Diabetic retinopathy is one of several forms of diabetic eye disease. According to the National Eye Institute, diabetic retinopathy is the most common eye disease affecting people with diabetes and is a leading cause of new blindness in American adults.

What Is Diabetic Retinopathy?

The retina is the light-sensitive tissue inside the back of each eye. The retina turns light into signals that travel down the optic nerve directly to the brain, where they are translated into visual images. Damage to this visual pathway can cause various types of vision loss.

Causes of Diabetic Retinopathy

Diabetic retinopathy is a serious complication of diabetes. Over time, elevated levels of blood sugar damage blood vessels all over the body, including the tiny, delicate blood vessels in the retina. This condition leads to vision problems and potentially, blindness.

Types of Diabetic Retinopathy

According to the National Eye Institute, there are four stages of diabetic retinopathy:

• mild non-proliferative diabetic retinopathy (NPDR), in which tiny retinal blood vessels begin to weaken and swell. At this stage these blood vessels do not often cause vision problems and can only be seen during an eye examination
• moderate NPDR, in which blood vessels start to become blocked, diminishing blood flow to the retina
• severe NPDR, in which more blood vessels become blocked, cutting off retinal blood supply
• proliferative diabetic retinopathy (PDR), the advanced form of DR in which blood vessel blockage triggers new vessels to form (neovascularization)

In advanced DR, the new blood vessels that form are abnormally fragile and can bleed into the space in front of the retina. This bleeding can cause visual symptoms, serious complications such as retinal detachment, and potentially, vision loss.

Signs and Symptoms of Diabetic Retinopathy

Diabetic retinopathy usually does not cause symptoms in the early stages. Symptoms in the advanced stage may include:

• blurry vision due to macular edema, a swelling in the retina
• colors that look faded or washed out
• floating dark spots or shapes in the field of vision due to bleeding inside in the eye
• frequent changes in vision, from blurry to clear and back again
• poor night vision
• vision loss

How Is Diabetic Retinopathy Diagnosed?

To diagnose diabetic retinopathy, an eye care professional will check for signs of leaking blood vessels, swelling, damaged nerve tissue and other problems inside the eyes. Tests may include:

• dilated eye exam, in which drops are placed in the eyes to widen the pupils, making it easier to closely examine the retina and optic nerve
• tonometry test, which measures pressure inside the eye
• visual acuity test to measure sharpness of vision at various distances

Treatments for Diabetic Retinopathy

With early diagnosis and prompt treatment, it is possible to slow down or reverse diabetic retinopathy. Options may include:

• corticosteroids, medications that reduce swelling and improve vision
• injections of anti-VEGF (vascular endothelial growth factor) drugs, medications that slow or stop the growth of abnormal blood vessels in the retina
• scatter laser surgery, also called panretinal photocoagulation, which uses a special laser to shrink blood vessels inside the eye
• vitrectomy surgery, a procedure to repair a detached retina and/or replace cloudy vitreous fluid inside the eye with a clear solution

Click here to assess your risk for diabetes.