Middle Cerebral Artery (MCA)

VESSEL PATHWAY

The middle cerebral artery (MCA) is one of the major arteries that leads to the brain. It branches off of the internal carotid artery and connects to the circle of Willis.

aorta → brachiocephalic artery (only right side) →  common carotid artery → internal carotid artery → middle cerebral artery (MCA)

Vessel pathway of MCA (starting from the aorta, source)
Vessel pathway of MCA (starting from the aorta, source)

The following are branches of the MCA:

  • Lenticulostriate artereis
  • MCA superior division
  • MCA inferior division
Important branches of the MCA and their anatomical locations (source)
Important branches of the MCA and their anatomical locations (source)
FUNCTION

The MCA provides blood flow to a large portion of the brain’s cerebral hemispheres: the below images give a clear representation of which areas of the brain are supplied blood by this artery.

General regions supplied by MCA

Source
Source

Coronal section of regions supplied by MCA

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Source

Axial section of regions supplied by MCA

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Source
CAUSES OF INJURY

Strokes can be a common cause of injury that can involve the MCA (and result in damage to the territories it usually perfuses). In terms of the MCA, these stories are commonly thrombotic (clot forming at the direct site of the infarct, often over an atherosclerotic plaque). Embolic stroke (possibly due to atrial fibrillation) can often involve the MCA.

MRI imaging of a stroke that involves the territory of the right MCA (source)
MRI imaging of a stroke that involves the territory of the right MCA (source)
CLINICAL PRESENTATION OF INJURY

There can a be many different types of clinical presentations if the MCA is damage or the territory it supplies blood loses perfusion. These can include: 

  • Weakness/sensory loss in the face/arms (the motor and sensory cortexes that control these regions of the body are within the MCA territory)
  • Wernicke/Broca aphasia if issue resides on dominant (usually left) hemisphere.
  • Hemineglect if issue relies on non-dominant (usually right) hemisphere
  • Certain visual field defects such as upper or lower audrantic anopia can be caused by MCA infarcts.
OTHER INFO

Paralysis/sensory loss will be contralateral to the side of the MCA infarct (given that these nerves cross over to the other side in the brainstem).

Atherosclerosis usually develops in branch points of an artery, this can include the bifurcation of the middle cerebral artery in the circle of Willis.

 

Page updated: 03.14.2016