الفهرس 
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Abstract
Theprevalence of hearing loss increases with age and over one third of people older than 65 years have a significant hearing loss. Only approximately 20% of people with hearing loss seek assistance from hearing aids. Of these, as many as 16.2% do not wear their devices. Several types of devices can be considered implantable hearing devices. These include implantable middle ear devices, cochlear implants, bone-anchored hearing devices, and auditory brainstem implants. The technique of cochlear implantation was the first method which allowed replacement of a sense organ by a (partially) implantable electronic prosthesis. All cochlear implants consist of five basic parts a microphone, speech processor, transmitting coil, internal receiver/stimulator, and an electrode array. It is indicated in children more than 12 months with severe to profound bilateral sensory-neural hearing loss and have little or no benefit from hearing aids. And indicated in adults with at least moderate hearing loss in the low frequencies and a profound hearing loss in the mid to high speech frequencies bilaterally and have also little or no benefit from hearing aids. The auditory Brainstem implant (ABI) is a new hearing prosthesis designed for stimulation of the inferior colliculus. It differs as compared to the cochlear implant only by the electrode design itself and its anatomical location where the electrode has to be placed. The most 83 common indication for an ABI is in patients with NF2, other indications include deaf patients who cannot sufficiently benefit from cochlear implants such as people with ossified cochleae after meningitis. The Bone Anchored Hearing Aids (BAHA) consists of 3 parts: a Titanium implant, an external abutment and a sound processor , it is surgically implanted for patients who are 5 years of age or older, have conductive hearing loss or mixed hearing loss. A significant interest in Implantable Middle Ear Hearing Devices (IMEHD) has emerged over the years. The basic components of an IMEHD consist of an acoustic signal detector (receptor), a transmission link, and an actuator that vibrates the ossicular chain (effector). It is used with patients who are noncompliant with conventional hearing aides, do not receive significant benefit from conventional aides, or are not candidates for cochlear implants. Arabic.