HOW DO I KNOW IF I HAVE A HEARING LOSS?
Hearing loss can be due to the aging process, exposure to loud noise, certain medications, infections, head or ear trauma, congenital (birth or prenatal) or hereditary factors, diseases, as well as a number of other causes. Recent data suggests there are over 34 million Americans with some degree of hearing loss. Hearing loss often occurs gradually throughout a lifetime. People with hearing loss compensate often without knowing they have hearing loss.
Common Signs of Hearing Loss Include:
- You hear people speaking but you have to strain to understand their words.
- You frequently ask people to repeat what they said.
- You don’t laugh at jokes because you miss too much of the story or the punch line.
- You frequently complain that people mumble.
- You need to ask others about the details of a meeting you just attended.
- You play the TV or radio louder than your friends, spouse and relatives.
- You cannot hear the doorbell or the telephone.
- You find that looking at people when they speak to you makes it easier to understand.
- You miss environmental sounds such as birds or leaves blowing.
If you have any of these symptoms, you should see a hearing professional to have an “audiometric evaluation.” An audiometric evaluation (AE) is the term used to describe a diagnostic hearing test, performed by a licensed hearing professional. An AE is not just pressing the button when you hear a “beep.” Rather, an audiometric evaluation allows the hearing professional to determine the type and degree of your hearing loss, and tells the professional how well or how poorly you understand speech. Speech understanding testing provides the professional with information about how successful amplification may be for your hearing loss.
The AE should also include a thorough case history (interview) as well as visual inspection of the ear canals and eardrum. Further tests of the middle ear function may also be performed. The results of the AE are useful to the physician should the hearing professional conclude that your hearing loss may be treated with medical or surgical alternatives. Results of the AE are plotted on a graph referred to as an audiogram. The audiogram provides a visual of your hearing test results across various frequencies.
TYPE AND DEGREE OF HEARING LOSS
Degrees of Hearing Loss
Results of the audiometric evaluation are plotted on a chart called an audiogram. Loudness is plotted from top to bottom; top of the graph is very quiet and bottom of the graph is very loud. Frequency, or pitch, from low to high, is plotted from left to right. Hearing loss (HL) is measured in decibels (dB) and is described in general categories. Hearing loss is not measured in percentages. The general hearing loss categories used by most hearing professionals are as follows:
- Normal hearing (0 to 25 dB HL)
- Mild hearing loss (26 to 40 dB HL)
- Moderate hearing loss (41 to 70 dB HL)
- Severe hearing loss (71 to 90 dB HL)
- Profound hearing loss (greater than 91 dB HL)
Types of Hearing Loss
The external and the middle ear conduct and transform sound; the inner ear receives it. When there is a problem in the external or middle ear, a conductive hearing impairment occurs. When the problem is in the inner ear, a sensorineural or hair cell loss is the result. When there are problems in the middle and inner ear, a mixed hearing impairment is the result (i.e. conductive and a sensorineural impairment). Central hearing loss has more to do with the brain than the ear, and will be discussed only briefly.
Conductive hearing loss occurs when sound is not conducted efficiently through the ear canal, eardrum, or tiny bones of the middle ear, resulting in a reduction of the loudness of sound that is heard. Conductive losses may result from earwax blocking the ear canal, fluid in the middle ear, middle ear infection, obstruction of the ear canal, perforation (hole) in the eardrum membrane, or disease of any of the three middle ear bones.
A person with a conductive hearing loss may notice that their ears may seem to be full or plugged. This person may speak softly because they hear their own voice quite loudly. Crunchy foods, such as celery or carrots, sound very loud and this person may have to stop chewing to hear what is being said. All conductive hearing losses should be evaluated by a physician to explore medical and surgical options.
Sensorineural hearing loss is the most common type of hearing loss. More than 90 percent of all hearing aid wearers have sensorineural hearing loss. The most common causes of sensorineural hearing loss are age related changes and noise exposure. A sensorineural hearing loss may also result from disturbance of inner ear circulation, increased inner ear fluid pressure, or from disturbances of nerve transmission. Sensorineural hearing loss is also called “cochlear loss,” an “inner ear loss” and “nerve loss.” Years ago, many professionals said there was nothing that could be done for sensorineural hearing loss – that is totally incorrect today. There are many excellent options for the patient with sensorineural hearing loss. A person with a sensorineural hearing loss may report that they can hear people talking, but they can’t understand what they are saying. An increase in the loudness of speech may only add to their confusion. This person will usually hear better in quiet places and may have difficulty understanding what is said over the telephone.
Central hearing impairment occurs when auditory centers located within the brain are affected by injury, disease, tumor, hereditary, or unknown causes. Loudness of sound is not necessarily affected, although speech understanding and clarity is affected. With this condition, a loss of loudness and clarity may occur at the same time.
