Purpose: To develop an extension of medical imaging devices for the TOPAS Monte Carlo (MC) system
Methods: MC methods have been extensively used to simulate imaging systems, but there have so far been no examples for the TOPAS MC. We designed easily modifiable classes for the detector geometries, sources, and scorers in PET, SPECT, and CBCT systems. The output file is scored in CASToR (Customizable and Advanced Software for Tomographic Reconstruction) format that can directly be processed for image reconstruction using CASToR.
Results: We developed TOPAS for Imaging, an extension of TOPAS designed to generate the geometries of PET, SPECT, and CBCT and record their measurements of simulated radioactive sources for reconstruction in CASToR. First comparisons to experimental data for validating the PET system will be presented.
Conclusion: TOPAS for Imaging promises to advance our understanding of imaging systems by enabling researchers to have more platforms for simulating their systems.
Funding Support, Disclosures, and Conflict of Interest: This project was funded by the AAPM, MIT, and NIH.