In intensity-modulated radiotherapy,how to choose the radiation cut-off radius is very important to the precision and computational efficiency in convolution based dose calculation.

• 在调强放射治疗中,为了保证剂量计算的精确度和避免不必要的时间耗费,采用微分卷积积分方法进行剂量计算时,选择一个合适的散射截止半径是非常重要的。