
A
cataract is a clouding of the lens that can cause problems with your
vision. It may make the black pupil of the eye look grey or very pale.
The lens is located behind the coloured iris and its function is to help focus the light entering the eye.
The
lens is made up of water and lens fibres, which let light pass through
onto the retina. Sometimes some of the fibres change their structure
and organisation and loose transparency. It prevents some light from
reaching the retina and interferes with vision. This is a cataract.
In its early stages, a cataract may not cause any changes in vision.
However, over time, it may affect a larger area, clouding more of the
lens and making it harder to see.
Although scientists are investigating all the time, no one knows for
sure what causes cataracts. It is generally thought to be hereditary,
and that eye injuries, radiotherapy, diabetes and some drugs may play a
part.
Some recognised risk factors
however, include smoking or excessive drinking, diabetes and high
exposure to sunlight. Cataracts are also known to be more common in
women than men.