WHAT IS A CATARACT?

The term cataract is used to describe a clouding within the natural lens of the eye. A cataract is not a growth, or a film across the eye. When light enters the eye, it passes through the cornea (the eye’s clear front window), and then through the pupil. Behind the pupil is the lens of the eye. The lens focuses the light rays onto the retina at the back of the eye. The retina is responsible for the signal that is sent from the eye to the brain. The eye generally functions like a camera with a system of lenses (cornea and lens), aperture (pupil) and film (retina).

When the lens becomes clouded with the development of a cataract, light is distorted and is not focused clearly on the retina. Vision is reduced and blindness can eventually result. Almost everyone who lives a long life will develop cataracts. The cloudiness does not spread from one eye to the other but cataracts will usually develop in both eyes at some time. Most cataracts mature slowly over several years however some cataracts may develop rapidly within a few months.

The word cataract is derived from the Greek word katarakta, which means waterfall. The water in a river is normally clear, however when the water reaches a waterfall it turns milky white. The lens of the eye is normally clear, however with the development of a mature cataract the lens will turn completely opaque and milky. Even without the aid of a microscope, the pupil will turn milky white like a waterfall.

Return to Top

WHAT CAUSES CATARACTS TO DEVELOP?

The most common cause of cataracts is ageing. Age-related cataracts develop as a result of exposure to UV light as well as natural changes within the lens.

Some cataracts may also result from the use of certain medications such as cortisone or some diseases such as diabetes. Smoking may speed up the progression of certain types of cataract. Occasionally an injury or blow to the eye may cause a traumatic cataract. Sometimes cataracts run in families and a small number of babies are born with congenital cataracts.

Fortunately most cataracts can be successfully removed and vision restored through modern microsurgery.

Return to Top

SYMPTOMS OF A DEVELOPING CATARACT

Cataracts, and their symptoms, vary from person to person. Some common symptoms of cataracts are:

• Blurred vision
• A gradual loss of colour vision - objects appear duller
• Difficulty reading
• An increasing need for more light to see clearly
• Glare
• A tendency to become more near-sighted because of the increasing density of the lens
• Frequent changes of prescription glasses
• An increased sensitivity to sunlight or car headlights
• Double vision, even if only one eye is open

Cataracts are not painful.

Most people who develop cataracts experience only some of these symptoms.

It is important to realise that these symptoms do not necessarily indicate the presence of a cataract. A person experiencing these problems should have a complete eye health check and visual examination by their Optometrist or Ophthalmologist. If necessary, the Optometrist will then refer to an experienced Ophthalmologist for surgery.

In the past, people with cataracts were told to wait until their cataracts
‘ripened’ or ‘matured’. This meant living through years of gradually
deteriorating vision. At the Cataract Care Centre and Tasmanian Cataract Clinic modern microsurgical techniques are used which are minimally invasive, resulting in far fewer complications and a rapid recovery.

The trend now is to operate earlier than in the past. A cataract is generally
removed when deteriorating vision interferes with a person’s lifestyle and they want to see better.

Return to Top