Overview

Stroke is a brain attack. It occurs when the blood supply to the brain is blocked or reduced. Blood carries oxygen and nutrients to the brain, and it removes waste products from the tissues. When there is a lack of blood flow to the brain, brain cells begin to die within minutes.

If you have suffered a stroke, your life is about to change drastically. You may be wondering how much this will affect you physically, emotionally and financially. The good news is that stroke survivors can recover with proper treatment and physical therapy. However, some people may be left with permanent disabilities.

The following are some of the major concerns that may arise during recovery:

Physical impairments: Stroke often results in physical impairments that can limit mobility and activity levels. These include paralysis on one side of the body (hemiplegia), weakness in one arm or leg (hemiparesis), loss of sensation in parts of your face or body (hemianesthesia), trouble walking (gait apraxia), problems swallowing (dysphagia) and drooling (sialorrhoea).

Emotional problems: Stroke can leave survivors feeling frustrated by their limitations and depressed because they’re no longer able to do things they once took for granted.

Blood supply of the brain

The blood supply of the brain is provided by four arteries: two internal carotid arteries (one on each side) and two vertebral arteries (one on each side). The two internal carotid arteries give rise to branches that supply the front of the brain, while the two vertebral arteries give rise to branches that supply the back of the brain.

The major branches of these vessels include:

The anterior cerebral artery supplies most of the anterior portion of each hemisphere, including much of its frontal lobe. It also supplies parts of both temporal lobes and their underlying gyri. It arises from an arch at the junction between the internal carotid artery and its first division into anterior and middle cerebral arteries (the so-called “circle of Willis”).

The middle cerebral artery supplies most of each hemisphere between its frontal and temporal lobes, as well as portions of both frontal lobes themselves. It arises from a second arch at this same junction between internal carotid artery and first division into anterior and middle cerebral arteries (the “circle of Willis”).

What is a stroke?

A stroke is a medical emergency. It occurs when blood flow to part of the brain stops, resulting in brain cell damage or death. Strokes can cause paralysis, loss of speech and memory, as well as other disabilities.

Stroke is one of the leading causes of serious illness and death in Canada. It affects more than 115,000 Canadians each year and it is the third leading cause of death after heart disease and cancer.

What happens during a stroke?

A stroke occurs when the blood supply to part of the brain is interrupted, causing brain cells to die (infarct). The areas that control movement and sensation on one side of the body are most often affected by strokes.

A clot blocking an artery will cause an infarction in the area served by that vessel because it prevents oxygen-rich blood from reaching those cells. A clot that breaks off from a diseased artery inside an artery wall and travels into another vessel will result in an embolism if it gets stuck there – this also causes a blockage but not necessarily an infarction.

What are the symptoms?

Stroke symptoms can vary from person to person. Some people have a sudden, severe headache and may have trouble speaking or understanding others. Other people may have no symptoms until the stroke has already occurred.

Symptoms of stroke vary depending on which part of the brain is affected. These are some possible symptoms:

• Sudden, severe headache that doesn’t go away
• Nausea and vomiting
• Slurred speech or difficulty talking
• Weakness or numbness in your face, arm or leg (even if the weakness is only temporary)
• Difficulty seeing out of one or both eyes (also called visual disturbances)
• Dizziness or loss of balance or coordination

What are the causes?

Strokes are caused by a disruption in the blood supply to the brain. The most common type is an ischemic stroke, which occurs when a clot forms and blocks a blood vessel in your brain. In hemorrhagic strokes, a blood vessel breaks and bleeds into the brain tissue.

Strokes can also be caused by a brain aneurysm — a bulge in one of your arteries caused by a weakness in the wall of the artery — or an arteriovenous malformation (AVM), which is an abnormal connection between arteries and veins.

A stroke can occur at any age, but it’s more likely to happen as you get older. In fact, people over age 85 have a greater chance of having a stroke than any other age group.

How is a diagnosis made for stroke?

The first step in diagnosing a stroke is to determine if you are having a stroke. This is done by asking you questions about your symptoms, physical examination, and sometimes blood tests or imaging tests.

The doctor will ask:

• When did you first experience the symptom?
• What were you doing when it occurred?
• How long did it last?
• What were the symptoms (sudden pain or numbness in face, arm or leg)?
• How much better do you feel since the attack?

The doctor will also perform a physical examination including checking your blood pressure and looking at your eyes. If possible, he may also check for other conditions that can cause similar symptoms such as high blood pressure or diabetes. In some cases, further tests may be needed such as blood tests or imaging scans to confirm if a stroke has occurred.

Stroke Recovery

Stroke recovery is a long and difficult process. It takes time and patience for the brain to repair itself after a stroke. The damage done by the stroke can cause difficulty with movement, communication and thinking.

A stroke occurs when blood flow to part of the brain stops completely or is reduced by at least 50 percent for more than five minutes. This causes an interruption in the normal blood flow that nourishes brain cells and damages them beyond repair.

Stroke affects more than 800,000 people each year in the United States alone, according to the American Stroke Association (ASA). That’s why it’s important to know warning signs of a stroke so that you can seek medical attention if needed.

Preventing another stroke

Stroke survivors often have to deal with the effects of their stroke for the rest of their lives. If you or someone you care about has had a stroke, here are some ways to help avoid another one.

Keep your blood pressure under control. High blood pressure can increase the risk of having a second stroke. People with high blood pressure should work closely with their doctors to manage it and keep it under control.

Eat right, exercise and lose weight if needed. Eating right, exercising and losing weight can also help prevent another stroke.

Limit alcohol consumption and quit smoking if you smoke. Drinking alcohol increases your risk of having another stroke, especially if you already have other risk factors such as high blood pressure or diabetes. Smoking also increases your risk of having another stroke because it causes blood clots in the brain that can lead to a stroke if they break free and travel through the bloodstream to block an artery leading to the brain (called embolism).