Neuro 4 - Blood Supply to the Central Nervous System

Question 1

What percentage of cardiac output goes to the brain?

Answer 1

10-20%

Question 2

What percentage of liver glucose does the brain use?

Answer 2

66%

Question 3

State the two main sources of blood supply to the brain?

Answer 3

Vertebral arteries

Internal carotid arteries

Question 4

State the major artery that the vertebral arteries branch off.

Answer 4

Subclavian Artery

Vertebral arteries pass through the transverse foramina of the cervical vertebrae and through the foramen magnum

Question 5

State the name of venous sinuses that are at the top and bottom of the falx cerebri.

Answer 5

Superior sagittal sinus

Inferior sagittal sinus

Question 6

What is the name given to the place where all the sinuses meet?

Answer 6

Confluence of sinuses

Question 7

What connects the inferior sagittal sinus to the confluence of sinuses?

Answer 7

Straight sinus

Question 8

What vessel does the inferior sagittal sinus join with to form the straight sinus?

Answer 8

Great cerebral vein

Question 9

Which sinus ascends to join the confluence of sinuses?

Answer 9

Occipital sinus

Question 10

Which two sinuses run along the temporal bone?

Answer 10

Superior petrosal sinus

inferior petrosal sinus

Question 11

Which main sinus drains into the internal jugular vein through the jugular foramen?

Answer 11

Sigmoid sinus

Question 12

Which sinus connects the confluence of sinuses to the sigmoid and superior petrosal sinuses?

Answer 12

Transverse sinus

Question 13

Which sinus run on either side of the pituitary stalk?

Answer 13

Anterior and posterior intercavernous sinuses

Question 14

Which extension of dura mater separates the cerebellum from the inferior portion of the occipital lobe?

Answer 14

Tentorium cerebelli

Question 15

Define stroke.

Answer 15

rapidly developing focal disturbance of brain function of presumed vascular origin that lasts more than 24 hours

Question 16

Define transiet ischaemic attack.

Answer 16

a rapidly developing focal disturbance of brain function of presumed vascular origin that resolves completely within 24 hours

Question 17

What percentage of strokes are caused by infarction and haemorrhage?

Answer 17

infarction: 85%
haemorrhage: 15%

Question 18

State two causes of occlusions.

Answer 18

Thrombus

Embolism

Question 19

What is the difference between a thrombus and an embolism?

Answer 19

Thrombus - formation of a blood clot

Embolism - plugging of small vessel by material carried from a larger vessel

Question 20

Describe the perfusion fields of the brain.

Answer 20

Anterior cerebral artery supplies the medial part of both hemispheres

middle cerebral artery extends laterally and emerges from the lateral fissure

supplies front 2/3 of the lateral part of hemisphere

Question 21

Describe the location of the leg in the motor and sensory homunculus compared to the arm?

Answer 21

leg is more medial

Question 22

Describe the features of a disturbance in the anterior cerebral artery.

Answer 22

Contralateral hemiplegia in leg more than arm
disturbance of intellect and executive function
loss of appropriate behaviour

Question 23

Describe the features of a disturbance in the middle cerebral artery.

Answer 23

Classic stroke
Contralateral hemiplegia in arm ARM more than the leg
contralateral hemisensory deficits
Hemianopia
Aphasia

Question 24

Describe the features of a disturbance in the posterior cerebral artery.

Answer 24

supplies occipital lobe

causes visual defects such as homonymous hemianopia and visual agnosia

Question 25

Which parts of the brain are involved in speech and understanding language?

Answer 25

Broca - speech

wernicks - understanding language

Question 26

What are lacunar infarcts?

Answer 26

small spaces in brain due to small vessel occlusion

caused by hypertension

Question 27

State 4 types of hemorrhagic stroke and their likely causes.

Answer 27

Extradural - rapid - trauma
Subdural - slow - trauma
Subarachnoid - ruptured aneurysms
Intracerebral - spontaneous rupture of vessels

Question 28

What is the difference between the dura on the vertebral column compared to the brain?

Answer 28

dura in vertebral column has 1 layer whereas dura in skull as 2

Question 29

What are the two layers of dura in the skull called?

Answer 29

Periosteal and meningeal

Question 30

What is the name given to the fold of dura that extends between the medial surfaces of the two hemispheres?

Answer 30

Falx cerebri

Question 31

Why are extradural haemorrhages more rapid onset than subdural haemorrhages?

Answer 31

extradural are caused by rupture of a meningeal artery which is more high pressure

subdural = meningeal vein - low pressure