Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. Diabetic retinopathy is damage to the blood vessels of the retina that occurs with long-term diabetes.
People with type 1 and type 2 diabetes are at risk for this condition. Many people with early diabetic retinopathy have no symptoms before major bleeding occurs in the eye. This is why everyone with diabetes should have regular eye exams.
To prevent progression of diabetic retinopathy, people with diabetes should control their levels of blood sugar, blood pressure, and blood cholesterol.
Symptoms of Diabetic Retinopathy
- Blurred vision and slow vision loss over time
- Shadows or missing areas of vision
- Trouble seeing at night
Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the most advanced stage of the disease. People with proliferative retinopathy can reduce their risk of blindness by 95 percent with timely treatment and appropriate follow-up care.
Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema. It is more likely to occur as the disease progresses.
Diabetic retinopathy and macular edema are detected during a comprehensive eye exam that includes:
- Visual acuity test. This eye chart test measures how well you see at various distances.
- Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. This allows the eye care professional to see more of the inside of your eyes to check for signs of the disease. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
- Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Your eye care professional checks your retina for early signs of the disease, including:
- Leaking blood vessels
- Retinal swelling (macular edema)
- Pale, fatty deposits on the retina–signs of leaking blood vessels
- Damaged nerve tissue
- Any changes to the blood vessels
If your eye care professional believes you need treatment for macular edema, he or she may suggest a fluorescein angiogram. In this test, a special dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your retina. The test allows your eye care professional to identify any leaking blood vessels and recommend treatment.
Treatment usually does not reverse damage that has already occurred. However, it can help keep the disease from getting worse. Once your eye doctor notices new blood vessels growing in your retina (neovascularization) or you develop macular edema, treatment is usually needed.
Several procedures or surgeries are the main treatment for diabetic retinopathy.
Laser eye surgery creates small burns in the retina where there are abnormal blood vessels. This process is called photocoagulation. It is used to keep vessels from leaking or to get rid of abnormal, fragile vessels.
- Focal laser photocoagulation is used to treat macular edema.
- Scatter laser treatment or panretinal photocoagulation treats a large area of your retina. Often two or more sessions are needed.
- A surgical procedure called vitrectomy is used when there is bleeding (hemorrhage) into the eye. It may also be used to repair retinal detachment.
Drugs that prevent abnormal blood vessels from growing, and corticosteroids injected into the eyeball are new treatments for diabetic retinopathy.
Other problems that may develop include: