Understanding Ischemic Stroke

• Strokes are medical emergencies that occur when the blood supply to the brain is interrupted or reduced
• This deprives the brain of oxygen and nutrients, which can cause brain cells to die
• There are three main types of stroke: ischemic stroke, hemorrhagic stroke, and transient ischemic attack (TIA)

Ischemic Stroke

• Ischemic stroke is the most common type of stroke, accounting for about 87% of all cases
• It occurs when a blood vessel that supplies blood to the brain is blocked by a blood clot or other obstruction
• The blockage prevents blood from flowing to the brain, which can cause brain cells to die
• There are two main types of ischemic stroke: thrombotic stroke and embolic stroke

Thrombotic Stroke

• Thrombotic stroke occurs when a blood clot forms in a blood vessel in the brain
• This type of stroke is often caused by atherosclerosis, a condition in which plaque builds up inside the arteries
• Over time, the plaque can narrow the arteries and make them more likely to form blood clots

Embolic Stroke

• Embolic stroke occurs when a blood clot or other debris forms elsewhere in the body and travels to the brain through the bloodstream
• The blood clot then lodges in a blood vessel in the brain, blocking blood flow
• Embolic strokes are often caused by heart conditions, such as atrial fibrillation

Hemorrhagic Stroke

• Hemorrhagic stroke occurs when a blood vessel in the brain ruptures and bleeds
• The bleeding can damage brain cells and put pressure on the surrounding brain tissue
• Hemorrhagic strokes are less common than ischemic strokes, but they are more likely to be fatal
• There are two main types of hemorrhagic stroke: intracerebral hemorrhage and subarachnoid hemorrhage

Intracerebral Hemorrhage

• Intracerebral hemorrhage occurs when a blood vessel inside the brain ruptures and bleeds into the surrounding brain tissue
• This type of stroke is often caused by high blood pressure, aneurysms, or arteriovenous malformations (AVMs)

Subarachnoid Hemorrhage

• Subarachnoid hemorrhage occurs when a blood vessel on the surface of the brain ruptures and bleeds into the space between the brain and the surrounding membrane (the subarachnoid space)
• This type of stroke is often caused by aneurysms or head trauma

Transient Ischemic Attack (TIA)

• A transient ischemic attack (TIA), also known as a "mini-stroke," is a temporary interruption of blood flow to the brain
• The symptoms of a TIA are similar to those of a stroke, but they usually last only a few minutes to a few hours
• A TIA does not cause permanent brain damage, but it is a warning sign that a person is at risk of having a stroke in the future
• About one-third of people who have a TIA will have a stroke within a year

Other less common types of stroke

• Other much rarer types of stroke exist
• These include:
  • Stroke associated with other conditions
  • Cryptogenic stroke
  • Spinal cord stroke
  • Brainstem stroke

Stroke associated with other conditions

• Stroke-like symptoms may occur in a range of other conditions
• These include:
  • Migraine with aura
  • Seizures
  • Brain tumors
  • Infections
  • Some genetic and metabolic disorders

Cryptogenic stroke

• Cryptogenic stroke describes a stroke where the cause is unknown
• Despite thorough investigation, no cause is identified
• It accounts for a significant proportion of ischemic strokes

Spinal cord stroke

• This is a rare type of stroke that affects the spinal cord rather than the brain
• It can lead to weakness or paralysis, sensory loss, and bowel or bladder dysfunction

Brainstem stroke

• Brainstem stroke affects the brainstem, which controls vital functions like breathing, heart rate, and consciousness
• Can cause a wide range of symptoms, including:
  • Vertigo
  • Double vision
  • Difficulty swallowing
  • Weakness

Risk factors for stroke

• Several risk factors can increase a person's risk of having a stroke
• Some of these risk factors can be modified, while others cannot
• Modifiable risk factors:
  • High blood pressure
  • High cholesterol
  • Smoking
  • Diabetes
  • Obesity
  • Physical inactivity
  • Unhealthy diet
  • Atrial fibrillation
• Non-modifiable risk factors:
  • Age
  • Family history
  • Race
  • Sex

Symptoms of stroke

• The symptoms of a stroke can vary depending on the type and severity of the stroke, as well as the area of the brain that is affected
• Common symptoms of stroke include:
  • Sudden numbness or weakness of the face, arm, or leg, especially on one side of the body
  • Sudden trouble speaking or understanding speech
  • Sudden trouble seeing in one or both eyes
  • Sudden dizziness, loss of balance, or coordination
  • Sudden severe headache with no known cause

Diagnosis of stroke

• If a person is suspected of having a stroke, it is important to seek medical attention immediately
• A doctor will perform a physical exam and ask about the person's symptoms and medical history
• The doctor may also order tests, such as a CT scan or MRI scan, to determine the type and location of the stroke
• These scans help visualize the brain and identify any bleeding or blockages

Treatment of stroke

• The treatment for stroke depends on the type of stroke and how quickly treatment is received
• For ischemic stroke, treatment may include:
  • Thrombolytic drugs (such as tPA) to dissolve blood clots
  • Mechanical thrombectomy to remove blood clots
  • Antiplatelet drugs (such as aspirin) to prevent blood clots from forming
  • Anticoagulant drugs (such as warfarin) to prevent blood clots from forming
• For hemorrhagic stroke, treatment may include:
  • Medication to control blood pressure
  • Surgery to remove blood from the brain or repair damaged blood vessels
  • Endovascular procedures to repair damaged blood vessels
• In addition to medical treatment, people who have had a stroke may also need rehabilitation to help them regain lost function
• Rehabilitation may include:
  • Physical therapy to improve movement and coordination
  • Occupational therapy to help with daily living skills
  • Speech therapy to improve communication skills

Prevention of stroke

• There are several things that people can do to reduce their risk of having a stroke
• These include:
  • Control high blood pressure
  • Lower cholesterol
  • Quit smoking
  • Manage diabetes
  • Maintain a healthy weight
  • Get regular exercise
  • Eat a healthy diet
  • Treat atrial fibrillation