Outcomes of Stapedotomy in Patients With Concomitant Otosclerosis and Superior Semicircular Canal Dehiscence: Should a Radiographic Third-Window Be a Contraindication to Stapes Surgery?

OBJECTIVE

Review surgical outcomes of stapedotomy in patients with concomitant otosclerosis and superior semicircular canal dehiscence.

STUDY

DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS: Patients with otosclerosis and radiographic superior semicircular canal dehiscence undergoing stapedotomy between 2008 and 2020.

INTERVENTION: Stapedotomy.

MAIN OUTCOME MEASURES: Pre- and postoperative hearing and unmasking of third-window symptoms. Hearing was measured by air conduction (AC) and bone conduction (BC) pure-tone averages (PTA), air-bone gap (ABG), and word recognition scores (WRS). Third-window symptoms included hyperacusis, autophony, sound- or pressure-induced vertigo, imbalance, or oscillopsia.

RESULTS

Twenty patients with otosclerosis and radiographic superior semicircular canal dehiscence underwent stapedotomy, 13 primary and 7 revision. Mean AC PTA was 49.3 dB preoperatively and 35.6 dB postoperatively (p = 0.0077), while the ABG improved on average from 23.9 to 9.68 dB (p < 0.0001). The ABG improved to ≤10 dB in 12/20 patients (60%), and ≤20 dB in 18/20 patients (90%). There was no significant difference in BC PTA or WRS postoperatively. Two patients (10%) experienced potential transient unmasking of third-window symptoms-hyperacusis and prolonged imbalance-which both resolved. There were no other complications. There was no significant difference in audiologic outcomes or unmasking of third window symptoms between primary or revision cases.

CONCLUSIONS

Persistent conductive hearing loss is common following stapedotomy for otosclerosis in patients with concomitant superior semicircular canal dehiscence. However, a majority of patients can achieve excellent hearing outcomes, while unmasking of third window symptoms appears to be rare. Radiographic superior semicircular canal dehiscence may not be an absolute contraindication to stapes surgery for otosclerosis.