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Diabetic Retinopathy


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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The retina is a layer of cells at the back of your eye that's sensitive to light and sends signals to the brain that allow you to see.

The retina is fed by many small blood vessels. These blood vessels can become damaged in people with diabetes. The vessels can leak blood and damage the retina. Sometimes the damaged vessels grow back abnormally, which can make the problem worse.

What is diabetic retinopathy?

Diabetic retinopathy is damage to your retina caused by having diabetes. People with diabetes have high blood sugar. High blood sugar damages blood vessels. Small blood vessels in the kidney and the eye are especially at risk for damage.

  • Everyone with diabetes has some changes to their retina

  • You can have diabetic retinopathy and not know it

  • If diabetic retinopathy gets worse, you can have problems with your vision

  • Doctors treat severe diabetic retinopathy with laser treatments and shots into the eye

What causes diabetic retinopathy?

Diabetes can damage the blood vessels in the eyes. People with diabetes often also have high blood pressure. High blood pressure can also cause changes to the blood vessels in your eyes that can hurt your retinas.

Without treatment, diabetic retinopathy gets worse the longer you have diabetes. Pregnancy can also make diabetic retinopathy worse.

What are the symptoms of diabetic retinopathy?

You may not have symptoms at first, but usually diabetic retinopathy causes:

  • Slow, steady vision loss

  • Blind spots

  • Blurriness in the middle of your vision

Later, you may have symptoms such as:

  • Floaters (dark spots that seem to be moving across your field of vision)

  • Flashing lights

  • Sudden, severe, painless vision loss

Depending upon the areas of the retina that have been damaged, some people don't have vision loss even when diabetic retinopathy is severe.

How can doctors tell if I have diabetic retinopathy?

To tell if you have diabetic retinopathy, doctors will:

  • Use an ophthalmoscope (an instrument with a light for looking inside the eye) to look for leaky blood vessels and growth of abnormal new vessels

  • Give you a shot in your vein of a special dye that helps doctors see the blood vessels in your eye (a procedure called fluorescein angiography)

  • Take pictures of your retina

How do doctors treat diabetic retinopathy?

Controlling your blood sugar and blood pressure levels is important. Doctors will give you medicine and tell you how a good diet can help control your blood sugar and blood pressure. It's also important that you:

  • Get your blood sugar and blood pressure checked often

  • Have your eyes checked regularly by an eye doctor

  • Don't smoke, or stop if you do

Your doctor may also give you:

  • Laser surgery to stop blood vessels from leaking

  • Shots in your eye to slow growth of abnormal new blood vessels

  • Other surgical procedures if the retinopathy causes a lot of bleeding or a detached retina

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