A stroke occurs when there is a disruption or reduction in the blood supply to an area of the brain. As a result, the cells in the brain are unable to get oxygen or nutrients causing the brain cells to die. The symptoms of a stroke are dependent on the area of the brain that is affected. Symptoms of a stroke include a sudden headache, blurry vision, dizziness, slurred speech, confusion, weakness, numbness, and facial droop. It is important to seek medical attention if you have symptoms of a stroke as soon as possible to prevent complications such as permanent disability.
People over the age of 60 years old are at an increased risk for developing a stroke. Other risk factors include high blood pressure, diabetes, high cholesterol, heart disease, and a family history of stroke. Lifestyle factors such as physical inactivity, being overweight or obese, alcohol abuse, smoking, and drug use.
There are two main causes of stroke.
- Hemorrhagic stroke- A hemorrhagic stroke occurs when the blood vessels in the brain leaks or burst which damages brain tissue. People with uncontrolled high blood pressure, over treated with blood thinners, or weak areas in the blood vessels known as aneurysms are at higher risk of developing a hemorrhagic stroke.
Hemorrhagic strokes can be divided into categories based on the location of the stroke:
- Intracerebral hemorrhage- is a term used for a stroke in which the bleeding occurs in the brain.
- Subarachnoid hemorrhage- is a term used for a stroke in which the bleeding occurs in the space between the skull and the brain tissue.
- Ischemic stroke- An ischemic stroke is caused by a blocked artery in the brain. An ischemic stroke may occur when a fatty substance called plaque builds up in the blood vessels of the brain. The buildup of plaque causes the blood vessels to become narrow, and reduces the blood flow. People with heart disease, blood clotting disorders, or an injury to the blood vessels of the neck are at an increased risk of developing an ischemic stroke.
2. Ischemic strokes can be characterized in two ways.
- Thrombotic strokes- Occurs when there is a blood clot in an artery supplying blood to the brain.
- Embolic strokes- occur when a clot forms in an area of the body and travels through blood vessels. The blood vessels get stuck and interrupt the blood flow to the brain.
Transient ischemic attack(TIA)- A transient ischemic attack is also known as a mini stroke. The condition is caused by a temporary reduction in blood flow to the brain, and does not cause permanent damage. It is characterized by temporary stroke-like symptoms such as numbness and weakness typically affecting one side of the body. Other symptoms associated with a TIA include blurry vision, temporary vision loss, slurred speech, confusion, and facial droop. A TIA is often related to a partial blockage and narrowing of the blood vessels, and increases a person’s risk of a more severe stroke in the future.
If you have had an TIA or ischemic stroke in the past, you may be prescribed an antiplatelet or anticoagulant medication to reduce the risk of a recurrent stroke.