The brain and eye, two of the most vital organs in the human body receive their blood supply via 4 major arteries (left and right carotid and vertebral arteries) that travel thought the neck. (Fig. 1)
Blockage of such vital arteries could prevent blood flow to the brain and eye which can lead to stroke, most commonly, or blindness.
The most common cause of carotid artery blockage is atherosclerosis. Other less frequent conditions that may block the carotid arteries include carotid aneurysm, autoimmune arteritides, and dissections. Such conditions may also pose a risk to the brain or eye.