FIGURE 1.

MaxGIRF reconstruction flowchart. A, Computation of concomitant field model: Gradient waveforms in the logical coordinate system are first transformed into the physical coordinate system. Distorted gradients in the physical coordinate system are estimated by gradient impulse response functions (GIRFs). Analytic expressions of concomitant fields derived from the coil geometry, presumed gradient nonlinearity, and GIRF‐predicted gradients, are calculated for each spatial position in the physical coordinate system. B, Encoding model: The MaxGIRF encoding model is an extension of the SENSE model that additionally includes phase terms due to static off‐resonance and concomitant fields. The phase evolution per voxel is represented as the sum of phase contributions from static off‐resonance (red) and spatial basis functions (blue) that include both linear gradients and concomitant field terms