title: Severity of leukoaraiosis determines clinical phenotype after brain infarction.
abstract: OBJECTIVE
  To determine whether the extent of leukoaraiosis, a composite marker of baseline brain integrity, differed between patients with TIA with diffusion-weighted imaging (DWI) evidence of infarction (transient symptoms with infarction [TSI]) and patients with ischemic stroke.
  
  
  METHODS
  Leukoaraiosis volume on MRI was quantified in a consecutive series of 153 TSI and 354 ischemic stroke patients with comparable infarct volumes on DWI. We explored the relationship between leukoaraiosis volume and clinical phenotype (TIA or ischemic stroke) using a logistic regression model.
  
  
  RESULTS
  Patients with TSI tended to be younger (median age 66 vs 69 years, p = 0.062) and had smaller median normalized leukoaraiosis volume (1.2 mL, interquartile range [IQR] 0.2-4.7 mL vs 3.5 mL, IQR 1.2-8.6 mL, p < 0.001). In multivariable analysis controlling for age, stroke risk factors, etiologic stroke mechanism, infarct volume, and infarct location, increasing leukoaraiosis volume remained associated with ischemic stroke (odds ratio 1.05 per mL, 95%confidence interval 1.02-1.09, p = 0.004), along with infarct volume and infarct location.
  
  
  CONCLUSIONS
  The probability of ischemic stroke rather than TSI increases with increasing leukoaraiosis volume, independent of infarct size and location. Our findings support the concept that the integrity of white matter tracts connecting different parts of the brain could contribute to whether or not patients develop TSI or ischemic stroke in an event of brain infarction.
authors.affiliation: A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Room 2301, Charlestown, MA 02129, USA.
authors.forename: E M
authors.initials: EM
authors.lastname: Arsava
authors.forename: A
authors.initials: A
authors.lastname: Bayrlee
authors.forename: M
authors.initials: M
authors.lastname: Vangel
authors.forename: N S
authors.initials: NS
authors.lastname: Rost
authors.forename: J
authors.initials: J
authors.lastname: Rosand
authors.forename: K L
authors.initials: KL
authors.lastname: Furie
authors.forename: A G
authors.initials: AG
authors.lastname: Sorensen
authors.forename: H
authors.initials: H
authors.lastname: Ay
mesh_terms: D000368:Aged; D020520:Brain Infarction / Q000175:diagnosis* / Q000503:physiopathology*; D056324:Diffusion Tensor Imaging; D018450:Disease Progression; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D049292:Leukoaraiosis / Q000473:pathology* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index