Development and Validation of a GATE Simulation Model for the LabPET Scanner

A three-dimensional (3D) of the LabPET scanner has been newly developed by means of GATE (Geant4 application for tomographic emission) with the purpose of carrying out a detailed study of the system´s performance. The accuracy of this model was examined by comparing simulated, theoretical and experimental results obtained with LabPET for different performance features including detection efficiency, sensitivity, count rates, photoelectric probability, phoswich detector energy resolution and intrinsic spatial resolution. An agreement of 95% for singles count rates, 96% for detection efficiency and 90% for absolute sensitivity was obtained between simulations and measurements. Also, an agreement of >97% for photoelectric fraction, > 96% for radial intrinsic resolution and >93% for axial intrinsic resolution, was obtained between simulations and the theoretical calculations. In conclusion, the achieved results support the accurate modeling of LabPET with GATE.