Which portions does the vertebral artery feed?

• A. Spinal cord, cerebellum, posterior part of the brain
• B. Frontal lobe
• C. Temporal lobe
• D. Anterior spinal artery only

Answer: (A)

Vertebral arteries form the posterior circulation, delivering blood to the spinal cord, cerebellum, and the posterior part of the brain. They give rise to branches that supply the spinal cord via the anterior spinal artery (ventral two-thirds) and posterior spinal arteries, and they feed the cerebellum through the posterior inferior cerebellar arteries. The basilar artery, formed by the merging vertebrals, then sends branches to the posterior cerebral arteries, which supply the posterior brain regions such as the occipital lobe and parts of the temporal lobe. Because of this distribution, the vertebral arteries cover spinal cord, cerebellum, and the posterior brain, whereas the frontal lobes are predominantly supplied by the carotid system. The idea of “anterior spinal artery only” misses the cerebellar and posterior brain supplies.