Implantable hearing aid using an ossicular vibrator composed of a piezoelectric ceramic bimorph: application to four...

Direct driving of the stapes by an ossicular vibrator composed of a piezoelectric ceramic bimorph is the key functional mechanism of the partially implantable hearing aid reported in this article. Acoustic signals from a microphone are transmitted to the vibrator by means of electromagnetic induction. The devices were implanted into four patients with mixed deafness due to chronic otitis media. In the first patient, the device has continued to function for two years. The highly efficient sound transmission achieved by the direct driving of the stapes produced excellent sound perception. The functional principle, surgical procedure, and indications for this new device for hearing rehabilitation are described together with the clinical results obtained in the four patients.