Saikat Sengupta1,2, Brian E. Welch, 1,3,
Adam Anderson1,4, John Gore1,4, Malcolm J. Avison1,4
We
present a novel method of eddy current compensation for higher order shim
induced eddy currents in a multislice Dynamic Shimming (DS) experiment,
without the use of extra hardware. This method is based on an assumption of
reaching an eddy field steady state during a fast field echo (FFE)
acquisition. Using calibration scans, we characterize eddy field interactions
between any two shims in terms of correction factor vectors that remain
invariant with sample and shim values, for a given time between shim switches.
These factors are then used to prospectively compensate for expected eddy
fields in any FFE DS experiment.
Keywords