ArticlePrerequisite for projection data and reconstruction not to cause truncation artifacts in myocardial perfusion single- photon emission computed tomography: Phantom study
Masahisa Onoguchi* , Kotatsu Tsuboi, Mitsuo Sugimoto, Takayuki Shibutani, Akio Nagaki and Akihiro Kikuchi
Myocardial perfusion single-photon emission computed tomography (SPECT) studies are used widely in the evaluation and diagnosis of coronary artery disease. Although one method to improve the spatial resolution is zooming acquisition, truncation artifact occurs in reconstructed tomographic images. To date, it is unclear how much truncation (area and radioactivity) of projection data would affect myocardial image. The aim of this study is to investigate the combination of truncated projection data conditions and image reconstruction methods that do not require re-examination. We used a cylindrical and anthropomorphic torso phantom with 99mTc solution, and shifted the projection data to simulate truncated liver tissue. SPECT images were acquired using a dual-detector gamma camera and reconstructed using filtered back projection (FBP) and ordered subset expectation maximization (OSEM) to create transverse images. We compared truncation data and reference data (none truncated projection data) for count profile curve, uniformity, myocardial counts, and % uptake. Our findings indicate that prerequisite for truncation data and image reconstruction method would not affect the myocardial image, when the area of truncation was < 17.5% and the count of the truncation portion was lower than that in the myocardium using FBP.
Myocardium, single-photon emission computed tomography, filtered back projection.