title: Thrombus Length Estimation on Delayed Gadolinium-Enhanced T1.
abstract: OBJECTIVE
  Previous studies revealed a close relationship between thrombus length and recanalization rate after intravenous thrombolysis (IVT). As a novel approach, we prospectively adjusted the order of sequence acquisition to obtain delayed gadolinium-enhanced T1 (dGE-T1) and thereby assess thrombus length on dGE-T1 to evaluate its predictive value for recanalization after IVT.
  
  
  METHODS
  We reviewed prospectively collected clinical and imaging data from acute ischemic stroke patients with middle cerebral artery occlusion who underwent multimodal magnetic resonance imaging before and 24 hours after IVT. Perfusion-weighted imaging was performed followed by conventional T1. We measured thrombus length on dGE-T1 and examined its association with middle cerebral artery recanalization.
  
  
  RESULTS
  Of the included 74 patients, the median age was 66 years and 28 (37.8%) were women. Thrombus length was 8.18±4.56 mm on dGE-T1, which was an acceptable predictor for no recanalization (odds ratio, 1.196; 95% confidence interval, 1.015-1.409; P=0.033), with a receiver-operator characteristic of 0.732 (95% confidence interval, 0.619-0.845; P=0.001). The optimal cut-off point was identified at 6.77 mm, which yielded a sensitivity of 77.8%, a specificity of 57.9%, and an odds ratio of 4.81 (95% confidence interval, 1.742-13.292; P=0.002). Moreover, no one achieved recanalization after IVT when length of thrombus exceeded 14 mm on dGE-T1.
  
  
  CONCLUSIONS
  The dGE-T1, obtained by simply adjusting scanning order in multimodal magnetic resonance imaging protocol, is a useful tool for thrombus length estimation and middle cerebral artery recanalization prediction after IVT.
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.).
authors.forename: Shenqiang
authors.initials: S
authors.lastname: Yan
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.).
authors.forename: Qingmeng
authors.initials: Q
authors.lastname: Chen
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.).
authors.forename: Mengjun
authors.initials: M
authors.lastname: Xu
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.).
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Sun
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.).
authors.forename: David S
authors.initials: DS
authors.lastname: Liebeskind
authors.affiliation: From the Department of Neurology (S.Y., Q.C., M.X., M.L.) and Radiology (J.S.), The 2nd Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China; and Department of Neurology, University of California-Los Angeles Stroke Center (D.S.L.). loumingxc@vip.sina.com.
authors.forename: Min
authors.initials: M
authors.lastname: Lou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage; D005500:Follow-Up Studies; D005682:Gadolinium / Q000008:administration & dosage; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D012189:Retrospective Studies; D015912:Thrombolytic Therapy / Q000379:methods; D013927:Thrombosis / Q000000981:diagnostic imaging* / Q000188:drug therapy; D013997:Time Factors
chemical_list: D005343:Fibrinolytic Agents; D005682:Gadolinium
keywords: artifact; magnetic resonance imaging; middle cerebral artery; stroke; thrombolytic therapy