title: ApoE polymorphism and acute stroke: a study with diffusion- and perfusion-weighted MRI and MR angiography.
abstract: OBJECTIVE
  We examined whether the apolipoprotein E (ApoE) allele epsilon4 influences imaging findings in stroke as assessed by diffusion- (DWI) and perfusion-weighted (PWI) magnetic resonance imaging, and MR angiography (MRA).
  
  
  METHODS
  Eight ApoE epsilon4 carriers and 15 non-carriers with acute ischemic stroke in the anterior circulation underwent DWI, PWI, and MRA within 24 h of stroke. DWI and PWI were repeated a week later. The apparent diffusion coefficient, relative cerebral volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time were measured in three subregions on day one.
  
  
  RESULTS
  In the ischemic core and the area of infarct growth, rCBV values were significantly higher in the epsilon4 carriers compared with the non-carriers. Based on the MRA findings, collateral blood flow was better in the epsilon4 carriers than in the non-carriers. Under the comparable severity of hypoperfusion, the hypoperfused area proceeded to infarction later or did not proceed to infarction at all in the non-carriers.
  
  
  CONCLUSIONS
  These preliminary data suggest that in the ApoE allele epsilon4 carriers the threshold for the brain tissue to survive hypoperfusion versus to proceed to infarction seems to be different from that of the non-carriers.
authors.affiliation: Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Nuutinen
authors.forename: M P
authors.initials: MP
authors.lastname: Laakso
authors.forename: J O
authors.initials: JO
authors.lastname: Karonen
authors.forename: S
authors.initials: S
authors.lastname: Soimakallio
authors.forename: H J
authors.initials: HJ
authors.lastname: Aronen
authors.forename: R L
authors.initials: RL
authors.lastname: Vanninen
mesh_terms: D000208:Acute Disease; D000368:Aged; D053327:Apolipoprotein E4 / Q000235:genetics; D001057:Apolipoproteins E / Q000235:genetics*; D001921:Brain / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology*; D002545:Brain Ischemia / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000235:genetics; D004252:DNA Mutational Analysis; D038524:Diffusion Magnetic Resonance Imaging; D018450:Disease Progression; D005260:Female; D005820:Genetic Testing; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011110:Polymorphism, Genetic / Q000235:genetics*; D011237:Predictive Value of Tests; D020521:Stroke / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology
chemical_list: D053327:Apolipoprotein E4; D001057:Apolipoproteins E