Which vessels are involved in forming the circle of Willis?

The circle of Willis is a critical arterial structure located at the base of the brain, providing a collateral circulation that ensures adequate blood supply to the cerebral hemispheres. The formation of this arterial circle involves several key vessels.

The correct answer encompasses all the arteries involved in forming this circle. Specifically, it includes the anterior communicating artery (ACOM), the anterior cerebral artery (ACA), the internal carotid artery (ICA), the posterior communicating artery (PCOM), the posterior cerebral artery (PCA), and the terminal branches of the basilar artery.

The ACOM connects the two anterior cerebral arteries, allowing for blood flow between them. The ACA branches off from the ICA and supplies the medial portions of the frontal lobes and superior medial parietal lobes. The ICA is the primary vessel that supplies blood to the anterior circulation of the brain. The PCOM connects the internal carotid artery to the posterior cerebral artery, which stems from the basilar artery. PCA supplies the occipital lobes and the inferior portions of the temporal lobes.

Collectively, these vessels form a redundant system that maintains cerebral perfusion even if one or more of the main vessels is compromised, illustrating the importance of having all these arteries involved in the anatomical integrity