title: Early diffusion-weighted imaging reversal after endovascular reperfusion is typically transient in patients imaged 3 to 6 hours after onset.
abstract: OBJECTIVE
  The aim of this study was to assess the frequency and extent of early diffusion-weighted imaging (DWI) lesion reversal after endovascular therapy and to determine whether early reversal is sustained or transient.
  
  
  METHODS
  MRI with DWI perfusion imaging was performed before (DWI 1) and within 12 hours after (DWI 2) endovascular treatment; follow-up MRI was obtained on day 5. Both DWIs were coregistered to follow-up MRI. Early DWI reversal was defined as the volume of the DWI 1 lesion that was not superimposed on the DWI 2 lesion. Permanent reversal was the volume of the DWI 1 lesion not superimposed on the day 5 infarct volume. Associations between early DWI reversal and clinical outcomes in patients with and without reperfusion were assessed.
  
  
  RESULTS
  A total of 110 patients had technically adequate DWI before endovascular therapy (performed median [interquartile range], 4.5 [2.8-6.2] hours after onset); 60 were eligible for this study. Thirty-two percent had early DWI reversal >10 mL; 17% had sustained reversal. The median volume of permanent reversal at 5 days was 3 mL (interquartile range, 1.7-7.0). Only 2 patients (3%) had a final infarct volume that was smaller than their baseline DWI lesion. Early DWI reversal was not an independent predictor of clinical outcome and was not associated with early reperfusion.
  
  
  CONCLUSIONS
  Early DWI reversal occurred in about one third of patients after endovascular therapy; however, reversal was often transient and was not associated with a significant volume of tissue salvage or favorable clinical outcome.
authors.affiliation: From the Stanford Stroke Center, Stanford University School of Medicine, CA.
authors.forename: Manabu
authors.initials: M
authors.lastname: Inoue
authors.forename: Michael
authors.initials: M
authors.lastname: Mlynash
authors.forename: Soren
authors.initials: S
authors.lastname: Christensen
authors.forename: Hayley M
authors.initials: HM
authors.lastname: Wheeler
authors.forename: Matus
authors.initials: M
authors.lastname: Straka
authors.forename: Aaryani
authors.initials: A
authors.lastname: Tipirneni
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Kemp
authors.forename: Greg
authors.initials: G
authors.lastname: Zaharchuk
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Olivot
authors.forename: Roland
authors.initials: R
authors.lastname: Bammer
authors.forename: Maarten G
authors.initials: MG
authors.lastname: Lansberg
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Albers
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000473:pathology* / Q000628:therapy*; D002548:Cerebral Revascularization; D002560:Cerebrovascular Circulation; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D018450:Disease Progression; D057510:Endovascular Procedures; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012008:Recurrence; D016896:Treatment Outcome
keywords: cerebral infarction; diffusion MRI; magnetic resonance imaging; thrombolytic therapy