Cogan's syndrome is associated with?

Cogan's syndrome is seen in middle aged adults. The features include interstitial keratitis, acute tinnitus, veigo and deafness. Treatment is by usage of topical and systemic coicosteroids. Early treatment is necessary to prevent permanent deafness and blindness. Ref: Comprehensive Ophthalmology, A. K. Khurana, 7th edition, p114.