title: Intraarterial gadolinium-enhanced MR angiography in humans for the detection of infrainguinal arterial stenoses before and after percutaneous angioplasty.
abstract: OBJECTIVE
  The objectives of this study were to show the feasibility of intraarterial MR angiography of the infrainguinal arteries and to compare the accuracy of intraarterial MR angiography with selective intraarterial digital subtraction angiography for the detection of stenoses before and after percutaneous balloon angioplasty.
  
  
  METHODS
  Fifteen patients underwent digital subtraction angiography and intraarterial MR angiography before and after balloon angioplasty. For intraarterial MR angiography, 30 mL of diluted contrast agent (5 mL of gadodiamide diluted in 55 mL of 0.9% saline solution) was injected through a sheath in the superficial femoral artery using a flow rate of 2.5 mL/sec. A 3D gradient-echo sequence was performed. Four independent blinded observers assessed differences in the quantitative measurement of stenoses and localization of lesions between digital subtraction angiography and intraarterial MR angiography. The overall impression of the intraarterial MR angiography images was documented on a 4-point scale (1 = excellent, 4 = poor). Interobserver variability was calculated.
  
  
  RESULTS
  Intraarterial MR angiography from the upper leg to the trifurcation was feasible in all 30 examinations with a mean overall impression of all segments of 1.3 (SD, 0.68). For the detection of significant stenoses (> or = 50% stenosis), the overall sensitivity and specificity for the femoropopliteal and crural vessels were 92.4% and 91.7% and 91.9% and 87.8%, respectively. For the complete leg, sensitivity and specificity were 92.2% and 88.6%, respectively. Interobserver variability for intraarterial MR angiography of the crural vessels exceeded that of the femoropopliteal arteries.
  
  
  CONCLUSIONS
  Intraarterial MR angiography of the infrainguinal arteries is feasible in humans using injections of diluted contrast agent at concentrations as low as 8%. It has a high sensitivity for detecting stenoses and an acceptable interobserver variability.
authors.affiliation: Department of Radiology, University of Regensburg, Klinikum, Franz Josef Strauss Allee 11, Regensburg 93042, Germany.
authors.forename: Niels
authors.initials: N
authors.lastname: Zorger
authors.forename: Markus
authors.initials: M
authors.lastname: Volk
authors.forename: Okka W
authors.initials: OW
authors.lastname: Hamer
authors.forename: Markus
authors.initials: M
authors.lastname: Lenhart
authors.forename: Johannes
authors.initials: J
authors.lastname: Seitz
authors.forename: Bernhard
authors.initials: B
authors.lastname: Butz
authors.forename: Christian
authors.initials: C
authors.lastname: Paetzel
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D000800:Angioplasty, Balloon; D001157:Arterial Occlusive Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000628:therapy; D001161:Arteriosclerosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000628:therapy; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007264:Inguinal Canal / Q000098:blood supply*; D007866:Leg / Q000098:blood supply*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA