The Mondini dysplasia--from early diagnosis to cochlear implant.

The early diagnosis of the Mondini dysplasia by means of electrocochleography and temporal bone polytomography, and the prevention of further hearing loss through the endolymphatic subarachnoid shunt operation, brought new data on the follow-up of patients with this malformation. They were found to present specific medical and educational problems. Children with concomitant serous otitis media were found to develop profound hearing loss following insertion of ventilation tubes due to fistula formation in the oval window. One cochlear implant, employing the technique developed by William House, was performed in a 22-year-old patient in whom the dysplasia had not been previously recognized. The importance of early diagnosis and treatment will be emphasized.