Geographic atrophy is a type of vision loss that many older adults experience. It represents an advanced stage of age-related macular degeneration (AMD), where the retinal cells in your macula—located at the back of your eye—start to deteriorate. Common risk factors include being over 60, having family members with the condition, and certain health issues like diabetes and heart disease.
In the U.S., about 0.81% of people have geographic atrophy in at least one eye, with the numbers jumping to 3.5% for those over 75. This condition causes vision to deteriorate gradually, leading to dim or spotty central vision and making it hard to see well in dim light. Although there’s no cure yet, some medical treatments can slow its progression, and vision aids can help you handle daily tasks.
There are two main types of AMD that can lead to geographic atrophy: wet and dry. Dry AMD, which is more common, results from the slow thinning of the macula and the buildup of protein deposits called drusen. It advances slowly, moving through three stages: early, intermediate, and late. While early stages might not cause noticeable symptoms, late dry AMD can lead to blurred central vision or dark spots. Most geographic atrophy cases relate to dry AMD, but having it can increase the risk of developing wet AMD.
Wet AMD, also known as advanced neovascular AMD, involves abnormal blood vessel growth in the macula due to a protein called VEGF. This type progresses fast, requires immediate treatment, and affects about 20% of those with macular degeneration. Geographic atrophy often starts in one eye, but if you have symptoms in one eye, it’s likely the other will eventually be affected too.
As an advanced form of AMD, geographic atrophy is progressive and usually worsens over time. In its early stages, you might not notice any changes to your vision. The symptoms you experience depend on which retinal cells are impacted. While peripheral vision typically remains unaffected, central vision does change, often unmistakably, over time. Rarely, the vision loss can occur more to the side than in the center. Additionally, advanced geographic atrophy, like other forms of vision loss, might lead to Charles Bonnet syndrome, causing complex visual hallucinations. These are not linked to mental health issues or conditions like dementia.
Vision loss in geographic atrophy happens as light-sensitive cells in the macula die off. These changes are more obvious as the affected areas increase. The exact cause of AMD leading to geographic atrophy isn’t well understood. Dry AMD is linked to calcium deposits in the macula, which affect cell function, while wet AMD stems from abnormal blood vessel growth due to the VEGF protein.
Your risk of AMD and geographic atrophy can increase with various conditions and health factors. Diagnosing geographic atrophy involves a comprehensive eye exam, additional visual tests, and imaging techniques. Your eye doctor will also consider your medical history and may perform several tests.
Only recently have treatments been approved by the FDA for geographic atrophy. The changes in vision it causes are permanent, so therapies mainly focus on monitoring and slowing the disease’s progression. In August 2023, the FDA approved Izervay, a treatment shown to reduce lesion growth by 35%, given through monthly eye injections for up to a year. Another treatment, approved in February 2023, involves Syfovre injections to slow geographic atrophy, requiring doses every 25 to 60 days.
If your condition is due to wet AMD, medications that block VEGF can help stop bleeding from abnormal vessels. These anti-VEGF injections go directly into the eye, numbed beforehand, but you’ll need repeated treatments for lasting effects. Additionally, a specialized laser treatment using verteporfin can assist in breaking down troublesome blood vessels, paired with anti-VEGF injections. This procedure is done with the eye numbed, using a special contact lens to guide the laser.
For geographic atrophy from dry AMD, certain vitamin supplements might slow disease progression. Your doctor will advise on appropriate dosages. If you’re at risk or have been diagnosed, several steps can help prevent or reduce the rate at which the condition progresses.
If you have geographic atrophy, you’ll need to adjust for vision loss. Your optometrist or ophthalmologist will recommend eye exams every six months. Working with a low-vision specialist can help you develop strategies to manage these changes. Since geographic atrophy can impact mental health, counseling and support groups may be beneficial. Alongside the current treatment options, new medications are being developed, aiming to improve outcomes for those with this challenging condition.
