Mukumoto Nobutaka, Tsujii Katsutomo, Saito Susumu, Yasunaga Masayoshi, Takegawa Hideki, Yamamoto Tokihiro, Numasaki Hodaka, Teshima Teruki
Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Int J Radiat Oncol Biol Phys. 2009 Oct 1;75(2):571-9. doi: 10.1016/j.ijrobp.2009.02.088.
To develop an infrastructure for the integrated Monte Carlo verification system (MCVS) to verify the accuracy of conventional dose calculations, which often fail to accurately predict dose distributions, mainly due to inhomogeneities in the patient's anatomy, for example, in lung and bone.
The MCVS consists of the graphical user interface (GUI) based on a computational environment for radiotherapy research (CERR) with MATLAB language. The MCVS GUI acts as an interface between the MCVS and a commercial treatment planning system to import the treatment plan, create MC input files, and analyze MC output dose files. The MCVS consists of the EGSnrc MC codes, which include EGSnrc/BEAMnrc to simulate the treatment head and EGSnrc/DOSXYZnrc to calculate the dose distributions in the patient/phantom. In order to improve computation time without approximations, an in-house cluster system was constructed.
The phase-space data of a 6-MV photon beam from a Varian Clinac unit was developed and used to establish several benchmarks under homogeneous conditions. The MC results agreed with the ionization chamber measurements to within 1%. The MCVS GUI could import and display the radiotherapy treatment plan created by the MC method and various treatment planning systems, such as RTOG and DICOM-RT formats. Dose distributions could be analyzed by using dose profiles and dose volume histograms and compared on the same platform. With the cluster system, calculation time was improved in line with the increase in the number of central processing units (CPUs) at a computation efficiency of more than 98%.
Development of the MCVS was successful for performing MC simulations and analyzing dose distributions.
开发一种用于集成蒙特卡罗验证系统（MCVS）的基础设施，以验证传统剂量计算的准确性。传统剂量计算常常无法准确预测剂量分布，主要原因是患者解剖结构中的不均匀性，例如肺部和骨骼中的不均匀性。
MCVS由基于MATLAB语言的放射治疗研究计算环境（CERR）的图形用户界面（GUI）组成。MCVS GUI充当MCVS与商业治疗计划系统之间的接口，用于导入治疗计划、创建MC输入文件以及分析MC输出剂量文件。MCVS由EGSnrc MC代码组成，其中包括用于模拟治疗头的EGSnrc/BEAMnrc和用于计算患者/体模中剂量分布的EGSnrc/DOSXYZnrc。为了在不进行近似的情况下缩短计算时间，构建了一个内部集群系统。
开发了来自Varian Clinac单元的6-MV光子束的相空间数据，并用于在均匀条件下建立多个基准。MC结果与电离室测量结果的误差在1%以内。MCVS GUI可以导入并显示由MC方法以及各种治疗计划系统（如RTOG和DICOM-RT格式）创建的放射治疗计划。可以通过使用剂量曲线和剂量体积直方图在同一平台上分析剂量分布并进行比较。借助集群系统，计算时间随着中央处理器（CPU）数量的增加而缩短，计算效率超过98%。
MCVS的开发成功实现了MC模拟和剂量分布分析。
