In Vivo Visualized Endolymphatic Hydrops and Inner Ear Functions in Patients With Electrocochleographically Confirmed Meniere's Disease

Objective: To study the correlation between the degree of endolymphatic hydrops as detected in vivo by magnetic resonance (MR) imaging and the auditory and vestibular function in patients with definite Meniere's disease. Study Design: Prospective observational study. Setting: Tertiary referral center for balance disorders. Subjects and Methods: In this prospective study, 41 patients who fulfilled the criteria for definite unilateral Meniere's disease according to the American Association of Otolaryngology-Head and Neck Surgery and who showed a summating potential-to-action potential ratio of greater than 0.4 on electrocochleography were included. Intratympanic contrast-enhanced 3 Tesla MR imaging of the inner ear was performed using a 3D Inversion Recovery Turbo Spin Echo sequence. The degree of endolymphatic hydrops was graded on a Likert scale (0-3) in the cochlea and by vestibular endolymph space ratio in the vestibulum. The degree of hydrops was then analyzed with respect to its correlation with audiometric hearing levels, interaural amplitude ratios of vestibular evoked myogenic potentials, degree of horizontal semicircular canal paresis on caloric irrigation, and disease duration. Results: The degree of hearing loss and the disease duration correlated significantly with cochlear hydrops (r = 0.85; r = 0.34). Sacculus dysfunction was significantly correlated with vestibular hydrops (r = -0.47). There was no significant correlation between horizontal semicircular canal paresis and vestibular hydrops. Conclusion: In patients with clinically and electrocochleographically confirmed definite Meniere's disease, the degree of MR morphological hydrops severity correlates significantly with impairment of hearing function and sacculus function.