Open a PDF version to print this topic

HealthInfo Waitaha Canterbury

Overview of cataracts

Tirohanga whānui ki te karu puata kore

Larger text

To increase the text size on this page, click the green "+" button at the top right of the page until the text is big enough.

A cataract is when the clear lens in your eye becomes cloudy. This can lead to reduced vision.

The lens of your eye works like the lens of a camera. It focuses the light onto the retina at the back of your eye. If the lens is no longer clear, light cannot pass through it and your vision becomes cloudy.

Cataracts are one of the most common causes of reduced vision but are easily treated. They usually happen with ageing, but there can be other causes.

Things that can increase your risk of getting a cataract include:

Symptoms of cataracts

CataractsYou may not have any symptoms from a cataract.

As a cataract grows, you may notice:

Diagnosing cataracts

If you're concerned that you might have a cataract, see an optometrist or ophthalmologist (specialist eye doctor) for a detailed eye examination.

Treating cataracts

Once vision loss is affecting your normal lifestyle, cataracts are treated with surgery. They can be treated at any stage. There is no need to wait for the cataract to "ripen" before it can be treated.

Surgery involves removing the cloudy natural lens and replacing it with a new clear lens.

This is a simple procedure usually done under a local anaesthetic.

Reducing your risk of getting cataracts

  HealthInfo recommends the following pages

On the next page: Treating cataracts

Written by HealthInfo clinical advisers. Last reviewed March 2023.


Page reference: 117715

Review key: HICAT-117496