Source: MED-EL

What happens if they fail the screening?

Don’t panic – this doesn’t mean they have hearing loss. It can be difficult to get a  esponse for three reasons:

  • Your baby was unsettled at the time of the test
  • The room was noisy
  • There was some fluid left in the ear from the birth process

The test will usually be repeated and if there’s still no response, your baby will be referred for an Automated Auditory Brainstem Response test.

Automated Auditory Brainstem Response test

This second screening test records your baby’s nerve response to sound. When sound vibrations reach the cochlea in your  baby’s inner ear, they are converted into electrical signals, which travel via  the hearing nerve to their brain. (See How hearing works for more detail).
Three small sensors are placed on your baby’s head and connected to computer equipment. Soft headphones are then placed over your baby’s ears and a series of clicking sounds are played. If your baby’s hearing is normal, the sensors detect a nerve response to sound along the auditory pathway. The test can take between five and 30 minutes.
If there’s no strong response, your baby will be referred for a full diagnostic hearing assessment.

Full diagnostic hearing assessment

This is usually carried out at a hospital audiology department. The tests will depend on your child’s age and stage of  development.
If your baby is younger than six months, there will probably be a more detailed version of the Automated Auditory Brainstem Response test, when different levels of sound are used and the audiologist interprets the results to find the quietest level of sound being picked up by the hearing nerves.

For information and support on hearing tests and diagnosis, contact the National Deaf Children’s Society Freephone Helpline on 0808 800 8880.

Tympanometry

This is a test to check how well the moving parts of your baby’s middle ear are working. A small earpiece is held gently in the ear canal while a pump causes a change in air  pressure. If everything is working correctly, the eardrum should move freely in and out with the change in pressure.

The earpiece measures this by checking the sound reflected by the eardrum. If the eardrum isn’t  moving freely, there’s likely to be some fluid or another problem with the  middle ear. This build-up of fluid is usually due to glue ear, known medically as otitis media with effusion (OME). It’s very common in young children and can  cause temporary deafness.

Behavioural tests

If your child is six months or older, behavioural tests may be carried out, which use toys and play and involve your child listening for a variety of sounds as part of a game. If your child hears the sound, they will turn their head and a visual ‘reward’ is activated, such as a toy that lights up or a puppet. Ears can be tested individually with the use of small earphones.

Pure tone audiometry

From about age three, children are actively  involved in testing. Sounds are played through headphones, earphones, or sometimes through a speaker (soundfield audiometry) and the child is asked to respond each time they hear a sound. Younger children are shown how to move a toy, say by putting a peg into a board, and older children are asked to say ‘yes’  or press a button.

Bone conduction tests

Rather than using air conduction, where sound waves travel down the ear canal, from the outer ear to the cochlea, bone conduction tests can be used. A small vibrating device is placed behind the child’s ear, passing sound vibrations directly to the inner ear through the bones in the head and bypassing the ear canal and middle ear. This can help determine what type of  hearing loss your child has.

What to do now!

Why not speak to one of our hearing implant recipients? They know what you’re going through and can answer your questions.