CT HEAD and ISCHEMIC CVA What 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 DISSAPEARING BASAL GANGLIA 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

Early CT is NOT a sensitive test in ischemic CVA 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