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ANN ARBOR,
MI - A baby wearing hearing aids? A toddler with a bionic ear
implant?
 It
might sound strange. But in fact, babies as young as seven weeks
can now get help from technology that helps them hear better. And
children whose hearing problems are discovered and treated early
go on to do much better at speaking, reading and learning than those
who are diagnosed later.
Severe hearing
loss in babies is more common than you might think, affecting one
or two infants in every thousand. It's actually one of the most
common birth defects.
That means
parents, hospitals and doctors should keep a careful watch for hearing
problems throughout a child's first years, says a University
of Michigan hearing expert. Just looking out for a few key signs
can make the difference.
"Hearing
is the learning channel," says Paul Kileny, Ph.D., director
of audiology for the U-M Health System. "It's very important
for all kinds of development and adjustment - not just academic,
not just speech and language, but also social development."
Kileny and his colleagues run one of the nation's oldest and most
comprehensive programs for detecting and treating early childhood
hearing loss.
Most hospitals
now test babies' hearing soon after birth, with one of several kinds
of high-tech machines. But many programs can't get to every baby,
and fewer hospitals make sure that infants who don't pass the first
test get an appointment for follow-up. Often, it's up to parents
to make sure their baby gets further testing and treatment.
The UMHS program,
which has screened 99 percent of babies born at or transferred to
the C.S. Mott Children's
Hospital in the past year, puts special emphasis on follow-up
care. The program makes sure that the vast majority of infants whose
screening test suggests a problem actually make it to a follow-up
test. Since last October alone, U-M audiologists have diagnosed
hearing loss in eight babies caught by the program.
Meanwhile,
parents whose babies "pass" the newborn test in the hospital
shouldn't get a false sense of security about their child's hearing,
Kileny warns.
"The newborn
test simply means that at that time, the baby most likely has normal
hearing," he says. "But it doesn't necessarily mean that
the same child later on, at six or eight months of age, can't necessarily
develop a hearing loss."
A number of
factors can lead to the development of a hearing loss that starts
weeks or months after birth. But, just like hearing loss in babies
who don't get screened shortly after birth, such problems often
go undetected because parents and health care providers don't pay
attention to clues that the baby isn't hearing well.
Some children
face special risks for a delayed-onset hearing loss - especially
those with a family history of childhood deafness. Half of all hearing
loss is genetic, and scientists at the U-M
Kresge Hearing Research Institute and other places are looking
for the specific genes involved.
Low-birthweight
and premature babies have extra risks of hearing loss, as do those
whose mothers had certain infections during pregnancy or difficulty
during delivery, and those treated with certain drugs or medical
techniques shortly after birth. UMHS has been testing nearly all
at-risk children born or treated at Mott and the Holden Neonatal
Intensive Care Unit since 1985.
But even children
with none of these risk factors can lose hearing in the first years
of life.
That's why
experts urge parents, caregivers such as day care providers, and
children's doctors to pay special attention to certain milestones
in their child's development. These clues can tell them if their
child's hearing is normal.
Some of this
monitoring should take place during well-baby doctor visits. Says
Kileny, "In the pediatrician's office, in the same way they
routinely test for motor skills just to determine that the infant
is developing normally, they should address the issues of hearing
development."
For children
with known hearing-loss risk factors, Kileny recommends formal hearing
testing between two and four months of age, and follow-up testing
every four to six months until the child reaches the age of two
or two and a half.
But between
visits, parents and caregivers should keep their guard up. They
should especially pay attention to a child's speech and language
development.
For instance,
a baby might begin to babble in his or her first few months, without
really monitoring those sounds with his or her own hearing. That
ability to connect sounds and hearing begins about halfway through
a child's first year. If a child stops babbling around six months
of age, Kileny says, that may signal a hearing loss.
During the
second half of a baby's first year, he or she should start to respond
to nearby sounds. "Most infants will start responding to their
name, and they will definitely pay attention and orient to familiar
voices such as that of a parent, a grandparent or a sibling,"
says Kileny. "They'll begin to utter one or even two words
by the end of the first year that should be reasonably intelligible."
In a child's
second year, the number of words in his or her vocabulary should
grow rapidly, and he or she should begin to form more and more complex
and multi-word sentences. If not, parents and health care providers
should consider the possibility of hearing loss and explore testing
and treatment options.
Many children
with hearing loss aren't diagnosed until this stage, because earlier
signs are missed. But by this time they've lost precious time in
developing their speech and language skills - possibly setting them
back on the road to learning and socializing.
Kileny urges
everyone who cares for a young child to trust their instincts about
possible hearing problems. "If there's concern by the parents,
some other caregiver or a health care provider, even though the
infant has passed the hearing screening early on, the child needs
to be referred for testing to confirm or rule out a hearing loss
that may have occurred later on in life."
He adds, "If
parents have the feeling that their concerns are not being responded
to adequately by their health care provider, they need to stand
up for their child and advocate for the child, to make sure that
these concerns are taken seriously and appropriate referrals are
made."
Depending on
the kind of hearing loss a child has, specialists may recommend
hearing aids or even a cochlear
implant - a "bionic ear" that sends sounds directly
to the brain. The U-M has a special support program for the parents
of children with newly diagnosed hearing loss.
Hearing aid
specialists at UMHS have developed techniques to fit and test hearing
aids for babies as young as seven or eight weeks. The aids amplify
sounds coming into the ear, helping overcome diminished hearing
caused by certain factors. Children can receive new hearing aids
as they grow, and as their hearing and technology changes.
For children
with more severe hearing loss, cochlear implants offer a way to
hear speech and sounds. The device gathers sound using a device
behind the ear, then uses a computer processor to turn them into
impulses that are fed to a nerve that connects to the brain.
UMHS has been
implanting the devices in children for more than a decade, and has
built one of the most experienced teams and one of the largest programs
in the world. Children as young as one year have received a cochlear
implant at the U-M.
No matter what
parents choose for their child, Kileny emphasizes, "Early intervention
is extremely important in infants and young children with hearing
loss, in order to attempt to maintain the normal pace of speech,
language and intellectual development."
Listening
& speech milestones in children:
(If a child does not reach these, a hearing test is recommended.)
- At birth,
babies should awaken or startle to loud sounds, make pleasurable
sounds and respond or hush to a caregiver's voice.
- By three
months, babies will watch a speaking parent's face, smile when
spoken to, and repeat cooing sounds.
- From 4 to
6 months, infants will respond to changes in a parent's tone of
voice, look for the source of sounds like dogs barking or doorbells
ringing, and babble or use simple sounds.
- From 7 to
12 months, toddlers will begin to recognize words for common items,
enjoy games like peek-a-boo, and begin to make speech sounds and
use one or two words.
- From 1 to
2 years, a child will point to objects by name, follow simple
commands like "roll the ball", begin to ask simple questions
and use more words each month.
- From 2 to
3 years, children understand differences like "in and out",
follow two-part requests like "get the ball and put it on
the table," can name most objects and use short sentences.
Risk factors
for hearing loss:
- Family history
of childhood hearing loss
- Infections
the mother had during pregnancy, such as syphilis, herpes and
rubella
- Bacterial
meningitis
- Misshapen
ears, and ear "tags" or "pits", or cleft palate
- Serious
infection or illness needing treatment in a neonatal intensive
care unit
- Head injury
with a skull fracture or loss of consciousness
- Repeated
or long-term presence of fluid in the eardrum for at least three
months
Learn more
on the World Wide Web or by phone:
U-M Early Childhood Hearing Program: www.med.umich.edu/childhearinginfo
or 734-764-3486
American Speech-Language-Hearing Association: Hearing loss in children
www.asha.org/hearing/disorders/children.cfm
or 800-638-8255
National Institute on Deafness and Other Communication Disorders:
Information for parents
www.nidcd.nih.gov/health/parents/commopt.htm
or 800-241-1044 [TTY: (800) 241-1055]
Written
by: Kara Gavin
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