Understanding Retinal Disease and Protecting Your Vision
Understanding Retinal Disease
The retina works like the film in a camera. Light enters the eye through the pupil and lens, then lands on the retina. Specialized cells in the retina, called photoreceptors, detect light and color. These cells send signals through the optic nerve to the brain, where images are formed.
The macula is the central part of the retina. It is responsible for sharp, detailed vision. You rely on the macula for reading, driving, and recognizing faces. Many retinal diseases target the macula or the blood vessels that nourish the retina.
Several conditions fall under the category of retinal disease. Each one affects the retina in a different way, but all can threaten your vision if left untreated.
- Age-related macular degeneration (AMD): A condition that damages the macula, most common in adults over 50.
- Diabetic retinopathy: Damage to retinal blood vessels caused by high blood sugar in people with diabetes.
- Retinal vein occlusion (RVO): A blockage in the veins that carry blood away from the retina.
- Inherited retinal diseases: Genetic conditions such as retinitis pigmentosa that cause progressive vision loss.
- Retinal detachment: A medical emergency in which the retina separates from the back of the eye.
Many retinal diseases involve damage to blood vessels within or beneath the retina. In some conditions, blood vessels leak fluid into the retina, causing swelling that blurs vision. In others, the body grows fragile new blood vessels that are prone to bleeding.
A protein called vascular endothelial growth factor (VEGF) plays a central role in many of these problems. VEGF signals the body to grow new blood vessels. It also increases the leakiness of existing ones. This understanding has led to treatments that block VEGF and help preserve vision.
Who Is Affected and Risk Factors
AMD is the leading cause of vision loss among older Americans. An estimated many millions Americans were living with some form of AMD in 2019 (Prevent Blindness, VEHSS, 2019). This included 18.34 million with early AMD and 1.49 million with late-stage, vision-threatening AMD (Prevent Blindness, VEHSS, 2019). The risk of AMD increases significantly with age. More than 15 percent of white women older than 80 have advanced forms of AMD (NEI).
AMD has been found to be far more prevalent among white persons than among Black persons (NEI). Other risk factors include a family history of AMD, smoking, high blood pressure, and obesity.
Diabetic retinopathy is the most common cause of irreversible blindness in working-age Americans. In 2021, an estimated many millions people in the United States had diabetic retinopathy (JAMA Ophthalmology, 2023). That represents a prevalence rate of a substantial proportion among people with diabetes JAMA Ophthalmology, 2023). Having diabetes is the primary risk factor. The prevalence is lowest among people younger than 25 at a notable percentage and highest among the 65 to 79 age group at a substantial proportion (JAMA Ophthalmology, 2023).
Retinal vein occlusions occur when a blood clot blocks a vein in the retina. Risk factors include high blood pressure, diabetes, glaucoma, and blood clotting disorders. Among eyes examined in retina practices across the United States, a small percentage had branch retinal vein occlusion and a small percentage had central retinal vein occlusion (IRIS Registry, AAO, 2021).
Inherited retinal diseases are caused by gene mutations passed down through families. These conditions are less common but can cause severe vision loss, sometimes beginning in childhood or early adulthood.
Signs and Symptoms
Many retinal diseases affect the macula first. You may notice that straight lines appear wavy or distorted. A dark or blank spot may develop in the center of your vision. Colors may look faded or less vivid than before. These changes can happen gradually or suddenly.
Floaters are small spots, strings, or cobweb-like shapes that drift across your field of vision. A sudden increase in floaters can signal a retinal tear or detachment. Flashes of light, especially in your side vision, may also indicate that the retina is being pulled or torn.
If you experience a sudden increase in floaters, new flashes of light, or a shadow or curtain moving across your vision, see a retina specialist or go to the emergency room immediately. These symptoms may indicate a retinal detachment, which requires urgent treatment to protect remaining vision.
Blurry vision that comes and goes can be an early sign of diabetic retinopathy or macular edema (swelling of the macula). Some people notice that their vision is worse at certain times of day. Reading small print or seeing details at a distance may become more difficult.
Some retinal diseases cause no symptoms in their early stages. Early AMD and early diabetic retinopathy may not affect your vision at all until significant damage has occurred. This is why regular dilated eye exams are so important, especially if you are at higher risk.
Diagnosis and Testing
During a dilated eye exam, drops are placed in the eyes to widen the pupils. This allows a retina specialist to see the retina clearly. The specialist looks for signs of disease such as drusen (tiny yellow deposits under the retina), blood vessel changes, or fluid leakage. Dilated exams are the foundation of retinal disease screening.
Optical coherence tomography (OCT) is a non-invasive imaging test. It creates detailed cross-section pictures of the retina. OCT can detect swelling, fluid buildup, and thinning of the retinal layers. It is one of the most important tools for diagnosing and monitoring retinal diseases.
In fluorescein angiography, a special dye is injected into a vein in the arm. As the dye travels through the blood vessels in the retina, a camera takes rapid photographs. This test reveals leaking blood vessels, blockages, and areas of abnormal blood vessel growth. It helps guide treatment decisions.
Other tests may include OCT angiography (OCTA), which images blood flow in the retina without dye injection. Fundus photography captures high-resolution images of the retina's surface. Your retina specialist may also ask you to use an Amsler grid at home. This simple chart with a grid pattern helps you monitor for new distortion in your central vision between visits.
Treatment Options
Anti-VEGF therapy is the primary treatment for many retinal diseases. These include wet AMD, diabetic macular edema (DME), and retinal vein occlusion. The medications are delivered through intravitreal injections (injections directly into the eye). They work by blocking VEGF, reducing abnormal blood vessel growth and leakage.
Several anti-VEGF medications are available. Eylea (aflibercept) is one of the most commonly used, typically given every 4 to 8 weeks after an initial loading phase. Lucentis (ranibizumab) was the first anti-VEGF drug developed specifically for eye use and is given every 4 weeks. Avastin (bevacizumab) is FDA-approved for cancer treatment but is widely used off-label for retinal conditions, typically every 4 to 6 weeks.
Vabysmo (faricimab) was approved by the FDA in 2022 for wet AMD and DME. It is the first bispecific antibody for the eye, targeting both VEGF and angiopoietin-2. This second protein also contributes to blood vessel leakage. Vabysmo can be given every 4 to 16 weeks depending on treatment response.
Eylea HD (high-dose aflibercept) offers extended dosing intervals. The FDA has approved dosing intervals of up to 20 weeks for patients with wet AMD and DME who respond well after one year of treatment (FDA, 2024). Beovu (brolucizumab) is another option given every 8 to 12 weeks. It carries a risk of retinal vasculitis (inflammation of the retinal blood vessels) that must be monitored closely.
Dry AMD, the more common form, has historically had fewer treatment options. Two complement inhibitors are now approved specifically for geographic atrophy, an advanced form of dry AMD. Syfovre (pegcetacoplan), a complement inhibitor, and Izervay (avacincaptad pegol), also a complement inhibitor, work by slowing the progression of geographic atrophy. These are not used for wet AMD.
For people with intermediate dry AMD, the AREDS2 vitamin formula may slow progression to advanced AMD. This formula is a specific combination of vitamins C and E, zinc, copper, lutein, and zeaxanthin. A retina specialist can advise whether this supplement is appropriate for your situation.
For retinal vein occlusion and some cases of DME, steroid implants may be used. This applies when anti-VEGF therapy alone does not produce a sufficient response. Ozurdex (dexamethasone implant) is a long-acting steroid placed inside the eye that releases medication over several months. Iluvien (fluocinolone acetonide implant) is another option for chronic DME.
Laser photocoagulation (thermal laser treatment to seal leaking blood vessels) is still used in certain situations. It is particularly helpful for proliferative diabetic retinopathy. Laser treatment can help prevent further blood vessel growth and reduce the risk of severe vision loss.
Some retinal conditions require surgical intervention. Vitrectomy (a surgery to remove the gel inside the eye) may be needed for retinal detachment, severe vitreous hemorrhage (bleeding inside the eye), or macular holes. Scleral buckle surgery, in which a silicone band is placed around the eye, is another approach for retinal detachment. Pneumatic retinopexy uses a gas bubble injected into the eye to push the retina back into place.
What to Expect
Intravitreal injections are the most common retinal procedure. Before the injection, the eye is numbed with anesthetic drops. The skin around the eye is cleaned with an antiseptic solution. The medication is injected through the white part of the eye using a very fine needle. The entire process typically takes only a few minutes.
Most people feel pressure during the injection. Mild discomfort or a gritty sensation afterward is normal. Your retina specialist will monitor you briefly after the injection and provide instructions for care at home.
Retinal disease treatment often requires ongoing care. Anti-VEGF injections typically begin with a loading phase of monthly injections. After that, the schedule is based on how your eyes respond. Some patients need injections every month, while others can extend to every few months.
Regular follow-up appointments with OCT imaging help your retina specialist track the health of your retina. Adjustments to treatment are made as needed. Staying consistent with your treatment schedule is one of the most important steps you can take to protect your vision.
Living with Retinal Disease
For diabetic retinopathy, controlling blood sugar, blood pressure, and cholesterol is essential. Working closely with your primary care doctor or endocrinologist alongside your retina specialist gives you the best chance of slowing disease progression. For AMD, quitting smoking is one of the most impactful steps you can take to reduce your risk of progression.
If retinal disease has affected your central or peripheral vision, low vision aids can help you maintain independence. Magnifying devices, large-print materials, special lighting, and electronic reading tools can make daily tasks easier. A low vision rehabilitation specialist can assess your needs and recommend appropriate tools.
Living with a chronic eye condition can cause anxiety, frustration, or sadness. These feelings are common and understandable. Support groups, counseling, and connecting with others who share similar experiences can be helpful. Your retina specialist or primary care doctor can suggest resources in your area.
When to See a Retina Specialist
Adults over 50 should have regular dilated eye exams, even without symptoms. People with diabetes should have a dilated eye exam at least once a year. If you have a family history of AMD or other retinal diseases, discuss screening with your eye care provider. You may be referred to a retina specialist for further evaluation.
Certain symptoms require immediate attention. See a retina specialist or go to the emergency room right away if you experience any of the following.
- A sudden increase in floaters.
- New flashes of light, especially in your side vision.
- A dark curtain or shadow moving across part of your vision.
- Sudden loss of vision in one eye.
- Straight lines that suddenly appear wavy or distorted.
Questions and Answers
Not all retinal diseases can be prevented, but you can lower your risk. For AMD, not smoking, eating a diet rich in leafy greens and fish, exercising regularly, and managing blood pressure can help. For diabetic retinopathy, keeping blood sugar, blood pressure, and cholesterol under good control significantly reduces risk. Regular dilated eye exams help catch problems early, when treatment is most effective.
Intravitreal injections have a strong safety record. They are performed millions of times each year in the United States. As with any medical procedure, there are small risks, including infection, inflammation, and increased eye pressure. Serious complications are uncommon. Your retina specialist will explain the benefits and risks before starting treatment.
The length of treatment varies by condition and by individual. Some patients with wet AMD or DME require ongoing injections for years to maintain their vision. Others may be able to extend the time between injections as their condition stabilizes. Your retina specialist will tailor your treatment schedule based on how your retina responds at each visit.
Dry AMD is the more common form. It involves gradual thinning and breakdown of cells in the macula and may progress slowly over years. Wet AMD occurs when abnormal blood vessels grow beneath the retina and leak fluid or blood. This causes more rapid and severe vision loss. Dry AMD can progress to wet AMD over time. The treatments for each form are different. Anti-VEGF injections treat wet AMD. Complement inhibitors such as Syfovre (pegcetacoplan) and Izervay (avacincaptad pegol) are approved for geographic atrophy in advanced dry AMD.
Luxturna (voretigene neparvovec) is an FDA-approved gene therapy for a specific inherited retinal disease caused by mutations in the RPE65 gene. It is currently the only approved gene therapy for the eye. Additional gene therapies are in development. Gene therapy research for retinal diseases is an active and promising field, but most approaches are not yet widely available.