摘要
目的对TomoTherapy HI-ART加速器剂量输出的稳定性进行检测和评价。方法利用A1SL电离室、矩形固体水模体与圆柱形固体水模体,参照美国医学物理学会TG-148号报告,对TomoTherapy HI-ART加速器质控规程中静态剂量输出、动态剂量输出、射线质稳定性进行检测,并对结果进行分析。结果静态剂量输出结果偏差平均值为(-0.6±1.1)%,有89.1%的数据在±2%的允许偏差范围之内,数据分布无明显规律。动态剂量输出结果偏差平均值为(1.0±1.1)%,有87.1%的数据在±2%的允许偏差范围之内。射线质较为稳定,偏差平均值为(-0.01±1.26)%,80%的结果在±1%的偏差范围之内,96%的结果在±2%的允许偏差范围之内。结论 TomoTherapy HI-ART加速器剂量输出稳定性略低于常规加速器,剂量输出易发生波动,因此每日对其输出量进行系统检测十分重要。
Objective To test and assess the output constancy of TomoTherapy HI-ART. Methods Ac- cording to TG-148 of American Association of Physicists in Medicine （AAPM） report and by using A1SL ionization chamber, slab solid water phantom, and cheese phantom, we tested and analyzed the constancy of static output, ro- tational output, and energy of TomoTherapy HI-ART. Results The average output variation was （ - 0. 6 ± 1.1 ） % for the static condition, and 89. 1% of the collected output data were within the action level of ±2%. The aver- age variation of rotational output was （ 1.0 ± 1.1 ） % , and 87. 1% of the collected data were within ± 2%. An average energy variation was （ - 0. 01 ±1.26） %, and 80% data were within ＋ 1% and 96% data within ± 2%, which showed good constancy and reproducibility. Conclusions The output constancy of TomoTherapy HI-ART is less stable than conventional Linac, so it is important to test static and rotational output everyday to ensure the accuracy.
出处
《协和医学杂志》
2013年第4期404-407,共4页
Medical Journal of Peking Union Medical College Hospital
