Eye Disorders: Diabetic Retinopathy
Diabetes causes changes to the small blood vessels all over the body, including the retina. The retina is a layer of nerve cells in the back of the eye that "takes a picture" of what the eye is looking at. There are two stages of diabetic retinopathy. The first stage, called "non-proliferative," means the small blood vessels are leaking blood and fluid into the retina. Sometimes the leaking causes blurring due to "macular edema," which is swelling in the part of the retina responsible for sharp vision. The second and later stage, called "proliferative," means that new blood vessels (neovascularization) are starting to grow in the retina. Unfortunately these new blood vessels can cause a retinal detachment, glaucoma (high pressure), or bleed profusely (vitreous hemorrhage), causing severe loss of vision.
What are the symptoms of diabetic retinopathy?
Vision loss, the primary concern with diabetic retinopathy, can occur for many reasons. In fact, diabetic retinopathy is a leading cause of permanent vision loss in this country. Macular edema (swelling), closure of the small blood vessels feeding the retina (retinal and macular ischemia), retinal detachment from neovascularization, and vitreous hemorrhage from neovascularization, are common causes of vision loss.
How is diabetic retinopathy treated?
The first line of defense against diabetic retinopathy is good blood sugar control. Studies conclusively show that people who keep their blood sugar (hemoglobin A1C) close to a normal range have less retinopathy and better vision than those who don't. Yearly eye examinations are recommended to monitor for the onset of diabetic retinopathy. Once retinopathy is identified, its progress needs to be monitored. If the retinopathy meets one of several treatment criteria, laser surgery will be performed with the goal of stabilizing the situation and preserving vision. The most common situations where laser treatment may be recommended is macular edema and neovascularization. In severe situations, a vitrectomy (removal of the jelly inside the eye) may be performed. Fortunately, with good monitoring and treatment, most people with diabetic retinopathy can expect to retain useful vision during their lives.
More information on diabetic retinopathy can be found at the National Eye Institute's website