二维电离室矩阵探测器的光子剂量学性能测试  

Test of dosimetric characteristics of 2-D matrix detector in photon beams

作　　者：翟贺争[1] 程金生[1] 丁艳秋[1] 郭朝辉[1] 齐伟华[2] 王军良[2] 刘立明[1] 刘雅[1] 张红红[1] 

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所 辐射防护与核应急中国疾病预防控制中心重点实验室,北京100088 [2] 军事医学科学院附属医院

出　　处：《中华放射医学与防护杂志》2015年第2期144-148,共5页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的 研究二维电离室矩阵探测器的剂量学特性,初步建立对其质量控制检测方法.方法 参照IEC 60731-2011报告对电离室剂量学指标的要求,在光子束（60Coγ射线,6、10和15 MVX射线）下,对二维矩阵探测器剂量测量重复性、稳定性、剂量率依赖性、剂量响应线性和电离室间响应一致性等剂量学指标进行测试.结果 二维矩阵探测器在不同能量射线下测量重复性＜0.3％,在60Co γ射线下测量6个月的稳定性＜0.5％;在不同能量X射线下,加速器出束10～250 cGy和60Co γ射线下剂量响应线性＜0.5％;在剂量率为200 ～ 600 MU/min下测量值最大偏差为0.87％;不同电离室间剂量响应偏差＜1％.结论 二维电离室矩阵探测器具有良好的剂量学特性;初步建立的质量控制检测方法具有可行性,并为放疗质量控制体系的建立提供理论依据.Objective To explore the dosimetric characteristics of 2-D matrix detector,and to establish method of quality control test.Methods By reference to IEC 60731-2011 requirements on ionization chamber dosimetric indicators,a range of dosimetric indicators of 2-D matrix detector were tested by using photon beams （60 Co γ-rays,6,10 and 15 MV X-rays）,including dosimetric repeatability,dose response linearity,dose rate dependency and dose measuring uniformity.Results The reproducibility of 2-D detector was less than 0.3%,and the medium-and long-term stability was less than 0.5%.The dose-response relationship was linear in the range of 10-250 cGy for 6,10,15 MV beams and 60Co photons.The dose linearity was less than 0.5%.The maximum deviation in measurement values was 0.87% in the dose rate range of 200 to 600 MU/min.The dose response derivations between different ionization chambers were less than 1.0%.Conclusions 2-D matrix detector has good dosimetric characteristics and the quality control testing method is feasible.

关 键 词：二维矩阵探测器 剂量学特性 质量控制 调强放射治疗 

分 类 号：R730.55[医药卫生—肿瘤]