(1.28)

Now we'll follow the course of the other major artery to the brain, the vertebral artery. As we've seen, seen, the vertebral artery arises from the subclavian artery in the root of the neck. It runs straight upwards, and disappears to pass through the opening in the transverse process of the sixth cervical vertebra.

To follow its course we'll remove all the neck muscles, and the tissues between the transverse processes. The vertebral artery runs upwards through the transverse processes of the upper six cervical vertebrae. Here's the vertebral artery. The two vertebral arteries pass through these openings in each vertebra.

After passing through the transverse process of the atlas, the artery turns backwards, and then medially, to pass through the atlanto-occipital membrane and the dura, just below the foramen magnum, which is here.

To follow the vertebral artery we'll divide the cranium along this line, and remove the brain. Here are the two vertebral arteries passing through the dura. The vertebral arteries join together, forming this large artery, the basilar artery, which runs upwards and forwards above and behind the basilar part of the occipital bone.