Path of Cerebrovascular Disease & Stroke (Bambach & Pieper)

Question 1

these two neuron populations are especially vulnerable to global ischemia/hypoxia

Answer 1

hippocampus neurons and Purkinje neurons in the cerebellum

Question 2

this is the most common disease process responsible for thrombosis or embolism

Answer 2

atherosclerosis

Question 3

what structural damage would you expect from a partial thrombus of the MCA, involving primarily the lenticulstriate branches?

Answer 3

infarct confined to the basal ganglia/thalamic nuclei

Question 4

what is the disease process behind the picture shown below?

Answer 4

this is a cholesterol embolus - you can tell because of the spicule-like clear spaces, which represent cholesterol clefts that were left behind during the lipid extraction/processesing of this sample; so we know this is from an atherosclerotic plaque

Question 5

this type of infarct in the brain is usually due to thrombus and results in no reperfusion of the ischemic tissue

Answer 5

non-hemorrhagic

Question 6

this type of infarct in the brain is usually due to an embolus and results in reperfusion of all or part of the ischemic tissue

Answer 6

hemorrhagic

Question 7

All of the following are changes associated with acute stage infarct EXCEPT:

A. Coagulation necrosis

B. Axonal degeneration

C. Cerebral edema

D. Vascular proliferation

E. Reactive gliosis

F. Neutrophil response

Answer 7

E. This is a change associated with the subacute stage (~1-4 weeks after initial insult)

Question 8

these two changes dominate the subacute stage of infarct

Answer 8

marcophages & reactive gliosis (gemistocytes)

Question 9

cyst formation and glial scarring characterize the ____ stage of tissue infarct, occuring ~5 weeks after the initial insult

Answer 9

remote

Question 10

why is white matter in the infant brain especially susceptible to asphyxia?

Answer 10

because oligodendrocytes are busy myelinating axons, which increases their metabolic activity making them more vulnerable to anoxic injury

*their neurons, on the other hand, are relatively resistant to anoxic-hypoxic injury

Question 11

this can be thought of as a meltdown of whte matter adjacent to the ventricles in term infants that have undergone asphyxia:

Answer 11

periventricular leukomalacia

Question 12

where do most hypertensive hemorrhages arise in the brain?

Answer 12

basal ganglia/thalamus (2/3)

*the rest arise in the pons and cerebellum

Question 13

these aneurysms typically arise at branch points in or near the major arteries that form the Circle of Willis, and when they rupture, bleeding is usually confined within the subarachnoid space at the base of the brain

Answer 13

saccular (berry) aneurysms

Question 14

most saccular aneurysms arise in the _____ circulation, with the majority arising at the branch point between the ______ and the _______.

Answer 14

anterior circulation; most arise between the ACA and the anterior communicating artery

Question 15

what vascular malformation is shown below that may result in stroke-like episodes due to local ischemia of surrounding tissue as the result of a ‘steal’ phenomenon?

Answer 15

arteriovenous malformation (AVM)

Question 16

this type of hemorrhage involves primarily the white matter, sparing of the adjacent deep gray structures (in contast to spontaneous hypertensive hemorrhages)

Answer 16

lobar intraparenchymal hemorrhage (of amyloid angiopathy)

Question 17

Which is more common: ischemic or hemorrhagic stroke?

Answer 17

ischemic; with arterial occlusion more common than venous.

Question 18

Which of the following statements about stroke is TRUE?

A. Most of the time, ischemic stroke is due to a venous occlusion

B. Symptoms of stroke correlate to a specific lobe

C. Ischemic stroke does not include cases of global ischemia

D. Though the presenation of stroke differs by case, the mechanism is always the same

E. The rapidness of loss of function during stroke depends on how much energy is stored in that particular brain

Answer 18

C. Global ischemia is caused by something more like cardiac arrest.

A - ischemic stroke is usually due to an arterial occlusion

B - symptoms correlate to the vascular territory, not exclusively to a single lobe

D - there are multiple mechanisms of stroke (ie occlusion, hemorrhage, compression, etc)

E - the brain does not maintain energy reserves - there is no energy storage

Question 19

cerebral metabolism depends on aerobic or anaerobic metabolism?

Answer 19

aerobic; astrocytes use glucose for glycolysis to make lactate, which is taken up and oxidized by the mitochondria in the neurons to make fuel for oxidative phosphorylation

Question 20

All of the following are metabolic consequences of ischemia, leading to loss of control of electrolyte gradients and cell death, EXCEPT:

A. Cellular influx of Ca++ and K+, efflux of Na+

B. Increased intracellular water

C. Release of free radicals that activate apoptotic genes

D. Increased activity of phospholipases, proteases, and endonucleases

E. Depolarized external membrane

Answer 20

A. There is an influx of Na+ in and efflux of K+ out of the cell.

Question 21

type of stroke that affects the large vessles

Answer 21

atherothrombotic (25% of all strokes)

Question 22

type of stroke that affects the small vessels

Answer 22

lacunar (25% of all strokes)

Question 23

type of stroke arising from afib or structural heart disease

Answer 23

cardioembolism (25% of all strokes)

Question 24

a stroke of this large vessel will present with behavior change and leg weakness

Answer 24

ACA

Question 25

A stroke of this large vessel will present with lack of awareness of the problem (anosognosia), left neglect, left sided weakness, right gaze deviation (injury to the right frontal eye field) and quadrant/or hemianopsia

Answer 25

Right MCA

Question 26

A stroke of this large vessel in a right-handed patient will present with aphasia, right sided weakness, left gaze deviation, quadrant/or hemianopsia

Answer 26

left MCA

Question 27

in _____ artery occlusion, the reticular formation is involved and thus the patient will present with coma

Answer 27

basilar

Question 28

occlusions of this artery will not produce “cortical” signs as there is typically redundant flow from its contralateral counterpart to the rest of the posterior circulation - will instead see incoordination, vertigo, nystagmus, Wallenberg or locked in syndrome

Answer 28

vertebral

• wallenberg= lateral medulla stroke
• locked-in syndrome = medial medulla stroke
• unilateral uncoordination = PICA stroke

Question 29

A stroke in this large vessel will present with hemi-visual field loss (homonymous hemianopsia)

Answer 29

PCA

Question 30

classic lacunar stroke, presents with no cortical signs or symptoms, instead:

• ipsi facial numbness, incoordination, Horner’s
• contra body numbness
• hiccups, hoarseness, dysphagia
  
  • vertigo and nystagmus

Answer 30

wallenberg syndrome (lateral medullary syndrome)

Question 31

All of the following are hallmark features of small vessel strokes (lacunar syndromes) EXCEPT:
A. Pure motor weakness

B. Pure sensory loss

C. Diplopia

D. Disturbance of consciousness

E. Vertigo

Answer 31

D. Unlike the “large vessel” stroke of the basilar artery, the lacunar stroke involving the small vessels off the basilar will not be sufficient to injure the reticular formation

Question 32

______ and ______ are acute onset “stroke mimics” that should be considered when determining the cause of injury

Answer 32

hypoglycemia and seizure

*migraine is also a possibility but should only be considered after other causes are ruled out - it is a diagnosis of exclusion

Question 33

treatment of emoblic stroke, though may be sensitive as early treatment may worsen intraparenchymal bleeding after ischemic stroke (hemorrhage transformation)

Answer 33

anticoagulation therapy

Question 34

most common cause of intraparenchymal hemorrhage

Answer 34

hypertension, leading to breakage of the perforator arteries

*may also be caused by tumor, drugs, infection, vessel malformations, and coagulopathies

Question 35

All of the following are common locations for hypertensive hemorrhage EXCEPT:

A. Putamen

B. Caudate

C. Thalamus

D. Pons

E. Cerebellum

Answer 35

B. Only on the rare occasion will the Caudate be involved.

Question 36

True or False: Rapid and strict control of blood pressure is the best treatment for a hypertensive brain bleed.

Answer 36

False. A hemorrhage will continue to grow despite efforts to control blood pressure. Initial treatment of hemorrhagic stroke includes an aneurysm clip if it is in the subarachnoid, an intraventricular drain if there is hydrocephalus, and blood pressure control for intraparechymal bloeeding. Mostly supportive care is needed, as after 24 hours the bleeding will tamponade against the surrounding tissue and eventually clear.

Question 37

headache, nausea/vomiting, pinpoint pupils, and coma all point to a hemorrhagic stroke where?

Answer 37

pons

Question 38

headache, nause/vomiting, vertigo and coma all point to a hemorrhagic stroke where?

Answer 38

cerebellum

*cerebellar and pontine hemorrhages occur in the posterior fossa, so of particular concern is herniation and increased ICP. If the reticular formation becomes injured, this is a neruologic emergency and typically requires airway and ICP control, perhaps ventricular drainage placement.

Question 39

secondary periclot neuronal injury in the form of edema ~24-48 hours after hemorrhagic stroke is though to occur via what mechanism?

Answer 39

breakdown of BBB and accompanying inflammatory response to breakdown products

Question 40

67 yo right-handed man has sudden right sided weakness while driving. When found by paramedics, he cannot produce words, but seems to comprehend what is spoken to him. He has left gaze deviation, right homonymous hemianopsia and right hemiparesis. BP is 180/90 and HR is irreg irreg in the 100s. Where, what, and why is this lesion?

Answer 40

Where: Left hemisphere - L gaze deviation, aphasia, right visual field loss, right hemiparesis

What: Ischemic stroke, embolus, left MCA

Why: A fib -irreg irreg HR

Question 41

74 yo Caucasian man found at home by family at 6 pm. He was last seen normal that morning. He is noted to have left sided weakness and is looking to the right. He does not think there is anything wrong with him. He is a diabetic and a smoker. BP 145/78, HR 85 and regular. He cannot recognize his left hand, he thinks its yours. He does not bleieve that there is anything wrong with him. He has left gaze deviation and left VF loss, as well as left hemiparesis. Where, what and why is this lesion?

Answer 41

Where: right hemisphere

What: ischemic stroke, right MCA

Why: large vessel athersclerosis (smoking, DM, ethnicity) or possibly occlusion

Question 42

A 55 yo man was at work when he was suddenly witnessed by his coworkers to wince and grip his head. He then collapsed. Paramedics on the scene note pinpoint pupils and poor respiration. He was immediately intubated and taken to the closest medical facility. Familly members share that he has a history of hypertension and recently stopped his meds. BP is 260/135, HR 45, comatose. Where, what and why is this lesion?

Answer 42

Where: pons - coma with pinpoint pupils

What: hemorrhage - headache, hypertension, sudden onset

Why: hypertensive hemorrhage

Question 43

Which of the following is NOT part of the acute therapy for ischemic stroke?

A. ivTPA window is 4.5 hours for all patients

B. the goal for ivTPA is 45 minutes “door to needle”

C. For patients who have a defined clot in the larger cerebral vessels, a paired treatment with intra-arterial approach may be offered.

D. After emergent stabilization and treatment with tpa, the patient should be admitted to a primary stroke or comprehensive stroke center.

Answer 43

A. Currently this is only for patients under 80. It is otherwise thought to be too risky for bleeding.