The vertebral arteries, along with the basilar artery and their branches, constitute which vascular system?

• A. Cerebral arterial system
• B. Vertebrobasilar system
• C. Common carotid system
• D. Subclavian system

Answer: (B)

The correct answer is the vertebrobasilar system, which is the vascular system formed by the vertebral arteries and the basilar artery and their branches. This system primarily supplies blood to the posterior part of the brain, including the brainstem, cerebellum, and the occipital lobes of the cerebrum. Understanding this system is crucial for recognizing how blood flow is distributed throughout the brain and for diagnosing and managing cerebrovascular diseases that affect this region.

The vertebral arteries arise from the subclavian arteries and join to form the basilar artery at the base of the brain. Their branching provides essential circulation to key structures. This system is distinct from the cerebral arterial system, which encompasses the internal carotid arteries and their branches, primarily supplying the anterior and middle cerebral territories.

The common carotid system refers generally to the major arteries supplying the head and neck, and the subclavian system involves branches of the subclavian artery that provide blood to the arms and other areas, but it does not specifically pertain to the posterior circulation of the brain as the vertebrobasilar system does. Thus, understanding these distinct systems highlights the specialized pathways of blood supply critical for neurological function.