Stem Cell Treatment Hearing Loss at SIRM
1. Conductive hearing loss
A conductive hearing impairment is present when the sound is not reaching the inner ear, the cochlea. This can be due to external ear canal malformation, dysfunction of the eardrum or malfunction of the bones of the middle ear. The ear drum may show defects from small to total resulting in hearing loss of different degree. Scar tissue after ear infections may also make the ear drum dysfunction as well as when it is retracted and adherent to the medial part of the middle ear.
Dysfunction of the three small bones of the middle ear; hammer, anvil and stapes may result in conductive hearing loss. The mobility of the ossicles may be impaired of different reasons and disruption of the ossicular chain due to trauma, infection or anchylosis may also result in hearing loss.
2. Sensorineural hearing loss
A sensorineural hearing loss is one resulting from dysfunction of the inner ear, the cochlea, the nerve that transmits the impulses from the cochlea to the hearing centre in the brain or damage in the brain. The most common reason for sensorineural hearing impairment is damage to the hair cells in the cochlea. As we grow older the hair cells degenerate and lose their function, and our hearing deteriorates. Depending on the definition it could be estimated that more than 50% of the population over the age of 70 has an impaired hearing. Impaired hearing is the most common physical handicap in the industrialized world.
Another common reason for hearing loss due to hair cell damage is noise-induced hearing loss. These types of hearing loss are often most pronounced in the high frequency range. This will often interfere with speech understanding, as it is in the high frequency range that we find the consonant sounds that are most important especially in noisy surroundings. Head trauma, ear infections, tumours and ototoxic drugs such as gentamyacin are other reasons for sensorineural hearing loss.
Mixed hearing loss
Mixed hearing loss is a combination of the two types discussed above. Chronic ear infection that is a fairly common diagnosis could result in a defect ear drum and/or middle ear ossicle damages.
Stem Cell Treatment for Hearing Loss
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