title: Evidence-based guideline: The role of diffusion and perfusion MRI for the diagnosis of acute ischemic stroke [RETIRED]: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology.
abstract: To assess the evidence for the use of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) in the diagnosis of patients with acute ischemic stroke.
  
  
  
  We systematically analyzed the literature from 1966 to January 2008 to address the diagnostic and prognostic value of DWI and PWI.
  
  
  
  DWI is established as useful and should be considered more useful than noncontrast CT for the diagnosis of acute ischemic stroke within 12 hours of symptom onset. DWI should be performed for the most accurate diagnosis of acute ischemic stroke (Level A); however, the sensitivity of DWI for the diagnosis of ischemic stroke in a general sample of patients with possible acute stroke is not perfect. The diagnostic accuracy of DWI in evaluating cerebral hemorrhage is outside the scope of this guideline. On the basis of Class II and III evidence, baseline DWI volumes probably predict baseline stroke severity in anterior territory stroke (Level B) but possibly do not in vertebrobasilar artery territory stroke (Level C). Baseline DWI lesion volumes probably predict (final) infarct volumes (Level B) and possibly predict early and late clinical outcome measures (Level C). Baseline PWI volumes predict to a lesser degree the baseline stroke severity compared with DWI (Level C). There is insufficient evidence to support or refute the value of PWI in diagnosing acute ischemic stroke (Level U).
authors.affiliation: National Institutes of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA.
authors.forename: P D
authors.initials: PD
authors.lastname: Schellinger
authors.forename: R N
authors.initials: RN
authors.lastname: Bryan
authors.forename: L R
authors.initials: LR
authors.lastname: Caplan
authors.forename: J A
authors.initials: JA
authors.lastname: Detre
authors.forename: R R
authors.initials: RR
authors.lastname: Edelman
authors.forename: C
authors.initials: C
authors.lastname: Jaigobin
authors.forename: C S
authors.initials: CS
authors.lastname: Kidwell
authors.forename: J P
authors.initials: JP
authors.lastname: Mohr
authors.forename: M
authors.initials: M
authors.lastname: Sloan
authors.forename: A G
authors.initials: AG
authors.lastname: Sorensen
authors.forename: S
authors.initials: S
authors.lastname: Warach
mesh_terms: D002545:Brain Ischemia / Q000175:diagnosis*; D019317:Evidence-Based Medicine; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020521:Stroke / Q000175:diagnosis*