Scatter Fraction and Noise Equivalent Count Rate performance of the Siemens Biograph™ 6 Positron Emission Tomography (PET) scanner: Comparison of a GATE Monte Carlo simulation model with the NEMA NU 2-2001 protocol experimental data

Abstract

GATE (Geant4 Application for Tomographic Emission) is a Monte Carlo simulation platform, based on the Geant4 Monte Carlo code, suitably developed for Nuclear Medicine applications, e.g. for Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) system and dosimetry simulations. GATE is distributed by the OpenGATE collaboration and provides the ability of modelling time-dependent phenomena, such as geometry element movements and source decay kinetics, allowing the simulation of time curves under realistic acquisition conditions. The purpose of this paper was to validate a GATE model for the simulation of the Siemens PET Biograph™ 6 scanner. This three-dimensional GATE model simulated 24336 LSO (Lutetium Oxyorthosilicate) detectors grouped into 144 blocks in accordance with the vendor’s specifications. The scatter phantom, used by the NEMA NU 2-2001 performance evaluation protocol, was also modelled within GATE framework, allowing us to simulate scatter fraction and count rate performance measurements. GATE simulation results were compared with experimental data, obtained in accordance with the NEMA NU 2-2001 protocol. Deviation of less than 3% was obtained for the scatter fraction and less than 9% for the noise equivalent count rate.