A New Eddy-current Compensation Method in MRI

Abstract

We present here a new eddy-current compensation method. A mathematical model of eddy-current field is introduced to calculate first order eddy-current distorted non-uniform sampling trajectory in k-space. Based on the computed k-space trajectory, compensated image is reconstructed using the gridding method. In addition, the model of eddy-current field can also be used to calculate zero order eddy-current induced additional phase to correct the phase of MRI signal before gridding reconstruction, as long as such phase correction is able to further improve qualities of reconstructed image. Initial experiment on a 0.3T permanent MRI system demonstrates that the proposed method is able to reconstruct FSE (fast spin-echo) images of similar qualities as those produced by conventional gradient pre-emphasis method.doi:10.2529/PIERS061006031452