Department of Neurosurgery, Indonesia National Brain Center Hospital, Special Capital Region of Jakarta, East Jakarta, Indonesia.
Department of Neurosurgery, Koto Memorial Hospital, 2-1 Hiramatsu-cho, Higashiohmi-shi, 527-0134, Shiga, Japan.
Neurosurg Rev. 2024 Oct 15;47(1):798. doi: 10.1007/s10143-024-03017-4.
The removal of vestibular schwannomas carries a risk of facial palsy. This study aims to evaluate the usefulness and technical aspects of intraoperative monitoring (IOM) for the facial nerve. A total of 96 patients who underwent surgery for vestibular schwannoma were retrospectively investigated. The cohort was divided into two groups: those with intraoperative facial nerve monitoring (IOM group) and those without IOM (non-IOM group). Preoperative and postoperative facial nerve functions were assessed using the House-Brackmann (HB) scale immediately after surgery, at discharge, and at the 1-year follow-up. HB grade I and II were classified as satisfactory outcomes, HB grade III and IV as intermediate, and HB grade V and VI as poor. Facial nerve functions were compared between the groups. Additionally, the ratio of satisfactory results was investigated in the IOM group, focusing on whether the root exit zone (REZ) was identified at an early or late stage of surgery. Among the 65 (67%) patients in the IOM group and 31 (32%) patients in the non-IOM group, there were no differences in demographic and tumor characteristics. The extent of resection varied from subtotal to gross total removal, with no statistical differences between the groups. Although facial nerve function was more favorably preserved in the non-IOM group immediately after surgery, this trend reversed at discharge and the 1-year follow-up, showing significant statistical differences. In the IOM group, more patients achieved satisfactory outcomes when the REZ was identified early compared to late during tumor resection. Intraoperative facial nerve monitoring provides more satisfactory outcomes in preserving nerve function in vestibular schwannoma surgery. Early recognition of the REZ may contribute to improved surgical outcomes.
前庭神经鞘瘤切除术存在面瘫风险。本研究旨在评估术中监测（IOM）对面神经的有用性和技术方面。回顾性调查了 96 例因前庭神经鞘瘤而行手术的患者。该队列分为两组：术中面神经监测组（IOM 组）和无 IOM 组（非 IOM 组）。术后即刻、出院时和 1 年随访时使用 House-Brackmann（HB）量表评估术前和术后面神经功能。HB 分级 I 和 II 为满意结果，HB 分级 III 和 IV 为中等，HB 分级 V 和 VI 为差。比较两组面神经功能。此外，还研究了 IOM 组中满意结果的比例，重点关注在手术的早期还是晚期识别神经根出口区（REZ）。在 IOM 组的 65 例（67%）患者和非 IOM 组的 31 例（32%）患者中，人口统计学和肿瘤特征无差异。切除范围从次全切除到大体全切除不等，两组之间无统计学差异。尽管非 IOM 组术后即刻面神经功能保存更有利，但这种趋势在出院和 1 年随访时发生逆转，具有显著的统计学差异。在 IOM 组中，与肿瘤切除晚期相比，早期识别 REZ 可使更多患者获得满意的结果。术中面神经监测在保留前庭神经鞘瘤手术中的神经功能方面提供了更满意的结果。早期识别 REZ 可能有助于改善手术结果。
