Introduction:The implantable prosthesis of osseous conduction (BAHA) is deemed to be an excellent option in the auditory rehabilitation of patients with conductive and mixed hearing loss, unilaterally or bilaterally, and unilateral sensorineural hearing loss. It has been a good advantage over the conservative bone conduction apparatus and those of individual sound-amplifier apparatus (ISAA), when their usage becomes unfeasible because of chronic otitis externa, which has a hard clinic control. Objective:To introduce the first BAHA case performed in Brazil, as duly authorized by ANVISA (National Agency for Sanitary Surveillance), to rehabilitate the mixed hearing loss with occurrences of chronic otitis externa. Method:50-year-old female patient with right-ear moderate and left-ear severe hearing loss, bilateral tinnitus derived from otosclerosis, was submitted to 04 surgeries of stapedotomy and unable to use ISAA as a result of otorrhea and bilateral otalgia. The medical and audiological evaluation indicated the benefit of using BAHA. Having surgery been performed and BAHA implemented, the patient showed a significant improvement in audiometric thresholds, speech perception and distinction, as well as she declared to be extremely satisfied with the esthetic factor. Final commentaries: BAHA surgical process is safe, simple and swift, thus providing excellent audiological results and a higher degree of satisfaction to patients.

To our knowledge, this is only the third such case described in the literature. Considering that the vestibulocochlear nerve has been unable to be demonstrated in almost all cases of duplicated internal auditory canal (unilateral and bilateral), our case supports the hypothesis that vestibulocochlear nerve aplasia or hypoplasia leads to internal auditory canal stenosis. We consider this rare presentation of bilateral narrow duplication of the internal auditory canal to represent a contraindication for cochlear implantation.