面神经超兴奋性的临床和实验研究

目的：研究面神经麻痹、面神经超兴奋性的临床表现、意义及产生机制。方法：应用神经兴奋性测试仪测试100名正常人面神经兴奋性阈值的范围，并与190例面神经麻痹患者的兴奋性测试结果对照。制作豚鼠面神经麻痹试验模型，应用诱发肌电图测试肌动电位，透射电镜观测神经纤维髓鞘的改变。比较超兴奋性组及非超兴奋性组的临床治愈天数。结果：正常人双侧面神经兴奋性阈值的范围为1.72～-1.57?mA，190例面神经麻痹中29例面神经呈超兴奋性。超兴奋性组临床治愈平均需（3.4±6.0）d，非超兴奋性组临床治愈平均需（42.6±11.2）d，两组差异有统计学意义（P＜0.01）。23只豚鼠中，8只面神经压迫后阈值比压迫前下降，呈超兴奋性，电镜下可见神经纤维髓鞘板层轻度开离。结论：面神经麻痹呈面神经超兴奋性者预后良好。呈现超兴奋性与髓鞘板层开离及与使神经兴奋性增强的离子浓度增加有关。

Clinical and experimental study on the over-excitatory of facial nerve in intratemporal facial paralysis

Objective: To study the manifestation, significance and mechanisms of facial nerve over excitatory in facial paralysis. Methods： The normal threshold of the excitatory of facial nerve was tested in 100 normal persons by nerve excitatory testing machine. The excitatory of 190 patients suffering from facial paralysis was also tested. The experimental model of facial paralysis was made in guinea pigs. Electromyograph was tested and the changes of myelin sheath of nerve fibers were observed by transmission electron microscope. The cure duration of the over and none over excitatory group was compared by t test. Results: The normal threshold of excitatory of facial nerve was 1.72～-1.57 mA in normal person. Of the 190 patients suffering from facial paralysis, 29 showed over excitatory. It took (23.4±6.0)days for the over excitatory group to be clinically cured, while it took (42.6±11.2)days for the none over excitatory group(P＜0.01). The threshold of 8 guinea pigs decreased after compression in 23 guinea pigs showing over excitatory. Slight separation of myelin sheath layer of nerve fibers was observed by electron microscopy. Conclusion: The prognosis of facial paralysis with over excitatory is good. Over excitatory and separation of myelin sheath make the amount of ions that increase the excitatory of nerve.