Evaluation of background phase errors from eddy currents and mechanical oscillations in phase contrast magnetic resonance imaging

Motivation: Background phase errors in PC-MRI include eddy currents and mechanical oscillations. Relative contributions over a wide range of velocity encoding gradients (VENCs) remain underexplored. Goal(s): To evaluate background phase errors across clinically relevant VENCs, characterizing the impact of eddy currents and mechanical oscillations. Approach: Waveforms with a range of VENCs were generated, and the gradient impulse response function was used to predict phase errors as a sum of eddy current and mechanical oscillation effects. Phantom experiments across different VENCs were conducted. Results: Eddy current effects dominated lower VENCs. Between approximately 52 and 92 cm/s the phase error was largely oscillatory. Impact: The necessary correction for background phase errors depends on the VENCs, which explains why errors are protocol dependent.