Gadolinium-Enhanced MRI Classification of Sudden Sensorineural Hearing Loss and Its Clinical Correlates

ImportanceSudden sensorineural hearing loss (SSNHL) has heterogeneous etiologies and prognoses. Early-imaging evaluation may help identify patients at higher risk of poor hearing recovery.ObjectiveTo investigate the relationship between labyrinthine gadolinium-enhanced MRI (Gd-MRI) findings and clinical characteristics in patients with SSNHL and to assess the clinical value of MRI-based subtyping for early evaluation and stratified treatment.DesignRetrospective observational study.SettingSingle tertiary referral center.ParticipantsNinety-six patients with unilateral SSNHL treated between January 2014 and May 2020 were included.Exposure or InterventionAll patients underwent gadolinium-enhanced inner ear MRI. According to imaging features, they were categorized into an MRI-negative group, an endolymphatic hydrops (EH) group, and a labyrinthine signal abnormalities (LSA) group.Main Outcome MeasuresClinical symptoms, audiological data, inner ear subunit involvement, and short-term hearing gain were compared among groups. Independent predictors of hearing improvement were analyzed using multivariate linear regression.ResultsAmong 96 patients, 55 were MRI-negative, 20 were EH, and 21 were LSA. The LSA group had the highest rates of vertigo and tinnitus (100% and 95.2%, respectively; P = .001, P = .038) and more extensive inner ear involvement (≥2 subunits, 71.4%; P = .003). Pretreatment hearing thresholds were comparable between groups, but the LSA group had a significantly-poorer pure-tone average after treatment. Multivariate regression identified age and MRI classification as independent predictors of low-frequency hearing gain (P < .05).ConclusionGadolinium-enhanced inner ear MRI effectively stratifies SSNHL by identifying distinct imaging phenotypes correlated with clinical severity and recovery potential. Labyrinthine signal abnormalities, indicating more extensive inner ear involvement, are associated with poorer hearing recovery.RelevanceMRI-based subtyping can facilitate early evaluation and individualized management of SSNHL, supporting its integration into routine diagnostic assessment. These preliminary findings require confirmation through larger prospective studies with long-term follow-up.