3D electron dose calculation using a Voxel based Monte Carlo algorithm (VMC)
3D electron dose calculation using a Voxel based Monte Carlo algorithm (VMC)
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DOI：
10.1118/1.597673
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发表时间：
1996-04-01
期刊：
影响因子：
3.8
通讯作者：
Friedrich, K
中科院分区：
文献类型：
--
作者：
Kawrakow, I;Fippel, M;Friedrich, K
提出了一种计算电子束剂量的新模型。该算法基于计算机断层扫描（CT）图像定义的二维或三维几何形状。用蒙特卡罗技术求解了电子传递方程。然而，与传统的蒙特卡罗模型（EGS4）相比，在基本电子过程的描述中引入了几种近似和简化，以这种方式将计算时间减少了约35倍，而精度却没有显著损失。蒙特卡罗计算机程序不需要任何预先计算的数据。根据CT立方体的分辨率，128(2)x50矩阵所需的随机访问内存约为16 mb。体素蒙特卡罗模型（VMC）与EGS4和“Hogstrom算法”（MDAH）的计算进行了比较测试，使用了几个虚拟的幻影。在所有情况下，EGS4和VMC之间都有很好的重合，特别是在组织不均匀的地方，而MDAH算法产生的剂量低估高达40%。(C) 1996美国医学物理学家协会。
A new model for calculating electron beam dose has been developed. The algorithm is based on a two- or three-dimensional geometry defined by computerized tomography (CT) images. The Monte Carlo technique was used to solve the electron transport equation. However, in contrast to conventional Monte Carlo models (EGS4) several approximations and simplifications in the description of elementary electron processes were introduced reducing in this manner the computational time by a factor of about 35 without significant loss in accuracy. The Monte Carlo computer program does not need any precalculated data. The random access memory required is about 16 Mbytes for a 128(2)x50 matrix, depending on the resolution of the CT cube. The Voxel Monte Carlo model (VMC) was tested in comparison to calculations by EGS4 and the ''Hogstrom algorithm'' (MDAH) using several fictive phantoms. In all cases a good coincidence has been found between EGS4 and VMC, especially near tissue inhomogeneities, whereas the MDAH algorithm has produced dose underestimations of up to 40%. (C) 1996 American Association of Physicists in Medicine.