Cochlear Implantation Outcomes in Patients With Autoimmune and Immune-Mediated Inner Ear Disease

Abstract

To compare hearing outcomes in patients with autoimmune inner ear disease (AIED) undergoing cochlear implantation to a group of controls, postlingually deafened by non-immune-mediated causes. Hearing performance in AIED patients who receive unilateral or bilateral cochlear implants is comparable to similarly treated postlingually deafened adults without AIED. Retrospective chart review. Academic neurotologic tertiary referral center. Ten patients with AIED with 12 implanted ears who met the audiological criteria for cochlear implantation were compared with 12 randomly selected controls, postlingually deafened by non-immune-mediated causes. Cochlear implantation using commercially available devices. Preoperative and postoperative hearing thresholds, words, and sentence scores. A note was made regarding the presence or absence of ossification or fibrosis noted within the scala tympani at the time of implant. The mean age was 49.6 ± 14 years in the AIED group and 56.8 ± 17 years in the control group (p = 0.31). The mean duration of deafness was 14 ± 26 months in the AIED group and 6.5 ± 4 months in the control group (p = 0.34). In the AIED group, 42% were men and 58% were women. In the control group, 33% were men and 67% women. Five patients in the AIED group (6 implanted ears) were found to have cochlear fibrosis and variable degrees of ossification. Two patients in that group required drill-out procedures. All patients had full insertion. The mean preoperative pure-tone averages in the AIED and control groups were 102 ± 18 and 90 ± 13 dB, respectively (p = 0.13). In the AIED, the mean short-term (≤12 mo of follow-up) postoperative word and sentence scores were 74.8% ± 15% and 94% ± 6%, respectively. In the control group, the mean short-term postoperative words and sentence scores were 72% ± 12% and 96% ± 4%, respectively. No statistical difference was present in the short-term postimplantation words (p = 0.7) and sentence scores (p = 0.49) between both groups. The mean long-term (after 12 mo of follow-up) postoperative word and sentence scores in the AIED group were 87.2% ± 11% and 96.8% ± 4%, respectively. In the control group, the long-term words and sentence scores were 77.2% ± 14% and 77.2% ± 7%, respectively. No statistical significance was found in the long-term postimplantation words (p = 0.17) and sentence scores (p = 0.7) between both groups. Cochlear implantation is a safe and viable option for hearing rehabilitation in patients deafened by progressive AIED. Hearing outcomes in AIED patients are excellent and support transition to implantation when hearing is lost or long-term steroid therapy becomes undesirable. Cochlear fibrosis or ossification seems to affect nearly 50% of implanted ears (41.6% of patients) in this study and implies that the cochlea is at risk for ossification changes long term. In appropriate candidates, earlier implantation may be indicated before postinflammatory obliterative changes in the cochlea.