Auditory Characteristics in Children With Enlarged Vestibular Aqueduct.

Objective: Enlarged vestibular aqueduct (EVA) is the most common radiographic finding in children diagnosed with congenital sensorineural hearing loss (SNHL). Many institutions use the Cincinnati criteria for diagnosis: width ≥2.0 mm at the operculum and/or ≥1.0 mm at the midpoint. Our goals are to expand our understanding of EVA by examining the audiometric and auditory brainstem response (ABR) characteristics of a large population of children with EVA and hearing loss.

Study design: Retrospective chart review.

Setting: Tertiary-care children's hospital.

Patients: All children diagnosed with EVA from 2006 to 2016.

Interventions: Diagnostic.

Main outcome measures: Vestibular aqueduct measurements were taken at the operculum.

Results: One hundred six patients were included (63 females; 60 bilateral EVA). The age of hearing loss diagnosis was significantly younger in patients with bilateral EVA compared with unilateral (0.0 [0-3] yr versus 5.0 [0.9-7.0] yr, p = 0.001). The most common pattern seen on ABR was SNHL-like (57%), followed by large wave I pattern (28.6%), followed by auditory neuropathy spectrum disorder (14.3%). Patients with bilateral EVA were more likely to have progressive hearing loss compared with patients with unilateral EVA ( p = 0.001). There was no correlation between EVA size and hearing stability or between EVA size and pure-tone average at the time of diagnosis.

Conclusion: There is a wide range of clinical manifestations of EVA, though we found no significant correlation between size and progressiveness or severity. The clinical significance of a large wave I tracing on ABR is not fully understood and warrants further research.