Yang FuMing, Zhou QiangYi, Bi YunKe, Kudulaiti Nijiati, Fang ChaoYou, Shan Qiao, Liu YaoHua, Wang ZhiYu, Tan Nu, Lou MeiQing
Department of Neurosurgery, Shanghai General Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
Department of Radiology, Shanghai General Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
World Neurosurg. 2025 Apr 18;198:123991. doi: 10.1016/j.wneu.2025.123991.
Koos grade 4 vestibular schwannomas (KG4VSs) pose significant surgical challenges due to their complex anatomy and proximity to cranial nerves. Despite advances in neurosurgery, preserving facial and cochlear nerve functions remains difficult. This study introduces a novel surgical strategy for KG4VS that aims to minimize mechanical traction and maximize functional outcomes through systematic tumor dissection guided by anatomical landmarks in the cerebellopontine angle region.
We reviewed 105 patients with KG4VS and 206 patients with Koos grade 1-3 vestibular schwannomas (KG1-3VSs) to assess the efficacy of our surgical strategy. Surgical anatomy and techniques were detailed. Statistical analysis was performed to compare the outcomes between the KG4VS and KG1-3VS groups.
The surgical protocol initiates with intratumoral decompression to establish a thin capsule, enabling arachnoid dissection from superficial regions (inferior pole, cerebellopontine, and superior pole) down to the brainstem and internal auditory canal. Critical steps involve internal auditory canal adhesion release and precise brainstem depth assessment. Gross total resection rates differed significantly between KG4VS (74.3%) and KG1-3VS (95.1%) (P < 0.001). KG4VS demonstrated lower hearing preservation (38.5% vs. 83.5%) and facial nerve function rates (87.6% vs. 97.5%) compared to KG1-3VS (P < 0.001). Tumor diameter >3 cm (P < 0.001), intraoperative morphology alterations (P < 0.001), and elevated neurostimulation thresholds (P = 0.043) independently predicted long-term facial dysfunction. Postoperative complications comprised infection (3.2%), cerebrospinal fluid leak (2.6%), hemorrhage (2.5%), cranial palsy (1.9%), diplopia (1.0%), and cerebellar edema (0.6%).
The protocol optimizes surgical efficiency and function outcomes (facial/cochlear) in KG4VS by reducing intraoperative variability and clarifying complex anatomy.
库斯4级前庭神经鞘瘤（KG4VS）因其解剖结构复杂且靠近颅神经，给手术带来了重大挑战。尽管神经外科手术取得了进展，但保留面神经和蜗神经功能仍然困难。本研究介绍了一种针对KG4VS的新型手术策略，旨在通过在桥小脑角区域的解剖标志引导下进行系统的肿瘤切除，将机械牵拉降至最低并使功能预后最大化。
我们回顾了105例KG4VS患者和206例库斯1 - 3级前庭神经鞘瘤（KG1 - 3VS）患者，以评估我们手术策略的疗效。详细阐述了手术解剖结构和技术。进行统计分析以比较KG4VS组和KG1 - 3VS组的结果。
手术方案首先进行瘤内减压以形成薄包膜，从而能够从浅表区域（下极、桥小脑角和上极）向脑干和内耳道进行蛛网膜分离。关键步骤包括松解内耳道粘连和精确评估脑干深度。KG4VS的全切除率（74.3%）与KG1 - 3VS（95.1%）有显著差异（P < 0.001）。与KG1 - 3VS相比，KG4VS的听力保留率（38.5%对83.5%）和面神经功能率（87.6%对97.5%）较低（P < 0.001）。肿瘤直径>3 cm（P < 0.001）、术中形态改变（P < 0.001）和神经刺激阈值升高（P = 0.043）独立预测长期面部功能障碍。术后并发症包括感染（3.2%）、脑脊液漏（2.6%）、出血（2.5%）、颅神经麻痹（1.9%）、复视（1.0%）和小脑水肿（0.6%）。
该方案通过减少术中变异性和明确复杂的解剖结构，优化了KG4VS的手术效率和功能预后（面部/蜗神经）。
