Complications and Management of Large Intracranial Vestibular Schwannomas Via the Retrosigmoid Approach

Objective To investigate the common complications from the microsurgical treatment of large intracranial vestibular schwannoma (VS) via suboccipital retrosigmoid approach and to propose strategies for minimizing such complications. Methods We selected all patients with large unilateral VS from the collected database (1999–2013) who underwent microsurgical resection as their initial treatment for histopathologically confirmed VS. Tumors larger than 30 × 20 mm were defined as large. Results A total of 1167 patients with VS were included. Gross total tumor resection was achieved in 1006 patients (86.2%). The mortality rate is 0.77%. The facial nerve was preserved anatomically in 1083 cases (92.8%), and the functional valuation of the facial nerve according to postoperative House-Brackmann scale showed 423 patients (36.2%) in grades I-II, 534 cases (45.8%) in grade III, and 210 patients (18.0%) in grade IV-VI. The main short-term postoperative complication included new hearing loss (American Institute of Otolaryngology-Head and Neck Surgery grade D) in 634 cases (54.3%), disequilibrium in 250 cases (21.4%), labial herpes in 127 cases (10.9%), meningitis in 115 (9.85%) and lower cranial nerve deficit in 77 cases (6.59%). Follow-up data were available for 978 of the 1167 patients (83.8%). Long-term complications include hearing loss (American Institute of Otolaryngology-Head and Neck Surgery grade D) (75.8%), permanent facial paralysis (11.9%), facial numbness (10.9%), tinnitus (2.96%), chronic headache (2.25%), and taste disturbance (1.43%). Conclusions The key factors for reducing surgical complications include careful assessment of the functions of acoustic and facial nerves as well as a thorough understanding of anatomy via the retrosigmoid approach before operation, skillful microsurgical technique, and monitoring of multiple cranial nerves during resection.