Through which cranial cavity does the vertebral artery enter the skull?

The vertebral artery enters the skull through the foramen magnum. This large opening at the base of the skull allows important structures, including the vertebral arteries, to pass from the spine into the cranial cavity. Once inside the skull, the vertebral arteries contribute to the blood supply of the brain, particularly forming the basilar artery, which is vital for perfusion to various brain structures.

The foramen magnum is anatomically significant as it serves as the passageway for the spinal cord, vertebral arteries, and associated structures. Understanding the anatomy of the skull and the pathways of blood vessels is crucial for professionals in vascular ultrasound and related fields, as it aids in recognizing conditions affecting cerebral circulation.