14) Arterial Supply to the Brain Flashcards
What is the basilar artery and where does it lie?
Combination of vertebral arteries in the midline
Sits in front of the pons
Where do the posterior cerebral arteries originate?
Bifurcation of basilar artery
What are the branches of the basilar artery?
Anterior inferior cerebellar artery, pontine arteries and superior cerebellar arteries
What are the branches of the vertebral arteries?
Posterior inferior cerebellar artery
Anterior spinal artery
What arteries in the brain are formed from the internal carotid arteries?
Middle cerebral, anterior cerebral and posterior communicating arteries
What vessel joins the two anterior cerebral arteries?
Anterior communicating artery
Why is the circular organisation of the arterial supply to the brain important?
Shunting of blood to areas that it is needed
Compensation in case of blockage (collateral supply)
Describe the path of the middle cerebral artery:
Run laterally over the insular cortex and emerge through Sylvian fissure onto surface of lateral hemipshere
What does the middle cerebral artery supply?
Most of the lateral hemisphere
Basal ganglia and internal capsule
Broca’s and Wernicke’s areas
Describe the path of the posterior cerebral artery:
Loops round midbrain and runs along inferior surface of posterior hemisphere
What does the posterior cerebral artery supply?
Occipital lobe and inferior surface of temporal lobe (memory)
Describe the path of the anterior cerebral artery:
Loops back over corpus callosum and runs on its superior surface
What does the anterior cerebral artery supply?
Frontal lobes and medial surface of hemispheres
What do the lenticulostriate arteries supply and where do they originate?
Originate from middle cerebral artery
Supply lentiform nucleus, striatum and internal capsule
In what condition do lenticulostriate arteries become blocked?
Lacunar infarcts
Why is it possible to get a pure motor/sensory stroke?
Motor and sensory fibres in the internal capsule are segregated so if one small branch of lenticulostriate artery is blocked may be a pure motor or sensory stroke
How are the cerebellum and brainstem supplied (general)?
Cerebellar arteries - supply brainstem as they pass over it to get to cerebellum
What is the major blood supply to spinal cord?
Anterior and posterior spinal arteries
What parts of the cord are supplied by the anterior spinal artery?
Anterior 2/3rds of the cord - corticospinal, spinothalamic and ventral horns
What parts of the cord are supplied by the posterior spinal artery?
Posterior 1/3rd of cord - dorsal columns and dorsal horns
When can the artery of Adamkiewicz become damaged?
Aneurysm repair
Which arteries supply the midbrain?
Posterior cerebral and superior cerebellar
Which arteries supply the pons?
Pontine arteries and anterior inferior cerebellar
Which arteries supply the medulla?
Posterior inferior cerebellar (lateral)
Vertebral (anterior)
Where do the spinal arteries receive blood from?
Segmental vessels from the aorta