The analyzing to the effects of high-order scattered X-ray to dose calculation in radiotherapy
BAI Yan-ling*, XIAO Xue-fu, SHAO Wen-cheng
*Department of Radiation Physics, Third Hospital of Harbin Medical University, Harbin 150081, China Corresponding author:XIAO Xue-fu, Department of Radiation Metrology, China Institute of Atomic Energy, Beijing 102413,China.
Abstract：Objective To analyze the effects of high-order scattered X-ray in dose calculation in radiotherapy, to resolve the problem of correcting the dose contribution of secondary and high-order scattering X-ray to the primary scattered X ray, and to provide a support for photon fast dose calculation method of Monte Carlo. Methods By the theory of cross-section in interaction between X-ray with material and Monte Carlo calculating results, to analysis the relative importance of primary scattered X-ray, secondary and high-order scattered of X-ray in dose calculation. Results The contribution of secondary and high-order scattered X-ray to dose calculation was very small, it can be corrected to the primary scattered X-ray with a correction factor. Conclusions The results show that we can obtain a precise dose calculation for radiotherapy by only to tracking the contribution of primary X-rays and primary scattering X-ray, so, to establishing the database for primary scattering X-ray by Monte Carlo methods is important for fast dose calculation of Monte Carlo method.
BAI Yan-ling*,XIAO Xue-fu,SHAO Wen-cheng. The analyzing to the effects of high-order scattered X-ray to dose calculation in radiotherapy[J]. Chinese Journal of Radiation Oncology, 2012, 21(4): 384-387.
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2012, Vol. 21 
