Relationship between ultra-high-resolution computed tomography score of oval window region involvement and audiometry in otosclerosis

Purpose

To assess the relationship between the ultra-high-resolution computed tomography (U-HRCT) score of oval window region (OWR) involvement and audiometry in otosclerosis.

Methods

This study enrolled patients with clinically suspected otosclerosis who underwent U-HRCT examination. The analysis included 71 ears from 50 patients (mean age, 38.0 [34.0–49.8] years). The ears were divided into the conductive hearing loss group (group A, 20 ears) and mixed hearing loss group (group B, 51 ears). The CT scores of bone involvement around the oval window (0, none; 1, <25 %; 2, 25 %–50 %; 3, 50 %–75 %; 4, >75 %) and stapes footplate involvement (0, none; 1, <50 %; 2, >50 %) were evaluated and summed to obtain the CT score of OWR involvement. The Mann–Whitney U test was used to compare the difference in the distribution of the CT score of OWR involvement between groups A and B. Spearman's rank correlation analysis was performed to evaluate the association between the CT score of OWR involvement and the mean air conduction (AC), bone conduction (BC) and air-bone gap (ABG).

Results

The CT score of OWR involvement in group B was significantly higher than that in group A (p = .014). The correlation coefficients between the CT score of OWR involvement and the mean AC, BC, and ABG threshold were 0.74 (p < .001), 0.52 (p < .001), and 0.48 (p < .001).

Conclusion

U-HRCT possesses the ability to clearly depict the OWR in otosclerosis. The U-HRCT-derived OWR involvement score of otosclerosis could reflect the type and degree of hearing loss.