First-Side and Second-Side Repair of Bilateral Superior Canal Dehiscence.

Abstract

Bilateral superior canal dehiscence (SCD) may warrant surgeries on both sides. With repairs of unilateral SCD as reference, we investigate the comparativeeffectiveness of first-side and second-side repairs, in hopes of establishing knowledge that can guide clinical decision-making pertaining the appropriateness of second-side surgeries. Middle fossa SCD repairs at an institution between 2011 and 2022 were analyzed. Multivariable regression models assessed symptom resolution and audiometric improvement with surgery cohort (unilateral SCD repair vs. first-side repair vs. second-side repair) as the primary predictor. All models controlled for patient age, sex, surgery duration, prior ear surgery, and follow-up. A total of 407 repairs (180 unilateral SCD, 172 first-side, and 55 second-side repairs) were analyzed. The rates of overall symptom improvement for auditory and vestibular symptoms were as follows: 81% and 67% for unilateral SCD repairs; 73% and 54% for first-side repairs; and 43% and 51% for second-side repairs, respectively. Compared with first-side repairs, which resolved auditory symptoms at similar rates (aOR 95% C.I. 0.36-1.07) but resolved vestibular symptoms at significantly lower rates (aOR 95% C.I. 0.35-0.93) compared with unilateral SCD repairs, second-side repairs resolved auditory symptoms at significantly lower rates (aOR 95% C.I. 0.10-0.51) but resolved vestibular symptoms at similar rates (aOR 95% C.I. 0.45-2.01). Careful consideration of perioperative symptomatology may inform the appropriateness of second-side surgeries. If auditory symptoms persisted following first-side surgeries, second-side surgeries are less likely to yield resolution. If vestibular symptoms persisted following first-side repairs, second-side repairs may lead to resolution at similar rates as first-side repairs. 3 Laryngoscope, 134:1882-1888, 2024.