Cataracts aside, by far the most common eye degeneration is “age-related macular degeneration” (ARMD) which accounts for almost 50% of all visual impairment in the developed world. It usually affects people over 60 years of age.
What and where is the macula?
At the back of the eye is the retina, which is made up of millions of tiny cells which all play a role in converting light rays into electrical signals, which the brain then interprets as vision. The retina can be likened to the film in a camera. The area encompassing the centre point of the retina is the macula which is very important and is responsible for what we see when we look straight ahead. It allows us to see fine detail and colour and is particularly important for reading/near vision. Unfortunately this is the bit of the eye most affected by ageing. Some risk factors are a family history of ARMD, smoking, raised blood fat levels and excess UV light exposure.
Broadly speaking, there are two types of ARMD, usually referred to as “wet” and “dry”. This does not describe wet or dry eyes, it simply refers to whether the degeneration has leaky blood vessels in it or not. Only your ophthalmologist can determine this. If these blood vessels are present then they can bleed or leak fluid into the macula. Both of these situations tend to cause fairly rapid deterioration of sight. It is however, much more common to have the dry type than the wet type.
What are the symptoms?
In the early stages central vision may appear blurred or slightly distorted. This usually develops gradually over a period of many months or years. Unfortunately in some people the degeneration worsens as they get older and the central sight slowly continues to decline. Sometimes, however, the eyesight may suddenly worsen with an increase in distortion and this may indicate a transition to the “wet” or leaky type of degeneration.
So, what can be done?
For most people with mild degeneration there is nothing specific that can be done to reverse the aging but basic low vision techniques such as good lighting and magnifiers can prove very successful to maximise the vision. It may be advisable to take special formulated eye vitamins for dry ARMD. For some people with wet degeneration that has been caught early it may be possible to apply some laser to the back of the eye to prevent further degeneration. In addition some novel new therapies are becoming available for wet ARMD. Please look out for the next in this informative series and remember to contact your ophthalmologist if you need any further advice.