Middle Cerebral Artery Stroke Causes, Symptoms, and Treatment

A stroke is a medical emergency that occurs when blood flow to a part of the brain is interrupted as a result of a ruptured or blocked blood vessel. Brain cells that do not receive a constant supply of oxygenated blood can die, which can cause permanent damage to the brain.

A middle cerebral artery (MCA) stroke is one of the most widely recognized large vessel strokes. A stroke is usually named by the injured part of the brain or by the blocked blood vessel, and an MCA stroke is an interruption of blood flow to the areas of the brain that receive blood through the middle cerebral artery. These regions include the frontal, parietal, and temporal lobes as well as the internal capsule.

Middle Cerebral Artery Stroke Symptoms

Symptoms of MCA stroke are consistent with the symptoms people usually associate with strokes, such as weakness and/or numbness on one side, facial droop, and difficulties with speaking.

The arteries of the brain
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If the middle cerebral artery itself is blocked, then the result is a large-vessel stroke that affects the entire middle cerebral artery territory, which is every region of the brain that receives blood through the middle cerebral artery.

A middle cerebral artery stroke (MCA) stroke may cause language deficits, as well as weakness, sensory deficits and visual defects on the opposite side of the body.

If only a small branch of the middle cerebral artery is blocked, then a small-vessel stroke results, impacting a small section of the middle cerebral artery territory. This is often less serious.


MCA strokes are generally embolic as opposed to thrombotic. This means that usually a middle cerebral artery stroke is caused by a blood clot that traveled from elsewhere in the body, typically from the heart or from the carotid artery, and lodged in the middle cerebral artery, blocking blood flow.

There are a number of risk factors for MCA stroke, including heart disease, carotid artery disease, and the risk factors that can cause a stroke in any location in the brain, such as high cholesterol, hypertension, and diabetes.

Middle Cerebral Artery Anatomy

There are two middle cerebral arteries: the right middle cerebral artery and the left middle cerebral artery. The right and left middle cerebral arteries are vital blood vessels that branch off from the right and left internal carotid artery.

Each internal carotid artery is a branch of either the right or left common carotid artery, which are large blood vessels located on each side of the neck.

The right and left common carotid arteries are normally mirror images of each other, and each common carotid artery divides into an external carotid artery and an internal carotid artery.

Then, within the skull, the internal carotid artery further divides into several arteries that supply blood to the brain, the largest of which is the middle cerebral artery. The left and right middle cerebral arteries each supply a significant portion of the brain with oxygen-rich and nutrient-rich blood.

Function of the Middle Cerebral Artery

Arteries in the brain carry blood to deliver oxygen and nutrients to the brain. The different arteries are structured like pipelines that travel to different regions of the brain.

Each artery supplies a different section of the brain. A section of the brain that receives blood from a particular artery is referred to as the 'territory' of that artery.

The middle cerebral arteries supply a large territory in the brain that includes the temporal lobe, the parietal lobe, the internal capsule, and a portion of the frontal lobe. If blood flow to these arteries is impaired, the jobs normally carried out by these areas of the brain become compromised.

Diagnosis, Treatment, and Recovery

Although MCA stroke is among the most easily recognized types of stroke, you may need to undergo imaging tests to confirm the diagnosis.

Because an MCA stroke may be a large stroke, the short-term situation is handled with the utmost care. Some people who experience an MCA stroke are candidates for urgent treatment with tissue plasminogen activator (TPA) or blood thinners, while others may need careful fluid management and close observation.

A Word From Verywell

If you or a loved one has experienced an MCA stroke, then your recovery may take some time, particularly if the entire MCA was blocked, resulting in a large stroke.

Long-term recovery and rehabilitation may take months or even years. However, even very serious strokes can result in good recovery, and most people who experience MCA strokes are able to regain some function after the stroke.

Frequently Asked Questions

  • What is a middle cerebral artery stroke?

    A middle cerebral artery stroke occurs when the middle cerebral artery (the largest branch of the internal carotid artery) is blocked. The middle carotid artery supplies parts of the brain responsible for movement and feeling in the trunk, limbs, and face.

  • What are symptoms of a middle cerebral artery stroke?

    Middle cerebral artery (MCA) strokes cause the same symptoms that people commonly associate with any stroke, namely:

    • Unilateral (one-sided) weakness and/or numbness
    • Unilateral facial drooping
    • Unilateral vision changes
    • Difficulty speaking
    • Loss of ability to understand or express speech
  • What causes a middle cerebral artery stroke?

    A middle cerebral stroke can either be hemorrhagic (caused by a brain bleed) or ischemic (caused by a blockage). Older age, genetics, race, high blood pressure, smoking, obesity, and diet contribute to both. Risk factors for an ischemic stroke also include high cholesterol, diabetes, coronary artery disease, heart failure, and atrial fibrillation.

  • How is a middle cerebral artery stroke diagnosed?

    The diagnosis starts with either a computed tomography (CT) or magnetic resonance imaging (MRI) scan of the brain, followed by a CT or MR angiogram of the head and neck. Lab tests may be performed as well as other diagnostic procedures such as an electrocardiogram (ECG) or thoracic echocardiogram.

  • How do you treat a middle cerebral artery stroke?

    In the event of an ischemic stroke, an intravenous drug called tissue plasminogen activator (TPA) is used to break up the clot blocking the artery; in some cases, catheters and stents may be used to remove the clot and restore blood flow. Hemorrhagic strokes usually require surgery to relieve intracranial pressure caused by bleeding

  • How do you know if you are having a stroke?

    The acronym BE FAST is often used by health educators to describe stroke symptoms affecting balance, eyes, face, arm, speech, and time. Call 911 or seek emergency care if you or a loved one experiences:

    • Sudden loss of balance on one side
    • Vision changes in one eye or double vision
    • One-sided facial drooping
    • Loss of function or sensation in one arm
    • Slurring of speech
    • Trouble finding a word or getting words out
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