A simulation to model position encoding multicrystal PET detectors

We have developed a simulation to model position encoding multicrystal detectors for positron emission tomography. The simulation is designed to treat the interactions of energetic photons in a scintillator, the geometry of the multicrystal array, as well as the propagation and detection of individual scintillation photons. The simulation is tested with a model of the EXACT HR PLUS block detector manufactured by Siemens-CTI. Position and energy responses derived from the simulation are compared to measured ones. Line-spread-functions, for four columns of crystals, are reproduced with an accuracy of ±0.5 mm. The crystal-by-crystal photopeak pulse heights and FWHMs are also predicted within a range of ±14%, and _-6⁺⁹%, respectively