Published: Oct. 17, 2006
Updated: Apr. 20, 2010
Two-and-a-half-year-old Nina was bright-eyed and bouncy, full of laughter and hugs -- when you could get her attention. She often seemed to be ignoring her parents when they spoke to her, and when she did respond, many of her words were slurred.
Concerned, her parents arranged for a hearing test -- and learned that Nina had moderate hearing loss in both ears. Outfitted with a hearing aid, and provided with speech therapy, she is just beginning to regain some of the ground she lost during the first years of life when important language skills are being learned.
"Hearing impairment is the largest congenital disability, affecting about six out of every 1,000 infants," says Duke pediatric audiologist Ann Mabie. "For a very long time, people thought you couldn't test infants' hearing, and would just wait until children were two or three years old. But by the time you wait for children not to talk, a window of opportunity has shut."
In fact, those tiny, shell-like ears that parents marvel over when getting to know their new babies are just the most visible parts of a highly sophisticated machine. Human infants spend the first year of life learning about their environment, and by one year of age, already understand far more language than they are yet able to use -- unless an undiagnosed hearing impairment disrupts the process.
While hearing impairments are difficult at any age, they’re especially devastating in young children, because their brains rely on auditory stimulation to develop the capacity for oral communication. This makes early diagnosis and treatment of childhood hearing losses essential.
Happily, all newborns in North Carolina now have access to the specialized screening needed to diagnose infants with hearing loss, thanks to state legislation passed in October 1999.
Even babies born with normal hearing, however, can develop a hearing loss later in infancy or childhood, due to ear infections or head injuries. So parents should be aware of clues that their children might have difficulty hearing and insist on tests if they suspect hearing loss (see below).
Mabie urges all parents who suspect that their child might have a hearing problem to get the child tested by an audiologist or physician with expertise in this area as soon as possible: "Every day you wait is a day lost."
Hearing impairments caused by problems in the middle and outer ear can sometimes be treated medically. For impairments originating in the inner ear, a hearing aid and speech therapy can help. "Hearing aids help provide access to speech, and with some intensive speech and language therapy, hearing-impaired kids will do fine in a normal classroom."
Children with severe to profound hearing impairments typically will require more extensive rehabilitation, and cochlear implantation may be indicated. At Duke, otolaryngologists have begun using sophisticated new technologies to help even tiny children with hearing impairments to interact with the hearing world.
When Lauren, a two-month-old infant from western North Carolina, was diagnosed with profound hearing loss due to a malformation in her inner ears, or cochleas, she was immediately fitted with hearing aids. Shortly before her second birthday, she came to Duke for a cochlear implant.
Duke specialists in speech pathology and audiology worked to perform a detailed evaluation of Lauren’s hearing loss, using the most precise diagnostic technologies available. Duke neurotologist (ear specialist) Debara Tucci, MD, then selected the cochlear implant that would be most appropriate for Lauren.
After Tucci surgically implanted the mechanism -- a marvel of micro-engineering -- into Lauren’s inner ear, the tiny computer chip that controls the implant was carefully adjusted to transmit just the right auditory signals to Lauren’s brain. The result is a girl who is learning how to communicate with those around her right on schedule.
Whatever intervention a child with hearing deficiencies may need, time is of the essence. As the mother of one hearing-impaired child puts it, "Once you find out and take action, things only get better, not worse.”
If your child exhibits any of the following behaviors, have him or her checked by a professional audiologist or physician with expertise in hearing disorders.