Magnetic resonance imaging of endolymphatic hydrops in patients with unilateral Meniere’s disease: volume ratio and distribution rate of the endolymphatic space

Background Endolymphatic hydrops (ELH), which is a pathological feature of Meniere's disease (MD), is characterized by an extended endolymphatic space (ELS). Aims/objectives We aimed to perform a quantitative volumetric analysis of inner-ear ELH in patients with unilateral MD (uMD). Material and methods This study included 97 patients with definite uMD and 49 control subjects (CS). The ELS/total fluid space (TFS) volume ratio (%) and the distribution rate of the inner-ear components in the ELS (%) were measured using 3D magnetic resonance imaging and compared between patients with uMD and CS. Results Compared to CS, patients with uMD had significantly higher mean ELS/TFS volume ratios for inner-ear components. The mean distribution rate of the inner-ear components in the ELS was not significantly different between the two groups. Conclusions and significance In patients with uMD, ELH was noted to be spread throughout the entire inner ear and the endolymph was evenly distributed in the total ELS. These findings should be useful as a standard reference for further research.