Cerebral blood supply: Part 2

Learn this with friends

ScienceHealth and medicine4:326 check-ins

About this video

This video maps the blood supply of the brain by vascular territory. The anterior, middle and posterior cerebral arteries each supply a region of the cerebrum, with the middle cerebral artery covering most of the lateral surface. It then covers the cerebellar arteries, the superior, anterior inferior and posterior inferior, plus the pontine branches and the anterior spinal artery that supply the brainstem.

You'll be able to

  • name the three main arteries that supply the cerebrum and the lobes each one serves.
  • name the three cerebellar arteries and the vessel each one branches from.
  • explain why the pontine branches and the anterior spinal artery are linked to the brainstem.

Key words

Vascular territory
The area of brain tissue that a particular artery supplies with blood.
Cerebrum
The large upper part of the brain that is divided into the frontal, parietal, temporal and occipital lobes.
Basilar artery
The artery at the base of the brain from which the superior and anterior inferior cerebellar arteries and the pontine branches arise.
Pontine branches
Arteries branching from the basilar artery that mainly supply the pons, a part of the brainstem.
Anterior spinal artery
A vessel that runs down the front of the spinal cord and also supplies a bit of the brainstem.
Transcript

- So we know that the cerebrum is primarily supplied by the anterior cerebral artery, the middle cerebral artery, and the posterior cerebral artery. So let's actually draw out on the surface of these brains here, let's draw out their supply areas, their vascular territories.

So let me orient you here, so here's that side view of the brain again, looking directly from the side. And this brain here, this is just one half of the brain. So what we've done is essentially we've cut away one half of a brain. Right? And we're looking at the remaining half.

>From this side. So remember we said, your anterior cerebral artery's gonna do right between these lobes, remember we said the anterior cerebral artery is here, so it's gonna serve the inside parts of the lobes, right? So your anterior cerebral artery it's gonna serve blood to the inside part of the medial part of your frontal lobe, as well as just a little bit on the outside as well.

Sort of like a little bit of spillover from the blood supplying the medial part of the frontal lobe. Now your middle cerebral artery is responsible for doing a lot of the lateral part of your brain. The outside part of your brain. So it's gonna do most of the lateral part of your frontal lobe, it's gonna serve blood to it.

It's gonna supply a lot of the lateral aspect of the parietal lobe. It's gonna supply a little bit of the occipital lobe, and it's gonna supply a lot of the temporal lobe, all laterally, okay? So you're not really going to see too much middle cerebral artery supply on the inside part, the medial part of your brain, except you might see a little bit, sort of a spillover at the edge of this temporal lobe, you might see a little bit right about there.

And now the posterior, the posterior cerebral artery. The posterior cerebral artery's gonna do the rest of the lateral aspect of the cerebrum. So that's some of the parietal lobe, most of the occipital lobe, and a fair chunk of the temporal lobe. So that's the occipital lobe on the outside and the inside, and that bit of the temporal lobe on the outside and the inside.

All right, so that's the major blood supply to the cerebrum, let's now look at the blood supply to the cerebellum. All right, so let's make the theme, our colors scheme of the cerebellar arteries, let's make it this nice little purple here, purple and pink. So the main arteries of the cerebellum are the superior cerebellar, which I'll draw in purple here, superior cerebellar.

So they're actually coming off the basilar artery and wrapping backwards to reach the cerebellum. And it's really tough to see on this anterior view, but you'll just have to trust me that it's there. The next one is the anterior inferior cerebellar artery, so I'll draw that in this darker purple here, and again, that's coming off the basilar artery.

You can just see how important this basilar artery is. And last we have our posterior inferior cerebellar. And that one comes off the vertebral artery and serves the bottom bit of the cerebellum. It's a little bit tough to see on the anterior view so I won't draw it in there.

So those are the three major arteries of the cerebellum. See when you group them like this, I find it's a lot easier to sort of digest it all. All right, and finally we have the brain stem. So let's use green for our theme, our color scheme for the brain stem arteries.

So for the brain stem we have these branches that come off the basilar artery called the pontine branches. As a group, we'll just consider them the pontine branches. And they're called the pontine branches because they serve mainly the part of the brain stem called the pons.

And here they are on the anterior view. Last, we have the anterior spinal artery. Okay, so the anterior spinal artery sort of runs between it actually is connected to both the vertebral arteries and it runs down the spinal cord, the front of the spinal cord. Hence the name, anterior spinal artery.

So the anterior spinal artery, even though it's called the spinal artery, it still supplies a bit of the brain stem. So all of these, everything I just showed you, these are the main blood vessels of the brain.

Video © Khan Academy, used under CC BY-NC-SA. Watch on Khan Academy. Puzzicle is not affiliated with Khan Academy.