Proliferative retinopathy consists of the following lesions except: A.Capillary microaneurysms B.Neovascularisation of the retina at optic disc C.Vitreous haemorrhages D.Proliferation of astrocytes and fibrous tissue around blood vessels
The development of retinopathy can be broken down into proliferative and non-proliferative types. Both types cause disease by altering the normal blood flow to the retina through different mechanisms. The retina is supplied by small vessel branches from the central retinal artery. Proliferative retinopathy refers to damaged caused by abnormal blood vessel growth.
Proliferative retinopathy is the result of aberrant blood flow to the retina due to blood vessel overgrowth, or neovascularization. These pathologically overgrown blood vessels are often fragile, weak, and ineffective at perfusing the retinal tissues. These weak, fragile vessels are also often leaky, allowing fluids, protein, and other debris to leech out into the retina. They are also prone to hemorrhage due to their poor strength.
In the non proliferative retinopathy, hyperglycemia results in damage to retinal capillaries. This weakens the capillary walls and results in small outpouchings of the vessel lumens, known as microaneurysms. Microaneurysms eventually rupture to form hemorrhages deep within the retina, confined by the internal limiting membrane (ILM). Because of their dot-like appearance, they are called "dot-and-blot" hemorrhages.
