Variable Anatomy of the Middle Cerebral Artery from Its Origin to the Edge of the Sylvian Fissure: A Direct Fresh Brain Study

Abstract

The middle cerebral artery (MCA) is a major artery supplying blood to the brain and a common site of surgically treatable intracranial aneurysms. The MCA has anatomic variations that may have clinical significance. In order to investigate and document the extent of such variations, the MCA in 100 fresh brain hemispheres from 50 deceased patients, obtained from the Police Surgeon Office, Yangon General Hospital, Myanmar, was dissected and examined. Double MCA was observed in 2% of specimens. The termination patterns were bifurcation (72%), trifurcation (16%), and primary trunk (12%); early bifurcation was also observed (3%). The mean length of the main trunk (MT) was 20.6 ± 6.2 mm. The number of perforators ranged from 4 to 15 (mean = 9); most arose from the MT (96%), and the others originated at the bifurcation point (3%) and in postbifurcation divisions (1%). All of the perforators (100%) had a single branching pattern. The number of cortical branches ranged from 6 to 13 and included the orbitofrontal (98%), prefrontal (99%), precentral (95%), central (98%), temporopolar (87%), anterior temporal (89%), middle temporal (24%), posterior temporal (62%), temporo-occipital (69%), anterior parietal (88%), angular (83%), and posterior parietal (57%) arteries. Early cortical branches emerged from the MT in 52% of specimens. These data can help anatomists, radiologists, and neurosurgeons in preoperative assessment, surgical planning, and selection of surgical approach.