In 106 patients / 212 ears, UHR temporal-bone PCCT enabled reproducible quantification of vestibular aqueduct (VA) morphology, with excellent interobserver agreement for angular trajectory (ATVA), width, length, and posterior semicircular canal–posterior fossa distance (ICC 0.84–0.91). VA morphology differed significantly across Ménière’s disease endotypes, supporting PCCT-derived osseous morphometry as a potential imaging biomarker.
For hypoplastic Ménière’s disease, VA visibility grade achieved AUC 0.860 with 100% sensitivity and 71.8% specificity; for the degenerative endotype, combined VA morphology and midpoint width achieved AUC 0.784, sensitivity 83.9%, and specificity 80.0%. Leave-one-patient-out cross-validation produced only modest AUC decreases, supporting internal robustness.
VA structure was also associated with hearing impairment: ATVA independently predicted pure-tone average in the core multivariable model (β = 0.238, p = 0.023). However, morphologic variables explained only a modest proportion of hearing-threshold variability, so PCCT findings are best considered complementary to audiometry and MRI rather than standalone diagnostic markers.
