Comparison of 180° and 360° data collection in thallium-201 imaging using single-photon emission computerized tomography (SPECT)
Using the SPECT system with two gamma cameras, the effects of 180° data collection without attenuation correction were compared against 360° collection with attenuation correction, using phantoms and patients. With a heart phantom in a chest phantom, Tl-201 activities simulating `normal myocardium', `ischemia', `infarction', and `background' were placed in object contrast ratios (with respect to background) of 5.0, 2.0 and -1.0, respectively. The 180° data gave image contrast ratios of 1.6, 0.2, and -0.8, and the 360° data gave ratios of 1.5, 0.8, and -0.3, respectively. Uniform activity throughout the heart gave similar image contrast with both data-collection methods, but there was more variability with the 180° collection than with 360° collection