Abstract: Objective To explore the application of membranous concept in vestibular schwannoma surgery. Methods A total of 39 patients with vestibular schwannoma who received membranous surgical treatment in The First Affiliated Hospital of Anhui Medical University from May 2020 to June 2021 were enrolled. Through the retrosigmoid approach, the intraoperative electrophysiological monitoring was performed, and the membranous concept was used to separate the brain stem of the tumor and the interface between the tumor and the facial nerve and the cochlear nerve. Facial nerve function was evaluated by the House-Brackmann (H-B) grade and hearing was evaluated by the American Academy of Otolaryngology-Head and Neck Surgery(AAO-HNS) scale at one day, one week and one year after surgery. Results Total resection was performed in 31 cases (79.49%) and nearly total resection in 8 cases (20.51%). Facial nerve anatomical preservation was achieved in all patients, and facial nerve function returned to normal or nearly normal (H-B grade Ⅰ-Ⅱ) 84.62% (33/39), moderate facial paralysis (H-B grade Ⅲ) 10.27% (4/39), moderate and severe facial paralysis (H-B grade Ⅳ) 5.13% (2/39) on the first day after surgery. One week after surgery, 71.79% (28/39) of patients with normal or nearly normal facial nerve function, 15.38% (6/39) of moderate facial paralysis, 10.27% (4/39) of moderate and severe facial paralysis, and 2.56% (1/39) of severe facial paralysis (H-B grade Ⅴ). One year after surgery, 92.31% (36/39) of patients with facial nerve function returned to normal or nearly normal, 5.13% (2/39) of patients with moderate facial paralysis, and 2.56% (1/39) of patients with moderate and severe facial paralysis. Among the 10 patients (25.64%) who retained effective hearing before surgery (AAO-HNS grade ≥ C), there were 4, 3 and 6 cases at one day, one week and one year after surgery, respectively. Those who did not retain effective hearing before surgery did not recover effective hearing after surgery. According to the comparison of tumor volume and nature, the proportion of patients with normal facial nerve function (H-B grade Ⅰ) in the tumor volume ≤ 3 cm group was higher than that in > 3 cm group[12/18 vs. 19.05% (4/21); Fisher's exact probability:P=0.006], the proportion of patients with normal facial nerve function in the solid tumor group was higher than that in cystic group[71.43% (15/21) vs. 1/10; Fisher's exact probability:P=0.010] at one year after surgery. Conclusions The membranous concept in vestibular schwannoma surgery can protect facial nerve function well, and has a positive effect on the protection of cochlear nerve and brain stem.

Key words: Neuroma, acoustic, Facial nerve, Cochlear nerve, Microsurgery

摘要： 目的 探讨膜性理念在听神经瘤显微外科手术中的应用。方法 纳入2020年5月至2021年6月在安徽医科大学第一附属医院采用膜性理念手术治疗的39例听神经瘤患者，采取乙状窦后入路，术中行电生理监测，膜性理念分离肿瘤脑干面以及肿瘤与面神经和蜗神经界面，术后第1天、1周和1年采用House-Brackmann（H-B）分级评估面神经功能，美国耳鼻咽喉头颈外科学会（AAO-HNS）分级评估听力。结果 有31例（79.49%）肿瘤全切除，8例（20.51%）近全切除。所有患者均实现面神经解剖保留，术后第1天面神经功能恢复正常或接近正常（H-B分级Ⅰ~Ⅱ级） 84.62%（33/39）、中度面瘫（Ⅲ级）10.26%（4/39）、中重度面瘫（Ⅳ级） 5.13%（2/39）；术后1周，面神经功能恢复正常或接近正常71.79%（28/39）、中度面瘫15.38%（6/39）、中重度面瘫10.26%（4/39）、重度面瘫（Ⅴ级） 2.56%（1/39）；术后1年，面神经功能恢复正常或接近正常92.31%（36/39）、中度面瘫5.13%（2/39）、中重度面瘫2.56%（1/39）。10例（25.64%）术前保留实用听力（AAO-HNS分级≥ C级）的患者中，术后第1天、1周和1年分别有4、3和6例仍保留实用听力，术前未保留实用听力者术后均未恢复实用听力。根据肿瘤体积和性质分组比较，术后1年肿瘤体积≤ 3 cm组面神经功能正常（H -B分级Ⅰ级）比例高于> 3 cm组［12/18对19.05%（4/21）；Fisher确切概率法： P=0.006］，肿瘤性质呈实性组面神经功能正常比例高于囊性组［71.43%（15/21）对1/10； Fisher确切概率法： P=0.010］。结论 听神经瘤手术中膜性理念可以较好地保护面神经功能，并对蜗神经和脑干的保护具有积极作用。

关键词: 神经瘤,听, 面神经, 耳蜗神经, 显微外科手术