Saccular measurements in routine MRI can predict hydrops in Menière's disease

Abstract

Most patients with suspicion of hydrops do not have access to MRI with 3D reconstruction of the endolymphatic space. Our main objective was to show that measurements of the saccule on a non-enhanced 3D-T2 MRI could show hydrops and help diagnose Menière disease. We conducted a prospective study from 2015 to 2016 to compare consecutive patients consulting for Menière's disease to a control group (patients with unilateral non-hydrops disorders and contralateral healthy ears). They all received full auditory and vestibular testing. They also underwent a 3-Tesla 3D-T2 MRI using CISS sequence (0.4 mm thick slices), which were blindly evaluated by two independent neuroradiologists. The saccular height and width were measured in a coronal plane and Menière's disease patients' symptomatic ears were compared to asymptomatic and control ears. 36 patients with definite Menière's disease and 36 control patients were studied, including 42 symptomatic Menière, 30 asymptomatic Menière and 72 control ears. Saccular measurements were significantly different between symptomatic Menière ears compared to healthy ears (1.59 vs 1.32 mm, p < 0.001 for height; 1.13 vs 0.90 mm, p < 0.001 for width). Symptomatic and asymptomatic Menière ears' measurements were not significantly different (p = 0.307 and p = 0.109). Using ROC curve, we found cut-off values for saccular height 1.51 mm, Se = 63%, Sp = 95% and width 1.05 mm, Se = 41%, Sp = 95%. Routine 3D-T2 MRI, which patients must undergo for differential diagnosis, could help diagnose hydrops with high specificity using saccular measurements.

Keywords: 3D-T2; Hydrops; MRI; Menière’s disease; Saccule.