Hearing aids (bone-anchored)

  • Hearing aids amplify sound, that is, they increase the volume of sound reaching the inner ear (cochlea). Conventional hearing aids are the best choice of hearing aid for most people who are deaf.
  • Some people find they cannot use normal hearing aids. This may be because they suffer from frequent infections which block the ear, or have very narrow ear canals. For these people, a small titanium screw can be inserted into the side of the skull and a bone-anchored hearing aid attached. The hearing aid vibrates in response to sound. This vibration is transmitted by the skull to the inner ear (cochlea) to produce a sensation of sound. You do not feel as if your head is shaking.

  • The operation can be performed under local or general anaesthetic. The titanium screw is carefully drilled a few millimetres into the thick outer surface of the skull behind and above the ear. You will usually be able to go home the same day.
  • For 4–6 weeks the area is kept covered by a dressing which is changed every few days while the skin heals. It is typically 3 months before you can start using the hearing aid, to ensure that the screw is firmly integrated into the skull bone and will not be displaced when you clip the hearing aid on and off.
  • The skin around the screw must be kept very clean, otherwise it can become infected. Infections can often be treated with antibiotics, but a severe infection may mean the screw must be moved in another operation.

    Hearing aids (conventional)

    • A hearing aid amplifies sound, that is, it increases the volume of sound reaching the inner ear (cochlea).
    • The most common type of hearing aid rests behind the ear and is attached to a plastic mould which fits snugly in the ear. The hearing aid consists of a small microphone, a battery, and an amplifier that feeds amplified sound into the ear canal.Hearing aids can help most people with hearing loss, although they never restore normal hearing.
    • Their biggest disadvantage is that they amplify all sounds, including background noise. Often the first sign of mild hearing loss is difficulty understanding speech against background noise, and a hearing aid is unlikely to help.
    • Hearing aids come in many different shapes and sizes, ranging from ‘behind-the-ear’ aids to aids that fit inside the outer ear or even tuck invisibly deep in the ear canal. The main advantage of smaller hearing aids is that they are less obvious to other people.
    • All hearing aids now rely on digital technology. They can alter sound in many more ways than older-style hearing aids, for example by boosting the frequencies at which we hear speech. Digital technology can also help produce better overall sound quality and reduce feedback and background noise interference.
    • Special aids are available for people who find conventional hearing aids unsuitable. These include body-worn hearing aids, hearing aids incorporated into spectacle frames, and bone-conducting hearing aids.