面肌痉挛显微神经血管减压术中诱发肌电图监测的意义

目的探讨术中面肌异常诱发肌电图监测对显微神经血管减压术的指导意义。方法40例面肌痉挛患者在面肌异常诱发肌电图监测下行显微神经血管减压术。开颅前将刺激电极刺入患侧眼轮匝肌用以刺激面神经颧支，记录电极刺入患侧El轮匝肌用以记录诱发肌电图，分别在硬脑膜切开前、排放脑脊液、剥离压迫血管、垫入Teflon棉后、硬脑膜缝合完毕后行电刺激及记录诱发肌电图。结果39例于术前记录到潜伏期约10毫秒的异常诱发肌电图波形，手术后38例异常诱发反应消失。术后随访5年2个月至6年4个月，平均5年8个月，手术治愈率94．7％，好转率2．6％，复发率2．6％。结论术中面肌异常诱发肌电图监测可客观地指导和判断责任血管和减压效果，对提高手术治愈率具有较高的实用价值。

Intraoperative monitoring of facial aberrant responses during microvascular decompression for hemifacial spasm

Objective To explore the importance of intraoperative aberrant responses monitoring as a guide for microvascular decompression. Method 40 patients of hemifacial spasm underwent intraoperative monitoring of facial aberrant responses during microvascular decompression. Of 40 patients, 23 were female and 17 were male. The age ranged from 32 to 68 years with a mean of 49.8 years. No muscle relaxants were used except for induction of anesthesia. The aberrant responses recorded from the mentalis muscle during stimulation of the temporal branch of the facial nerve, Result Before open the dura mater, 39 out of 40 cases showed aberrant responses with a latency of about 10 msec after stimulation. These responses disappeared in 38 patients at the end of operation. In 11 patients, the abnormal responses disappeared prior to decompression of the nerve, in 22 patients, these response disappeared after interposition of the Teflon between the vessel and the brain stem. In 6 patients, the response did not disappear after decompression of the nerve, multiple vascular compressions occur in 3 cases, in other 3 cases, the Teflon contacted to the facial nerve. In 6 patients, after decompression, no cerebellar retraction, the abnormal responses were reappearance, and disappeared after afresh exploration. Following time is 5.2-6.3 years, means is 5.7 years. The complete recovery rate was 94.7%, Recurrence rate 2.6%, inefficacy 2.6%. Conclusion This study demonstrates that intraoperative facial aberrant response recordings are useful to identify the compressing vessel that causes the spasm and to ensure that complete decompression of the nerve has been accomplished.