FIGURE 9.

Comparison of reconstruction methods compensating a different number of concomitant field terms. Midsagittal spiral imaging of a healthy volunteer at isocenter at 0.55 T. First column: NUFFT. Second column: King's method without static off‐resonance correction. Third column: Conjugate phase reconstruction–based MaxGIRF using only lowest‐order terms in the concomitant fields. Fourth column: Conjugate phase reconstruction–based MaxGIRF using entire terms in the concomitant fields (full order). Fifth column: Conjugate gradient (CG)–based MaxGIRF using full‐order terms (absolute difference images between reconstructions at the bottom). The GIRF‐predicted gradients were used in all reconstructions. Static off‐resonance correction was not performed, to isolate the difference due to concomitant field correction. The spiral trajectory was designed for 224 × 224 mm² FOV and reconstructed at twice the FOV with the same spatial resolution, which causes the aliasing at the back of the neck