Bashar M R, Li Y, Wen P
Department of Mathematics and Computing, Centre for Systems Biology, University of Southern Queensland, Toowoomba, QLD 4350, Australia.
Australas Phys Eng Sci Med. 2010 Mar;33(1):11-21. doi: 10.1007/s13246-010-0009-5. Epub 2010 Mar 24.
In this study, we propose a stochastic method to analyze the effects of inhomogeneous anisotropic tissue conductivity on electroencephalogram (EEG) in forward computation. We apply this method to an inhomogeneous and anisotropic spherical human head model. We apply stochastic finite element method based on Legendre polynomials, Karhunen-Loeve expansion and stochastic Galerkin methods. We apply Volume and Wang's constraints to restrict the anisotropic conductivities for both the white matter (WM) and the skull tissue compartments. The EEGs resulting from deterministic and stochastic FEMs are compared using statistical measurement techniques. Based on these comparisons, we find that EEGs generated by incorporating WM and skull inhomogeneous anisotropic tissue properties individually result in an average of 56.5 and 57.5% relative errors, respectively. Incorporating these tissue properties for both layers together generate 43.5% average relative error. Inhomogeneous scalp tissue causes 27% average relative error and a full inhomogeneous anisotropic model brings in an average of 45.5% relative error. The study results demonstrate that the effects of inhomogeneous anisotropic tissue conductivity are significant on EEG.
在本研究中，我们提出一种随机方法，用于在正向计算中分析非均匀各向异性组织电导率对脑电图（EEG）的影响。我们将此方法应用于一个非均匀各向异性的球形人体头部模型。我们应用基于勒让德多项式、卡尔胡宁 - 洛伊夫展开和随机伽辽金方法的随机有限元法。我们应用体积和王的约束条件来限制白质（WM）和颅骨组织隔室的各向异性电导率。使用统计测量技术比较确定性有限元法和随机有限元法产生的脑电图。基于这些比较，我们发现，单独纳入WM和颅骨非均匀各向异性组织特性所产生的脑电图分别导致平均56.5%和57.5%的相对误差。同时纳入两层的这些组织特性产生43.5%的平均相对误差。非均匀头皮组织导致27%的平均相对误差，而完全非均匀各向异性模型带来平均45.5%的相对误差。研究结果表明，非均匀各向异性组织电导率对脑电图有显著影响。
