Cataracts

A cataract is a clouding of the eye's natural lens. It is common with age and can gradually make everyday vision less clear.

What does a cataract do?

The lens sits behind the coloured part of the eye (the iris) and helps focus light on the retina. When the lens becomes cloudy, light does not pass through it as clearly. Cataracts may affect one or both eyes, but they do not spread from one eye to the other.

Common changes you may notice

• Blurred, hazy or less vivid vision
• Glare from sunlight, lamps or headlights, sometimes with halos around lights
• Difficulty seeing in low light or while driving at night
• Colours appearing faded or yellowed
• Double vision in one eye
• Needing to change glasses more often than usual

Why do cataracts develop?

Most cataracts are age-related. They can also be associated with diabetes, long-term steroid use, smoking, previous eye injury or surgery, radiation exposure, family history, and some eye diseases. Cataracts can occasionally be present in children or develop after an injury, so a new change in vision should be assessed rather than assumed to be age-related.

When is treatment needed?

In the early stages, brighter lighting, glare reduction and an updated glasses prescription may improve day-to-day comfort. Surgery is the only way to remove a cataract. It is usually considered when vision is interfering with activities that matter to you, such as reading, working, recognising faces or driving safely—not simply because a cataract has been detected.

Your eye specialist may also recommend surgery when the cataract prevents them from monitoring or treating another eye condition. The expected benefit depends on the health of the rest of the eye; cataract surgery cannot restore vision lost from problems such as advanced glaucoma, macular degeneration or diabetic retinal disease.

This guide provides general information and does not replace an individual examination or the advice of your eye-care team.