Cataracts

A cataract is a clouding of the lens of the eye.

Normally the lens in the eye is clear. It focuses light through the retina to produce an image. When the lens becomes cloudy from a cataract, light cannot pass through to the retina, nerve signals are not sent to the brain and an image becomes blurred.

Cataracts can eventually cause blindness if not treated. Cataract removal is a safe and effective procedure. 

In this article:

• Cataracts signs and symptoms
• Cataracts risk factors
• Cataracts diagnosis
• Cataract surgery and management

Cataracts signs and symptoms

Cataracts develop slowly and some people are unaware of any changes in vision. Cataracts can affect one or both eyes. As the clouding of the lens gets larger, vision becomes blurred, dull or tinted.

Signs and symptoms of cataracts include:

•  Cloudy or blurred vision
•  Sensitivity to light and glare
•  Loss of colour perception
•  Spots before the eyes
•  Frequent changes in glasses prescription 

Cataracts risk factors

Cataracts commonly affect people as they age, especially after 65. However, they can develop in younger people and in rare cases at birth. 

Risk factors for cataracts include:

•  Increasing age
•  Exposure to ultraviolet light
•  Smoking
•  Diabetes
•  Family history
•  Injury 

Cataracts diagnosis

If a person experiences any signs or symptoms of cataracts they should see their doctor. An optometrist can detect any changes in the lens of the eye during regular eye exams. Changes can often be seen before symptoms appear. An optometrist will refer a person to an ophthalmologist, a medical doctor specialising in eye surgery when necessary. 

Cataract surgey and management

Surgery is an option considered on an individual basis depending on how much the damage interferes with daily life. The effectiveness of surgery can depend on the existence of other conditions that may limit a person’s vision including macular degeneration and glaucoma.

An ophthalmologist performs cataract surgery. It is usually a day procedure under a local anaesthetic and involves replacing the damaged lens with a plastic intra-ocular lens (IOL). A person will also be prescribed new glasses or contact lenses. Increasing light and using a magnifying glass are some other ways to help people with cataracts and poor vision.

Tip

People can protect themselves from cataracts by avoiding long-term exposure to ultraviolet light. Avoid the sun between 10 am and 4 pm. Wear a wide brim hat and sunglasses that meet Australian standards if outdoors. The eyes should be examined regularly. 

Relate articles

• What is low vision?
  
• Helping someone at home with low vision
  
• Low vision aids and adaptive technology
  

References
Vision Australia 2008
Fact sheet, Cataracts
Accessed 26/07/08

Optometrists Association Australia 2008
Cataracts
Accessed 26/07/08