Patent ID: 9568573
Date: 2017-02-14
CPC Classifications: G01R

Claim:
1. A method for automated magnetic field shimming in a Magnetic Resonance (MR) imaging system, the method comprising: generating radio frequency (RF) excitation pulses in a volume of patient anatomy comprising a patient's heart to provide subsequent acquisition of associated RF echo data; generating slice select magnetic field gradients on a static magnetic field for phase encoding and readout RF data acquisition in the volume of patient anatomy; generating a plurality of shimming routines, each shimming routine comprising applying non-linear magnetic field gradients to the static magnetic field to modify the homogeneity of the static magnetic field; acquiring a plurality of maps of the static magnetic field, each of the plurality of maps being acquired between each shimming routine; determining, by a control processor, a base function for each of the plurality of shimming coils from: (i) intermediate magnitudes and directions of the static magnetic field produced by each of the plurality of shimming coils during each shimming routine; and (ii) intermediate currents supplied to each of the plurality of shimming coils during each shimming routine; and determining, by the control processor, updated magnitudes and directions of the static magnetic field produced by each of the plurality of shimming coils by expanding the determined base function for each of the plurality of shimming coils into low order polynomials.