【摘要】 目的使用蒙特卡罗算法分析不同照射角度变化对乳腺癌患者术后电子线放疗计划剂量分布影响。方法使用MCNP5蒙特卡罗粒子输运软件包建立乳腺癌患者术后电子线照射模型,模拟电子线照射过程中350°、355°、5°、10°四个照射角度变化,计算靶区胸壁及敏感器官患侧肺、健侧肺、心脏的剂量分布,分析其剂量学特点。结果选取350°、355°、0°、5°、10°五个角度后,0°对照组胸壁接受剂量最高,355°组、350°组、10°组、5°组接受剂量依次降低;敏感器官的接受剂量在旋转角度模拟后均有升高,患侧肺和心脏靠近射野,接受剂量和变化程度均较大,0°对照组、350°组、355°组、10°组、5°组患侧肺接受剂量依次升高,0°对照组、355°组、350°、10°组、5°组组心脏和健侧肺接受剂量依次升高。结论本文使用蒙特卡罗算法对乳腺癌患者术后电子线放疗进行模拟研究,发现不同照射角度变化会降低靶区接受剂量,升高敏感器官接受剂量。更多还原

【Abstract】 Objective To study the dosimetric effect of the rotational angle change in electron beam irradiation after breast surgery by Monte Carlo method. Methods The MCNP5 Monte Carlo code was used to simulate the female patients’ left breast cancer. The irradiation was set 350°、355°、0°、5°、10° rotational angle change. The dosimetric effect of chest wall,two lungs and heart was measured and analysed. Results After the set of 350°、355°、0°、5°、10° rotational angle change,the dose of chest wall of 0°control group was the highest dose,the dose of 355 ° group,350° group,10° group,5° group in turn reduced. The irradiation dose of sensitive organs was increased in the simulation of rotation angle. Two lungs and heart near the radiation field,their dose and the dose change were large. the dose of 0° control group,350° group,355° group,10° group,5° group of the same lung was in turn increased,the dose of 0° control group,355° group,350°,10° group,5° group of the heart and contralateral lung were in turn increased. Conclusion The electron beam irradiation after breast surgery was explored by Monte Carlo simulation,which indicate irradiation angle change target to lower dose of target organs and the higher dose of sensitive organs.更多还原