1. Blood supply to the brain.pdf

Question 1

Unconsciousness cessation of cerebral circulation with _______

Answer 1

15 seconds

Question 2

At body temperate nerve cell damage/death starts in ______

Answer 2

Three minutes

Question 3

What are the 4 main arteries that supply the brain?

Answer 3

R and L internal carotid arteries (ant)

R and L vertebral arteries (post)

Question 4

What is the pathways of the vertebral artery and it’s branches?

Answer 4

• Branch of the first part of the subclavian artery*
• -> Ascends in the neck through the foramina in the transverse processes (upper six cervical vertebrae)
• ->Enters the skull via foramen magnum and pierces the meninges to enter the subarachnoid space
• ->At the lower border of the ventral pons it joins the vessel on the opposite side to form the basilar artery.

Question 5

What is the basilar artery?

Answer 5

The artery formed by the union of the vertebral arteries.
Then ascends on the ANTERIOR surface of the pons
Terminates by dividing into two POSTERIOR CEREBRAL ARTERIES

Question 6

Branches of the vertebral and basilar artery?

Answer 6

[Sup]
Posterior cerebral artery
Superior cerebellar artery
Pontine arteries
Labyrinthine artery
Anterior inferior cerebellar artery (AICA)
Posterior inferior cerebellar artery (PICA)
Anterior spinal artery 
[Inf}

Note: The posterior spinal artery is a brain of the vertebral or posterior inferior cerebellar artery

Question 7

Which 3 main blood vessels supply the cerebellum?

Answer 7

SCA: Superior cerebellar artery
AICA: Anterior inferior cerebellar artery
PICA: Posterior inferior cerebellar artery

Question 8

Pathway of the internal carotid artery?

Answer 8

Begins at the bifurcation of the common carotid artery
Ascends in the neck, then passes into the skull through carotid canal in the temporal bone
Passes through the cavernous sinus
Perforates the dura mater at the anterior clinoid process and enters the subarachnoid space
Divides into ANTERIOR and MIDDLE CEREBRAL arteries

Question 9

What is the Bouthillier classification of the carotid artery radiologically?

Answer 9

C1: Cervical segment
C2: Petrous segment (carotid canal)
C3: Lacerum segment (above not in the foramen)
C4: Cavernous segment (cavernous sinus)
C5: Clinoid segment (clinoid process – pierces dura)
C6: Ophthalmic segment (opthalmic artery origin)
C7: Communicating segment (posterior communicating a. origin)

Question 10

What are the branches of the cerebral portion of the internal carotid artery?

Answer 10

Ant. communicating artery
Post. communicating artery
Ant. choroidal artery
Ant. cerebral arteries 
Middle cerebral arteries

Question 11

What are the close relations to the circle of willis (circulus arteriosus)?

Answer 11

Cerebral peduncles
Optic chiasma
Pituitary stalk
Oculomotor nerves

Question 12

Which artery passes through the lateral fissure?

Answer 12

Middle cerebral artery passes laterally through the lateral fissure and emerges onto the lateral surface of the cerebral hemisphere

Question 13

Symptoms of a stroke in the middle cerebral artery (MCA)?

Answer 13

Contralateral hemiplegia (paralysis)
Hemi-sensory loss (blindness over half of the visual field)
Contralateral hemianopia (visual pathway)
\+/- dysphasia (dominant hemisphere)
\+/- anosognosia (neglect/impaired perception defects, non dominant hemisphere)

Question 14

Anterior cerebral artery lesion effects…

Answer 14

seen in opposite foot and leg

Question 15

Symptoms of stroke in anterior cerebral artery?

Answer 15

1. Weak contralateral leg and possibly arm
2. Sensory loss in contralateral foot and leg
3. Gait apraxia (difficulty initiating walking movement) 4. Akinetic mutism (paucity of movement and speech)
4. Urinary incontinence

Question 16

Symptoms of stroke in posterior cerebral artery?

Answer 16

Contralateral Homonymous hemianopia +/- macula sparing

Hemianopia = blind over half of visual field

Question 17

Most common variants in the circle of willis?

Answer 17

1. Shunt across the two Ant communicating arteries (ACA)
2. Right anterior and posterior hypoplasia
3. Left anterior and posterior hypoplasia

Question 18

What arteries supply the basal ganglia and internal capsule?

Answer 18

Medial striate branches of ACA (ant com)
Lateral striate branches of MCA (middle cerebral)
Anterior choroidal

Question 19

What arteries supply the thalamus>

Answer 19

Branches of PCA

Question 20

What arteries supply the midbrain?

Answer 20

From PCA

Question 21

What arteries supply the pons?

Answer 21

Basilar
SCA (sup cerebral)
AICA (anterior inferior cerebral artery)

Question 22

What arteries supply the medulla?

Answer 22

Verebral
Anterior spinal
Inferior cerebellar
Basiliar
Posterior spinal

Question 23

Blood supply to brainstem (for posterior circulation)?

Answer 23

Midbrain: Posterior cerebral (circumference and centrally)
Mid pons: AICA, basilar
Rostral medulla: PICA, vertebral artery, Anterior spinal
Caudal medulla: Posterior spinal, vertebral, PICA, anterior spinal

Question 24

Which cranial nerves are found at the 3 areas of the brainstem?

Answer 24

Midbrain: 3,4
Pons: 5,6,7,8
Medulla: 9,10,11,12