TOF capability evaluation on a panel PET for human body imaging

Abstract

Due to its unique structure, parallel panel configuration may lead to novel applications for positron emission tomography (PET). The major challenge of panel PET imaging is the limited angle problem, to which the time-of-flight (TOF) information seems to be a promising solution. This work investigated the required TOF capability of a panel PET design, which has a feasible size of field of view (FOV) for human torso. Such a system's corresponding angular coverage can vary from 70 to 102 degrees. The recovery ability of small lesions was assessed, and the contrast recovery coefficient (CRC) and signal-to-noise ratio (SNR) were analyzed, with a full ring PET as the benchmark system. We also varied the timing resolution and the distance between panels, to evaluate their impacts on image quality. Encouraging results were obtained in simulation study. Distortions and artifacts caused by the limited angular coverage were greatly reduced with timing resolutions better than 300 ps. The recovery ability of small lesions in most part of FOV was desirable. Meanwhile, varying panel distance in the range of 25 to 45 cm seemed to have trivial influence, when timing resolution was fixed at 300 ps. That means that such changes of panel distance might not affect the requirement on TOF capability, allowing more flexibility in panel PET's design and applications.