Geant4 Based Monte Carlo Dose Calculation Engine for Radiation Therapy

Radiation dose calculation engine as a base for X-ray radiation treatment planning has been developed using Geant4 Monte Carlo toolkit and applying highly efficient voxel geometry with flexible material definition. With this engine we can easily customize flexible patient and beam modules, thus obtaining a common backend applicable to various radiation therapy planning systems. The engine was tested using the available experimental data for a water phantom and using the real CT data in X-ray therapies; the calculated doses were compared also against the MCNP5/X values. The results show that this Geant4 based radiation dose calculation engine has much higher computational speed than the models generated by an MCNP5/X-based treatment planning tool without any loss of accuracy. In addition, Geant4 is an open source code and applies no restrictions to the users.