放射治疗千伏级图像引导系统的辐射剂量研究  

Study on radiation dose of kV image-guided system in radiotherapy

作　　者：付娟 孟慧鹏 王克强[2] 张若辉 段敬豪 张艳龙 丁红军[2] 孙倩[2] 李西川 FU Juan;MENG Hui-peng;WANG Ke-qiang;ZHANG Ruo-hui;DUAN Jing-hao;ZHANG Yan-long;DING Hong-jun;SUN Qian;LI Xi-chuan(Characteristic Medical Center of PAP,Tianjin 300162,China;School of Precision Instrument and Opto-electronics Engineering,Tianjin University,Tianjin 300072,China;College of Life Sciences,Tianjin Normal University,Tianjin 300387,China)

机构地区：[1]武警特色医学中心,天津300162 [2]天津大学精密仪器与光电子工程学院,天津300072 [3]天津师范大学生命科学学院,天津300387

出　　处：《医疗卫生装备》2020年第2期52-56,共5页Chinese Medical Equipment Journal

摘　　要：目的:探讨放射治疗千伏级图像引导系统各扫描协议产生的辐射剂量,分析图像引导过程中产生的额外辐射剂量可能存在的潜在风险。方法:基于EGSnrc程序准确建模千伏级图像引导系统(瓦里安公司OBI)的基础上,对图像引导系统各扫描协议的辐射剂量进行模拟,模体采用国际放射防护委员会(International Commission on Radiological Protection,ICRP)发布的成年男女标准模体(ICRP 100)。2种模体的组织当量剂量根据ICRP 103号报告推荐的方法计算,最终得到千伏级图像引导系统各扫描协议下辐射剂量的有效剂量。结果:标准剂量头、低剂量胸、盆腔3种扫描协议下,单次图像引导男模体的组织当量剂量分别为0.85、3.26、4.51 mSv,女模体的组织当量剂量分别为1.14、3.80、6.57 mSv;3种扫描协议的有效剂量分别为0.48、4.25、6.44 mSv;单个组织的平均辐射剂量最大值出现在膀胱中(盆腔模式),其值达到了37.56 mGy。结论:多次图像引导产生的累积辐射剂量有潜在致癌风险,临床应用中需引起重视。Objective To investigate the radiation dose produced by scanning protocols of kV image-guided system in radiotherapy and to analyze the potential risk of additional radiation dose generated during image-guided.Methods Based on the accurate modeling of kilovolt image guidance system(Varian OBI)by EGSnrc program,the radiation dose of each scanning protocol of image guidance system was simulated.The adult male and female standard phantoms(ICRP 100)issued by International Commission on Radiological Protection(ICRP)were adopted.According to the recommended method in ICRP 103 report,the organ equivalent doses of the two phantoms were calculated,and the effective dose of each scanning protocol radiation dose of kV image-guided system was finally obtained.Results The tissue equivalent doses of male and female phantom were 0.85/1.14 mSv,3.26/3.80 mSv and 4.51/6.57 mSv respectively in three scanning modes of head,low dose chest and pelvis of standard dose guided by single image.The effective doses of the three scanning protocols were 0.48,4.25 and 6.44 mSv,respectively.Maximum value in average radiation dose of a single tissue appeared in the bladder(pelvic mode)and reached 37.56 mGy.Conclusion The cumulative radiation dose produced by multiple image-guided system has potential cancer risks,and more attention has to be paid to its clinical application.

关 键 词：图像引导 MONTE CARLO模拟 辐射剂量 锥形束CT 放射治疗 

分 类 号：R318.6[医药卫生—生物医学工程] TH774[医药卫生—基础医学]