What is the Circle of Willis?
Anastomosis of ARTERIES along the inferior aspect of the brain to ensure cerebral perfusion
What is the Circle of Willis supplied by (2)?
1- vertebral arteries POSTERIORLY
2- internal carotid arteries ANTERIORLY
What is the pathway of the Vertebral Artery?
Right & Left Subclavian
go up superiorly throught TRANSVERSE FORAMINA of the cervical vertebrae
The Right & Left Vertebral arteries will give off branches to what (2) arteries and where is it located?
1- Anterior Spinal artery
2- Posterior Spinal artery
-which travel inferiorly along the spinal cord
The Right & Left vertebral arteries will also give off the Right & Left PICA, what does PICA stand for?
Posterior Inferior Cerebellar Artery
What does the Right and Left PICA supply?
the posterior cerebellum
the inferior cerebellum
When the Right & Left vertebral arteries merge what artery does it form and where does it lead to?
merges to form the Basilar artery
continues to the Arterial Circle
What artery does the Basilar Artery give off?
Anterior Inferior Cerebellar Artery
What does the AICA supply?
the anterior aspect of the cerebellum
the inferior aspect of the cerebellum
What artery from the Basilar Artery after AICA?
bonus question: what does that artery supply?
Labyrinthine aka Internal Acoustic Arteries
They supply the inner ear
What is the last artery to emerge from the Basilar Artery right before it enters the Circle of Willis?
Superior Cerebellar Artery
What does the Superior Cerebellar Artery supply?
superior aspect of the cerebellum
The Basilar Artery splits into terminal branches known as what?
Posterior Cerebral Arteries
What does the PCA supply?
the inferior aspect of the cerebrum and the occipital lobe
What is the occipital lobe related to?
The PCA is connect to the internal caroitd arteries via what artery?
posterior communicating arteries
Label the Following:
A- Anterior Communicating Artery
B- Anterior Cerebral artery
C- Internal Carotid Artery
D- Middle Cerebral Artery
E- Posterior Communicating Artery
F- Labrinthinae Artery
G- Posterior Cerebral Artery
H- Basilar ARtery
I- Anterior Inferior Cerebrellar Artery
J- Vertebral Artery
K- Anterior Spinal Artery
L- Posterior Inferior Cerebellar Artery
What does ICA stand for?
Internal Carotid Artery
Where does the ICA emerge from?
What are the two branches that ICA branches into?
internal and external branches
What does the ICA enter the cranium through?
What are the three terminal branches of the ICA?
1- Right Middle Cerebral Arteries (MCA)
2- Left MCA
3- Anterior Cerebral Arteries (ACA)
What does ACA stand for?
Anterior Cerebral Artery
ACA will go towards what direction(anteior/posterior) to end up win what lobe?
will course anterior toward the Frontal Lobe
What is the Right and Left ACA joined by?
Anterior Communicating Artery
What does the ACA supply (2)?
the medial portion of the frontal lobes
Supero-Medial Parietal lobes
What does MCA stand for?
Middle Cerebral Artery
What orientation does the MCA travel in the brain?
travel laterally along the cerebral hemispheres
What does the MCA supply (4)?
1- Frontal Lobe SUPERFICIALLY
2-Parietal Lobe SUPERFICALLY
3-Temporal Lobe SUPERFICALLY
What artery has the largest diameter of all the cerebral arteries?
MCA Middle Cerebral Artery
What artery is most commonly involed during a (CVA) cerebral vascular accident
Middle Cerebral Artery (MCA)
What emerges from the External carotid at the level of the mandible?
the Facial Artery
What provides the majority of arterial perfusion to the face?
When the External Carotid continues superiorly it changes it name to what?
Superficial Temporal Artery
Where does the Superficial temporal artery travel to and supply?
travels superfically to the temporal fascia and it supplies the temporal region
What is a physical difference between superficial arteries and veins?
the supericial venous drainage of the face is valve-less.
Where will the veins of the face drain into (3)?
1- INTERNAL jugular veins
2- EXTERNAL jugular veins
3- ANTERIOR jugular veins
The three facial vein drainages are internal, external, and anterior JUGULAR veins. What are the two bigger vein they eventually lead into?
Superior vena cava
what does the common carotid artery bificate into?
-internal carotid artery
external carotid artery
what does the bificated internal carotid artery lead to? and via what?
into the cranium via the carotid canal
what does the bificated external carotid artery lead into?
From the heart what is the first vessel to exit it?
the Ascending aorta with a curved aorta arch
what are the three branches left to right in the aorta arch?
brachial sphalic trunk, Left common carotid, Left subclavial
Continue this ascending path from heart to ascending aorta, arota arch, brachial sephalic trunk, (4)
it bificates into the Right common carotid and Right subclavian. The RCC bificates also into the external and internal carotid artery.
remember that the internal carotid artery goes into the skull
the external carotid artery goes into the face
***on the right side***
Continue this ascending path from the heart, ascending aorta, aorta arch, left common carotid, (2)
bificates directly into internal and external common carotid artery*** on the left side***
Continue this ascending path from the heart, ascending aorta, aorta arch, left subclavian, (1*)
bificates into *UE and vertebral artery
what is the path of the vertebral artery that branches from left subclavian. Resulting in the cranium?
Vertebral artery travels through the transverse foramina, then through the suboccipital triangle, then foramen magnum
What artery creates the posterior portion of the circle of Willis?
Posterior Cerebral artery
What is the last artery branching off the basillar artery before the Circle of WIllis?
Superior cerebellar artery
What does labarythy supply?
labarynthae of the inner ear
What is the first branch off basillar artery?
anterior inferior cerebellar arteries
what does the carotid artery pass through?
Once the vertibral arteries enter the cranium via the Foramen Magnum what happens?
They merge together
Just prior to the Vertibral arteries that are ascending into the brain converge what happens?
they give off anterior and posterior branches known as anterior and posterior spinal artery that descends back down through the Foramen Magnum AGAIN due to having to supply the total spinal cord which it travels inferiorly together along the spinal cord.
After the merge that descended out of the foramin magnum the vertibral arteries then they give off what?
right away as right and left Posterior inferior cerebellar artery aka PICA
After the Vertibral arteries gave off the right and left PICA what do they do?
merge once again further into the brain to form the Basilar artery
What vessels come before and after Labrynthin arteries
Anterior inferior Cerebellar arteries just before then after is the Superior cerebellar arteries