Age Related Macular Degeneration or AMD is a chronic, age-related, degenerative eye disease affecting the macula. People who suffer from macular degeneration lose their central vision as the macula becomes damaged through the progression of this disease.
In the eye, the macula is a small area in the centre of the retina, which is responsible for central vision. The macula allows a person to see details directly in front of them and allows them to do daily activities such as reading, driving, watching television, or recognizing people’s faces. Macular degeneration affects this portion of the vision.
The eye is often compared to a camera. The front of the eye contains a lens that focuses images on the back of the eye. This area is called the retina. The retina is covered with special nerve cells that react to light, just like the film in a camera.
These nerve cells are very close together in the middle of the retina where the eye focuses the images that we see. This part of the retina is called the macula.
There are two basic types of age related macular degeneration, dry AMD and wet AMD. The dry form of macular degeneration is more common, accounting for approximately 90 per cent of all cases. Generally, this version of the eye disease progresses more slowly than the wet variety. Both types of macular degeneration damage the macula and take away central vision.
Patients who suffer from macular degeneration rarely go completely blind. An individual diagnosed with this eye disease still have their peripheral vision.
The dry (atrophic) form of macular degeneration affects about 90 percent of those diagnosed and usually begins with the formation of tiny yellow deposits called drusen in the macula. Drusen usually do not cause serious loss of vision, but can cause distortion of vision. However, for reasons that are not yet understood, sometimes drusen will cause the macula to thin and break down, slowly leading to vision loss.
Wet (exudative) form of macular degeneration occurs in about 10 percent of those diagnosed. It is caused by the growth of abnormal blood vessels beneath the macula. These blood vessels can leak fluid and blood. Wet macular degeneration typically causes significant vision problems in the affected eye and can progress very rapidly, causing permanent central vision loss. “Blindness” can occur as rapidly as a few weeks to a few years with this variation of the eye disease.
The exact cause of age-related macular degeneration is not known. Some researchers feel that this eye disease may be hereditary, signalling an increased risk of being diagnosed with macular degeneration if someone in your family has or has had the eye disease. Other research has indicated that being a smoker and consuming too much red meat can contribute to increased risk of macular degeneration.
The video below shows how macular degeneration progresses in the eye and how things would appear to the person suffering from the eye disease.