| HOME |
Symptoms and Causes of Stroke
A stroke occurs when blood flow is interrupted or greatly reduced in a localized area of the brain. Without blood to supply oxygen or nutrients to the brain, cells begin to quickly die off. Risk factors include high blood pressure, high cholesterol, smoking, diabetes, family history and old age. Depending on the part of the brain affected, a stroke may cause loss of memory, speech impairment, reasoning ability, paralysis, coma or death. A stroke is also known as a cerebrovascular accident (CVA) or a brain attack.
There are two kinds of stroke: ischemic or hemorrhage.
Cerebral thrombosis or cerebral embolism (acute ischemic stroke) is caused by blood clots that block an artery’s blood supply to the brain - either in the brain itself or in the neck. Cerebral thrombosis and cerebral embolism account for 70 to 80% of all strokes.
Subarachnoid hemorrhage and intracerebral hemorrhage occur when a blood vessel bursts around or in the brain. Hemorrhage or bleeding can occur when a blood vessel breaks open, either from excessive internal pressure or from head trauma. Vessels most likely to break are those with innate defects, such as an aneurysm. An aneurysm is a bulge or weak spot in the arterial wall.
Transient ischemic attacks or TIAs (mini-strokes) are a predictor in about one-third of stroke cases. TIAs occur when a blood clot temporarily blocks an artery, and part of the brain doesn’t receive a supply of blood it needs. The symptoms occur rapidly and last a short time - between one and five minutes total - but unlike stroke, when it ceases, there is no brain injury. TIAs are important predictors of an impending major stroke.
Immediate medical treatment to the symptoms listed below can prevent a disabling stroke from occurring. If you experience any of these symptoms, please seek medical treatment immediately by calling 911 or going to the Emergency Department.
- Sudden weakness, numbness or paralysis of the face, arm or leg, especially on one side
- Loss of speech or trouble talking
- Sudden loss of vision, particularly in one eye
- Sudden, severe headache
- Trouble walking: unexplained dizziness or loss of balance, especially if experiencing any other symptoms