Abstract: Techniques are provided for imaging a subject. The method may comprise receiving an indication to image the subject using an magnetic resonance imaging (MRI) system, and in response to receiving the indication, with at least one controller: generating, using at least one RF coil, an initial MR data set for generating an initial image of the subject; determining, using the initial MR image, a difference in orientation between a current orientation of the subject in the initial MR image and a target orientation of the subject; determining, using the determined difference in orientation, an adjustment to a gradient pulse sequence for controlling at least one gradient coil; applying the determined adjustment to the gradient pulse sequence to obtain an adjusted gradient pulse sequence; generating an adjusted MR data set using the adjusted gradient pulse sequence; and generating a second MR image of the subject using the adjusted MR data set.

Abstract: An apparatus for controlling at least one gradient coil of a magnetic resonance imaging (MRI) system. The apparatus may include at least one computer hardware processor; and at least one computer-readable storage medium storing processor executable instructions that, when executed by the at least one computer hardware processor, cause the at least one computer hardware processor to perform a method. The method may include receiving information specifying at least one target pulse sequence; determining a corrected pulse sequence to control the at least one gradient coil based on the at least one target pulse sequence and a hysteresis model of induced magnetization in the MRI system caused by operation of the at least one gradient coil; and controlling, using the corrected gradient pulse sequence, the at least one gradient coil to generate one or more gradient pulses for imaging a patient.

Abstract: Techniques for removing artefacts, such as RF interference and/or noise, from magnetic resonance data. The techniques include: obtaining input magnetic resonance (MR) data using at least one radio-frequency (RF) coil of a magnetic resonance imaging (MRI) system; and generating an MR image from input MR data at least in part by using a neural network model to suppress at least one artefact in the input MR data.

Abstract: A magnetic resonance imaging (MRI) system and method for acquiring magnetic resonance (MR) images using a pulse sequence implementing driven equilibrium and quadratic phase cycling techniques is provided. The method includes, during a pulse repetition period of a pulse sequence and using a quadratic phase cycling scheme, applying a first RF pulse to deflect a net magnetization vector associated with the subject from a longitudinal plane into a transverse plane; after applying the first RF pulse, applying a first sequence of RF pulses each of which flips the net magnetization vector by approximately 180 degrees within the transverse plane; and after applying the first sequence of RF pulses, applying a second RF pulse to deflect the net magnetization vector from the transverse plane to the longitudinal plane.

Abstract: Techniques are provided for imaging a subject. A magnetic resonance imaging (MRI) system may use at least one RF coil to generate an initial MR data set for an initial image of the subject. The MRI system may use the initial MR image to determine a difference in orientation between a current orientation of the subject in the initial MR image and a target orientation of the subject. The MRI system may use the determined difference in orientation to determine an adjustment to a gradient pulse sequence for controlling at least one gradient coil. The MRI system may apply the determined adjustment to the gradient pulse sequence to obtain an adjusted gradient pulse sequence. The MRI system may generate an adjusted MR data set using the adjusted gradient pulse sequence, and a second MR image of the subject using the adjusted MR data set.

Abstract: Systems and methods are provided herein for determining whether to extend scanning performed by a magnetic resonance imaging (MRI) system. According to some embodiments, there is provided a method for imaging a subject using an MRI system, comprising: obtaining data for generating at least one magnetic resonance image of the subject by operating the MRI system in accordance with a first pulse sequence; prior to completing the obtaining the data in accordance with the first pulse sequence, determining to collect additional data to augment and/or replace at least some of the obtained data; determining a second pulse sequence to use for obtaining the additional data; and after completing the obtaining the data in accordance with the first pulse sequence, obtaining the additional data by operating the MRI system in accordance with the second pulse sequence.

Abstract: Techniques of prospectively compensating for motion of a subject being imaged by an MRI system, the MRI system comprising a plurality of magnetics components including at least one gradient coil and at least one radio-frequency (RF) coil, the techniques comprising: obtaining first spatial frequency data and second spatial frequency data by operating the MRI system in accordance with a pulse sequence, wherein the pulse sequence is associated with a sampling path that includes at least two non-contiguous portions each for sampling a central region of k-space; determining a transformation using a first image obtained using the first spatial frequency data and a second image obtained using the second spatial frequency data; correcting the pulse sequence using the determined transformation to obtain a corrected pulse sequence; and obtaining additional spatial frequency data in accordance with the corrected pulse sequence.

Abstract: Techniques for removing artefacts, such as RF interference and/or noise, from magnetic resonance data. The techniques include: obtaining input magnetic resonance (MR) data using at least one radio-frequency (RF) coil of a magnetic resonance imaging (MRI) system; and generating an MR image from input MR data at least in part by using a neural network model to suppress at least one artefact in the input MR data.

Abstract: Systems and methods are provided herein for determining whether to extend scanning performed by a magnetic resonance imaging (MRI) system. According to some embodiments, there is provided a method for imaging a subject using an MRI system, comprising: obtaining data for generating at least one magnetic resonance image of the subject by operating the MRI system in accordance with a first pulse sequence; prior to completing the obtaining the data in accordance with the first pulse sequence, determining to collect additional data to augment and/or replace at least some of the obtained data; determining a second pulse sequence to use for obtaining the additional data; and after completing the obtaining the data in accordance with the first pulse sequence, obtaining the additional data by operating the MRI system in accordance with the second pulse sequence.

Abstract: Techniques of prospectively compensating for motion of a subject being imaged by an MRI system, the MRI system comprising a plurality of magnetics components including at least one gradient coil and at least one radio-frequency (RF) coil, the techniques comprising: obtaining first spatial frequency data and second spatial frequency data by operating the MRI system in accordance with a pulse sequence, wherein the pulse sequence is associated with a sampling path that includes at least two non-contiguous portions each for sampling a central region of k-space; determining a transformation using a first image obtained using the first spatial frequency data and a second image obtained using the second spatial frequency data; correcting the pulse sequence using the determined transformation to obtain a corrected pulse sequence; and obtaining additional spatial frequency data in accordance with the corrected pulse sequence.

Abstract: Techniques for compensating for presence of eddy currents during the operation of a magnetic resonance imaging (MRI) system in accordance with a pulse sequence, the pulse sequence comprising a gradient waveform associated with a target gradient field. The techniques include: compensating for presence of eddy currents during operation of the MRI system at least in part by correcting the gradient waveform using a nonlinear function of a characteristic of the gradient waveform to obtain a corrected gradient waveform; and operating the MRI system in accordance with the corrected gradient waveform to generate the target gradient field.

Abstract: A magnetic resonance imaging (MRI) system and method for acquiring magnetic resonance (MR) images using a pulse sequence implementing driven equilibrium and quadratic phase cycling techniques is provided. The method includes, during a pulse repetition period of a pulse sequence and using a quadratic phase cycling scheme, applying a first RF pulse to deflect a net magnetization vector associated with the subject from a longitudinal plane into a transverse plane; after applying the first RF pulse, applying a first sequence of RF pulses each of which flips the net magnetization vector by approximately 180 degrees within the transverse plane; and after applying the first sequence of RF pulses, applying a second RF pulse to deflect the net magnetization vector from the transverse plane to the longitudinal plane.

Abstract: Techniques for generating magnetic resonance (MR) images of a subject from MR data obtained by a magnetic resonance imaging (MRI) system, the techniques include: obtaining input MR spatial frequency data obtained by imaging the subject using the MRI system; generating an MR image of the subject from the input MR spatial frequency data using a neural network model comprising: a pre-reconstruction neural network configured to process the input MR spatial frequency data; a reconstruction neural network configured to generate at least one initial image of the subject from output of the pre-reconstruction neural network; and a post-reconstruction neural network configured to generate the MR image of the subject from the at least one initial image of the subject.

Abstract: A magnetic resonance imaging (MRI) system and method for acquiring magnetic resonance (MR) images using a pulse sequence implementing driven equilibrium and quadratic phase cycling techniques is provided. The method includes, during a pulse repetition period of a pulse sequence and using a quadratic phase cycling scheme, applying a first RF pulse to deflect a net magnetization vector associated with the subject from a longitudinal plane into a transverse plane; after applying the first RF pulse, applying a first sequence of RF pulses each of which flips the net magnetization vector by approximately 180 degrees within the transverse plane; and after applying the first sequence of RF pulses, applying a second RF pulse to deflect the net magnetization vector from the transverse plane to the longitudinal plane.

Abstract: A magnetic resonance imaging (MRI) system, comprising: a magnetics system comprising: a B0 magnet configured to provide a B0 field for the MRI system; gradient coils configured to provide gradient fields for the MRI system; and at least one RF coil configured to detect magnetic resonance (MR) signals; and a controller configured to: control the magnetics system to acquire MR spatial frequency data using non-Cartesian sampling; and generate an MR image from the acquired MR spatial frequency data using a neural network model comprising one or more neural network blocks including a first neural network block, wherein the first neural network block is configured to perform data consistency processing using a non-uniform Fourier transformation.

Abstract: Techniques are provided for imaging a subject. The method may comprise receiving an indication to image the subject using an magnetic resonance imaging (MRI) system, and in response to receiving the indication, with at least one controller: generating, using at least one RF coil, an initial MR data set for generating an initial image of the subject; determining, using the initial MR image, a difference in orientation between a current orientation of the subject in the initial MR image and a target orientation of the subject; determining, using the determined difference in orientation, an adjustment to a gradient pulse sequence for controlling at least one gradient coil; applying the determined adjustment to the gradient pulse sequence to obtain an adjusted gradient pulse sequence; generating an adjusted MR data set using the adjusted gradient pulse sequence; and generating a second MR image of the subject using the adjusted MR data set.

Abstract: Systems and methods for generating a gradient waveform for use by a low-field MRI system to generate a gradient magnetic field are provided herein. The gradient waveform can be determined using first information indicative of the gradient waveform and second information indicative of hardware constraints of the low-field MRI system including a maximum voltage of the gradient power amplifier, a maximum slew rate of the gradient coil, a resistance of the gradient coil, and an inductance of the gradient coil. In some embodiments, the gradient waveform can be a trapezoidal gradient waveform determined to have a non-linear ramp-up portion and/or a non-linear ramp-down portion.

Abstract: Systems and methods are provided herein for determining whether to extend scanning performed by a magnetic resonance imaging (MRI) system. According to some embodiments, there is provided a method for imaging a subject using an MRI system, comprising: obtaining data for generating at least one magnetic resonance image of the subject by operating the MRI system in accordance with a first pulse sequence; prior to completing the obtaining the data in accordance with the first pulse sequence, determining to collect additional data to augment and/or replace at least some of the obtained data; determining a second pulse sequence to use for obtaining the additional data; and after completing the obtaining the data in accordance with the first pulse sequence, obtaining the additional data by operating the MRI system in accordance with the second pulse sequence.

Abstract: A magnetic resonance imaging (MRI) system, comprising: a magnetics system comprising: a B0 magnet configured to provide a B0 field for the MRI system; gradient coils configured to provide gradient fields for the MRI system; and at least one RF coil configured. to detect magnetic resonance (MR) signals; and a controller configured to: control the magnetics system to acquire MR spatial frequency data using non-Cartesian sampling; and generate an MR image from the acquired MR spatial frequency data using a neural network model comprising one or more neural network blocks including a first neural network block, wherein the first neural network block is configured to perform data consistency processing using a non-uniform Fourier transformation.

Abstract: Methods and apparatus for operating a low-field magnetic resonance imaging (MRI) system to perform diffusion weighted imaging, the low-field MRI system including a plurality of magnetics components including a B0 magnet configured to produce a low-field main magnetic field B0, at least one gradient coil configured to, when operated, provide spatial encoding of emitted magnetic resonance signals, and at least one radio frequency (RF) component configured to acquire, when operated, the emitted magnetic resonance signals. The method comprises controlling one or more of the plurality of magnetics components in accordance with at least one pulse sequence having a diffusion-weighted gradient encoding period followed by multiple echo periods during which magnetic resonance signals are produced and detected, wherein at least two of the multiple echo periods correspond to respective encoded echoes having an opposite gradient polarity.