视网膜上假体电刺激脉冲参数的优化

发布时间：2018-10-26 20:48

【摘要】：目的目前视网膜上假体的常用刺激波形是双相不对称矩形脉冲,而脉冲参数是影响刺激响应的主要因素之一。本文目的是寻找视网膜上假体的最佳脉冲参数组合。方法视神经节细胞用房室模型模拟,膜特性采用Fohlmeister-Colman-Miller(FCM)模型。双相不对称矩形脉冲的参数包含阴极相幅值,阴极相持续时间,阴极相与阳极相幅值比和相间间隔。胞外理想点电极刺激视神经节细胞的仿真期间,寻找产生动作电位(AP)的最佳脉冲参数组合。刺激有效性采用刺激阈值,阴极相传递电荷量和能量消耗来比较。结果阴极相持续时间为1 ms,阴极相与阳极相幅值比为1和相间间隔为0.1 ms时有最低刺激阈值。阴极相持续时间为0.1 ms,阴极相与阳极相幅值比为1和相间间隔为0.2 ms时获得最低阴极相传递电荷量。最低能量消耗在阴极相持续时间0.9 ms,阴极相与阳极相幅值比10和相间间隔0.6 ms。结论在最低刺激阈值,最低阴极相传递电荷量和最低能量消耗时,双相不对称矩形脉冲参数组合不同。这些为视网膜上假体选择合适的脉冲参数组合提供一个有意义的参考。
[Abstract]:Objective at present, the commonly used stimulus waveform of retinal prosthesis is biphasic asymmetric rectangular pulse, and pulse parameter is one of the main factors that affect the stimulus response. The aim of this paper is to find the best pulse parameter combination for the supraretinal prosthesis. Methods the optic ganglion cells were simulated by atrioventricular model and the membrane characteristics were modeled by Fohlmeister-Colman-Miller (FCM) model. The parameters of the biphase asymmetric rectangular pulse include the amplitude of the cathode phase, the duration of the cathode phase, the amplitude ratio of the cathode phase to the anode phase and the phase spacing. During the simulation of stimulation of optic ganglion cells by extracellular ideal point electrode, the best pulse parameter combination was found to produce action potential (AP). Stimulation effectiveness is compared by stimulation threshold, cathode phase charge transfer and energy consumption. Results when the cathode phase duration is 1 ms, the amplitude ratio of cathode phase to anode phase is 1 and the phase interval is 0. 1 ms, there is a minimum stimulation threshold. When the cathode phase duration is 0. 1 ms, the amplitude ratio of the cathode phase to the anode phase is 1 and the phase interval is 0. 2 ms, the lowest phase transfer charge is obtained. Minimum energy consumption at cathode phase duration 0.9 ms, amplitude ratio of cathode phase to anode phase 10 and phase interval 0.6 ms. Conclusion at the lowest stimulation threshold, the lowest cathode phase transfer charge and the lowest energy consumption, the combination of biphase asymmetric rectangular pulse parameters is different. These provide a meaningful reference for the selection of appropriate pulse parameters for the retinal prosthesis.
【作者单位】：天津医科大学生物医学工程学院;天津大学系统工程研究所;
【基金】：国家自然科学基金资助项目(30870649)
【分类号】：R318.11

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