World Sight Day

World Sight Day is a global initiative providing an opportunity to raise the profile of the causes of blindness and vision impairment and the preventative measures. It takes place on the second Thursday in October every year.

Five main causes of blindness and vision impairment in Australia

Cataract

A cataract is a clouding of the eye's naturally clear lens. When the lens becomes opaque the amount of light that passes through it is reduced and scattered and the image cannot be correctly focused on the retina at the back of the eye, leading to blurred vision.

Symptoms include gradual and painless diminished or blurred vision, double vision in one eye and an increase in sensitivity to glare, especially when driving at night.

Vision with a cataract can be likened to looking through a dirty window. Changes in colour perception with yellowing of images may also be noticed.

Cataracts are mainly related to ageing. Long-term exposure to sunlight, smoking and heavy alcohol consumption may also increase the risk of developing cataracts and people with diabetes or vascular disease may also be at increased risk.

Cataracts are a leading cause of vision impairment in Australia. 31% of the population over the age of 55 has cataract.

For more information visit The Royal Australian and New Zealand College of Ophthalmologists website at www.ranzco.edu.

Glaucoma

Glaucoma is the name given to a group of eye diseases where the optic nerve at the back of the eye is slowly destroyed. In most people this damage is due to an increased pressure inside the eye, but people with normal or low pressure can still develop glaucoma.

Glaucoma leads to the loss of peripheral vision and in severe cases can cause tunnel vision and eventual blindness.

It is estimated that about half of all people who have glaucoma don't know they have it. Most people remain undiagnosed until they notice a deterioration in their vision. Once this vision is lost it cannot be restored.

Early diagnosis and treatment of glaucoma is essential to control the condition and protect sight.

People over the age of 40 are more likely to develop glaucoma than young people. 300,000 Australians have glaucoma and this is set to increase as the population ages.

For more information visit www.glaucoma.org.au

Diabetic retinopathy

Diabetic retinopathy is an eye disease caused by diabetes. Diabetes damages the blood vessels that nourish the retina, the seeing part of the eye.

Early diagnosis and intervention followed by regular eye checks??? are critical to good eye health. Although sight threatening complications can occur, treatments are effective and vision can be preserved.

People who have diabetes can reduce their risk of developing diabetic retinopathy by keeping their blood sugar levels even and maintaining an active and healthy lifestyle.

As Type 1 diabetes is genetic, people with a family history of diabetes you should have their eyes tested.

With early detection 98% of vision loss from this disease can be prevented.

For more information on how diabetes can affect an individual's vision visit the Diabetes Australia website in your state.

• ACT
• New South Wales
• Northern Territory
• Queensland
• South Australia
• Tasmania
• Victoria
• Western Australia

Macular Degeneration

Affecting mainly adults, Macular Degeneration is the leading cause of blindness and severe vision loss in Australia.

The macula is the light sensitive tissue at the back of the eye. Macular Degeneration causes progressive loss of central vision which enables people to see fine details, to read or to recognise faces.. Peripheral vision is not affected.

The onset of Macular Degeneration can be sudden and dramatic. There is presently no cure however current treatment aims to keep vision for as long as possible and in some cases may provide vision improvement. Early detection is vital in saving sight.

Risk factors include age, smoking and a family history of Macular Degeneration.

Macular Degeneration affects one in seven Australians over the age of 50 and its incidence increases with age.

For more information visit the Macular Degeneration Foundation's website at www.mdfoundation.com.au

Refractive error

Refractive errors are defects to the eye that result in light not being properly focused on the eye's retina. The most common refractive errors are hypermetropia (long-sightedness), myopia (short-sightedness), astigmatism (uneven focus) and presbyopia (an age-related problem with near focus).

With the exception of presbyopia, refractive errors usually develop during childhood when the eyes are growing.

Although long-sightedness and short-sightedness are not specifically age-related, they remain common conditions in later life.

It is estimated that nearly 300,000 Australians are vision impaired because of under-corrected refractive error.

For more information on refractive error visit the website of the Optometrist Association Australia at www.optometrists.asn.au.