Rita Gouveia Nunes1, Joseph V. Hajnal1, David J. Larkman1
1Robert Steiner MRI Unit, Imaging Sciences Department, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK
Continuously-Moving table allows efficient acquisition of whole-body images. Unfortunately, B0, gradient and B1 field imperfections result in data inconsistency leading to artifacts. Commonly, to reduce these, smaller excitation volumes are used and linear k-space traversal imposed, limiting the range of contrasts attainable. Polzin et al. developed a reconstruction method which incorporates distortion correction due to gradient non-linearities. We show that although this approach is reasonably accurate for linear schemes, its performance is poorer for segmented acquisitions. Improved reconstructions can be obtained for all schemes using the Generalised Image Reconstruction Accounting For Field Effects method, increasing design flexibility and scanning efficiency.
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