OBJECTIVE Visulization of endolymphatic hydrops has been reported using magnetic resonance imaging (MRI) in patients with Meniere's disease. However, the relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests have not been sufficiently investigated, such as pure tone audiometry (PTA), electrocochleography (EcoG), and vestibular evoked myogenic potential (VEMP). METHODS Here we attempted to visualize endolymphatic hydrops in patients with Meniere's disease using 3Tesla (3T)-MRI following intratympanic gadolinium-diethylene-triamnie petaaetic acidbis (Gd-DTPA) injection and correlated the presence of hydrops with auditory testing. Following intratympanic Gd-DTPA contrast injections in 26 patients diagnosed as having definite Meniere's disease, 3D-fluid-attenuated inversion recovery (3D-FLAIR) sequence imagings were performed. The PTA, EcoG, and VEMP testing was done bilaterally. Patients had typical results of auditory testing for Meniere's disease. RESULTS The 3D-FLAIR MRI clearly demonstrated endolymphatic hydrops with signal voids in the cochlea (81%) and saccule (69%) in the definite Meniere's disease group. Auditory tests verified that the visualized cochlear hydrops (basal turn) was correlated with a high tone hearing threshold in PTA and an abnormal EcoG. Though the absence of VEMP did not correlate with vestibular hydrops on MRI, large vestibular hydrops were detected by imaging. This study demonstrates that endolymphatic hydrops could be visualized by 3D-FLAIR MRI in Meniere's disease patients. CONCLUSIONS Cochlea hydrops and vestibular (saccular) hydrops are readily visualized using these techniques. Hydrops, as visualized on MRI, may be a reliable means to diagnosis Meniere's disease; this is supported by appropriate correlations with auditory vestibular functional testing.