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.

Methods, computing devices, and MRI systems that reduce artifacts produced by Maxwell gradient terms in TSE imaging using non-rectilinear trajectories are disclosed. With this technology, a RF excitation pulse is generated to produce transverse magnetization that generates a NMR signal and a series of RF refocusing pulses to produce a corresponding series of NMR spin-echo signals. An original encoding gradient waveform comprising a non-rectilinear trajectory is modified by adjusting a portion of the original encoding gradient waveform or introducing a zero zeroth-moment waveform segment at end(s) of the original encoding gradient waveform. During an interval adjacent to each of the series of RF refocusing pulses a first gradient pulse is generated. At least one of the first gradient pulses is generated according to the modified gradient waveform. An image is constructed from generated digitized samples of the NMR spin-echo signals obtained.

A method for actuating a magnetic resonance device according to an MR control sequence, wherein the MR control sequence includes a bipolar gradient pulse between an excitation pulse and a first refocusing pulse, and the bipolar gradient pulse induces a defined Maxwell phase and generates a dephasing gradient moment for a readout gradient.

A method for 3D oscillating-gradient prepared gradient spin-echo imaging and a device. The imaging method comprises the following steps: first, using a global saturation module to destroy previous residual transverse magnetization; second, embedding a pair of trapezoidal cosine oscillating gradients into a 90°.sub.x-180°.sub.y-90°.sub.−x radiofrequency pulse by a diffusion encoding module, to separate diffusion encoding from signal acquisition; then, using a fat saturation module to suppress a fat signal; finally, acquiring a signal by means of gradient spin-echo readout, and correcting phase errors among multiple excitations by multiplexed sensitivity-encoding reconstruction. Compared with a 2D plane echo-based oscillating gradient diffusion sequence used on a 3T clinical system, a 3D oscillating-gradient prepared gradient spin-echo sequence effectively reduces the imaging time, improves the signal to noise ratio, and is beneficial to clinical transformation of time-dependent diffusion MRI technology

In a method for MRI where k-space describing spatial frequencies in an acquisition volume (AV) is scanned, a first measured data acquisition is performed in the AV with a first gradient field strength of a gradient field, including irradiating a RF pulse into the AV and acquiring a first series of measured values spaced apart temporally, a second measured data acquisition is performed with a second, different gradient field strength, including irradiating a RF pulse into the AV and acquiring a second series of measured values spaced apart temporally. With the first measured data acquisition, the first measured values for a respective response signal are acquired at a first time interval from one another and with the second measured data acquisition, the second measured values for a respective response signal are acquired at a second, different time interval from one another.

In a method and system for the generation of measurement data required k-space is read out in the readout direction in k-space rows such that at least a first k-space row of the k-space rows does not cover the k-space to be read out in the readout direction in full and at least a second k-space row of the k-space rows covers the k-space to be read out in locations in the readout direction at which the first k-space row does not cover the k-space to be read out. Measurement data that is missing in the k-space is completed in this way on the basis of recorded echo signals stored as measurement data.

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.

The present disclosure relates to systems and methods for magnetic resonance imaging. The method may include obtaining primary imaging data associated with a region of interest (ROI) of a subject and obtaining secondary data associated with the ROI. The method may also include determining secondary imaging data based on the secondary data by using a trained model. The method may further include reconstructing a magnetic resonance image based on the primary imaging data and the secondary imaging data.

In one embodiment, an MRI apparatus includes: a scanner equipped with at least a static magnetic field magnet, a gradient coil, and an RF coil configured to apply RF pulses to an object and receive magnetic resonance signals from the object; and processing circuitry configured to set a pulse sequence in which refocusing pulses are sequentially applied subsequent to application of one excitation pulse and a predetermined number of magnetic resonance signals are acquired in each period between adjacent two refocusing pulses by using a water/fat separation method, such that the magnetic resonance signals are different in echo time TE for each of the plurality of refocusing pulses, cause the scanner to acquire the magnetic resonance signals under the pulse sequence, and generate a computed image from the magnetic resonance signals, the computed image being a magnetic resonance image of the object obtained by computation.

In a method and system, a reference dataset is recorded using a reference scan based on a GRE or RA RT sequence. A correction dataset is also recorded using a phase correction scan based on a non-phase-encoding EPI sequence. A measurement dataset is recorded using an SMS sequence. Slice-specific GRAPPA kernels are determined from the reference dataset and magnetic resonance images are created by a slice GRAPPA method. Data of the measurement dataset belonging to different slices is separated from one another using the slice-specific GRAPPA kernels and N/2 ghost artifacts are corrected using the correction dataset.