Strokes can be classified into several types, primarily based on their cause. Each type has distinct symptoms and underlying mechanisms. The three main types of strokes are:
1. Ischemic Stroke: This is the most common type, accounting for about 87% of all strokes. It occurs when a blood vessel supplying blood to the brain is blocked, usually by a blood clot or a buildup of fatty deposits (atherosclerosis).
Symptoms:
- Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
- Sudden confusion, trouble speaking, or understanding speech
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance, or lack of coordination
- Sudden severe headache with no known cause
2. Hemorrhagic Stroke: This occurs when a blood vessel in the brain bursts, leading to bleeding (hemorrhage) in or around the brain. Causes can include high blood pressure, aneurysms, arteriovenous malformations (AVMs), and head injury.
Symptoms:
- Sudden severe headache
- Nausea and vomiting
- Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
- Sudden confusion, trouble speaking, or understanding speech
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance, or lack of coordination
- Sensitivity to light (photophobia)
- Seizures (in severe cases)
3. Transient Ischemic Attack (TIA): Often called a "mini-stroke," a TIA occurs when blood flow to part of the brain is temporarily blocked. TIAs typically last only a few minutes and do not cause permanent damage, but they are serious warning signs of potential future strokes.
Symptoms (similar to ischemic stroke but temporary):
- Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
- Sudden confusion, trouble speaking, or understanding speech
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance, or lack of coordination
- Sudden severe headache with no known cause
Other Less Common Stroke Types:
- Embolic Stroke: A type of ischemic stroke where a blood clot or debris forms away from the brain (commonly in the heart) and is carried through the bloodstream to lodge in narrower brain arteries.
- Thrombotic Stroke: Another type of ischemic stroke where a blood clot forms in one of the arteries supplying blood to the brain.
Recognizing Stroke Symptoms:
An easy way to remember the symptoms of a stroke and to act quickly is the acronym FAST:
- Face drooping: Ask the person to smile. Does one side of the face droop?
- Arm weakness: Ask the person to raise both arms. Does one arm drift downward?
- Speech difficulty: Ask the person to repeat a simple phrase. Is their speech slurred or strange?
- Time to call emergency services: If you observe any of these signs, call emergency services immediately.
Prompt medical attention is crucial for stroke treatment and can significantly improve the chances of recovery and reduce the risk of long-term disability.