Comparison of 180° and 360° arc data acquisition to measure scintigraphic parameters from gated SPECT myocardial perfusion imaging: Is there any difference?

INTRODUCTION: The aim of current study was to compare 180° and 360° data collection modes to measure end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) of cardiac system in gated myocardial perfusion tomography.
METHODS: Number of 39 patients underwent gated myocardial perfusion tomography. SPECT data of patients’ heart were acquired by 180°, 45° left posterior oblique to 45° right anterior oblique, and 360°to obtain EDV, ESV,EF and cardiac volume changes (V1, V2, V3, V4, V5, V6, V7 and V8) throughout each cardiac cycle.
RESULTS: Results of current study indicated that there were no significant difference between 180° and 360° angular sampling to measure EDV, ESV and EF in myocardial perfusion imaging. Pattern of cardiac volume changes during a cardiac cycle measured in by 360° and 180° scans were also the same. We also observed that there is no difference in EDV, ESV and EF of groups that performed exercise to induce stress with the group who experienced stress by dipyridamole.
DISCUSSION AND CONCLUSION: As there is no difference between 180°and 360° cardiac scan to measure EDV, ESV and EF, it is recommended to use half-orbit scan to study these parameters of cardiac system because it offers more comfort to patients and shorter scanning time.