What Is Geographic Atrophy?
An Advanced Form of Age-Related Macular Degeneration
Medically reviewed by Johnstone M. Kim, MD
Geographic atrophy is a common form of vision loss in older adults. It is an advanced form of age-related macular degeneration (AMD). It occurs as retinal cells in the macula—a film in the back of your eye—die off. Risk factors include being older than 60, a family history of the condition, and certain health conditions, including diabetes and heart disease. About 0.81% of the population of the United States has geographic atrophy in at least one eye, affecting 3.5% of those over age 75.
Geographic atrophy causes vision loss that gets worse over time. As the macula is affected, it causes dimness or spots in the center of what you see, while affecting how well you can see in low lighting. Currently, there are no treatments that cure geographic atrophy, though medical therapies can slow its progression and vision aids can help you navigate day-to-day life.
Types of Age-Related Macular Degeneration
There are two types of age-related macular degeneration that lead to geographic atrophy: wet and dry AMD. They differ based on the underlying cause and speed of onset of the vision loss.
Dry AMD
Dry AMD, the more common type, occurs due to the gradual thinning of the macula and the development of protein deposits called drusen. This type of vision loss progresses more gradually than wet AMD, going through three stages: early, intermediate, and late. While the early and intermediate stages may not cause symptoms, late dry AMD causes blurry areas or dark spots in your central vision.
Most cases of geographic atrophy are related to dry AMD, and having it raises the risk of wet AMD.
Wet AMD
Wet AMD, also known as advanced neovascular AMD, is macular degeneration due to the development of abnormal blood vessels in the macula. These vessels arise due to the protein, vascular endothelial growth factor (VEGF).
This type is always considered a late stage of AMD; it progresses very quickly and warrants immediate treatment. It's rarer, seen in about 20% of macular degeneration cases.
Geographic Atrophy Symptoms
Geographic atrophy typically affects one eye at a time, though those who have symptoms in one are more likely to develop it in the other. As an advanced form of AMD, geographic atrophy is a progressive type of vision loss, and it tends to get worse over time. This means you may not notice any vision changes in the early stages of this disease.
Your specific symptoms will depend on the regions of retinal cells that are affected by cell death. Your peripheral—or side—vision isn’t usually affected, but what you see in the center is. Over time, the changes to your vision become unmistakable and include:
Increasing need for brighter light when reading
Numbers or letters “disappearing” from your vision when reading
Trouble seeing in low or dim light
Progressive blurriness in the center of your vision
A dim or dark spot in the center of your vision
Dull or washed-out appearance to colors
In rare cases, the vision loss is more off to the side rather than central. In addition, advanced geographic atrophy, like other types of vision loss, can cause Charles Bonnet syndrome. This is characterized by complex visual hallucinations, such as seeing faces or objects that aren’t there.
These symptoms are your brain’s response to a lack of input due to vision loss. They’re unrelated to mental health conditions or neurological diseases like dementia and Alzheimer’s.
What Causes Geographic Atrophy?
The vision loss due to geographic atrophy occurs as photosensitive (light-sensitive) cells in the macula die off. The macula is the central part of the retina, the layer of cells associated with vision at the back of the eye. Typically, this impacts cells in the fovea, or central part of the macula, with the effects becoming more pronounced as the affected areas grow.
Researchers aren’t sure what sets off the age-related macular degeneration that causes geographic atrophy. Dry AMD has been linked to the development of calcium deposits, or drusen, in the macula, which hinders cell function. Wet AMD is a blood supply issue, arising due to the abnormal growth of blood vessels in the eye. This is caused by a protein called vascular endothelial growth factor (VEGF).
Risk Factors
A wide range of conditions and health factors can increase your risk of developing AMD and geographic atrophy. These include:
Family history of AMD
Having geographic atrophy in one eye
Age over 60
Smoking
Having lighter-colored eyes
Being post-menopausal without taking hormone replacement therapy
High blood pressure (hypertension)
Obesity
Excessive sun exposure to the eyes over the course of your life
Insufficient vitamins from vegetables and fruit in your diet
Diagnosis
The diagnosis of geographic atrophy involves a complete visual exam, additional visual tests and imaging techniques. In addition to taking your medical history, the optometrist (eye doctor) or ophthalmologist (specialty eye doctor) may perform the following tests:
Visual acuity: Assessing your central vision are tests of visual acuity, such as the one where you read letters from a chart across the room.
Dilated eye exam: After applying dilating drops to open your pupils, your provider looks for signs of damage inside the macula.
Amsler grid test: A test that can be performed at home, you look at a grid of vertical and horizontal lines to detect problems or changes in your central vision.
Visual function tests: Additional tests of vision can help your optometrist or ophthalmologist; one such test—microperimetry—combines imaging techniques to map the level of activity on the retina.
Fundus photography: Your provider uses highly sensitive cameras to take images of the retina to assess the scope and scale of damage to the retina.
Optical coherence tomography (OCT): Using X-rays, OCT creates three-dimensional computer models of your retina for analysis by your provider.
Fluorescein angiography: Most often used for wet AMD, a dye is injected into the bloodstream, which increases the contrast of images of blood flow in the retina to detect leaking or abnormalities.
Treatments for Geographic Atrophy
Until recently, there were no treatments approved by the FDA to treat geographic atrophy. The changes to your vision due to this condition are permanent. As such, therapy for geographic atrophy primarily focuses on monitoring and slowing the progression of the disease.
Izervay Injection
In August 2023, the FDA approved Izervay (avacincaptad pegol intravitreal solution) for treating geographic atrophy caused by AMD. Izervay was shown to reduce lesion growth associated with geography atropic by about 35%. It is administered once a month via eye injection for up to 12 months.
Syfovre Injection
A treatment that was approved by the FDA in February of 2023, injections of Syfovre (pergcetacoplan) may slow the progression of geographic atrophy due to AMD. You’ll need repeated injections, every 25 to 60 days.
Anti-VEGF Injection
If your geographic atrophy is caused by wet AMD, drugs that hinder VEGF function can stop bleeding or leaking from abnormal blood vessels. Providers deliver anti-VEGF injections directly into the eye while it’s numbed using a small, specialized needle. The effect is temporary, and you’ll need to come back in for multiple treatments.
Photodynamic Therapy
Sometimes used alongside anti-VEGF injections, this therapy relies on using a specialized laser beam to stimulate a medication called verteporfin in blood vessels in the retina. When activated by the laser, this medication—delivered via an injection in the arm—works to break down the blood vessels that are causing vision loss. This procedure is done with your eye numbed, and a special contact lens is used to direct the laser.
Vitamin Supplements
For geographic atrophy associated with dry AMD, taking vitamin supplements has been found to slow the progression of the disease. High daily doses of the following vitamin supplements may help:
Vitamin C, 500 milligrams (mg)
Vitamin E, 400 international units (IU)
Lutein, 10 mg
Zeaxanthin, 2 mg
Zinc, 80 mg
Copper, 2 mg
If you’re diagnosed, your provider will advise you on the proper dosages to take.
Prevention
Whether you’re at risk of developing geographic atrophy or have been diagnosed, there are several steps you can take to prevent or slow the progression of this condition. These prevention strategies include:
Regular check-ups: If you’ve been diagnosed with AMD, your healthcare provider will need to check your eyes regularly; geographic atrophy raises your risk of developing wet AMD.
Home monitoring: Keep track of your condition; your provider may recommend you use an Amsler grid daily on each eye to detect any changes to vision. Let them know if you notice any changes.
Dietary changes: Emphasize leafy greens, such as kale or spinach, alongside other fresh vegetables and fruit, and fish.
Eye protection: Wear sunglasses with UV protection to prevent sun exposure and protect the eyes.
Avoid smoking: Reducing the risk of developing AMD and geographic atrophy and slowing their progression are among the many benefits of not smoking.
Related: What You Need to Know About Quitting Smoking
Related Conditions
Several conditions are closely associated with geographic atrophy and can result from this condition. These include:
Blindness: AMD is the leading cause of blindness in adults over 60. As an advanced form of AMD, geographic atrophy can progress to permanent loss of central vision.
Depression: Losing the ability to see can have a significant impact on your mental health and quality of life, especially if you’re older than 65; up to 39% of those with AMD have clinical depression.
Anxiety: Anxiety disorders are about twice as likely to happen in those with vision loss compared to those with normal or correctable vision.
Living With Geographic Atrophy
If you have geographic atrophy, you’ll need to make accommodations for the loss of vision that results. As your optometrist or ophthalmologist will tell you, if you’ve been diagnosed with AMD or geographic atrophy, you’ll need eye exams every six months. You should also work with a low-vision specialist, who can help you develop strategies to adjust to your vision loss. These might include:
Using magnifying glasses for reading
Enlarging text on screens and devices
Reading large-print newspapers or books
Improving the lighting in your home or office
Using dictation software on your computer
Using programs or apps that offer voice-to-text or other assistive services
Since geographic atrophy can also severely impact your mental health, you may also want to seek out counseling services. In addition, support groups—both in-person and online—may help you cope with vision loss.
Alongside the approved medication Syfovre, several others are currently in development. Though geographic atrophy is challenging, treatment approaches to the condition continue to develop and improve.
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