Abstract
3098
Introduction: Myocardial perfusion quantification with 15O-labelled water PET is used commonly. However, the use of high activity and performing reconstruction with time of flight (TOF) influence the accuracy of the quantification. The purpose of this study was to compare the difference between a-PET and d-PET on phantom study with 15O-labelled water.
Methods: A-PET (Gemini-TF, Philips Healthcare) and d-PET (Vereos, Philips Healthcare) were used for the examination. 15O-labelled water (800kBq/cc) was inserted in myocardium and left ventricle of the torso phantom. Immediately, 90 minutes dynamic scan was performed and the acquisition data were divided to 90 frames. For image instruction, all correction (delay correction, attenuation, random, scatter) were applied. We measured the activity of myocardium and left heart ventricle with P-mod analysis.
Results: There were significant differences between a-PET and d-PET with high activity of 15O-labelled water. With d-PET, there was no difference in the measured activity when the true activity increased. In 700kBq/cc of the true activity, the mismatch of measured activity was 2% compared to 100kBq/cc. However, with a-PET, as the true activity increased, the measured activity steadily declined. The mismatch of measured activity was 3%. Furthermore, when performing reconstruction with TOF, this tendency was seen more apparently. The mismatch of measured activity was 6%. By contrast, with d-PET, performing reconstruction with TOF did not influence the mismatch of 2% in the measured activity even in 700kBq/cc of the high true activity.
Conclusions: The results of this study suggest that there is the advantage of measurement in high activity on 15O-labelled water with d-PET and performing reconstruction with TOF influence the accuracy of the measured activity.