Blood Supply To The Brain

Neuroscience


Blood supply to the brain




Aorta gives off the carotid Sub-clavian arteries give off the other
arteries, divide into the internal arteries (vertebral arteries) – supplying
& external carotid arteries- the brain – Arteries travel up through
cervical vertebra & enter skull through
Internal Carotid arteries enter the
foremen magnum
skull through carotid canal to
supply the brain.




Cervical parts of the vertebral arteries ascend
through the transverse foramina of the first six cervical vertebra.

, Neuroscience



Holes in skull the arteries pass through to get to the brain

 Carotid canal- internal carotid artery
 Foramen magnum- vertebral artery




Below: Vertebral & Internal Carotid arteries – CT angiograms




Importance of blood supply to the brain

- Accounts only 2.5% of body
- Brain receives 17% of cardiac output & 20% of Oxygen consumed
- Ischaemic strokes (85%) occur when blood clot blocks flow of blood & O2
to the brain, haemorrhage (15%)


Once arteries enter skull:

Vertebral & internal carotid arteries connect
and for cycle of vessels at base of brain ‘circle of
Willis’ - cerebral artery circle Small arterial
branches from this circle span off to supply diff
parts of brain