The present disclosure is related to systems and methods for magnetic resonance imaging (MRI). The method includes obtaining a plurality of target sets of k-space data by filling target MR signals acquired by a plurality of coils of an MRI device into k-space along a corkscrew trajectory. The method includes obtaining a coil sensitivity of each of the plurality of coils. The method includes obtaining a point spread function corresponding to the corkscrew trajectory. The method includes generating a target image based on an objective function.

A method may include obtaining a plurality of imaging signals collected by applying a wave encoding gradient to a region of interest (ROI) of a subject. The method may also include obtaining a plurality of auxiliary signals associated with the ROI. The method may also include obtaining a point spread function corresponding to the wave encoding gradient. The method may also include determining, based on the plurality of auxiliary signals, temporal information relating to at least one temporal dimension of the ROI. The method may also include determining, based on the plurality of auxiliary signals, the plurality of imaging signals, and the point spread function, spatial information relating to at least one spatial dimension of the ROI. The method may also include generating at least one target image of the ROI based on the temporal information and the spatial information.

A device for locating target points on a magnetic resonance image of the brain of a subject includes a trained neural network configured to receive as input a 3D MR image of the brain of a subject, and to output the location, on the image, of at least one determined brain target point. The neural network includes a plurality of processing stages. Each processing stage processes an image at a respective resolution, and the processing stage of lowest resolution outputs an estimate of the location of each target point. Each other processing stage is configured to receive, from a lower resolution processing stage, an estimate of the locations of the target points, crop the input image to a smaller region surrounding each estimated target point, determine an updated estimate of the location of each target point, and provide the updated estimation to the processing stage of the next higher resolution.

Disclosed is a method for generating a time-dependent magnetic field gradient in diffusion weighted magnetic resonance imaging G(t)=[G.sub.x(t)G.sub.y(t)G.sub.z(t)].sup.T, which is asymmetric in time with respect to a refocusing pulse, by meeting one or more of the requirements: A=∫.sub.0.sup.TEh(t)G(t)G(t).sup.Tdt is zero, where TE is an echo time and h(t) is a function of time which is positive during an interval prior to the refocusing pulse and negative during a time interval after the refocusing pulse); minimize A or m=(Tr[AA]).sup.1/2 where A=∫.sub.P1G(t)G(t).sup.Tdt−∫.sub.P2G(t)G(t).sup.Tdt where P1 and P2 represent time intervals prior to and subsequent to the refocusing pulse; m is smaller than a threshold value. an attenuation factor ${\mathrm{AF}}_p=\exp \left(-\frac{t}{T2*}\right)$
due to T2* relaxation is one. Signal attenuation due to concomitant field gradients, regardless of the shape or orientation of the diffusion encoding b-tensor and the location of signal is hereby minimized.

The present invention is to acquire a multiphase image while avoiding extension of imaging time and excluding an influence of displacement of an image of each multiphase due to a motion. A method for collecting measurement data is to repeat sampling such that low-frequency data and high-frequency data have different densities. At this time, a sampling interval is set shorter than a motion cycle. Motion information is acquired in parallel with imaging, and measurement data obtained in time series is divided into a plurality of time phases based on the motion information so as to obtain a multiphase image. Displacement correction between multiphase images is performed, and then the multiphase images are integrated. Alternatively, measurement data after the displacement correction is used to generate a time-series image.

Some embodiments of the present disclosure disclose systems and methods for robust magnetic resonance image reconstruction that can model for all or nearly all components in the magnetic resonance imaging system, that possess compressibility features to speed up reconstructions, and that can be optimized such that the reconstruction can be performed within a short period of time.

A medical image diagnosis apparatus according to an embodiment includes processing circuitry. The processing circuitry is configured to derive a subject-specific regression model that indicates a relationship among a cardiac cycle, systole, and diastole of the subject. The processing circuitry is configured to derive timing of a data acquisition in a synchronization imaging performed in synchronization with heartbeats of the heart of the subject, by using the derived regression model and electrocardiographic information of the subject obtained during an image taking process. The processing circuitry is configured to control the synchronization imaging so that the data acquisition is performed with the derived timing.

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 one embodiment, a magnetic resonance imaging apparatus includes: a scanner that includes a static magnetic field magnet configured to generate a static magnetic field, a gradient coil configured to generate a gradient magnetic field, and a WB (Whole Body) coil configured to apply an RF pulse to an object; and processing circuitry. The processing circuitry is configured to: set (i) a pulse sequence in which a sequence element is repeated, the sequence element including at least an inversion pulse and (ii) a data acquisition sequence executed after a delay time from the inversion pulse; and cause the scanner to execute the pulse sequence by using virtual gating.

A three-dimensional magnetic resonance image dataset of an object is acquired using a multi-shot imaging protocol in which several k-space lines are acquired in one shot. The three-dimensional k-space includes a central region and a periphery, wherein the sampling order of k-space lines differs between the central region and the periphery. At least one k-space line from each shot passes through the central region, whereas the periphery includes regions, which are sampled by k-space lines from a subset of the plurality of shots.