Magnetresonanzphasenkontrastgeschwindigkeitsmessungen als noninvasive Nachbeobachtungsmaßnahme nach perkutaner transluminaler Angioplastie

Background: The aim of this study was to evaluate magnetic resonance phase contrast velocimetry (MRVL) as a non-invasive follow up tool to assess restenosis after percutaneous transluminal angioplasty (PTA). Patients and methods: We prospectively investigated 51 consecutive patients who underwent PTA of the femoropopliteal region. MRVL was conducted prior, one day, six weeks, twelve weeks and 24 weeks after PTA using a circular polarized extremity coil and a gradient echo sequence (TR/TE 600/6 ms, flip angle 30°, slice thickness 10 mm). Hemodynamic data, derived from the MR phase contrast sequence, allowed to calculate the degree of area stenosis of the lesion treated with PTA. These data were correlated with clinical hemodynamic parameters (ankle-brachial index and walking distance). Results: The mean grade of area stenosis was 69% ± 27% before PTA, 30% ± 20% one day, 29% ± 23% six weeks, 39% ± 17% twelve weeks and 42% ± 18% 24 weeks after PTA and correlated well with clinical data and the post angioplasty clinical course of the patients. Conclusions: Follow up measurements using MRVL are suitable to assess restenosis after PTA and allow quantifying the grade of recurrent stenosis as well as the hemodynamic consequences.