Patent classifications
G01R33/5616
Mutli-shot magnetic resonance imaging system and method
The present invention provides a magnetic resonance imaging system for imaging a subject by a multi-shot imaging. The magnetic resonance imaging system comprises an acquiring unit for acquiring MR raw data corresponding to a plurality of shots; an imaging unit for generating a plurality of folded images from the MR raw data, wherein each of the plurality of folded images is generated from a subset of the MR raw data; a deriving unit for deriving magnitude of each pixel of each folded image; a detecting unit for detecting a motion of the subject during the multi-shot imaging based on similarity measurements of any two folded images of the plurality of folded images, wherein the detecting unit further comprises a first deriving unit configured to derive the measured similarities; and a reconstructing unit for reconstructing a MR image of the subject based on MR raw data obtained according to a detection result of the detecting unit. Since the partially acquired MR raw data is used for motion detection directly, it would be more rapid and stable.
METHOD OF REMOVING GHOST ARTIFACTS FROM MAGNETIC RESONANCE IMAGE, AND MAGNETIC RESONANCE APPARATUS THEREFOR
A method of reconstructing a magnetic resonance image includes receiving echo planar imaging (EPI) data, acquiring an even scan line image and an odd scan line image from k-space data of the EPI data, and reconstructing missing portions of the even scan line image and the odd scan line image.
RAPID MEASUREMENT OF PERFUSION USING OPTIMIZED MAGNETIC RESONANCE FINGERPRINTING
Described here are systems and methods for generating quantitative perfusion parameter maps based on different longitudinal relaxation parameter maps that are produced from images acquired using non-selective and selective magnetic resonance imaging (“MRI”) data acquisition techniques.
Method and system for creating magnetic resonance images
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.
MAGNETIC BARCODE IMAGING
Provided herein is technology relating to magnetic resonance imaging contrast agents and particularly, but not exclusively, to methods and systems for visualizing one or more magnetic resonance imaging contrast agent.
MAGNETIC RESONANCE IMAGING DEVICE
There is provided a technique for DWI measurement, in which MPG application is performed in many directions, that enables detection of presence or absence of body motion during imaging without prolongation of imaging time. A plurality of image groups each comprising 6 or more diffusion-weighted images selected from a plurality of diffusion-weighted images are created so the groups differ from one anther in one or more diffusion-weighted images included in each of the groups. Value of a predetermined diffusion index representing a characteristic amount of diffusion-weighted image is calculated for each image group from the diffusion-weighted images included in each image group. Value of a predetermined body motion index relating to body motion information is calculated from the value of the diffusion index for each image group. Presence or absence of body motion is determined for each image group on the basis of the value of the body motion index.
SYSTEMS AND METHODS FOR HANDLING PEAK POWER REQUIREMENTS OF A MEDICAL IMAGING DEVICE
A method of handling a peak power requirement of a medical imaging device 106 is presented. The method includes determining, using at least one controlling unit 107, 108, a first voltage corresponding to a direct current (DC) link 116, a second voltage corresponding to one or more energy storage devices 110, or a combination thereof, where a power source 102 is coupled to a plurality of loads via the DC link, and the energy storage devices are coupled to the DC link. Further, the method includes comparing, using the at least one controlling unit, the first voltage with a first reference value and the second voltage with a second reference value and regulating, using at least one controlling unit, at least one of the first voltage and the second voltage based on the comparison, to handle the peak power requirement of the medical imaging device.
System and method for rapid, multi-shot segmented magnetic resonance imaging
A system and method for medical imaging using a magnetic resonance imaging system includes performing a segmented echo planar imaging (EPI) pulse sequence. The pulse sequence includes performing multiple radio frequency (RF) excitation pulses designed to excite multiple imaging slices across the subject simultaneously. A gradient encoding scheme applied along the slice-encoding direction is implemented to impart controlled phase shifts to the different imaging slices. Additionally, the multiple RF excitation pulses can be designed to further control an overlap of imaging data acquired from adjacent slices of the multiple imaging slices based on a selected offset. The acquired imaging data is reconstructed using a parallel imaging reconstruction method that separates overlapped slices in the imaging data to provide a series of images with respective images for each of the multiple imaging slices across the subject.
CARDIAC PHASE-RESOLVED NON-BREATH-HOLD 3-DIMENSIONAL MAGNETIC RESONANCE ANGIOGRAPHY
3D cine MR angiography systems and methods are disclosed for use during the steady state intravascular distribution phase of ferumoxytol. The 3D cine MRA technique enables improved delineation of cardiac anatomy in pediatric patients undergoing cardiovascular MRI.
SYSTEM AND METHOD FOR DUAL-KERNEL IMAGE RECONSTRUCTION
A method and imaging system is provided that can control a magnetic gradient system and an RF system of an MRI system according to a calibration pulse sequence to acquire positive readout gradient (RO+) data and negative readout gradient (RO−) data. The RO+ data and the RQ− data are assembled to form complete image data sets for the RO+ data and the RQ™ data and the RO+ data and the RO− data are combined to generate the calibration data that is ghost-corrected, substantially free of ghost artifacts, or having reduced ghost artifacts compared to traditionally-acquired calibration data. Reconstruction coefficients are derived from the calibration data. The magnetic gradient system and the RF system are controlled according to an imaging pulse sequence to acquire image data and the image data is reconstructed into an image of the subject using the reconstruction coefficients.