Which artery is typically affected in hemispheric strokes?

The middle cerebral artery is typically affected in hemispheric strokes because it supplies a large portion of the lateral aspect of the cerebral hemispheres, including areas responsible for motor and sensory functions of the face and upper extremities, as well as language functions in the dominant hemisphere. Due to its location and the regions it supplies, occlusion or disruption in blood flow within this artery leads to significant deficits and is most commonly associated with strokes that present with symptoms affecting the hemibody.

In contrast, the anterior cerebral artery mainly supplies the medial portions of the frontal lobes and the superior medial parietal lobes, which can lead to lower limb weakness and sensory loss but is less frequently involved in hemispheric strokes. The posterior cerebral artery supplies the occipital lobe and the inferior part of the temporal lobe, affecting vision and memory but not typically the motor deficits associated with hemispheric strokes. The internal carotid artery, while crucial in supplying blood to the brain, does not represent a specific region affected by the strokes themselves; rather, it’s more of a conduit for blood supply to the main cerebral arteries.