GPU accelerated internal dose Monte Carlo simulation in 18F-FDG PET imaging

Estimation of radiation dose from diagnostic or therapeutic radiopharmaceuticals in humans has drawn great interests. A graphics processing units based (GPU-based) positron and photon coupling transport code was developed for rapid calculation of the internal irradiation dose map. PENELOPE random hinge model was used to calculate the multi-scattering problem. More than 90% of the organ dose differences compared with GATE are within 1%. The average organ dose difference is 0.651%. The calculation time for 1E8 particles is only 321 s, and the calculation time for 1E7 particles is only 35 s, which is only 0.1% of GATE. simulation accuracy and acceleration efficiency of this study are both significantly improved compared with other GPU-based internal dosimetry Monte Carlo simulation code. This work can help to develop a more patient-specific, accurate, efficient way to improve the speed of PET/CT dosimetry Monte Carlo simulation.