Cochlear Implant in Far Advanced Otosclerosis

Background: Otosclerosis is a complex temporal bone confined abnormality in which osteospongiosis causes replacement of healthy otic capsule bone with otosclerotic tissue. The disease causes either a conductive, sensorineural or combined hearing loss according to extension and localization of the lesions. Far Advanced Otosclerosis is presented with a sensorineural hearing loss and air conduction thresholds exceeding 85 dBHL. Cochlear implant is one of the best available options for this condition but a detailed preoperative evaluation should be performed.
Objective: Review our experience with implanting patients with far advanced otosclerosis.
Methods: retrospective review including imaging analysis, audiological assessment, presence of previous stapedotomy, surgical failure and facial nerve stimulation.
Results: eight cases of far advanced otosclerosis were analyzed in which we found six class 3, and two class 2C CT scan alterations (Rotteveel). Two patients had facial nerve stimulation and in one patient the electrode could not be inserted. Two patients were submitted to previous stapedotomy. The average Speech Perception Threshold was 85dBHL and speech discrimination was 40%. All patients at the time of cochlear implantation had previous minimal benefit with conventional hearing aids.
Conclusion: Cochlear implantation has proved to be an successful therapy option in far advanced otosclerosis, however all patients should undergo a careful preoperative evaluation to enhance positive outcomes and minimize complications.