Effect of CT image-based voxel size on EGSnrc Monte Carlo dose calculation

Empirical and semi-empirical routine dose calculation algorithms have been commonly selected for the radiation treatment planning system, though they have limited accuracy for dose distribution calculation. The Monte Carlo method can precisely give the above distributions, but its long CPU time affects clinic application. This paper presents a calculation instance. Namely, based on the CT data of a patient's head and neck, the Monte Carlo code is used to investigate the effect of different voxel sizes on the accuracy of dose distribution calculation and the computing time.