Mns: Cerebrovascular Pathology

Front 1

what are the 3 disorders affecting the balance between brain volume and the fixed boundaries of the skull?

Back 1

1. Edema
2. Expanding mass lesions
3. Hydrocephalus

Front 2

what is cerebral edema?

Back 2

an increase in brain volume caused by an absolute increase in cerebral tissue water content

Front 3

what are the two main types of edema?

Back 3

vasogenic and cytotoxic

Front 4

Describe vasogenic edema?

Back 4

an increase in extracellular fluid volume due to the presence of a brain insult which causes increased permeability of brain capillary endothelial cells to large molecules

Front 5

why doesnt the leakage that results in vasogenic edema just diffuse back into circulation like it would in other tissue?

Back 5

there are no lymphatics in the brain and glial cells block the return of fluid back into the vasculature of the brain (BBB)

Front 6

describe cytotoxic edema?

Back 6

swelling of all the cellular elements of the brain caused by presence of acute cerebral insult which results in failure of ATP-dependent sodium and calcium pumps

Front 7

what is the result of knocking out sodiuma and Ca++ pumps in glia, neurons, and vascular endothelium during cytotoxic edema?

Back 7

cells retain sodium causing swelling and Ca++ accumulation results in activation of phospholipases which leads to formation of oxygen free radicals which damage brain tissue

Front 8

what rank does stroke hold in the hierarchy of death causing medical events in adults?

Back 8

3rd behind cardiovascular events and cancer

Front 9

what are the two types of stroke?

Back 9

1. ischemic
2. hemorrhagic

Front 10

80 percent of strokes are said to be which type?

Back 10

ischemic

Front 11

the most deadly type of stroke is?

Back 11

hemorrhagic (20% of strokes)

Front 12

what would be injured with a thrombosis of striate artery?

Back 12

infarction of the internal capsul

Front 13

what would be the result of a occulsion at the trifurcation of the cerebral artery?

Back 13

zone of cortical infarction

Front 14

what would cut of blood supply to both the cortex and the internal capsul?

Back 14

thrombotic occlusion of the internal carotid artery

Front 15

Focal brain injury due to complete and prolonged ischemia is called?

Back 15

cerebral infarction

Front 16

what is a "red infarct"?

Back 16

when the clot causing the infarct is busted and the necrotic tissue is reperfused causing a red appearance

Front 17

after an infarct, the area of total ischemia and tissue necrosis which is irreversible is called?

Back 17

central core

Front 18

after an infarct, the area of borderline ischemic tissue which receives collateral circulation is called?

Back 18

the penumbra

Front 19

the goal of administering tPA and other clot busting drugs is to?

Back 19

reperfuse the penumbra and hopefully retain most of the brain tissue and structure there

Front 20

what is edema that evolves after an infarct over minutes to hours and may be reversible called?

Back 20

cytotoxic edema

Front 21

what is edema that occurs over hours to days, and is considered an irreversibly damaging process called?

Back 21

vasogenic

Front 22

why does necrotic brain tissue cause cyotgenic edema?

Back 22

it releases osmotically active substances (arachidonic acid, electrolytes, lactic acid) from the necrotic brain tissue

Front 23

what time frame does pronounced edema occure in following a stroke?

Back 23

3-4 days post stroke event

Front 24

what is death from a massive hemispheric infarct really cause by?

Back 24

the edema not the necrosis

Front 25

describe the pathology of a cerebral infarct during the first 24 hours?

Back 25

+poorly demarcated area of softening
+imaging may be negative

Front 26

describe the pathology of a cerebral infarct during 1-7 days?

Back 26

+infarct becomes clearly defined
+peak edema (3-4 days) the infarct appears hyopdense and bright by MRI

Front 27

describe the pathology of a cerebral infarct during > 1 week?

Back 27

necrotic tissue is destroyed by marophages and replaced by by a gliotic cavity (gliosis instead of fibrosis)

Front 28

what causes the "swiss cheese" appearance of the depper parts of the brain?

Back 28

small infarcts of the deep penetrating branches of the cerebral arteries

Front 29

what type of patient is most likely to have "swiss cheese" infarct patterns?

Back 29

diabetics and hypertensive

Front 30

even though a lacunar infarct can cause serious neurological defects (even as severe as the much larger cerebral infarcts) why is it not as life threatening?

Back 30

it doesnt cause the massive cerebral edema that occurs around days 3-4 with cerebral infarcts

Front 31

if you have a venous infarction what type of stroke will it be and where will it most likely occure?

Back 31

hemorrhagic in the white matter or the white-grey matter junction

Front 32

if you see parasagittal hemorrhage from a venous infarct where is that infarct most likely to have occured?

Back 32

the superior sagittal sinus

Front 33

A focal neurological deficit that lasts less than 24 hours is called a?

Back 33

transient ischemic attack

Front 34

what is the usual cause of transient ischemic attack?

Back 34

emboli that break up soon after causing occlusion

Front 35

describe the level of permanent damage with transient ischemic attacks?

Back 35

NONE <-- big qualifier