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Abstract #4246

Fast Monotonic Convergent Optimal Control Algorithm for 2D RF Pulses Mitigating B0 and B1 Inhomogeneities

Mads Sloth Vinding1, Ivan I. Maximov2, Zdenek Tosner3, Niels Christian Nielsen1

1iNANO, inSPIN, Aarhus University, Aarhus, Jutland, Denmark; 2Institute of Neuroscience and Medicine 4, Juelich, Germany; 3Charles University, Prague, Czech Republic

We present numerical simulations of B0 and B1 inhomogeneity compensation for 2D RF pulses derived using a monotonical convergent optimal control algorithm. The algorithm has proven rather fast compared to other gradient-based methods which is paramount for in vivo applications and it is quite robust with respect to the initial guess. Following up on our recent published experimental validation we here show that the algorithm in this study is capable of alleviating B0 inhomogeneity in a fictive B0 map of a 250 Hz linewidth, as well as B1 inhomogeneity of at least 9% inside the ROI.

Keywords

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