Types of Hearing Loss and Deafness
More than 37 million people in the U.S. have a hearing loss that impacts their abilities to communicate. Hearing loss occurs as a result of some form of damage or malfunction within the auditory system. A variety of factors can cause damage or malfunction. Some forms of hearing loss are hereditary, while others can stem from infections, aging, medications, disease, head injury or excessive noise exposure. In rare instances hearing loss can result from an acoustic neuroma (aka vestibular schwannoma or VS) -- a tumor occurring on the balance nerve.
Microscopic Normal Hair Cells & Microscopic Damaged Hair Cell
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Some types of hearing loss may be signs of a serious medical condition. If you notice a sudden change in your hearing or an onset of asymmetrical or unilateral hearing loss (hearing loss in one ear), you should have an evaluation by an ear specialist – an otolaryngologist (ENT), otologist or neurotologist. A complete otologic examination by an ear, nose and throat (ENT) physician can determine what type of hearing impairment may exist, its possible causes, and treatment options.
Conductive Hearing Loss
Hearing loss can be conductive or sensorineural in nature. Conductive hearing loss occurs when excessive earwax or a disease or disorder, such as damage to the eardrum or middle ear bones due to infection or otosclerosis1, impedes the ability of either our middle or outer ear to transmit sound to the inner ear. Medication and/or surgical reconstruction techniques often can correct mechanical functions of the eardrum or ossicular chain. Blockage of the outer ear canal also can result in hearing loss. In such cases, an ENT physician often can provide treatment to improve hearing.
Sensorineural Hearing Loss
Sensorineural hearing loss is nerve-based. It occurs when either the microscopic hair cells of the inner ear or nerve fibers, which transmit signals to the brain, are damaged or compromised. In most cases, this type of hearing loss is permanent and irreversible.
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Deafness is the complete loss of hearing in one or both ears. Hearing impairment can mean either complete or partial loss of the ability to hear. A person is said to have a profound hearing loss when they are unable to perceive sound even with the help of hearing aids. Speech perception involves another aspect of hearing, that of the perceived clarity of a sound rather than its amplitude. Depending on the cause, hearing loss may be treated medically, surgically or through devices such as hearing aids and Cochlear Implants.
TinnitusHearing loss is one of many different health factors that can be associated with tinnitus, a symptom usually identified as a ringing or roaring sensation in the ear. Approximately 80% of patients with hearing loss report experiencing tinnitus. While some degree of head noise is a normal occurrence in everyone, it can be debilitating for some people. In the latter case, a licensed physician should be consulted to check for a serious medical condition. Audiologists and other trained professionals can offer devices and techniques to help manage or minimize debilitating tinnitus, and patients sometimes get relief through stress control, ample rest, exercise, and avoidance of caffeine and other dietary stimulants.
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Medications and Hearing Loss
Certain medications may cause temporary or permanent hearing-related side effects in some individuals at certain dosages. Categories of these medications include salicylates and other anti-inflammatory agents, aminoglycosides, hydrocodone, antineoplastics (for cancer chemotherapy), loop diuretics, and cinchona alkaloids. Contact your physician if you are concerned about a particular medication that you are taking.
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Mixed Hearing Loss
Sometimes people can have a combination of conductive and sensorineural impairment, commonly referred to as a mixed hearing loss. Multiple disorders or a single disease, such as otosclerosis that can spread to both middle and inner ear structures, can result in a type of mixed hearing loss.
Otosclerosis is a common hereditary disease that typically affects the mobility and function of the stapes bone by producing an abnormal growth of spongy bone along the walls of the middle ear. This type of specific type of common impairment is called stapedial otosclerosis and is often correctable by surgery. When otosclerosis spreads to the inner ear, it is called cochlear otosclerosis, and can cause a permanent sensorineural hearing impairment due to interference with the nerve function.
Exostoses are bony outgrowths of the external auditory canal. They typically line both the front and back of the canal and can cause narrowing of the canal, which can be extensive. Exostoses occur more often in people exposed to cold water and wind, such as surfers and divers (so, it's sometimes called "surfer's ear").
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Acoustic Neuromas & NF2
Acoustic Neuromas are benign tumors that occur on the hearing, facial and balance nerves inside the brain. The temporal bones sit on each side of the skull and enclose the hearing and balance organs.
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