Universidad Nacional del Centro, Department of Physics, Pinto 399, Tandil, Buenos Aires 7000 Argentina.
J Biomed Opt. 2010 May-Jun;15(3):035002. doi: 10.1117/1.3442750.
The study of light propagation in diffusive media requires solving the radiative transfer equation, or eventually, the diffusion approximation. Except for some cases involving simple geometries, the problem with immersed inclusions has not been solved. Also, Monte Carlo (MC) calculations have become a gold standard for simulating photon migration in turbid media, although they have the drawback large processing times. The purpose of this work is two-fold: first, we introduce a new processing criterion to retrieve information about the location and shape of absorbing inclusions based on normalization to the background intensity, when no inhomogeneities are present. Second, we demonstrate the feasibility of including inhomogeneities in MC simulations implemented in graphics processing units, achieving large acceleration factors ( approximately 10(3)), thus providing an important tool for iteratively solving the forward problem to retrieve the optical properties of the inclusion. Results using a cw source are compared with MC outcomes showing very good agreement.
在扩散介质中研究光传播需要求解辐射传递方程，或者最终求解扩散近似方程。除了一些涉及简单几何形状的情况外，浸入式夹杂问题尚未得到解决。此外，蒙特卡罗（MC）计算已成为模拟混浊介质中光子迁移的黄金标准，尽管它们存在处理时间长的缺点。这项工作有两个目的：首先，我们引入了一种新的处理标准，基于对背景强度的归一化，在不存在非均匀性的情况下，从吸收性夹杂中检索位置和形状信息。其次，我们证明了在图形处理单元中实现的 MC 模拟中包含非均匀性的可行性，实现了大的加速因子（约 10(3)），从而为迭代求解正问题以检索夹杂的光学性质提供了重要工具。使用连续波源的结果与 MC 结果进行了比较，显示出非常好的一致性。
