Vascular Supply to the Brain Flashcards
Which arteries is the arterial supply primarily supplied by?
Vertebral & internal carotid arteries
The vertebral arteries enter via ______ _____ and ascend onto the surface of _____ to the lower border of the ____
Foramen magnum, medulla, pons
The vertebral arteries unite to form what structure?
Basilar artery
Where do the internal carotids enter via?
Carotid canal in base of skull.
Right and left vertebral arteries are branches of what arteries?
Subclavian arteries.
The vertebral arteries travel through what structure of the vertebrae?
Transverse foramina beginning @ C6
What are the 3 branches of the vertebral arteries?
- Anterior inferior cerebellar artery
- Superior cerebellar artery
- Posterior cerebral arteries
What does MIPs stand for? Why are they useful?
Maximum intensity projection images
They’re useful when wanting to visualise a lot of vascular structures on a single image.
The basilar artery bifurcates to form what arteries?
2 posterior cerebral arteries.
What do the posterior cerebral arteries supply?
Occipital lobe of brain
Basilar artery is the site of what?
Most common aneurysm in brain - berry aneurysm.
The internal carotid arteries commence at the bifurcation of _____ _____ at the level of T_
Common carotid
T4
Where does the internal carotid artery lie to the external carotid artery?
Initially lies lateral too ext. carotid but quickly passes medial and posterior?
What 2 structures does the internal carotid artery ascend with?
Internal jugular vein & vagus nerve
Where does the internal carotid artery enter the skull?
carotid canal in petrous temporal bone
Are there branches of the internal carotid in the neck?
No
What does the internal carotid artery divide into at the end? (terminal branches)
Anterior & Middle cerebral arteries?
What artery originates from the internal carotid after the emergence from cavernous sinus?
Ophthalmic artery
Where is the Circle of Willis located?
Interpeduncular cistern
What does the circle of willis enclose?
Optic chiasm & infundibulum
Which is the smallest of the terminal branches of the ICA?
Anterior cerebral artery
Where does the anterior cerebral artery enter the brain?
Longitudinal interhemispheric fissure
What structures does the anterior cerebral artery supply? (6)
- Medial surface of frontal & parietal lobes.
- Corpus collosum (genu)
- Nucleus caudatus (head)
- Internal capsule (ant. limb)
- Putamen, Globus pallidus
- External capsule.
What structure does the ant. cerebral artery travel along the upper surface of?
Corpus collosum.
The anterior cerebral artery divides into what 3 parts?
A1, A2, A3
Where are the A1,A2,A3 segments of ant. cerebral artery located?
A1: region of optic nerve, horizontal
A2: Interhemispheric fissure, before rostrum of corpus collosum, vertical
A3: Genu of corpus collosum, distal
What 2 arteries does the A3 segment of ACA divide into?
Pericallosal artery
Callosmarginal artery
Where does the middle cerebral artery lie and what does it supply?
Lies in lateral sulcus & supplies lateral surface of frontal, parietal & temporal lobes.
Occlusion of the middle cerebral artery results in what?
Contralateral motor & sensory paralysis of face & arm
The middle cerebral artery (MCA) gives off central branches to supply ____ ___
Internal capsule
Which artery is referred to as the artery of cerebral haemorrhage?
Middle cerebral artery
What are the 4 parts of the middle cerebral artery?
M1, M2, M3, M4 segments
M1 segment travels from the Internal carotid artery to the ___ ___
lateral fissure
M2 segments is the ___ component and designates branches located inside the ____ ___
Insular
Sylvian fissure
M3 segment is ____ and denominates the branches between the top of ____ fissure & _____ cortex
Opercular
sylvian
cerebral
M4 segment is ____ & refers to arterial branches on surface of ____ ____
cortical
cerebral cortex
The posterior cerebral arteries arise from the division of which artery?
Basilar artery
Where do the posterior cerebral arteries end?
Above tentorium in calcarine sulcus.
How many segments in the posterior cerebral arteries?
4
P1 segment courses from ____ artery to the _____ ____ artery & passes over the ____ nerve
Basilar
posterior communicating
oculomotor (III)
P2 segment begins with _____ ____ artery & curves around _____ (____ cistern) to go near the ____ nerve above the _____ cerebelli
posterior communicating midbrain ambient trochlear (IV) tentorium
P3 segment travels briefly through the _____ cistern
quadrigeminal
P4 segment ends in _____ fissure
calcarine
What does the posterior cerebral artery supply? (7)
- midbrain
- thalamus
- post. limb internal capsule
- optic tract
- choroid plexus & cerebral peduncles
- splenium corpus collosum
- inferomedial temporal lobe & large part occipital lobe.
Occlusion of posterior communicating artery causes?
Blindness in contralateral visual field.
The anterior communicating artery (ACOM) arises from which artery?
Anterior cerebral artery
The ACOM demarcates the junction between what 2 structures?
A1 & A2 segments of ant. cerebral artery
The Posterior communicating artery (PCOM) originates from what?
Post. aspect of C7 segment of ICA
What does PCOM anastomose with?
Ipsilateral posterior cerebral artery
The venous drainage system is divided into 3 sections, name these.
Superficial
Deep
Dural venous sinuses
Where do the veins of the head drain into?
Dural sinuses
What structures do the dural sinuses drain into?
Jugular veins
Superficial veins of the brain drain into what?
Superior portion of cerebral cortex
The superficial veins drain into what?
Superior sagittal sinus.
Name the 3 unpaired venous sinuses
Superior sagittal
inferior sagittal
straight
Name the 3 paired venous sinuses
Transverse
Sigmoid
Cavernous
Whats the largest dural venous sinus?
Superior sagittal
Where is the superior sagittal sinus located?
Between falx cerebri & calvarium/ cranial bones
Where does the superior sagittal sinus receive blood from?
Cortical veins
What does the superior sagittal sinus become continuous with?
Right transverse sinus
Where does the inferior sagittal sinus lie?
Inferior border of falx cerebri
What veins does the inferior sagittal sinus receive from the medial surface of the hemisphere?
Cerebral veins
What structure does the inferior sagittal sinus join to form the straight sinus?
The great cerebral vein ( vein of Galen)
The union of the two ____ _____ veins forms the vein of Galen
Internal cerebral
Where is the straight sinus located?
At the junction of falx cerebri and tentorium cerebelli
Where and what does the straight sinus become continuous with?
Left transverse sinus near the internal occipital protuberance
Where does the transverse sinus lie?
In the groove of the inner surface of occipital bone, along post. attachment of tentorium cerebelli.
The transverse sinus curves down into the post. cranial fossa to follow a curved course as the ____ sinus
sigmoid
What 3 sinuses does the transverse/sigmoid sinus drain?
superior, occipital & straight
Sigmoid sinus follows an _-shaped path that loops over the ____ & ____ portions of the jugular foramen
S
petrous
mastoid
What dos the sigmoid sinus continue as when passing through jugular foramen?
Internal jugular vein
Where is the cavernous sinus located?
Each side of the body of sella turcica
Cavernous sinus receives venous blood from the ____ & ____ cerebral veins
ophthalmic
middle
What is the cavernous sinus drained by?
petrosal sinuses that drain into sigmoid sinus/jugular vein
What structure enters the cavernous sinus through foramen lacerum?
ICA
