Many children who are deaf or hard of hearing (DHH) use devices that amplify sound. Bone conduction hearing aids (BCHAs) look different to regular hearing aids because they do not sit inside the ear. Here’s what you need to know about BCHAs, including how they work and how to care for them.
A BCHA is a type of hearing aid that transmits sound waves through the bones in the head directly to the cochlea (inner ear). They can be good for children with certain types of hearing loss, or when problems with the outer or middle ears (such as chronic ear infections) mean a regular hearing aid is not suitable.
BCHAs have two parts: a small implant that is surgically inserted into the bone behind the ear and an external sound processor. The sound processor is connected to the implant either via a magnet or a small fixture that protrudes through the skin (known as ‘abutment’).
Some BCHAs do not use a surgical implant, instead, the device sticks to the skin behind the ear or is held in place by a headband.
In normal hearing, sound travels from the outer ear to the middle ear to the cochlea. BCHAs bypass the outer and middle ears.
The sound processor picks up sounds and turns them into vibrations. These vibrations are transmitted to the implant, which send them through the head bones directly to the cochlea. The cochlea converts the vibrations into electrical impulses, which are sent to the brain via the hearing nerve.
A BCHA needs special care and maintenance. If a child has one, they or their caregivers are responsible for looking after it. Understanding some basics can give you peace of mind.
Bond conduction hearing aids only work if the cochlea is functioning. They are different to cochlear implants, which have electrodes in the cochlea itself.