Effects of setup errors on dosimetric verification of stereotactic body radiotherapy plan(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第8期
- Page:
- 869-873
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Effects of setup errors on dosimetric verification of stereotactic body radiotherapy plan
- Author(s):
- LI Yucheng1; 2; CHEN Weijun2; SHAN Guoping3; ZHAO Kai3; SHI Guodong3; SHAO Kainan3; LI Pu3; YANG Yiwei3; CHEN Xiang1; CHENG Pinjing1
- 1. Shool of Nuclear Science and Technology, University of South China, Hengyang 421001, China; 2. Department of Radiotherapy, Zhejiang Provincial People’s Hospital, Hangzhou 311400, China; 3. Department of Radiation Physics, Zhejiang Cancer Hospital, Hangzhou 311400, China
- Keywords:
- ; Keywords: stereotactic body radiotherapy; setup error; dosimetric verification; gamma passing rate; lung cancer
- PACS:
- R730.55
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.08.001
- Abstract:
- Abstract: Objective To analyze the effects of setup errors on dosimetric verification of stereotactic body radiotherapy (SBRT) in patients with lung cancer. Methods SBRT plans were designed for 14 patients with lung cancer, and then transplanted to Delta4 phantom for dose calculation. The irradiation was implemented on Varian Trilogy linear accelerator. The setup errors were simulated by moving the treatment couch to the left (+X), right (-X), head (+Y), foot (-Y), ventral (+Z), back (-Z) by 1, 3 and 5 mm. The relationships of gamma passing rate in the 6 directions were analyzed for verifying the effects of setup errors on dose verification under different gamma criteria (3%/3 mm, 2%/2 mm). Results Only when the setup error was 1 mm, the differences in the right and foot directions had no statistical significance as compared with original plan under the gamma criterion of 2%/2 mm (P>0.05), and no statistical significance was found in all directions under the gamma criterion of 3%/3 mm (P>0.05). When the setup error was 1 mm, the gamma passing rates were all greater than 90% under the two gamma criteria (3%/3 mm, 2%/2 mm). When the setup error was 3 mm, only the gamma passing rates in the direction of right, foot, ventral and back were greater than 90%. When the setup error was 5 mm, the gamma passing rates were all less than 90% under the two gamma criteria (3%/3 mm, 2%/2 mm), and the total passing rate of head direction were decreased to (35.29±8.40)%. Conclusion Setup error has great effects on the dosimetric verification of SBRT plan. The finer the gamma criteria are, the more obvious the effects of setup error on the gamma passing rate are.
Last Update: 2018-07-26