Audiologic characteristics of patients with the X-linked stapes gusher syndrome

Abstract

There is evidence that normally the cochlear aqueduct is the major route for the pressure equilibrium between the cochlear and cerebrospinal fluids (Schuknecht and Gulya 1986; Marchbanks and Reid 1990). If the aqueduct is large, the inner ear becomes susceptible to damage by sudden cerebrospinal pressure variations that result from every day events. Customarily, the resistive nature of the aqueduct and the compliance of the cochlear windows attenuate any sudden pressure waves that enter the cochlea and thus prevent damage to the cochlea (Marchbanks and Reid 1990). However, in the case of congenital malformations of the audiovestibular system, other routes may also become important for pressure equilibrium and may allow the transmission of potentially harmful intracranial pressure peaks to the cochlea. The most common malformation is Mondini’s dysplasia, characterized by anomalies such as a short dilated cochlea and vestibule, malformed semicircular canals, sometimes a wide internal auditory meatus and perilymphatic fistula (Schuknecht 1980). Generally, profound deafness is found in affected ears.