If you have diabetes mellitus, you should know that high blood sugar levels can damage blood vessels in the retina – the nerve layer at the back of the eye that senses light and helps to send images to the brain. The damage to retinal vessels is referred to as diabetic retinopathy.
There are two types of diabetic retinopathy: nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR).
NPDR, also known as background retinopathy, is an early stage of diabetic retinopathy. In this stage, tiny blood vessels within the retina leak blood or fluid. The leaking fluid causes the retina to swell or to form deposits called exudates.
PDR is present when abnormal new vessels ... Read more