Hearing Tests

There is a strong relationship between age and reported hearing loss: 18 percent of American adults 45-64 years old, 30 percent of adults 65-74 years old, and 47 percent of adults 75 years old or older have a hearing loss.

Approximately 15 percent (26 million) of Americans between the ages of 20 and 69 have high frequency hearing loss due to exposure to loud sounds or noise at work or in leisure activities.

Approximately 4,000 new cases of sudden deafness occur each year in the United States. Hearing loss affects only 1 ear in 9 out of 10 people who experience sudden deafness. Only 10 to 15 percent of patients with sudden deafness know what caused their loss.

Of adults ages 65 and older in the United States, 12.3 percent of men and nearly 14 percent of women are affected by tinnitus. Tinnitus is identified more frequently in white individuals and the prevalence of tinnitus is almost twice as frequent in the South as in the Northeast.

Types of Hearing Loss

There are four commonly recognized different types of hearing loss:

• Conductive
• Sensorineural
• Mixed
• Central

Conductive Hearing Loss

A conductive hearing loss occurs when sound is not conducted efficiently through the ear canal, eardrum, or through the tiny bones of the middle ear.  This results in a reduction of the loudness of a sound. Common causes of a conductive hearing loss include:

• Trauma to the ear
• Fluid in the middle ear
• Excessive wax in the outer ear canal
• Outer ear infection

Sensorineural Hearing Loss

Often referred to (in error) as “nerve deafness” a sensorineural hearing loss is caused by damage to the hair cells in the cochlea. These cells cannot be repaired or replaced. Common causes of sensorineural hearing loss include:

• Exposure to loud noises
• The aging process
• Viral Infections
• Trauma to the ear
• Medications that are toxic to the ear

Typically a sensorineural hearing loss is permanent and irreversible.  The only solution for most people with a sensorineural hearing loss to improve their ability to hear is to use hearing aids.

Mixed Hearing Loss

Some people have both a conductive and a sensorineural hearing loss.  A combination of the two different types is referred to as a mixed hearing loss. For example, a mixed loss can occur when someone has a sensorineural hearing loss and develops fluid in their middle ear causing a conductive hearing loss. They may notice a decline in their ability to hear as a result of the temporary change in their hearing caused by the conductive hearing loss.  Once the conductive hearing loss is resolved, their hearing levels should return to the level it was prior to the conductive hearing loss.

Central Hearing Loss

Our outer and inner ears allow us to “hear” sound, but the brain, allows us to “understand” sound.  Various medical issues can cause our processing of auditory stimuli to breakdown causing a central hearing loss also known as an auditory processing disorder. Persons with a central hearing loss can hear sound but have difficulty with understanding or processing what they heard. When a central hearing loss is suspected, there are tests that can be done to determine if a hearing loss is due to a central auditory processing problem.