Hearing loss and deafness

Dr Sanjay Sachdeva
When a stone is thown in water, waves spreads in circles. Similarly a sound source spread waves, which are percieved by the ears. Sound is measured in decibel. For Example, rustling of leaves is low decibel sound, whereas loud sounds, like crackers produce discomfort to the ear.

Hearing loss is the reduced ability to hear. Deafness is the complete inability to hear.
Conduce hearing loss
Conductive hearing loss occurs when something blocks sound waves from reaching the inner ear.
Sensorineural hearing loss is caused by damage to the inner ear or to the nerves that send sound to the brain. Presbycusis, or age-associated hearing loss, also has a genetic component. It makes one deaf over a period time as they age due to the slow decay of sensitive hair cells lining the inner ear. Apart from aging, other causes of hearing loss are circulatory problems, diseases such as diabetes, and long-standing exposure to noise. Without the hair cells, recognizing sounds becomes difficult or impossible.
Treatment
Conductive hearing loss and deafness may at times be treatable by removing the cause of the blockage, for example, wax in the ear canal or fluid in the middle ear. OTOSCLEROSIS, a term used for thickening of middle ear bones can be treated with surgery or with ampliication of sound by using hearing aids.
Sensorineural hearing loss or deafness tends to be permanent because it involves damage to nerves or to the inner ear hair cells. The only method of treatment is a hearing aid worn in the ear, a device that amplifies the volume of sound electronically. Now a days, most of the hearing aids are programmable to make them more effective for use in a variety of situations, such as noisy environments or talking on the phone.
For Sensorineural hearing loss- Most recent Advances is cochlear implant

How Natural Hearing Works
Ear Canal: Sound moves through ear Canal and strikes the eardrum
Eardrum and Bones: Eardrum vibrates bones in the middle ear.
Inner Ear: The motion causes the fluid in the inner ear to move the hair cells.
Hearing Nerve: Hair cells change the physical movement into electrical impluse which is sent to the brain via nerve and enables the person to hear.
A cochlear implant is electronic medical device that replaces the function of the damaged inner ear. Unlike hearing aids, which make sounds louder, cochlear implants bypass the damaged hair cells of the inner ear (cochlea) to provide sound signals to the brain.
Who is Eligible to receive a cochlear Implant
A number of medical and Audiological Assessments are required to determine if as person is candidate for Cochlear Implant.
Generally, the following criteria apply:
* The potential recepient must have a severe to profound sensorineural hearing loss
* They must gain little or no benefit from the use of hearing aids.
* The inner ear must be free from infection.
* They must be medically suitable to undergo surgery.
Expectations From Cochlear Implant
How much benefit a person receives from Cochlear Implant depends on the follwoing factors:-
* Duration of deafness
* Amount of residual hearing
* Age of Implantation
* Status of the hearing nerve
* Post operative rehabilitation
* Motivation and family commitment
Benefits of Cochlear Implant
Some of the benefits of Cochlear Implant are:-
* All implant users have incresed access to environmental sounds
* Many enjoy the ability to understabd speech without lip-reading
* Many can appreciate music.