Clinical Application of Neuroprotection induced by Electrical Stimulation

(1)经角膜电刺激对视网膜神经节细胞（RGCs）的神经保护作用在前期研究中，我们证实了经角膜电刺激（tscneal electrical stimulation, Tc ES）能有效提高腋切大鼠视网膜神经节细胞（RGCs）的存活率。本研究探讨了TcES对皇家外科学院大鼠（RCS）光感受器存活率的影响。产后3周起，连续4次，每周1次。电图（ERG）显示，与对照组相比，治疗组的暗位阈值反应（STR）幅度较大。组织学研究显示，治疗组外核层厚度明显大于对照组。这些数据表明TcES对光感受器的保护是有效的。(2)视神经病变患者TcES的临床研究。在动物实验的基础上，我们研究了TcES在视神经病变患者中的疗效。IRB从大阪大学医学院委员会获得。研究对象为13只前缺血性视神经病变眼、7只外伤性视神经病变眼和8只视神经萎缩眼。术后4眼（31%）AION、2眼（29%）TON和2眼（25%）OA的视力改善等于或大于0.3 log MAR单位。同时观察瞳孔反射阈值电流（TCPR）、中心或外周磷光阈值电流（TCPP）、视敏度（VA）、视界V/4 （AVF）面积。TCCP与TCPR、VA相关，TCPP与AVF相关。tce后VA的改善与TCCP的改善相关。这些数据表明，TCCP可以反映中央视网膜的功能，而TCPP可以反映周围视网膜的功能。TCPR是反映视网膜总功能的客观参数。

(1)Neuroprotection of photoreceptors by trancorneal electrical stimulation in RCS ratsIn the previous study, we confirmed nth effectiveness of Tanscorneal electrical stimulation (Tc ES) was effective to increase the survival rate of retinal ganglion cells (RGCs) in axotomized rat. In this study we examined the Effect of TcES on the survival rate of photoreceptors in royal college of surgeon's rat (RCS rat). TcES was applied once a week for 4 times from 3 week after birth. Electrortinography (ERG) showed significant large amplitude of scotopic threshold response (STR) in the treated group compared with the control group. Histological study showed the thickness of outer nuclear layer was significantly larger in the treated group compared with the control group. These data showed the effectiveness of TcES for the protection of photoreceptors.(2)Clinical study of TcES in patients of optic neuropathy.Based on the animal study, we investigated the effectiveness of TcES in patients with optic neuropathy. IRB was obtained from the committee of Osaka University Medical School. Thirteen eyes with anterior ischemic optic neuropathy, 7 eyes with traumatic optic neuropathy (TON) and 8 eyes with optic atrophy (OA) were enrolled in the study. After TcES, 4 eyes (31%) with AION, 2 eyes (29%) with TON and 2 eyes (25%) of OA showed an improvement of visual acuity equal or greater than 0.3 log MAR unit. We also investigated the threshold current to evoke pupillary reflex (TCPR), the threshold current to evoke central phosphene (TCCP) or peripheral phosphene (TCPP), visual acuity (VA), the area of visual field of Goldmann perimetry V/4 (AVF). The TCCP correlated with TCPR and VA. TCPP correlated with AVF. The improvement of VA after TcES correlated with the improvement of TCCP. These data suggested that the function of the central retina was reflected by TCCP and that of peripheral retina was reflected by TCPP. TCPR is an objective parameter to represent the total retinal function.