Types of Diabetic Retinopathy
There are two types of diabetic retinopathy: nonproliferative diabetic retinopathy (NPDR) and proliferate diabetic retinopathy (PDR).
NPDR, commonly known as background retinopathy, is an early stage of diabetic reinopahty. 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.
Many people with diabetes have mild NPDR, which usually does not affect their vision. When vision is affected it is the result of macular edema and/or macular ischemia.
PDR is present when abnormal new vessels (neovascularization) begin growing on the surface of the retina or optic nerve. The main cause of PDR is widespread closure of retinal blood vessels, preventing adequate blood flow. The retina responds by growing new blood vessels in an attempt to supply blood to the area where the original vessels closed.
Unfortunately, the new, abnormal blood vessels do not re-supply the retina with normal blood flow. The new vessels are often accompanied by scare tissue that may cause wrinkling or detachment of the retina