Blood supply to Brain

Question 1

Where does the brain receive blood supply from?

Answer 1

Anterior circulation - internal carotids and supplies most of the cerebral hemispheres

Posterior circulation - vertebral arteries and supplies brainstem, cerebellum, some inferior temporal lobe and occipital lobe

Question 2

Two main branches of internal carotids supplying anterior circulation

Answer 2

Middle cerebral artery
Anterior cerebral artery

Question 3

Origins of anterior and middle cerebral arteries

Answer 3

Middle - direct continuation of internal carotid

Anterior - branch of ICA

Question 4

What does the middle cerebral artery supply and its course?

Answer 4

Cortical branches emerge from lateral (sylvian fissure) to supply lateral hemisphere (cortex and underlying white matter)
Including superior temporal, lateral parietal and lateral frontal lobes

Deep branches (lenticulostriate arteries) supply deep grey matter structures including lentiform nucleus (basal ganglia), caudate (caudate +putamen = dorsal striatum) and internal capsule

Question 5

Two divisions of middle cerebral artery

Answer 5

Cortical branches

Deep/lenticulostriate arteries

Question 6

Structure of anterior cerebral artery

Answer 6

L and R communicate/anastomose in midline with each other via the anterior communicating artery

Question 7

Course of anterior cerebral artery

Answer 7

Loop over corpus callosum and send branches to adjacent cortex

Question 8

What does anterior cerebral artery supply?

Answer 8

Cortical branches supply medial aspect (midline) of frontal and parietal lobe (BUT NOT occipital)

Also branches to corpus callosum

Question 9

What is the main midline vessel formed by confluence of vertebral arteries?

Answer 9

basilar artery

Question 10

What does terminal bifurcation of basilar artery form?

Answer 10

Posterior cerebral artery

Question 11

What does the posterior cerebral artery supply?

Answer 11

Occipital lobe
Inferior temporal lobe
Thalamus - via thalamoperforator and thalamogeniculate branches

Midbrain

Question 12

Does the anterior and posterior circulation of the brain connect?

Answer 12

Yes - posterior communicating arteries connect (branch off posterior cerebral)

Question 13

Major branches of basilar artery (anterior to posterior/top to bottom branching wise)

Answer 13

Posterior cerebral artery (terminate bifurcation)

Superior cerebellar arteries

Pontine arteries

Anterior inferior cerebellar arteries

Question 14

What does the superior cerebellar artery supply?

Answer 14

Superior cerebellum and midbrain

Question 15

What do the pontine arteries supply?

Answer 15

Pons - including the descending corticospinal tract fibres

Question 16

What do the anterior inferior cerebellar arteries supply?

Answer 16

Antero-inferior aspect of cerebellum

Lateral pons

Question 17

Two key branches of vertebral arteries

Answer 17

Anterior spinal arteries

Posterior inferior cerebellar arteries (which then can form posterior spinal arteries or these can come straight off vertebral arteries)

Question 18

Anterior spinal arteries supply and course

Answer 18

Converge in midline to supply anterior 2/3 spinal cord
Inc:
Ventral horns of spinal cord
Corticospinal tract
Spinothalamic tracts

Question 19

Posterior inferior cerebellar arteries supply and course

Answer 19

Postero-inferior cerebellum and posterior 1/3 spinal cord
Including dorsal column, most of dorsal horn

Question 20

Effects of anterior spinal artery occlusion

Answer 20

Loss of spinothalamic tract function below - bilateral

Question 21

Effects of posterior spinal artery / posterior inferior cerebellar artery occlusion

Answer 21

Loss of dorsal column functions below - bilateral

Question 22

Effects of lenticulostriate artery stroke

Answer 22

Basal ganglia affected - parkinsonian effects

Internal capsule - motor stroke as contains descending motor neurones

Question 23

Strokes involving anterior cerebral artery effects

Answer 23

Supplies midline structures - homunculus affected medially
So going to get lower limb effects