Download neuroanatomy 10 [4-20

Chapter 10
Vascular Supplies
1.
What part of the brain is most important for attention to [usually] the left body?
 Association cortex in the right parietal lobe (usually nondominant right side, fed by Inferior
Right MCA, and superior branch to a lesser extent)
2.
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What are the major arterial branches of the supraclinoid internal carotid artery?
OPAAM: Opthalmic, Posterior communicating, Anterior choroidal, Anterior cerebral, Middle
cerebral
3.
What artery supplies the medial sensorimotor cortex? What supplies the lateral frontal lobe?
 Anterior cerebral artery
 Middle cerebral artery
4.
What are the two main divisions of the ACA? MCA?
 Callosomarginal a. (superior) and pericallosal a. (inferior)
 MCA Superior and inferior divisions
5.
What arteries coming from the MCA perforate into the brain? Where do they go? How are they
vulnerable?
 Lenticulostriate arteries
 To basal ganglia (particularly caudate nucleus) and middle internal capsule
 Vulnerable to lacunar (small-vessel) infarction=> contralateral hemiparesis, hemiballismus
6.
What does the anterior chorodial artery supply in its role as another deep perforant artery (4)?
What happens when an infarction occurs here?
 Globus pallidus, putamen, thalamus, and posterior internal capusle
i. Branches directly off of carotid
 Also vulnerable to lacunar infarctions => contralateral hemiparesis
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8.
Which arteries are really similar and come off of the ACA? PCA?
The recurrent artery of Heubner comes off the ACA
Thalamogeniculate & thalamoperforator aa. come off the PCA
So, ACA=> anterior limb of internal capsule; MCA=> middle (genu) internal capsule;
anterior chorodial=> posterior internal capsule
Which way do the eyes point after an MCA stem infarction?
 Towards the side of the lesion; due to damage of cortical areas that drive the eye
contralaterally
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What part of the body do ACA infarcts affect? What are some other problems that can occur?
Contralateral leg weakness and sensory loss; larger lesions cause hemiplegia
Nondominant strokes can cause contralateral neglect (see #1); alien hand syndrome, apraxia,
abulia, flat affect, incontinence, and impaired judgement
10. How can a PCA infarct mimic an MCA infarct (2)?
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If a dominant side (usually left sided) infarction of the thalamogeniculate arteries occur=>
contralateral sensory loss, contralateral motor loss, thalamic aphasia
MCA stem infarct can cause homonymous hemianopia
11. How do watershed infarcts happen? What are the results (ACA-MCA, MCA-PCA)?
 Sudden drop in BP in a patient with carotid stenosis, or carotid occlusion
 “man in the barrel:” trunk and proximal arm & leg weakness
i. in the dominant hemisphere: transcortical aphasia
 MCA-PCA: disruption of higher order visual processing
12. What is a weird cause of transient neurologic episodes in the elderly?
 hypoglycemia
13. When do proteinaceous infarcts occur?
 Marantic endocarditis (non-bacterial thrombotic endocarditis)
14. When are lacunes usually seen? What are the results of (1) thalamic and (2) basal ganglia
lacunes?
 Chonic hypertension=> lipohyalinosis => lacunar infarcts
 Contralateral sensory deficits
 Asymptomatic or Hemiballinismus (involuntary rotatory movements, one sided or one limb)
15. What causes ataxic hemiparesis? What is it?
 Damage to propioceptive or cerebellar circuitry, not cerebellum itself like in plain ataxia
 Like pure motor hemiparesis (and same causes), but with ipsilateral ataxia
16. What is the standard procedure for a patient with a stroke?
 CT to rule out hemorrhage
 If negative, and if onset was less than 4.5 hours ago=> administer tPA
 If you can’t give tPA, administer aspirin
17. How can you treat extreme edema from an MCA infarct?
 hemicraniectomy
18. What are the symptoms of (1) carotid dissection and (2) vertebral dissection?
 Turbulent sound with each heartbeat and ipsilateral Horner’s syndrome and eye pain
 Posterior neck and occipital pain
19. Where does the inferior anastomotic vein of Labbe drain? The superior anastomotic vein of
Trolard? Superficial middle cerebral vein? Anterior cerebral and deep middle cerebral veins?
 Transverse sinus
 Superior saggital sinus
 Cavernous sinus – drains anteriorly
 basal veins of Rosenthal=> great vein of Galen
20. When is saggital sinus thrombosis more likely to occur? What are the radiologic signs?
 Hypercoagulable states, pregnancy and a few weeks postpartum
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Empty delta sign; increased CT density, increased T1 signal of the whole sinus
i. Big non-radio sign is intracranial pressure
1 Cavernous portion of internal carotid artery (carotid siphon)
2 Anterior cerebral artery
3 Middle cerebral artery
4 Cervical portion of internal carotid artery