Correlation of endolymphatic hydrops with clinical characteristics in patients with unilateral Ménière's disease.

Purpose: The development of delayed magnetic resonance imaging (MRI) of the inner ear after intratympanic gadolinium (Gd) injection has allowed the identification of endolymphatic hydrops (EH). We aimed to investigate the correlations between EH and auditory-vestibular clinical symptoms in patients with unilateral Ménière's disease (MD).

Methods: In this retrospective study, 91 patients with definite MD (DMD) and 20 patients with probable MD (PMD) underwent intratympanic injection Gd-enhanced MRI of the inner ear. Pure tone audiometry (PTA), speech discrimination score (SRS), electrocochleography (ECochG), and caloric tests were performed. Clinical features were analysed and compared between the DMD and PMD groups, and the relationships between EH and auditory-vestibular results were investigated.

Results: Cochlear endolymphatic hydrops (C-EH) and vestibular endolymphatic hydrops (V-EH) were more common and more severe in the DMD group than in the PMD group (P < 0.001). EH in both DMD and PMD patients was inconsistent with the results of auditory-vestibular tests. However, in the DMD group, the PTA average in the affected ear was significantly correlated with the severity of both C-EH (ρ = 0.376, P < 0.001) and V-EH (ρ = 0.404, P < 0.001). In the PMD group, C-EH was positively correlated with the 125 Hz PTA result (ρ = 0.449, P = 0.047). Furthermore, the severities of both C-EH (ρ = 0.210, P = 0.047) and V-EH (ρ = 0.266, P = 0.011) were significantly correlated with the disease course in the DMD group. In the PMD group, the severity of V-EH (ρ = -0.494, P = 0.027) was negatively correlated with the course of MD.

Conclusion: Gd-enhanced MRI of the inner ear is a clinically available and effective auxiliary examination that can provide a direct basis for the diagnosis of DMD and PMD.