Fig 2.

Injection of right external carotid artery (A and B) and left external carotid artery (C and D) demonstrates the reconstitution of the distal internal carotid artery by branches of the internal maxillary arteries, middle meningeal arteries, deep temporal arteries, artery of the foramen rotundum, ascending pharyngeal arteries, and collaterals of the occipital artery. Injection of the left vertebral artery (E and F) shows the discontinuation between the vertebral arteries and the abnormally dilated proximal basilar artery with collateral branches mainly from the left vertebral artery.