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.

The present disclosure relates to a system and method for MRI with respect to vessels and bleedings. The method may include exciting a region of interest by applying an RF pulse, wherein the region of interest includes a vessel region and a bleeding region. The method may further include acquiring a plurality of echo signals related to the region of interest. The method may further include generating one or more magnitude images based on the plurality of echo signals, generating a first image with respect to the vessel region based on the one or more magnitude images, generating one or more phase images based on the plurality of echo signals, and generating a second image with respect to a distribution of susceptibility of the bleeding region based on the one or more phase images.

A method for measuring water exchange across the blood-brain barrier includes acquiring diffusion weighted (DW) arterial spin labeling (ASL) magnetic resonance imaging (Mill) signals. The method further includes determining optimal parameters to separate labeled water in capillary and brain tissue compartments. The method further includes estimating water exchange rate across the blood-brain barrier based on the DW ASL MRI signals and the optimal parameters, using a total generalized variation (TGV) regularized single-pass approximation (SPA) modeling algorithm.

A plurality of subject parameter maps are acquired at high speed. In addition to using an imaging sequence for generating both a gradient echo and a spin echo in a single imaging sequence, one or more parameters such as the longitudinal relaxation time T1 and the apparent transverse relaxation time T2* are calculated using the gradient echo and another parameter such as true transverse relaxation time T2 is calculated using the spin echo. When a value of one parameter is calculated, a value of the parameter calculated at the time of calculating the other parameter can be used.

A method for generating an image data set of an image area located in a measurement volume of a magnetic resonance system comprising a gradient system and an RF transmission/reception system, comprises the following method steps: reading out k-space corresponding to the imaging area, by: (a) activating a frequency encoding gradient in a predetermined spatial direction and with a predetermined strength G.sub.0 by means of said gradient system, (b) after the activated frequency encoding gradient achieves its strength G.sub.0, radiating a non-slice-selective RF excitation pulse by means of said RF transmission/reception system, (c) after a transmit-receive switch time t.sub.TR following the radiated excitation pulse, acquiring FID signals with said RF transmission/reception system and storing said FID signals as raw data points in k-space along a radial k-space trajectory that is predetermined by the direction and strength G.sub.0 of the frequency encoding gradient, (d) repeating (a) through (c) with respectively different frequency encoding gradient directions in each repetition until k-space corresponding to the image area is read out in an outer region of k-space along radial k-space trajectories, said radial k-space trajectories each having a radially innermost limit k.sub.gap which depends on said switch time t.sub.TR, (e) reading out a remainder of k-space that corresponds to the imaging area, said remainder being an inner region of k-space not being filled by said first region and including at least a center of k-space, in a read out procedure that is different from (a) through (d), and storing all data points read out in (d) and (e); and reconstructing image data from the read out data points ink-space by implementing a reconstruction algorithm; In order to constrain image fidelity and optimize scan duration under given circumstances, the inner k-space region is subdivided into a core region and at least one radially adjacent shell region.

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.

Magnetic resonance imaging (MRI) data are corrected from corruptions due to physiological changes using a self-navigated phase correction technique. Unlike motion correction techniques, the effects of physiological changes (e.g., breathing and respiration) are corrected by making the MRI data self-consistent relative to an absolute uncorrupted phase reference. This phase correction information can be extracted from the acquisition itself, thereby eliminating the need for a separate navigator scan, and establishing an accelerated acquisition. This absolute reference can be computed in a data segmented space, and the subsequent data can be corrected relative to this absolute reference with low-resolution phases.

Systems and methods include conversion of a first frame of k-space data acquired using a first initial readout polarity to first hybrid (k.sub.x, y)-space data, conversion of a second frame of k-space data acquired using a second initial readout polarity to second hybrid (k.sub.x, y)-space data, determination of a relationship between phase difference and y-position based on phase differences between a plurality of pixels located at k.sub.x=a of first hybrid (k.sub.x, y)-space data and a plurality of pixels at k.sub.x=b of second hybrid (k.sub.x, y)-space data, where a and b are constants, modification of the second hybrid (k.sub.x, y)-space data based on the relationship, conversion of the modified second hybrid (k.sub.x, y)-space data to a modified second frame of k-space data, generation of two single-polarity readout k-space frames based on the first frame of k-space data and the modified second frame of k-space data, and correction of a third frame of EPI image data based on the two single-readout polarity k-space frames.

The invention relates to a method of Dixon-type MR imaging. The method comprises the steps of:subjecting the object (10) to a first imaging sequence (31) comprising a series of refocusing RF pulses, wherein a single echo signal is generated in each time interval between two consecutive refocusing RF pulses,acquiring the echo signals from the object (10) at a first receive bandwidth using unipolar readout magnetic field gradients,subjecting the object (10) to a second imaging sequence (32), which comprises a series of refocusing RF pulses, wherein a pair of echo signals is generated in each time interval between two consecutive refocusing RF pulses,acquiring the pairs of echo signals from the object (10) at a second receive bandwidth using bipolar readout magnetic field gradients, wherein the second receive bandwidth is higher than the first receive bandwidth, andreconstructing a MR image from the acquired echo signals, whereby signal contributions from water protons and fat protons are separated. Moreover the invention relates to a MR device (1) and to a computer program to be run on a MR device (1).

According to one embodiment, a data processing apparatus includes processing circuitry. The processing circuitry acquires input data relating to a processing target including a plurality of data segments corresponding respectively to a plurality of imaging contrasts determined by a first pulse sequence. The processing circuitry generates output data relating to the processing target by applying a trained model to input data relating to the processing target. The processing circuitry outputs output data relating to the processing target.