Diabetic retinopathy is a complication of diabetes mellitus and is the leading reason for vision loss in diabetic patients. In diabetic patients, high sugar (glucose) levels damages blood vessels in every organ in the body, including the retina, and results in leakage of fluid and blood from the vessel into the retina. Accumulation of this leakage and blood causes swelling (macular edema) and can prompt the growth of new, fragile blood vessels (neovascularization). Both macular edema and neovascularization of the retina can cause loss of central and possibly peripheral vision.
Risk factors for diabetic retinopathy include increased duration of diabetes, poor diabetic control (high sugar levels) and large fluctuations in sugar levels. After 25 years of having diabetes, nearly all patients will have some evidence of diabetic retinopathy. To decrease the development of diabetic retinopathy and to slow the progression from mild to more significant disease, ophthalmologists recommend that patients keep their Hemoglobin A1c (a blood level that reflects how well blood sugars are controlled over a three month period) under 7.0.
There are several treatment methods to help patients maintain and/or gain vision due to diabetic macular edema or retinal neovascularization, These options include intravitreal injections (injections of a medication into the jell-like substance in the back of the eye) of a vascular endothelial growth factor (VEGF) inhibitor (Avastin, Lucentis and Eyela) or steroids (Ozurdex and Triamcinolone), of the use of lasers.
All patients with diabetes should have at least an annual dilated retinal examination even in the absence of visual symptoms to ensure there are no early warning signs of diabetic retinopathy.