Preliminary investigation of the impact of Axial Ring Splitting on Image Quality for the Cost Reduction of Total-Body PET

Abstract

Recently, the first TB-PET scanner was unveiled and the initial results were nevertheless impressive. However, the cost of a TB-PET scanner is prohibiting for many institutions around the globe. Therefore here we investigate a cost reduction strategy incorporating a flexible detector arrangement. The proposed arrangement increases the axial field of view while keeping the overall cost at lower levels. We propose the axial ring splitting, which separates the full rings, of a compact PET scanner, to an expanded scanner with rings having only even or only odd numbered detectors. In this paper some preliminary performance results using Monte Carlo simulations, will be presented. In this comparison three configurations were considered (a) full rings PET (b) half-split rings TB-PET (c) full-split rings TB-PET. In addition in this investigation the effects of a varying coincidence window are demonstrated. The preliminary results suggest that Config.A demonstrated the highest Noise Equivalent count rate using either a fixed or a varying coincidence window. The main reasons were the absence of gaps and better handling of background radiation. However, reconstructed images for a single bed, from a whole body acquisition, suggested that due to the longer single bed acquisition of the full-split rings geometry the images present better noise properties.