overlaps circle of Willis arterial circle of Willis EHDAA:9758 EHDAA2:0000252 Wikipedia:Circle_of_Willis neuronames:1468 GAID:486 FMA:50454 UBERON:0003709 Willis circle arterial circle MESH:D002941 SCTID:362047009 cerebral arterial circle A circle of arteries that supply blood to the brain. The Circle of Willis comprises the following arteries: Anterior cerebral artery (left and right); Anterior communicating artery; Internal carotid artery (left and right); Posterior cerebral artery (left and right); Posterior communicating artery (left and right).The basilar artery and middle cerebral arteries, supplying the brain, are also considered part of the circle. systemic artery left internal carotid artery right internal carotid artery