Figure 1

Reference, Ref and Velocity encoded, Vel magnitude and phase images with corresponding velocity maps of the popliteal artery at low and peak velocity at 50cm/s VENC with initial frequency offsets -40, 0, +40 Hz. Low velocity images show symmetric distortion of the artery on ref. and vel. magnitude images while the phase images show a positive phase slope with negative off-resonance and negative phase slope with positive off-resonance; and is similar between ref. and vel. images. Peak velocity shows similar distortions on the ref. magnitude and phase images as at low velocity. The vel. magnitude images show an implosion (I) and explosion (E) effect as the signal loss due to shear phase dispersion is increased and decreased respectively; the vel. phase images show the off-resonance induced phase adding destructively and constructively to the vel. induced phase resulting in varying velocity profiles across the artery in the VMs.