Lec 59 Cerebrovascular Disease

Question 1

What are focal pathologies of CV disease?

Answer 1

disease of blood vessels

- arteriosclerosis, HTN, DM, aneurysm, vasculitis

Question 2

What are global pathologies of CV disease?

Answer 2

alterations in blood flow or quality of blood supply

- hypoperfusion, hypoxia, hypoglycemia

Question 3

What is a cerebral infarct?

Answer 3

prolonged ischemia to vascular territory causing tissue necrosis

Question 4

What are some etiologies of cerebral infarct aka stroke]?

Answer 4

• thromboembolus = most common cause, from carotid artery
• thrombosis over local plaque = posterior circ
• atherosclerosis in circle of willis = posterior circ
• focal high grade stenosis
• arterial spasm

Question 5

Where does thrombo-embolus causing cerebral infarct usually originate from?

Answer 5

carotid artery

often hemorrhagic

Question 6

Where does thrombosis causing cerebral infarct usually originate from?

Answer 6

posterior circulationg

Question 7

What generally happens in acute infarct?

Answer 7

• edema swelling, pallor, sometimes hemorrhagic
• activation of PMNs
• can lead to herniation if untreated –> secondary infarction by compression of more arteries

Question 8

What generally happens in a subacute infarct?

Answer 8

• around 3-5 days post-infarct
• swelling decreases, infiltration of macrophages = lipid laden macrophages
• vascular proliferation at edges of infarct
• clot contraction –> can lead re-perfusion of necrotic area and hemorrhagic infarct

Question 9

What generally happens in chronic/remote infarct?

Answer 9

characterized by cystic cavity in area where neurons once were
secondary wallerian [anterograde] degeneration of damaged axons distal to site of neuronal damage

Question 10

What are signs of uncal compression of 3rd nerve?

Answer 10

unilateral blown pupil

Question 11

What are duret hemorrhages?

Answer 11

• small areas of bleeding in upper brainstem due to herniation causes pressure on midline rostral brainstem and putting traction on blood vessels that penetrate brain stem
• usually fatal outcome

Question 12

What is subpial sparing?

Answer 12

zone of residual brain parenchyma underneath pia

sign of of infarct [distinguish from old traumatic injury]

Question 13

What are potential causes of cerebral and meningeal hemmorhage?

Answer 13

• trauma
• vascular malformation: berry anuerysm
• blood dyscrasia [clotting problem]
• HTN: turbulent flow causes changes in cerebral small vessels that predispose to bleeding; mostly in gray matter in cerebral hem
• cerebral amyloid angiopathy –> causes lobar hemorrhage

Question 14

What is cerebral amyloid angiopathy?

Answer 14

amyloid deposition in cortical and leptomeningeal arterioles

causes lobar hemorrhage

Question 15

What are charcot-bouchard aneurysms?

Answer 15

in small vessels [usually lenticulostriate] at basal ganglia
if rupture –> intracerebral hemorrhage and may lead to hemorrhagic stroke

associated with chronic HTN

Question 16

What is vacular lipohylainosis?

Answer 16

small vessel wall thickening in brain = smaller lumen, can lead to cerebral hemorrhage

Question 17

What is outcome of hemorrhage? how does this differ from infarction?

Answer 17

if uncomplicated by rupture into ventricular system = can resolve into slit-like cavities, and cause limited parenchymal damage

infarction = parenchymal damage not able to be restored

Question 18

What is berry/saccular aneurysm?

Answer 18

aneurysm of circle of willis
causes subarachnoid hemorrhage or hemorrhagic stroke
present with worst headache of one’s life

Question 19

What are some causes of global brain hypoxia?

Answer 19

stagnant: ischemic and oligemic = reduced or no flow

anoxic and hypoxic = reduced or no oxygen

anemia = decreased carrying capacity

histotoxic = poison, CO

hypoglycemic

Question 20

What is effect of global brain damage?

Answer 20

diffuse swelling and edema –> death if swelling not managed

Question 21

What are areas of selective vulnerability to hypoxia?

Answer 21

neorocortex: layers 3, 5, 6 large pyramidal neurons
neurons > OLGs > astrocytes
arterial border-zone territories
hippocampal formation [Ca1, Sommer’s sector]
Cerebellar purkinje cells

Question 22

How does CV problem lead to brain death?

Answer 22

• diffuse cerebral edema increases ICP
• arterial inflow o brain stops –> get damage to medullar respiratory centers and need respirator
• brain tissue decomposition occurs: cerebral autolysis, liquefaction [tissue degeneration that occurs when perfusion ceases]
• no functional recovery possible

Question 23

What is different brain death vs anoxia?

Answer 23

anoxia = cortical necrosis but maintains blood flow to brainstem –> can cause persistent vegetative state but pt able to breath on their own