Cerebrovascular Disease Flashcards
Hypoxic/Ischemic separates into those conditions that involve a lack of oxygen delivery to the entire brain, ______ischemia (e.g. watershed infarcts, selective vulnerability), and those affected by a lack of blood flow and oxygen delivery to an area of the brain, ______ ischemia (e.g. thrombotic or embolic infarcts)
Hypoxic/Ischemic separates into those conditions that involve a lack of oxygen delivery to the entire brain, global ischemia (e.g. watershed infarcts, selective vulnerability), and those affected by a lack of blood flow and oxygen delivery to an area of the brain, focal ischemia (e.g. thrombotic or embolic infarcts)
Hypertension is associated with hemorrhages due to ______ in the wall of affected blood vessels (e.g. basal ganglia and pons) perhaps due to microaneurysms, lacunar infarcts, and encephalopathy/dementia.
Hypertension is associated with hemorrhages due to breaks in the wall of affected blood vessels (e.g. basal ganglia and pons) perhaps due to microaneurysms, lacunar infarcts, and encephalopathy/dementia.
Insufficient oxygen delivery is known as _____
Hypoxic injury or ischemia
When blood exits through the vessel wall, it is called ____
hemorrhage
_____ is an example of global ischemia
cardiac arrest
Pathology of global ischemia:
Selective vulnerability
_____ Infarction
Laminar Necrosis
_____ Brain
Pathology of global ischemia:
Selective vulnerability
Watershed Infarction
Laminar Necrosis
Respirator Brain
Laminar necrosis: death of cells in the ____ cortex in a ___-like pattern
Laminar necrosis: death of cells in the cerebral cortex in a band-like pattern
Areas most at risk for oxygen deficit:
1. _________ – Sommer sector (most susceptible)
2. Cerebellum – _______ cells (2nd most susceptible)
3. Cortex
Areas most at risk for oxygen deficit:
- Hippocampus – Sommer sector (most susceptible)
- Cerebellum – Purkinje cells (2nd most susceptible)
- Cortex
What is seen in this image?
global ischemia: red neuron change
What is seen in this image?
Watershed infarction
Watershed infarction
Global ischemia injury
Occurs with ______and subsequent reperfusion
Areas between arterial territory are dependent on flow from both arteries (no terminal anastomoses)
With low flow, this area becomes ischemic
Reperfusion causes leaking of blood through damaged vessels – ______
Often bilateral
Watershed infarction
Global ischemia injury
Occurs with hypoperfusion and subsequent reperfusion
Areas between arterial territory are dependent on flow from both arteries (no terminal anastomoses)
With low flow, this area becomes ischemic
Reperfusion causes leaking of blood through damaged vessels – hemorrhagic
Global ischemia- Laminar Necrosis:
- Layers of the cortex vary in their sensitivity to ischemia/hypoxia
- Penetrating vessels from _____ form plexus in layers V and VI (Rubin)
- Decrease in blood pressure leads to decreased _____ in plexus
- Necrosis in a _____ pattern results
Global ischemia- Laminar Necrosis:
- Layers of the cortex vary in their sensitivity to ischemia/hypoxia
- Penetrating vessels from pia form plexus in layers V and VI (Rubin)
- Decrease in blood pressure leads to decreased perfusion in plexus
- Necrosis in a linear pattern results
What does this image show?
Laminar necrosis
Respirator Brain
- With severe ischemic or other injury, brain _____ is severe
- With edema, intracranial pressure is markedly ____
- If ICP exceeds _____pressure, blood flow to the brain (hemispheres and other parts of brain) stops
- Brain undergoes autolysis (i.e. no blood flow)
- EEG shows no cerebral activity. This correlates with brain death.
Respirator Brain
- With severe ischemic or other injury, brain edema is severe
- With edema, intracranial pressure is markedly increased
- If ICP exceeds venous pressure, blood flow to the brain (hemispheres and other parts of brain) stops
- Brain undergoes autolysis (i.e. no blood flow)
- EEG shows no cerebral activity. This correlates with brain death.
Focal Ischemia- Atherosclerosis with thrombosis
- _____ vessels
- _____ onset possible (occlusion doesn’t have to be sudden)
- Anemic/Pale
- Less likely to reperfuse – less likely to be _____
- Usually single territory
Focal Ischemia- Atherosclerosis with thrombosis
- Larger vessels
- Slower onset possible (occlusion doesn’t have to be sudden)
- Anemic/Pale
- Less likely to reperfuse – less likely to be hemorrhagic
- Usually single territory
Focal Ischemia- Embolic stroke:
- Source – Clots from elsewhere
- Mural Thrombus
- Heart valves
- Through openings in heart (e.g. foramen ovale) – from vessels in body
- Carotid arteries
- Occlusion possible from air, fat, and other substances
- Often ______
- Blood clots are more likely to _____than thrombotic
- Often _____ (from shower of emboli)
Focal Ischemia- Embolic stroke:
- Source – Clots from elsewhere
- Mural Thrombus
- Heart valves
- Through openings in heart (e.g. foramen ovale) – from vessels in body
- Carotid arteries
- Occlusion possible from air, fat, and other substances
- Often hemorrhagic
- Blood clots are more likely to dissolve than thrombotic
- Often multiple (from shower of emboli)