Proliferative diabetic retinopathy (PDR) is the advanced stage of diabetic retinopathy. It involves the development of abnormal retinal blood vessels. The vessels may leak blood and fluid into the retina and neighboring structures, leading to vision loss.

Diabetic retinopathy is a potential complication that develops due to diabetes. If a person’s blood sugar levels become too high, it can damage the retinal blood vessels.

When the blood vessels are damaged, the retina does not get enough fresh oxygen. Over time, the retina may grow new blood vessels. A person’s risk of developing diabetic retinopathy increases the longer they have diabetes.

When a person has diabetic retinopathy, the new, abnormal blood vessels in the retina may bleed or leak into the vitreous, the clear gel between the lens and the retina. This may cause the retina to swell.

Doctors classify diabetic retinopathy by stage. PDR is the advanced stage of the condition. The condition may progress and lead to vision loss if left untreated. Diabetic retinopathy is the leading cause of vision loss in adults between 20–74 years of age.

This article examines PDR, including its symptoms and treatment options.

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PDR refers to the final and more advanced stage of diabetic retinopathy. Doctors refer to the earlier stages of diabetic retinopathy as nonproliferative. The term proliferative describes the growth of new blood vessels that can lead to complications with vision and eye health.

As diabetic retinopathy progresses, circulation problems with blood vessels begin to deprive the retina of oxygen. This causes damage to the retina and results in the development of new, fragile blood vessels. Health experts refer to the growth of new abnormal blood vessels as neovascularization.

These new blood vessels may begin to grow in the retina and into the vitreous, the gel-like fluid that fills the back of the eye. The abnormal blood vessels are fragile and may bleed into the vitreous and form scar tissue. All of these changes in the vessels can affect vision.

Click here to learn more about the stages of diabetic retinopathy.

Nonproliferative diabetic retinopathy (NPDR) describes the earlier stages of the condition and differs from PDR.

During these earlier stages, symptoms are usually mild or nonexistent. Chronically high blood sugar levels cause changes that weaken the blood vessels in the eye and throughout the body. This results in swelling and the development of tiny bulges in the blood vessels, known as microaneurysms.

However, this stage does not yet involve the growth of new blood vessels.

Click here to learn more about the differences between NPDR and PDR.

When diabetic retinopathy has advanced to PDR, a person will likely experience symptoms. Typically, symptoms include:

  • blurred vision
  • having fluctuating vision, which may include vision that changes from blurry to clear and back
  • seeing increasing numbers of floaters, which may appear as gray or black specs or strings

During this stage of the condition, a person may also experience diabetic macular edema. This describes swelling of the macula of the eye. This is part of the retina that is responsible for central vision, color vision, and fine detail.

In the most advanced instances of PDR, irreversible blindness may occur.

Learn about the legal definition of blindness.

Diabetic retinopathy is easier to treat in the earlier stages before it can cause permanent damage. As such, it is essential that people attend yearly eye exams, where an eye doctor can identify the condition. Treatment for PDR is essential to preserve vision loss. Treatment options may include:

Managing blood sugars

Controlling blood sugar levels and managing diabetes is one of the key components of treating PDR. Good diabetes management includes:

Learn all about blood glucose levels.


The cells in the body produce vascular endothelial growth factor (VEGF), which helps produce new vessels. Some people with diabetic retinopathy produce too much VEGF. Anti-VEGF is a medication used to block VEGF and prevents the growth of new abnormal blood vessels.

Doctors administer the medication through a series of painless injections into the eyes. Anti-VEGF may also help decrease swelling in the macula.

Learn more about VEGF injections.

Laser treatment

Different types of laser treatment may also help treat PDR. For example, laser procedures may seal leaking blood vessels and decrease swelling of the retina.

Learn more about laser treatment for diabetic retinopathy.


In some cases, doctors need to perform surgery, known as a vitrectomy, to clear blood from the vitreous. Surgery to repair a retinal detachment is also an option.

Learn more about a vitrectomy for diabetic retinopathy.

PDR can also lead to complications and other eye diseases, including:

Diabetic macular edema (DME)

DME occurs when the blood vessels leak fluid into the macula. The macula is part of the retina that allows for central vision. If this occurs, it can lead to problems with vision, including blurry vision. About 1 in 15 people with diabetes eventually develop DME.

Neovascular glaucoma

The growth of abnormal blood vessels can block the flow of fluid out of the eye. This may lead to a buildup of eye pressure and the development of a subtype of glaucoma.

Tractional retinal detachment

This occurs when the retina pulls away from its usual position. It develops when scar tissue pulls the retina away from the back of the eye. Complications from diabetes, including PDR, are the most common cause of tractional retinal detachment.

Learn all about other eye conditions.

PDR is the advanced stage of diabetic retinopathy. It develops due to continued high blood sugar levels damaging blood vessels in the retina. The distinguishing feature of PDR is the development of new, fragile blood vessels that may leak or form scar tissue.

If not treated promptly, it can lead to blindness. Treatment, including medical injections, laser treatment, and surgery, may help prevent vision loss.