1) WHAT EXACTLY IS AGE-RELATED MACULAR DEGENERATION (AMD)?
Age-related Macular Degeneration (AMD) is a debilitating visual disease affecting more people than glaucoma. With more than 100 million people worldwide suffering from AMD, it is a fairly common visual disease, but one that isn't yet as well known as some others. AMD affects four times more people than glaucoma and about half the number of those having cataracts. Older individuals are more likely to be symptomatic for AMD with over 25% of people 65+ having the disease; and this increasing to over 30% among those who are 70+.
AMD affects the center region of the retina, called the macula, and it is caused by the shutting-down and eventual death of the rod and cone cells in the central macular area. This part of the eye is responsible for our best vision including: fine detail, reading, facial recognition, contrast, depth perception, and color.
AMD is a significant and growing health problem: Roughly 16 million Europeans, 10 million Americans, and a total of over 110 million people world-wide have macular degeneration in some form.
According the the British Journal of Ophthalmology, these figures will double by 2050 because of the aging population.
According to the World Health Organization, AMD Causes $184 Billion in lost world productivity each year.
AMD has two basic forms: “Dry” AMD and “Wet” AMD. 90 percent of people with AMD have Dry AMD, or the “atrophic” form, for which there has been no treatment to restore vision yet approved in the marketplace. Dry AMD is literally the atrophication (or drying up) of the blood vessels nourishing the macula. It is accompanied by a loss of support cells, as well as a buildup of waste material called "drusen". Wet or “exudative” AMD is the more severe form of AMD. It happens after a patient has initially had some element of dry AMD. Wet AMD is caused by bleeding from new blood vessels building up under and within the retina that the body generates to compensate for the original blood vessels that have atrophied due to dry AMD. (This does not occur in all patients afflicted with dry AMD....just a percentage of them.) Wet AMD represents about 10 percent of all people with AMD. However, wet AMD is considered to be the most destructive and impairing of vision and can also cause the most rapid loss of vision.
2) WHAT ARE THE SYMPTOMS OF AMD?
AMD is a progressive disease and proceeds at a differing rate in each individual. There is no set standard for the progression. AMD causes a loss in vision that is usually gradual; it can lead to a lack of contrast sensitivity; it can cause visual distortion in the form of wavy vision; and it can lead to a loss of some, or all color vision. In the first phase of the disease, AMD generally will affect a person's finer detailed vision, including the ability to read fine print. As this disease progresses, a patient will begin to lose their central field of vision, which can impair their ability to do basic ordinary tasks such as cooking, getting dressed, driving an automobile, reading the paper, watching television, and sometimes even losing facial recognition. As the disease progresses, the damage caused by AMD in some patients, can lead to even a total loss of central vision. And, in the worst cases this can be overlaid with internal retinal bleeding, which further obstructs vision, as caused by the wet form of AMD.
3) HOW DO YOU GET AMD (Macular Degeneration)?
Macular degeneration is likely caused by a number of factors, but always with the result of damaging the blood vessels that nourish the retina. The macula is one of the most sensitive areas of the retina, so it is typically affected first when the blood circulation impairment begins. As the blood flow diminishes to the back of the eye, the rod and cone cells begin to shut down and stop the photo-processing of light into electrical signals relayed to the brain to permit vision.
The causes of AMD are many and varied. Heredity is a common cause; (if a close relative has experienced AMD, you are more likely to also experience it.) Other contributing factors include: excessive smoking, excessive drinking, diabetes, and excessive UV-light exposure, all of which can impair circulation to the retina. Even having blue eyes is a risk factor, with blue-eyed individuals having twice the likelihood of getting AMD as people with darker brown irises. This is because the blue iris lets more light into the back to the eye than a darker colored iris.