title: Diagnostic accuracy of intraarterial and i.v. MR angiography for the detection of stenoses of the infrainguinal arteries.
abstract: OBJECTIVE
  The objective of our study was to prospectively evaluate the diagnostic accuracy of intraarterial (i.a.) and i.v. MR angiography (MRA) of the infrainguinal arteries in comparison with the reference standard selective digital subtraction angiography (DSA).
  
  
  METHODS
  Twenty consecutive patients with symptomatic peripheral arterial occlusive disease (PAOD) underwent i.v. MRA and i.a. MRA of the infrainguinal arteries and DSA, which served as the reference standard. For i.v. MRA, 27 mL of gadodiamide was injected through a peripheral arm vein; for i.a. MRA, 30 mL of diluted contrast agent (5 mL of gadodiamide in 55 mL of 0.9% saline solution) was twice injected in the superficial femoral artery with a flow rate of 2.5 mL/s through a 5-French sheath that was placed on the occasion of DSA before vascular intervention. A 3D gradient-echo sequence was performed using a dedicated coil system on a 1.5-T MR scanner. Three independent blinded observers localized and quantitatively graded stenoses on i.v. MRA and i.a. MRA. The overall impression of image quality of i.v. MRA and i.a. MRA was documented using a 4-point scale (1, excellent; 4, poor). Interobserver agreement was calculated.
  
  
  RESULTS
  The mean sensitivity and mean specificity for the detection of stenoses >or= 50% of the upper leg arteries (i.e., superficial femoral artery and popliteal artery) were 85.5% and 83.3% for i.a. MRA and 82.2% and 86.7% for i.v. MRA, respectively. The mean sensitivity and mean specificity for the detection of stenoses >or= 50% of the lower leg arteries (i.e., proximal anterior tibial artery, tibiofibular trunk, proximal posterior tibial artery, and proximal peroneal artery) were 91.7% and 75.0% for i.a. MRA, respectively, and 87.5% each for i.v. MRA. the diagnostic quality of i.a. MRA images and i.v. MRA images was assessed as excellent or good.
  
  
  CONCLUSIONS
  i.a. MRA provides sensitivity and specificity for the detection of hemodynamically significant stenoses of the infrainguinal arteries comparable to i.v. MRA and therefore is a good diagnostic tool especially for MR-guided vascular interventions.
authors.affiliation: Department of Radiology, University Hospital of Regensburg, Franz-Josef-Strauss-Allee 11, Regensburg, Bavaria D-93053, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Poschenrieder
authors.forename: Okka W
authors.initials: OW
authors.lastname: Hamer
authors.forename: Thomas
authors.initials: T
authors.lastname: Herold
authors.forename: Thomas
authors.initials: T
authors.lastname: Schleicher
authors.forename: Ingitha
authors.initials: I
authors.lastname: Borisch
authors.forename: Stefan
authors.initials: S
authors.lastname: Feuerbach
authors.forename: Niels
authors.initials: N
authors.lastname: Zorger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity