Hearing loss

What is hearing loss?
Hearing loss is when your hearing worsens; deafness is when hearing loss becomes profound.
The ear receives sounds from the environment and transmits them to the brain. The ear consists of three parts. The outer ear is those parts of the ear that are visible on the sides of your head plus the canals that enter into your head. These canals lead to the eardrum, which is attached to three small bones, the 'ossicles', that amplify and conduct sound to the inner ear.
What causes hearing loss and who is at risk?
Two types of hearing loss occur, conductive and sensorineural, depending on which part of the ear is affected. Conductive hearing loss is caused by anything that blocks the conduction of sound from the outer through to the inner ear. The causes include:

middle ear infections,

collection of fluid in the middle ear ('glue ear' in children),

blockage of the outer ear (by wax),

damage to the eardrum by infection or trauma,

otosclerosis, a condition in which the ossicles of the middle ear become immobile because of growth of the surrounding bone,

Rarely, rheumatoid arthritis affects the joints between the ossicles.



The other type of hearing loss is called 'sensorineural' and refers to damage to the pathway for sound impulses from the hair cells of the inner ear to the auditory nerve and the brain. The causes include:

age-related hearing loss,

acoustic trauma (such as a loud noise) to the hair cells,

viral infections of the inner ear (may be caused by viruses such as mumps, measles, chickenpox),

Meniere's disease (abnormal pressure in the inner ear),

certain drugs, such as aspirin, quinine and some antibiotics, affect the hair cells,

acoustic neuroma (a benign – non-cancerous – tumour of the auditory nerve),

viral infections of the auditory nerve (caused by viruses such as mumps and rubella),

meningitis (infection of the coverings of the brain),

encephalitis (infection in the brain),

multiple sclerosis that affects auditory nerve pathways in the brain,

brain tumours,

strokes.



If a pregnant woman has rubella, the foetus is at risk of being born with profound deafness. For this reason, girls are vaccinated against rubella before child-bearing age.
Some children are born deaf because of different problems with their development.
What are the common symptoms and complications of hearing loss?
Hearing loss and deafness are symptoms of the disorders that cause them. Depending on the cause, they may be associated with other symptoms.
Hearing loss may be very gradual, as in age-related hearing loss, or it can be very sudden, as in some viral infections of the inner ear.
What is the treatment of hearing loss?
Self-care action plan
If you, your friends or your family think that your hearing may be deteriorating, you should always see your doctor to find out the cause.
Treatment
The treatment of hearing loss depends on the cause, which must be discussed with a doctor. Infections are treated with antibiotics, blockages of the outer and middle ears can be cleared, damaged eardrums can be repaired surgically and otosclerosis can be treated effectively by replacement of the affected ossicles with tiny artificial bones. Some causes of sensorineural hearing loss can also be cured. For example, an acoustic neuroma (a benign tumour of the auditory nerve) can be removed surgically.