Unilateral Enlarged Vestibular Aqueduct in Children

Abstract

Objective: 1) Describe the likelihood of contralateral hearing loss (HL) in patients with unilateral enlarged vestibular aqueduct (UEVA). 2) Detemine the positve predictive value of genetic testing in patients with UEVA. 3) Determine the correlation of temporal bone measurements in patients with UEVA.

Method: Patients were identified from a database of children with sensorineural hearing loss (HL) and enlarged vestibular aqueduct (EVA) between 1998 and 2010. A group of patients with unilateral HL without EVA was also identified. Outcomes measured were HL phenotype, laterality of EVA, midpoint and operculum measurements, and genetic tests.

Results: Fifty-five percent of patients with UEVA had HL in the contralateral ear. There was no difference in the rate of HL progression in patients with bilateral and unilateral EVA (P = .1). However, both EVA groups had higher rates of progression compared to patients with unilateral HL alone. A correlation was shown for the presence of HL at 250 Hz and the risk of more severe HL and progressive HL. Patients with bilateral EVA and SLC26A4 mutations had a higher rate of progression than patients who had no mutations (P = .02). No patients with UEVA had Pendred syndrome.

Conclusion: Children with unilateral EVA have a significant risk of HL progression. Hearing loss in the contralateral ear is common, suggesting that unilateral EVA is a bilateral process. Temporal bone measurements, HL severity, and HL at 250 Hz were correlated with the risk of progressive HL.