Comparison of contrast-enhanced MR angiography to intraarterial digital subtraction angiography for evaluation of peripheral arterial occlusive disease: results of a phase III multicenter trial.

Objective: To evaluate the efficacy and safety of 0.1 mmol/kg gadodiamide administration for contrast-enhanced magnetic resonance angiography (CE-MRA) in detecting hemodynamically relevant main stenosis (ie, > or = 50% or occlusion) of aortoiliac arteries.

Methods: In a multicenter, phase 3, controlled study, patients with suspected or proven peripheral arterial occlusive disease (PAOD) underwent CE-MRA with administration of gadodiamide. Intraarterial digital subtraction angiography (IA-DSA) was used as the reference. The study was approved by all Institutional Review Boards or Institutional Ethic Committees prior to commencement of patient recruitment and written informed consent was obtained from all patients.

Results: Independent readers rated 25%-45% of CE-MRA images as excellent compared with 0.3%-6% of noncontrast MRA images. Mean imaging acquisition time for CE-MRA was <1 minute (0.7 +/- 1.9 minutes) versus 10 minutes (10.8 +/- 3.0) for noncontrast MRA. Sensitivity, specificity, and accuracy of CE-MRA were superior compared with those of noncontrast MRA in detecting significant arterial stenoses. Compared with IA-DSA, the sensitivity of CE-MRA ranged from 80%-88% and the specificity from 73% to 92% for the three blinded readers, at the patient level.

Conclusions: Diagnostic results with CE-MRA were superior and more consistent compared with noncontrast MRA for detecting hemodynamically relevant main stenoses in patients with suspected or proven PAOD and compared favorably with IA-DSA as a reference standard.