Proliferative Diabetic Retinopathy: Protecting Your Vision

Diabetic retinopathy is one of the most common causes of permanent vision loss in working-age adults. After 20 years of living with diabetes, the vast majority of people with type 1 diabetes and a significant portion of those with type 2 diabetes will have developed some degree of retinopathy. PDR is uncommon in the first decade after a type 1 diabetes diagnosis, but its prevalence rises meaningfully after 15 years.

The duration of diabetes is one of the strongest predictors of PDR. In people with type 1 diabetes, retinopathy of some kind begins appearing in about a quarter of patients after 5 years, reaches roughly 60 percent by 10 years, and climbs to around 80 percent by 15 years. The chance of progressing to the proliferative stage increases steadily with each additional year.

Poorly controlled blood sugar is the most significant modifiable risk factor for developing PDR. Other conditions and lifestyle factors can compound this risk.

• High blood pressure (hypertension)
• High cholesterol
• Kidney disease related to diabetes
• Pregnancy in women with pre-existing diabetes
• Smoking

Managing these factors alongside blood sugar control can meaningfully reduce the risk of progression.

Anti-VEGF medications block the protein (vascular endothelial growth factor) that drives abnormal blood vessel growth and leakage. They are delivered as intravitreal injections, meaning the medication is injected directly into the vitreous cavity of the eye. This has become a primary treatment approach for PDR.

Commonly used anti-VEGF medications include aflibercept (Eylea), ranibizumab (Lucentis), bevacizumab (Avastin), and faricimab (Vabysmo). Bevacizumab is FDA-approved for cancer treatment and is used off-label in the eye. Injections may be needed as frequently as every 4 to 8 weeks in the early stages, with the schedule adjusted over time based on response. High-dose aflibercept (Eylea HD) has received FDA approval for extended dosing intervals, which may reduce the number of office visits for some patients.

Panretinal photocoagulation, also called PRP or scatter laser treatment, has been a trusted treatment for PDR for decades. During this procedure, a specialist applies hundreds to thousands of small laser burns across the peripheral (outer) areas of the retina. This reduces the retina's oxygen demand and decreases the signals that drive abnormal vessel growth.

PRP is not designed to improve vision. Its goal is to stop further vision loss by stabilizing or causing the abnormal vessels to shrink. Possible side effects include some reduction in peripheral vision and decreased night vision. These trade-offs are generally considered acceptable when weighed against the risk of severe vision loss from untreated PDR. PRP is sometimes combined with anti-VEGF injections for a more comprehensive result.

When diabetic macular edema (swelling in the central retina) accompanies PDR, or when the eye does not respond adequately to anti-VEGF therapy, steroid injections may be considered. Options include triamcinolone acetonide and dexamethasone implant (Ozurdex), a small sustained-release device placed inside the eye that delivers medication over several months.

Vitrectomy is a surgical procedure in which the vitreous gel is removed from inside the eye. It may be recommended when a vitreous hemorrhage does not clear on its own within a reasonable period, or when scar tissue causes a tractional retinal detachment. During the surgery, the blood-filled vitreous is removed and replaced with a clear solution. Laser treatment is often applied at the same time. In some cases, a gas bubble or silicone oil is placed inside the eye to help hold the retina in place while it heals.

The landscape of PDR treatment has shifted considerably in recent years. Intravitreal injections have become more common as an initial treatment than laser alone, reflecting strong clinical evidence supporting their effectiveness. Research comparing anti-VEGF therapy directly to laser has shown that injections can produce vision outcomes at least as good as traditional laser treatment, and in some cases better. Combination approaches and newer medications with longer-lasting effects are continuing to expand the options available to patients.

PDR cannot be fully reversed once it has developed, but that does not mean treatment is futile. Anti-VEGF injections, laser, and vitrectomy can stop the disease from progressing and in some cases lead to meaningful improvements in vision, particularly when bleeding clears or swelling is reduced. The damage that has already occurred to the retina may be permanent, which is precisely why early detection matters so much. Catching PDR before major complications develop gives treatment its best chance to preserve the vision you have.

There is no single answer because the number depends on how your eye responds, how active the disease is, and which medication is used. In the early phase of treatment, injections are often given every 4 to 8 weeks. Over time, the interval may be extended if the disease is well controlled. Some patients are able to taper to fewer visits per year, while others need ongoing treatment to maintain stability. Newer medications with extended dosing options may reduce the total number of injections needed for some patients.

Physical activity is generally beneficial for diabetes management and overall health, but certain types of exercise may need to be modified when PDR is active. Heavy straining, very high-intensity exertion, or activities involving jarring impact can theoretically raise the risk of bleeding inside the eye. This does not mean you should stop moving. Rather, it is worth discussing your specific exercise habits with both your diabetes care team and your retina specialist, who can offer guidance based on the current state of your eye health.

Not everyone with PDR loses significant vision. Many patients who receive timely treatment and manage their diabetes carefully maintain useful vision for years. However, the risk of serious vision loss is real, particularly when PDR is left untreated or when complications such as retinal detachment occur. The most effective protection is a combination of consistent medical treatment, good blood sugar control, and keeping every recommended eye appointment. These steps together give you the best chance of preserving your sight.

These are two different complications of diabetic eye disease that can occur independently or together. PDR refers specifically to the growth of abnormal new blood vessels on the retinal surface, which is what creates the risk of bleeding and retinal detachment. Diabetic macular edema (DME) is swelling in the macula, the central part of the retina responsible for sharp, detailed vision. DME can affect central vision directly and is treated somewhat differently, though anti-VEGF injections are used for both conditions. Your specialist will evaluate whether one or both are present and tailor your treatment plan accordingly.

The rate of progression varies from person to person and is closely tied to how well blood sugar and blood pressure are managed. In some individuals, PDR can remain relatively stable for a period of time, while in others it may worsen rapidly. Complications such as vitreous hemorrhage or retinal detachment can occur suddenly and without warning, which is why waiting to seek care is never advisable. Regular monitoring is the only way to know whether the disease is stable or advancing, and to intervene before irreversible damage occurs.