Circle Of Willis

Question 1

Where does most of the blood flow to the brain come from

Answer 1

Thr carotid arteries in the neck

Question 2

What does the carotid artery split into

Answer 2

It splits into two - the internal and external carotid artery. The external carotid supplies blood to the face and neck. The internal carotid supplies the brain .

Question 3

After going up the brain what does the carotid artery join

Answer 3

It joins the circle of Willis

Question 4

What are the three pairs of cerebral arteries in the circle of Willis

Answer 4

• posterior cerebral arteries
• middle cerebral arteries (direct continuation of internal carotid)
• anterior cerebral arteries

Question 5

What is the anterior communicating artery and the posterior communicating artery

Answer 5

Anterior communicating artery is the small area in between the two Ls of the circle of Willis. The posterior communicating artery is the rest, bottom of the circle

Question 6

What does anterior cerebral arteries supply and what happens if stroke

Answer 6

Supply the medial and superior aspects of the frontal and parietal lobes. Stroke here may cause weakness or paralysis of the contralateral leg and sensory loss as well as behavioural changes

Question 7

What do internal carotid arteries supply and what happens if stroke

Answer 7

Supply the front part of the brain. Due to its extensive supply area there may be hemiparesis (weakness to one side of the body), sensory deficits, aphasia and visual disturbances

Question 8

What does middle cerebral artery supply and what happens in stroke

Answer 8

Supplies a significant portion of the lateral surfaces of the cerebral hemispheres of the temporal, frontal and parietal lobe. Stroke there may cause one sided paralysis, loss of vision in one half of the visual field and aphasia (only if left middle cerebral artery gets affected)

Question 9

What does posterior cerebral artery supply and what happens during stroke

Answer 9

Supplies occipital lobe and lower portions of temporal lobe. Vision problems, memory deficits and difficulty memorising faces and objects

Question 10

What does the posterior communicating artery do and what happens during stroke

Answer 10

These connect internal carotid arteries with posterior cerebral arteries. Blockage can disrupt blood flow between the left and right posterior cerebral arteries. This can cause similar effects to PCA blockage

Question 11

What is the anterior communicating artery and what happens if this suffers a stroke

Answer 11

Connects the two anterior cerebral arteries, completing the front of the circle of Willis. It allows blood to flow between the left and right side of the circle of Willis. Blockage will affect both anterior cerebral artery supply areas, causing bilateral motor and sensory deficits in the legs and cognitive or personality changes