Search PubMed⌕ Search

Biomedical subjects

B Caner

Publications and source records attributed to B Caner.

At least 19 recordsLinked to original sources
PubMed2001

Combined use of bone and bone marrow scintigraphies for the diagnosis of active sacroiliitis: a new approach.

Diagnosis of sacroiliitis (SI) with bone scintigraphy may involve difficulties even with a quantitative approach. The aim of this study was to evaluate the combined use of bone and bone marrow scintigraphies for the diagnosis of active sacroiliitis. Thirty-one patients who were clinically suspected to have SI were included in the study. Bone and bone marrow scintigraphies were done after injections of 740 MBq of 99mTc-MDP (MDP) and 370 MBq of 99mTc-sulfur colloid (SC) respectively with a 2-day interval. Both visual and quantitative assessment of MDP uptake and visual assessment of SC uptake in sacroiliac joints were performed. Also sacroiliac joint radiographic findings for each patient were evaluated and graded from 0 to 4 according to the New York grading system. Patients were divided into 2 groups according to their x-ray findings (Group A: grade 0-2, Group B: grade 3-4). A total of 14 patients (10 bilateral, 4 unilateral) had increased MDP uptake with decreased/normal SC uptake. Twelve of 14 patients had grade 0-2 radiographic changes while only 2 patients had grade 3-4 radiographic changes. Increased MDP uptake with decreased/normal SC uptake is the most common scintigraphic pattern seen in acute phase SI in which radiographic findings are generally found to be normal or slightly changed. In at least in 8 patients the decreased bone marrow uptake of SC was demonstrated, supporting the diagnosis. Although our results did not reveal any significant superiority of bone marrow scintigraphy to bone scan for the detection of active sacroiliitis, combined use of bone and bone marrow scintigraphies was presented as an alternative method to characterize patients with active sacroiliitis.

Adult↗
PubMed2001

Superiority of tc-99m MAG3 to tc-99m DTPA in treating a patient with mild renal artery stenosis.

A 22-year-old female patient with severe hypertension underwent both Technetium-99m diethylenetriaminepentaacetate and Technetium-99m mercaptoacetyltriglycine basal and captopril renal scintigraphy. While no significant change was seen with Tc-99m DTPA, there was left sided parenchymal retention of captopril Tc-99m MAG3 suggesting renal artery stenosis which was confirmed by angiography.

Adult↗
PubMed2001

Scintigraphic evaluation of synovial inflammation in rheumatoid arthritis with (99m)technetium-labelled human polyclonal immunoglobulin G.

The aim of this study was to investigate whether (99m)technetium-labelled polyclonal human immunoglobulin G (99mTc-IgG) scintigraphy reflects synovial inflammation in patients with rheumatoid arthritis (RA). We evaluated 29 patients with RA for this reason and found a highly significant correlation between total scintigraphic scores and total tenderness scores (r = 0.781, P < 0.001). A significant correlation was also found between 99mTc-IgG scintigraphic scores and tenderness in all joints other than the shoulders. The 99mTc-IgG scintigraphy had a sensitivity of 69% and specificity of 88% in cases with tenderness and 72% and 81%, respectively, in cases with swelling. Total scintigraphic scores were correlated with serum levels of C-reactive protein (r = 0.401, P < 0.05) but not with erythrocyte sedimentation rate (r = 0.149, P > 0.05). The correlation between disease activity scores and total scintigraphic scores was also found to be significant (r = 0.812, P < 0.001). We suggest that 99mTc-IgG scintigraphy is a reliable and objective method in detecting synovial activity and can be appropriate for observing disease prognosis in clinical trials with RA.

Adult↗
PubMed2001

Exercise-induced left bundle branch block during thallium 201 myocardial perfusion scintigraphy--a case report.

Exercise-induced left bundle branch block (Ex-LBBB) is a rare entity encountered during exercise testing. The authors present a 53-year-old woman who developed intermittent Ex-LBBB asymptomatically during Tl 201 myocardial perfusion scintigraphy. Scintigraphic findings revealed septal-anteroseptal ischemia while the coronary arteriogram appeared normal. False-positive septal-anteroseptal scintigraphic findings suggesting ischemia in patients with persistent left bundle branch block (LBBB) is well known, but since the LBBB in this case was induced by exercise testing and was spontaneously terminated at rest, scintigraphic findings may be attributed to microcirculatory ischemia, which cannot be detected angiographically, as the cause of Ex-LBBB.

Bundle-Branch Block↗
PubMed2000

Scintigraphic evaluation of impaction grafting for total hip arthroplasty revision.

To determine the fate of an impacted allograft after a minimum follow-up of 1 year, we examined 9 of 40 patients who underwent revision arthroplasty with the impaction grafting technique. The allograft used in this study was morselized cancellous freeze-dried allograft. We examined these 9 patients with technetium-99 m methylene diphosphonate bone scintigraphy at an average of 14 (range 12-20) months after surgery. All of them had a good clinical outcome, with an average postoperative Hip Society Score of 89 (range 65-98) and no evidence of radiolucency or subsidence on direct radiography. Scintigraphic examination demonstrated that the area corresponding to the allograft had a remarkable radioactivity accumulation suggesting new bone formation. The allograft in total hip revision using the impaction grafting technique undergoes a significant neovascularization and new bone formation. This study suggests than when vigorous impaction is used, freeze-dried cancellous allograft can be used for impaction grafting.

Arthroplasty, Replacement, Hip↗
PubMed2000

Tc-99m pertechnetate scintigraphy before and after potassium perchlorate administration for the diagnosis of retrosternal goiter.

A 52-year-old woman was hospitalized because of dyspnea and dysphagia. Thoracic computed tomography revealed a retrotracheal mass. Tc-99m pertechnetate scintigraphy showed intense accumulation of radioactivity corresponding to the mediastinal mass detected by computed tomography. Repeated Tc-99m pertechnetate scintigraphy performed after oral administration of potassium perchlorate (KCLO4) revealed complete disappearance of the radioactive accumulation in the mediastinum, suggesting that the retrotracheal mass was a retrosternal goiter. Subsequent surgical removal and analysis of the mass showed it was indeed a retrosternal goiter. This case highlights the importance of Tc-99m pertechnetate thyroid scintigraphy with and without KCLO4 administration as a simple, accurate, and cost-effective imaging method to diagnose retrosternal goiter.

Administration, Oral↗
PubMed2000

Immediate thallium re-injection after stress imaging for the detection of myocardial viability.

Myocardial perfusion imaging with thallium is an established method to assess the presence of ischaemic and viable myocardium. Using planar imaging, images acquired 1 h after immediate thallium re-injection have been shown to be comparable to those of 3 h redistribution. The aim of this study was to clarify this using SPET. Twenty patients with chronic coronary artery disease with at least two perfusion defects on post-exercise images participated in this study. All patients received thallium re-injection after post-stress SPET and all had 1 h, 3 h and 24 h redistribution imaging. The thallium myocardial tomograms were divided into 14 segments for each patient. A total of 78 segments were studied. When the frequency of reversibility on 1 h, 3 h and 24 h redistribution images is compared, of the 78 SPET defects 18 (23.1%) showed reversibility by 1 h, 34 (43.6%) by combined 1 h and 3 h imaging (P < 0.05) and 50 (64.1%) by combined 1 h, 3 h and 24 h imaging (P < 0.05). Our results show that, compared to 3 h images, images acquired 1 h after immediate thallium re-injection underestimate the extent of viable myocardial segments and the incidence of late reversibility was not reduced by the immediate re-injection of thallium.

Adult↗
PubMed2000

Dobutamine combined with low-level exercise for myocardial perfusion scintigraphy.

Increased abdominal background activity is one of the limitations of dobutamine myocardial perfusion scintigraphy which may interfere with interpretation of the images. In this study, we evaluated the value of low-level exercise supplementation to dobutamine infusion in improving image quality. The control group (n = 32, Group A) received dobutamine alone, while the study group received dobutamine plus low-level exercise for the last 2 min of dobutamine administration (n = 26, Group B). One hundred and eleven MBq of 201Tl was injected 1 min before cessation of peak dose. The ratios of cardiac/hepatic (C/HEP), cardiac/subdiaphragmatic (C/INF) and cardiac/pulmonary (C/PUL) were calculated from anterior planar images taken immediately following the test. Cardiac/non-cardiac activity was also visually graded on a three-point scale. Visual evaluation showed improved cardiac/non-cardiac ratios as confirmed by significantly higher C/HEP and C/INF ratios for Group B (1.5+/-0.3 and 1.7+/-0.2, respectively) compared to corresponding values in Group A (1.2+/-0.4 and 1.4+/-0.4, respectively) (P<0.05). The cardiac/pulmonary (C/PUL) ratio was also higher for Group B (2.3+/-0.5) as compared to corresponding value in Group A (2.0+/-0.6, respectively), but this difference did not reach statistical significance (P > 0.05). No difference in the frequency of side effects and ECG changes were detected between the two groups (P > 0.05). Low-level exercise supplementation to dobutamine infusion for myocardial perfusion scintigraphy is a safe method and leads to a significant decrease in uptake by the areas adjacent to the heart, improving image quality.

Aged↗
PubMed2000

Comparison of 99mTc-methoxyisobutyl isonitrile and 201T1 scintigraphy in visualization of suppressed thyroid tissue.

UNLABELLED: Both (201)TI and (99m)Tc-methoxyisobutyl isonitrile (MIBI) have been used in the visualization of suppressed thyroid tissue in patients with autonomously functioning thyroid nodules (AFTNs). It has been suggested that thyroid-stimulating hormone (TSH) control is not a major determinant of both tracers. However, the mechanism of thyroid uptake of these agents is controversial. In this study, we compared (201)TI and MIBI in the visualization of suppressed thyroid tissue in patients with a solitary toxic AFTN. METHODS: Thirty-two patients (13 triiodothyronine [T3] and 19 T3 + levorotatory thyroxine [T4] hyperthyroid patients) with toxic AFTNs visualized on (99m)Tc-pertechnetate scanning were included in the study. All patients underwent MIBI and (201)TI thyroid scintigraphy within a 3-d interval. The scintigrams were analyzed both visually and semiquantitatively. For the semiquantitative analysis, regions of interest (ROIs) were generated over the nodule (N) and contralateral normal lobe (E), and the mean counts in each ROI were calculated. RESULTS: The N/E uptakes (mean +/- SD) for pertechnetate, MIBI, and (201)TI were 11.37 +/- 4.53, 4.76 +/- 1.38, and 1.63 +/- 0.15, respectively, in T3 + T4 hyperthyroid patients and 9.46 +/- 3.64, 2.73 +/- 0.63, and 1.57 +/- 0.23, respectively, in T3 hyperthyroid patients. Our results showed that (201)TI uptake of suppressed thyroid tissue compared with AFTN was more prominent and significantly higher than that of MIBI for both groups of patients (P = 1.08E-05 for T3 and 6.15E-09 for T3 + T4 hyperthyroidism). There was no significant difference for either pertechnetate or (201)TI (P > 0.05) when the N/E uptakes of both groups of patients were compared. However, the N/E uptake of MIBI in T3 + T4 hyperthyroid patients was significantly higher than that in T3 hyperthyroid patients (P = 6.69E-06). CONCLUSION: Clear visualization of suppressed thyroid tissue with both (201)TI and MIBI in patients with low serum concentrations of TSH suggests that TSH is not a major factor in the thyroid uptake of either agent. (201)TI is superior to MIBI in the visualization of suppressed thyroid tissue in patients with a toxic thyroid nodule. An increased rate of metabolism in the follicular cells of AFTNs in T3 + T4 hyperthyroid patients compared with that in T3 hyperthyroid patients might be responsible for the higher N/E for MIBI compared with that for (201)TI.

Adult↗
PubMed1999

The effect of trimebutine maleate on gastric emptying in patients with non-ulcer dyspepsia.

The study was designed to investigate the effect of trimebutine maleate, a drug used in both hyperkinetic and hypokinetic motility disorders, on gastric emptying in patients with non-ulcer dyspepsia having prolonged gastric emptying rates and to compare the parameters used for the determination of the lag period observed during the emptying of solid foods from the stomach. Gastric emptying was measured by the radionuclide technique. Twenty normal volunteers and 43 patients with non-ulcer dyspepsia participated in the study. Radionuclide imaging was performed by using a solid meal labeled with 99mTc-tin colloid. Of the patients with non-ulcer dyspepsia, 20 had prolonged gastric emptying. They were given three weeks of oral treatment with trimebutine maleate and had their radionuclide gastric emptying study repeated. Treatment with trimebutine maleate resulted in reduction in duration of the lag period and less retention of food at 100 minutes (p < 0.0005). After treatment with trimebutine maleate, no significant difference has been observed in the mean symptom score of patients with prolonged gastric emptying. Among the parameters used for the determination of the lag period, lag period determined by a mathematical equation (TLAG) has been found to be longer than the lag period determined by visual inspection of the images (VLAG) and there was correlation between the two parameters when the lag time was short.

Administration, Oral↗
PubMed1999

Effect of silicone breast implants on myocardial imaging.

The authors investigated the effect of silicone breast implants (SBIs) on thallium-201 myocardial perfusion scintigraphy. Twenty-nine patients with SBIs and 14 control subjects were included in the study. All of the participants underwent a resting thallium-201 myocardial perfusion study. Comparison of the thallium images between patients with SBI and control subjects was done both visually and semiquantitatively. On visual analysis, neither image distortion nor image artifact attributable to the SBIs was noted. Semiquantitative analysis revealed that in patients with SBIs, the uptake values of the anteroseptal, anterolateral, lateroanterior, and lateroinferior myocardial walls was slightly, but significantly, lower than those of control subjects: anteroseptal, 87.7+/-6.0% vs. 92.8+/-5.1%; anterolateral, 88.0+/-5% vs. 92.6+/-4.5%; lateroanterior, 87.4+/-5% vs. 91.4+/-4.7%; and lateroinferior, 86.0+/-6.0% vs. 91.7+/-7.0%. The uptake value of the remaining walls in patients with SBIs were not significantly different than the control subjects. In conclusion, SBIs did cause a significant decrease in uptake values of the myocardial walls, which should be considered during interpretation of the images.

Adult↗
PubMed1999

Comparison of Tc-99m EC and Tc-99m DTPA captopril scintigraphy to diagnose renal artery stenosis.

PURPOSE: 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. METHODS: 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%. RESULTS: 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%; P > 0.05 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. CONCLUSIONS: 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.

Adult↗
PubMed1999

The relation between the degree of gastro-oesophageal reflux and the rate of gastric emptying.

In this study, we evaluated the relationship between the degree of gastro-oesophageal reflux and the rate of gastric emptying and determined the variability of gastric emptying in children. The reproducibility of radionuclide imaging for the presence and grading of gastro-oesophageal reflux was also examined. Twenty-eight children less than 2 years of age participated in the study. For assessment of variability, all subjects underwent two scintigraphic studies. For each study, the number of reflux episodes and gastric emptying half-times were recorded. The amount of reflux was graded according to the classification suggested by Blumhagen. Patients with grade 1 reflux were considered low-grade refluxers, while patients with grade 2 or 3 reflux were considered high-grade refluxers. The level of reflux for each patient was based on the highest reflux grade recorded in either study. Of the 28 patients, 19 had reflux in at least one study. Ten patients had high-grade and nine patients low-grade reflux. All patients but one with high-grade reflux had the same grade of reflux in both studies (90%). Of nine patients with low-grade reflux, three had the same grade in both studies. The mean half-time was significantly higher for high-grade than for low-grade refluxers (P < 0.05). For subjects with low-grade reflux, this value did not differ significantly from that of non-refluxers (P > 0.05). Our results show that patients with high-grade gastro-oesophageal reflux had prolonged gastric emptying. The inter- and intra-subject variability of gastric emptying in children appeared to be low. Reproducibility for the presence and grading of gastro-oesophageal reflux by the radionuclide method was good, with the highest value being for the diagnosis of high-grade gastro-oesophageal reflux.

Gastric Emptying↗
PubMed1998

Prediction of restenosis after successful percutaneous coronary angioplasty by dobutamine thallium-201 scintigraphy.

We evaluated the accuracy of dobutamine thallium-201 myocardial perfusion scintigraphy in predicting restenosis after successful percutaneous coronary angioplasty. Restenosis is one of the most important problems in patients who have undergone percutaneous coronary angioplasty. Exercise thallium-201 myocardial perfusion scintigraphy has been a well accepted non-invasive method to predict the restenosis of the dilated vessel after percutaneous coronary angioplasty, however, the role of thallium-201 myocardial perfusion using dobutamine, as a substitute for exercise in patients unable to exercise, in predicting restenosis is not well known. Therefore, 34 consecutive patients underwent dobutamine tomographic (single photon emission computed tomography) thallium-201 myocardial perfusion scintigraphy following a total of 37 successful angioplasties. No serious side effects during dobutamine infusion occured. The interval between percutaneous coronary angioplasty and scintigraphy ranged between 8 weeks to 2 years. All patients underwent control angiography within one month following myocardial perfusion scintigraphy. Sensitivity, specificity and accuracy of dobutamine myocardial imaging for predicting restenosis were 76%, 79% and 77%, respectively. Sensitivity and specificity related to the vascular territories were: left anterior descending artery 66-69%, left circumflex artery 75-100%, right coronary artery 83-66%, respectively. In conclusion, our findings demonstrating high accuracy of dobutamine myocardial single photon emission tomography for angiographic restenosis suggest its usefulness as a non-invasive tool in the follow-up of percutaneous coronary angioplasty patients.

Aged↗
PubMed1998

Are technetium-99m-labeled myocardial perfusion agents adequate for detection of myocardial viability?

The noninvasive assessment of myocardial viability in patients with coronary artery disease and depressed left ventricular function has proven clinically useful for identifying those patients with ischemic cardiomyopathy who benefit most from coronary revascularization. Thallium-201 (201Tl) imaging at rest has been the radionuclide imaging technique most often utilized for distinguishing viable myocardium from scar. However, new technetium-99m (99mTc) perfusion agents such as 99mTc-sestamibi and 99mTc-tetrofosmin have emerged as alternatives to 201Tl for imaging of regional myocardial perfusion. Whether these new agents, which have better physical properties for imaging with a gamma camera than 201Tl, are valid for use in assessing myocardial viability is still uncertain. Recent clinical studies have demonstrated that these agents, when imaged using quantitative SPECT, can identify patients with myocardial hibernation who exhibit improved regional systolic function following revascularization. Experimental laboratory studies have shown that the uptake of 99mTc-sestamibi and 99mTc-tetrofosmin in ischemic myocardium is only slightly lower than the uptake of 201Tl. These 99mTc-labeled agents remain bound intracellularly in mitochondria of viable myocytes under conditions of myocardial stunning and short-term hibernation, producing severe myocardial asynergy. With respect to determination of viability, the inferior wall region is at times problematic since attenuation of 99mTc-sestamibi and 99mTc-tetrofosmin is greatest in this area. Demonstration of preserved systolic thickening on ECG-gated SPECT images is indicative of viability in the instance of decreased regional 99mTc counts due to attenuation and not scar. Administration of nitrates prior to tracer injection improves the sensitivity for identifying viable myocardial segments using rest imaging with 99mTc-sestamibi or 99mTc-tetrofosmin. Thus, it appears that the new 99mTc perfusion imaging agents can be successfully employed for the determination of myocardial viability in the setting of severe regional dysfunction and chronic coronary artery disease. The greater the myocardial uptake of these agents in the resting state, the greater the probability of improved systolic function after coronary revascularization.

Animals↗
PubMed1998

Scintigraphic evaluation of healing response after heterograft usage for alveolar extraction cavity.

OBJECTIVE: Reconstruction of bone defects remains an important problem in oral and maxillofacial surgery. Restoration of defect sites with various grafting materials is a valuable approach to the solution of this problem. The aim of this study was to evaluate the effects of the use of heterografts on osteoblastic activity by means of a radionuclide technique. STUDY DESIGN: The postextraction alveolar cavities of impacted mandibular third molars on 22 patients were used as a healing model for this study. Granulated freeze-dried heterograft material of bovine origin was used on 11 patients; the other 11 patients constituted a control group. On each patient, three-phase bone scans were performed on postoperative days 7 and 28. RESULTS: Although dynamic and blood pool studies showed similar patterns with respect to the mean values of asymmetry ratios of operation sites to the contralateral sides for the 7th- and 28th-day scans, static-phase bone scans revealed that healing response through osteoinduction was more prominent in the study group than in the control group. A significant increase in the mean value of the ratio from the first scan to the second was observed on static images in the study group (first scan, 1.6 +/- 0.2; second scan, 2.0 +/- 0.5; p < 0.05). However, the same ratio failed to show any significant change in the control group (first scan, 1.5 +/- 0.2; second scan, 1.5 +/- 0.3; p > 0.05). CONCLUSION: Static-phase bone scintigraphy showed that when freeze-dried heterograft material is used to fill alveolar extraction cavities, it stimulates osteoblastic activity, which in turn leads to acceleration of the healing process and helps to maintain the linearity of bony structure. Moreover, radionuclide study can be used to evaluate the viability of freeze-dried heterografts in the 4th postoperative week, at which time no additional increase in perfusion resulting from surgical trauma was found in our series.

Alveolar Process↗