[Cogan syndrome with audiovestibular disfunction: 2 cases report].

We describe a case of Cogan syndrome in patients with clinical manifestations, related examinations and diagnosis,treatment,and review of relevant literature. Both patients had bilateral moderate to severe sensorineural hearing loss. The collateral function test showed that there were bilateral semicircular canal paresis,and the head impulse test had a bilateral gain value between 0.09 and 0.55. It showed obvious compensatory saccade wave, the head impulse suppression test bilateral no anti-compensation saccade wave.Cogan syndrome is a rare syndrome with unspecific symptoms and early diagnosis is difficult. However, the involvement of the auditory vestibular systems are often poor prognosis and needs to be diagnosed by early diagnosis and treatment.