Cataracts

Cataract is clouding of the lens of the eye. This means less light can get through to the retina and vision becomes hazy and inconsistent.

The lens is a transparent body behind the iris, the coloured part of the eye. Its function is to focus, that is bend (or refract) light rays to give a clear image to the retina at the back of the eye.

Cataract surgery from ancient to modern

Representation of the effect of cataracts

Causes

The biggest cause of cataracts is age, but in the older age group, there are great differences in severity. Cataracts usually develop gradually, taking anything from a few months to 30 years.

If a cataract starts to interfere with your everyday life, your consultant will usually arrange for it to be removed.  Surgery is often undertaken on a day case basis.

Symptoms

• Things may look misty

• Colour vision changes, mostly yellowing and faded colours

• Difficulty seeing in bright light due to glare

• Seeing double if the cloudiness is in one place

• Glasses may constantly seem scratchedor dirty

Treatment

• Normal Vision is not restored just by removal of the cloudy lens. This is because the lens is important in focussing, so an artificial lens of some kind will have to be substituted

• This is done by inserting a plastic lens permanently into the eye and is called an implant.  Your spectacles will probably need changing approximately 6 weeks after surgery, but they will not need to be thick

• Occasionally, the surgeon is unable to insert an implant and then contact lens or thick glasses may be necessary

• Cataract surgery is usually very successful, but vision could still be blurred if further underlying complications are found behind the cataract

Living with Cataracts

Before your cataract operation you can help yourself by following these tips

• Avoid glare – light shining directly into the eyes or reflecting back off a shiny surface

• Correct Lighting is very important

• Too little light and you cannot see: too much and you may be dazzled

• For close work and reading use direct light from an adjustable fluorescent lamp

• Sunglasses or tinted lenses may help

• On sunny days try a visor or hat with a brim

• Worldwide, cataracts are the most common cause of blindness. However in most cases a simple operation can cure it

• The word ‘cataract’ comes from the Latin for waterfall. People used to think it was caused by a flow of fluid from the brain into the pupil of the eye forming a white membrane there