Hearing Loss

What is hearing loss?

A hearing impairment refers to all degrees of hearing loss. Types of hearing loss are classified by where in the ear the problem occurs and the severity of loss.

What are the types of hearing loss?

A conductive hearing loss results when something interferes with sound waves traveling through the outer and middle parts of the ear. Causes of conductive hearing loss include:

Conductive hearing losses may or may not be permanent depending on the cause.

A sensorineural hearing loss results from a problem in the innermost part of the ear or in the auditory nerve (the term auditory refers to hearing). Causes of sensorineural hearing loss include:

Sensorineural hearing losses are permanent. Sometimes the problem with the inner ear also causes problems with balance. Children with both hearing and balance problems may have mild delays in the development of their motor skills.

A child may have both a sensorineural hearing loss and a conductive hearing loss. This type of hearing loss is called a mixed loss.

What are the levels of severity?

Hearing losses are also classified by their severity: mild, moderate, severe, and profound. The level of severity is determined by the loudness of sound that a child can hear without a hearing aid. The loudness of sound is measured in decibels (dB).

Mild : Children with mild hearing losses can hear sounds of 20 to 40 dB or louder. They may have trouble hearing faint or distant speech. The most common cause of a mild hearing loss is fluid collection in the middle ear, a conductive hearing loss.

Moderate : Children who have moderate losses of hearing can hear sounds louder than 45 to 60 dB. They need speech to be loud. It is hard for these children to understand speech in group situations.

Severe : Children with severe losses can hear sounds of 65 to 85 dB or louder. They can hear only loud voices one foot or less away, or loud sounds in the environment.

Profound : Children with profound hearing losses may hear loud sounds of 90 dB or more, but they may be more aware of vibrations than sound. The term deaf usually applies to children with profound hearing losses or to children with no hearing at all.

Children with hearing loss that crosses two levels of severity are given the label of both; for example, mild to moderate hearing loss, or moderate to severe.

How and when should my child be tested?

Early testing is important in helping a hearing-impaired child adapt to the hearing world. Every child who may have a hearing loss needs thorough testing of his hearing and middle ear function. A child is never too young to have a hearing test.

An audiologist performs hearing tests. He or she is specially trained to recognize and evaluate hearing. If necessary, an audiologist can fit your child with a hearing aid.

After a hearing loss is diagnosed, health care professionals will try to find out the cause of the hearing loss. They will also look for related problems or disabilities. Additional tests may include blood tests, an EKG, and a CAT scan (a special x-ray) of the middle and inner ear. It is important to try to find out if the cause, especially if it is a genetic cause. Then you will know if your next child has a chance of having the same problem.

Results from these tests help determine the best treatment and educational strategy for your child. Tests can be taken in a special center for assessing disabled children, or by a team of professionals your pediatrician selects. The professionals may include an otolaryngologist (a doctor who specializes in the ear, nose, and throat problems), an ophthalmologist (an eye doctor), a developmental pediatrician, a geneticist, a speech/language pathologist, a psychologist, and a learning specialist.

Hearing-impaired children need regular hearing, ear, and eye exams. Typically, audiologists see younger children more frequently than older children because their ear canals are growing and changing shape. Young children may often need new ear molds for holding the hearing aid in place. Because your child's primary way of learning and communicating is through sight, regular eye exams are important to make sure there are no problems.

Call your child's doctor if there is any sudden change in your child's response to sound, especially from a cold. The change may signal a middle ear problem. A buildup of fluid in the middle ear could worsen your child's hearing loss. Most doctors put ventilating tubes (ear tubes) in children who have a sensorineural hearing loss and fluid in the middle ear. Any additional hearing loss may make a big difference in what a child can hear. A child with ear tubes can continue to use hearing aids.

What is the treatment?

A child's early years are very important for learning and the development of language. Treating hearing impairment early makes a big difference in how well a child functions later in life. The audiologist tries to provide the best use of a child's remaining hearing. She or he designs a treatment plan for your child. This plan consists not only of making sound louder with hearing aids, but also hearing and language training, and parent support and training.

Hearing aids do not restore hearing. They are loudspeakers that help get the best sound possible to your child's ear. The aid makes sounds louder, not clearer. It may distort some sounds.

A very important aspect of treatment is teaching your child how to hear better; for example, by ignoring noises in the environment and paying attention to voices. Make sure that you talk to the audiologist about what sounds your child can hear with and without a hearing aid, the effects of noise on your child's hearing, and how to keep the hearing aids in the best working order.

Children of all ages can use hearing aids. The aids even help young infants.

The cochlea is the part of the ear that turns the vibrations we call sound into electrical signals. The brain then interprets the signals into meaningful sounds such as speech. Some children with hearing loss may benefit from an electronic device called a cochlear implant (CI).

A CI consists of three parts: a microphone, a microcomputer, and a cochlear electrode. The microphone, worn behind the ear, sends the sound to a microcomputer. The microcomputer is connected to the microphone by a wire and is worn in a pouch attached to the belt. It turns the sound into an electrical code which is sent by radio wave to the cochlear electrode. The wire electrode is surgically implanted through the skull behind the ear into the cochlea. The cochlear implant does not give the child normal hearing. However, the child may be able to interpret the signals produced by the implant after he or she gets used to the signals and what they mean.

Children as young as 12 months may be able to have a cochlear implant. The cost of the implant ranges between $20,000 to $25,000. The surgery and language training costs another $15,000 to $20,000. There is only a 1% failure rate and a 2% to 3% chance of complications from surgery.

The results of an implant may vary from child to child. Most all children who get an implant have improved hearing and oral language abilities. How much your child improves will depend on the therapies given after surgery, not on the type of device that was implanted.

Cochlear implants were once only used in children with profound hearing loss. Now, they are being used for children with less severe hearing loss as well. Your team of doctors and hearing specialists will help you decide if an implant is right for your child. After the implant is put in, your child will need to have intensive language training and will still need the therapies listed below.

Language training programs for hearing-impaired children are offered as early as infancy. Parent-infant programs help parents provide an environment rich in language for their child.

Hearing-impaired children use a variety of ways to communicate. You will need to decide which way works best with your child.

Auditory oral approach: The auditory oral approach trains children to make the most of their speech and hearing abilities. It works best with children who have a lot of hearing left.

Total communication: The total communication approach uses speech, hearing, vision, speech-reading, finger spelling, reading, writing, and signing (American Sign Language).

The best approach for a child depends on such factors as:

Think about and discuss the following questions to help determine the best method of communication for your child:

Contact your local school district before your child starts school. Children with hearing loss usually require some special classroom changes. A team of professionals will help evaluate your child and put together an Individual Education Plan (IEP). Parents have a right to help put together this plan. You may also ask your doctor to review the plan. In some schools there are programs available for children with hearing loss. Ask and find out all the services that may be available for your child.

How can I help my child learn to communicate?