 versus -56.09 +/- 13.4, p less than 0.01). Also, a meaningful correlation was obtained between pharmacocavernosometry and 133Xe penogram index results of venogenic impotent patients (r = 0.86). These findings suggest that the dual radioisotopic study will be a useful technique in the evaluation of the entire vascular system of the penis, since it is a noninvasive method.

Adult↗
PubMed1992

Regional cerebral blood flow changes in chronic alcoholism using Tc-99m HMPAO SPECT. Comparison with CT parameters.

Twenty-eight patients were studied for regional cerebral blood flow changes as a result of chronic alcoholism. After the administration of 550 to 600 MBq Tc-99m HMPAO, tomographic slices were obtained using a SPECT camera. Eight regions per hemisphere were drawn on each transaxial section, and tracer redistribution was calculated for each region. Region-to-whole slice ratios were determined for each patient. Patients had significantly decreased frontal/whole slice (1 +/- 0.02) ratios in comparison with a normal group (p less than 0.01). Twenty-four out of 26 patients (85.7%) demonstrated abnormal rCBF. Eighteen out of 28 (64.3%) showed activity lower in the left hemisphere than in the right. Using CT parameters, 60% of the patients had either sulcal widening and/or ventricular enlargement. The frontal region and the left hemisphere were more affected by alcohol than other regions. More cerebral blood flow changes than morphologic changes were found caused by alcoholism.

Adult↗
PubMed1992

Technetium-99m-MIBI uptake in benign and malignant bone lesions: a comparative study with technetium-99m-MDP.

The potential of hexakis (methoxyisobutylisonitrile) technetium (1) (MIBI) for the imaging of various bone pathologies and for assessment of effectiveness of therapy were investigated in a prospective study. MIBI was evaluated in comparison to MDP bone scans in 73 bone lesions (31 benign, 42 malignant). With MIBI, all but six malignant lesions were clearly visualized and the mean lesion/contralateral (L/C) ratio (2.21 +/- 1.17) was significantly higher than that of benign counterparts (1.26 +/- 0.40) (p less than 0.0005). No such significance was detected on corresponding MDP bone scans (4.86 +/- 3.48 versus 3.11 +/- 1.52). Ten cases with malignant tumor underwent both pre- and post-therapy MIBI evaluation and it was demonstrated that radiotherapy and/or chemotherapy significantly inhibited MIBI uptake. Moreover, post-therapeutic MIBI uptake was a good reflection of the effectiveness of therapy as confirmed by histopathological evaluation. Thus, with a strikingly higher uptake in malignant bone lesions MIBI might have good potential for the detection of malignant bone pathologies as well as for assessing tumor response to therapy.

Adolescent↗
PubMed1991

Detection of deep vein thrombosis: combined flow and blood pool radionuclide venography vs contrast venography.

This study was performed to validate the combined study of flow radionuclide venography (FRV) with subsequent 99mTc-red blood cell(RBC) blood pool radionuclide venography(BRV) for the detection of deep vein thrombosis (DVT). Findings in 32 patients with suspected DVT of lower extremities (n = 52) were compared with those of corresponding contrast venograms (CV) serving as a reference method. FRV was performed by using three separate doses of a large 99mTc04-bolus (10-12 cc) injection. The findings were as follows: concerning the detection of DVT in calf veins, agreement between FRV and CV, FRV+BRV and CV, and BRV and CV were 67%, 73% and 60%, respectively. For femoral veins, agreement between FRV and CV was 96%, while it was 87% between BRV and CV. When FRV and BRV of femoral veins were evaluated in combination, 100% agreement between radionuclide and radiologic method was observed. For iliac veins there was no disagreement in comparison of the methods either singly or in combination. In 7.6% of the extremities, collaterals not demonstrated by CV and BRV were visualized only by FRV. Although the radioactive agent was injected in a relatively large volume, all of the calf veins could not be filled even when they were completely patent. It was concluded that a combined study of FRV with BRV improved the diagnostic value of radionuclide venography for the detection of DVT in calf and femoral veins.

Adult↗
PubMed1991

Radionuclide hysterosalpingography. A simple and potentially useful method of evaluating tubal patency.

A prospective study was undertaken to evaluate the efficacy of radionuclide hysterosalpingography (RN-HSG) using 99mTc-labeled human albumin microspheres to assess the patency of the fallopian tubes in 36 women (72 tubes). The study group consisted of 20 women with proven fertility undergoing laparoscopic tubal ligation, 8 with male factor infertility and 8 with bilateral isthmic tubal occlusion. All RN-HSG scan results were correlated with the findings at laparoscopy when tubal patency was ultimately assessed with chromopertubation. The sensitivity and specificity of RN-HSG were 100% and 94.6%, respectively. The positive predictive value (probability of occlusion when RN-HSG was positive) was 84%, whereas the negative predictive value (probability of no occlusion when RN-HSG was negative) was 100%. RN-HSG is a simple and potentially useful method of assessing the patency of the fallopian tubes.

Albumins↗
PubMed1990

Functional asplenia and portal hypertension in a patient with primary splenic hemangiosarcoma.

A 60-year-old man with primary splenic hemangiosarcoma (PSH) presented with weakness, weight loss, abdominal pain, and anemia. Physical examination revealed hepatomegaly, ascites, and firm, huge splenomegaly. Ultrasonography showed many nodular structures characterized by hypoechogenic and hyperechogenic areas. The patient also had portal hypertension, which was confirmed by physical findings and by measurement of portal vein pressure during operation. A liver-spleen scan using Tc-99m sulfur colloid and Tc-99m labeled heat denatured erythrocytes failed to demonstrate any splenic uptake, a reliable feature of functional asplenia. Although on a total body scan with Ga-67 citrate there was no splenic uptake, there was gallium uptake in the liver, where the presence of the metastatic lesion was histopathologically verified and confirmed by operation. There was also uptake in the middle zones of the lungs. Ga-67 citrate imaging appears to be helpful in the diagnosis of metastasis of PSH, and PSH can rarely cause portal hypertension.

Gallium Radioisotopes↗
PubMed1990

Tc-99m HMPAO/SPECT determination of regional cerebral blood flow changes in schizophrenics.

Hypofrontality (hypometabolism and hypoperfusion) has been demonstrated in patients with schizophrenia by the use of several imaging methods, such as positron emission tomography (PET). In this study, Tc-99m hexamethylpropylene amineoxime (HMPAO) and SPECT were used to investigate regional blood flow changes in 20 schizophrenic patients (12 males and 8 females, aged 15-50 years) experiencing acoustic hallucinations. Tc-99m HM-PAO (15-20 mCi) was injected intravenously, eight regions/hemisphere were drawn on transaxial sections, and tracer redistribution was calculated for each region. Frontal/occipital ratios (0.917 +/- 0.045) and frontal/whole-slice ratios (0.984 +/- 0.036) were determined for each patient. The patients had significantly lower frontal/occipital ratios (P less than 0.0005) and lower frontal/whole-slice ratios (P less than 0.01) in comparison to a normal group (11 cases).

Adolescent↗
PubMedDate not supplied

Lymphoscintigraphic evaluation of primary congenital lymphedema.

A-four-year-old girl with primary nonfamilial congenital lymphedema was evaluated by lymphoscintigraphy using 99mTc-Dextran. It was demonstrated that there was no accumulation of radioactivity in the left inguinal and femoral lymph nodes and faint accumulation in the contralateral lymph node. It was concluded that lymphoscintigraphy is a safe, reliable, noninvasive technique which is helpful in the evaluation of a patient with lymphedema, especially small children in whom conventional contrast lymphangiography offers some challenges.

Child, Preschool↗
PubMedDate not supplied

Detection of intracardiac left-to-right shunts in children by contrast echocardiography and the radionuclide technique.

This study was carried out in the Departments of Pediatrics and Nuclear Medicine at Hacettepe University Faculty of Medicine between April 1986 and March 1988 with the aim of detecting left-to-right shunts in 70 patients with isolated ventricular septal (VSD) defect, isolated atrial septal defect (ASD) and patent ductus arteriosus, by using the radionuclide technique together with contrast echocardiography. In some patients, the results were confirmed by both cardiac catheterization and angiocardiography. Most of the data were confirmed during surgery. A good correlation was found between the results of contrast echocardiography and radionuclide angiography. The difference between the QP/QS value and the grade of positive contrast effect was tested statistically and "p" was found to be less than 0.001. Therefore, we conclude that these methods could be applied together to determine the indication for surgery in cases with ASD or VSD.

Adolescent↗