听神经瘤术中EMG监测的重要意义

Significance of EMG monitoring in acoustic neuroma operation

目的探讨显微镜下听神经瘤术中的面神经监测的重要意义及刺激阈值的预测价值。方法 45例听神经瘤患者均采取枕下乙状窦后入路术中在面神经监测下显微镜下切除肿瘤,术中分别记录刺激阈值并术后对面神经功能进行评价。结果肿瘤全切除40例(89%),次全切除5例11%)。面神经解剖保留41例(90%),保留未成功4例(10%)。面神经功能状态H-B分级Ⅰ、Ⅱ级30例(67%),Ⅲ、Ⅳ级10例(22%),Ⅴ、Ⅵ级5例(11%)。肿瘤切除后刺激阈值在脑干端﹑粘连段及内听道端分别小于10mA同时前两者与内听道端比值小于1者面神经功能保留好。结论术中面神经监测可显著提高面神经解剖和功能保留率,并可预测面神经功能。

Objective To study the clinical significance of facial nerve monitoring during acoustic ncuroma operation in the microsurgery, and to evaluate the predictive value of electromyographlc recordings for the immediate facial nerve outcome. Methods The suboccipital retrosigmoid transmeatal approach was used in all cases. Intraoperative monitoring was used to protect facial nerve and evaluate its function. Results Total removal was achieved in 40 patients （89%） and subtotal in 5 cases （11%）. The facial nerve was preserved anatomically in 41 cases（90%）, H-B Grade Ⅰ - Ⅱ in 30 cases（67%）, Grade Ⅲ-Ⅳ in 10 cases（22 %）, Grade Ⅴ - Ⅵ in 5 cases（11% ）. Patient with a stimulation threshold at proximal site and proximal post site after proximal site tumor resection at less than or equal to 10 mA presented with a good facial function. Conclusion Intraoperarive monitoring can increase the anatomical and function preservation rate of facial nerve, and predict its function.