Q: When should an infant
be screened for hearing loss?
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All infants should be screened for hearing loss
before 1 month of age, preferably before leaving the birth hospital. The
age of a child when a hearing loss is diagnosed is important to the
development of the child’s speech, language, cognitive, and psychosocial
abilities.
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Without universal screening by 1 month, the average
age at which hearing loss is identified in children is 2 to 3 years old.
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Newborn hearing screening costs about $30 per child
and takes about 9 minutes to do. Costs are much higher if a hearing loss
is not diagnosed until later in life. In the 1995-1996 school year, the
total U.S. costs for special education programs for children with hearing
loss exceeded $375 million.
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Infants with risk indicators for progressive or
delayed-onset hearing loss should receive audiologic monitoring every 6
months until age 3 years
(JCIH Year 2000 Position Statement); Note: This statement is available
from the American Academy of Pediatrics (AAP) website:
www.aap.org
-
Find out what Screening Guidelines are recommended by
various organizations.
[Return to FAQs]
Q: What happens if an infant
does not pass the hearing screening?
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All infants who do not pass the hearing screening
should be referred for further testing to rule out or confirm a
hearing loss.
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All infants with confirmed hearing loss should be
referred for a comprehensive medical evaluation to assess the causes and
look for potential or related disabilities.
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Depending on the results of the audiological and
medical examinations, infants may be referred to an intervention program.
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To find out more about intervention options, please
contact CDC Info at (800) 232-4636 or
cdcinfo@cdc.gov
To learn more about infant hearing loss and how the
ear works you can visit the Boys Town National Research Hospital
babyhearing.org website.
[Return to FAQs]
Q: How can I find resources
such as hearing screening tests that are available in my area?
To learn more about programs and services in your
area, please contact your local Early Hearing Detection Intervention (EHDI)
Program coordinator. You will find this information by going to our
website at:
http://www.cdc.gov/ncbddd/ehdi/documents/stateHL_contacts.pdf
[Return to FAQs]
Q: What does it mean to have
a false positive newborn hearing screening test?
A false positive hearing screening test result is
when a baby does not have a hearing loss but the newborn does not pass
the hearing screening. Hearing screening tests are not meant to diagnose
hearing loss in infants. Instead, they are meant to find all infants that
might have a hearing loss. Because they are not a diagnostic test,
hearing screening tests sometimes misidentify infants as having a hearing
loss.
If a baby does not pass the newborn hearing screening
test, it is VERY important to make sure the baby gets follow-up testing
to be SURE that the baby does not have a hearing loss.
In the United States, between 10 and100 babies per
1,000 (1 to 10 percent) do not pass the screening test. Only one to
three babies per 1,000 (less than 1 percent) actually have hearing loss.
This means that most of the babies referred for diagnostic testing will
be shown to have no hearing loss.
[Return to FAQs]
Q: Why don’t all
infants have a diagnostic test for hearing loss?
A diagnostic test takes a long time, it cannot be
done before a baby goes home from the birth hospital, and it is
expensive. A hearing screening test is quick, it can be done before a
baby leaves the birth hospital, and it is relatively inexpensive.
Screening tests are common in medicine. Checking your
vision with an eye chart in the doctor’s office is a screening test. Just
because you have trouble reading the eye chart does not necessarily mean
that you need glasses. More testing is usually done by a special doctor –
an eye doctor. In the same way, if a baby does not pass the hearing
screening test, more testing is done by a specialist called an
audiologist.
If a baby does not pass the newborn hearing screening
test, it is VERY important to make sure the baby gets a follow-up
diagnostic test. To be SURE that the baby does not have a hearing loss
For more information, please see
http://www.babyhearing.org/HearingAmplification/
NewbornScreening/index.asp
http://www.asha.org/public/hearing/testing
http://www.aap.org/policy/re9846.html
http://www.nidcd.nih.gov/health/hearing/
baby_screening.asp
[Return to FAQs]
Q: What is an Auditory
Brainstem Response (ABR) test?
Auditory (hearing) Brainstem Response - a test that
checks the brain's response to sound and is measured by placing
electrodes (non-invasive) on the head to record the brain’s response to
sound.
http://www.babyhearing.org/hearingamplification/
glossary/index.asp#ABR
[Return to FAQs]
Q: What is an Otoacoustic
Emissions (OAE)?
Otoacoustic Emissions – is a test that checks the
inner ear response to sound and is measured by placing a very sensitive
microphone in the ear canal to measure the ear’s response to sound.
http://www.babyhearing.org/hearingamplification/
glossary/index.asp#OAE
Additional information may be found at:
http://www.asha.org/public/hearing/testing
[Return to FAQs]
Q: What is the
difference between Auditory Brainstem Response testing and Behavioral
Audiometry Evaluation?
To understand the difference between Auditory
Brainstem Response (ABR) testing and Behavioral Audiometry Evaluation
(please see below for an explanation), it is important to understand a
little about how the ear works.
The ear has three main parts: the outer ear, the
middle ear, and the inner ear.
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The outer ear includes the visible portion of the ear
and the ear canal. Sound waves travel through these two areas of the
outer ear.
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The middle ear includes the eardrum (the tympanic
membrane) and three small bones (ossicles). The movement of the tympanic
membrane makes the ossicles vibrate.
-
The inner ear includes a snail-shaped fluid-filled
cochlea, which contains thousands of sound receptors (hair cells). The
inner ear is responsible for changing the sound vibrations into
electrical signals. The electrical signals are picked up by the hearing
(acoustic) nerve. The acoustic nerve sends the sound to the brain.
When an adult or child has a hearing loss, one or
more of these parts are not working in the usual way. In order to fully
test hearing, all parts of the ear, the acoustic nerve, and the brain
pathways that are involved in hearing must be tested for proper
functioning.
Auditory Brainstem Response (ABR) testing
focuses only on the function of the inner ear, the acoustic nerve, and
the brain pathways that are associated with hearing. This test is used
for babies, children, and adults. For this test, electrodes are placed on
the individual’s head (similar to electrodes placed around the heart when
an electrocardiogram is done), and brain wave activity in response to
sound is recorded. Because this test does not rely on behavior, the adult
or child being tested can be sound asleep during the test.
Behavioral Audiometry Evaluation tests the
function of all parts of the ear, including the acoustic nerve and the
brain pathways involved in hearing. Infants and toddlers are observed for
changes in their behavior such as sucking a pacifier, quieting, or
searching for the sound. They are rewarded for the correct response by
getting to watch an animated toy (this is called visual reinforcement
audiometry). Sometimes older children are given a more play-like activity
(this is called conditioned play audiometry). The child being tested must
be awake and cooperative during this test.
Q: Why is more than one
hearing screening test necessary?
Hearing loss in an infant or child cannot be
confirmed with one test alone. Several tests must be done to check
different parts and different functions of the ear. Audiologists refer to
a group of tests as a “battery of tests”. Because Behavioral Audiometry
Evaluation tests the function of all parts of the ear, it is considered
fundamental to the battery of tests used to evaluate older infants and
children for hearing loss. However, because this test relies on behavior
and the cooperation of the infant, it is not reliable until the child
reaches the developmental age, of 5 to 6 months. For children younger
than 5 to 6 months of age and for children who are developmentally
delayed, ABR testing is considered the most important of these tests.
[Return to FAQs]
Sorry, we can't give you medical advice. Please talk
with your doctor for questions about yourself or your family. For other
information, please contact ehdi@cdc.gov
[Return
to Top]
Date: September 1, 2006
Content source: National Center on Birth Defects and Developmental
Disabilities
