Uppslagsverket

A

Arterial circle of the brain

Circulus arteriosus cerebri

Circulus Willisi

The circular arterial loop that surrounds the underside of the midbrainand releases the arteries that supply blood to the large brain.

The arterial circle arises in the following way. The posterior cerebrum arteries, one on the hay. and one on the left. side, posteriorly are joined to each other by their common origin from the basal artery. The posterior cerebible artery forwards the posterior connecting artery that connects to the branching site of the internal carotid artery or to the very first part of the middle cerebral artery . From here, in turn, the anterior cerebrum artery departs. The two anterior cerebral arteries will be close to each other and connect to each other across the midline of the anterior connecting artery. We have come full circle!!

IT IS IMPORTANT TO KEEP IN MIND THAT THERE ARE LARGE INDIVIDUAL VARIATIONS IN THE APPEARANCE OF THE ARTERIAL CIRCLE.

It can be said that the arterial circle is supplied with blood with the help of 4 large external arteries At the front, the right and left internal carotid arteries enter the underside of the brain through a channel in the temporal bone. At the back, the right and left vertebral arteries enter the cranial cavity through the large neck hole. The two vertebral arteries merge into the basal artery.

The arterial circle then emits the 6 major cerebral arteries: hay. and we. posterior cerebrum artery, hay. and we. middle cerebrum artery as well as hay. and we. anterior cerebrum artery.

The arterial circle is considered, at least in younger individuals, to be a possible safety system whose importance becomes apparent if any of the four supplying arteries become clogged. With the help of the various connecting arteries, areas that would otherwise have been knocked out can be supplied with blood.
...