[Characterization of bilateral superior canal dehiscence]

In the superior canal dehiscence syndrome, patients can have sound- or pressure-induced vertigo and oscillopsia. They may also present conductive hearing loss or higher than normal bone conduction thresholds. Clinical manifestations are due to the effect of a third mobile window in the inner ear created by the dehiscence. Diagnosis is based on clinical manifestations, vertical and rotatory nystagmus induced by sound and pressure reflecting SSC stimulation, reduced threshold and increased amplitude of vestibular evoked myogenic potentials (VEMP) and temporal bone CT scan images showing the SSC dehiscence. Characteristic eye movements can be recorded with the scleral search coil technique.