Diabetic retinopathy is a complication of diabetes that results from damage to the blood vessels of the light-sensitive tissue at the back of the eye (retina).Initially diabetic retinopathy may cause no symptoms or only mild fluctuating vision. Eventually, however, diabetic retinopathy can result in blindness.

Diabetic retinopathy can develop in anyone who has type 1 diabetes or type 2 diabetes. The longer you have diabetes, and the less controlled your blood sugar is, the more likely you are to develop diabetic retinopathy.

To protect your vision, take prevention seriously. Start by carefully controlling your blood sugar level and scheduling yearly eye exams.

Symptoms
It's possible to have diabetic retinopathy and not know it. In fact, it's uncommon to have symptoms in the early stages of diabetic retinopathy.
As the condition progresses, diabetic retinopathy symptoms may include:

Diabetic retinopathy usually affects both eyes.

Normal vs. Diabetic Retinopathy

When to see a doctor
Careful management of your diabetes is the best way to prevent vision loss. If you have diabetes, see your eye doctor for a yearly dilated eye exam — even if your vision seems fine — because it's important to detect diabetic retinopathy in the early stages. If you become pregnant, your eye doctor may recommend additional eye exams throughout your pregnancy, because pregnancy can sometimes worsen diabetic retinopathy.
Contact your eye doctor right away if you experience sudden vision changes or your vision becomes blurry.

In the early stages of diabetic retinopathy, the walls of the blood vessels in your retina weaken. Tiny bulges protrude from the vessel walls, sometimes leaking or oozing fluid and blood into the retina. Nerve fibers in the retina may swell, producing white spots in the retina. As diabetic retinopathy progresses, new blood vessels may grow and threaten your vision.
Diabetes is associated with the tiny blood vessels (capillaries) that nourish the retina. This can result in diabetic retinopathy and vision loss. Elevated blood sugar levels can also affect the eyes' lenses. With high levels of sugar over long periods of time, the lenses can swell, providing another cause of blurred vision.