Validation of SORTEO Monte Carlo simulations for the geometry of the Concorde MicroPET R4 system

PET-SORTEO is a Monte Carlo-based simulator that enables the fast generation of realistic PET data for the geometry of the ECAT EXACT HR+ scanner. In order to address the increasing need for simulation models for animal PET imaging, our aim is to adapt and configure this simulation tool for small animal PET scanners, especially for the three widely distributed systems manufactured by CTI-Concorde Microsystems (R4, P4 and Focus). Our goal is to propose a simulation model that will allow producing realistic rodent images in order to evaluate and optimize acquisition and reconstruction protocols. The first step presented in this study was to validate SORTEO against the geometry of the R4 system and to demonstrate the feasibility of simulating realistic activity distributions in mice in a short computation time. This validation of the simulation model was carried out against actual measurements performed on the R4 scanner at the Montreal Neurological Institute