Bilateral Cochlear Implantation Versus Bimodal Hearing in Patients With Functional Residual Hearing: A Within-subjects Comparison of Audiologic Performance and Quality of Life

OBJECTIVE: Evaluate performance and quality of life changes after sequential bilateral cochlear implantation in patients with preoperative residual hearing functioning in a bimodal hearing configuration. STUDY DESIGN: Retrospective analysis using within-subjects repeated measures design. SETTING: Tertiary otologic center. PATIENTS: Twenty-two adult patients with bilateral sensorineural hearing loss who used bimodal hearing before second cochlear implant (CI) meeting the following criteria: 1) preoperative residual hearing (≤80 dB HL at 250 Hz) in the ear to be implanted, 2) implantation with current CI technology (2013–2016), 3) consonant-nucleus-consonant (CNC) speech recognition testing in the bimodal condition preoperatively and bilateral CI condition postoperatively. INTERVENTION: Cochlear implantation. MAIN OUTCOME MEASURES: CNC and AzBio sentence scores in quiet and noise (+5 SNR). Subjective measures of communication difficulty and sound quality were also administered. RESULTS: Twenty-two patients (mean 64 yr, 68% men) were included. At an average follow-up of 11.8 months, CNC scores in the bilateral CI condition (mean 63%, standard deviation [SD] = 22) were significantly better than preoperative bimodal scores with repeated measures analysis (mean 55%, SD = 22) (p = 0.03). AzBio scores in quiet were also higher with bilateral CI (mean 76%, SD = 24) compared with bimodal listening (mean 69%, SD = 29) (p = 0.0007). Global abbreviated profile of hearing aid benefit (APHAB) and overall speech, spatial, and qualities of hearing (SSQ) scores exhibited significant improvement following bilateral implantation (p = 0.006 for both analyses). CONCLUSIONS: For patients using a bimodal hearing configuration with substantial residual hearing in the non-CI ear, bilateral cochlear implantation yields improved audiologic performance and better subjective quality of life, irrespective of the ability to preserve acoustic hearing during the second sided implantation.