Implantable Middle Ear Hearing Devices: A Review

Abstract

Implantable middle ear hearing devices (IMEHDs) were developed in an effort to improve on the limitations of traditional hearing aids. The last few years have seen significant advances in this technology with the emergence of several new devices, including fully implantable prostheses. As more patients are being implanted, experience with these devices has increased and refinements have been made. The indications also have expanded to include patients with mixed hearing loss in addition to those with pure sensorineural hearing loss, with application of the transducer to either the ossicles or the oval or round window. Fully implantable devices also are gaining ground, although most of these are relatively new and are still in the early stages of clinical application. Each device has its specifics in terms of design, indications, and implantation. Clinical outcomes also have varied, with some devices not surviving early clinical trials. This article reviews the mechanical concepts and design of IMEHDs, as well as the design, indications, and latest outcomes of the IMEHDs currently available on the market.