为了提高电极的长期有效性，基于鱼骨状神经电极，采用有限元模拟对电极-脑组织界面的微动进行了动力学分析.将该电极与传统商业电极的力学性能进行对比，验证了鱼骨状设计对降低脑组织微动损伤的有效性，并揭示了电极柄数对脑组织应力应变的影响.基于电极位点分布的合理性和最优化原则，提出了一种新型鱼骨状多柄电极.与原鱼骨电极相比，新型鱼骨电极的应变、应力和变形分别降低了 73.23%、48.78% 和 76.92%.将该新型电极与同位点分布的商业三杆电极进行对比，结果表明，在采集到的电信号相同时，新型电极大幅降低了脑组织应变.预期该电极的寿命可以得到有效延长.
In order to improve the long-term effectiveness of neural electrode, kinetic analysis of the micromotion at the electrode-brain interface was conducted using finite element simulation method. Compared with the traditional commercial electrode, the fish-bone-shaped electrode shows great effectiveness in reducing the micromotion induced injury. Moreover, the influence of the number of electrode shanks on micromotion induced injury of brain tissue was revealed. Based on the rationality and optimization principles of electrode site distribution, a novel multi-shank fish-bone-shaped electrode was developed. The electrode decreases the maximum strain, von Mises stress and total deformation of brain tissue by 73.23%, 48.78% and 76.92% respectively compared with the original one. In addition, the novel electrode performs better than the commercial three-shank electrode with the same size and site distribution when both of the electrodes collect the same electrical signal. The results reveal that the novel electrode reduces the strain in the brain tissue considerably, and is expected to improve the lifetime of electrode effectively.
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