Description

Of the many attempts to classify diabetic retinopathy, the most widely used is a modified version of the Airlie-House Classification. This classifies retinopathy according to specific clinical features, so aiding interpretation and management. Background retinopathy may present with visible microaneurysms, dot and blot haemorrhages, flame haemorrhages, exudates, foveal avascular zone abnormalities and retinal oedema. Pre-proliferative retinopathy may characteristically show significant venous abnormalities, multiple cotton wool spots and intraretinal microvascular abnormalities. Proliferative retinopathy describes the appearance of fibrovascular proliferation. Further complications of proliferation (vitreous haemorrhage, tractional retinal detachment and rubeotic or haemolytic secondary glaucoma) are described as advanced diabetic retinopathy. At any point in the progression of the disease a leakage close to the fovea may threaten vision and is described as maculopathy. Subsequent extensive fibrosis may be termed as involutional proliferative retinopathy. The nature and appearance of each of these clinical features is discussed.