Brain folding shapes the branching pattern of the middle cerebral artery
Fig 4
Anatomy of the Middle Cerebral Artery (MCA).
The cortical branches of the middle cerebral arteries are depicted on this lateral view of a right hemisphere (A). As shown here, the MCA irrigates most of the lateral surface of the frontal and parietal lobe and the entire lateral temporal surface. Despite their proximity in the Euclidean space, no anastomotic vessels exist between the frontoparietal and temporal vessels and no arteries run across the Sylvian fissure. The distribution of the MCA vessels within the fissure are shown in (B). The lower trunk branches follow the superior aspect of the temporal lobe to reach the lateral subarachnoid space; the superior trunk climbs up the insular surface to make a complete turn at the top of the insular cleft. (C) and (D) show the apparent plexiform nature of the MCA branches that, on close examination, exhibit no anastomotic vessels or connections between the superior and the inferior trunk systems. (E) shows a lateral view of a right hemisphere in which the inferior frontal gyrus has been removed allowing a clear vision of the 180 degree turn of the MCA at the top of the insular cleft (arrows), the insular surface can be seen in the depth. On (F) the entire right hemisphere except for the central core and the inferior aspect of the temporal lobe has been removed. The 180˚ turn of the superior division of the MCA at the top of the insular cleft is again visible. The branches of the anterior cerebral artery are visible at the medial aspect of the left hemisphere.