There is a close link between vascular (blood vessels) health and eye health. Long-term eye health is dependent on the consistent supply of blood, and the oxygen within it, to the eye via thousands of blood vessels.
Amaurosis fugax describes a loss of vision in one eye caused by a temporary shortage of oxygen delivered to the optic nerve. The interruption of oxygen and blood flow is caused by a clot or plaque that blocks an artery but is quickly dislodged, causing partial vision loss for several minutes. While the vision loss is usually temporary, this is an often-overlooked warning sign of an impending stroke.
A related but more serious event occurs when the plaque obstructs a blood vessel in the eye for more than 90 minutes, producing a sudden and permanent loss of vision, typically in just one eye. These problems are described as a central or branch retinal artery occlusion.
While classified as both a vascular and immunologic disease, giant cell (or temporal) arteritis also can restrict blood flow to the eye and specifically to the posterior ciliary arteries, causing vision loss. This condition typically affects patients over sixty years old, and can be effectively managed with medication if identified in a timely manner. High blood pressure impairs blood circulation throughout the entire body, and can cause hemorrhages in the tiny blood vessels supplying the eye. The hemorrhages can eventually damage the retina and obstruct vision.