Background: Central lucency of the bony island of the lateral semicircular canal (LSCC) is commonly found in patients with congenital severe-to-profound sensorineural hearing loss (SNHL).
Objective: Exploring the significance of bony island lucency of LSCC in congenital severe-to-profound SNHL patients.
Material and methods: Retrospective measurements of the inner ear structures were made on axial temporal bone CT scans from 182 (364 ears) congenital severe-to-profound SNHL patients and 50 (100 ears) tympanic membrane perforation (TMP) patients.
Results: The incidence of bony island lucency of LSCC was 46.7% in the congenital severe-to-profound SNHL group and 0% in the TMP group. There was a statistically significant difference in inner ear structures among congenital severe-to-profound SNHL patients with normal inner ear structure and bony island lucency of LSCC, congenital severe-to-profound SNHL patients with normal inner ear structure and no bony island lucency of LSCC, and TMP patients. The importance of the bony island lucency of LSCC was further confirmed through multiple linear regression analysis.
Conclusions and significance: Bony island lucency may have significance in congenital severe-to-profound SNHL and may be a manifestation of largely overlooked SCC malformation or hypoplasia of the inner ear.
Keywords: Bony island lucency; computed tomography; inner ear; lateral semicircular canal; sensorineural hearing loss.