Abstract
Sound- and/or pressure-induced vertigo due to bone dehiscence of the superior semicircular canal was first described by Minor et al. in 1998, and was named superior canal dehiscence syndrome (SCDS). A 27-year-old man presented with dizziness and oscillopsia induced by loud sounds. A pure-tone audiogram showed right conductive hearing loss at low tone frequencies with hypersensitivity to bone-conducted sound at low frequencies. Vestibular evoked myogenic potentials (VEMP) testing demonstrated large amplitudes in the right ear. A high-resolution computed tomography scan of the temporal bones revealed a dehiscence of bone overlying the superior canal. The image showing dehiscence was taken at an angle approximately 45° to the sagittal plane, in close parallel alignment with the superior semicircular canal. Based on these findings, SCDS was suspected as the cause of the dizziness.