桥小脑角肿瘤术中电生理监测对面、听神经功能保护的价值

Research of facial and auditory nerve preservation in cerebellopontine angle tumor intraop- erative electrophysiological monitoring

目的：探讨面部肌肉肌电图（EMG）和脑干听觉诱发电位（BAEP）在桥小脑角（CPA）肿瘤切除手术中对面、听神经功能保护的价值。方法：使用美国Nicolet公司生产的Viking-Ⅳ肌电图／诱发电位仪术中监测系统，对收治的20例CPA患者进行了术中监测面部肌肉自发与诱发EMG和BA-EP，并术后对患者进行面、听神经功能评估。结果：本组术中面神经解剖学保留20例（100％），术后面神经功能Ⅰ-Ⅱ级13例（65％），Ⅲ、Ⅳ级7例（35％）；术中BAEP患侧变化不大，健侧Ⅰ-Ⅴ、Ⅲ-Ⅴ波的峰间潜伏期变化最明显，术后听力均无明显改善。结论：在CPA手术中，自发与诱发EMG监测可以提示面神经的位置和走行，显著提高面神经的功能保护率。采用BAEP实时监测，健侧Ⅰ-Ⅴ、Ⅲ-Ⅴ波的峰间潜伏期监测指标可及时为术者提供脑干功能的情况，但对听力的保护意义较小。

Objective.. To investigate the electromyogram of facial muscles （EMG） and brainstem auditory evoked potential （BAEP） of the auditory nerve,and facial nerve andction preservation in eerebel- lopontine angle （CPA） tumor resection surgery. Methods：Viking-Ⅳ / EMG evoked potential instrument made in USA Nicolet comany was used to monitor the facial muscle spontaneous and evoked EMG and BAEP in surgery and essess the facial, acoustic nerve function from 20 patients wirn CPA. Results： The intraoperative facial nerve anatomic preservation was in all the 20 cases （100 % ）, 13 cases had function of facial nerves （65%） ,belonged to class Ⅰ -Ⅱ,and 7 cases （35%） belonged to class Ⅲ ,Ⅳ. After the operation,BAEP had little change on the contralateral side, Ⅰ-Ⅴ ,The latency of Ⅲ-Ⅳ wave peaks had most obvious changes In operation. There was no obvious improvement in hearing after operation. Conclusion.. In CPA surgery, spontaneous and evoked EMG monitoring can prompt facial nerve position and walking and can significantly improve the rate of facial nerve protective function. The real-time monitoring of BA- EP,The latency of eontralateral Ⅰ-Ⅴ , Ⅲ-Ⅴ wave peak monitoring indicators can provide timely brain- stem function for patients, but it is nor significant for small hearing protection.