Magnetic Resonance Imaging and the endolymphatic hydrops in Menière’s disease

Background. Over the last decades, continuous efforts to improve the understanding of endolymphatic hydrops (EH) have progressively led to the integration of magnetic resonance imaging (MRI) into the diagnostic work-up of inner ear disorders. In recent years, imaging has gained increasing relevance in patients affected by Menière’s disease (MD), as MRI enables in vivo visualization of fluid compartment alterations. Nevertheless, several critical issues remain unresolved, including technical limitations of MRI protocols, inter-observer variability in EH assessment, heterogeneity of hydrops distribution, and the lack of a clear prognostic or etiopathogenetic interpretation of imaging findings. Methods. A systematic review of the literature was performed using PubMed, EMBASE, Web of Science, and Scopus. Eligible studies were English-language articles investigating the use of MRI for the assessment of EH in the inner ear. Study selection and data extraction were conducted according to PRISMA guidelines. Results. A total of 455 articles were identified, with the earliest publication dating back to 1992. The present review focuses on the most recent evidence, including studies published from January 1st, 202, reflecting advances in imaging techniques and clinical applications. Overall, the included studies consistently reported a high capability of MRI to identify EH and related inner ear abnormalities. Conclusions. Recent literature provides a confirmation of the clinical utility of MRI in MD. Key emerging topics include the evaluation of blood–labyrinth barrier (BLB) dysfunction, the extent and grading of EH, and their correlations with clinical symptoms, audiological test outcomes, as well as disease stage and progression. MRI appears to represent a valuable adjunctive tool in the clinical assessment of MD.