Correlation between Retinal Nerve Fibre Layer Thickness and Glycosylated Haemoglobin in Non Proliferative Diabetic Retinopathy

Abstract

iabetes mellitus is a metabolic disorder characterized by chronic hyperglyaemia. Diabetes cause many complication. diabetic retinopathy is common complication which affects up to 80 percent of all patients who have diabetes for more than10 years or more. Retinal functional abnormalities as reduced contrast sensitivity and ERG abnormalities could be detected in diabetic patients before microvascular lesions can be detected in ophalmological examination. It is thought that chronic hyperglycemia causes cellular affection; in the form of increased intracellular glycation end products, oxidative stress and activation protein c kinase isoforms. Theses stresses eventually lead to apoptosis and proinflammatory events. Several studies showed specific cellular defects in the neurosensory retina. These studies included evidence of müllar cell activation, abnormal glutamate metabolism and microglial cell activation It is becoming clear that neuronal cells of retina are affected by diabetes, resulting in dysfunction and degeneneration of some neuronal cells. Retinal nerve fiber layer is an important structural neuron in the retina which is often shown to be affected in the early pathogenesis of diabetic retinopathy. In recent years, several studies have indicated