What is AMD?
AMD is an eye disease that affects the macula – the central part of the retina at the back of the eye. The macula is full of light-sensitive cells that give us sharp central vision when we look straight ahead.
In AMD, the cells in the macula gradually break down. This can lead to blurred central vision, making it hard to read, drive and recognise faces. Peripheral, or side vision, is not affected in AMD.
AMD can be ‘early-stage’ or ‘late-stage’. There are two forms of late-stage AMD:
- Dry AMD – caused by a loss of cells in the macula. This mostly happens gradually but can sometimes be sudden.
- Wet AMD – caused by abnormal blood vessels that grow under the retina and bleed. It is often more sudden and noticeable than dry AMD.
Wet AMD can also develop if you already have the dry form of late AMD.
How common is AMD?
AMD is most common in people aged 50 years and older. One in seven Australians in this age group has the early signs of AMD. For the majority of these people it will not progress to serious vision loss.
AMD is the leading cause of legal blindness in Australia, responsible for 50 per cent of all cases. Nearly one in 15 Australians over the age of 80 has late-AMD.
What are the causes and risk factors?
The underlying causes of AMD are not yet known. But both genetic and lifestyle factors seem to play a role.
Factors that increase risk of developing the vision-threatening ‘late-stage AMD’ include:
- Family history of AMD
- Being over 50 years of age
- Having the early signs of AMD.
If you have any of these risk factors, it’s important to get your eyes checked regularly by an eye healthcare provider.
What are the signs and symptoms?
In its early stage, AMD may not have any noticeable symptoms but it can be detected with an eye exam. This is why it’s important to have regular eye tests, even if your vision hasn’t changed.
Signs of more advanced AMD include:
- Blurred vision
- Distorted vision, where straight lines appear wavy or bent
- Difficulties seeing when moving from light to dark settings
- Reduced vision when looking straight ahead, including problems with reading or recognising faces
- Dark patches in the centre of your vision.
You should never dismiss problems with your vision as just part of getting older. If you notice any sudden changes to your vision, see an eye healthcare provider.
How is AMD diagnosed?
To check for AMD, an optometrist or ophthalmologist will examine the back of your eye to see if there is waste buildup from the retina. This buildup forms yellow spots called drusen – an early sign of AMD.
If the early signs of AMD are found, you will need to have your eyes checked more than usual. That way, if the disease does progress to the ‘wet’ form of late AMD, steps can be taken straight away to help treat it and save your sight.
You can also check your vision at home with a simple test called an Amsler grid. Download an Amsler grid to print at home.
What treatment is available?
If the disease it in its early stages, your eye healthcare provider will check for any changes through regular eye tests. You can also use an Amsler grid to monitor your vision at home.
Your eye healthcare provider may also advise you to quit smoking or make changes to your diet to reduce your risk of the disease getting worse.
Wet AMD is often treated with injections into the eye. This does not cure the disease but can help stabilise and maintain the best vision for as long as possible. In some people, treatment can improve vision.
There is currently no approved treatment for the other form of late-stage AMD, dry AMD.
Can AMD be prevented?
You can’t change your family history or age. But it is possible to reduce your risk of AMD through a healthy lifestyle. This includes not smoking as well as eating plenty of fruits and vegetables, particularly dark leafy greens.
What AMD research is happening at CERA?
CERA’s Macular Research Unit aims to develop new treatments for AMD and prevent irreversible vision loss. In particular, our research focuses on ways to identify patients who are more likely to progress to later stages of AMD, the genetics of AMD, environmental associations with AMD, and biomarkers of AMD.
Professor Robyn Guymer heads up the Macular Research Unit and is a recognised world leader in research and clinical management of AMD. She led a world-first research trial at CERA looking at whether laser treatment can slow the progress of early-stage AMD.