What are the principal branches of the internal carotid artery (ICA)?

The principal branches of the internal carotid artery (ICA) include critical arteries that supply blood to various structures in the brain. The posterior communicating artery (PCOM) is one of the key branches that connect the internal carotid artery to the posterior cerebral artery. This artery plays a vital role in the cerebral arterial circle (Circle of Willis), facilitating collateral circulation and ensuring adequate blood supply to the brain.

The anatomy and function of the PCOM underline its importance, as it helps maintain cerebral perfusion, particularly in situations where one of the main vessels supplying the brain might become obstructed or narrowed. Moreover, the presence of such communicating arteries allows for extensive interconnected circulation, which is essential for brain health.

In contrast, the other options refer to branches that are not directly associated with the internal carotid artery as its principal branches. The anastomosis artery does not specifically pertain to the ICA’s anatomy; the superficial temporal artery branches off from the external carotid artery; and the lingual artery is also a branch of the external carotid artery, serving the tongue rather than the brain. Thus, the selection of the posterior communicating artery accurately identifies a principal branch of the internal carotid artery that is crucial for cerebral blood flow.