Age Related Macular Degeneration
What is AMD?
Age related macular degeneration is a common eye condition that usually affects those of us over the age of 50. It affects the centre part of the retina which is referred to as the macular.
The retina is a thin layer of skin that covers the back of the eye. It is covered with cells that are sensitive to light and are called photoreceptors.
These photoreceptors are divided into 2 categories.
Rods look after our peripheral vision and also contrast colours, whereas the cones look after central and colour vision along with clarity.
The Macular is a 5mm wide section of the retina which is covered in cones and is therefore very important to the majority of our vision. The condition doesn’t cause pain or total loss in the vision, however, when looking directly at something such as the television or a photograph you may notice a blank patch in the centre of your vision.
There is no exact known reason as to why the condition is developed but risk factors include:
- high blood pressure
- being overweight
- having a family history of AMD.
Types of AMD
There are two types of age related macular degeneration:
1. Dry AMD – this develops slowly and causes gradual changes to your central vision
2. Wet AMD – this can develop very quickly, resulting in significant changes to your central vision over weeks or even days
AMD affects people in different ways. Symptoms may develop slowly if you have dry AMD, especially if it’s only in one eye. However, as the condition progresses, your ability to see clearly will change.
- Gaps or dark spots (like a smudge on glasses) may appear in your vision, especially first thing in the morning
- Objects in front of you might change shape, size or colour or seem to move or disappear
- Colours can fade
- You may find bright light glaring and uncomfortable or find it difficult to adapt when moving from dark to light environments
- Words might disappear when you are reading
- Straight lines such as door frames and lampposts may appear distorted or bent
Unfortunately there are no known treatments for Dry AMD but certain visual aids can help.
If you have Wet AMD then you may be given injections into the eye and, very occasionally, a light treatment called “photodynamic therapy” to stop your vision getting worse.