Detection and Grading of Endolymphatic Hydrops in Meniere Disease Using MR Imaging

BACKGROUND AND PURPOSE: Endo lymphatic hydrops has been recognized as the underlying pathophysiology of Meniere disease. We used 3T MR imaging to detect and grade endolymphatic hydrops in patients with Meniere disease and to correlate MR imaging findings with the clinical severity. MATERIALS AND METHODS: MR images of the inner ear acquired by a 3D inversion recovery sequence 4 hours after intravenous contrast administration were retrospectively analyzed by 2 neuroradiologists blinded to the clinical presentation. Endo lymphatic hydrops was classified as none, grade I, or grade II. Interobserver agreement was analyzed, and the presence of endolymphatic hydrops was correlated with the clinical diagnosis and the clinical Meniere disease score. RESULTS: Of 53 patients, we identified endolymphatic hydrops in 90% on the clinically affected and in 22% on the clinically silent side. Interobserver agreement on detection and grading of endolymphatic hydrops was 0.97 for cochlear and 0.94 for vestibular hydrops. The average MR imaging grade of endolymphatic hydrops was 1.27 +/- 0.66 for 55 clinically affected and 0.65 +/- 0.58 for 10 clinically normal ears. The correlation between the presence of endolymphatic hydrops and Meniere disease was 0.67. Endolymphatic hydrops was detected in 73% of ears with the clinical diagnosis of possible, 100% of probable, and 95% of definite Meniere disease. CONCLUSIONS: MR imaging supports endolymphatic hydrops as a pathophysiologic hallmark of Meniere disease. High interobserver agreement on the detection and grading of endolymphatic hydrops and the correlation of MR imaging findings with the clinical score recommend MR imaging as a reliable in vivo technique in patients with Meniere disease. The significance of MR imaging detection of endolymphatic hydrops in an additional 22% of asymptomatic ears requires further study.