Wang Teng, Kleiven Svein, Li Xiaogai
Division of Neuronic Engineering, Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge, Sweden.
Front Bioeng Biotechnol. 2021 Aug 13;9:689020. doi: 10.3389/fbioe.2021.689020. eCollection 2021.
Treatment of cerebral edema remains a major challenge in clinical practice and new innovative therapies are needed. This study presents a novel approach for mitigating cerebral edema by inducing bulk fluid transport utilizing the brain's electroosmotic property using an anatomically detailed finite element head model incorporating anisotropy in the white matter (WM). Three representative anisotropic conductivity algorithms are employed for the WM and compared with isotropic WM. The key results are (1) the electroosmotic flow (EOF) is driven from the edema region to the subarachnoid space under an applied electric field with its magnitude linearly correlated to the electric field and direction following current flow pathways; (2) the extent of EOF distribution variation correlates highly with the degree of the anisotropic ratio of the WM regions; (3) the directions of the induced EOF in the anisotropic models deviate from its isotropically defined pathways and tend to move along the principal fiber direction. The results suggest WM anisotropy should be incorporated in head models for more reliable EOF evaluations for cerebral edema mitigation and demonstrate the promise of the electroosmosis based approach to be developed as a new therapy for edema treatment as evaluated with enhanced head models incorporating WM anisotropy.
脑水肿的治疗仍然是临床实践中的一项重大挑战，需要新的创新疗法。本研究提出了一种新方法，通过利用大脑的电渗特性诱导大量液体运输来减轻脑水肿，该方法使用了一个包含白质（WM）各向异性的详细解剖有限元头部模型。对WM采用了三种代表性的各向异性传导率算法，并与各向同性WM进行了比较。关键结果如下：（1）在施加电场的情况下，电渗流（EOF）从水肿区域流向蛛网膜下腔，其大小与电场呈线性相关，方向遵循电流路径；（2）EOF分布变化的程度与WM区域的各向异性比率高度相关；（3）各向异性模型中诱导的EOF方向偏离其各向同性定义的路径，并倾向于沿主要纤维方向移动。结果表明，在头部模型中应纳入WM各向异性，以便对减轻脑水肿进行更可靠的EOF评估，并证明基于电渗的方法有望作为一种新的水肿治疗方法得到发展，这是通过纳入WM各向异性的增强头部模型评估得出的结论。
