Cataracts

What are Cataracts?

Cataracts are a natural part of the ageing process. It is estimated that some 50% of people aged 65 and over will suffer a cataract.

A cataract is a clouding of the normally clear lens of the eye, which interferes with the normal passage of light rays to the retina. The result is a general dimming of vision which becomes progressively more blurred as the density of the cloudiness increases.

Causes of Cataracts

Cataracts develop due to:

Ageing; natural changes due the ageing process Injury;
Damage due to a blow or cut to the eye Birth defects
Disease, radiation, chemicals, and excessive ultraviolet light.

Most Cataracts are age related and the liklihood of cataracts developing increases with age.

Age related cataracts develop due to either a build up of protein in the lens, reducing the clarity of the image reaching the retina or from the lens slowly changing to a yellowish/brownish color, adding a brownish tint to vision.

Most age-related cataracts develop from an excessive build up of protein.

When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.

Diagnosis of Cataracts

The most common symptoms are:

Headlights that appear too bright at night
Glare from lamps or the sun,
Halos or haze around lights
Decreased vision in bright light

When a cataract is small, you may not notice any changes in your vision. Cataracts tend to grow slowly, so vision deteriorates gradually. Some people with a cataract find that their vision close up suddenly improves, but this will be temporary. Vision is likely to reduce further as the cataract develops.

Treatments for Cataracts

Cataract surgery has advanced considerably over the last decade
Gone are the days of wearing bottle-lens glasses after cataract surgery. This was necessary when the clouded lens was removed and not replaced with anything. Very high prescription lenses were needed for focusing. Nowadays a cataract can be removed in a simple outpatient operation using a technique called phacoemulsification. This is carried out under local anaesthetic and you can be home within hours. A small plastic lens replaces the natural one and glasses are often not needed after surgery (except for reading).

The operation takes approximately 20 to 30 minutes. The eyelid is held open and surgery is carried out under the microscope while you are fully awake. Stitches are not normally necessary.

The surgeon makes a very small incision in the side of the eye.
Sound waves (ultrasound) are used to liquefy the lens, which is then removed by suction through a small tube.
The artificial lens is inserted in the space left behind. You will not feel anything.
The new lens remains there permanently and does the work of the natural lens. The wound heals naturally, usually without the need for stitches.