title: Intraarterial MR angiography and DSA in patients with peripheral arterial occlusive disease: prospective comparison.
abstract: OBJECTIVE
  To prospectively evaluate the accuracy of intraarterial magnetic resonance (MR) angiography in the depiction of significant stenoses and occlusions, with intraarterial digital subtraction angiography (DSA) serving as the reference standard.
  
  
  METHODS
  Approval of the local ethics committee and informed consent were obtained. Twenty patients (11 men; nine women; age range, 48-86 years; mean age, 69.5 years+/-11.2 [standard deviation]) with symptomatic peripheral arterial occlusive disease (PAOD) were prospectively enrolled. After percutaneous transluminal angioplasty (PTA), intraarterial MR angiography was performed in the thigh and the calf with a 1.5-T MR imager in two consecutive runs. Intraarterial MR angiography was performed with a low-dose injection protocol (ie, two 20-mL injections of a 50-mmol gadolinium-based contrast agent). Moderate stenoses (luminal narrowing<or=50%), significant stenoses (luminal narrowing 51%-99%), and occlusions (luminal narrowing of 100%) were identified on MR angiograms, which were compared with intraarterial DSA images. Intraarterial MR angiograms were analyzed for imaging artifacts. Sensitivity, specificity, accuracy, and positive and negative predictive values of intraarterial MR angiography with intraarterial DSA were determined for characterization of significant stenoses (>50%) or vessel occlusions; 95% confidence intervals (CIs) were calculated for sensitivity and specificity.
  
  
  RESULTS
  Intraarterial DSA revealed 78 moderate stenoses, 57 significant stenoses, and 28 occlusions. Sensitivity, specificity, and accuracy of intraarterial MR angiography in the characterization of significant stenoses or occlusions were 92% (95% CI: 72%, 99%), 94% (95% CI: 82%, 98%), and 93%, respectively, in femoropopliteal arteries and 93% (95% CI: 83%, 98%), 71% (95% CI: 51%, 86%), and 86%, respectively, in infrapopliteal arteries. The main artifact observed with intraarterial MR angiography was venous contamination (12%).
  
  
  CONCLUSIONS
  Intraarterial MR angiography is an accurate method used to depict significant stenoses and occlusions in lower extremity arteries with a low-dose injection protocol.
authors.affiliation: Department of Radiology, University Hospital of Basel, Petersgraben 4, 4031 Basel, Switzerland. rhuegli@uhbs.ch
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Huegli
authors.forename: Markus
authors.initials: M
authors.lastname: Aschwanden
authors.forename: Georg
authors.initials: G
authors.lastname: Bongartz
authors.forename: Kurt
authors.initials: K
authors.lastname: Jaeger
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Heidecker
authors.forename: Christoph
authors.initials: C
authors.lastname: Thalhammer
authors.forename: Anja-Carina
authors.initials: AC
authors.lastname: Schulte
authors.forename: Claus
authors.initials: C
authors.lastname: Hashagen
authors.forename: Augustinus L
authors.initials: AL
authors.lastname: Jacob
authors.forename: Deniz
authors.initials: D
authors.lastname: Bilecen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D000800:Angioplasty, Balloon; D001157:Arterial Occlusive Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D016477:Artifacts; D003251:Constriction, Pathologic / Q000175:diagnosis / Q000000981:diagnostic imaging; D003287:Contrast Media; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007866:Leg / Q000098:blood supply; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011150:Popliteal Artery / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013848:Thigh / Q000098:blood supply
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA