A comparison between transport and diffusion calculations using a finite element-spherical harmonics radiation transport method
A comparison between transport and diffusion calculations using a finite element-spherical harmonics radiation transport method
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DOI：
10.1118/1.1500404
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发表时间：
2002-09-01
期刊：
影响因子：
3.8
通讯作者：
Goddard, AJH
中科院分区：
文献类型：
--
作者：
Aydin, ED;de Oliveira, CRE;Goddard, AJH
大多数研究者选择对输运方程的扩散近似作为描述光子在生物组织中迁移的模型。然而，这种近似的适用性是有限的，在某些情况下是无效的。本文介绍了一种二维有限元-球谐函数（FE-P-N）辐射输运方法，用于模拟光在组织中的传播。光的传播首先在一个分层的圆柱体中进行研究，这可以被看作是一个非常简单的近似人的头部。然后，在均匀和非均匀介质中，对于不同的g和mu（s）值，研究了各向异性因子g对光子迁移的影响。空洞状的不均匀性和渠道的影响，其中吸收和散射是非常小的，与周围的介质上的光子的传输进行了研究。运输和扩散计算之间的显着差异显示在所有情况下发生。(C)2002年美国医学物理学家协会。
Most researchers choose the diffusion approximation to the transport equation as the model to describe photon migration in biological tissues. However, the applicability of this approximation is limited and, in certain cases, invalid. In this paper we introduce a two-dimensional, finite element-spherical harmonics (FE-P-N) radiation transport method for the simulation of light propagation in tissue. The propagation of light is investigated first in a layered cylinder, which can be seen as a very simplistic approximation of a human head. Effects of the anisotropy factor g on the photon migration is then examined in homogeneous and heterogeneous media for different values of g and mu(s). The influence of void-like heterogeneities and channels in which absorption and scattering are very small compared with the surrounding medium on the transport of photons is also investigated. Significant differences between transport and diffusion calculations are shown to occur in all cases. (C) 2002 American Association of Physicists in Medicine.