Complications in Vestibular Schwannoma Resections via the Retro-Sigmoid Approach

Objective: Surgery is one of the treatment options for vestibular schwannomas (VS), and results have improved enormously during the last decades. Nevertheless, surgical sequels and complications need continuous consideration and were the focus of this study.

Methods: Over the past 6 years, 244 tumor resections were performed in 239 patients (104 males, 135 females) under continuous neuro-monitoring via a retro-sigmoid approach. Auditory and facial functions before and after surgery and the intra- and postoperative complications were analyzed.

Results: Ninety (37%) patients had small tumors (T1–T3A; Hannover Classification) and 154 (63%) patients had large tumors (T3B or T4). Some residual hearing (Hannover Classification I–IV) was documented in 186 patients (76%) before and in 58 patients after surgery. Hearing outcome correlated significantly with tumor size (p = 0.013). Facial palsy was present in 9 patients (HB °3–6) before and in 91 patients after surgery (41 HB°3, 30 HB°4, 20 HB°5–°6). Intra-operative complications included air embolism in 28 cases (11%) and sinus injury in 2. Postoperative cerebrospinal fluid leakage occurred in 22 (9%), some local hemorrhage in 14 (6%), while overall surgical revision was indicated in 15 cases (6%). There was one death, after total resection of an extensive tumor, due to stroke.

Conclusion: Tumor size remains an important risk factor with regard to functional outcome. Functional cranial nerve preservation was achieved at 31% for the auditory and 80% for the facial nerve (HB° 1–3) in this series. To prevent a disadvantage course, surgery at late tumor stages may be avoided by adequate timing of treatment to optimize outcome.