As children grow, different hearing tests will be used.
Birth to 6 Months of Age
Auditory brainstem response (ABR) testing is the best test available for newborns and infants up to 6 months of age that can provide information about the softest level of sound the ear can hear.
ABR testing gives information about the amount of hearing loss that is present at different pitches. This is also known as "Frequency-Specific ABR". For babies up to five months of age, ABR testing can be attempted while a baby is sleeping naturally.
Sounds are played to the baby's ears and band-aid like electrodes are placed on the baby's head to detect responses. Sounds are presented to the ears using small earphones. The electrodes pick up responses from the hearing nerve and a computer measures the responses to identify babies who have a hearing loss.
Infants and Toddlers (6 months – 2 years)
Visual Reinforcement Audiometry (VRA) tests provide information about a child's hearing in both ears across different pitches. Sounds are presented through earphones or a loudspeaker and the child responds by looking at animated toys or videos that are paired with the sounds. Test results are graphed on an
audiogram.
Young Children and Preschoolers (2 - 5 years)
Conditioned Play Audiometry (CPA) tests provide information about a child's hearing across pitches in both ears. With this technique, the children perform a game-like activity every time a sound is heard. For example, the child is prompted to drop a block in a bucket when a sound is heard. Sounds are usually presented through earphones and results are graphed on an audiogram.
Hearing Tests for Children of All Ages
In addition to the tests already explained, other tests may be used at all ages:
Tympanometry
Tympanograms
Kendell Simms, Au.D, CCC-A, Audiologist
A tympanogram is a test that we use in audiology to help us know how the ear drum is working. The tympanogram does introduce a sound to the ear, but it is not a hearing test in and of itself. We use it most often in children to tell us if there is fluid behind the eardrum or if a child has gotten a tube placed in the ear then we use it to make sure that tube is working and is not blocked with fluid.
How does a tympanogram work?
The test is very easy. We put a little earphone in the child's ear and we press a button and it introduces a little bit of pressure and a little sound. It doesn't hurt. And that makes the ear drum try to move. When the ear drum is moving normally and there is no fluid and everything is working in the middle ear, it draws us a type A which is a mountain peak. When there is fluid it does kind of a flat line or a hill. When the tube is open it can draw any sort of line, we are looking at the numbers in that case. We are looking for a nice big volume that tells us the tube is open.
And then type c is the mountain peak but shifted over so the ear drum is moving but there is some pressure in there that isn't quite right.
Tympanometry tests how the eardrum and middle ear are working. This test is important because fluid or other problems in the middle ear can affect hearing. During tympanometry, a small earphone is placed in the ear canal. Air pressure is gently changed and the movement of the ear drum is measured. A tympanogram is a graph of the test results.
Tympanograms help identify the following:
- Fluid or pressure present in the middle ear
- Holes in the eardrum
- If ear tubes that have been placed in the ear are working correctly.
If the tympanogram is not normal, babies or young children may be referred to their doctor for medical treatment.
Diagnostic Otoacoustic Emissions (OAEs)
Diagnostic Otoacoustic Emissions (OAEs) are usually used with ABR and hearing test results.
- A small earphone is placed in the ear and tones are presented.
- The microphone measures an echo response from the inner ear in typical hearing ears. Ears with hearing loss may have a smaller echo than normal or no echo at all.
- This information helps determine if a hearing loss is present when the child cannot be tested using VRA or CPA.
