IMRT treatment Monitor Unit verification using absolute calibrated BEAMnrc and Geant4 Monte Carlo simulations

17th International Conference on the Use of Computers in Radiation Therapy

物理学;计算机科学

Oborn, B.M.^1,2 ; Williams, M.^1,2 ; Bailey, M.^1,2 ; Carolan, M.G.^1,2

Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong NSW 2500, Australia^1

Centre for Medical Radiation Physics, University of Wollongong, Wollongong NSW 2522, Australia^2

关键词: Calibrated monte carlo;    Head and neck;    IMRT delivery;    Intensity-modulated radiation therapy;    Monitor units;    Monte Carlo codes;    Phantom dose;    Planning systems;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/489/1/012020/pdf
DOI  :  10.1088/1742-6596/489/1/012020

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

Intensity Modulated Radiation Therapy (IMRT) treatments are some of the most complex being delivered by modern megavoltage radiotherapy accelerators. Therefore verification of the dose, or the presecribed Monitor Units (MU), predicted by the planning system is a key element to ensuring that patients should receive an accurate radiation dose plan during IMRT. One inherently accurate method is by comparison with absolute calibrated Monte Carlo simulations of the IMRT delivery by the linac head and corresponding delivery of the plan to a patient based phantom. In this work this approach has been taken using BEAMnrc for simulation of the treatment head, and both DOSXYZnrc and Geant4 for the phantom dose calculation. The two Monte Carlo codes agreed to within 1% of each other, and these matched very well to our planning system for IMRT plans to the brain, nasopharynx, and head and neck.