Effect of Late‐Stage Meniere's Disease and Vestibular Functional Impairment on Hippocampal Atrophy

Objective We investigated correlations among clinical features, degree of inner ear endolymphatic hydrops (EH), and hippocampal volume (HV) in different stages of Meniere's disease (MD). Methods From February 2021 to April 2022, clinical data were collected from 99 patients (39 males, 60 females, mean age: 50.4 ± 10.0 [range: 26–69] years) with unilateral MD admitted to the Department of Vertigo Disease of Shandong ENT Hospital. The left and right ears were affected in 64 and 35 patients, respectively. There were 50 and 49 cases in early (Stages 1, 2) and late stages (Stages 3, 4), respectively. Fifty healthy participants were included as controls. Audiovestibular function test results, EH grading using gadolinium‐enhanced magnetic resonance imaging (MRI), and HV determined on MRI were analyzed for patients at different stages of MD. Results Between‐group comparisons of early and late MD revealed significant differences in the disease course, vestibular function (VF), degree of EH, and HV. There were no significant between‐group differences based on age, sex, affected side, subjective degree of dizziness, hospital anxiety, or depression. Mean HV in patients with early‐stage MD was correlated with the canal paresis value of the caloric test and pure tone hearing threshold, HV in late‐stage patients was correlated with vestibular EH. Conclusion Patients with late‐stage MD exhibited severe auditory and VF impairments, increased EH, and atrophy of the HV. More advanced disease was associated with greater vestibular damage and degree of EH. Level of Evidence 3 Laryngoscope, 134:410–418, 2024 This cross‐sectional study investigated the correlations among clinical features, degree of inner ear hydrops, and hippocampal volume in patients with different stages of Meniere's disease (MD) at a vertigo center. We found that the left and right hippocampal volumes of patients with MD were smaller than those of the control group, suggesting that the reduction in hippocampal volume was related to MD. Patients with late‐stage MD exhibited severe impairment of auditory and vestibular functions, increased endolymphatic hydrops, and atrophy of the hippocampal volume. More advanced disease was associated with greater vestibular damage and degree of endolymphatic hydrops.