A titanium post is placed through the postauricular skin and anchored to the temporal bone where it osseointegrates. Long-term studies confirm safety and efficacy of the BAHA device. It has advantages over conventional bone conducting devices that exert pressure on the skin. However, the BAHA requires a lot of energy and delivers limited gain in amplification. Occasional skin problems also are associated with the percutaneous titanium post.
Extensive trials are in progress to determine their efficacy.
The rationale for development of implantable middle ear devices is several-fold. These devices provide improved fidelity through direct stimulation of the ossicles and improved comfort by allowing the ear canal to remain open. Feedback, one of the most annoying adverse effects of conventional aids, is almost completely eliminated with most implantable middle ear devices. Improved cosmesis through miniaturization and concealment of the components also is a benefit. Finally, some of these devices may allow the patient to continue receiving amplification while swimming or bathing.