What is cataracts?

What is cataracts?

What is it?

Cataracts are cloudy patches that develop in the clear lens inside your eye, stopping some of the light from reaching the back of the eye, and causing blurred or misty vision. They are very common – a significant cause of impaired vision worldwide.

Ageing is the primary cause of cataract and a leading cause of vision loss in New Zealand.1 Although rare types of cataracts affect babies and young children, the condition is much more common in older people.

What are the symptoms?

Cataracts develop over many years and problems may at first be unnoticeable. They often develop in both eyes, although each eye may be affected differently. You will usually have blurred, cloudy or misty vision.


  • you may find it more difficult to see in dim or very bright light
  • bright lights may be dazzling or uncomfortable to look at
  • colours may look faded or less clear with a yellow or brown tinge
  • you may see a haloes (circles of light) around bright lights, such as car headlights or street lights

Cataracts are not painful and don't make your eyes red or irritated.

What causes it?

In most people, cataracts simply develop as they get older. Several other factors may also increase your risk of developing cataracts, including:

  • a family history of cataracts
  • smoking
  • lifelong exposure of your eyes to UV light
  • taking steroid medication over a long time
  • previous eye surgery or injury
  • certain health conditions, such as diabetes

What about driving?

You can drive when you have cataracts, provided you still meet the legally required vision standards for driving. There is no need to tell the License Authority about your cataract unless you cannot meet the standards. Your Specsavers optometrist can advise you on this.

What help is available?

When you have your eyes examined by your Specsavers optometrist, they will use a variety of instruments to look inside and check for cataracts.

If your cataracts are mild, stronger glasses and brighter reading lights may be helpful for some time. However, most cataracts get worse over time (often many years) so eventually you may need treatment.

The only treatment that is proven to be effective for cataracts is surgery. This will usually be recommended if your loss of vision has a significant effect on your daily activities, such as driving or reading.

If it is thought you have cataracts that are affecting your quality of life, you can be referred to an ophthalmologist, who can confirm the diagnosis and plan your treatment. If deemed appropriate, your ophthalmologist will organise cataract surgery. The cloudy lens will be replaced by a clear synthetic lens that stays in your eye for the rest of your life.

Will I need new spectacles after my cataract operation?

It may take several weeks for your eyesight to settle down following cataract surgery. Following this it is possible that your optometrist or ophthalmologist may recommend a change in your spectacle prescription.

Will the cataract come back?

The synthetic lens that is inserted at the time of cataract surgery will always stay clear. However, occasionally a film or membrane can grow behind this lens, blurring your vision. This may be amenable to improvement with a laser treatment by your ophthalmologist.

Do cataracts only occur in one eye?

If you have had a cataract removed from one eye, it is likely that you will need the same treatment for the other eye at some point in the future.

  • 1Southern Cross Healthcare Group 2013, Cataracts – causes, symptoms, treatment, surgery, Southern Cross, New Zealand