The information below should serve as a general guide only.
Hearing loss can affect people of any age. One in six adults have some degree of hearing loss, which increase to three in four above the age of 75. Children can also be affected, usually due to fluid or infection in the middle ear but also due to congenital problems or viral illness during early childhood.
The mechanism of hearing
We can hear sounds via the ear canal and eardrum by vibrations of the eardrum, ossicles (small bones in the ear) and then the inner ear or cochlea where the sound waves are changed into electrical signals which are passed on to the brain along the auditory nerve.
Types of deafness
The causes of deafness can be broadly grouped into conductive problems in the ear canal and middle ear (conductive hearing loss) or sensori-neural problems, which is a problem with the translation of the sound waves into an electrical signal by the inner (sensorineural hearing loss).
A conductive hearing loss can occur due to wax blocking the ear canal, or infection, a collection of fluid, trauma or fixation of the ossicles in the middle ear. Fortunately they can usually be treated.
A sensorineural hearing loss is due to a problem of the inner ear or of the nerve that carries the signal to the brain. There are many causes, the commonest being that of hearing loss in old age (presbyacusis), but other causes include virus infections, trauma, drugs, noise exposure and congenital causes. Some inner ear problems are reversible, but usually loss is permanent. Extremely rarely it may be due to a growth or tumour in the brain.
Hearing aids are continuing to improve and help to amplify the sounds that are heard by the inner ear and so partially overcome the hearing loss.
When to ask for help from an ENT specialist
You should seek advice urgently (within 24-48 hours) if you have a sudden hearing loss, as treatment should be started within 48 hours of its onset.
You should seek advice if you have a hearing loss in one ear only.
If you notice a gradual deterioration of your hearing and need to discover the cause and get treatment.