[Enlarged vestibular aqueduct syndrome. A review of 55 paediatric patients]

Abstract

Introduction: Enlarged vestibular aqueduct (EVA) is the commonest congenital anomaly found with imaging techniques in paediatric sensorineural hearing loss (SNHL). Our aim was to describe clinical and audiological findings in paediatric hearing loss associated to EVA.

Methods: Retrospective review of 55 children with imaging-technique EVA findings from 2000 to 2009. Subjective and/or objective audiological tests were analysed and audiological findings related to clinical features were described.

Results: Thirty-seven patients (67.27%) showed bilateral EVA and 18 (32.72%) were unilateral. Hearing loss was bilateral in 46 (83.63%) patients and unilateral in 9 (16.36%). Mean age at diagnosis was 3.78 years. Fifty-three (96.36%) children showed SNHL (28 bilateral and profound), while 2 (3.63%) patients had mixed hearing loss. There were 3 cases of hearing loss progression, 2 fluctuations, 2 of them were asymmetric and 2 patients suffered from vestibular symptoms. Concomitant image findings were 6 cochlear hypoplasia, 2 enlarged internal auditory canals, 1 enlarged vestibule and 1 hypoplastic lateral semicircular canal. Six clinical syndromes were found (2 cases of Down's, and 1 each of Jacobsen, Pendred, Waardenburg and branchio-oto-renal). One child was positive for GJB2 mutation. Familial hearing loss was demonstrated on 12 (21.8%) cases.

Conclusion: The clinical picture of hearing loss associated to EVA is characterised by great variability. It should be included in the differential diagnosis of unexplained mixed hearing loss. Familial and syndromic findings have to be taken into consideration in the diagnostic evaluations of such patients. Knowledge about the natural history of this illness is needed so as to give parents prognostic information.