旋转MLC优化适形放射治疗中的射野适形度  

The Field Shape Optimization in Conformal Radiation Therapy by MLC Rotation

作　　者：王彬冰[1] 唐志全[2] 侯氢[1] 

机构地区：[1]四川大学原子核科学技术研究所辐射物理及技术教育部重点实验室,成都610064 [2]四川大学华西医院放疗科,成都610041

出　　处：《生物医学工程学杂志》2006年第3期483-487,共5页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(10275045);教育部优秀青年教师资助计划资助项目

摘　　要：采用多叶准直器(M LC)适形野放疗是临床中常用的技术,但其叶片的有限宽度造成的锯齿形射野轮廓是影响射野适形度的主要原因之一。通过模拟计算,考察了旋转准直器角度对射野适形度的影响,提出用多个旋转M LC野形成复合野以使靶区得到更均匀照射,从而避免靶区上的冷点和危及器官上的热点。结果表明,复合M LC射野不仅可以消除射野的锯齿形边界,明显提高射野的适形情况,同时复合射野后靶区的受照射面积也更均匀,避免了照射冷点的出现。Conformal radiation therapy using multi-leaf collimator （MLC） is considered as a conventional technology in the hospital nowadays. However the stepped leaf edge caused by the finite width of the leaves could influence the conformality that could be achievable. In this paper, the effect produced by rotating the collimator angle on the conformality was investigated. A method, in which multiple MLC fields of various rotation angles are applied, has been proposed to have the targets be more uniformly irradiated and thus to eliminate the cold spots on the targets and hot spots in normal tissues. By simulation, it has been shown that the multiple MLC field method can eliminate the stepped leaf edges and improve the conformality significantly, moreover, the PTV can receive a more uniform delivery with cold spot eliminated.

关 键 词：适形照射 目标函数 复合射野 适形度 多叶准直器 

分 类 号：R815[医药卫生—放射医学]