title: Preprocedural imaging strategies in symptomatic carotid artery stenosis.
abstract: BACKGROUND
  The benefit of carotid endarterectomy (CEA) over best medical therapy was established using intra-arterial angiography (IAA) for patient selection. Its cost, availability, and risk together with the emergence of newer imaging modalities have led to its replacement in the routine assessment of internal carotid artery (ICA) stenosis. The relative performance of these methods should dictate the optimum imaging strategy in symptomatic patients.
  
  
  METHODS
  A previous meta-analysis (NIHR Health Technology Assessment Programme) was reviewed. Medline and PubMed search was performed for relevant publications since 2006 together with a review of the references in retrieved publications.
  
  
  RESULTS
  Compared to IAA, the sensitivity and specificity for noninvasive imaging of a ≥70% to 99% ICA stenosis are duplex ultrasound (DUS): 0.89 (0.85-0.92) and 0.84 (0.77-0.89); time-of-flight magnetic resonance angiography (TOF-MRA): 0.88 (0.82-0.92) and 0.84 (0.76-0.97); contrast-enhanced MRA (CE-MRA): 0.94 (0.88-0.97) and 0.93 (0.89-0.96); and computed tomography angiography: 0.77 (0.68-0.84) and 0.95 (0.91-0.97), respectively. A policy of initial DUS followed by confirmatory CE-MRA best matches patient selection by arteriography. Single modality imaging for 50% to 69% ICA stenoses suggests reduced reliability resulting in more inappropriate operations.
  
  
  CONCLUSIONS
  DUS is the optimum screening tool due to its sensitivity and specificity, availability, and low cost. When CEA appears indicated, confirmatory imaging with CE-MRA is the most reliable and cost-effective method of investigation.
authors.affiliation: Leeds Vascular Institute, The General Infirmary at Leeds, Leeds, United Kingdom. michael.gough@yorksandhumber.nhs.uk
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gough
mesh_terms: D016893:Carotid Stenosis / Q000150:complications / Q000175:diagnosis* / Q000191:economics / Q000628:therapy; D003287:Contrast Media; D003362:Cost-Benefit Analysis; D003952:Diagnostic Imaging / Q000191:economics / Q000379:methods; D019317:Evidence-Based Medicine; D017048:Health Care Costs; D006801:Humans; D018810:Magnetic Resonance Angiography; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D018616:Ultrasonography, Doppler, Duplex
chemical_list: D003287:Contrast Media