Sensorineural hearing loss is not seen in superior semicircular canal dehiscence syndrome (SSCDS)
The Tulio phenomenon is seen in SSCDS. Tulio phenomenon refers to the sound or pressure induced vestibular activation.
Superior semicircular canal dehiscence syndrome occurs due to the third window effect that gets
created because of the thin/ dehiscent wall of the superior semicircular canal. This causes endolymph in the labyrinthine system to move in relation to sound or pressure, causing an activation of the vestibular system. It is usually diagnosed in middle
aged individuals and no racial or sexual predominance is seen.
- Patients present with noise or pressure-induced dizziness. Some may complain of chronic imbalance.
Avoidance of noisy environments is adopted by the patient. Also, some may have gaze-evoked tinnitus
and/ or hyperacusis.
-Patients with SSCDS usually have a normal gait test, Romberg’s test, Fukuda test, Dix hall pike maneuver
but the fistula test is positive (Hennebert Sign) and the Barany noise box can be used for inducing vertigo. - Noncontrast HRCT of the temporal bone can demonstrate the defect and the condition is usually
treated by surgery if there are severe disabling symptoms. Else, conservative medical management
is done.