[Dehiscence of the superior semicircular canal: report of a case and bibliography review].

We present a case of deficiency of the superior semicircular canal (SSCD) in a 37 years old patient that came to us because of episodes of subjective vertigo in response to intense sounds (Tullio phenomenon). The audiometry, electronistagmography, timpanometry and stapes reflexes were normal and the fistula test was negative. The CT scan showed an absence of bone overlying the superior semicircular canal (SSC) of the right ear and the left ear was normal. When both ears were exposed to intense sounds, only the right one presented vertigo was, without nystagmus.