Next month is AMD awareness month once more, a chance to further advance research and awareness into this increasingly common condition. What areas of AMD do you need to focus on, as an ophthalmologist?
Causes of AMD
There are many causes of AMD, some modifiable and some non modifiable risk factors. These include:
- Family history
- Low macular pigment density
- Smoking
- High cholesterol / poor diet
- UV / sun exposure
Age, as the name suggests, is also a factor, but we should be aware of the risks of developing AMD whatever age we are. The condition usually presents itself in old age, usually from the age of 60, but your life before can affect whether you develop it.
Patients should be advised to have regular eye examinations as well as paying attention to their overall health – eating plenty of leafy green vegetables, cutting down on alcohol, quitting smoking and doing more exercise.
Family history is obviously an unavoidable risk factor but you can minimise risks of developing AMD by maintaining a healthy lifestyle.
Signs and symptoms
Regular eye examinations will monitoring macular pigment levels, and if the MPOD (macular pigment optical density) is low then you can put in place measures to treat the patient. Once the condition becomes more advanced the patient will notice these common signs:
- Blurred / blind spot in the centre of the eye
- Inability to read in anything but bright light
- Difficulty reading printed text
- Colours seem dull
- Hazy vision
- Difficulty recognising faces
Dry AMD and Wet AMD
Dry AMD is what first develops, over a number of years, and gradually deteriorates a central vision, but does not affect your peripheral vision. Around 10-15 per cent of people who have dry AMD then go on to develop Wet AMD. It develops more quickly than the dry form and leads to total blindness. It is caused by blood vessels developing when the macular stops working, except they are not in the right place and cause the macular to swell and bleed. This is sometimes referred to as ‘leaky blood vessels’ and also why it is defined as wet.
Treatments available
As yet there are no treatments to improve Dry AMD, only to stop it developing to wet AMD. Anti-VEGF (anti-vascular endothelial growth factor) drugs limit the growth of the leaky blood vessels that lead to wet AMD. The treatment is painful, with the drugs being injected directly into the eye.
If dry AMD signs are caught early, through macular pigment screening, then the ophthalmologist can slow progress with lutein and zeaxanthin supplementation. Studies have shown it can slow the progression of AMD, and potentially remove or delay the need for painful anti-VEGF treatment.
Screening for all
The main message for AMD, and many other eye conditions, is that patients need to know the important of eye examinations. They should attend regularly depending on their age, so that any conditions can be caught early. The key is early intervention and regular monitoring to save as much sight as possible.
Find out more about AMD awareness month on the MacuHealth website and access resources on AMD from the RNIB site.