Diabetic retinopathy is an eye disease that only affects diabetics. It occurs when the fragile vascular network that supplies the retina – the light sensitive tissue at the back of the eye that helps us see – begins to swell or leak. During the beginning stages of the disease, there may be no noticeable symptoms, so it’s important to have your eyes checked at least once a year, if you have diabetes. Once symptoms of diabetic retinopathy do develop, they can include dark or black spots in your visual field, or blurry vision, and it increases over time.