Objective: This study was performed to evaluate the feasibility of using MR angiography for following up patients who have undergone interventional therapy of the infrapopliteal vascular bed.
Subjects and methods: Fourteen patients with peripheral vascular disease underwent MR imaging before and after percutaneous transluminal angioplasty (PTA) using a two-dimensional time-of-flight technique (TR/TE, 33/3.9; section thickness, 2.9 mm). As the gold standard, selective digital subtraction angiography was obtained for all evaluated extremities before and after PTA. For data analysis, the distal peripheral arterial system was divided into 11 segments: the popliteal artery; the tibioperoneal trunk; and the proximal, mid, and distal portions of the three trifurcation vessels. Each segment was characterized as normal, mildly diseased, moderately diseased, severely diseased, or occluded.
Results: We found overall agreement between the two techniques in 110 segments (71%) and 123 segments (80%) on data obtained before and after PTA, respectively. Before PTA, our interpretation of MR angiograms overestimated 14 lesions (9%). After PTA, we overestimated five lesions (3%) on MR angiograms. We underestimated lesion severity in 30 cases (19%). The high incidence of agreement between the two techniques was reflected by the high Kendall's tau-beta values of .83 and .87 for data obtained before and after PTA, respectively.
Conclusion: The excellent depiction of the PTA-induced morphologic changes suggests great potential for the use of MR angiograms during interventional follow-up.