Hearing loss can be divided into two types: conductive hearing loss (caused by some sort of mechanical problem in the external or middle ear) or sensorineural hearing loss (caused by disorders of the inner ear, hearing nerve or associated brain structures).

Conductive hearing loss is often reversible and can be due to:

• blockage of the ear by e.g. wax, inflammation, infections or middle ear fluid
• poor sound conduction because of e.g. holes or scarring in the eardrum or the bones of the middle ear (ossicles) becoming fixed and rigid.

Sensorineural hearing loss is generally not reversible and can be caused by:

• genetic make-up (this could include congenital conditions i.e. those you are born with, or late-onset hearing loss)
• head injury
• tumours
• infections
• certain medications
• exposure to loud noises
• the aging process (a significant hearing loss is experienced by about one third of people aged over 70 years).

Some of the signs you might notice that indicate you have a hearing loss include:

• having to turn up the volume on the TV or radio
• finding it hard to hear someone you are talking with
• finding it hard to hear in a group situation where there is background noise e.g. in a restaurant
• having to ask people to repeat themselves
• you find people's speech is unclear - they are mumbling

Hearing loss can be partial (you can still hear some things) or complete (you hear nothing) and may occur in one or both ears.

Treatment

Treatments for hearing loss range from the removal of wax in the ear canal to complex surgery, depending on the cause of the loss. One of the most common treatments for hearing loss is the use of a hearing aid. The type of aid you get depends on the cause of your hearing loss and how bad it is, as well as what your preferences are in terms of comfort, appearance and lifestyle.

If your hearing loss is severe to profound, you may be suitable for a surgical procedure known as a cochlear implant. In this procedure, a small cut (incision) is made behind your ear and a device is implanted that can bypass the damaged parts of your ear. The surgery usually takes 2-3 hours and is performed under general anaesthesia (you sleep through it). You may be able to go home the same day or have to spend one night in hospital.