电刺激诱发前庭电位  

Vestibular Potentials Evoked by Electrical Stimulation

作　　者：蒋子栋[1] 张连山[1] 倪道凤[1] 曹克利[1] 王直中[1] 

机构地区：[1]中国医学科学院中国协和医科大学协和医院耳鼻喉科

出　　处：《中国医学科学院学报》1999年第3期203-207,共5页Acta Academiae Medicinae Sinicae

基　　金：高教部博士点基金

摘　　要：目的记录电刺激诱发的前庭电位，排除各种干扰，证明此电位的确来自前庭。方法将刺激电极置于豚鼠圆窗，用０．０５ｍｓ电流（０．２５～１．２ｍＡ）刺激后，经头皮电极可记录到诱发电位波；分别选择性切断前庭神经、蜗神经或面神经，给予白噪声掩蔽观察诱发电位波波形变化。结果电刺激豚鼠圆窗，可远场记录到诱发电位波，标记为Ｖ１、Ｖ２、Ｖ３，潜伏期分别为（０．９７３±０．０８６）、（１．６１８±０．１７６）和（２．４１６±０．２７４）ｍｓ。该电位具有生物电反应特性，有神经兴奋阈值、饱和性、适应性、对神经完整性的依赖性。切断同侧蜗神经及面神经，在强白噪声掩蔽下，诱发电位波潜伏期无明显变化；切断同侧前庭神经和处死动物后诱发电位消失。诱发电位分别排除了蜗神经、面神经兴奋和刺激伪迹的可能，具有前庭源性，反映了单侧耳前庭功能。结论电刺激豚鼠圆窗可记录纯前庭源诱发电位。Objective To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule. Methods The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25￣1.2 mA) were used to evoke VsEPs by means of vertex pinna skin electrodes. Results These potentials were short latencies of (0.973±0.086) ms, (1.618±0.176) ms and (2.416±0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve. Conclusions We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.

关 键 词：电刺激 前庭 诱发电位 豚鼠 

分 类 号：R338.3[医药卫生—人体生理学]