Retinal vascular manifestations of metabolic disorders.

Metabolic diseases have profound effects on the structure and function of the retinal circulation. The recent development of retinal photography and digital imaging has enabled more precise documentation of diabetic retinopathy, as well as other retinal microvascular changes, such as retinal arteriolar narrowing, venular dilation and isolated retinopathy signs in nondiabetic individuals. These retinal microvascular signs have been shown to be associated with long-term risks of type 2 diabetes and hypertension, components of the metabolic syndrome (e.g. obesity, dyslipidemia), and a range of macro- and micro-vascular conditions (e.g. stroke, cardiovascular mortality). There is evidence that endothelial dysfunction and inflammation might be possible mechanisms involved in the development of various retinal microvascular changes in patients with diabetes, hypertension and other metabolic disorders. Further understanding of how these processes influence the retinal vasculature might help to elucidate the diverse vascular manifestations of metabolic diseases.