Proliferative diabetic retinopathy (PDR) is an eye condition that affects millions of Americans. The advanced form of diabetic retinopathy, PDR can lead to serious eye problems, including blindness. (Learn More)

Diabetic retinopathy is caused by prolonged periods of elevated blood sugar levels. High blood sugar levels cause damage throughout the body, including to the eye. (Learn More) Diabetic retinopathy is a progressive disease that will continue to get worse if left untreated. (Learn More)

Anyone with diabetes is at risk of developing PDR. People with type 1, type 2, or gestational diabetes must be aware of the signs of PDR. (Learn More)

Proliferative and non-proliferative diabetic retinopathy (NPDR) are the two types of diabetic retinopathy. NPDR marks the beginning stages of diabetic retinopathy, while PDR is more advanced. (Learn More)

man covering eye in pain

Conscious lifestyle choices and ongoing consultation with your eye doctor can prevent the progression of PDR. (Learn More)

Treatment options for PDR depend on the stage of the disease in your eye. Medical control (managing your diet and using medications) may be enough to prevent PDR from developing. Advanced stages of PDR may require laser treatments or eye surgery. (Learn More)

The National Eye Institute estimates that the number of cases of diabetic retinopathy in the U.S. will double from 7.7 million in 2010 to over 14 million by 2050. Fortunately, there are many treatment options and lifestyle interventions available to manage diabetic retinopathy. (Learn More)

What Is Proliferative Diabetic Retinopathy?

Diabetic retinopathy is an eye condition that can occur in people who have diabetes. It causes damage to the retina, typically in both eyes, and it gets progressively worse over time. It is a serious condition that can lead to total vision loss.

Proliferative diabetic retinopathy (PDR) is the advanced form of diabetic retinopathy. With PDR, circulation problems in the eye prevent enough oxygen from reaching the retina. In response to the lack of oxygen, small blood vessels grow into the retina and the vitreous (the clear gel-like substance in the eye). Vision becomes cloudy when the blood vessels break or leak blood into the vitreous.

Symptoms of diabetic retinopathy include:

  • Seeing floaters or dark spots in vision.
  • Indistinct vision.
  • Seeing a dark or blank spot in the middle of your vision.
  • Trouble seeing clearly at night.

Causes of Diabetic Retinopathy

Diabetic retinopathy is caused by too much sugar in the blood, which damages the body, including the eye. The American Optometric Association (AOA) explains that over time, diabetes harms small blood vessels in the retina. As these blood vessels are damaged, blood and other fluids leak into the retina.

As additional fluids leak into the retina, the retinal tissue swells, which leads to cloudy or blurred vision. Diabetic retinopathy can also cause damage to the eye when people with diabetes have elevated blood sugar levels for extended periods of time. High blood sugar can cause fluid to build up in the lens in the eye, which is responsible for focus.

The fluid buildup affects the curvature of your lens and thus your eye’s focusing power. Once blood sugar levels return to normal, however, the lens typically also resumes its original shape, and you can see clearly once again.

Who Is at Risk for PDR?

There are a few groups of people who are at risk of developing PDR. According to the National Eye Institute (NEI), anyone with any kind of diabetes can develop diabetic retinopathy. This includes:

  • People with type 1 diabetes.
  • People with type 2 diabetes.
  • Women who develop gestational diabetes during pregnancy.

If you develop gestational diabetes while pregnant, you are at an increased risk of developing diabetic retinopathy. Your doctor may refer you for a comprehensive eye exam while pregnant to monitor the situation. The condition can develop while you are pregnant, as well as after your pregnancy is over and you no longer have gestational diabetes.

Timeline of Progression

The longer a person has diabetes, the greater their chances of developing diabetic retinopathy.

The primary symptom of diabetic retinopathy is progressive loss of vision. How quickly the condition progresses is based on your personal history of diabetes, as well as how well your blood sugar and other health factors are being maintained.

The progression of diabetic retinopathy usually follows this timeline:

  • Someone has diabetes for many years.
  • Blood sugar levels are not well controlled.
  • Retinal damage occurs.
  • New abnormal blood vessels begin to grow.
  • New blood vessels leak and cloud the vitreous.
  • Retinal scarring occurs.
  • The macula becomes distorted.
  • Vitreous hemorrhage and retinal detachment can occur.
  • Partial or total vision loss happens.

The Columbia University Department of Ophthalmology explains that people who have had diabetes for over 30 years are 65 percent more likely to develop retinopathy than people without diabetes.

It is important to seek ongoing treatment for diabetic retinopathy. If left untreated, the condition can cause blindness.

Proliferative vs. Non-Proliferative Diabetic Retinopathy

There are two types of diabetic retinopathy: non-proliferative and proliferative.

Both types of diabetic retinopathy are due to damage to the retina caused by diabetes. They vary in the following ways:

  • Non-proliferative diabetic retinopathy (NPDR): This is the beginning stage of diabetic retinopathy where symptoms are mild or not noticeable yet.Blood vessels in the retina have become weakened at this point, but new ones have not yet begun to form. Existing blood vessels may have developed small bulges (microaneurysms) that leak fluid into the retina. Some swelling of the macula may occur, causing your vision to be blurry.
  • Proliferative diabetic retinopathy (PDR): This is the more advanced form of the disease where vision is being impaired. The retina is struggling to get enough oxygen due to poor circulation and too much swelling. Fragile, abnormal blood vessels grow in the retina out into the vitreous. These blood vessels, along with any leakage of blood, cloud vision.

In addition to the above differences associated with the two stages of diabetic retinopathy, PDR poses further complications. Other risks associated with PDR include:

  • Formation of scar tissue on the retina.
  • Retinal detachment.
  • Greatly increased eye pressure.
  • Damage to the optic nerve.
  • Glaucoma.
  • Vision loss and blindness.

Can PDR Be Prevented?

AOA explains that people with diabetes who are able to control their blood sugar levels well are able to slow the onset and progression of PDR.

Other ways to prevent the development of diabetic retinopathy include:

  • Take your medications as prescribed.
  • Adhere to a healthy diet.
  • Exercise regularly.
  • Maintain good blood pressure and cholesterol.
  • Don’t smoke.

In addition to the above prevention methods, it is important to regularly receive dilated eye exams. Through these exams, your eye doctor can recognize early signs of diabetic retinopathy before you exhibit any symptoms. Early recognition and treatment of the condition are imperative for preventing vision loss.

Treatment Options

The treatment options for diabetic retinopathy depend on how advanced the condition is and what your eye doctor sees through a comprehensive vision exam, explains the American Academy of Ophthalmology (AAO).

Treatment options for PDR include:

  • Medical control. Your blood sugar and blood pressure will be closely controlled to prevent eye damage and vision loss.
  • Laser treatment. Lasers can be used to seal leaking blood vessels.
  • Medications. These can be injected into the eye to reduce inflammation and prevent new blood vessels from forming.
  • Vitrectomy. This is a surgical procedure that removes the vitreous in your eye that has become too cloudy and replaces it with new, clear artificial fluid.
  • Surgery. This can be used to repair a retinal detachment caused by PDR.

The cost of treatment varies greatly depending on what level of intervention you require. Lifestyle changes to manage your diabetes better often cost nothing, while prescription medications and surgical options will cost significantly more.

Most insurance plans cover the cost of medically necessary interventions. Consult your individual medical insurance provider to find out which treatment options are covered by your insurance and what will come at an out-of-pocket expense to you.

Surgeons performing an eye surgery under the microscope at the hospital - healthcare and medicine concepts

The Outlook for PDR

According to NEI, diabetic retinopathy is the most common eye disease seen among people with diabetes, and it is a leading cause of blindness in all adult Americans. From 2000 to 2010, the number of people diagnosed with diabetic retinopathy increased by 89 percent. As of 2010, over 7.6 million people in the U.S. had diabetic retinopathy.

NEI predicts that from 2010 to 2050, the number of people in the U.S. with diabetic retinopathy will almost double from 7.7 million to over 14.5 million people. To slow the number of diagnoses of PDR, it is important that people with diabetes stay on top of their health, particularly their blood sugar levels.

PDR is a progressive disease, but through early detection and ongoing treatment, the progression of the condition can be slowed down greatly. Regular eye exams are essential for preventing diabetic retinopathy from advancing to PDR.



Diabetic Retinopathy. American Optometric Association.

Diabetic Retinopathy. (August 2019). National Eye Institute.

Diabetic Retinopathy Data and Statistics. (July 2019). National Eye Institute.

Proliferative Diabetic Retinopathy (PDR). Columbia University Department of Ophthalmology.

What Is Diabetic Retinopathy? (October 2019). American Academy of Ophthalmology.