Early and certain Meniere's disease characterization of predictors of endolymphatic hydrops

Joan Lorente-Piera^1,2Víctor Manuel Suárez Vega^3,4Melissa Blanco Pareja⁵Gloria Liaño⁴Octavio Garaycochea²Pablo D Dominguez³Raquel Manrique-Huarte^2*Nicolas Perez-Fernandez⁵

• ¹University of Navarra, Pamplona, Spain
• ²Departamento de Otorrinolaringología, Clínica Universidad de Navarra., Pamplona, Spain
• ³Department of Radiology, University of Navarra Clinic, Pamplona, Navarre, Spain
• ⁴Departamento de Radiología, Clínica Universidad de Navarra, Madrid, España, Spain
• ⁵Department of Otolaryngology, University Clinic of Navarra, Madrid, Madrid, Spain

Ménière's disease (MD) is a rare disorder of the membranous inner ear characterized by recurrent episodes of fluctuating sensorineural hearing loss, tinnitus, aural fullness, and vertigo. Over time, it leads to irreversible auditory and vestibular deficits, significantly impairing quality of life. MD has a genetic component, with about 10% of cases being familial and linked to mutations in genes like OTOG and MYO7A, while sporadic cases show associations with autoimmune and inflammatory processes. Histopathologically, endolymphatic hydrops (EH) is a hallmark feature, reflecting membranous labyrinth distension. This study aimed to evaluate the relationship between the type of onset, phenotypic variants and periods of time progression and the degree of endolymphatic hydrops (EH) in patients with early-stage MD, utilizing advanced imaging techniques such as 3D-FLAIR and 3D-Real-IR. We have restricted the duration of the disease to very early (<3years) to reduce some degree of variability.The clinical symptom grouping at onset has a significant impact on the severity of hydrops, with a clearer effect observed in the vestibule compared to the cochlea. However, this correlation is not seen in the results of functional auditory and vestibular tests. Regarding phenotypes, they do not correlate with EH, but the delayed MD phenotype shows a correlation with the pure tone audiometry (PTA) results in the affected ear and the cVEMP (cervical vestibular evoked myogenic potential) results. Interestingly, the different time periods analyzed do not correlate with the severity of EH, but with the severity of hearing loss as measured with the PTA. Interestingly there is a correlation between EH severity and PTA in the affected ear.