title: Carotid artery web and ischemic stroke: A case-control study.
abstract: OBJECTIVE
  To determine whether there is an association between carotid artery web and ischemic stroke.
  
  
  METHODS
  This was a single-center, age- and sex-matched, case-control study. Cases were consecutive patients with anterior circulation ischemic stroke of undetermined etiology (Trial of Org 10172 in Acute Stroke Treatment [TOAST] classification). Controls were consecutive patients with cerebral aneurysms, arteriovenous malformations, or primary intracerebral hemorrhages. Additional inclusion criteria were age <60 years and CT angiography of the neck. Two neuroradiologists diagnosed webs according to previously published criteria. One neuroradiologist also assessed for nonstenotic atherosclerotic plaque (carotid wall thickness ≥3 mm or intramural calcification). We used conditional logistic regression to estimate the odds ratio between carotid web and ischemic stroke and its 95% confidence interval.
  
  
  RESULTS
  Fifty-three of 62 cases (85%) were matched by age (within 1 year) and by sex to 102 controls. There was a carotid web in 4 of 53 cases (9.4%) vs 1 of 102 controls (1.0%, odds ratio = 8.0, 95% confidence interval = 1.2-67, p = 0.032). There was no significant difference in the prevalence of nonstenotic carotid atherosclerotic plaque between the case and control groups. There was agreement on diagnosis of web for 163 of 164 patients (99%) and 7 of 8 webs (88%), and the Cohen κ for interobserver agreement was 0.93.
  
  
  CONCLUSIONS
  There is an association between carotid artery web and ischemic stroke in patients who lack an alternative cause of stroke. Carotid web may be an underappreciated risk factor for stroke.
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Coutinho
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Sheldon
authors.initials: S
authors.lastname: Derkatch
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Alphonse R J
authors.initials: AR
authors.lastname: Potvin
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: George
authors.initials: G
authors.lastname: Tomlinson
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Leanne K
authors.initials: LK
authors.lastname: Casaubon
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Frank L
authors.initials: FL
authors.lastname: Silver
authors.affiliation: From the Division of Neuroradiology (J.M.C., S.D., D.M.M.), Department of Medical Imaging, and Division of Neurology (A.R.J.P., L.K.C., F.L.S.), Department of Medicine, University of Toronto and University Health Network; Dalla Lana School of Public Health (G.T.), University of Toronto; and Department of Medicine (G.T.), University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada. danny.mandell@uhn.ca.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Mandell
mesh_terms: D000328:Adult; D002545:Brain Ischemia / Q000150:complications / Q000453:epidemiology*; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D002533:Cerebral Angiography; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000150:complications / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000209:etiology; D014057:Tomography, X-Ray Computed