Diabetic Retinopathy is damage to the retina caused by complications of diabetes mellitus, and can often lead to blindness. It often has no early warning signs, so early detection is very important.
Small blood vessels – such as those in the eye – are especially vulnerable to poor blood sugar (blood glucose) control. An over-accumulation of glucose and/or fructose damages the tiny blood vessels in the retina. During the initial stage, called non-proliferative diabetic retinopathy (NPDR), most people do not notice any change in their vision.
Some people develop a condition called macular edema. It occurs when the damaged blood vessels leak fluid and lipids onto the macula, the part of the retina that lets us see detail. The fluid makes the macula swell, which blurs vision.
As the disease progresses, the lack of oxygen in the retina causes fragile new blood vessels to grow along the retina and in the clear, gel-like vitreous humour that fills the inside of the eye. Without timely treatment, these new blood vessels can bleed, cloud vision, and destroy the retina.