Magnetic resonance imaging of endolymphatic hydrops: a comparison of methods with and without gadolinium-based...

In the evaluation of endolymphatic hydrops (EH) using magnetic resonance (MR) imaging, hybrid of reversed image of positive endolymph signal and native image of perilymph signal multiplied with heavily T2-weighted MR cisternography (HYDROPS-Mi2) imaging with the intravenous administration of a gadolinium-based contrast agent (IV-GBCA) has been utilized. Recently, MR cisternography (MRC) without GBCA has been proposed as a potential alternative method. However, the feasibility of EH evaluation by MRC without GBCA has not been established. The present study aimed to compare HYDROPS-Mi2 imaging with IV-GBCA to MRC without IV-GBCA for the evaluation of EH. In 40 ears of 20 patients with clinically suspected EH, MRC at pre-IV-GBCA and HYDROPS-Mi2 images from 4 h post-IV-GBCA were analyzed. The saccular height on the MRC (SH-MRC) was measured. The percentage of the volume of the endolymphatic space within the whole lymphatic space of the vestibule on the HYDROPS-Mi2 image (%EL_volume-HYD) was measured. The correlation between the SH-MRC and %EL_volume-HYD was calculated. The receiver operating characteristic (ROC) of the SH-MRC and %EL_volume-HYD for the clinical diagnosis of EH was evaluated. The Spearman's rank correlation coefficient between the SH-MRC and %EL_volume-HYD was 0.102. The areas under the ROC curve were 0.570 for the SH-MRC, and 0.926 for the %EL_volume-HYD. In conclusion, there was no significant correlation between the MRC without IV-GBCA and the HYDOROPS-Mi2 with IV-GBCA in the evaluation of EH.