Abstract

The goal of this simulation study is to assess and compare Parallax error with different scintillator crystals in Positron Emission Tomography (PET). For this simulation study, we use the GEANT4 Application for Tomographic Emission (GATE). The crystals which act as simulators in this study are LSO, GSO, BGO, and LYSO. In this work, we simulate a PET scanner with two rings and hexagonal geometries. Full ring PET scanner which consists of 26 detectors block where each block consists of 96 crystal blocks. In each crystal block, there are 25 crystals. For hexagonal geometry in each head, we simulate 620 blocks, each one consisting of 25 crystals. In both the geometries, a cylindrical-shaped pancreas phantom is used for this simulation. We set 350 KeV thresholds and 750 KeV upholders. The coincidence window for both geometries is 10 nanoseconds. Also, we evaluate the effect of gantry rotation on parallax error. To extract the parallax of each case, we analyze simulation output via ROOT Tree.