Stroke

Question 1

Percent of ischemic strokes attributed to cardioembolic

Answer 1

30%?

Question 2

Stroke code noncontrast CT features to look for

Answer 2

• Blood or no blood? If blood IVH involvement?
• Clear hypodensities?
  > Obscuration of lentiform nucleus
  > ASPECT score
• Loss of gray-white differentiation
  > Insular ribbon sign
  > Cortical ribbon sign
• Edema (loss of sulci)
• Other signs:
  > Hyperdense artery sign
  > MCA dot sign

Question 3

Poor prognostic factors of intracerebral hemorrhage

Answer 3

Large volume (>60cc)
Blend sign - hemorrhage with hyper dense and hypodense regions
Black hole sign - hypodense region surrounded by a hyper dense region not connected with the adjacent brain tissue
Island sign - three scattered small hemorrhages separate from the main hemorrhage

Question 4

Describe the pathophysiology of ischemia on CT

Answer 4

Severe cerebral ischemia (blood flow < 10ml/100g/min) causes brain tissue water to shift from extra cellular to the intracellular space causing hypoattenuation on CT

Normally gray matter appears brighter on CT than white matter
With ischemia, gray matter becomes edema to us, loses signal and starts to become darker on CT resulting in gray-white matter differentiation

Question 5

How early can ischemic changes be seen on CT?

Answer 5

As early as 1 hour after stroke onset

Question 6

Post minor ischemic stroke or TIA antiplatelet plan

Answer 6

Aspirin + clopidogrel (placid) for 10-21 days

DAPT recommended for TIA with ABCD2 score of 4 or greater
Minor stroke = NIHSS = 3

Aspirin 75-81mg daily
Clopidogrel 75mg daily

Aspirin whole w/o food
Clopidogrel can be crushed or split and taken with food