BACKGROUND: The aim of this study was to analyze complications of vestibular 
schwannoma (VS) microsurgery.
MATERIAL AND METHODS: A retrospective study was performed in 333 patients with 
unilateral vestibular schwannoma indicated for surgical treatment between 
January 1997 and December 2012. Postoperative complications were assessed 
immediately after VS surgery as well as during outpatient followup.
RESULTS: In all 333 patients microsurgical vestibular schwannoma (Koos grade 1: 
12, grade 2: 34, grade 3: 62, and grade 4: 225) removal was performed. The main 
neurological complication was facial nerve dysfunction. The intermediate and 
poor function (HB III-VI) was observed in 124 cases (45%) immediately after 
surgery and in 104 cases (33%) on the last followup. We encountered disordered 
vestibular compensation in 13%, permanent trigeminal nerve dysfunction in 1%, 
and transient lower cranial nerves (IX-XI) deficit in 6%. Nonneurological 
complications included CSF leakage in 63% (lateral/medial variant: 99/1%), 
headache in 9%, and intracerebral hemorrhage in 5%. We did not encounter any 
case of meningitis.
CONCLUSIONS: Our study demonstrates that despite the benefits of advanced 
high-tech equipment, refined microsurgical instruments, and highly developed 
neuroimaging technologies, there are still various and significant complications 
associated with vestibular schwannomas microsurgery.