Design of a magnetic coupling type implantable middle ear hearing aid

A new type of implantable middle ear hearing aid, which consists of an external loop coil, a small magnet and simple external device, is proposed. The internal device of the new type consists of only a small magnet. The external device doesn't have to be positioned behind the ear or ear canal. Also, it is excellent from a cosmetic viewpoint, because the external device can be hidden within upper garment and collar of clothes. The can be bigger than conventional type a, which means it has longer battery life. Therefore, the battery doesn't need to be changed very frequently. The surgical operation is easier than conventional type. Only a small magnet is transplanted in the middle ear. Gap calibration of the transducer isn't necessary. We investigate the performance of the proposed implantable middle ear hearing aid. We found that the proposed device is appropriate for mild and severe hearing impaired persons.