Optical coherence tomography for complete management of patients with diabetic retinopathy.

Diabetic retinopathy is a major complication of patients with diabetes mellitus and can lead to a decrease in vision. The precise mechanisms leading to the development of diabetic retinopathy and the progressive decrease of vision are still undetermined. Recent studies have shown that not only vascular but also neuronal abnormalities are associated with the pathogenesis of diabetic retinopathy. Because neuronal cell death leads to an irreversible decrease in visual function, early changes in the morphology and physiology of the neural retinas of diabetic patients are important. The alterations of the morphology of the retina can be obtained by high-resolution B-scan optical coherence tomography (OCT). The thickness of the macular area and retinal nerve fiber layer can be measured reliably and accurately by the installed software of OCT instruments. The high-resolution images can be used to evaluate diabetic macular edema and optic nerve damage quantitatively in patients with diabetic retinopathy. This review describes how the OCT measurements can be used to manage patients with diabetic retinopathy. We also present the early retinal changes involved in the pathogenesis of diabetic retinopathy.