Arterial Supply of the Brain Flashcards
Where does the common carotid artery divide into the external and internal carotid arteries?
Upper boarder of thyroid cartilage
Where does the internal carotid artery flow after the common carotid bifurcates?
Carotid canal at the base of the skull
From where do the vertebral arteries arise?
First part of the subclavian arteries
Summarise the flow of the internal carotid artery from its bifurcation to the Circle of Willis
- Enters skull through carotid canal
- Travels above foramen lacerum
- Enters cavernous sinus and travels its length
- Emerges from cavernous sinus by piercing its roof under the anterior clinoid process
- Gives off branches of the Circle of Willis
Describe the flow of the internal carotid artery inside the brain
- Curves upward under anterior clinoid process
2. Gives off ophthalmic artery (to orbit) and posterior communicating artery (joins posterior cerebral artery)
How does the internal carotid artery end?
Gives 2 terminal branches:
- Anterior cerebral
- Middle cerebral
How does the vertebral artery enter the skull?
Foramen magnum
What does internal carotid artery and vertebral artery form around the base of the skull?
Circle of Willis
What is the function of the Circle of Willis?
Ensure blockage of arterial flow in one artery can be compensated for
Through which vertebrae does the vertebral artery pass through?
C6-C1
Through which vertebrae does the vertebral vein pass through?
C7-C1
How does the Circle of Willis carry out its function?
Maintains connection between right subclavian and left common carotid
Where does the basilar artery run?
From the beginning to the end of the pons along the midline
Through which part of a vertebra do the vertebral vessels pass?
Transverse foramen
What are 3 branches of the internal carotid artery found in the Circle of Willis?
- Anterior cerebral
- Middle cerebral
- Posterior communicating artery
Describe the different arteries which form the posterior cerebral artery
- Aorta
- Subclavian a.
- Vertebral a.
- Basilar a.
- Posterior cerebral a.
How does the basilar artery form?
The unification of two vertebral arteries
What arteries supply the pons?
Pontine arteries
Where do pontine arteries arise?
Basilar artery
What two arteries does the anterior communicating artery join?
Right and left anterior cerebral arteries
What two arteries does the posterior communication artery join?
Posterior cerebral artery and the internal carotid artery
What artery supplies the upper spinal cord?
Anterior spinal artery
What artery gives the anterior spinal artery?
Vertebral artery
What 2 arteries are given from the vertebral arteries before their unification?
- Anterior spinal
2. Posterior inferior cerebellar
What 2 arteries are given from the basilar vein?
- Anterior inferior cerebellar
2. Superior cerebellar
What area of the cerebrum does the anterior cerebral artery supply?
Medial surface until parietooccipital sulcus and one in strip on superior lateral surface
What area of the cerebrum does the middle cerebral artery supply?
Lateral surface except narrow superior and inferior strips supplied by ant. and post. cerebral arteries respectively
What area of the cerebrum does the posterior cerebral artery supply?
Occipital pole and inferior surface on both medial and lateral surfaces
What artery supplied the anterior pole of the temporal lobe?
Middle cerebral artery
What are 2 ways interruptions in cerebral flow can occur?
- Haemorrhage
2. Thrombus
How can a subarachnoid haemorrhage occur?
Rupture in an artery found in the Circle of Willis
How can a extradural haemorrhage occur?
Rupture of middle meningeal artery
How can a subdural haemorrhage occur?
Rupture of cerebral veins as they enter superior sagittal sinus
