Stroke

What Is It?

Stroke is a general term for a sudden neurological event which results in the new onset of neurological symptoms. The term is derived from the same definition as a "stroke of lightning", referring to something that occurs suddenly and without warning.

This commonly used term can refer to more than one nervous system disease. For example, it can refer to either sudden hemorrhage or cerebral infarction. However, the most common meaning of the term is to refer to cerebral infarction, due to cerebral ischemia.

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Common types:

• Cerebral Ischemia or Cerebral Infarction: Cerebral ischemia is a decrease in blood flow to a part of the brain. If the blood flow is too low or cut off completely, that part of the brain begins to die. The result is a cerebral infarction. This is by far the most common pathology, occurring much more frequently than the hemorrhagic causes of sudden neurological symptoms listed below.
• Transient Ischemic Attack (TIA): Similar in etiology to cerebral infarction but with transient symptoms that resolve within 24 hours of their onset.
• Hemorrhagic: Hemorrhage can either occur on its own from blood vessel disease, such as the examples below, or along with a cerebral infarction.
  • Aneurysmal Subarachnoid Hemorrhage: The rupture of a cerebral aneurysm leads to subarachnoid hemorrhage. This typically leads to the sudden onset of headache and/or other neurological symptoms and is one of the most common forms of brain hemorrhage.
  • Hypertensive Hemorrhage: High blood pressure (hypertension) can lead to spontaneous hemorrhage into the brain leading to the sudden onset of neurological symptoms.
  • Other Sudden Hemorrhage: Other sources of sudden hemorrhage into the brain include arteriovenous malformation, arteriovenous fistulas, cavernous malformation and Moyamoya disease.

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Return to the Cerebrovascular Disease page from the Stroke page.

Return to the Nervous System Diseases home page.

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Important Note: This site is not intended to offer medical advice. Every patient is different, and only your personal physician can help to counsel you about what is best for your situation. What we offer is general reference information about various disorders and treatments for your education.