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Hearing loss
Definition:
Hearing loss is the total or partial inability to hear sound in one or both ears. See also: Hearing loss of aging Text Continues Below
Alternative Names:
Decreased hearing; Deafness; Loss of hearing Considerations:
Minor decreases in hearing are normal after age 20. Hearing problems usually come on gradually, and rarely end in complete deafness. There are many causes of hearing loss. They can be divided into 2 main categories: - Conductive hearing loss (CHL) occurs because of some mechanical problem in the external or middle ear. The three tiny bones of the ear (ossicles) may fail to conduct sound to the cochlea or the eardrum may fail to vibrate in response to sound. Fluid in the middle ear can cause CHL.
- Sensorineural hearing loss (SNHL) results from a dysfunction of the inner ear. It most often occurs when the tiny hair cells (called cillia) that transmit sound through the ear are injured. This type of hearing loss is sometimes called "nerve damage," although this is not accurate.
CHL is often reversible -- SNHL is not. People who have both forms of hearing loss are said to have mixed hearing loss. Screening for hearing loss is now recommended for all newborns. In children, hearing problems may cause speech to develop slowly. Ear infections are the most common cause of temporary hearing loss in children. Fluid may linger in the ear following an ear infection. Although this fluid can go unnoticed, it can cause significant hearing problems in children. Any fluid that stays longer than 8 - 12 weeks is cause for concern. Preventing hearing loss is more effective than treating it after "the damage is done." Common Causes:
Genetic:
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