Audiological findings in large vestibular aqueduct syndrome

An enlarged vestibular aqueduct is a congenital disorder causing early onse t and progressive hearing loss in children. This paper presents the audiolo gical findings at first presentation and the audiological evolution in 10 c onsecutive cases presenting with hearing loss and showing a large vestibula r aqueduct on imaging. The reported onset of the hearing loss is within the first few years of life. Most of the cases (80%) showed bilateral involvem ent. The sex ratio was 1. Patients presented on average at age 5 With a med ian hearing loss of 62 dB at the speech frequencies. The hearing loss was e ssentially asymmetrical with an interaural difference of 33 dB and it was a mixed type of hearing loss in 90% of the cases. The authors claim that the conductive component of this hearing loss is a pure cochlear conductive lo ss which may be pathognomonic for the disease. The presence of a conductive component in a child is easily misinterpreted as a middle ear ventilation problem or in case of good ventilation as an ossicular problem (type otoscl erosis). In addition and in contrast to most literature data, the authors d id not find evidence for stabilization of the hearing loss but they found a steady decrease of the hearing at an average rate of 4 dB/year, (C) 1999 E lsevier Science Ireland Ltd. All rights reserved.