Comparison of magnetic resonance angiography and contrast arteriography in peripheral arterial stenosis

Magnetic resonance angiography (MRA) has recently been shown to be more sensitive than contrast arteriography in the detection of patent distal runoff vessels. This study compares MRA and contrast arteriography in evaluating the severity of stenotic lesions in peripheral arteries, which has not been previously investigated. Forty-eight arterial stenoses (19 patients) were identified, from the distal aorta through the crural vessels. Contrast arteriograms (anterioposterior projection) and MRA axial images were used to measure stenoses. Interobserver agreement of arteriogram readings was excellent (average weighted κ=0.87). Measurements of degree of stenosis as evaluated by MRA and contrast arteriography were analyzed by linear regression and Spearman rank correlation, which showed a high degree of correlation between the two diagnostic modalities (r=0.83, p<0.001; r_s=0.84, p<0.001). These observations suggest that MRA is accurate in the evaluation of peripheral arterial stenosis when compared with the "gold standard" contrast arteriogram. In addition, MRA cross-sectional images provide information beyond that of conventional arteriography, showing details of plaque eccentricity and vessel wall characteristics. In the future, MRA may supplant diagnostic contrast arteriography for many patients.