探讨脑干听觉诱发电位（BAEPs）V波潜伏期和（或）波幅的变化与面肌痉挛（HFS）显微血管减压术（MVD）后听力损失的应用价值。

选取中日友好医院神经外科自2015年9月至2019年8月行MVD治疗的HFS患者的临床资料，分析MVD始末BAEPs的V波潜伏期和波幅的变化以及手术前后听力状况的改变，听力学评估采用平均纯音听力阈值及言语识别率改变。根据美国耳鼻咽喉头颈外科学会分级方法，将术后患者听力分为听力未明显下降组和听力明显下降组。收集术中全程的BAEPs改变，并将BAEPs的V波术中改变分为：无显著异常，单纯V波潜伏期（LwV）延长>1.5 ms，单纯V波波幅（AwV）下降>50%，LwV延长>1.5 ms且AwV下降>50%，LwV延长>1.5 ms或AwV下降>50%，对5组分类模式下术后听力损伤程度与分组的相关性进行统计分析，并分析4组BAEPs改变对术后听力损伤的预测价值。

本研究纳入的1009例行MVD治疗的HFS患者中，943例患者听力未明显下降，66例患者术后听力异常，术中BAEPs监测波形无显著改变，术后出现听力下降5例（0.6%）；术中仅LwV延长>1.5 ms，术后出现听力下降4例（18.2%）；术中仅AwV降低>50%，术后出现听力下降19例（25.0%）；术中"LwV延长>1.5 ms且AwV降低>50%"，术后出现听力下降38例（64.4%）；术中"LwV延长>1.5 ms或AwV降低>50%"，术后出现听力下降61例（38.8%）。各组的阳性预测值比较，结果显示"LwV延长>1.5 ms且AwV降低>50%"最高；"LwV延长>1.5 ms或AwV下降>50%"组的敏感度最高；"LwV延长>1.5 ms且AwV下降>50%"组的特异度最强。

术中BAEPs监测可为MVD术者提供听力参考。术末V波潜伏期延长1.5 ms且波幅降低50%以上阳性预测值最高。术中根据BAEPs监测结果及时调整手术策略，可有效改善术后听力障碍的发生率。

To investigate the correlation between changes in brainstem auditory evoked potentials (BAEPs) Ⅴ wave latency and (or) amplitude and hearing loss (HL) after hemifacial spasm (HFS) microvascular decompression (MVD).

The clinical data of HFS patients treated with MVD in Neurosurgery Department of China-Japan Friendship Hospital from September 2015 to August 2019 were selected to analyze the changes of V-wave latency and amplitude of BAEPs before and after MVD as well as the changes of hearing status before and after MVD. Audiology was evaluated by mean pure tone hearing threshold and speech recognition rate changes. According to the AAO-HNS grading method, the postoperative patients' hearing was divided into non significant HL group and significant HL group. BAEPs changes in the whole intraoperative process were collected, and V-wave intraoperative changes of BAEPs were divided into: no significant abnormality, simple V wave latency (LwV) prolonged >1.5 ms, simple V wave amplitude (AwV) decreased >50%, prolonged >1.5 ms and AwV decreased >50%, LwV prolonged >1.5 ms or AwV decreased >50%. The correlation between the degree of postoperative hearing injury and grouping under the five group classification mode was statistically analyzed, and the predictive value of BAEPs changes on postoperative HL in the four groups was statistically analyzed.

Among 1009 HFS patients who underwent MVD, 943 patients had no significant HL, 66 patients had abnormal hearing after surgery, the waveforms of BAEPs monitoring had no significant change during surgery, and 5 patients (0.6%) had HL after surgery. Intraoperative LwV was prolonged >1.5 ms, and 4 cases (18.2%) had postoperative HL. Intraoperative AwV decreased by more than 50%, and postoperative HL occurred in 19 cases (25.0%). Intraoperative LwV prolonged >1.5 ms and AwV decreased >50%, and postoperative HL occurred in 38 cases (64.4%). Intraoperative LwV prolonged >1.5 ms or AwV decreased >50%, and postoperative HL occurred in 61 cases (38.8%). In addition, positive predictive value of each group was compared. The results showed that "1.5 ms extension of LwV and over 50% reduction of AwV" was the highest. The group "intraoperativLewV prolonged >1.5 ms and AwV decreased >50%" had the highest sensitivity. The group "1.5 ms extension of LwV and over 50% reduction of AwV" had the most strong specificity

Intraoperative BAEPs monitoring can provide reference for MVD patients. The positive prediction of V-wave latency prolonged by 1.5 ms and wave amplitude decreased by more than 50% at the end of operation was the highest among the four groups. In addition, timely adjustment of surgical strategies according to BAEPs monitoring results during surgery can effectively improve the incidence of postoperative hearing impairment.