Neurochirurgie, Université de Genève Centre Médical Universitaire, Geneva, Switzerland.
Hôpitaux Universitaires de Genève, Geneva, Switzerland.
J Neurol Surg A Cent Eur Neurosurg. 2021 Jul;82(4):317-324. doi: 10.1055/s-0040-1719026. Epub 2021 Jan 21.
The objective of this study was to determine the performance of the standard alarm criterion of motor evoked potentials (MEPs) of the facial nerve in surgeries performed for resections of vestibular schwannomas or of other lesions of the cerebellopontine angle.
This retrospective study included 33 patients (16 with vestibular schwannomas and 17 with other lesions) who underwent the resection surgery with transcranial MEPs of the facial nerve. A reproducible 50% decrease in MEP amplitude, resistant to a 10% increase in stimulation intensity, was applied as the alarm criterion during surgery. Facial muscular function was clinically evaluated with the House-Brackmann score (HBS), pre- and postsurgery at 3 months.
In the patient group with vestibular schwannoma, postoperatively, the highest sensitivity and negative predictive values were found for a 30% decrease in MEP amplitude, that is, a criterion stricter than the 50% decrease in MEP amplitude criterion, prone to trigger more warnings, used intraoperatively. With this new criterion, the sensitivity would be 88.9% and the negative predictive value would be 85.7%. In the patient group with other lesions of the cerebellopontine angle, the highest sensitivity and negative predictive values were found equally for 50, 60, or 70% decrease in MEP amplitude. With these criteria, the sensitivities and the negative predictive values would be 100.0%.
Different alarm criteria were found for surgeries for vestibular schwannomas and for other lesions of the cerebellopontine angle. The study consolidates the stricter alarm criterion, that is, a criterion prone to trigger early warnings, as found previously by others for vestibular schwannoma surgeries (30% decrease in MEP amplitude).
本研究旨在确定面神经运动诱发电位（MEP）标准报警标准在桥小脑角区前庭神经鞘瘤或其他病变切除术中的性能。
本回顾性研究纳入 33 例（16 例为前庭神经鞘瘤，17 例为其他病变）接受经颅面神经 MEP 切除手术的患者。术中应用可重复的 MEP 幅度降低 50%，且刺激强度增加 10%仍无法恢复作为报警标准。术前及术后 3 个月采用 House-Brackmann 评分（HBS）对患者的面神经功能进行临床评估。
在桥小脑角区前庭神经鞘瘤患者中，MEP 幅度降低 30%时具有最高的灵敏度和阴性预测值，即比术中使用的 MEP 幅度降低 50%的标准更严格，更易触发警报。使用新的标准，灵敏度为 88.9%，阴性预测值为 85.7%。在桥小脑角区其他病变患者中，MEP 幅度降低 50%、60%和 70%时具有相同的最高灵敏度和阴性预测值。使用这些标准，灵敏度和阴性预测值均为 100.0%。
桥小脑角区前庭神经鞘瘤和其他病变切除术中发现不同的报警标准。该研究与之前的研究一致，确定了更严格的报警标准，即更易触发早期预警的标准（MEP 幅度降低 30%），这对前庭神经鞘瘤手术有益。
