Methods for producing magnetic resonance images with sub-millisecond temporal resolution

A method for producing a series of time-resolved magnetic resonance (MR) images comprising:

• encoding spatial information into a magnetic resonance imaging (MRI) signal by manipulating a phase of the MRI signal within an MRI system;
• generating and outputting a phase-encoded MRI signal over time by digitizing a plurality of time points in the MRI signal;
• using the MRI system, repeating the generating and outputting step for a plurality of phase-encoded signals, each phase-encoded signal in synchrony with a trigger and each phase-encoded signal incorporating a distinctive or identical phase-encoding value and producing a plurality of digitized time points;
• and
• reconstructing a series of time-resolved MR images, each image of the series of time-resolved MR images at one specific time point selected from the plurality of digitized time points for each phase-encoded signal, by utilizing phase-encoded data acquired from the output of the plurality of phase-encoded signals, each image in the series of time-resolved MR images corresponding to a specific time point in the cyclic event.

A system for reconstructing a magnetic resonance (MR) image of a cyclic event with high temporal resolution, the system comprising:

• a phase encoder configured to phase encode spatial information into a magnetic resonance imaging (MRI) signal to produce a phase-encoded MRI signal by manipulating a phase of the MRI signal;
• a data acquisition system that performs a data acquisition process that samples the phase-encoded MRI signal at N instants in time in each of M data acquisition windows to generate N matrices, each matrix comprising a phase-encoded raw data set that corresponds to a respective point in time on the MRI signal, where M and N are positive integers that are greater than or equal to two, each data acquisition window being synchronized to the cyclic event;
• and
• a processor configured to process the phase-encoded raw data set to produce a reconstructed MR image of the cyclic event.

A system for reconstructing a magnetic resonance (MR) image of a cyclic event with high temporal resolution, the system comprising:

• a phase encoder configured to phase encode spatial information into a magnetic resonance imaging (MRI) signal to produce a phase-encoded MRI signal by manipulating a phase of the MRI signal, the MRI signal comprising a train of echoes of one of a free-induction decay (FID) signal, a gradient-echo signal, a spin-echo signal and a stimulated echo signal;
• a data acquisition system that performs an echo-train-based data acquisition process that samples the train of echoes such that each echo in the train of echoes is positioned in a respective time-resolved two-dimensional (2-D) k-space matrix and such that all echoes of the train of echoes are spread across a series of the time-resolved 2-D k-space matrices, the echo-train-based data acquisition process being repeated with different phase-encoding values applied by the phase encoder to the MRI signal to produce the phase-encoded MRI signal until all of the time-resolved 2-D k-space matrices are adequately sampled;
• and
• a processor configured to process the series of 2-D k-space matrices to produce a reconstructed MR image of the cyclic event with a temporal resolution determined by an inter-echo spacing between two adjacent echoes of the train of echoes.