What Is Age-Related Macular Degeneration?
Age-related macular degeneration (AMD) is an eye disease that may get worse over time. It’s the leading cause of severe, permanent vision loss in people over 60 years old.
It happens when the small central portion of your retina, called the macula, wears down. The retina is the light-sensing nerve tissue at the back of your eye.
Because the disease happens as you get older, it’s often called age-related macular degeneration. It usually doesn’t cause blindness but might cause severe vision problems.
Another form of macular degeneration, called Stargardt disease or juvenile macular degeneration, affects children and young adults.
Wet vs. Dry Macular Degeneration
There are two main types of age-related macular degeneration:
Dry form. People with the most common type of AMD, called dry AMD, may have yellow deposits, called drusen, in their macula. A few small drusen may not cause changes in your vision. But as they get bigger and more numerous, they might dim or distort your vision, especially when you read.
The condition causes gradual vision loss, and as it gets worse, the light-sensitive cells in your macula get thinner and eventually die. In the atrophic form, you may have blind spots in the center of your vision. As that gets worse, you might lose central vision.
There are three stages of dry AMD: early, intermediate, and late. The disease usually gets worse slowly over the course of several years.
Some people start out with dry AMD and then develop wet AMD.
Wet form. This is a less common type of late-stage AMD. It tends to cause faster vision loss. Unstable blood vessels grow from underneath your macula. These blood vessels leak blood and fluid into your retina. Your vision is distorted so that straight lines look wavy. You may also have blind spots and loss of central vision. These blood vessels and their bleeding eventually form a scar, leading to permanent loss of central vision.
Most people with macular degeneration have the dry form, but it can lead to the wet form. Only about 10% of people with macular degeneration have the wet form.
If you have macular degeneration, you’ll need to see your eye doctor regularly and let them know whenever you notice changes in your vision.
Symptoms of Macular Degeneration
Early on, you might not have any noticeable signs of macular degeneration. It might not be diagnosed until it gets worse or affects both eyes.
Symptoms of macular degeneration may include:
- Worse or less clear vision. Your vision might be blurry, and it may be hard to read fine print or drive.
- Dark, blurry areas in the center of your vision
- Rarely, worse or different color perception
If you have any of these symptoms, go to an eye doctor as soon as possible.
Causes of Macular Degeneration
Age-related macular degeneration is more common in older people. It’s the leading cause of severe vision loss in adults over 60.
Macular degeneration may have something to do with your genes. If someone in your family has it, your risk might be higher.
Some other things that could raise your chances of getting it are:
- Smoking
- Having high blood pressure or high cholesterol
- Obesity
- Eating lots of saturated fat
- Being light-skinned
- Being female
How Is Macular Degeneration Diagnosed?
Your doctor can check you for age-related macular degeneration when you see them for a routine eye exam and have your eyes dilated.
They'll test your vision and also examine your retina – a layer of tissue at the back of your eye that processes light. They'll look for tiny yellow deposits called drusen under the retina. It's a common early sign of the disease.
Your doctor may also ask you to look at an Amsler grid – a pattern of straight lines that's like a checkerboard. If some of the lines appear wavy to you or some of them are missing, it could be a sign of macular degeneration.
If your doctor finds age-related macular degeneration, you may have a procedure called angiography or one called OCT. In angiography, your doctor injects dye into a vein in your arm. They take photographs as the dye flows through the blood vessels in your retina. If there are new vessels, or if vessels are leaking fluid or blood in your macula, the photos will show their exact location and type. OCT is able to see fluid or blood underneath your retina without dye.
It’s important to see your eye doctor regularly to find signs of macular degeneration early. Treatment can slow the condition or make it less severe.
What Treatments Are Available for Macular Degeneration?
There’s no cure for macular degeneration. Treatment may slow it down or keep you from losing too much of your vision.
Right now, there are no medicines or procedures for dry AMD. Instead, your eye doctor may recommend:
Diet changes. They may tell you to eat a balanced diet that’s rich in antioxidants and includes eye-friendly foods like dark leafy greens, yellow fruits and veggies, and fish.
Supplements. A large study by the National Eye Institute, called AREDS (Age-Related Eye Disease Study), found that a certain combination of vitamins and nutrients may protect the eyes in some people with intermediate or late-stage AMD. The supplements may slow intermediate AMD from becoming advanced and might help some people keep their sight longer, too. Researchers later tweaked the formula, giving it the name AREDS2.
If you have a lot of drusen in your eyes, your doctor might recommend you take AREDS2 supplements. If you’ve lost vision in one eye, the supplements may also lower your chances of getting wet AMD and vision loss in your other eye.
AREDS2 supplements are sold over the counter without a prescription. They are a combination of:
- Vitamin C (ascorbic acid)
- Vitamin E, lutein, zeaxanthin, and zinc (as zinc oxide)
- Copper (as cupric oxide)
These supplements don’t help everyone with dry AMD, though. Ask your eye doctor if they might be right for you. If your doctor gives you the green light, ask them to recommend a brand. Also ask your doctor to explain all the possible benefits and risks before you start taking the supplements. They may be part of some people’s treatment for wet AMD, too.
Low vision aids. These are devices that have special lenses or electronic systems to create larger images of nearby things. They help people who have vision loss from dry or wet macular degeneration make the most of their remaining vision.
If you have wet AMD, your treatment options might include:
Anti-angiogenesis drugs. These medications block the creation of blood vessels and leaking from the vessels in your eye that cause wet macular degeneration. The main protein causing that growth is called vascular endothelial growth factor (VEGF). VEGF inhibitors include: aflibercept (Eylea), bevacizumab (Avastin), pegaptanib (Macugen), and ranibizumab (Lucentis).
Inhibition of angiopoietin -2 (Ang-2), another protein involved in blood vessel formation, helps stabilize these fragile new blood vessels so they don't leak. It also makes vessels less sensitive to the effects of VEGF.
VEGF/Ang-2 inhibitors include:
Many people who’ve taken these drugs got back some vision that was lost. You might need to have this treatment multiple times.
Laser therapy. High-energy laser light can destroy abnormal blood vessels growing in your eye.
Photodynamic laser therapy. Your doctor injects a light-sensitive drug – verteporfin (Visudyne) – into your bloodstream, and it’s absorbed by the abnormal blood vessels. Your doctor then shines a laser into your eye to trigger the medication to damage those blood vessels.
Researchers are also studying new treatments for age-related macular degeneration, but they’re experimental. They include:
- Submacular surgery. This removes abnormal blood vessels or blood.
- Retinal translocation. This destroys abnormal blood vessels under the center of your macula, where your doctor can’t use a laser beam safely. In this procedure, your doctor rotates the center of your macula away from the abnormal blood vessels to a healthy area of your retina. This keeps you from having scar tissue and more damage to your retina. Then, your doctor uses a laser to treat the abnormal blood vessels.
Macular Degeneration Prevention
If you don’t have AMD, you can practice some healthy habits that may help you lower your chances of getting it:
- If you smoke, quit.
- Take charge of any other health conditions you have, like high blood pressure.
- Stay at a healthy weight and get regular exercise.
- Eat a balanced diet full of fruit, vegetables, and foods with omega-3 fatty acids (which are in certain fish and nuts).
Be aware that you can’t help prevent AMD by taking nutritional supplements, though.
What Is the Outlook for People With Macular Degeneration?
People rarely lose all of their vision from age-related macular degeneration. Their central vision might be bad, but they’re still able to do many normal daily activities. Usually, you're still able to use your peripheral vision.
The dry form of age-related macular degeneration tends to get worse slowly, so you can keep most of your vision.
The wet form of macular degeneration is a leading cause of permanent vision loss. If it’s in both of your eyes, it may affect your quality of life.
Wet macular degeneration can need repeated treatments. Test your vision regularly, and follow your doctor’s advice.