title: Fluid-Attenuated Inversion Recovery Hyperintensity Is Associated with Hemorrhagic Transformation following Reperfusion Therapy.
abstract: BACKGROUND
  It is still controversial whether early fluid-attenuated inversion recovery (FLAIR) hyperintensity within acute ischemic lesions carries the risk of hemorrhagic transformation (HT) after reperfusion therapy. Furthermore, the association between the location of FLAIR hyperintensity and HT has not been investigated.
  
  
  METHODS
  We retrospectively reviewed patients who underwent reperfusion therapy within 6 hours of stroke onset and magnetic resonance imaging including a FLAIR sequence before completing reperfusion therapy. FLAIR hyperintensity within the diffusion-weighted imaging (DWI) lesion was rated qualitatively, and HT was assessed on follow-up gradient echo imaging. The location of the FLAIR change and HT was classified as subcortical, cortical, or cortico-subcortical.
  
  
  RESULTS
  Of 134 patients with acute ischemic stroke included in this study, early FLAIR changes within DWI lesions were identified in 56 (41.8%) patients, and HT was noted in 51 (38.1%) patients. FLAIR change was independently associated with HT (odds ratio: 4.37, 95% confidence interval: 1.72-11.12). Geographically, 48.2% of the patients with a FLAIR change developed a matched HT (restricted to the region with the FLAIR change), and the risk of HT was further increased in patients with a FLAIR change in the cortico-subcortical region (68.8%).
  
  
  CONCLUSIONS
  In patients in the acute stage of stroke, an early FLAIR change is associated with the risk of HT following reperfusion therapy with a highly matched geographic relationship and common risk factors. Thus, identification of FLAIR change may be a useful surrogate marker to assess the likelihood of subsequent HT in patients treated with reperfusion therapy.
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors: Sung-Ho
authors: SH
authors: Ahn
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors: Bum Joon
authors: BJ
authors: Kim
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors: Yeon-Jung
authors: YJ
authors: Kim
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors: Sun U
authors: SU
authors: Kwon
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors: Jong S
authors: JS
authors: Kim
authors: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. Electronic address: dwkang@amc.seoul.kr.
authors: Dong-Wha
authors: DW
authors: Kang
mesh_terms: D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging; D002545:Brain Ischemia / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*; D002533:Cerebral Angiography; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D012306:Risk; D020521:Stroke / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator
keywords: Stroke; hemorrhage; magnetic resonance imaging; reperfusion