Prediction of final infarct volume on subacute MRI by quantifying cerebral edema in ischemic stroke.
Final infarct volume in stroke trials is assessed on images obtained between 30 and 90 days after stroke onset. Imaging at such delayed timepoints is problematic because patients may be lost to follow-up or die before the scan. Obtaining an early assessment of infarct volume on subacute scans avoids these limitations; however, it overestimates true infarct volume because of edema. The aim of this study was to develop a novel approach to quantify edema so that final infarct volumes can be approximated on subacute scans. We analyzed data from 20 stroke patients (median age, 75 years) who had baseline, subacute (fu5d) and late (fu90d) MRI scans. Edema displaces CSF from sulci and ventricles; therefore, edema volume was estimated as change in CSF volume between baseline and spatially coregistered fu5d ADC maps. The median (interquartile range, IQR) estimated edema volume was 13.3 (7.5-37.7) mL. The fu5d lesion volumes correlated well with fu90d infarct volumes with slope: 1.24. With edema correction, fu5d infarct volumes are in close agreement, slope: 0.97 and strongly correlated with actual fu90d volumes. The median (IQR) difference between actual and predicted infarct volumes was 0.1 (-3.0-5.7) mL. In summary, this novel technique for estimation of edema allows final infarct volume to be predicted from subacute MRI.
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.|2 Department of Biomedical Engineering, University of Memphis, Memphis, TN, USA.|3 Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA.
Aaryani
A
Tipirneni-Sajja
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Soren
S
Christensen
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Matus
M
Straka
4 Department of Neurology, Showa University Fujigaoka Hospital, Yokohama, Japan.
Manabu
M
Inoue
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Maarten G
MG
Lansberg
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Michael
M
Mlynash
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Roland
R
Bammer
5 Department of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
Mark W
MW
Parsons
6 Florey Neuroscience Institutes, Austin Health, University of Melbourne, Melbourne, VIC, Australia.
Geoffrey A
GA
Donnan
7 Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia.
Stephen M
SM
Davis
1 Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA.
Gregory W
GW
Albers
D000368:Aged; D001929:Brain Edema / Q000000981:diagnostic imaging* / Q000209:etiology / Q000517:prevention & control; D002545:Brain Ischemia / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy; D002544:Cerebral Infarction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000517:prevention & control; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008954:Models, Biological; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D020521:Stroke / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000209:etiology; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage / Q000627:therapeutic use
D010959:Tissue Plasminogen Activator
Apparent diffusion coefficient; edema; infarct volume; magnetic resonance imaging; stroke; subacute