2026 Proffered Presentations
S075: RETROSIGMOID VERSUS TRANSLABYRINTHINE RESECTION OF VESTIBULAR SCHWANNOMAS: SURGICAL APPROACH AS A DETERMINANT OF OUTCOMES
Ufuk Erginoglu, MD; Umid Sulaimanov, MD; Yerkebulan Serikkanov, MD; Abdullah Keles, MD; Mustafa K Baskaya, MD; University of Wisconsin - Madison
Background: Vestibular schwannomas are benign tumors located in the cerebellopontine angle. Surgical resection is often required when these tumors grow or cause symptoms. The choice between retrosigmoid (RS) and translabyrinthine (TL) approaches remains a subject of ongoing debate, especially regarding outcomes like hearing preservation, extent of resection, and postoperative complications.
Objective: To systematically evaluate and compare the outcomes of retrosigmoid (RS) and translabyrinthine (TL) surgical approaches for vestibular schwannoma resection. The study focuses on key surgical metrics—including extent of resection, facial nerve preservation, and hearing outcomes—as well as radiographic findings, complication rates, and functional recovery. By analyzing these variables across tumor size and grade, the goal is to inform a more precise, patient-tailored approach selection based on preoperative hearing status and tumor characteristics.
Methods: This retrospective cohort study analyzed 283 patients who underwent RS (n = 76) or TL (n = 207) resection between 2006 and 2023, all performed by a single senior neurosurgeon. Key metrics included gross total resection (GTR), facial nerve preservation, hearing outcomes, postoperative complications, MRI findings, and modified Rankin Scale (mRS) scores. Results were stratified by tumor size and Koos grade.
Results: In Koos grade 3–4 tumors, gross total resection was more frequent with TL (84.8% vs. 69.6%). TL was also associated with superior global functional outcomes (mRS 0–2) at discharge (100% vs. 91.1%) and at 1 year (100% vs. 92.9%). Radiographic complications were significantly lower with TL, including postoperative edema (0.8% vs. 30.4%, p < 0.001) and gliosis (0% vs. 5.4%, p = 0.029). One-year facial nerve preservation was comparable between RS and TL (94.7% vs. 93.9%, p = 1.000) among patients with favorable preoperative function. A larger tumor volume was associated with a reduced gross total resection rate in both TL (p = 0.002) and RS (p < 0.001). In TL, increasing volume correlated with longer operative time (p < 0.001) and hospitalization (p < 0.001). In RS, larger volume was further linked to postoperative edema, gliosis, infarction (all p < 0.001), transient swallowing difficulty (p = 0.004), worse mRS at discharge (p = 0.001) and follow-up (p = 0.004), and higher rehabilitation discharge rates (p = 0.026).
Conclusions: Surgical approach selection for vestibular schwannoma should be guided by preoperative hearing status, tumor size, and functional priorities. The TL approach may optimize resection rates and recovery in patients without serviceable hearing. In contrast, the RS approach achieves comparable facial nerve outcomes in patients with preserved function and remains the preferred approach when hearing preservation is feasible. Tumor volume independently influences surgical outcomes and must be a central consideration in operative planning.