Hearing Loss
Definition
- Conductive hearing loss due to something interfering with the sound passing to the inner ear.
-
Sensorineural hearing loss due to damage to:
- The major organ in the ear responsible for hearing (the cochlea)
- The major nerve pathway (8th cranial nerve) and/or area of the brain responsible for hearing
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Causes
- Impacted ear wax
- Fluid in the middle ear
- Ear infections
- Perforation of ear drum
- Stiff bones in the middle ear (otosclerosis)
- Injury
- Loose or fractured bones in the middle ear
- Missing bones from the middle ear due to previous surgery
- Congenital anomaly causing complete closure of the ear canal (atresia)
- Tumors
- Excess noise
- Aging
- Family history
-
Exposure to toxic substances, including such drugs as:
- Streptomycin
- Gentamicin
- Chemotherapy drugs
- Diuretics
- Steroids
- Heart medicines
- Anesthetics
- Quinine
- Aspirin-containing drugs
- Acoustic neuroma
- Cardiovascular disease
- Multiple sclerosis
- Viruses ( measles, mumps, adenovirus, rubella)
- History of meningitis or syphilis
- Neurologic diseases such as multiple sclerosis and stroke
- Inner ear disorders such as Meniere’s disease
- Otosclerosis affecting the inner ear
- Previous brain or ear surgery causing damage to the inner ear
- Trauma
Risk Factors
- Family history
- Aging
- Meniere's disease
- Not receiving all recommended immunizations
- Repeated or poorly treated ear infections
- Exposure to loud noise, music, or machinery
- Use of certain antibiotics and chemotherapy drugs
- Diseases that may result in blocked blood flow, including atherosclerosis, problems with blood clots, and collagen vascular diseases
Symptoms
-
Decreased ability to hear any of the following:
- Higher pitched sounds
- Lower pitched sounds
- All sounds
- Speech when there is background noise
- Dizziness
- Ringing sounds in the ears
- Problems with balance
- In children, hearing loss may cause difficulty learning to speak.
When Should I Call My Doctor?
- Ear pain
- Dizziness
- Ringing or other sounds in your ear
- Problems with speech or balance
- Sensitivity to sound
Diagnosis
- Weber test—a tuning fork sounded and placed on your forehead or teeth. This can help distinguish conductive from sensorineural hearing loss.
- Rinne test—a tuning fork sounded and placed in front and then behind of the ear. This can help distinguish conductive from sensorineural hearing loss.
- Audiometric tests—These involve listening to tones in a soundproof room and reporting whether or not you hear the tones.
- Tympanometry—This test measures the pressure in the middle ear and examines the middle ear's response to pressure waves.
- Computed tomography (CT) or magnetic resonance imaging (MRI) scan of the head—a type of imaging study that uses a computer to make pictures of the inside of the head. This may be done to check for a tumor or bone injury.
- Brain stem auditory evoked responses—electrodes attached to the scalp and used to measure the electrical response of the brain to sound
- Electrocochleography—This tests the cochlea and the auditory nerve.
Treatment
Earwax Removal
Hearing Aids
Devices
Treat Other Medical Illnesses
Discontinue or Change Medications
Address Nutritional Deficiencies
Surgery
Home Care
- Face the person that you are talking to. This will allow you to see their facial expressions and watch their lips move.
- Ask other people to speak loudly and more clearly.
- Turn off background noise (eg, TV, radio).
- In public places, choose a place to sit that is away from noise.
- Work with a special trainer to learn how to lip read. Lip reading involves paying close attention to how a person’s mouth and body are moving when they talk.
Prevention
- Stop smoking.
- Adequately treat ear infections.
- Get all appropriate immunizations.
- Treat all medical conditions.
- Avoid exposure to excess noise.
- Use adequate ear protection when using noisy equipment.
RESOURCES
American Academy of Otolaryngology–Head and Neck Surgery, Inc. http://www.entnet.org/
American Speech-Language-Hearing Association http://www.asha.org/
CANADIAN RESOURCES
Health Canada http://www.hc-sc.gc.ca/
Society of Rural Physicians of Canada http://www.srpc.ca/
References
Ferri FF. Ferri's Clinical Advisor: Instant Diagnosis and Treatment. St. Louis, MO: Mosby; 2000.
Hansen MC. Otosclerosis and sensorineural hearing loss. A clinical study. Archives of Otolaryngology Head and Neck Surgery . 1983;109(9).
Hearing loss prevention. Better Hearing Institute website. Available at: http://www.betterhearing.org/hearing%5Floss%5Fprevention/index.cfm . Accessed January 25, 2012.
Lee SH, Chang Y, Lee JE, Cho JH. The values of diffusion tensor imaging and functional MRI in evaluating profound sensorineural hearing loss. Cochlear Implants International. 2004;149-152.
Living with hearing loss. Hearing Loss Association of America website. Available at: http://www.hearingloss.org/content/living-hearing-loss . Accessed January 25, 2012.
Marshall KG. Family Practice Sourcebook: Evidence-Based Emphasis . St. Louis, MO: Mosby; 2000.
Onion DK. The Little Black Book of Primary Care: Pearls and References. 3rd ed. Malden, MA: Blackwell Science; 1999.
Tierney LM, McPhee SJ, Papadakis MA. Current Medical Diagnosis and Treatment. 40th ed. New York, NY: Lange Medical Books/McGraw Hill; 2001.
DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance : Durga J, Verhoef P, Anteunis L, Schouten E, Kok F. Effects of folic acid supplementation on hearing in older adults: a randomized, controlled trial. Ann Int Med. 2007;146(1):1-9.
