Enlarged vestibular aqueduct syndrome in the pediatric population.

OBJECTIVE: To correlate clinical and audiometric findings with the radiologic appearance in patients with enlarged vestibular aqueduct.DESIGN A retrospective review of data from enlarged vestibular aqueduct patients identified in a pediatric hearing-impaired database of 1,200 patients. SETTING A tertiary care pediatric referral center.

PATIENTS: Subjects were included for study with a radiographic diagnosis of enlarged vestibular aqueducts in at least one ear by a pediatric neuroradiologist.

MAIN OUTCOME MEASURES: Audiometric evaluations and radiographic temporal bone measurements.

RESULTS: Seventy-seven patients were identified with an enlarged vestibular aqueduct with a male-to-female ratio of 1:1.5. Patients were followed for a mean of 34 months (range, 0-179 months). Hearing loss was bilateral in 87% of cases. Vestibular symptoms were present in only three (4%) of the patients. Three patients (4%) suffered a sudden decrease in hearing after mild head trauma. Borderline enlargement of the vestibular aqueduct was associated with varying degrees of sensorineural hearing loss. Ninety-seven percent (64 of 66) of ears in control subjects with no sensorineural hearing loss had normal vestibular aqueduct measurements at the midpoint and operculum. Overall, the audiogram remained stable in 51% of ears, fluctuated in 28%, and progressively worsened in 21%. Measurements of the vestibular aqueduct at the midpoint and the operculum did not correlate with the audiometric threshold or the audiogram configuration. However, mean vestibular aqueduct size at the operculum was significantly larger in those with a progressive loss when compared with those with a fluctuating or stable hearing outcome.

CONCLUSIONS: Overall, audiometric thresholds remained generally stable, with sudden deterioration of hearing after head trauma seen in only three male patients. Progression of hearing loss after head trauma was not a significant finding in our patient population. Vestibular aqueduct opercular size alone showed a direct correlation with the audiometric outcome. Borderline enlarged vestibular aqueduct measurements appear to be associated with sensorineural hearing loss.