Speech Perception Performance Growth and Benchmark Score Achievement After Cochlear Implantation for Single-Sided Deafness

Abstract

Objectives: Compare speech perception performance growth and benchmark score achievement among adult cochlear implant (CI) recipients with single-sided deafness (SSD) versus bilateral moderate to profound hearing loss.

Study design: Retrospective matched cohort analysis.

Setting: Tertiary referral center.

Patients: Adults with SSD or bilateral moderate to profound hearing sensorineural hearing loss who underwent cochlear implantation from 2014 to 2019.

Interventions: Cochlear implantation.

Main outcome measures: Time-to-benchmark speech perception score (CNC, AzBio in quiet) and speech performance within first postoperative year.

Results: Thirty-three SSD patients were matched to 66 bilateral hearing loss patients (referent cohort) for duration of deafness and preoperative ipsilateral CNC scores. Although SSD patients were more likely to achieve benchmark CNC scores more quickly compared with matched referents, this difference did not reach statistical significance (HR 1.72; 95% CI 0.78-3.82; p = 0.18). AzBio scores showed similar trends (HR 1.40; 95% CI 0.66-2.98; p = 0.38). At last follow-up, the SSD cohort had lower CNC (median 54% vs. 62%; p = 0.019) and AzBio scores (median 72% vs. 84%; p = 0.029) compared to the referent cohort.

Conclusions: No significant difference in speech perception performance growth (i.e., time-to-benchmark speech perception score) was identified between SSD and bilateral hearing loss CI recipients, although patients with bilateral hearing loss achieved higher scores in the implanted ear within the first year of follow-up.