Hearing aids

This factsheet is for people who are considering getting a hearing aid, or who would like information about them.

Hearing aids are electronic devices that are worn either in or behind your ear. They make sounds louder and clearer so that you hear them comfortably if you're having problems with your hearing.

Availability and use of hearing aids may vary from country to country.
 
How the ear works
About hearing aids
Wearing a hearing aid
Caring for a hearing aid
Living with a hearing aid

How the ear works

About hearing aids

A hearing aid is a small device that you wear in or behind your ear. It can make some sounds louder so that you can communicate more effectively. If you're having problems with your hearing, a hearing aid may help increase how much you can hear. Hearing loss is common and can affect people of any age. According to the World Health Organization, hearing loss and deafness affects at least 275 million people worldwide.

A hearing aid can help if your hearing loss has been caused by damage to the hair cells in your inner ear (sensorineural hearing loss). It may also be helpful for some types of conductive hearing loss – where sound is unable to pass from your outer ear to your inner ear because of a build-up of wax, or because you have fluid in your ear. If you have tinnitus (buzzing or ringing in your ears), a hearing aid may help you to notice it less.

Having a hearing test

If you think a hearing aid may help with your hearing, speak to a doctor for more advice. He or she may refer you to an audiologist (a healthcare professional who specialises in identifying and treating hearing disorders). You will need to have a hearing test to find out what sort of hearing loss you have and whether or not a hearing aid will be helpful.
Your audiologist will ask you questions about your hearing and examine your ears. He or she will ask you to listen to sounds through headphones at different pitches and volumes. Every time you hear a sound, you press a button.

The audiologist may then ask you to wear a headband with a vibrating pad that transmits sounds to the cochlea in your inner ear on both sides of your head. The cochlea turns sounds into nerve impulses and sends them to your brain, which interprets the vibrations as sounds. Again, you press a button each time you hear something.

For children under the age of four, it can be difficult to get reliable results with these techniques, so a paediatric audiometric assessment can be used, which often requires more than one audiologist and can take longer.
Your audiologist will discuss your test results with you and advise you if a hearing aid is likely to help you, or if a different treatment will be more beneficial.
Please note that availability and use of specific tests may vary from country to country.
 

How hearing aids work

A hearing aid is made up of a microphone, amplifier and speaker. The microphone picks up sounds and converts the sound waves into electrical signals that are sent to the amplifier. The amplifier makes the sounds louder and sends them to your ear through the speaker.

Your hearing aid can be tuned into certain sounds you're struggling to hear without making noises that are already loud even louder.

Hearing aids won't make your hearing perfect but will help you hear everyday sounds like the telephone, doorbell and kettle boiling.
 

Types of hearing aid

Hearing aids are available in analogue and digital and come in various shapes and sizes.
 

Analogue hearing aids

Analogue hearing aids are traditional hearing aids that use a transistor (a device that increases the power of a signal) to increase the volume of the sounds picked up by the microphone. Your audiologist will set the hearing aid so that the sounds you're having difficulty hearing are made louder and sent into your ear through the speaker.

Analogue hearing aids are usually cheaper than digital ones, but have almost been completely replaced by digital aids, which are easier to customise to your needs.

 
Digital hearing aids

Digital hearing aids contain a mini-computer. Sounds picked up by the microphone are first broken up into very small, distinct units. The mini-computer is programmed to make some of the units louder and some of the units quieter depending on your specific hearing difficulty. Some digital hearing aids can be adjusted to suit different situations, such as a quiet library or a noisy bar.

Most hearing aid manufacturers only produce digital hearing aids.
 

Wearing a hearing aid

There are a number of different styles of hearing aid. The style you have will determine where you wear your hearing aid. Some examples are listed below.

• Behind-the-ear hearing aids have a plastic case that sits behind your ear and an earmould that fits into your outer ear. Open fit, behind-the-ear hearing aids have a narrow tube that inserts into your ear canal instead of an earmould. This leaves your ear canal open so is a good choice if you tend to get a build-up of earwax. It can make sounds more natural. Open fit, behind-the-ear hearing aids are suitable if you have mild to moderate hearing loss.
• In-the-ear hearing aids fit entirely within your outer ear and may be used if you have mild to severe hearing loss. These hearing aids are usually less noticeable than behind-the-ear hearing aids. Some in-the-ear hearing aids have a part called a telecoil that makes telephone conversations easier to hear. In-the-ear hearing aids aren't generally used by children because the casings need to be replaced as their ear grows.
• Canal hearing aids fit into your ear canal and come in two styles. In-the-canal hearing aids are made to fit the size and shape of your ear canal. Completely-in-canal hearing aids are smaller and less visible than other styles of hearing aid. They are almost totally hidden inside your ear canal. Canal hearing aids may not be suitable if you have severe hearing loss or have frequent ear infections. This is because they are very small and can't hold a very powerful amplifier.
• You may benefit from a bone conduction hearing aid if you have conductive hearing loss and you're unable to wear one of the more common styles of hearing aid. This could be because you have had ear canal or middle ear problems, such as frequent ear infections or surgery. Bone conduction hearing aids work by passing sound through your skull directly to your inner ear, missing out your outer and middle ear.
• If you have vision problems or find it difficult to work small controls, you may find a hearing aid that you wear on your body useful. This type of hearing aid has a small box that you can put in your pocket or attach to your clothes. The box is connected to a microphone by a lead, which can be very powerful.

Caring for a hearing aid

Your audiologist will give you instructions about how to care for your hearing aid so that it works well and lasts as long as possible. You may find the following tips helpful.

• Wash your behind-the-ear hearing aid every night in warm soapy water.
• Clean your in-the-ear hearing aid regularly with a soft, dry cloth to remove any earwax. It's important that your in-the-ear hearing aid doesn't come into contact with any liquid.
• When you're not wearing your hearing aid, store it carefully in a box in a cool, dry place.
• Turn off your hearing aid when you're not using it.
• Change the batteries as soon as they stop working.

Living with a hearing aid

You may find it takes a while to get used to wearing a hearing aid. It's important to wear it as much as possible and practise using the controls and different settings. Your audiologist will be able to give you advice about using your hearing aid in different environments. He or she can also help if you have any problems with your hearing aid.