Removal of large or giant sporadic vestibular schwannomas via translabyrinthine approach: a report of 115 cases.

BACKGROUND/AIMS: The present study was a retrospective analysis of surgical outcomes of large or giant vestibular schwannomas (VSs) via a translabyrinthine approach (TLA).

METHODS

One hundred and fifteen sporadic large or giant VSs (maximal diameter in the cerebellopontine angle ≥31 mm) were operated via TLA between January 2001 and December 2010. We divided patients into two groups: cystic VS (CVS) and solid VS (SVS) group. The surgical outcomes were recorded and compared.

RESULTS

Total, near total, and subtotal tumor removal rate was 89.6, 7.8, and 2.6%, respectively. The near total removal rate in CVS was higher than that in SVS (16.7 vs. 3.8%). The anatomical facial nerve (FN) integrity was preserved in 101 patients (87.8%). More FNs in CVS were interrupted (22.2%). There were 29.6, 56.5, and 13.9% of patients who had a short-term (1 month) FN function of House-Brackmann grade I or II, III or IV, and V or VI, respectively. The CVS had worse FN function than the SVS group. The mortality rate was 0.9%. Cerebrospinal fluid leakage occurred in 8 patients (7.0%). Four (3.5%) patients had recurrence.

CONCLUSIONS

Cyst formation is a crucial factor for surgical outcome of VS. With near total or subtotal tumor removal, worse functional outcomes in large or giant CVSs should be foreseen.