Retinal changes due to diabetic retinopathy may initially be symptomless. Diabetic retinopathy can be divided into two stages based on examination of retina.
The stages are-
- Non-proliferative diabetic retinopathy – Small balloon-like swellings called microaneurysms develop in the blood vessels of the retina. As the disease progresses, some of the blood vessels get blocked. Hence, several areas of the retina are deprived of blood supply and are damaged. These damaged areas signal the body to grow new blood vessels for nourishment.
- Proliferative diabetic retinopathy (PDR) – Growth of new blood vessels is triggered. However, the new blood vessels are abnormal and fragile; and severe vision loss can occur if these vessels leak blood.