基于共轭梯度法的调强算法的实现  

Implementation of Intensity-modulated Radiation Therapy with Conjugate Gradient

作　　者：钱冯元[1] 葛云[1] 郁洋[1] 

机构地区：[1]南京大学,江苏南京210093

出　　处：《中国医学物理学杂志》2008年第6期867-869,共3页Chinese Journal of Medical Physics

基　　金：放疗导航系统的研究;江苏省教育厅产业化项目(JHB06-01)

摘　　要：目的:研究调强放射治疗(IMRT)的具体实现与约束条件的表述。材料与方法:在每个射野方向上,利用真实的笔形束剂量分布数据,并加入机头散射、组织补偿等因素,计算得到单位剂量笔形束在特定位置形成的剂量分布。在优化过程中,以此笔形束剂量分布为依据进行剂量计算。用VisualC++6.0编写基于共轭梯度法的IMRT的算法实现,并考虑多种约束条件。最后求解优化的射野笔形束权重,并加以分析。结果:在TPS软件中集成IMRT功能,并进行模拟病例的优化,获得了高适形度的剂量分布,满足DVH约束。结论:结合特定的约束条件,共轭梯度法能有效的优化射野笔形束权重,并且有较快的计算速度,有广阔的应用前景。Objective： To study the implementation of intensity-modulated radiation therapy and the description of constraints. Materials and methods： According to each Beam＇s Eye View, using the real beamlets dose distribution, integrated with scattering, tissue compensation, etc., the distribution of unit dose beamlet on the specific position can be obtained. During the optimization, total dose distribution can be obtained according to what we get last step. We have implemented the IMRT optimization algorithm based on conjugate gradient and considered several constraints on Visual C＋＋ 6.0 platform. At last, the optimized weights of beamlets were obtained and analyzed. Results： We integrated IMRT in TPS, and then a simulated case was processed. We obtained highly conformal dose distribution which met the required DVH. Conclusion： With specialized constraints, conjugate gradient can efficiently optimize the weights of beamlets in field. This method has considerable high speed and wide application prospect.

关 键 词：调强放疗 共轭梯度法 目标函数 约束条件 

分 类 号：R815[医药卫生—放射医学]