Facial Nerve Function after Microsurgical Removal of the Vestibular Schwannoma

Czech version

Authors: Z. Fík ^1,2; M. Chovanec ³; E. Zvěřina ¹; J. Kluh ¹; O. Profant ^1,4; J. Kraus ⁵; Sabina Hrubá ^1,6; Z. Čada ¹; K. Procházková ³; J. Plzák ¹; J. Betka ¹
Authors‘ workplace: Klinika otorinolaryngologie a chirurgie hlavy a krku 1. LF UK a FN Motol, Praha ¹; Anatomický ústav, 1. LF UK v Praze ²; Otorinolaryngologická klinika 3. LF UK a FN Královské Vinohrady, Praha ³; Oddělení neurofyziologie sluchu, Ústav experimentální medicíny, Akademie věd České republiky, v. v. i., Praha ⁴; Klinika dětské neurologie 2. LF UK a FN Motol, Praha ⁵; Klinika rehabilitace a tělovýchovného lékařství 2. LF UK a FN Motol, Praha ⁶
Published in: Cesk Slov Neurol N 2017; 80/113(5): 545-551
Category: Original Paper
doi: https://doi.org/10.14735/amcsnn2017545

Overview

Technological development in microsurgery during the 20^th century has led to a significant decline in mortality and morbidity of surgical management of vestibular schwannoma. Postoperative facial nerve function is among the main criteria of success. A retrospective analysis focused on 90 patients undergoing retrosigmoid-transmeatal surgery of vestibular schwannoma during 2010–2012. The aim of the study was to evaluate perioperative factors associated with postoperative facial nerve function. Facial nerve was discontinued in nine cases (10%) and was subsequently reconstructed. The position of the facial nerve to the tumor, morphological changes (e.g. elongation and splaying), cystic component of a tumor and an extent of tumor growth into the fundus of the internal acoustic meatus were among the parameters affecting facial nerve preservation. Definitive excellent to good function (House-Brackmann grade 1–3) was achieved in 96% of patients in the group with preserved facial nerve continuity. There was 67% of patients with good definitive postoperative function in the facial nerve reconstruction group. Stimulation threshold at the end of the surgery brought no significant information about definitive function of the facial nerve but it predicted early postoperative outcome. At present, the facial nerve continuity can be preserved in the vast majority of surgically managed vestibular schwannomas cases. It is crucial to define prognostic factors influencing the facial nerve injury outcome and include them into a decision-making protocol. Equally, it is necessary to define factors leading to unfavorable outcomes of the facial nerve function despite its anatomical preservation.

Key words:
facial nerve – vestibular schwannoma – microsurgery – reconstruction

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.

Chinese summary - 摘要

显微手术切除前庭神经鞘瘤后的面神经功能

20世纪显微外科技术的发展使得前庭神经鞘瘤手术治疗的死亡率和发病率显著降低。术后面神经功能是手术成功的主要标准之一。回顾性分析2010 - 2012年间90例前庭神经鞘瘤的逆行手术患者，本研究的目的是评估与术后面神经功能相关的围手术期因素。其中有9例（10％）面神经中断并在随后被重建。面神经相对肿瘤的位置，肿瘤的形态变化（例如伸长和张开），肿瘤的囊性成分和肿瘤生长到内耳道底部的程度是影响面神经保留的参数。在保持面神经连续性的患者中，96％的患者达到了明确的良好功能（House-Brackmann等级1-3）。面神经重建手术后功能恢复良好者占67%。手术结束时的刺激阈值对面部神经的最终功能没有明显的影响，但它预示着术后早期的结果。目前绝大多数经手术治疗的前庭神经鞘瘤病例，面神经连续性可以保留。确定影响面部神经损伤结果的预后因素，并将其纳入决策协议中是至关重要的。同样，有必要定义导致面神经功能不良结果的因素。

关键词：

面神经 - 前庭神经鞘瘤 - 显微手术 - 重建

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