Deafness Progressing to Cochlear Implant Eligibility Is Eight Times More Likely in the Hypoplastic Than the Degenerative Endotype of Menière's Disease.

Abstract

Objective: To investigate whether one of the two recently described MD endotypes-defined by either endolymphatic sac degeneration (MD-dg patients) or hypoplasia (MD-hp patients)-is associated with an increased likelihood of undergoing CI.

Study design: Retrospective multicenter cross-sectional study.

Setting: Five tertiary referral centers.

Patients: CI cohort: 115 adult MD patients with a history of uni- or bilateral CI. Non-CI cohort: 72 MD patients with no CI history. All included patients matched current diagnostic criteria for definite MD.

Intervention: Cochlear implantation.

Main outcome measures: Endotype distribution (MD-dg versus MD-hp) between the CI cohort and the non-CI cohort. The endotype was determined using high-resolution CT data based on the angular trajectory of the vestibular aqueduct, following established protocols. Secondary outcomes included disease laterality, age at MD diagnosis, duration of MD, and pre-CI hearing thresholds.

Results: The CI cohort included significantly more MD-hp patients than the non-CI cohort (72% versus 24%, p < 0.0001). The odds ratio of CI for an MD-hp patient relative to an MD-dg patient was 8.4 (95% confidence interval, 4.3-16.1). Pre-CI audiometric data showed no significant differences in hearing thresholds between endotypes, neither in the implanted nor in the non-implanted ear.

Conclusions: The MD-hp endotype, frequently associated with bilateral disease and early-age disease onset, is strongly linked to a higher likelihood of CI. Endotyping of MD patients based on endolymphatic sac pathology can effectively stratify their risk of severe hearing loss, guiding personalized audiological follow-up and clinical decisions regarding potential CI.