Ischemia comes from the Greek meaning “reduced blood” to any organ. Ischemic strokes occur because a blood clot blocks an artery or vessel in the brain. The most common cause is atherosclerosis, a process in which fatty deposits (plaque) form in the vessel walls of the brain. A stroke sometimes occurs because plaque develops in the carotid artery, the main blood vessel in the neck that supplies oxygen to the brain.
Figure 1. Narrowed vessel Figure 2. a vessel with fatty deposits (plaques) form in the vessel walls.
The symptoms of brain ischemia may be transient, lasting seconds to minutes, or can persist for longer periods of time. Blockage of a blood vessel can cause ischemia, and the brain tissues supplied with oxygen by that vessel may die. This tissue death is called an infarct. Unfortunately, neurologic symptoms do not always accurately reflect the presence or absence of infarction.
Besides lowering stroke risk through lifestyle changes and medication, which can help to reduce blood pressure and cholesterol, surgery to remove plaque and other tissue damage may be beneficial.