[Stapedovestibular otospongiosis beginning in the cochlea. Apropos of 3 cases].

Stapedovestibular ankylosis developed after a prolonged course of pure perception deafness in 3 patients, suggesting possible secondary fixation of the stapes from otospongiosis restricted to the cochlear up to that time. A precise diagnosis of pure cochlear otospongiosis is always difficult to make, its presence usually being supposed rather than confirmed in spite of clinical, audiometry and radiology data, except in those few cases where secondary ankylosis of the foot of the stapes occurs. These findings suggested the need for regular audiometric surveillance of all patients with perception deafness.