Blood Supply

Question 1

why is blood supply so important

Answer 1

1. CVD and CVA - constitute the most common cause of neurological deficits
2. TIAs (total ischemic attacks) - sudden drop of systemic BP
3. Hemorrhagic vs. Thrombolytic strokes
4. Aneurysms

Question 2

Internal Carotid Artery

Answer 2

anterior circulation –> 80% blood supply to cortex

Question 3

Branches internal carotid artery

Answer 3

Anterior cerebral artery
Middle cerebral artery
Posterior communicating artery
Watershed zones

Question 4

Anterior Cerebral Artery

Answer 4

Runs in longitudinal fissure
Supplies medial aspect of the frontal and parietal lobes and medial sensorimotor cortex
Anterior communicating artery (btw the two anterior cerebral arteries)

Question 5

Middle Cerebral Artery

Answer 5

Supplies virtually entire lateral surface of cerebral hemispheres
Specialized Branches –> Lateral Striate going to basal nuclei and internal capsule (stroke central)
Superior and Inferior divisions

Question 6

Middle Cerebral A. Superior Division

Answer 6

Cortex above lateral fissure

Supplies lateral frontal cortex including precentral and postcentral gyri

Question 7

Middle Cerebral A. Inferior Division

Answer 7

cortex below lateral fissure

supplies lateral temporal lobe, parts of the parietal lobe

Question 8

Posterior communicating artery

Answer 8

?

Question 9

Watershed Zones

Answer 9

Regions of the cortex between two cerebral vessels
Infarcts in the areas can occur with severe drops in systemic blood pressure
Interphases btw two major blood supplies

Question 10

Vertebral - Basilar System

Answer 10

Posterior circulation, 20% blood supply to cortex

Question 11

Branches from vertebral

Answer 11

Posterior spinal arteries
Anterior spinal artery
Posterior inferior cerebellar artery

Question 12

Branches from Basilar

Answer 12

Anterior inferior cerebellar artery
Superior cerebellar artery
Pontine arteries
Posterior cerebral artery

Question 13

Posterior Spinal Arteries

Answer 13

Off vertebral
Run caudaully on dorsolateral sulci of spinal cord
Reinforced b arteries (parietal brs) as the descend

Question 14

Anterior Spinal Artery

Answer 14

Off vertebral
Joins its mate from opp side forming one single artery
Runs in anterior median fissure - along the ventral midline of the spinal cord
Paramedian branches supply medial caudal medulla
Reinforced by arteries (parietal brs.) as it descends

Question 15

Posterior Inferior Cerebellar Arteries

Answer 15

Off vertebral

Supplies inferior surface of the cerebellum, choroid plexus, lateral medulla

Question 16

Anterior Inferior Cerebellar Arteries

Answer 16

off basilar

Supplies the anterior, inferior surface of the cerebellum and caudal lateral pons

Question 17

Superior Cerebellar Arteries

Answer 17

off basilar

Supply superior surface of the cerebellum, caudal midbrain (tectum) and rostral pons

Question 18

Pontine Arteries

Answer 18

off basilar
paramedian branches supply medial pons
circumferential branches supply lateral pons

Question 19

Terminal of Vertebral-Basilar System

Answer 19

Superior Cerebellar Arteries

Posterior Cerebral Arteries

Question 20

Posterior Cerebral Arteries

Answer 20

Arise from bifurcation of basilar at level of midbrain
Supplied midbrain, most of thalamus, medial and inferior surfaces of the occipital and temporal lobes including hippocampus

Question 21

Branches from posterior cerebral arteries

Answer 21

Parietooccipital branch and Calcarine branch (visual cortex)

Also thalamoperfortor, thalamogeniculate, and posterior choroidal arteries

Question 22

Posterior Cerebral anastomasoses with

Answer 22

ant cerebral

Question 23

Circle of Willis

Answer 23

the communication of anterior and posterior circulations to the cerebrum and brainstem
(not a true anastomotic circle)

Question 24

Circle of Willis - Wada test

Answer 24

Cannulate the internal carotid artery and infuse barbituates to put the cortex to sleep. Patient will read passage until unconscious. depending on speech before unconscious state will determine dominant hemisphere - primarily done with left handed people

Question 25

Circle of Willis - Communicating arteries

Answer 25

Anterior = joins anterior cerebral arteries
Posterior = joins internal carotid arteries with the posterior cerebral arteries

Question 26

Great Cerebral Vein of Galen

Answer 26

Main Brain Drain Vein

Lies midline behind the midbrain btw the cerebrum and cerebellum

Question 27

Basal veins of rosenthal

Answer 27

Receives venous blood from the deep cerebral veins, names are the same as the cerebral arteries (anterior, dee middle, posterior)

Question 28

Superior anastomotic vein of Trolard

Answer 28

Receives blood from the superficial middle cerebral vein

Drains superficial venous blood into superior sagittal sinus

Question 29

Inferior anastamotic vein of Labbe

Answer 29

Receives blood from the superficial middle cerebral vein

Drains superficial venous blood into the confluence of sinuses posteriorly

Question 30

Bridging veins

Answer 30

veins that drain venous blood from the surface of the brain penetrate the arachnoid mater then the dura mater to enter the dural venous sinuses