Ischemic strokes account for the majority of strokes.
Treatment depends on the time since symptoms began, the location of the blockage, imaging results, and the patient's medical circumstances. Some eligible patients may receive clot-dissolving medication or undergo a procedure to remove the clot.
Hemorrhagic stroke: When a blood vessel ruptures
A hemorrhagic stroke occurs when a blood vessel in or around the brain ruptures and causes bleeding.
The blood can damage nearby brain tissue and increase pressure inside the skull.
Possible causes include long-standing high blood pressure, certain aneurysms, vascular abnormalities, and other conditions affecting blood vessels.
Symptoms may include sudden severe headache, vomiting, weakness, speech difficulties, confusion, seizures, or loss of consciousness.
Treatment may involve controlling blood pressure, managing pressure inside the skull, treating the source of bleeding, or performing surgery or another procedure when necessary.
Transient ischemic attack: A warning that should never be ignored
A transient ischemic attack occurs when blood flow to part of the brain is briefly interrupted and symptoms resolve.
A person may experience facial drooping, arm weakness, speech problems, or temporary vision loss before returning to normal.
Because the symptoms disappear, some people assume that nothing serious happened.
But a TIA can be a warning that a more serious stroke may occur. Urgent assessment is necessary to identify the cause and reduce future risk.
The person should not wait for another episode before seeking help.
Chapter 6: What Happens Inside the Brain During a Stroke?
The brain controls movement, speech, memory, emotions, sensation, and many automatic functions that keep the body working.
Different regions are responsible for different tasks. When blood flow is interrupted or bleeding damages brain tissue, the effects depend partly on which area is affected.
This explains why two people can experience very different symptoms even when both have suffered a stroke.
The brain needs a constant supply of oxygen
Brain cells require a continuous supply of oxygen and glucose carried by the blood.
When an artery becomes blocked, the affected region receives less oxygen. Brain cells begin to lose their ability to function normally, and some may become permanently damaged.
The body cannot simply replace all damaged brain cells immediately. Although the brain has some ability to reorganize and adapt during recovery, the extent of recovery depends on several factors, including the location and severity of the injury.
Why every minute matters
The longer blood flow remains interrupted, the greater the risk of permanent brain injury.
This is why emergency treatment is time-sensitive. Doctors need to determine when symptoms began, perform brain imaging, and establish whether the stroke is caused by a blockage or bleeding.
The treatments for these two types of stroke can be very different. A medication that dissolves a clot may be appropriate for certain ischemic strokes but could be dangerous in a hemorrhagic stroke.
That is why a person should never try to treat a suspected stroke at home.
Why the affected brain region changes the symptoms
A stroke affecting areas responsible for movement may cause weakness or paralysis. Damage to language-related regions may affect speaking or understanding. A stroke involving visual pathways may cause vision loss, while damage to areas involved in balance can make walking difficult.
Some strokes affect several functions at once.
Even a relatively small injury can have a significant impact if it occurs in a critical region of the brain.
This is one reason doctors use imaging and neurological examinations to assess each patient rather than judging the severity of a stroke by one visible symptom.
Chapter 7: What to Do If You Suspect a Stroke
Recognizing the symptoms is only the first step. Knowing how to respond can also make a major difference.
If someone suddenly develops facial drooping, weakness on one side, difficulty speaking, unexplained vision loss, severe loss of balance, or another possible stroke symptom, treat it as an emergency.
Call emergency services immediately
Do not wait for the person to improve. Do not assume that they are too young to have a stroke.
Call the local emergency number and clearly describe the symptoms. If emergency medical transport is available, use it rather than attempting to drive the person yourself.
Emergency responders can assess the patient, provide initial care, and coordinate transport to an appropriate hospital.
Record the time symptoms began
One of the most important details is the time the person was last known to be well.
If symptoms appeared suddenly, note when they started. If the person woke up with symptoms, record when they were last seen without them.
This information can help doctors determine which treatments may be appropriate.
Do not delay calling emergency services while trying to establish the exact time.
Keep the person safe and comfortable
Help the person remain in a safe position while waiting for medical assistance.
If they are conscious, keep them comfortable and monitor their breathing and responsiveness. If they become unconscious but are breathing normally, follow the emergency dispatcher's instructions about positioning.
Do not allow them to walk around or drive.
If they are not breathing normally, follow the emergency operator's instructions and begin CPR if appropriate and if you are able.
Do not give food, drink, or medication
A stroke can affect swallowing, even when the person appears alert.
Giving food, water, or tablets may create a risk of choking or aspiration.
Do not give aspirin or other medication unless emergency medical professionals specifically instruct you to do so. This is important because the stroke may involve bleeding rather than a blocked artery.
Do not wait for symptoms to disappear
A person may suddenly feel better after experiencing weakness, speech difficulty, or vision changes.
This does not prove that the danger has passed. The episode may have been a TIA, which requires urgent assessment.
Even if the person returns to normal, emergency evaluation is still necessary.
Chapter 8: How Doctors Diagnose and Treat Stroke
When a patient arrives at the hospital with possible stroke symptoms, medical teams work quickly to determine what has happened.
The first priority is to assess the patient's condition and establish whether there is evidence of a blocked blood vessel or bleeding in the brain.
Neurological examination
Doctors may ask the patient to smile, raise their arms, speak, follow instructions, identify objects, and move different parts of the body.
They may also assess vision, sensation, coordination, awareness, and other neurological functions.
The examination helps determine which brain functions may be affected and how severe the symptoms appear.
Brain imaging
A CT scan is often used quickly to look for bleeding in the brain and other important abnormalities.
MRI may also be used in certain situations because it can provide detailed information about brain tissue and areas affected by reduced blood flow.
Additional imaging may examine blood vessels in the head and neck to identify blockages or other abnormalities.
These tests help doctors decide which treatments are safe and appropriate.
Clot-dissolving treatment
Some patients with ischemic stroke may be eligible for intravenous thrombolysis, a treatment designed to dissolve a blood clot and restore circulation.
Eligibility depends on several factors, including the time since symptoms began, imaging findings, medical history, and potential bleeding risks.
Because the treatment can cause serious bleeding complications, it must be administered under appropriate medical supervision.
Mechanical thrombectomy
In certain cases, doctors may perform a procedure called mechanical thrombectomy.
A specialist guides a catheter through a blood vessel to reach the blocked artery and remove the clot using specialized equipment.