title: Serial FLAIR imaging after Gd-DTPA contrast: pitfalls in stroke trial magnetic resonance imaging.
abstract: BACKGROUND
  Most MRI protocols for stroke trials comprise 2 successive fluid-attenuated inversion-recovery (FLAIR) imaging acquisitions in which the first scan is done pre-Gd-DTPA contrast while the second is within the contrast clearance window.
  
  
  METHODS
  A 68-year-old male was diagnosed as having hyperacute right middle cerebral artery infarct and a subacute chronic small left occipital cortical infarct. The latter turned from hypointense to strikingly hyperintense on the second FLAIR image, resembling the picture of an acute-on-chronic infarction or hemorrhage. However, the second DWI and CT refuted either of these.
  
  
  CONCLUSIONS
  Image contrast using FLAIR in acute stroke trial imaging may also be affected by T1 effects of Gd-DTPA in chronic infarcts.
authors.affiliation: Department of Diagnostic Radiology, Singapore General Hospital, Outram Rd, Singapore 169608. helmut.rumpel@pacific.net.sg
authors.forename: Helmut
authors.initials: H
authors.lastname: Rumpel
authors.forename: Ling Ling
authors.initials: LL
authors.lastname: Chan
mesh_terms: D000208:Acute Disease; D000368:Aged; D016477:Artifacts; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D002543:Cerebral Hemorrhage / Q000175:diagnosis; D002908:Chronic Disease; D002986:Clinical Trials as Topic; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008657:Metabolic Clearance Rate; D020521:Stroke / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA