title: Predicting final infarct size using acute and subacute multiparametric MRI measurements in patients with ischemic stroke.
abstract: 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.
authors.affiliation: Department of Biostatistics and Research Epidemiology, Henry Ford Health System, Detroit, Michigan 48202, USA. mlu1@hfhs.org
authors.forename: Mei
authors.initials: M
authors.lastname: Lu
authors.forename: Panayiotis D
authors.initials: PD
authors.lastname: Mitsias
authors.forename: James R
authors.initials: JR
authors.lastname: Ewing
authors.forename: Hamid
authors.initials: H
authors.lastname: Soltanian-Zadeh
authors.forename: Hassan
authors.initials: H
authors.lastname: Bagher-Ebadian
authors.forename: Qingming
authors.initials: Q
authors.lastname: Zhao
authors.forename: Nancy
authors.initials: N
authors.lastname: Oja-Tebbe
authors.forename: Suresh C
authors.initials: SC
authors.lastname: Patel
authors.forename: Michael
authors.initials: M
authors.lastname: Chopp
mesh_terms: 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