Cogan's syndrome: an oculo-audiovestibular disease.

Typical Cogan's syndrome is a rare disease of young adults consisting of flares of interstitial keratitis and sudden onset of Ménière-like attacks (nausea, vomiting, tinnitus, vertigo and hearing loss). Life-threatening aortic insufficiency develops in 10% of reported cases. Atypical Cogan's syndrome (audiovestibular dysfunction with other types of inflammatory eye disease) is associated with vasculitis in 20% of cases and has a less favourable prognosis than typical Cogan's syndrome.