Bone Conduction Hearing Aid (BCHA)

This is for the benefit of people who suffer from a severe conductive hearing loss, or abnormalities of the ear, where the wearing of an air conduction aid is not possible, or if a person suffers from ear infections, the sound is carried through bone conduction.

CROS

These are not a hearing aid as such they are used when the patient has good hearing in one ear and total or near total deafness in the other. The CROS hearing aids collect the sound from the dead ear and then transfer it to the other ear either by a cable or by radio signal.

BiCROS

This is simply a CROS hearing aid with another microphone placed on the better ear side. This is useful when a person suffers from a hearing impairment in one ear and an unaidable loss in the other ear.

Body Worn Hearing Aids

These are used when the loss is very severe or profound and usually cannot be assisted by conventional behind the ear hearing aids. They are also very useful for people with severe dexterity problems. The main box can be worn around the neck or can be attached to a belt or a pocket.

Spectacle Hearing Aids
 
These aids are now available as a very discreet option, because of the development of slim tube fittings. Bone conduction spectacles are also available as a more fashionable option and the digital version is available in various styles and colours. Most spectacle hearing aids are bone induction aids rather than the more common air conduction. The sound is passed from the hearing aid through the arm of the pair of glasses and into the mastoid bone, and from here it is transmitted to the inner ear. People that hate the idea of having something in their ear find these useful. Using bone conduction as an input may be advised for those with conductive hearing loss, but it is not as effective as a functioning eardrum and middle ear, so patients with the more common sensorineural hearing loss would be better advised to use a conventional hearing aid.