Age-related macular degeneration

Age-related macular degeneration (AMD) is an eye condition that affects a tiny part of the retina at the back of your eye, which is called the macula. AMD causes problems with your central vision, but does not lead to total loss of sight and is not painful.

Age-related macular degeneration affects the vision you use when you're looking directly at something, for example when you're reading, looking at photos or watching television. AMD may make this central vision distorted or blurry and, over a period of time, it may cause a blank patch in the centre of your vision.

Causes

At the moment, the exact cause for AMD is not known. Some things are thought to increase chances of developing AMD:

• Age: Age-related macular degeneration develops as people grow older and is most often seen in people over the age of 65, although it can develop in people who are in their 40s and 50s.
• Gender: more women have AMD than men, probably because women tend to live longer than men.
• Genes: some genes have been identified which seem to be linked to the development of age-related macular degeneration in some people. This has been discovered by looking at families with more than one member who has AMD, but not all AMD is thought to be inherited.
• Smoking: smoking greatly increases your risk of developing AMD. Studies also show that stopping smoking can reduce your risk of developing AMD.
• Sunlight: some studies suggest that exposure to high levels of sunlight (particularly the UV light contained in sunlight) throughout your life may increase your risk of developing AMD. Wearing sunglasses to protect your eyes from the UV light in sunlight is a good idea for everyone throughout their life.
• Diet: a number of studies have looked at diet as a risk factor for someone developing AMD. At the moment there isn't agreement on how much of a risk factor diet is. There is some evidence that vitamins A, C and E and zinc may help to slow the progression of AMD in people who already have the condition.

Although you cannot change your age or genes, current thinking is that protecting your eyes from the sun, eating a balanced diet with plenty of fresh fruit and vegetables, and stopping smoking may all help to keep your eyes as healthy as possible.

Unfortunately, because the exact cause of AMD is not known you may develop this condition even if you don't have any of these risk factors.

Symptoms

Symptoms vary from person to person, but usually the first problems people notice are with their ability to see detail. You may have problems reading small print, even if you wear your usual reading glasses, or you may find that there is a slight smudge in your sight or that your vision has a small blurred area in the centre. Straight lines may look distorted or wavy or as if there's a little bump in them.

You may also find you become sensitive to bright light or that you see shapes and lights that aren't actually there. Sometimes people may only notice these changes in one eye.

You should have your eyes tested by an optometrist (optician) if:

• You notice any difficulty with reading small print with your reading glasses
• Straight lines start to look wavy or distorted
• Your vision isn't as clear as it used to be

The optometrist will be able to measure any changes in your vision and examine the back of your eye. If they detect any changes to your macula or any cause for concern they will arrange an appointment with the ophthalmologist for further tests

Source: Royal National Institute of Blind People (RNIB)