Absorbed Dose Calculation for I-131 Radiotherapy by Combining Monte Carlo Simulation of Electrons and S Value Convolution of Photons

Purpose

Accurate patient-specific absorbed dose estimation is important for radionuclide therapy, but its routine clinical use is limited by the high computational cost of full Monte Carlo simulations. Voxel S value (VSV)-based convolution methods are efficient, but their accuracy may decrease in heterogeneous media, especially for short-range electrons. This study presents a practical hybrid dose calculation framework for I-131 therapy to balance accuracy and efficiency.