Measurement and calculation of X-ray small fields′ data for Varian accelerator
WANG Xue-tao*, CHEN Shao-wen, DAI Zhen-hui, ZHU Lin, LIU Xiao-wei
*Department of Radiation Oncology, Guangdong Provincial Hospital of TCM, Guangzhou 510120,China Corresponding author:LIU Xiao-wei,School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275,China
Abstract：Objective The beam data is compared with those obtained from Monte Carlo (MC)simulation and measurement to investigate their feasibility and reliability for X-ray small fields. Methods The beam data, including the total scatter factor (Scp), percentage depth dose (PDD) was acquired by measurement and calculation with the field size ranging from 0.5 cm×0.5 cm to 10 cm×10 cm. The results were compared and analyzed. Results All the data is most consistent for the fields size of ≥3.5 cm×3.5 cm, but they are obvious different for the fields size of ≤3.0 cm×3.0 cm. The measurements seem to reliable using the chambers of CC04 and CC13 for the fields size of ≥2.0 cm×2.0 cm. Conclusions It is demonstrated that the accurate measurements and calculations of Scp and PDD can be obtained for the fields size of ≥2.0 cm×2.0 cm, but they needed more researches for the smaller fields.
WANG Xue-tao*,CHEN Shao-wen,DAI Zhen-hui et al. Measurement and calculation of X-ray small fields′ data for Varian accelerator[J]. Chinese Journal of Radiation Oncology, 2012, 21(6): 557-559.
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2012, Vol. 21 
