Abstract: Systems and methods for suppressing Nyquist ghost for diffusion weighted magnetic resonance imaging are disclosed. An exemplary method includes acquiring multiple k-space data sets using multiple sets of diffusion weighted imaging pulse sequences, reconstructing a magnetic resonance image from each of the multiple k-space data sets respectively, and averaging magnitudes of the magnetic resonance images to generate an average magnitude magnetic resonance image.

Abstract: Systems and methods for suppressing Nyquist ghost for diffusion weighted magnetic resonance imaging are disclosed. An exemplary method includes acquiring multiple k-space data sets using multiple sets of diffusion weighted imaging pulse sequences, reconstructing a magnetic resonance image from each of the multiple k-space data sets respectively, and averaging magnitudes of the magnetic resonance images to generate an average magnitude magnetic resonance image.

Abstract: Embodiments of the present invention provide a motion tracking method for MR imaging, comprising: exciting an imaging volume of a detected object; shifting a frequency of an FID signal generated by the imaging volume relative to a center frequency as a position of the imaging volume changes; acquiring the FID signal and calculating a frequency shift of the acquired FID signal relative to the center frequency for multiple times; and obtaining a motion trajectory of the detected object in accordance with a change of the frequency shift as a function of time.

Abstract: Embodiments of the present invention provide a magnetic resonance imaging method and system and a computer-readable storage medium.

Abstract: Methods and apparatuses for processing MR signal are disclosed herein. An exemplary method comprises: when acquired K-space signals are amplified, assigning a first amplification gain to signals within a first signal region in the K space, and assigning a second amplification gain to signals within a second signal region in the K space.

Abstract: Systems and methods for suppressing background in time-of-flight (TOF) magnetic resonance angiography (MRA) are disclosed. An exemplary method includes obtaining a first TOF image through a high-resolution acquisition with a saturation band on one side of an imaging slab, obtaining a second TOF image through a low-resolution acquisition with two saturation bands on both sides of the imaging slab, and subtracting the second TOF image from the first TOF image to obtaining a subtraction TOF image. Post processing such as maximum intensity projection (MIP) is performed on the subtraction TOF image.

Abstract: Systems and methods for suppressing background in time-of-flight (TOF) magnetic resonance angiography (MRA) are disclosed. An exemplary method includes obtaining a first TOF image through a high-resolution acquisition with a saturation band on one side of an imaging slab, obtaining a second TOF image through a low-resolution acquisition with two saturation bands on both sides of the imaging slab, and subtracting the second TOF image from the first TOF image to obtaining a subtraction TOF image. Post processing such as maximum intensity projection (MIP) is performed on the subtraction TOF image.

Abstract: Embodiments of the present invention provide a magnetic resonance imaging system and a method for obtaining magnetic resonance imaging data. The method comprises: applying a fat suppression pulse before the start of any repetition time of an imaging sequence; performing a plurality of echoes in the repetition time, wherein first image data when water and fat are in phase and second image data when water and fat are out of phase are obtained during each echo of the plurality of echoes; and obtaining fat-suppressed image data according to the first image data and the second image data.

Abstract: Various methods and systems are provided for scanning an image subject along a scan axis. The method includes stitching sectional datasets acquired from different anatomical sections of the image subject based on locations of a landmark in the sectional datasets.

Abstract: Various methods and systems are provided for acquiring k-space data for magnetic resonance imaging. In one example, after applying a phase encoding gradient, the k-space data of a phase angle is acquired while applying a frequency encoding gradient. An amplitude of the phase encoding gradient and a duration of the phase encoding gradient determined based on each and every of a phase angle of the phase encoding line and a duration of the frequency encoding gradient.

Abstract: The present invention provides a method and apparatus for correcting a uniformity of a magnetic resonance image, the method including: acquiring a first uniformity enhancement image by a phased-array uniformity enhancement method; and dividing the first uniformity enhancement image by a receiving sensitivity distribution value of a body coil in a magnetic resonance imaging device, so as to acquire a second uniformity enhancement image. The method further includes: dividing the second uniformity enhancement image by a spatial signal distribution value resulting from a field strength distribution of a transmitting radio-frequency field, so as to acquire a third uniformity enhancement image.

Abstract: Spike noise in a k-space dataset acquired in magnetic resonance imaging may be removed by generating a mask including a set of data points which constitute spike noise in the k-space dataset based on the acquired k-space dataset via a trained deep learning network, the mask corresponding to a location of the spike noise in the acquired k-space dataset. An image reconstructed based on the acquired k-space dataset and the mask may be displayed.

Abstract: Methods and apparatuses for calibrating a center frequency of MR and an MRI system are disclosed herein. An exemplary method comprises applying a first set of gradient fields, receiving data information acquired by an RF coil and generating a first image; applying a second set of gradient fields in directions different than those of the first set of gradient fields, receiving data information acquired by the RF coil and generating a second image; calculating a shift of the center frequency based on the first image and the second image; and correcting the center frequency based on the shift of the center frequency.

Abstract: Various methods and systems are provided for scanning an image subject along a scan axis. The method includes stitching sectional datasets acquired from different anatomical sections of the image subject based on locations of a landmark in the sectional datasets.

Abstract: Various methods and systems are provided for acquiring k-space data for magnetic resonance imaging. In one example, after applying a phase encoding gradient, the k-space data of a phase angle is acquired while applying a frequency encoding gradient. An amplitude of the phase encoding gradient and a duration of the phase encoding gradient determined based on each and every of a phase angle of the phase encoding line and a duration of the frequency encoding gradient.

Abstract: The present invention provides a magnetic resonance imaging method and system, the method comprising performing the following steps at least once: a composition step: performing image composition processing on raw images received by a receiving coil that is pre-determined as an artifact coil and a receiving coil that is pre-determined as a non-artifact coil to obtain a composite image; and a correction step: obtaining a product of the above composite image and space sensitivity of the above artifact coil to replace the raw image received by the above artifact coil, and performing the above composition step again.

Abstract: Methods and apparatuses for calibrating a center frequency of MR and an MRI system are disclosed herein. An exemplary method comprises applying a first set of gradient fields, receiving data information acquired by an RF coil and generating a first image; applying a second set of gradient fields in directions different than those of the first set of gradient fields, receiving data information acquired by the RF coil and generating a second image; calculating a shift of the center frequency based on the first image and the second image; and correcting the center frequency based on the shift of the center frequency.

Abstract: Embodiments of the present invention provide a motion tracking method for MR imaging, comprising: exciting an imaging volume of a detected object; shifting a frequency of an FID signal generated by the imaging volume relative to a center frequency as a position of the imaging volume changes; acquiring the FID signal and calculating a frequency shift of the acquired FID signal relative to the center frequency for multiple times; and obtaining a motion trajectory of the detected object in accordance with a change of the frequency shift as a function of time.

Abstract: The present invention provides an apparatus and method for controlling a pulse sequence of a magnetic resonance (MR) imaging system, the MR imaging system comprising a radio frequency magnetic field coil and a gradient magnetic field coil, the apparatus for controlling a pulse sequence of the MR imaging system comprising a radio frequency driving unit and a gradient driving unit. The gradient driving unit is used for applying a first motion probing gradient (MPG) pulse and a second MPG pulse to the gradient magnetic field coil successively.

Abstract: Methods and apparatuses for processing MR signal are disclosed herein. An exemplary method comprises: when acquired K-space signals are amplified, assigning a first amplification gain to signals within a first signal region in the K space, and assigning a second amplification gain to signals within a second signal region in the K space.