Age-related macular degeneration (AMD) is the loss of vision in the centre of the eye and is caused by the sun’s high-energy, blue light damaging the retinal protective shield, or macula, over time. As the disease progresses, it blurs the patient's central vision – creating the illusion of a ‘hole’ so that they can see a person’s hair and clothes but not their face.
The macula is the small area at the centre of the retina responsible for central vision. Its role is to filter out harmful blue light before it hits the sensitive rods and cones on the retina. As a person gets older, the risk of AMD increases, particularly when coupled with poor diet, smoking and drinking which can accelerate the onset of the disease.
AMD can take two forms, wet and dry. Wet AMD is caused by the abnormal growth of blood vessels under the macula. This leads to rapid loss of central vision. Wet AMD is considered to be advanced AMD and is more severe than the dry form. Dry AMD, the more common form, occurs when the light-sensitive cells in the macula slowly break down. Untreated dry AMD can progress into wet AMD.
According to the National Eye Institute (NEI) at the US National Institutes of Health (NIH), nearly two million Americans have vision loss from advanced AMD, and another seven million with AMD are at substantial risk for vision loss. It is thought that the AREDS vitamin and mineral formulation could save more than 300,000 people from vision loss over the next five years.
For more information, visit the NEI Website at http://www.nei.nih.gov/.