Blood Supply And Venous Drainage Of The Brain

Question 1

What arteries supply the brain via the base of the skull?

Answer 1

Vertebral artery and internal carotid artery

Vertebral artery is split into cervical, Atlantic and inter cranial parts (inferior to superior)

Question 2

What blood vessels supply the meninges?

Answer 2

ECA
- middle meningeal via maxillary
- meningeal via occipital
- meningeal and posterior meningeal from ascending pharyngeal

ICA
- anterior meningeal

Vertebral
- Meningeal branch

Question 3

What is the general structure that supplies the intercranial parts of the brain?

Answer 3

The circle of Willis / cerebral arterial circle

Question 4

Label the circle of Willis top right clockwise

Answer 4

Anterior communicating
Middle cerebral
Internal carotid
Bassilar
Vertebral
Anterior spinal
Anterior inferior cerebellar
Superior cerebellar
Posterior cerebral
Posterior communicating

Question 5

What 3 arteries are often blocked for a stroke to occur?

Answer 5

Anterior cerebral

Middle cerebral

Posterior cerebral

Question 6

What occurs when anterior cerebra artery occlusion occurs?

What is a determining factor in this?

Answer 6

If blockage is proximal to the anterior communicating, then collateral circulation is usually adequate, if it is distal then the following signs and symptoms usually found:

• contralateral he i paresis and hemisensory loss involving mainly leg and foot
• inability to identify objects correctly, personality changes

Question 7

What signs and symptoms may show from a middle cerebral artery occlusion?

Answer 7

Contralateral hemiparesis and hemisensory loss of face and arm

Aphasia - difficulty with language or speech

Anosognosia - lack of insight into the issue

Question 8

Signs and symptoms of a posterior cerebral occlusion?

Answer 8

Visual agnosia - difficult recognising objects

Memory impairment

Question 9

What are dural venous sinuses?

Answer 9

Endothelial lined Spaces between periostal and meningeal layers of the dura

They provide venous drainage of the brain and CSF resorption via arachinoid villi

Question 10

Label the sinuses, top right clockwise

Answer 10

Question 11

What types of haemorrhages can occur?

Answer 11

Extra/epi dural haemorrhage

Subarachinoid haemorrhage

Question 12

What occurs in an epidural / extra dural hepatoma and what artery normally is at fault?

Answer 12

Rupture of a blood vessel within the dura or outside the dura between the skull and the dura

Often caused by anterior / middle meningeal artery by the perion

Question 13

What occurs at a subarachinoid haemorrhage?

Answer 13

Ruptures vessel occurring below the arachinoid layer of the brain

Often a cerebral artery