Anatomical Basis of Stroke

Question 1

The basilar artery bifurcates to give rise to ..

Where does this occur?

Answer 1

posterior cerebral artery

interpeduncluar fossa, just caudal to the mammillary bodies

Question 2

The base of the posterior cerebral arteries give rise to…

which course along the lateral margin of the interpeduncular fossa (lateral to mammillary bodies) to anastomose with what?

Answer 2

posterior communicating artery

internal carotid artery

Question 3

The rostral surface of the internal carotid artery gives rise to… that courses over…

Answer 3

anterior cerebral artery

the superior surface of the optic nerve

Question 4

After giving rise to the anterior cerebral artery, the internal carotid continues superiorly as the …

Answer 4

middle cerebral artery

Question 5

The paired anterior cerebral arteries are connected by a small…

typically near the level of the caudal end of …

Answer 5

anterior communicating artery

the olfactory tract

Question 6

What is the arterial ring around the ventral surface of the brain at the level of the hypothalamus called?

Answer 6

Circle of Willis

Question 7

Each half of the ring consists of (from caudal to rostral):

Answer 7

• posterior cerebral artery
• posterior communicating artery
• internal carotid artery
• anterior cerebral artery
• anterior communicating artery

Question 8

The Circle of Willis is primarily supplied by what artery?

Answer 8

Internal carotid artery

Question 9

What is the most important branch coming off of the Circle of Willis?

Answer 9

middle cerebral artery

Question 10

The anterior cerebral artery, after passing over the superior surface of the optic nerve, enters the inferior aspect of the… to course along the surface of the ….

This artery follows an arching course caudally, remaining close to the superior surface of…

Answer 10

Longitudinal Cerebral Fissure

Cerebral Hemisphere

Corpus Callosum

Question 11

What does the anterior cerebral artery perfuse?

Answer 11

• medial surface of the frontal and parietal lobes
• medial portion of the inferior (orbital) surface of the frontal lobe
• superolateral surfaces of the frontal and parietal lobe (less than 1 inch in breadth)
• perforating branches get the corpus callosum except for the caudal end (splenium)

Question 12

The Cingulate Sulcus gives rise to two dorsally directed branches; one branch occurs over the body of the corpus callosum, typically remaining on the medial surface of the brain. What is the other branch called, and what direction does it go?

Answer 12

Marginal Sulcus

forms the caudal end of the cingulate sulcus and extends onto the superolateral surface of the brain

Question 13

Immediately rostral to the marginal sulcus is a relatively small U shaped gyrus called…

Why is this an important landmark?

Answer 13

Paracentral gyrus

• caudal limb of the gyrus is the medial continuation of the somatosensory cortex (parietal lobe)
• while the rostral limb is the medial continuation of the primary motor cortex (frontal lobe)

Question 14

How does the Central Sulcus anatomically relate to the Paracentral Gyrus?

Answer 14

it rests between the tips of the paracentral gyrus on the superior surface of the brain, but does not continue onto the medial surface

Question 15

All of the medial surface of the brain superior to the cingulate sulcus and rostral to the paracentral gyrus is the …

Answer 15

superior frontal gyrus

Question 16

The medial surface of the parietal lobe is represented primarily by a large rectangular field the …

What are its borders?

Answer 16

precuneus

• bordered rostrally by marginal sulcus
• caudally by parieto-occipital sulcus
• inferiorly by cingulate sulcus

Question 17

What horizontal sulcus is present on the medial surface of the occipital lobe?

Answer 17

calcarine sulcus

Question 18

The lobe dorsal to the calcarine sulcus is the … while the lobe ventral to the calcarine sulcus is the…

Answer 18

cuneus

lingual gyrus

Question 19

What are common manifestations of CVAs involving the anterior cerebral artery?

Answer 19

• paralysis and sensory disruption in foot/leg
• urinary incontinence
• gait apraxia
• transcortical motor aphasia
• cognitive impairment
• ideomotor apraxia

Question 20

What higher-order control centers are located in the paracentral gyrus? What artery supplies this area?

Answer 20

micturition and defecation

anterior cerebral artery

Question 21

The superior frontal gyrus contains the supplementary motor cortex that is generally in charge of what that could be affected by an anterior cerebral artery stroke?

Answer 21

“normal” gait

Question 22

What is transcortical motor aphasia? Where would there be injury in the brain that could cause this symptom?

Answer 22

difficulty with spontaneous vocalization

antero-superior portion of frontal lobe

Question 23

Ideomotor apraxia, the inability to perform simple hand gestures, particularly with tool use is a manifestation of damage to what?

Answer 23

corpus callosum

Question 24

What does the posterior cerebral artery perfuse off of its main branches?

Answer 24

• inferior surface of temporal lobe except for the rostral tip (temporal pole)
  
  • far enough laterally to cover a strip on the inferolateral surface of the temporal lobe
• inferior to medial surface of occipital lobe
  
  • all of the medial surface of occipital lobe
  • lateral surface of occipital pole

Question 25

What does the posterior cerebral artery course over? As it goes over this, what branches does it give rise to?

Answer 25

cerebral peduncle perforating branches - thalamic branches

Question 26

What do thalamic branches of the posterior cerebral artery perfuse?

Answer 26

* crus cerebri * substantia nigra * caudal portion of the thalamus

Question 27

The portion of the frontal lobe medial to the olfactory sulcus is called what? The portion lateral to the olfactory sulcus is called what?

Answer 27

gyrus rectus orbital gyrus

Question 28

The uncus sits at the same level as what other prominent feature?

Answer 28

mammillary bodies

Question 29

The uncus is part of what gyrus?

Answer 29

parahippocampal gyrus

Question 30

What sulcus is medial to the parahippocampal gyrus? What sulci are lateral to the parahippocampal gyrus?

Answer 30

parahippocampal sulcus Rhinal sulcus (rostrally) Collateral sulcus (caudally)

Question 31

What is between the inferior temporal sulcus (laterally) and the collateral and rhinal sulci (medially) on the inferior surface of the temporal and occipital lobes?

Answer 31

occipitotemporal gyri

Question 32

What forms the inferomedial surface of the occipital lobe?

Answer 32

lingual gyrus

Question 33

What will be clinical deficits of a posterior cerebral artery CVA?

Answer 33

* blindness or other visual defects * memory deficiencies * partial or total anosmia

Question 34

The primary visual cortex and the visual association cortex are perfused by what vessel?

Answer 34

posterior cerebral artery

Question 35

Why would you get memory deficiencies with a posterior cerebral artery CVA?

Answer 35

perfusion of the parahippocampal gyrus and the underlying hippocampus would be stunted

Question 36

Anosmia is seen with CVA to posterior cerebral artery because it disrupts the olfactory cortex which is found where?

Answer 36

area around the rhinal sulcus, the underlying amygdala

Question 37

The middle cerebral artery originates from the internal carotid and courses...

Answer 37

laterally in the rostral end of the lateral sulcus

Question 38

The initial part of the middle cerebral artery gives rise to multiple perforating branches named... What do they perfuse?

Answer 38

Striate Arteries * basal ganglia, * red nucleus, * majority of the internal capsule * posterior crus and genu

Question 39

The striate artery that originates most proximally off of the middle cerebral artery is called...

Answer 39

Artery of Cerebral Rupture

Question 40

Besides giving off striate arteries, the middle cerebral artery also gives off branches to perfuse what other areas?

Answer 40

inferolateral surface of occipital lobe temporal pole

Question 41

The middle cerebral artery reaches the lateral surface of the brain and deflects caudally along the lateral fissure. During this part of its route, what does it perfuse?

Answer 41

majority of teh lateral surfaces of the frontal, parietal, occipital, and temporal lobes of the brain

Question 42

What sulcus courses roughly horizontally across most of the parietal lobe, beginning just caudal to the postcentral sulcus? What two lobules does it create?

Answer 42

intraparietal sulcus creates superior and inferior parietal lobules

Question 43

What two sulci are within the inferior parietal lobule?

Answer 43

caudal end of the lateral fissure caudo inferiorly the caudal end of teh superior temporal sulcus

Question 44

What is the area around the caudal end of the lateral sulcus called?

Answer 44

supramarginal gyrus

Question 45

What is the area surrounding the caudal end of the superior temporal sulcus called?

Answer 45

angular gyrus

Question 46

How is the lateral surface of the occipital lobe divided?

Answer 46

into superior and inferior occipital gyri

Question 47

What are common deficits seen with a middle cerebral artery CVA?

Answer 47

* paralysis and hyperesthesia in face and arm * breakdown of conjugate gaze * "global" aphasia

Question 48

To cause damage of sensory and motor function, what was the middle cerebral artery perfusing?

Answer 48

lateral portion of the premotor cortex striate arteries got internal capsule with corticobulbar and corticospinal tracts and somatosensory radiation from the thalamus

Question 49

How does a middle cerebral artery CVA damage conjugate gaze?

Answer 49

both frontal eye fields and parietal eye fields are perfused by the middle cerebral artery

Question 50

What is damaged when the middle cerebral artery has a CVA and the pt now has aphasia?

Answer 50

Broca's (inferolateral frontal lobe) and Wernicke's area (between superior temporal gyrus and the angular gyrus)

Question 51

The middle cerebral artery does not perfuse...

Answer 51

peripheral margin of any of the lobes of the brain

Question 52

The posterior cerebral artery does not perfuse.. What artery does?

Answer 52

the temporal pole middle cerebral artery

Question 53

The middle cerebral artery does not perfuse the inferomedial portion of...

Answer 53

the frontal lobe