Comparison of thallium-201 single-photon emission computed tomographic scintigraphy with intravenous dipyridamole and arm exercise ☆
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Thallium-201 ( Tl-201) is a radiopharmaceutical used for scintigraphy, primarily of the myocardium. The element thallium is treated by the body as an analog of …
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Rotating gammacamera tomography has beenshownto bethe best imagingtechnique generallyavailable for thallium-201 scintigraphy ofthe myo-cardium.'61-8 Theuse of …
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Thallium-201 tomographic perfusion studies after pharmacologic vasodilation were performed in seven children (aged 2 years 8 months to 8 years 7 months), 3 to 20 months after the acute stage of the disease. In all patients coronary aneurysms were seen on cross-sectional echocardiograms. The scintigrams of six children showed no significant ...
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It was the purpose of this study to compare intravenous dipyridamole and arm exercise thallium-201 single-photon emission computed tomographic (SPECT) …
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Thallium-201 is distributed actively into myocardial cells, whereas technetium-based products are distributed passively depending on blood flow and myocardial viability. These radiotracers are injected when the heart is stressed, either by exercise or pharmacologically. The uptake of radiotracer indicates areas of perfusion and viable …
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A comprehensive method is described for quantification of the relative 3-dimensional distribution of TI-201 in the myocardium, following stress and subsequent washout. The method uses maximal-count circumferential profiles of well-defined long- and short-axis tomograms to determine the 3-dimensional distribution of TI-201; it then maps this ...
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A new automated edge detection program has been developed to estimate left ventricular mass from single-photon emission computed tomographic (SPECT) thallium-201 images of patients. Left ventricular (LV) mass was measured from contrast angiograms in 21 patients and was compared with LV mass estimated from thallium-201 …
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The U.S. Department of Energy's Office of Scientific and Technical Information
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All patients underwent thallium imaging 15 min, 4 h and late (18 to 72 h) after stress as part of the preintervention thallium-201 scintigram. In a total of 201 tomographic myocardial segments with definite post-stress thallium-201 perfusion defects in which the relevant coronary arteries were subsequently successfully reperfused, the 4 h ...
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Key Words: thallium-201 reverse redistribution • myocardial revascularization ° viable myocardium The phenomenon of reverse redistribution, defined tomographic imaging. 1-9 The presence of reverse redis- as a thallium-201 defect being present or more promi- tribution has been associated with either severe coronary nent on redistribution ...
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Possible Protocols for Thallium-201 Viability Imaging: Stress Protocols. In our department imaging is performed with a tomographic triple-head gamma camera, equipped with low-energy high-resolution (LEHR) collimators. Each detector rotates over a 120° orbit acquiring 24 projections per head, 30 s
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A new automated edge detection program has been developed to estimate left ventricular mass from single-photon emission computed tomographic (SPECT) thallium …
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Objective: The correlation between thallium-201 (201TI) uptake, semiquantitative choline-containing compound values measured by proton magnetic resonance spectroscopy (1H-MRS), and Ki-67 labeling indexes (LIs) was investigated in three gangliogliomas. Methods: The early and delayed 201TI indexes were calculated as the ratio of tumor to normal …
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Abstract. Coronary arteriolar vasodilation may provoke redistribution of flow to collateral-dependent jeopardized myocardium. To assess the physiologic significance of collaterals, 80 consecutive post-infarction patients (age 58 +/- 8 years) underwent vasodilation-redistribution thallium-201 tomographic imaging after administration of …
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The ability of exercfse thallium-201 tomographic imaging to predict the presence of feft main or 3- vessel coronary artery disease (CAD) was exam- ined in 688 patknts who underwent both exercise thallium-201 testbtg and coronary angiography. Qgnffkant dffferences existed for multiple vari-
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To determine whether a new approach to interpretation could improve the accuracy of thallium-201 single photon emission computed tomography (SPECT) for detection of …
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Thallium-201 tomographic images were obtained within 10 min of the injection of the radiopharmaceutical using a 180° circular orbit, from 45° right anterior oblique to 45° left posterior oblique, 32-frame step-and-shoot, 50 s/frame, with the patient in the supine position. Redistribution imaging was performed 4 to 6 h later using the same ...
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Exercise thallium-201 imaging using single-photon emission computed tomography (SPECT) was evaluated in 154 patients with angiographically documented coronary artery disease (CAD) and in 25 normal subjects. Of the 154 patients with CAD, 134 (87%) had abnormal thallium images. By contrast, only 77 (5 …
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Adenosine thallium-201 scintigraphy provides diagnostic information similar to that of exercise scintigraphy, although values for defect sizes are greater with adenosine. ... Effect of exercise level on the ability of thallium-201 tomographic imaging in detecting coronary artery disease: analysis of 461 patients. J Am Coll Cardiol, 14 ...
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Cramer MJ, Verzijlbergen JF, Van der Wall EE, Niemeyer MG, Zwinderman AH, Ascoop CA, Pauwels EJ. Head-to-head comparison between technetium-99m-sestamibi and thallium-201 tomographic imaging for the detection of coronary artery disease using combined dipyridamole-exercise stress. Coron Artery Dis. 1994 Sep; 5 (9):787–791. [Google Scholar]
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Conclusions: Dipyridamole thallium-201 tomographic imaging has good sensitivity () in detecting esophagogastric mucosal erosions, but its poor specificity (33-57%) results in an unacceptable accuracy as a screening test. Additionally, the cost of radiopharmaceuticals requires that sensitivity and specificity be at least equal to that of ...
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Fintel et al. (3) report that the use of 1.5 to 2 mCi of thallium-201 generally produced "satisfactory" initial poststress and 4 h redistribution images for visual analysis. …
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The theory and techniques of planar and tomographic thallium-201 myocardial imaging are described, together with their application in the diagnosis of coronary artery disease. The prognostic value of thallium imaging is also examined. Myocardial infarct imaging with 99mTc pyrophosphate is described, and clinical indications are reviewed.
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Abstract. A comprehensive method is described for quantification of the relative 3-dimensional distribution of TI-201 in the myocardium, following stress and …
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To determine the relation between regional myocardial perfusion and regional wall motion in humans, tomographic thallium-201 imaging and two-dimensional echocardiography at rest were performed on the same day in 83 patients 4 to 12 weeks after myocardial infarction. Myocardial perfusion and wall motion were assessed …
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To determine whether a new approach to interpretation could improve the accuracy of thallium-201 single photon emission computed tomography (SPECT) for detection of left anterior descending coronary artery disease in patients with left bundle branch block, 69 patients were evaluated. Forty-four had …
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Abstract. Objectives. We compared dipyridamole technetium-99m (Tc-99m) tetrofosmin and thallium-201 (Tl-201) single-photon emission computed tomographic (SPECT) imaging with respect to the detection rate of perfusion abnormalities in 26 patients with angiographic coronary artery disease (CAD).
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The U.S. Department of Energy's Office of Scientific and Technical Information
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Gibson C, Laird E, Williams E, Rajathurai A, Mittra B and Rankin D (1985) New technique for showing the relation of tomographic myocardial …
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Visual versus quantitative analysis of thallium-201 tomography. Although the results of visual analysis by trained observers as reported by Fintel et al. (3) are likely to remain pivotal in the overall evaluation of tomographic thallium-201 images, objective quantitative analysis methods for SPELT have been developed and validated (18,22-24).
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Thallium-201 single-photon emission computed tomographic and proton magnetic resonance spectroscopic characteristics of intracranial ganglioglioma: three technical …
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Perfusion images can be recorded with planar or tomographic single-photon or positron imaging techniques, using radiopharmaceuticals that are extracted and retained for a variable period of time by the myocardium. ... When 201 Tl is used as the radiopharmaceutical, ... the dose of thallium may be 140 MBq (4 mCi) for each injection …
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Background Tetrofosmin is a new technetium 99m-labeled myocardial perfusion agent that has demonstrated favorable imaging characteristics in recent clinical trials. However, it is not certain whether 99mTc-tetrofosmin compared with thallium 201 would underestimate myocardial viability in regions with left ventricular dysfunction. Methods To this end 15 …
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Quantification of thallium myocardial studies affords the advantage of objectivity over visual analysis. Moreover, comparison of patient profiles to normal limits gives nonexpert readers a sense of confidence for interpreting these studies. Quantification of the washout rate from planar scintigrams aids in overcoming any lack of contrast. Tomography has excellent …
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A comparison of the tomographic technique and standard (parallel-hole collimatlon) scintigraphy was performed using 65 patients (Group I), 23 without and 42 with angiographically demonstrated coronary arterial stenosis (greater than 70 percent luminal narrowing) who were undergoing stress thallium-201 imaging.
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