MICROANATOMY OF THE MIDDLE CEREBRAL ARTERY / 解剖学报

ABSTRACT

The middle cerebral artery and its branches were examined in 110 adult and child brains under 6-40 magnification. The following results were obtained.The main stem of the left middle cerebral artery was larger and longer than that of the right. The anomalies of the middle cerebral artery occurred less frequently than anomalies of the other major intracranial arteries. In this study, only one case of duplication of the middle cerebral artery was encountered.The patterns of the branching of the middle cerebral artery could be classified into 3 types. Double trunk type was the most common one, occurred in 76.37?2.86％. Single trunk type and triple trunk type occurred in 12.73?2.24％ and 10.90?2.10％ respectively. The latter two types could be further classified into some subtypes.The cortical branches of the middle cerebral artery consisted of frontalis orbitalis, precentralis, centralis, postcentralis, parietalis inferior, temporalis polaris, temporalis anterior, temporalis media, temporalis posterior and gyri angularis arteries. Each of these branches were usually 1～2 in number, and could originate independently or in common trunk with other branches. The average outer diameter of these branches were larger than 1.0 mm, except the temporalis polaris artery.The central branches of the middle cerebral artery consisted of medial perforating arteries and lateral perforating arteries. The medial perforating arteries were short, small, and 2-3 in number. They usually originated from the main stem of the middle cerebral artery at right angle, and then ascended to penetrate the brain through the anterior perforated substance. The lateral perforating arteries were 2～3 in number too, but they were larger than the medial perforating arteries. They originated at an acute angle from the main stem of the middle cerebral artery, or from a point of division of the middle cerebral artery, and from one of the cortical branches of the middle cerebral artery. Immediately after arising from the middle cerebral artery, they always passed medially and upward in a recurrent direction to the parent vessel after which they turned upward and laterally to penetrate the anterior perforating substance.The clinical significances of the middle cerebral artery and its branches were briefly discussed.