Abstract: Systems and methods for correction of eddy current induced distortions in diffusion MRI. Adjustment scans acquire images with diffusion encodings. A machine learned network computes spatial distortion maps. The spatial distortion maps are used to correct eddy current induced distortions is subsequent acquisitions.

Abstract: Systems and methods for correction of a magnetic field for an MRI procedure. Two reference acquisitions are acquired having different readout gradients, for example with reversed polarity. A machine learning network generates a displacement map from the two reference acquisitions. A spatial distortion map of the magnetic field is generated by the displacement map. The spatial distortion map of the magnetic field may be used for correction of the magnetic field or processing of further acquired images.

Abstract: Systems and methods for performing diffusion-weighted magnetic resonance imaging (“MRI”), including reconstructing and analyzing images, while preserving phase information that is traditionally discarded in such applications, are provided. For instance, background phase variations are eliminated, which enables complex-valued data analysis without the usual noise bias. As a result, the systems and methods described here provide an image reconstruction that enables true signal averaging, which increases signal-to-noise ratio (“SNR”) and allows higher contrast in diffusion model reconstructions without a magnitude bias.

Abstract: Systems and methods for controlling a magnetic resonance imaging (MRI) system to simultaneously excite multiple different slice locations. A multiband (MB) radio frequency (RF) pulse waveform is combined with an RF pulse waveform that results in periodic excitation of the slice locations, such as a power independent of a number of slices (PINS) RF pulse waveform. Before combination, the MB RF pulse waveform is preferably transformed to traverse the excitation k-space trajectory defined by a plurality of slice-encoding gradient blips. The combined RF pulse waveform is used to generate an RF excitation field generated while the plurality of slice-encoding gradient blips are played out. The portions of the combined RF pulse associated with the MB RF pulse are played out during the gradient blips, and the portions associated with the PINS RF pulse are played out between the gradient blips.

Abstract: Systems and methods for performing diffusion-weighted magnetic resonance imaging (“MRI”), including reconstructing and analyzing images, while preserving phase information that is traditionally discarded in such applications, are provided. For instance, background phase variations are eliminated, which enables complex-valued data analysis without the usual noise bias. As a result, the systems and methods described here provide an image reconstruction that enables true signal averaging, which increases signal-to-noise ratio (“SNR”) and allows higher contrast in diffusion model reconstructions without a magnitude bias.

Abstract: Systems and methods for controlling a magnetic resonance imaging (MRI) system to simultaneously excite multiple different slice locations. A multiband (MB) radio frequency (RF) pulse waveform is combined with an RF pulse waveform that results in periodic excitation of the slice locations, such as a power independent of a number of slices (PINS) RF pulse waveform. Before combination, the MB RF pulse waveform is preferably transformed to traverse the excitation k-space trajectory defined by a plurality of slice-encoding gradient blips. The combined RF pulse waveform is used to generate an RF excitation field generated while the plurality of slice-encoding gradient blips are played out. The portions of the combined RF pulse associated with the MB RF pulse are played out during the gradient blips, and the portions associated with the PINS RF pulse are played out between the gradient blips.