Compensation of Cross-Contamination in Simultaneous 201Tl/99mTc Myocardial Perfusion SPECT Imaging
Authors
Abstract:
Introduction: It is a common protocol to use 201Tl for the rest and 99mTc for the stress cardiac SPECT imaging. Theoretically, both types of imaging may be performed simultaneously using different energy windows for each radionuclide. However, a potential limitation is the cross-contamination of scattered photons from 99mTc and collimator X-rays into the 201Tl energy window. We used a middle energy window method to correct this cross-contamination. Material and Methods: Using NCAT, a typical software torso phantom was generated. An extremely thin line source of 99mTc activity was placed inside the cardiac region of the phantom and no activity in the other parts. The SimSET Monte Carlo simulator was used to image the phantom in different energy windows. To find the relationship between projections in different energy windows, deconvolution theory was used. We investigated the ability of the suggested functions in three steps: Monte Carlo simulation, phantom experiment and clinical study. In the last step, SPECT images of eleven patients who had angiographic data were acquired in different energy windows. All of these images were compared by determining the contrast between a defect or left ventricle cavity and the myocardium. Results: We found a new 2D kernel which had an exponential pattern with a much higher center. This function was used for modeling 99mTc down scatter distribution from the middle window image. X-ray distribution in the 201Tl window was also modeled as the 99mTc photopeak image convolved by a Gaussian function. Significant improvements in the contrasts of the simultaneous dual 201Tl images were found in each step before and after reconstruction. In comparison with other similar methods, better results were acquired using our suggested functions. Conclusion: Our results showed contrast improvement in thallium images after correction, however, many other parameters should be evaluated for clinical approaches. There are many advantages in simultaneous dual isotope imaging. It halves imaging time and reduces patient waiting time and discomfort. Identical rest/stress registration of images also facilitates physicists’ motion or attenuation corrections and physicians’ image interpretation.
similar resources
compensation of cross-contamination in simultaneous 201tl/99mtc myocardial perfusion spect imaging
introduction: it is a common protocol to use 201tl for the rest and 99mtc for the stress cardiac spect imaging. theoretically, both types of imaging may be performed simultaneously using different energy windows for each radionuclide. however, a potential limitation is the cross-contamination of scattered photons from 99mtc and collimator x-rays into the 201tl energy window. we used a middle en...
full textMyocardial perfusion SPECT: Perfusion quantification
Different software tools for quantification of myocardial perfusion SPECT (MPS) studies are routinely used. Several perfusion parameters can be computed automatically. Interpretation of the MPS should start with visual inspection of the rotating planar images, visual analysis of reconstructed SPECT slices and then quantitative analysis to confirm the visual impression. Quantification should be...
full textFilter selection for 99mTc-Sestamibi myocardial perfusion SPECT imaging [Persian]
Myocardial perfusion SPECT imaging with Tc99m-sestamibi is the most accurate non-invasive means of detecting coronary artery disease and assessing the severity of perfusion abnormalities in the patients with coronary stenosis. Though simple and straight forward the results produced by the technique is very much affected by the details being used. One of the main problems with the test, wh...
full textMyocardial Perfusion SPECT Imaging in Dextrocardia with Situs Inversus: A Case Report
Dextrocardia is a cardiac positional anomaly in which the heart is located in the right hemithorax with its base-to-apex axis directed to the right and caudad. Situs inversus is an autosomal recessive disorder that causes organs in the chest and abdomen to be positioned in a mirror image from their normal position. Dextrocardia may occur in isolation or as part of situs inversus. Similarly, sit...
full textEvaluation of myocardial perfusion and function after kidney transplantation by Gated SPECT myocardial perfusion scintigraphy
Introduction: The aim of this study was to evaluate the effect of successful kidney transplantation (KT) on myocardial perfusion and left ventricular function by both qualitative (visual) interpretation and semiquantitative parameters, using myocardial perfusion scintigraphy with gated-single photon emission computed tomography (gated-SPECT) in patients suffering from end-stage renal disease. ...
full textMy Resources
Journal title
volume 6 issue Issue 3,4
pages 58- 72
publication date 2009-12-01
By following a journal you will be notified via email when a new issue of this journal is published.
Hosted on Doprax cloud platform doprax.com
copyright © 2015-2023