Geographic atrophy (GA) is an advanced stage of age-related macular degeneration (AMD). It happens when the cells and blood vessels in an area of your retina break down and die. The area becomes thinned, which is called atrophy. This leads to permanent loss of vision in that area. You’re more likely to get GA if you’re over 60.
Here’s what to look for.
Signs and Symptoms of GA
GA creates blind spots in your central vision. That’s the space that’s right in front of you.
You may notice parts of objects that are directly in front of you look blurry. On the pages of a book, it may seem like certain letters are missing when you look straight at the page.
Other signs of GA include:
- Colors seem dull or washed out.
- A glare makes it harder to see.
- It’s harder to do things like cooking, crafts, driving, and reading.
- It’s harder to recognize people’s faces.
- It’s hard to tell the difference between different shades of colors.
- Objects look less clear or sharp.
- When lighting is dim, it’s harder to see.
- You have dark or dim spots in or near the center of your vision.
- You need extra lighting when you read.
At first, you may not notice any symptoms. But as GA develops, it spreads to other parts of your retina at the back of your eye. You may notice more vision changes over time.
You may have some vision loss, or you may have total vision loss. Total vision loss happens over time. It may take years to happen.
You may have GA in one eye or in both of your eyes. It may start in one eye, and then you may develop it in the other eye.
How to Find Out if It’s Geographic Atrophy
If you think you may have GA, talk to your doctor.
A doctor like an ophthalmologist, optometrist, or eye surgeon will give you a full eye exam and test for GA. They may take images of your retina.
Your doctor will look for changes in your macula, which is at the back of your eye. They’ll look for yellow deposits under your retina, which are called drusen. They’ll also look for a patch of your retina that’s missing the normal dark melanin pigment, which shows it’s GA.
At your exam, your doctor may:
- Test your vision. Your doctor will check how well you can see in your central vision. They may sit you in front of an eye chart and ask you to read it. They’ll check how clearly you see it. They may run similar tests to learn more about your vision loss. They’ll test both of your eyes.
- Give you a dilated eye exam. Your eye doctor will dilate your eyes. This means widening your pupils. They’ll use eyedrops to do it. It helps your doctor see the back of your eyes, which includes your retina and macula.
Your eye doctor may take images to detect GA, especially if you already have AMD.
Imaging may include:
- Fundus photographs. This is a picture of your retina. Your doctor may use it as a baseline for the amount of GA in your eye, so they can compare it with future images. They may use autofluorescence, which is special imaging that helps detect GA.
- Optical coherence tomography (OCT). This is an imaging test that shows a cross-section of your eye. It helps your doctor see if your macula has gotten thicker, if you’ve lost tissue, or if you have fluid under your retina. This can affect your vision.
- Fluorescein angiography. This is a test where your doctor injects dye into your arm. The dye lights up the blood vessels in your eye. Then they take photos of the back of your eye. Your doctor will look at the photos to see if you have new blood vessels in your macula. They’ll also see if the dye leaked anywhere, which shows there may be fluid in your retina or under it.
What You Can Do Now
If you have GA or if you have a risk of getting GA, there are some things you can do to take care of yourself. That includes watching for anything new that develops.
Make good lifestyle choices. What you eat and how active you are may affect how healthy your eyes are. Eat well by choosing a lot of fruits and vegetables. Dark green, leafy vegetables are a good choice. Stay active by exercising regularly. Talk to your doctor about an exercise program that’s safe to do with vision loss. Wear sunglasses to protect your eyes. If you smoke, quit.
See your doctor regularly. Starting when you’re 50 years old, see your doctor for a complete eye exam every year or two. Even if you don’t have vision loss, an eye doctor can look at your eye health and signs of issues. If you have vision loss, your eye doctor may recommend exams more often to see how you’re doing.
Amsler grid. This is a test that shows you if you have trouble seeing in your central field of vision. It shows a grid of straight horizontal and vertical lines. When you look at it, watch for any changes. Is it harder to read? Do you see wavy lines? Do you see broken lines? If you notice any of these things, talk to your eye doctor right away. You can do this test every day, for each eye.
At-home monitoring. Ask your doctor about home monitoring devices that help you keep an eye on your GA from home to see how it’s progressing.
Take vitamins. Your doctor may recommend certain vitamins to lower your risk of AMD. Don’t take any vitamins or supplements until you talk to your doctor.