Evaluation of Type2 Diabetes Mellitus Effect on Human Cornea using Specular Microscopy and Pentacam Corneal Tomography

Abstract

iabetes Mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. The chronic hyperglycemia of diabetes is associated with long-term damage, dysfunction, and failure of different organs, especially the eyes, kidneys, nerves, heart, and blood vessels Advanced glycated end products (AGEs) are sugar-derived irreversible protein modifications that have been implicated in the pathogenesis of diabetic complications, such as retinopathy, keratopathy, nephropathy and neuropathy. In the cornea, for example, the Millard reaction probably plays a significant role in altering structural proteins during diabetes and aging. Diabetic keratopathy has an association with neuropathic disease and is manifested by thickening of the corneal stroma and Descemet's/Bowman's basal laminae, recurrent erosions, corneal edema and morphological abnormalities in the epithelial and endothelial layers. Corneal evaluation was performed using topography systems with “Placido-based” technology, which was considered inaccurate by some authors as it lacks the assessment of the posterior corneal surface and corneal pachymetry. These important data were later detected using “Elevation-based” corneal imaging techniques, with Pentacam being one of the most popular devices.