HEARING IMPAIRMENT OR LOSS (Deafness)

General Information

DEFINITION--

Decreased ability or complete inability to hear. Classifications include:

• Conductive loss, in which mechanical problems keep the sound from reaching the middle ear.
• Sensorineural loss, in which the 8th cranial nerve (the acoustic nerve) is damaged--often due to excess noise over a period of time.
• Mixed loss, involving both conductive and sensorineural disabilities.

BODY PARTS INVOLVED--Middle-ear bones that conduct sound; branches of the 8th cranial nerve that transmit sound to the brain.

SEX OR AGE MOST AFFECTED--Both sexes; all ages.

> Lack of response to environmental sounds--

especially startling sounds.

• Older infant (5-10 months) doesn't turn head to side where sound originates. In older persons:
• Difficulty in discriminating (listening selectively) to environmental sounds.
• Ringing in the ears, dizziness, pain.
• Turning up the volume of the radio or TV.
• Frequently asking people to repeat speech.

CAUSES

• Impacted earwax or fluid behind the eardrum.
• Congenital, transmitted as a dominant or recessive genetic trait.
• Chronic middle-ear infections or spread of infection to the inner ear.
• Blood-vessel disorders, including hypertension.
• Head injury or other trauma; brain tumor.
• Blood clot that travels to the acoustic nerve.
• Multiple sclerosis.
• Blood-coagulation disorders.
• Pressure changes due to flying or diving.
• Prolonged exposure to sound levels of 85 decibels or above.
• Aging. Most persons over 65 have some hearing loss of high-pitched tones.

RISK INCREASES WITH

• Family history of congenital or acquired deafness.
• Use of drugs, such as nonsteroidal anti-inflammatories, cisplatin, erythromycins, gentamycin, streptomycin, tobramycin, quinine, furosemide, ethacrynic acid or heavy doses of aspirin and others.
• Persons with occupations or hobbies involving high noise levels.

HOW TO PREVENT

• Avoid prolonged use or overdosage of drugs that cause hearing loss.
• Obtain medical treatment for underlying disorders that cause hearing loss, particularly ear infections, allergic and respiratory problems.
• Avoid prolonged exposure to loud noise. If exposure is unavoidable, protect your ears with ear plugs or ear muffs.

What To Expect

DIAGNOSTIC MEASURES--

• Medical history and exam by a doctor.
• Audiometry (test of hearing ability) and hearing tests performed with a tuning fork (Rinne test) will be used to diagnose hearing disorders.

APPROPRIATE HEALTH CARE

• Doctor's treatment.
• Earwax removal or eardrum puncture repair may resolve hearing problem.
• If related to medications, changes in dosage or discontinuation may help.
• Treatment for other underlying causes.
• Surgery for conductive-type deafness (sometimes).
• Speech therapy and rehabilitation, if needed.

POSSIBLE COMPLICATIONS

• Permanent deafness.
• Delayed language development in a child.
• Emotional impact of deafness.

PROBABLE OUTCOME--Some conductive hearing loss is curable with surgery. Hearing loss caused by prolonged exposure to loud noise sometimes disappears when the noise is eliminated. Other types of hearing loss are usually permanent.

How To Treat

GENERAL MEASURES--

• If hearing loss is permanent and disabling: Learn sign-language and lip-reading skills. Wear a hearing aid, if one is prescribed. Speech therapy and rehabilitation, if needed. Special phone equipment is available. Resist the temptation to withdraw socially because of your hearing difficulty. Isolation will increase your communication problems and frustration, and make adjustment more difficult.
• See Resources for Additional Information.

MEDICATION--Medicine usually is not needed.

ACTIVITY--No restrictions.

DIET--No special diet.

Call Your Doctor If

• Your child shows signs of hearing impairment.
• You suspect you have a hearing loss.