The ears are sensitive sensory organs of the body that are susceptible to damage, including hearing impairment or loss.

The National Institute on Deafness and Other Communication Disorders says approximately 15 percent of the U.S. population between the ages of 20 and 69 has high frequency hearing loss due to exposure to loud sounds or noise from work and leisure activities. School-aged children and even babies can have varying stages of hearing loss. Such loss might have been present at birth, but it also can be a byproduct of environmental factors.

Anyone can experience hearing loss and at varying degrees. Medical professionals distinguish different levels of hearing loss as mild, moderate, severe, and profound. Deafness can be categorized in two main types: conductive and sensory-neural.

Conductive hearing loss is sound blocked from reaching the inner ear. Sensory-neural hearing loss stems from impairment of sensory cells inside of the ear or neurological impairment that compromises reception of sound or understanding of language.

Tests will determine the type and severity of hearing loss. The American Hearing Research Foundation identifies six types of hearing tests.

Bedside testing

A doctor may use some sort of common sound, such as whispering, snapping, or a ticking watch, to quantify a patient's ability to hear sounds. He or she also may use tuning forks to test at chosen frequencies.
Audiometry. This test is conducted using an audiometer that gives off a variety of pitches. When higher levels of decibels are needed, this indicates hearing impairment.

Tympanometry

This is a measure of the stiffness of the eardrum to evaluate middle ear function. Tympanometry can identify fluid in the middle ear, perforations and abnormal middle ear pressure.

Brainstem auditory evoked responses

Often referred to as a BAER test, this measures the timing of electrical waves from the brainstem in response to clicks sounded at the ear.

Electrocochleography. This test is a variant of the BAER and uses an electrode placed on or in the eardrum to amplify sound waves.

Otoacoustic emission

This procedure is used to assess hearing loss in newborns and verify if the cochlea (spiral-shaped hearing organ inside of the inner ear) is working correctly. A small probe is inserted into the ear and quiet tones are sent to simulate movement of the hairs on the cochlea.

Often it is up to parents, spouses and caregivers to recognize the signs of hearing loss and suggest testing. Some signs of hearing loss are more noticeable. Here are some indicators.

* Asking people to repeat themselves

* Turning up the radio or television volume to a level that is loud for others

* Difficulty hearing on a telephone

* Difficulty hearing when women or children speak

* Problems following a fast-moving conversation

* Feeling like others are always mumbling

* Difficulty making out conversations in noisy places

If you have repeatedly experienced any of these signs, the American Speech-Language-Hearing Association suggests scheduling an appointment with your doctor. He or she can determine if an appointment with a certified audiologist is necessary.

By MS