[Investigation of the correlation between the degree of endolymphatic hydrops and inner-ear anatomical variations in patients with Menière's disease based on 5.0T inner-ear hydrography and gadolinium-enhanced imaging].

Objective:To evaluate the anatomical variations of the inner ear in patients with Meniere's disease using magnetic resonance imaging（MRI） and to explore the role of these variations in different types of endolymphatic hydrops. Methods:Twenty-eight patients clinically diagnosed with Meniere's disease underwent 5.0T inner ear MRI with gadolinium contrast. All patients received conventional non-contrast inner ear MRI, internal auditory canal hydrography, and 3D-FLAIR sequences. Four hours after intravenous administration of a double dose of gadolinium contrast agent, enhanced 3D-FLAIR and thin-slice T1-weighted fat-suppressed sequences were performed. The distance between the vertical portion of the posterior semicircular canal and the posterior cranial fossa（MRI-PP distance） was measured bilaterally on inner ear hydrography sequences. Two radiologists, each with 10 years of experience in head and neck imaging, independently interpreted the degree of endolymphatic hydrops on the gadolinium-enhanced inner ear images according to Bernaets' visual grading method. Any discrepancies were resolved through discussion. Vestibular hydrops was scored from 0 to 3, and cochlear hydrops was scored from 0 to 2. A total hydrops score for each side（left/right） was calculated as the sum of the vestibular and cochlear scores. SPSS 26.0 statistical software was used for Pearson correlation analysis between these scores and the MRI-PP values. Furthermore, the presence or absence of cochlear and vestibular hydrops was defined as 1 and 0, respectively, and independent samples t-tests were performed between these dichotomized groups and the MRI-PP values. Results:A total of 56 ears from 28 patients were analyzed. The mean total hydrops score was（1.25±0.89） for the left ears and（0.89±0.74） for the right ears. The mean MRI-PP distance was（2.36±1.09） mm for the left side and（2.74±1.41） mm for the right side. Pearson correlation analysis results: For the left side, correlation between the total hydrops score and the MRI-PP distance was not significant（P=0.662）, while correlations between the cochlear hydrops score and the MRI-PP distance（P=0.003）, and between the vestibular hydrops score and the MRI-PP distance（P<0.001） were statistically significant. For the right side, correlations between the total hydrops score and the MRI-PP distance（P=0.402）, between the cochlear hydrops score and the MRI-PP distance（P=0.716）, and between the vestibular hydrops score and the MRI-PP distance（P=0.541） were not statistically significant. Conclusion:The MRI-PP distance has the potential to serve as an imaging anatomical indicator for assessing the risk of developing Meniere's disease, especially for left-sided involvement. 5.0T MRI can effectively advance the imaging diagnosis of Meniere's disease from traditional qualitative assessment toward quantitative evaluation, providing a new technical platform and imaging basis for uncovering the disease's pathogenesis and guiding individualized precision treatment.