Magnetic resonance imaging study of endolymphatic hydrops based on 3D-FLAIR sequence after single-dose intravenous gadolinium injection

Abstract

Objective: To investigate the visualization of endolymph in patients with otogenic vertigo by intravenous administration of single dose of gadolinium contrast agents and magnetic resonance three-dimensional fluid-attenuated inversion recovery sequence (3D-FLAIR MRI), and further assess the extent of endolymphatic hydrops. Methods: From Beijing Tongren Hospital of Capital Medical University between October 2017 and June 2018, 30 patients (16 males, 14 females) with unilateral otogenic vertigo were involved in this study, with the age of 30 to 68 years, mean age of (53±10) years. Eight hours after intravenous administration of single dose (0.1 mmol/kg, body weight) of gadopentetate (Gd-DTPA), 3D-FLAIR sequence was performed in 30 patients. The location of endolymphatic hydrops was observed and then the degree of hydrops was quantitatively elevated by two radiologists. The consistency test was used to analyze the location and degree of endolymphatic hydrops in the two radiologists and the paired t-test was used to compare the difference between the affected and healthy side of endolymphatic spaces of the patients with otogenic vertigo. Results: In 30 patients, the gadolinium distributed in all parts of the perilymph inside the inner ear, and can accurately outline the boundaries of the peri-and endolymph. Twenty-six patients (26/30, 86.7%) were found to have unilateral endolymphatic hydrops, including 18 mild hydrops, 8 significant hydrops. The two radiologists had a very good agreement on the assessment of endolymphatic hydrops(kappa=0.864, ICC=0.959). In the 3D-FLAIR MR images of 26 patients with endolymphatic hydrops, the saccule (26/26, 100%) had a higher rate of hydrops than the cochlea and utricle(16/26, 61.5%; 14/26, 53.8%), and two radiologists had a very good agreement on the location of endolymphatic hydrops(kappa=0.820). Moreover, there was a significantly statistical difference between the affected and healthy area of the endolymphatic space in this study (P<0.01). Conclusion: The technique of 3D-FLAIR MR imaging through single dose intravenous gadolinium injection is feasible, which can estimate endolymphatic hydrops in patients with otogenic vertigo, and accurately classify the degree of hydrops.