Sensorineural hearing loss in patients with large vestibular aqueduct

Abstract

In examining 181 patients (327 ears) with sensorineural hearing loss of unknown etiology and 25 people (50 ears) with normal hearing by high-resolution computed tomography (CT), the image of the large vestibular aqueduct (VA) was defined as being a visible large aperture (> or = 4 mm), and small distance between vestibule and traceable part of the VA nearest to the vestibule (> or = 1 mm). The large VA was found in 13 patients (23 ears, 7.0%); it was relatively frequent following hypoplastic cochlea (33 ears, 10.1%) in all the inner ear anomalies detected. In patients with large VA, high-frequency hearing was affected more than low frequency, and history of sudden hearing loss was observed frequently (61% of ears with large VA), which was found to be triggered by characteristic episodes such as minor head trauma, etc. Those clinical features were observed more in those without cochlear anomaly than in those accompanying cochlear anomaly. Pathogenesis of sensorineural hearing loss and characteristic fluctuation of hearing in those patients are discussed.

Enlarged Vestibular Aqueduct in Congenital Non-Syndromic Sensorineural Hearing Loss in Egypt

“…Moreover, there was no correlation between the size of the VA Op and Mp and the audiometric threshold at different frequencies. Many studies [3,11,20,22,32,33] reported similar results. Contrary to these reports, Antonelli et al [34] reported a significant correlation between the VA size and severity of hearing impairment in patients with EVA and cochlear dysplasia.…”

“…This is a relatively high incidence when compared with that reported in the literature [3][4][5][6][7][8]12] and might be accepted in a pilot study with a limited number of patients. Developmental growth of the VA throughout infancy and early childhood has been described, indicating that EVA may result from abnormal postnatal and pre-adolescent development and reaches the adult size at 3-4 years [13,14].…”

“…Several authors [2,3,19,22,29] suggested the potential causes of SNHL in patients with isolated EVA including hydro-electrolyte imbalance of inner ear fluids resulting in accumulation of excess endolymph. The resulting volume or pressure effect participates in an enlarged endolymphatic duct and sac.…”

“…These anomalies are presented either isolated or in combination. Previous studies reported an incidence of isolated EVA ranging from 3.7 to 11.4% [3][4][5][6][7][8].…”

Síndrome do aqueduto vestibular alargado: relato de 3 casos e revisão bibliográfica

“…One of the many hypotheses considered are affection to homeostasis in endolymphatic circulation as a result of ductal enlargement, with consequent damage to cochlear neuroepithelium 6 . Another hypothesis is whether enlargement of VA and endolymphatic sac would not be an isolated anomaly, but rather a continuity of the cochleovestibular malformation.…”