title: Safety and efficacy of MRI-based thrombolysis in unclear-onset stroke. A preliminary report.
abstract: BACKGROUND
  Standard selection criteria for thrombolysis typically exclude patients with acute ischemic stroke with unclear onset. Multimodal MRI screening may be able to identify those with a favorable benefit-risk ratio for thrombolysis. We aimed to evaluate the safety and efficacy of MRI-based thrombolysis in unclear-onset stroke (UnCLOS).
  
  
  METHODS
  We reviewed the thrombolysis database registries from 3 medical centers in Korea. Subjects received thrombolysis with intravenous tissue plasminogen activator (tPA) or combined intravenous tPA and intra-arterial urokinase within 3 h, or intra-arterial urokinase within 6 h from symptom detection. For patients with UnCLOS, MRI-specific eligibility criteria (i.e. positive perfusion-diffusion mismatch and absence of well-developed fluid-attenuated inversion recovery changes of acute diffusion lesions) were applied. Rates of immediate and 5-day recanalization, early neurological improvement and symptomatic intracranial hemorrhage (ICH) within 48 h after treatment and 3-month modified Rankin Scale (mRS) scores were compared between patients with UnCLOS and those with clear-onset stroke (CLOS).
  
  
  RESULTS
  32 patients with UnCLOS and 223 patients with CLOS were included. Baseline characteristics were comparable between the two groups, except that the proportion of MRI screening was higher, and detection-to-door time and door-to-needle time were longer in the UnCLOS group (p < 0.01). Rates of recanalization (immediate, 81.3 vs. 63.1%; delayed, 80.6 vs. 69.1%), early neurological improvement (on day 1, 46.9 vs. 35.9%; on day 7, 50.0 vs. 49.3%), symptomatic ICH (6.3 vs. 5.8%) and 3-month outcome (mRS 0-1, 37.5 vs. 35.0%; mRS 0-2, 50.0 vs. 49.3%) did not differ between the UnCLOS and CLOS groups.
  
  
  CONCLUSIONS
  These preliminary results suggest that thrombolysis based on MRI criteria may safely be applied to acute stroke patients with unclear onset.
authors.affiliation: Department of Neurology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: A-Hyun
authors.initials: AH
authors.lastname: Cho
authors.forename: Sung-Il
authors.initials: SI
authors.lastname: Sohn
authors.forename: Moon-Ku
authors.initials: MK
authors.lastname: Han
authors.forename: Deok Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Jong S
authors.initials: JS
authors.lastname: Kim
authors.forename: Choong Gon
authors.initials: CG
authors.lastname: Choi
authors.forename: Chul-Ho
authors.initials: CH
authors.lastname: Sohn
authors.forename: Sun U
authors.initials: SU
authors.lastname: Kwon
authors.forename: Dae Chul
authors.initials: DC
authors.lastname: Suh
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Kim
authors.forename: Hee-Joon
authors.initials: HJ
authors.lastname: Bae
authors.forename: Dong-Wha
authors.initials: DW
authors.lastname: Kang
mesh_terms: D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging / Q000592:standards*; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000175:diagnosis; D018810:Magnetic Resonance Angiography / Q000592:standards*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D020521:Stroke / Q000628:therapy*; D015912:Thrombolytic Therapy / Q000592:standards*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use; D016896:Treatment Outcome; D014568:Urokinase-Type Plasminogen Activator / Q000627:therapeutic use
chemical_list: D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator