BACKGROUND AND PURPOSE: Vestibular schwannomas (VSs) are benign neurogenic tumors commonly associated with progressive unilateral hearing loss, tinnitus, and vestibular symptoms. Growing evidence links signal changes in the VS-adjacent labyrinth with sensorineural hearing loss. This study seeks to quantify the association of labyrinthine signal on postgadolinium 3D-FLAIR imaging correlates with hearing loss and to evaluate potential longitudinal changes over time. MATERIALS AND METHODS: Selected patients were identified from a prospectively maintained VS registry. Mean signal intensity ratios of the bilateral labyrinth and pons were measured on 3D-FLAIR postgadolinium MRI. Correlations with paired audiometric data, including pure tone average (PTA), word recognition score (WRS), and American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) hearing class within 1 year, were evaluated. RESULTS: One hundred twenty-five studies obtained from 2015 to 2022 among 66 patients undergoing observational management for sporadic VS were analyzed. Increased signal intensity was noted in the VS-affected labyrinth/contralateral labyrinth (mean ratio 1.56, SD 0.58). Increased signal intensity was associated with increased PTA on both labyrinthine (correlation coefficient [CC] 0.20, CONCLUSIONS: Increased 3D-FLAIR postgadolinium labyrinthine signal is associated with sensorineural hearing loss
however, its relationship with hearing trajectory remains unclear. Overall findings suggest that while postgadolinium 3D-FLAIR techniques are sensitive to inner ear involvement associated with VS, the driving mechanism and their temporal relationships with labyrinthine signal intensity and hearing impairment remain unknown.