Superior semicircular canal dehiscence is an uncommon neurotological disorder in which the petrous temporal bone overlying the superior semicircular canal lacks bone. Its most common symptoms include amplification of internal sounds, autophony, tinnitus, sound- and pressure-induced vertigo, hyperacusis, oscillopsia, and hearing loss. This video presentation aimed to demonstrate endoscopic-assisted repair of superior semicircular canal dehiscence with middle fossa craniotomy.

Eleven patients with superior semicircular canal dehiscence, verified with temporal computed tomography, were enrolled in the study.

An endoscopy-assisted middle fossa approach was applied to all patients. Superior semicircular canal dehiscence was successfully repaired with an endoscope in 11 patients.

Endoscopic-assisted repair of superior semicircular canal dehiscence may be a superior approach compared with binocular operative microscopy.

To describe a case of asymptomatic superior semicircular canal dehiscence.

Clinical case report.

A 50-year-old man presenting with right-sided Ménière´s disease also showed an enhanced response on vestibular evoked myogenic potential testing for the left ear. Unilateral left-sided superior semicircular canal bone dehiscence was clearly visualised on a subsequent temporal bone computed tomography scan. These findings were consistent with superior canal dehiscence syndrome. However, the patient did not complain of any specific superior canal dehiscence syndrome symptoms. Given that vestibular evoked myogenic potential testing may detect asymptomatic forms of superior canal dehiscence, as noted in this case, such testing seems to exhibit reduced specificity for superior canal dehiscence syndrome.

An enhanced response on vestibular evoked myogenic potential testing in isolation appears to be a weaker indicator of superior canal dehiscence syndrome, and rather a marker of superior semicircular canal dehiscence.