Hearing Impairment in Children
(See also Hearing Loss.)
Hearing loss usually results from genetic defects in newborns and from ear infections or earwax in older children.
If children do not respond to sounds, have difficulty talking, or are slow starting to talk, their hearing may be impaired.
A handheld device or a test that measures the brain’s responses to sounds is used to test hearing in newborns, and various techniques are used for older children.
If possible, the cause is treated, but hearing aids are usually needed.
If hearing aids are not effective, a cochlear implant can sometimes be helpful.
Hearing impairment is relatively common among children. About 1.9% of children have trouble hearing, and permanent hearing loss is found in more than 1 out of every 1000 children screened for hearing loss, whether or not they have symptoms.
Hearing impairment is slightly more common among boys. Not recognizing and treating impairment can seriously impair a child’s ability to speak and understand language. The impairment can lead to failure in school, teasing by peers, social isolation, and emotional difficulties.
Genetic defects are the most common cause of hearing impairment in newborns.
Ear infections, including secretory otitis media, and accumulation of earwax are the most common causes of hearing impairment in infants and older children. In older children, other causes include head injury, loud noise (including loud music), use of certain drugs (such as aminoglycoside antibiotics or thiazide diuretics), certain viral infections (such as mumps), tumors, injury by pencils or other foreign objects that become stuck deep in the ear, and, rarely, autoimmune disorders.
Parents may suspect severe hearing impairment if the child does not respond to sounds or if the child has difficulty talking or delayed speech.
Less severe hearing impairment can be more subtle and lead to behavior that is misinterpreted by parents and doctors, such as the following:
In general, if children are developing well in one setting but have noticeable social, behavioral, language, or learning difficulties in a different setting, they should be screened for hearing impairment.
Because hearing plays such an important role in a child’s development, many doctors recommend that all newborns be tested for hearing impairment by the age of 3 months. This testing is required by law in many states.
Most states require that newborns undergo routine screening tests to detect hearing impairment. Newborns are usually screened in two stages. First, newborns are tested for echoes produced by healthy ears in response to soft clicks made by a handheld device (evoked otoacoustic emissions testing). If this test raises questions about a newborn’s hearing, a second test is done to measure electrical signals from the brain in response to sounds (the auditory brain stem response test, or ABR). The ABR is painless and usually done while newborns are sleeping. It can be used in children of any age. If results of the ABR are abnormal, the test is repeated in 1 month. If hearing loss is still detected, children may be fitted with hearing aids and may benefit from placement in an educational setting responsive to children with impaired hearing.
In older children, several techniques are used to diagnose hearing impairment:
Asking a series of questions to detect delays in a child’s normal development or to assess a parent’s concern about language and speech development
Examining the ears for abnormalities
For children aged 6 months to 2 years, testing their response to various sounds
Testing the response of the eardrum to a range of sound frequencies (tympanometry), which may indicate whether there is fluid in the middle ear
After age 2 years, asking children to follow simple commands, which usually indicates whether they hear and understand speech, or testing their responses to sounds using earphones
Treating some reversible causes of hearing loss can restore hearing. For example, ear infections can be treated with antibiotics or surgery, earwax can be manually removed or dissolved with ear drops, and cholesteatomas can be surgically removed.
Most often the cause of a child’s hearing loss cannot be reversed, and treatment involves use of a hearing aid to compensate for the impairment as much as possible.
Hearing aids are available for infants as well as older children. If hearing loss is mild or moderate or affects only one ear, a hearing aid or earphones can be used. Children who have hearing impairment in only one ear can be helped by using an FM auditory trainer that transmits a teacher’s voice to a hearing aid in the normal ear.
Hearing Aids: Amplifying the Sound
Cochlear implants (a surgically implanted system that sends electrical signals directly into the auditory nerve in response to sounds) may be used for children whose hearing loss is severe enough that it cannot be managed with hearing aids.
Children may also require therapy to support their language development, such as being taught a visually based sign language.
People in deaf communities are proud of their rich culture and alternative forms of communication. Many deaf people oppose surgery for the treatment of severe hearing impairment on the grounds that it may deny children membership in the deaf community. Families who wish to consider this approach should discuss it with their doctor.