Sometimes, tiny bulges (microaneurysms) protrude from the vessel walls, leaking or oozing fluid and blood into the retina. This fluid can cause swelling (edema) in the central part of the retina (macula). This is a serious eye complication called diabetic macular edema that can cause vision problems or blindness. Macular edema is reversible in the early stages but chronic edema may lead to irreversible changes in the retina. Prevention. Sometimes, there is nothing you can do to prevent diabetic retinopathy or DME, but your best chance at avoiding them comes by maintaining a healthy lifestyle, exercising regularly, eating lots of vegetables and fruit, and visiting your eye doctor at least once a year to stay on top of your eye health.