Predicting final infarct size using acute and subacute multiparametric MRI measurements in patients with ischemic stroke.
OBJECTIVE
To identify early MRI characteristics of ischemic stroke that predict final infarct size three months poststroke.


METHODS
Multiparametric MRI (multispin echo T2-weighted [T2W] imaging, T1-weighted [T1W] imaging, and diffusion-weighted imaging [DWI]) was performed acutely (<24 hours), subacutely (three to five days), and at three months. MRI was processed using maps of apparent diffusion coefficient (ADC), T2, and a self-organizing data analysis (ISODATA) technique. Analyses began with testing for individual MRI parameter effects, followed by multivariable modeling with assessment of predictive ability (R(2)) on final infarct size.


RESULTS
A total of 45 patients were studied, 15 of whom were treated with tissue plasminogen activator (tPA) before acute MRI. The acute DWI and DWI-ISODATA mismatch lesion size, and the interactions of ADC, T2, and T2W imaging lesion with tPA remained in the final multivariable model (R(2) = 70%). A large acute DWI lesion or DWI < ISODATA lesion independently predicted increase in the final infract size, with predictive ability 68%. Predictive ability increased (R(2) = 83%) when subacute MRI parameters were included along with acute DWI, DWI-ISODATA mismatch, and acute T2W image lesion size by tPA treatment interaction. Subacute DWI > acute DWI lesion size predicted an increased final infarct size (P < 0.01).


CONCLUSIONS
Acute-phase DWI and DWI-ISODATA mismatch strongly predict the final infarct size. An acute-to-subacute DWI lesion size change further increases the predictive ability of the model.
Lu
Mei
M
Department of Biostatistics and Research Epidemiology, Henry Ford Health System, Detroit, Michigan 48202, USA. mlu1@hfhs.org
Mitsias
Panayiotis D
PD
Ewing
James R
JR
Soltanian-Zadeh
Hamid
H
Bagher-Ebadian
Hassan
H
Zhao
Qingming
Q
Oja-Tebbe
Nancy
N
Patel
Suresh C
SC
Chopp
Michael
M
D000208:Acute Disease; D002545:Brain Ischemia / Q000473:pathology*; D002544:Cerebral Infarction / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011237:Predictive Value of Tests