Introduction

This information tells you about an operation to remove a cloudy lens (a cataract) in your eye. It explains how the operation is done, how it can help, what the risks are, and what to expect afterwards.

The benefits and risks described here are based on research studies and may be different in your hospital. You may want to talk about this with the doctors and nurses treating you.

What is cataract surgery?

If you have a cataract, it means the natural, clear lens in your eye has become cloudy. In a cataract operation your eye surgeon will remove the cloudy lens and put a clear, artificial lens in its place.^[1]

Your lens sits behind the coloured part of your eye (the iris) and helps you to see things in focus.

In a normal eye, the natural lens is clear.

When you look at something, light comes into your eye through the hole in the centre (the pupil) and passes through the lens to the back of your eyeball (the retina). The lens focuses the light onto nerve cells in your retina. These nerve cells send signals to your brain. Your brain then tells you what the image is. If your lens is cloudy, the image formed on the back of your eye will be blurred. It's a bit like looking through a dirty windscreen or frosted glass.

Different parts of the lens can become cloudy. Cataracts often begin as clouding around the edges of the lens. You may notice that you get a lot of glare or a 'halo' effect around bright lights, or when the sun is low in the sky. If you drive, you might find oncoming headlights more difficult to cope with than before.^[2] Cataracts can also start in the middle of the lens, which makes your vision foggy.

As the cataract grows:

• Your sight becomes blurry

• You keep having to change the prescription of your glasses

• You may have double vision

• You may find it hard to tell the difference between some colours, especially shades of blue

• You may see 'halo' effects around lights, especially at night.

Cataracts are common. Most are caused by ageing. About one-third of people over 65 have cataracts in one or both eyes.^[1] Getting older and exposure to bright sunlight are the main reasons people get cataracts. Having diabetes, smoking, and drinking too much alcohol may also increase your risk of cataracts. Over 200,000 cataract operations are done in the UK each year.

A cataract operation can:

• Help you to see better

• Stop your poor sight interfering with your life.

Not everyone with a cataract needs an operation. Doctors usually suggest the operation when your cataract interferes with your daily life rather than when your eyesight reaches a particular score on a sight test.^[1] Your cataract may mean you can't see well enough to read, work, play a sport, go shopping, or drive a car.^[3] Some people manage with their cataract for longer than others because their poorer sight doesn't affect them much.^[4] For example, a person whose main hobby is listening to music may decide they need treatment later than a person who loves bird watching.