Examination of the optic fundi may provide direct information on a variety of conditions that affect the cardiovascular system. In patients with hypertension the retinal changes are classified according to the Keith–Wagner–Barker method. These changes reflect both atherosclerotic and hypertensive retinopathy. Initially, arterial narrowing is seen (grade 1), and subsequently the arteriolar diameters increase in relation to the venous diameters, manifested as arteriovenous nicking (grade 2 changes)
