Object: To present our experience on hearing and facial nerve function preservation in microsurgical
treatment of small vestibular schwannomas (VSs) via the middle cranial fossa approach.
Methods: We performed a retrospective analysis of 83 cases of small VSs that underwent surgery
via middle cranial fossa approach for hearing and facial nerve preservation between
May 2016 and August 2018.
Results: The patients consisted of 38 men and 45 women, aged 20 to 72 years. Total excision
of the tumor was 75/83 cases (90.4%), subtotal resection was 5/83 cases (6.0%), and
nearly total resection was 3/61 (3.6%). Tumor size ranged from 0.3 to 2.1 cm.
Six patients presented with Class A hearing preoperatively. Among these, 4 patients
(66.7%) maintained Class A postoperatively, 1 (16.7%) deteriorated slightly to Class
C, and 1 (16.7%) deteriorated to Class D postoperatively. Twenty patients presented
with Class B hearing preoperatively. Of these, 10 (50%) remained in Class B, 2 (10.0%)
deteriorated to Class C, and 8 (40.0%) deteriorated to Class D. Thirty-four patients
had Class C hearing preoperatively. Of these, 1 (2.9%) improved to Class A, 2 (5.9%)
improved to Class B, 13 (38.2%) remained in Class C, and 18 (52.9%) deteriorated to
Class D postoperatively. Twenty-three patients presented with Class D hearing preoperatively.
All of them remained Class D postoperatively. Overall, 26 patients presented with
useful (Class A or B) hearing preoperatively and 14 (53.8%) remained useful (Class
A or B) hearing after operation. Facial nerve function was House–Brackmann (HB) Grade
I in 78 patients preoperatively. Postoperatively, facial nerve function was HB Grade
I or 2 in 70 (89.7%) patients, Grade III in 3, and Grade IV in 4, Grade V in 1 at
follow-up of no longer than 6 months. One (1.2%) patient developed transient cerebrospinal
fluid leaks, which was cured by conservative treatment.
Conclusion: The middle cranial fossa approach is an effective and relatively safe option for
the resection of small VSs with hearing and facial nerve preservation. Early intervention,
extensive exposure, facial and cochlear nerve monitoring, meticulous manipulation,
and maintenance of clear tumor–neural interface are the guarantees of good efficacy.