title: Reliability of carotid doppler performed in a dedicated stroke prevention clinic.
abstract: BACKGROUND
  Doppler ultrasound (DUS) is used as a screening tool to assess internal carotid artery (ICA) disease. Recent reports suggest that the DUS may be inaccurate in over 28% of patients. We sought to evaluate the accuracy of DUS, when performed in a dedicated stroke prevention clinic (SPC).
  
  
  METHODS
  We retrospectively reviewed the charts of patients who had a DUS performed in our SPC, followed by conventional cerebral angiography. Three groups of patients were defined. Group 1 had DUS measured ICA stenosis of >50%; Group II had a DUS measured ICA stenosis of <50%; Group III had complete ICA occlusion on DUS.
  
  
  RESULTS
  Sixty-seven patients (69 arteries) were included in the study. There were 45 patients in Group I and based on the findings of cerebral angiography, carotid endarterectomy was considered inappropriate in only one patient--a misclassification rate of 2.2% (95% CI: 0 - 6.5%). Group II consisted of 19 patients and on cerebral angiography, none of these patients had a stenosis of >50%--a misclassification rate of 0%. Group III consisted of five patients in whom DUS showed complete ICA occlusion. The angiogram confirmed the occlusion in all five patients--a misclassification rate of 0%. Overall, misclassification rate was 1.45% (95% CI: 0 - 4.3%).
  
  
  CONCLUSIONS
  Doppler ultrasound when performed in a stroke prevention clinic (SPC), has a high accuracy in measuring ICA stenosis of >50%. Doppler ultrasound is reliable in detecting complete ICA occlusion and finally DUS is a reliable screening tool to rule out clinically significant ICA stenosis.
authors.affiliation: Division of Neurology, The Al Owen and Family Stroke Prevention Clinic, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Dean
authors.forename: H
authors.initials: H
authors.lastname: Lari
authors.forename: M
authors.initials: M
authors.lastname: Saqqur
authors.forename: N
authors.initials: N
authors.lastname: Amir
authors.forename: K
authors.initials: K
authors.lastname: Khan
authors.forename: M
authors.initials: M
authors.lastname: Mouradian
authors.forename: Abdul
authors.initials: A
authors.lastname: Salam
authors.forename: H
authors.initials: H
authors.lastname: Romanchuk
authors.forename: A
authors.initials: A
authors.lastname: Shuaib
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D002533:Cerebral Angiography; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital; D015203:Reproducibility of Results; D012189:Retrospective Studies; D020521:Stroke / Q000517:prevention & control*; D018608:Ultrasonography, Doppler