Cataract

Please click here if you would like information about cataract surgery.

What is a cataract?

Inside your eye is a lens. This lens allows light that enters the eye to focus on the back of the eye. As we age, the lens inside the eye becomes cloudy. A cloudy lens is called a cataract.

There are many types of cataract. The most common cataract causes a yellowing of the lens and is called a 'nuclear sclerotic' cataract (below).

If a cataract is present for a long time, it matures. A mature cataract has a very white appearance, that can sometimes be visible even with the naked eye (below).

What are the symptoms of cataract?

Usually cataracts will cause symptoms, including:

blurred vision
double images or ghost images
glare or sensitivity to lights
haloes around lights or night-driving difficulties
recent changes in glasses prescriptions (myopic shift).

What causes cataract?

Most commonly, cataract is caused by age. They are very common, most people older than 70 will have some early cataract.

Other causes of cataracts include:

medications (such as steroids)
other eye diseases (such as uveitis or retinitis pigmentosa)
congenital or hereditary
diabetes
eye trauma.

How fast do cataracts develop?

Generally, cataracts develop very slowly, over many years. Occasionally, they may develop quickly after trauma, or if you are diabetic.

When is the correct time to remove cataracts?

In the past, we only removed cataracts when they were considered 'mature'. This was in part due to the poorer outcomes associated with cataract surgery, compared to current, modern techniques. These days, we tend to remove cataracts as soon as they start causing symptoms.

Everybody has different visual requirements and as such the timing of cataract surgery will be different for different people. Therefore, the decision to remove a cataract, or leave it alone, will be made after discussing your particular needs with your surgeon.

What is the treatment of cataract?

The only treatment for cataract is to remove it with an operation. After the cataract is removed, a new lens is inserted into the eye. This new lens is needed to allow light to focus again on the retina at the back of the eye.

The operation usually takes about 10 minutes, but it can be longer if you have a larger cataract. Ordinarily, you will go home about 1 hour after the procedure.