title: Intravenous Thrombolysis for Acute Ischemic Stroke due to Cervical Internal Carotid Artery Occlusion.
abstract: BACKGROUND
  Internal carotid artery (ICA) occlusions are poorly responsive to intravenous thrombolysis with tissue plasminogen activator (IV-tPA) in acute ischemic stroke (AIS). Most study populations have combined intracranial and extracranial ICA occlusions for analysis; few have studied purely cervical ICA occlusions. We evaluated AIS patients with acute cervical ICA occlusion treated with IV-tPA to identify predictors of outcomes.
  
  
  METHODS
  We studied 550 consecutive patients with AIS who received IV-tPA and identified 100 with pure acute cervical ICA occlusion. We evaluated the associations of vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score, and leptomeningeal collateral vessel status via 3 different grading systems, with functional recovery at 90 days, mortality, recanalization of the primary occlusion, and symptomatic intracranial hemorrhage (SICH). Modified Rankin Scale score 0-1 was defined as an excellent outcome.
  
  
  RESULTS
  The 100 patients had mean age of 67.8 (range 32-96) and median NIHSS score of 19 (range 4-33). Excellent outcomes were observed in 27% of the patients, SICH in 8%, and mortality in 21%. Up to 54% of the patients achieved recanalization at 24 hours. On ordinal regression, good collaterals showed a significant shift in favorable outcomes by Maas, Tan, or ASPECTS collateral grading systems. On multivariate analysis, good collaterals also showed reduced mortality (OR .721, 95% CI .588-.888, P = .002) and a trend to less SICH (OR .81, 95% CI .65-1.007, P = .058). Interestingly, faster treatment was also associated with favorable functional recovery (OR 1.028 per minute, 95% CI 1.010-1.047, P = .001).
  
  
  CONCLUSIONS
  Improved outcomes are seen in patients with early acute cervical ICA occlusion and better collateral circulation. This could be a valuable biomarker for decision making.
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore. Electronic address: leonard_ll_yeo@nuhs.edu.sg.
authors.forename: Leonard L L
authors.initials: LL
authors.lastname: Yeo
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Wan Yee
authors.initials: WY
authors.lastname: Kong
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Prakash
authors.initials: P
authors.lastname: Paliwal
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Hock L
authors.initials: HL
authors.lastname: Teoh
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Raymond C
authors.initials: RC
authors.lastname: Seet
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Derek
authors.initials: D
authors.lastname: Soon
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Rahul
authors.initials: R
authors.lastname: Rathakrishnan
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Venetia
authors.initials: V
authors.lastname: Ong
authors.affiliation: Department of Neurology, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine and School of Medical Technology, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Tsong-Hai
authors.initials: TH
authors.lastname: Lee
authors.affiliation: College of Medicine and School of Medical Technology, Chang Gung University, Taoyuan, Taiwan; Division of Neuroradiology, Department of Medical Imaging and Intervention, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Ho-Fai
authors.initials: HF
authors.lastname: Wong
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Bernard P L
authors.initials: BP
authors.lastname: Chan
authors.affiliation: Department of Computer Science, National University of Singapore, Singapore.
authors.forename: Wee Kheng
authors.initials: WK
authors.lastname: Leow
authors.affiliation: Department of Computer Science, National University of Singapore, Singapore.
authors.forename: Cheng
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Department of Diagnostic Imaging, National University Health System, Singapore.
authors.forename: Eric
authors.initials: E
authors.lastname: Ting
authors.affiliation: Department of Diagnostic Imaging, National University Health System, Singapore.
authors.forename: Anil
authors.initials: A
authors.lastname: Gopinathan
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore.
authors.forename: Benjamin Y Q
authors.initials: BY
authors.lastname: Tan
authors.affiliation: Division of Neurology, Department of Medicine, National University Health System, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Sharma
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000503:physiopathology; D016893:Carotid Stenosis / Q000150:complications* / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D016009:Chi-Square Distribution; D003097:Collateral Circulation; D016208:Databases, Factual; D004185:Disability Evaluation; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007262:Infusions, Intravenous; D020300:Intracranial Hemorrhages / Q000139:chemically induced; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D020127:Recovery of Function; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D020521:Stroke / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality; D015912:Thrombolytic Therapy / Q000009:adverse effects / Q000401:mortality; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents
keywords: Acute ischemic care; CT angiography; intracranial collaterals; thrombolysis