title: Comparison of MRI-based thrombolysis for patients with middle cerebral artery occlusion<or=3 h and 3-6 h.
abstract: OBJECTIVE
  To investigate the outcomes of magnetic resonance imaging (MRI)-based thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute middle cerebral artery (MCA) occlusion in 3-6 hours.
  
  
  METHODS
  MRI-selected patients (n=15) with acute ischemic stroke in MCA divided into two groups (<or=3 h and 3-6 h) were treated with intravenous rt-PA. MR was performed before rt-PA, at 24 hours, 7 days, and 14 days after stroke. Recanalization was assessed 24 h after thrombolysis, and clinical status was evaluated before rt-PA treatment, 6 hours, 24 hours, 7 days, and 14 days after thrombolysis by the National Institutes of Health Stroke Scale (NIHSS). Modified rankin scale (MRS) was used to assess clinical outcome at 30 and 90 days after thrombolysis.
  
  
  RESULTS
  There was no significant between <or=3 h and 3-6 h group in length of hospital stay, recanalization, MRS, and favorable outcome at 90 days. Recanalization within 24 hours occurred in 9 (60%), and nonrecanalization in 6 (40%). One patient in recanalization group and three in nonrecanalization group had an asymptomatic intracranial hemorrhage (ICH) within 24 h after thrombolysis (P=0.235). Recanalization with thrombolysis was associated with a better outcome regardless of the time point of rt-PA treatment. Comparison with nonrecanalization group, recanalization was also associated with a lower NIHSS score at 14 days (P=0.003), a lower TIMI grade at 7 days (P<0.001), and a shorter length of hospital stay (P=0.018).
  
  
  CONCLUSIONS
  Our study suggested that MR-based thrombolysis using rt-PA was safe and reliable in patients with acute MCA occlusion in 3-6 hours.
authors.affiliation: Department of Radiology, The Sixth Affiliated People's Hospital, Shanghai Jiao Tong University, Shanghai, China. leeyuehuaxp@gmail.com
authors.forename: Yue-Hua
authors.initials: YH
authors.lastname: Li
authors.forename: Ming-Hua
authors.initials: MH
authors.lastname: Li
authors.forename: Zhen-Guo
authors.initials: ZG
authors.lastname: Zhao
authors.forename: Qing-Ke
authors.initials: QK
authors.lastname: Bai
mesh_terms: D000368:Aged; D002533:Cerebral Angiography; D038524:Diffusion Magnetic Resonance Imaging; D004334:Drug Administration Schedule; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis* / Q000188:drug therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D015912:Thrombolytic Therapy / Q000379:methods*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator