The Large Vestibular Aqueduct Syndrome

TLDR

The study analyzed radiographic data from 50 patients with vestibular aqueducts larger than 1.5 mm. In 60 % of these patients, additional inner‑ear anomalies were found, the enlarged aqueduct likely reflects arrested development, with sizes ranging 1.5–8 mm, a 50/3700 incidence, bilateral involvement twice as common, a 3:2 female‑to‑male ratio, and most cases linked to congenital hearing loss.

Abstract

The radiographic observation of 50 patients, each having an enlarged (greater than 1.5 mm. diameter) vestibular aqueduct, are analyzed. In addition to the aqueduct other associated inner ear anomalies have been identified in 60% of this population including: enlarged vestibule (14); enlarged vestibule and lateral semicircular canal (7); enlarged vestibule and hypoplastic cochlea (4); and hypoplastic cochlea (4). The large equeduct then presumably represents an arrested phase of inner ear development common to all 50 cases. Only 8 of these cases may fall into the Mondini or Mondini-Alexander classification wherein cochlear abnormalities have been identified. The size of the aqueduct ranged from 1.5 to 8 mm. in the anteroposterior diameter; the clinical incidence is 50 in 3700 consecutive cases referred for inner ear tomography. Bilateral involvement is twice as common as unilateral with a female to male predominance of 3:2. Most cases are associated with congenital hearing losses.