Purpose: To compare contrast-enhanced moving-bed magnetic resonance angiography (MRA) with digital subtraction angiography (DSA) for the ability to provide adequate information on which to construct a therapeutic strategy in patients suffering from peripheral arterial occlusive disease (PAOD).
Methods: A prospective study was conducted involving 48 consecutive patients (25 men; mean age 65.7+/-10.2 years) with PAOD who underwent MRA and DSA of the peripheral arteries on 2 consecutive days. Every leg was divided into 3 anatomical regions (suprainguinal, femoropopliteal, calf), and the sensitivity and specificity for the detection of significant (>70%) lesions, as well as the interobserver variability, were calculated. The potential differences in the therapeutic strategy based on the results of both modalities were evaluated.
Results: The MRA and DSA studies in the 48 study patients produced 864 arterial segments for interpretation. The sensitivity of MRA for the detection of significant lesions was 94.7% for the suprainguinal, 89.5% for the femoropopliteal, and 91.3% for the calf arteries. Corresponding specificity was 98.1%, 96.2% and 93.4%, respectively. The interobserver correlation for the detection of significant lesions by MRA and DSA was excellent (kappa>0.8) for all 3 segments, with slightly superior values for MRA. MRA and DSA agreed in the grading of 821 (95.0%) segments. In 8 (16.7%) patients, MRA suggested an additional intervention, and in 3 (6.3%) patients, additional DSA was necessary for the final diagnosis.
Conclusions: The accuracy of MRA for the detection of significant lesions is comparable to DSA. Basing the therapeutic strategy solely on the results of MRA can reduce the number of DSAs by three quarters, but at the risk of incurring lesion overestimation in approximately 17%.