Of all the eye health conditions we develop as we get older, macular degeneration is the most common, affecting 1.75 million Americans over the age of 65. That number is expected to grow to a staggering three million by 2020.
Macular degeneration is caused by damage to the macula, a small spot near the center of the retina, which is the part of the eye that’s responsible for sharp, focused vision. The rate of this disorder’s progression really depends on the patient. For some people, it can progress slowly, while for others, it can get worse faster. The most common symptom of macular degeneration is blurry vision, specifically a blurred spot near the central line of vision. Over time, that spot may grow larger or blank spots may develop in your central vision. It may also lead to a decrease in the brightness of objects.
While macular degeneration does not usually lead to blindness, the deteriorating quality of eye health and the loss of central vision can have a negative impact on the patient’s life, as they won’t be able to participate in activities they used to enjoy, such as reading, writing, driving, and even cooking.
Types of Macular Degeneration
There are two different kinds of macular degeneration; dry macular degeneration and wet macular degeneration. Dry macular degeneration is the most commonly seen as the first stage of the disorder. As we age, macular tissues thin or pigment is deposited in the macula. It may also be a combination of the two. In either case, it can lead to blurry vision. One of the early signs of dry macular degeneration is yellowish spots, known as drusen, accumulating around the macula. Of the two types of macular degeneration, this is the less severe.
Wet macular degeneration is more serious. It is caused by new blood vessels that grow beneath the retina, forcing it to leak blood and fluid, and causing permanent damage to retinal cells. In some cases, known as occult macular degeneration, the new blood vessel growth beneath the retina is not as pronounced.
Risk Factors for Macular Degeneration
If you smoke or have a family history of macular degeneration, then it’s important that you go for regular eye health exams, as you’re more likely to develop macular degeneration as you age. Be sure to let your optometrist know if you have any vision problems, especially if they persist or get worse.
Other risk factors for macular degeneration include obesity and high blood pressure. There are even a couple surprising causes. People with light colored eyes are more likely to develop macular degeneration. Some drugs’ side effects can also cause the disorder.
One big way to maintain healthy vision and avoid developing macular degeneration is wear protective eyewear when you’re out in the sun. UV damage from the sun is one of the biggest contributing factors to macular degeneration, so be sure to purchase a pair of sunglasses that are enforced with extra UV protection.
Testing for Macular Degeneration
To test for macular generation, your optometrist will often perform a simple test using the Amsler Grid to measure how your central vision is performing. You will be asked to focus on a dot in the center of the grid. If you suffer from macular degeneration, the lines will appear to be wavy and the dot will look blurry. You can actually find a version of the Amsler Grid online to test your vision and eye health in-between checkups.
Optometrists can also perform more in-depth eye health exams to check for macular degeneration, like using drops to dilate your pupils and then looking at the back of your eyes to check for drusen spots. Your doctor may also check for macular degeneration by injecting a colored dye into a vein—the harmless dye will travel through your body and highlight the various blood vessels in your eyes—and then use a special camera to check for abnormalities. This test is especially useful for wet macular degeneration, because it will show if there is any retinal cell damage.
“Dry macular degeneration,” Mayo Clinic web site; http://www.mayoclinic.com/health/macular-degeneration/DS00284/DSECTION=tests-and-diagnosis, last accessed December 20, 2013.
Haddrill, M., “Age-Related Macular Degeneration,” All About Vision web site, August 23, 2013; http://www.allaboutvision.com/conditions/amd.htm.
“Facts About Age-Related Macular Degeneration,” National Eye Institute web site; http://www.nei.nih.gov/health/maculardegen/armd_facts.asp, last accessed December 20, 2013.