A stroke occurs when a blood vessel carrying oxygen and nutrients to the brain is blocked by a clot or bursts, causing the brain to starve. If deprived of oxygen for even a short period of time, the brain nerve cells will start to die. Once the brain cells die from a lack of oxygen, the part of the body that section of the brain controls is affected through paralysis, language, motor skills, or vision.
Strokes caused by blood clots that block the artery are ischemic (is-KEM-ik) strokes. This is the most common type, accounting for 70-80 percent of all strokes.
When a blood vessel ruptures, it causes a bleeding or hemorrhagic (hem-o-RAJ-ik) stroke. Once the brain cells die from a lack of oxygen, the part of the body controlled by that section of the brain is affected. Strokes can cause paralysis or language, motor skills or vision difficulties.
There Are Also "Mini-Strokes"
There are also "mini-strokes" known as TIA's (transient ischemic attacks). People who have one TIA are likely to have another one. TIAs cause brief stroke symptoms that go away after a few minutes or hours. People often ignore these symptoms, but they are an early warning sign and 35 percent of those who experience a TIA will have a full blown stroke if left untreated. TIAs should be taken as seriously as stroke.
The most common symptoms of stroke are:
If you experience any of these symptoms, even if they go away quickly, seek immediate emergency help.
Every minute counts. Although starved of oxygen, brain tissue does not die in the minutes following a stroke. If blocked blood vessels can be opened within three to six hours, the chances of recovery are greatly improved.
Prevention and Carotid Stenting
As vascular experts, interventional radiologists and vascular surgeons treat atherosclerosis, "hardening of the arteries," throughout the body. In some patients, atherosclerosis, specifically in the carotid artery in the neck, can lead to ischemic stroke. Plaque in the carotid artery may result in a stroke by either decreasing blood flow to the brain or by breaking loose and floating into a smaller vessel, depriving a portion of the brain of blood flow. In patients at high risk of having a stroke, the narrowed section of artery may be reopened by a vascular specialist through angioplasty and reinforced with a stent, thereby preventing the stroke from occurring. Vascular stents are typically made of woven, laser-cut or welded metal that permits the device to be compressed onto a catheter and delivered directly into the hardened artery. In addition to diagnosing and treating those at risk for stroke, vascular specialists use their expertise in imaging, angioplasty and stenting to treat those having an acute stroke. Patients can also take action to prevent strokes by:
Physical examination. Your doctor may be able to assess your risk for stroke during a routine physical examination. If your physician suspects that you may be at high risk, he or she will ask if you have experienced symptoms such as numbness or muscle weakness, speech or vision difficulties, or lightheadedness. By listening to the carotid artery through a stethoscope, the doctor may hear a rushing sound, called a bruit ("brew-ee") that suggests the artery may be obstructed. Physical exam is not always accurate, however, and further tests may be ordered.
Stroke Facts and Statistics
“Reprinted with permission of the Society of Interventional Radiology 2004, 2011, www.SIRweb.org. All rights reserved.”