How does deafness happen?
Deafness happens when one or more parts of the ear are not working as well as they should. There are two reasons for this.
1. Sound cannot get through the ear easily. This is known as conductive deafness.
2. Sound is not picked up well by the hair cells in the cochlea or the hearing nerve. This is known as sensorineural or nerve deafness.
Conductive deafness happens when sound cannot pass easily through the outer and middle ear to the cochlea. This could be because of temporary blockage, (a blockage that happens for a short time) or because someone was born without a pinna or ear canal.
Lots of children under the age of 10 years have a temporary blockage caused by a build up of fluid in their middle ear. This is known as ‘glue ear’. Glue ear often gets better on its own but some children have an operation to have grommets.
Sensorineural deafness happens when there is a fault in the inner ear. Usually this is because the hair cells in the cochlea or the hearing nerve are not working properly.
There are lots of reasons for someone being deaf.
- Some children are born deaf. Their deafness may be genetic (passed on through the family), or caused by being born very early, or by an infection caught before they were born.
- Some children become deaf when they are young. Their deafness may be genetic (passed on through the family), or caused by an illness or infection (such as meningitis, measles or mumps), or caused by a medicine that was given to treat a serious illness.
- And lots of adults become deaf. Their deafness may be caused by listening to too much loud noise, or a head injury, or just because they are getting older.