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In order to understand stroke,

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you need to understand the major vessels.

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So, we're going to review some of the basic normal

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vascular anatomy.

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So, this is a CTA of the head and neck,

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and starting inferiorly and going superiorly,

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obviously, you have the aortic arch,

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and then you have the brachiocephalic artery,

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right subclavian artery,

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right common carotid artery.

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Then you've got the left common

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carotid artery going up,

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and then the left subclavian artery going up.

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So, those are the major arch vessels.

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And then, we're going to just follow

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on the right and left,

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you now have the bilateral common carotid arteries,

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and they branch into the external carotid

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artery and the internal carotid artery.

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And usually, the internal carotid artery is posterolateral.

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And then, you can look at the branches

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of the external carotid artery are the superior thyroidal

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and the lingual branch and the facial branch.

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And then, you're going to get the ascending pharyngeal.

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And then if you go up a little more,

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you're going to get the occipital artery.

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And then, you want to follow the internal carotid artery.

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It doesn't have any other branches in

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the neck, things are symmetric.

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So you're going to see the same thing on the other

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side. And then extending intracranially,

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you have the vertical and horizontal petrous

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portions of the internal carotid artery,

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the lesser segment,

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the cavernous internal carotid artery,

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the klinoid segment,

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where the ophthalmic artery comes off.

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It's called the ophthalmic segment.

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And above that is the communicating segment,

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where you have the posterior communicating artery

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and the anterior choroidal artery coming off.

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So the three major branches of the internal

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carotid artery are the ophthalmic,

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the posterior communicating artery,

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and the anterior choroidal artery.

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Then as you go more superiorly,

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the.

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Internal carotid artery branches into the anterior

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and middle cerebral arteries.

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And if you look at the middle.

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Cerebral artery,

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this is the MCA stem or the one branch.

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And then typically, if you go inferiorly,

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there's an anterior temporal artery coming off.

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So that's this little artery right here.

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And then you branch into the superior and inferior

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divisions, or anterior and posterior divisions.

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And the superior division goes up and supplies

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the frontal branches of the MCA.

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The inferior division goes more posteriorly and

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supplies the more posterior temporal

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and parietal branches of the MCA.

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The superior division usually supplies the motor.

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Sensory strips as well.

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And then coming off the MCA stem.

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These little branches called the lenticulostriate

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branches that supply most of the basal ganglia.

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And then if you go medially,

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you have the ACA and the a one branch is the

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segment between the top of the ICA and

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the intercommunicating artery,

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which connects both sides.

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And then you have little branches

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coming off the ACA also,

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which are the medial lenticulostriate

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and typically supply the caudate head.

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And then the anterior cerebral artery goes up,

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and it branches into the two.

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Major branches,

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the pericallosal artery that goes over the corpus

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callosum and supplies the more posterior

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branches of the ACA.

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And the callosal marginal artery that supplies.

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The more anterior branches to the medial frontal

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branches of the anterior cerebral artery.

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And then.

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Let's look at the posterior circulation.

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The posterior circulation.

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Here's the left subclavian artery,

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and you can see the left vertebral artery.

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Usually the left vertebral artery is dominant,

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which means it's a little larger than

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the right vertebral artery.

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And then

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Many little branches come off.

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And the first segment of the vertebral artery

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is between its origin and where.

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It enters the foramina.

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So that's called the V1 segment.

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The V2 segment extends through

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the lower vertebral bodies.

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And then when you get to C2 and C1,

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and the artery curves around C2 and C1,

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that's the V3 segment.

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And then once it enters the foramen magnum,

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it's the V4 segment.

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Until you get to the vertebral vascular junction,

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and they're symmetric.

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The right vertebral artery just comes off the right

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subclavian artery. And then intracranially,

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you can see off the vertebral artery,

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you have the right posterior inferior cerebellar

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artery. You have the basilar artery.

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There are little tiny perforators that come off

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the basilar artery and supply the pons.

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And then you have the two paired

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superior cerebellar arteries.

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And then you have the posterior cerebral arteries.

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The P1 segment of the posterior cerebral artery

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is from the top of the basilar artery to where

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the posterior communicating artery comes in.

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So here's the posterior communicating artery

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coming in. So that's the P1 segment.

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The next segment is P2.

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And then at each branch point,

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I get P3 and P4, et cetera.

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So that's the posterior cerebral artery.

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And then we can look at maximal.

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Intensity projection images to again see

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you've got this anterior division,

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posterior division of the MCA,

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and you can see both PCAs coming back here.

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And when you look at the sagittal,

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you get a good view of the pericallosal branches

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and the callosal marginal branches.

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And then if you go to either side,

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you can see the posterior cerebral arteries

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coming and branching into their more.

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Superior and inferior branches.

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And same thing on the other side.

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We're going to go over the veins too.

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In young patients with good cardiac output,

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you do see these veins on the CPA,

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and you can see the septal veins,

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thalamostriate veins, internal cerebral veins,

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vein of Galen, straight sinus.

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You can see the superior sagittal sinus on the axial

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images. Again, you can see the thalamostriate veins,

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internal cerebral veins, vein of Galen, straight.

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Sinus,

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transverse sinuses, sigmoidal angle, and then.

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You'll see the sigmoid sinuses.

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Let's just review the sinuses quickly on.

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The CTA as well.

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So again, you want to make sure that they're patent.

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You can see the superior sagittal,

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there's just some arachnoid granulations here.

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You can see the cortical veins going.

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Into the superior sagittal sinus

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that are pretty symmetric.

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And you follow the superior sagittal sinus.

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Down,

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and you come to the

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transverse sinus, sigmoidal angle, sigmoid sinus,

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and then.

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Basically jugular bulb and internal jugular vein.

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And you want to follow those all the

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way down and make sure there's.

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Not thrombosis,

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which both look fine here.

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You can also look at delayed images.

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Sometimes you don't see the

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veins on the early images,

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but you'll clearly see the veins

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on the delayed images.

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So that is my whirlwind tour of

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cerebrovascular anatomy.