A High Count-Rate and Depth-of-Interaction Resolving Single-Layered One-Side Readout Pixelated Scintillator Crystal Array for PET Applications

Abstract

Organ-specific, targeted field-of-view (FoV) positron emission tomography (PET)/magnetic resonance imaging (MRI) inserts are viable solutions for a number of imaging tasks where whole-body PET/MRI systems lack the necessary sensitivity and resolution. To meet the required PET detector performance of these systems, high count-rates and effective spatial resolutions on the order of a few mm, a novel two-axis patterned reflector foil pixelated scintillator crystal array design is developed and its proof-of-concept illustrated in-silico with the Monte Carlo radiation transport modeling toolkit Geant4. It is shown that the crystal surface roughness and phased open reflector cross-sectional patterns could be optimized to maximize either the PET radiation detector's effective spatial resolution, or count rate before event pile up. In addition, it was illustrated that these two parameters had minimal impact on the energy and time resolution of the proposed PET radiation detector design. Finally, it is shown that a PET radiation detector with balance performance could be constructed using ground crystals and phased open reflector cross-sectional pattern corresponding to the middle of the tested range.