Analysis of flow and wall shear stress in the peroneal veins under external compression based on real-time MR images

Scan position of the subject.

Parameters of stocking size selection. (D) Length from bend of knee to bottom of heel and (C) calf circumference.

MR image of an uncompressed calf. ATV: anterior tibial vein; LPV/MPV: lateral/medial peroneal veins; LPTV/MPTV: lateral/medial posterior tibial veins.

Volumetric flow rate waveforms derived from MR flow mapping before (dashed lines) and after (continuous lines) compression.

Comparison of sample representative waveforms (continuous lines) and the MRI flow data (dashed lines). Data are taken from the medial peroneal vein in subject 1, before (top) and after (bottom) compression induced by the static compression stocking.

Time-averaged wall shear stress distribution in the MPV before and after compression viewed from posterior and lateral aspect.

Time-averaged wall shear stress distribution in the MPV before and after compression viewed from posterior and lateral aspect.

Axial variation of the ratio of cross-sectional mean velocity after and before compression (dashed lines), compared with the axial variation of the ratio of circumferentially averaged TAWSS after and before compression (continuous lines).

Variation of cross-sectional mean velocity (solid line) with time before (top) and after compression (bottom), compared with the corresponding WSS variation (dash line).

Anatomical MR images at different time points of the diaphragmatic controlled breathing cycle generated by using the real-time phase contrast velocity mapping sequence without compression stocking. MPV: medial peroneal vein.

Anatomical MR images at different time points of the diaphragmatic controlled breathing cycle generated by using the real-time phase contrast velocity mapping sequence with compression stocking. MPV: medial peroneal vein.

Measured blood flow waveforms in the medial peroneal veins of 2 subjects before (dashed lines) and after (continuous lines) compression. In both cases, an increase in the mean velocity and reduction in the waveform pulsatility were observed after compression.