What is diabetic retinopathy?
Diabetic retinopathy is a potentially serious eye disease caused by diabetes. It affects the retina - the light-sensitive tissue at the back of the eye that transmits visual messages to the brain. Damage to this delicate tissue may result in visual impairment or blindness.
Diabetic retinopathy begins with a slight deterioration in the small blood vessels of the retina. Portions of the vessel walls balloon outward and fluid starts to leak from the vessels into the surrounding retinal tissue.
Subsequent developments (vascular proliferation, bleeding, retinal scarring, detachment, etc.) are all either directly or indirectly due to the retinal ischemia that results from vascular damage.
Generally, these initial changes in the retina cause no visual symptoms. However, they can be detected by an eye specialist who is trained to recognize subtle signs of retinal disease.
In many people with diabetic retinopathy, the disease remains mild and never causes visual problems. But in some individuals, continued leakage from the retinal blood vessels leads to MACULAR EDEMA.
This is a build-up of fluid in the macula - the part of the retina responsible for the sharp, clear vision used in reading and driving.
When critical areas of the macula become swollen with excess fluid, vision may be so badly blurred that these activities become difficult or impossible.
Some people with diabetes develop an even more sight-threatening condition called PROLIFERATIVE RETINOPATHY.
It may occur in people who have macular edema, but also can develop in those who don't. In proliferative retinopathy, abnormal new blood vessels grow on the surface of the retina.
These fragile new vessels can easily rupture and bleed into the middle of the eye, blocking vision. Scar tissue also may form near the retina, ultimately detaching it from the back of the eye.
Severe visual loss, even permanent blindness, may result. But this happens in only a small minority of people with diabetes.
- American Diabetes Association
1660 Duke St.
Alexandria, VA 22314
- Juvenile Diabetes Foundation
432 Park Ave. South, 16th floor,
New York, NY 10016
- Wisconsin Chronic Disease Prevention Program
1 West Wilson St.
P.O. Box 2659
Madison, WI 53701-2659