[Clinical analysis of 95 patients with large vestibular aqueduct syndrome]

To investigate the occurrence, genetic inheritance, and hearing loss conditions of large vestibular aqueduct syndrome (LVAS), and to measure the width of external aperture of vestibular aqueduct (VA) of LVAS, and to analyze the relationship between the hearing loss and the width of external aperture.

A retrospective review was conducted by the history, auditory, and vestibular function examinations in 95 patients (190 ears) of LVAS. The width of VA was measured by CT scanning criterion of each LVAS patients in the past 10 years (from 1992 to 2002).

In 95 patients, there were male 65 cases and female 30 cases. The male cases was more than the females by a ratio of 2.2:1. Twelve cases (12.6%) would have familial genetic history. The average of the consult age was 7.6 years (range from 1.2 to 39 years). The most patients were misdiagnosed, the hearing deterioration originated from mild head trauma in 21 cases (22.1%), the hearing loss after common cold in 13 cases (13.6%). Nine cases (9.5%) misdiagnosed as sudden hearing loss, 5 cases (5.3%) as ototoxic hearing loss of Aminoglycoside antibiotic. The profound hearing loss was found in 172 ears (92.4%). The average width of external aperture of LVAS was 7.5 mm +/- 1.2 mm (mean +/- s, 77 cases, 154 ears). The level of hearing loss did not proportional to the width of VA. The hearing impairment could be derived from protein-rich endolymph refluxed into the cochlear and vestibule.

The LVAS is distinct clinical entity characterized by fluctuate and progressive SNHL. The diagnosis depends upon the CT scan and MR image. If the hearing fluctuated and subsequently improved, the children were kept under conservation treatment. If the significantly decreased of hearing effected school performance, the cochlear implant might be considered.