title: Magnetic resonance imaging in peripheral arterial disease: reproducibility of the assessment of morphological and functional vascular status.
abstract: OBJECTIVE
  The aim of the current study was to test the reproducibility of different quantitative magnetic resonance imaging (MRI) methods to assess the morphologic and functional peripheral vascular status and vascular adaptations over time in patients with peripheral arterial disease (PAD).
  
  
  METHODS
  Ten patients with proven PAD (intermittent claudication) and arterial collateral formation within the upper leg and 10 healthy volunteers were included. All subjects underwent 2 identical MR examinations of the lower extremities on a clinical 1.5-T MR system, with a time interval of at least 3 days. The MR protocol consisted of 3D contrast-enhanced MR angiography to quantify the number of arteries and artery diameters of the upper leg, 2D cine MR phase contrast angiography flow measurements in the popliteal artery, dynamic contrast-enhanced (DCE) perfusion imaging to determine the influx constant and area under the curve, and dynamic blood oxygen level-dependent (BOLD) imaging in calf muscle to measure maximal relative T2* changes and time-to-peak. Data were analyzed by 2 independent MRI readers. Interscan and inter-reader reproducibility were determined as outcome measures and expressed as the coefficient of variation (CV).
  
  
  RESULTS
  Quantification of the number of arteries, artery diameter, and blood flow proved highly reproducible in patients (CV = 2.6%, 4.5%, and 15.8% at interscan level and 9.0%, 8.2%, and 7.0% at interreader level, respectively). Reproducibility of DCE and BOLD MRI was poor in patients with a CV up to 50.9%.
  
  
  CONCLUSIONS
  Quantification of the morphologic vascular status by contrast-enhanced MR angiography, as well as phase contrast angiography MRI to assess macrovascular blood flow proved highly reproducible in both PAD patients and healthy volunteers and might therefore be helpful in studying the development of collateral arteries in PAD patients and in unraveling the mechanisms underlying this process. Functional assessment of the microvascular status using DCE and BOLD, MRI did not prove reproducible at 1.5 T and is therefore currently not suitable for (clinical) application in PAD.
authors.affiliation: Department of Radiology, Maastricht University Medical Center (MUMC), Maastricht, The Netherlands.
authors.forename: Bas
authors.initials: B
authors.lastname: Versluis
authors.forename: Walter H
authors.initials: WH
authors.lastname: Backes
authors.forename: Marcelle G A
authors.initials: MG
authors.lastname: van Eupen
authors.forename: Karolien
authors.initials: K
authors.lastname: Jaspers
authors.forename: Patty J
authors.initials: PJ
authors.lastname: Nelemans
authors.forename: Ellen V
authors.initials: EV
authors.lastname: Rouwet
authors.forename: Joep A W
authors.initials: JA
authors.lastname: Teijink
authors.forename: Willem P Th M
authors.initials: WP
authors.lastname: Mali
authors.forename: Geert-Willem
authors.initials: GW
authors.lastname: Schurink
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Wildberger
authors.forename: Tim
authors.initials: T
authors.lastname: Leiner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D016022:Case-Control Studies; D003097:Collateral Circulation; D016001:Confidence Intervals; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006304:Health Status; D006305:Health Status Indicators; D006439:Hemodynamics; D006801:Humans; D007383:Intermittent Claudication / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D058729:Peripheral Arterial Disease / Q000175:diagnosis* / Q000473:pathology; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA