Implementation and validation of a planar detector module for SimSET

The authors have developed a Monte Carlo planar detector module for their “Simulation System for Emission Tomography” (SimSET) package. The module tracks gamma rays through multiple-layer rectangular detectors. Each layer of the detector can be designated as active (scintillating) or inactive, allowing detector assembly elements and/or graded absorbers to be simulated in addition to scintillation crystal. For each gamma ray, the module outputs either a list of gamma ray interactions, giving location and energy deposited, or total energy deposited and an energy-weighted centroid over the active layers. The module can be used with or without collimation. Without collimation, using two detector heads, dual head coincidence imaging can be simulated. The binning module has been extended to support binning for the 3DRP, SSRB, and MSRB PVI reconstruction algorithms. The module has been tested extensively to validate the algorithms and implementation. The authors present the module design along with the validation work and performance characteristics