By the age of 14 years, the prevalence of hearing loss is estimated at 4 per thousand, or approximately 3, children. The causes of hearing loss may be genetic, due to trauma or illness, or may be unknown. A recent Review of Audiology Services stated:
Hearing Loss Topic Guide Facts on Hearing Loss To understand hearing loss it is important to understand how normal hearing takes place. There are 2 different pathways by which sound waves produce the sensation of hearing: In air conduction, sound waves move through the air in the external auditory canal the "ear canal" between the outside air and your eardrum.
The sound waves hit the tympanic membrane eardrum and cause the tympanic membrane to move. The bones in the middle ear are connected to the tympanic membrane.
When the tympanic membrane moves, this movement is transmitted to the bones. These 3 bones are called the malleus, the incus, and the stapes. Movement of the stapes causes pressure waves in the fluid-filled inner ear.
The cochlea is an inner ear structure surrounded by fluid. It contains multiple small hairs. Pressure waves in the fluid cause the hairs to move. This movement stimulates the auditory nerve.
Different frequencies of noises stimulate different hairs on the cochlea, which translate to the sensation of sounds of different pitch. Hearing by bone conduction occurs when a sound wave or other source of vibration causes the bones of the skull to vibrate.
These vibrations are transmitted to the fluid surrounding the cochlea and hearing results. What Causes Hearing Loss? Share Your Story There are 2 basic types of hearing loss, which are called conductive and sensorineural.
Conductive hearing losses result from physical problems with the movement of the sound wave through the ear. A simple example is blockage of the ear canal. Obstructed external ear canal - Cerumen wax build-up, hematoma blood collectionor foreign body in the ear canal.
This is one of the most common causes of hearing loss and the easiest to fix. This may be associated with a collection of skin called a cholesteatoma Sensorineural causes: Sensorineural causes are from damage to the hair cells or nerves that sense sound waves.
Acoustic trauma - Prolonged exposure to loud noises causes the hair cells on the cochlea to become less sensitive.
Barotrauma pressure trauma or ear squeeze - Usually in divers Head trauma - A fracture of the temporal bone can disrupt the nerves of the auditory system or the cochlea directly Ototoxic drugs - Certain drugs can affect hearing by damaging the nerves involved in hearing.
Usually this occurs when large or toxic doses are used but may also occur with lower doses. Diuretics including furosemide and ethacrynic acid Salicylates aspirin and nonsteroidal anti-inflammatories NSAIDs such as ibuprofen and naproxen Antineoplastics cancer drugs Vascular diseases problems with blood vessels include sickle cell diseasediabetesleukemiapolycythemiaand diseases in which excessive blood clotting occurs.
Children and adults with kidney problems are more susceptible to sensorineural hearing loss.Some causes of sensorineural hearing loss can also be cured.
For example, an acoustic neuroma (a benign tumour of the auditory nerve) can be removed surgically. If there is no cure for the hearing loss (as with age-related hearing loss), a hearing aid usually helps most people, whether the hearing loss is conductive or sensorineural. Sudden onset hearing loss (SOHL) has a number of causes, ranging from the simple and reversible to the profound and perma-nent.
The sequelae of a sudden loss of hearing can be significant. SOHL causes great concern for the patient. It is when there is a 30 dB or greater hearing loss over less than. Overview. Hearing loss that occurs gradually as you age (presbycusis) is common.
About 25 percent of people in the United States between the ages of 55 and 64 have some degree of hearing loss. Hearing loss — Comprehensive overview covers symptoms, treatment, prevention of age- and noise-related hearing loss interpret and file information about the sound.
The comparison and analysis of all the signals that reach the brain enable you to detect certain sounds and suppress other sounds as background noise. Some causes of. Kelsell et al. () provided a comprehensive review of connexin mutations in skin disease and hearing loss.
They discussed the dominant connexin disorders of keratoderma and/or hearing loss and the autosomal recessive nonsyndromal hearing loss due to connexin mutations. NIH study uncovers clues about why common cancer drug causes hearing loss Researchers find target to protect hearing during chemotherapy treatment.
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