Intelligent segmentation and measurement based on U-HRCT to explore the anatomical characteristics of the inner ear in unilateral Meniere's disease: a retrospective quantitative study.

OBJECTIVES

To investigate inner-ear anatomical features and their association with endolymphatic hydrops (EH) in Meniere's disease (MD) using ultra-high-resolution CT (U-HRCT) with automated segmentation and measurement.

MATERIALS AND

METHODS

We retrospectively analyzed U-HRCT data from 105 unilateral MD patients and 100 normal controls. All patients underwent gadolinium-enhanced MRI for EH grading. The TransUNet network segmented cochlear, vestibular, and semicircular canal structures. Cochlear dimensions were extracted via principal component analysis; vestibular morphology was approximated as an ellipsoid. Anatomical parameters were compared among affected/unaffected MD ears and controls; their correlations with EH severity were assessed. Inner-ear metrics were also compared between MD patients stratified by disease duration (≤ 5 vs. > 5 years).

RESULTS

Compared with controls, both affected and unaffected MD ears showed greater cochlear height and smaller modiolus-lateral semicircular canal angles (all p < 0.05), with no difference between MD ears. Cochlear diameters and vestibular dimensions did not differ among groups. Patients with disease duration > 5 years exhibited larger vestibular volume, length B, and AB/BC planar areas (all p < 0.05). Vestibular EH severity correlated positively with the modiolus-superior semicircular canal angle (r = 0.243, p = 0.031) and negatively with AB-posterior and AB-superior semicircular canal angles (r = -0.251, p = 0.026 for both).

CONCLUSIONS

MD is associated with distinct spatial alterations in the inner ear, which may disrupt endolymphatic dynamics and may contribute to EH development. Long disease duration is linked to selective vestibular expansion, whereas key angular relationships remain stable across time.

CRITICAL RELEVANCE STATEMENT: We identified correlations between vestibular-hydrops severity and specific inner-ear angular metrics, suggesting links between anatomical spatial relationships and Meniere's disease (MD) progression. These structural deviations may underlie the pathophysiological basis of MD, affecting endolymphatic flow dynamics and contributing to endolymphatic hydrops development.

KEY POINTS: Endolymphatic hydrops (EH) is a hallmark of Meniere's disease (MD). We observed cochlear-height and spatial-positioning alterations in inner-ear structures in MD. These findings suggest links between anatomical spatial relationships and MD progression.