AN OBSERVATION OF THE ARTERIAL SYSTEM OF THE CHINESE BRAIN Ⅳ. THE INTRACRANIAL PORTION OF THE VERTEBRAL ARTERIES AND THE BASILAR ARTERY / 解剖学报

ABSTRACT

The intracranial portion of the vertebral arteries and the basillar artery of 103 Chinese (80 adults and 23 children) brains have been studied. The diameter of the intracranial portion of the vertebral artery on the left side is usually greater than that on the right side. The anterior spinal artery comes off mostly from the vertebral artery. It descends, slants medially and unites with the opposite artery to form a single anterior spinal artery in front of the anterior median fissure of the medulla oblongata. The vertebral artery usually gives off 1～3 medullary branches, which enter the medulla oblongata mostly through the posteriolateral sulcus. The blood supply of medulla oblongata has been discussed.In 57.50?5.53% of the adults, the union of the right and left vertebral arteries to form the basilar artery was found at the level of pons, while in children, 47.83?10.39% was found at the level of the lower border of pons. The labyrinth arteries arise mostly from the anterior inferior cerebellar arteries (77.50?2.95), and in rare cases, from the superior cerebellar or vertebral arteries. The pontine branches coming off from each side of the basilar artery are usually 3～4 in number.