title: Abnormal intravoxel cerebral blood flow heterogeneity in human ischemic stroke determined by dynamic susceptibility contrast magnetic resonance imaging.
abstract: OBJECTIVE
  The determination of cerebral blood flow heterogeneity (FH) by dynamic susceptibility contrast (DSC) magnetic resonance imaging has recently been proposed as a tool to predict final infarct size in acute stroke. In this study, we describe the evolution of FH during the first week as well as its correlation to the patients' clinical status.
  
  
  METHODS
  Ten patients with ischemic stroke were studied with DSC MRI and diffusion-weighted imaging in hyperacute (<6 hours) phase, at 24 hours, and 1 week after symptom onset. In addition to intravoxel FH, cerebral blood volume (CBV), cerebral blood flow (CBF), and contrast agent mean transit time (MTT) were determined from DSC MRI. All patients were evaluated neurologically with National Institute of Health Stroke Scale concurrently with the imaging sessions.
  
  
  RESULTS
  All patients showed infarct growth, judged by diffusion-weighted imaging, during the week with simultaneous decrease in the sizes of FH, CBV, CBF, and MTT abnormalities. The FH abnormality was shown to be larger than CBV and CBF abnormalities at the hyperacute phase and 24 hours, but smaller than MTT abnormality in all 3 imaging sessions. The sizes of hyperacute FH, CBV, CBF, and MTT abnormalities correlated well with infarct size at 24 hours and at 1 week. Additionally, FH was the only perfusion parameter that correlated with the clinical score.
  
  
  CONCLUSIONS
  FH predicts infarct size equally well with the other perfusion parameters but is superior in correlation with the clinical score. FH can easily be incorporated to hyperacute stroke imaging without additional efforts.
authors.affiliation: HUS Helsinki Medical Imaging Center, University of Helsinki, Helsinki, Finland. jussi.perkio@hus.fi
authors.forename: Jussi
authors.initials: J
authors.lastname: Perkiö
authors.forename: Lauri
authors.initials: L
authors.lastname: Soinne
authors.forename: Leif
authors.initials: L
authors.lastname: Østergaard
authors.forename: Johanna
authors.initials: J
authors.lastname: Helenius
authors.forename: Aki
authors.initials: A
authors.lastname: Kangasmäki
authors.forename: Sami
authors.initials: S
authors.lastname: Martinkauppi
authors.forename: Oili
authors.initials: O
authors.lastname: Salonen
authors.forename: Sauli
authors.initials: S
authors.lastname: Savolainen
authors.forename: Markku
authors.initials: M
authors.lastname: Kaste
authors.forename: Turgut
authors.initials: T
authors.lastname: Tatlisumak
authors.forename: Hannu J
authors.initials: HJ
authors.lastname: Aronen
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000175:diagnosis*; D002560:Cerebrovascular Circulation; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000175:diagnosis*
chemical_list: D003287:Contrast Media