Other retinal conditions in diabetes

Systemic hypertension is all too frequently co‐existent with diabetes mellitus, meaning that it is often difficult or impossible to clearly differentiate which is the cause of a particular retinal lesion. Hypertensive retinopathy shares several common lesions with diabetic retinopathy, principally retinal haemorrhage, cotton wool spots, hard exudates and apparent vascular occlusions. Microaneurysms, intraretinal microvascular abnormalities (IRMA) and venous beading are not, however, features commonly associated with hypertension. In older patients, central retinal vein occlusion (CRVO) is commonly associated with diabetes, hypertension and arteriosclerosis. CRVO is a severe or total outflow obstruction to the main vein leaving the eye. This occurs out of sight of the observer and happens within the confines of the retrobulbar region of the optic disc. Occlusion of the central artery requires the blockage to have occurred in the retrobulbar region of the eye, before bifurcation of the central artery as it enters the visible globe