CT HEAD and ISCHEMIC CVAWhat to look for on the early scan??

“Doctor, I think I've gone and occluded my MCA again”

Xray rounds Nov 14, 2002

Rob Hall PGY3

What is the sensitivity of early CT head in ischemic CVA?

• Retrospective studies have looked at what % have findings at 6, 12, 24, 48hrs etc

• CANNOT BE DETERMINED– Size of infarct – Location of infarct– Time from infarct– Reader variability– 30% will never show on CT

CT HEAD and ISCHEMIC STROKE

• ISCHEMIC CVA

• CLINICAL SYNDROME + NO BLEED/TUMOR/MA/AVM

What are the early signs of ischemic CVA to look for???

•SEVEN SIGNS OF EARLY ISCHEMIC CVA

EARLY ISCHEMIC CVA

SIGN #1

• HYPODENSITY– Typically wedge

shaped hypodensity of affected territory due to edema

EARLY ISCHEMIC CVA

SIGN #2

• LOSS OF GREY - WHITE DIFFERENTIATION– Loss of the normal

distinction b/w the grey matter and the white matter

SIGN #3

• HYPERDENSE MCA SIGN– Due to acute occulsion

and swelling in the MCA

ANATOMY

• Caudate nucleus• Insular cortex• Putamen• Globus pallidus• Internal capsule

SIGNS #4 and #5

• INSULAR RIBBON SIGN– Loss of definition of

the insular cortex

• DISSAPEARING BASAL GANGLIA SIGN– Loss of definition b/w

the basal ganglia

SIGN #6

• SULCAL EFFACEMENT– Loss of definition of

the sulci due to edema

SIGN #7

SIGN #7

• VENTRICULAR COMPRESSION– Ventricles compressed

due to edema of overlying cortes

CONCLUSIONS

• Early CT is NOT a sensitive test in ischemic CVA

SEVEN SIGNS

• Hypodensity

• Loss of Grey - White differentiation

• Sulcal Effacement

• Hyperdense MCA sign

• Insular ribbon sign

• Disappearing Basal Ganglia sign

• Ventricular compression sign