摘要
为了指导脑深部电刺激动物实验中电极植入手术操作和电极植入后刺激参数的选择,针对自主研发的双面硅基微电极阵列,利用有限元建模和仿真方法,对其植入过程中电极与脑组织作用的力学特性和植入后电流刺激下的电学特性进行了探究。仿真基于Comsol Multiphysics有限元建模软件,首先依据微悬梁臂结构对电极进行建模,并将脑组织简化为各向同性的圆柱体以便于问题的分析和求解;然后,依据电极和脑组织的材料特性、仿真要求、模型尺寸进行相应的参数设置和网格划分;最后通过求解器得到仿真结果。力学仿真表明:当电极尖端载荷达到0.14N时微电极达到强度极限,电极植入过程中推力达到0.06N且硬脑膜位移形变为0.8mm时被穿破。电学仿真表明:双面双极刺激下电流强度增大,刺激范围在三维空间方向上同比增大;比较不同的刺激模式,单面刺激的流线弯曲和收敛程度较双面刺激大,导致刺激范围减小,影响了大于改变此电极刺激触点与参考触点的距离。通过动物实验证实了所得结果的有效性和可靠性。
To guide the electrode implantation in the deep-brain stimulation（DBS）animal experiments and the selection of stimulation parameters after implantation,the mechanical properties of interaction between electrode and brain tissues in the process of implantation as well as the electrical properties under current stimulation after implantation were explored by finite element modeling and simulation. Using the finite element modeling software Comsol Multiphysics,the electrode was modeled based on micro cantilever beam structure,and the brain tissue was simplified as isotropic cylinder for ease of analyzing and solving the problem.Then the meshes were generated according to the material properties of electrode and brain tissue,the simulation requirements and the size of model.Finally,the simulation results were obtained by the solver.The mechanical simulation showed that the electrode reached its ultimate strength when the load applied on its tip was 0.14 N,and the dura was punctured when its displacement deformation reached 0.8mm and the thrust value arrived 0.06 Nin the process of implantation.The electrical simulation showed that under double-sided bipolar stimulation,the stimulus range in the three-dimensional directions increased at the same ratio when the stimulus current wasraised. Comparing different stimulation patterns,the current streamline curvature and convergence degrees of single-sided stimulus are larger than that of double-sided stimulus,leading to a decrease in the stimulus range.This impact on the stimulus effect was greater than changing the distance between stimulus contact and reference contact.These results were justified effective and reliable by animal experiments.
作者
龚茹雪
赵宗亚
黄洪恩
王珏
GONG Ruxue ZHAO Zongya HUANG Hong＇en WANG Jue(Key Laboratory of Biomedical Information Engineering of Ministry of Education, Xi＇ an J iaotong University, Xi＇ an 710049, China)
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2017年第1期141-146,共6页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(61271088
61431012)
关键词
微电极阵列芯片
有限元仿真
力学特性
电学特性
microelectrode array chip
finite element simulation
mechanical properties
electrical properties
作者简介
龚茹雪（1993-），女，硕士生；
王珏（通信作者），女，教授，博士生导师。
