Diabetes is associated with many ocular complications, but diabetic retinopathy is by far the most serious complication of all. In the United States, diabetic retinopathy is the leading cause of blindness among adults, ages 20 to 74 years old.
Thanks to a series of medical advances, ophthalmologists have a lot to offer to patients with diabetic retinopathy. However, the best outcome occurs when sight is still normal. The earlier diabetic retinopathy is detected, the more we are able to help our patients.
Diabetic retinopathy is caused by damage to the blood vessels in the retina, the light sensing film in the back of the eye. Through dilated pupils, a physician can directly visualize abnormal blood vessels, retinal swelling and retinal hemorrhages. In advanced cases, new blood vessels develop and, if left unattended, they will bleed and cause severe loss of vision. Diabetic retinopathy can be classified as either non-proliferative diabetic retinopathy or proliferative retinopathy.
How does diabetes affect the eye?
Diabetes can affect virtually every part of the eye, but involvement of the retina is the most worrisome complication of diabetic eye disease. In non-proliferative or background retinopathy, the center of the retina (macula) may become involved by swelling (edema) from retinal vessels that become altered by diabetes. This macular swelling can cause a visual loss that can usually be stopped by laser treatment. Because early macular swelling may not be perceived by the patient, routine eye examinations for all patients with diabetes are critically important for preservation of vision.
A second major area of involvement of the retina in diabetes is proliferative retinopathy, the formation of abnormal new blood vessels (neovascularization) that grow out of the retina into the formerly clear vitreous gel in the center of the eye. These vessels will usually bleed into the vitreous, causing impairment that can range from a few floaters to severe visual loss; these vessels may also exert traction on the retina resulting in a retinal detachment, which can also cause severe visual loss. In many patients with neovascularization, bleeding and retinal detachment occur together. Lasers are the usual treatment for neovascularization if the vessels are detected when the eye is clear enough and the retina has not detached. However, patients with severe bleeding or retinal detachment involving the central vision typically require surgery.
How does diabetic retinopathy cause vision loss?
Diabetic retinopathy causes loss of vision in several ways. Central vision may be impaired by fluid accumulation or poor circulation after years of gradual damage to the vessels in the macula, the most crucial part of the retina. Reading and driving depend on a well functioning macula. In more advanced cases of diabetic retinopathy, severe visual loss occurs from the formation and bleeding of new blood vessels.
Eye care specialists that make up our physician staff are certified by the American Board of Ophthalmology or are board-eligible and preparing for certification.