Otosclerosis involves formation of new spongy bone around the stapes and oval window. It results in progressive conductive hearing loss due to immobilization of the middle ear bones. It can occur in one or both ears. This condition is genetic and typically begins between ages 15-35. Otosclerosis can cause mild to severe hearing loss, but it rarely leads to complete loss of hearing. The most effective treatment is reconstruction or replacement of the stapes, but hearing aids can be used as well.
Tinnitus is the perception of ringing, buzzing, hissing, or whistling sounds in one or both of the ears. This noise isn’t from an external sound, and usually other people can’t hear it. It is often associated with an underlying problem such as hearing loss, ear injury, or a problem with the circulatory system. It can be constant or come and go. Tinnitus can be divided into two categories:
Conductive hearing loss is caused when stimuli is not conducted from the eardrum and ossicles to the inner ear. It can be due to impacted cerumen, fluid, foreign bodies, otosclerosis, and Paget’s disease.
Sensorineural hearing loss happens after inner ear damage or because of issues with the nerve pathways between the inner ear and the brain. Sensorineural hearing loss may have a genetic cause or be due to exposure to loud noises, an infection (e.g., bacterial meningitis), trauma, or illness. Some drugs can also cause this type of hearing loss. Antibacterial drugs known as aminoglycosides, chemotherapeutic agents, certain antimalarial drugs, some loop diuretics, and salicylates (e.g., aspirin) are all associated with ototoxicity and potential hearing loss. The damage to the inner ear structures due to these drugs in some cases is permanent. It depends on the dose and duration of the drug treatment.
There are two screening techniques used to assess hearing in neonates:
A cochlear implant can be used to help restore some hearing function for those who have hearing loss or impaired hearing. It is a small electronic device that has an external component and an internal component. The external component sits near the ear and contains one or more microphones that pick up sound. The device may also contain some sound filters to more accurately isolate sound frequencies in the audible voice range. This helps with speech recognition. The microphone then passes the sound wave energy to a receiver that passes an electrical current to an array of electrodes surgically implanted in the cochlea. As the electrical signals stimulate the cochlear tissue, auditory neurons are depolarized in an area of the cochlea that approximates a section normally stimulated by a similar but natural sound wave frequency.
An implant does not restore normal hearing. Instead, it can give a hearing impaired person a useful representation of sounds in the environment and help him or her to understand speech. Studies have shown that when young children get a cochlear implant, they are able to comprehend music, speech, and environmental sounds at a faster rate than children with comparable hearing deficiencies who do not get an implant. Some adults who have severe hearing loss may also choose to get a cochlear implant. For these adults, the device will help them as they learn to associate the signals from the implant with sounds they remember, including language.
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