The role of magnetic resonance imaging in the diagnosis of endolymphatic hydrops and Ménière's disease

Abstract

Introduction A dedicated 3 T magnetic resonance imaging (MRI) protocol of the inner ear was introduced to evaluate the presence and extent of endolymphatic hydrops (EH). In this pilot study, we assessed retrospectively the sensitivity and specificity of this MRI protocol in patients diagnosed with definite Meniere's disease (MD) according to the new diagnostic criteria. Material and methods The study was performed on a 3-Tesla MRI machine using a three-dimensional-fluid-attenuated inversion recovery (3D-FLAIR) sequence performed 4 hours after an intravenous (IV) injection of a double dose of gadolinium. EH in the cochlea and/or vestibule was classified as either none, grade I or grade II (cf reported criteria in recent literature). Thirty-five patients diagnosed with definite MD (31 unilateral, 4 bilateral) were included (mean age was 54.9 years). For ethical reasons (potential long-term side effects of gadolinium administration), no control group (healthy volunteers) could be included. Results In unilateral definite MD, the MRI was positive in 93% of symptomatic ears and in 16%, it was also positive in the contralateral “asymptomatic ear”. In all patients with bilateral definite MD, the MRI was positive bilaterally. Preliminary data show early detection possibilities of hydrops in non-definite MD patients: probable MD (2/11 ears), delayed MD (3/5 ears), patients with Meniere-like symptoms (7/38). Discussion–conclusions This study confirms that 3 T 3D-FLAIR MRI of the membranous labyrinth performed 4 hours after IV gadolinium administration can be a very helpful tool for diagnosing definite MD. Further and long-term studies in a larger patient population, in other pathologies and in normal healthy subjects will be required to confirm these findings.