Hypertension and the eye

The retina provides an opportunity for in vivo visualization of the microvasculature. In systemic hypertension, the retina shows characteristic progressive changes which have been termed hypertensive retinopathy. The extent of these changes correlates with increased risk of systemic cardiovascular disorders. In addition, hypertension itself is a risk factor for several ocular disorders including retinal artery and vein occlusion, anterior ischemic optic neuropathy, and microvascular oculomotor nerve palsies. Glaucoma has been associated with both hypertension and hypotension, with the implication that over-treatment of blood pressure may be detrimental to glaucomatous optic neuropathy. The retinal arteries and veins can be imaged and their diameters estimated to provide an index that may be used as a marker for systemic vascular change. Dynamic changes in vessel diameter can be recorded with video-imaging with the aim of assessing arterial stiffness, while optical coherence tomography angiography (OCT-A) provides a new non-invasive technique to assess the microvascular density. Here, we review links between retinopathy and both systemic and ocular disease, and some of the techniques for assessing retinal vessels.