Cong Alexander X, Shen Haiou, Cong Wenxiang, Wang Ge
Biomedical Imaging Division, School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, 1880 Pratt Drive, Blacksburg, VA 24061, USA.
Int J Biomed Imaging. 2007;2007:38168. doi: 10.1155/2007/38168.
The diffusion approximation of the Boltzmann transport equation is most commonly used for describing the photon propagation in turbid media. It produces satisfactory results in weakly absorbing and highly scattering media, but the accuracy lessens with the decreasing albedo. In this paper, we presented a method to improve the accuracy of the diffusion model in strongly absorbing media by adjusting the optical parameters. Genetic algorithm-based optimization tool is used to find the optimal optical parameters. The diffusion model behaves more closely to the physical model with the actual optical parameters substituted by the optimized optical parameters. The effectiveness of the proposed technique was demonstrated by the numerical experiments using the Monte Carlo simulation data as measurements.
玻尔兹曼输运方程的扩散近似最常用于描述光子在浑浊介质中的传播。它在弱吸收和高散射介质中能产生令人满意的结果,但随着反照率的降低,精度会降低。在本文中,我们提出了一种通过调整光学参数来提高扩散模型在强吸收介质中精度的方法。基于遗传算法的优化工具用于寻找最佳光学参数。用优化后的光学参数替代实际光学参数后,扩散模型的表现更接近物理模型。通过使用蒙特卡罗模拟数据作为测量值的数值实验,证明了所提技术的有效性。