Diabetic Retinopathy, Vision & Vision Loss

Diabetic retinopathy begins with mild deterioration of the tiny blood vessels that nourish the retina. Portions of the vessels may develop bulges (microaneurysms) that leak blood (hemorrhages), fluid (edema), or lipids (exudates) into the surrounding tissue. Generally, vision remains stable during these early, or nonproliferative, changes unless swelling in the macula (the central, most sensitive portion of the retina) develops.

Later, some individuals may develop the more serious stage of diabetic retinopathy, called proliferative retinopathy, in which abnormal blood vessels grow from the retina and into or onto the back surface of the vitreous humor. These fragile vessels are prone to rupture and can bleed into the vitreous, causing blurred vision or temporary blindness.

Scar tissue may form, pulling the retina away from the back of the eye—a condition known as retinal detachment, which may require treatment to minimize vision loss.

The type of visual impairment caused by diabetic retinopathy is highly variable, depending on the location of retinal damage. Possible effects include blurring, distortion, and blind spots. In either stage of the disease, a vision-threatening complication called macular edema—in which fluid accumulates in the macula—may develop.

Because even advanced retinopathy may not cause symptoms, it is essential for people with diabetes to have regular check ups by an ophthalmologist and to report any vision changes immediately. If detected early enough, the most frequent causes of vision loss—new blood vessel growth, retinal detachment, and macular edema—can be, in many cases, minimized with medications injected into the eye, laser treatment, or surgery.

Publication Review By: Susan B. Bressler, M.D., Harry A. Quigley, M.D., Oliver D. Schein, M.D., M.P.H.

Published: 28 Feb 2011

Last Modified: 07 Sep 2011