Department of Neurological Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
J Neurosurg. 2013 Apr;118(4):719-24. doi: 10.3171/2013.1.JNS121153. Epub 2013 Feb 8.
The primary aim of this study was to evaluate the incidence and discuss the pathogenesis of high-frequency hearing loss (HFHL) after microvascular decompression (MVD) for hemifacial spasm (HFS).
Preoperative and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from 94 patients who underwent MVD for HFS were analyzed. Pure tone audiometry at 0.25-2 kHz, 4 kHz, and 8 kHz was calculated for all individuals pre- and postoperatively ipsilateral and contralaterally. Intraoperative neurophysiological data were reviewed independently. An HFHL was defined as a change in pure tone audiometry of more than 10 dB at frequencies of 4 and 8 kHz.
The incidence of HFHL was 50.00% and 25.53% ipsilateral and contralateral to the side of surgery, respectively. The incidence of HFHL adjusted for conductive and nonserviceable hearing loss was 26.6% ipsilaterally. The incidence of HFHL at 4 and 8 kHz on the ipsilateral side was 37.23% and 45.74%, respectively, and it was 10.64% and 25.53%, respectively, on the contralateral side. Maximal change in interpeak latency Waves I-V compared with baseline was the only variable significantly different between groups (p < 0.05). Sex, age, and side did not increase the risk of HFHL. Stepwise logistic regression analysis did not find any changes in intraoperative BAEPs to increase the risk of HFHL.
High-frequency hearing loss occurs in a significant number of patients following MVD surgery for HFS. Drill-induced noise and transient loss of CSF during surgery may impair hearing in the high-frequency ranges on both the ipsilateral and contralateral sides, with the ipsilateral side being more affected. Changes in intraoperative BAEPs during MVD for HFS were not useful in predicting HFHL. Follow-up studies and repeat audiological examinations may be helpful in evaluating the time course and prognosis of HFHL. Prospective studies focusing on decreasing intraoperative noise exposure, as well as auditory shielding devices, will establish causation and allow the team to intervene appropriately to decrease the risk of HFHL.
本研究的主要目的是评估微血管减压术（MVD）治疗面肌痉挛（HFS）后高频听力损失（HFHL）的发生率，并探讨其发病机制。
分析 94 例行 MVD 治疗 HFS 的患者的术前和术后听力图数据及脑干听觉诱发电位（BAEP）。所有患者均在术前和术后对同侧和对侧进行 0.25-2 kHz、4 kHz 和 8 kHz 的纯音测听。术中神经生理数据由独立人员进行回顾。HFHL 的定义为 4 kHz 和 8 kHz 时纯音测听的变化超过 10 dB。
HFHL 的发生率分别为手术侧同侧和对侧的 50.00%和 25.53%。调整传导性和不可用性听力损失后，同侧 HFHL 的发生率为 26.6%。同侧 4 kHz 和 8 kHz 的 HFHL 发生率分别为 37.23%和 45.74%，对侧分别为 10.64%和 25.53%。与基线相比，波 I-V 峰间潜伏期的最大变化是组间唯一有显著差异的变量（p < 0.05）。性别、年龄和侧别均不能增加 HFHL 的风险。逐步逻辑回归分析未发现术中 BAEP 变化增加 HFHL 的风险。
MVD 手术治疗 HFS 后，相当数量的患者出现高频听力损失。手术过程中钻头引起的噪音和脑脊液的短暂损失可能会导致同侧和对侧高频范围内的听力受损，且同侧更为严重。MVD 治疗 HFS 过程中 BAEP 的变化对于预测 HFHL 没有帮助。随访研究和重复听力检查可能有助于评估 HFHL 的时间过程和预后。关注术中噪声暴露降低以及听觉屏蔽装置的前瞻性研究将确定病因，并使团队能够适当干预以降低 HFHL 的风险。
