You used to have normal 20/20 vision. Everything was sharp and in focus. There were no blurred objects close to you or far away.

But, recently, things have changed and your optometrist or ophthalmologist has prescribed a pair of glasses or contact lenses, making you one of the more than 10 million Australians living with a long-term eye problem.

According to the National Health Survey (2004 – 05), approximately 5.3 million Australians report to be far-sighted, while about 4.3 million say they’re short-sighted. Approximately 9.4 people wear glasses or contact lenses in order to correct sight.

Are you one of them? Find out more about your specific vision problem:

1. Near-sightedness

What do images look like?


Objects close by are clear and in focus, but everything far away looks blurred and hazy.

Why?


If the eyeball is too wide (like a ball being squeezed from the top and bottom), mainly because of genetic factors, or if the cornea is too curved, light rays focus on a point of the retina instead of on the retina itself. Some people even struggle to see objects right in front of them clearly.

How many people are affected?


It’s very common: one in three people are affected.

How can it be corrected?


With glasses or contact lenses. Laser surgery can enable people with a low degree of near-sightedness to stop using their spectacles or contact lenses while people who are badly near-sighted may afterwards be less dependent on them. Laser surgery can be done only once the condition has stabilised, usually after the age of 18.

2. Presbyopia

What do images look like?


Objects that are close, such as the text in a magazine, are out of focus. The afflicted person has to hold the text further away to read it. When the person looks up, he initially finds it difficult to focus on distant objects.

Why?


After the age of 40, the lens of the eye becomes more rigid and less elastic.

How many people are affected?


Almost all people need reading glasses as they grow older.

Even people over 40 find it more difficult to read or see properly when they’re tired. Your eyes may continue to get weaker until you’re well into your sixties, after which the condition stabilises.

How can it be corrected?


With reading glasses. You can buy a pair at your pharmacy but have your eyes tested by an optometrist in case you have other problems.

3. Far-sightedness

What do images look like?


Far-sightedness is the opposite of near-sightedness; everything far away is clear and in focus but objects close by are blurred and hazy. In extreme cases, both close objects and distant ones may be out of focus.

Why?


If the eyeball is too flat (like a ball being squeezed from the front and the back), light rays are focused behind the retina instead of directly on the retina.

How many people are affected?


As mentioned above, about 5.3 million Australians are affected by the condition, which is often diagnosed even before a child goes to school. The eyes of children born with a degree of far-sightedness may tire more easily and they may develop headaches if they read a lot. Farsightedness can cause a squint.

How can it be corrected?


With glasses or contact lenses. Laser surgery may be helpful in some cases.

4. Astigmatism

What do images look like?


Everything far away and close by, looks slightly out of focus. It’s difficult to see fine details clearly. Usually one side is more out of focus than the other. Sometimes it seems as if vertical lines are leaning to one side like the Tower of Pisa.

Why?


Light is focused on more than one point on the retina because the shape of the cornea is uneven. Some people are born like that. Instead of being round like a soccer ball the retina has a slightly oval shape – more like a rugby ball.

How many people are affected?


About three in 10 people have a degree of astigmatism. Most don't even notice it. However, your eyes tire easily and you may get headaches. People who are near-sighted or far-sighted often also have astigmatism. Astigmatism never really gets better or worse.

How can it be corrected?


With glasses or contacts. Laser surgery can repair mild cases.

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