G01R33/56545

Comprehensive cardiovascular analysis with volumetric phase-contrast MRI

Processing techniques of volumetric anatomic and vector field data from volumetric phase-contrast MRI on a magnetic resonance imaging (MRI) system are provided to evaluate the physiology of the heart and vessels. This method includes the steps of: (1) correcting for phase-error in the source data, (2) visualizing the vector field superimposed on the anatomic data, (3) using this visualization to select and view planes in the volume, and (4) using these planes to delineate the boundaries of the heart and vessels so that measurements of the heart and vessels can be accurately obtained.

Method and magnetic resonance apparatus for distortion correction of acquired scan data of an examination object from an enlarged field of view and returning to a desired field of view thereafter
10495716 · 2019-12-03 · ·

In a method and a magnetic resonance (MR) apparatus for distortion correction of MR-acquired scan data of an object, an entry is made into a computer in order to select desired field of view (FOV), in which scan data of the object under examination (U) is to be acquired. An enlarged field of view (gFOV) is created in the computer by enlarging the desired field of view (FOV) in at least one spatial direction. An MR scanner is operated in order to acquire MR scan data in the enlarged field of view. Distortions are corrected in a data set based on scan data from the enlarged field of view, by applying a distortion correction algorithm to that data set. The corrected data set is reduced in the computer to the desired field of view. The reduced corrected data set is made available from the computer for storage and/or display.

SYSTEMS AND METHODS FOR IMPROVING MAGNETIC RESONANCE IMAGING USING DEEP LEARNING
20190347772 · 2019-11-14 ·

A computer-implemented method is provided for improving image quality with shortened acquisition time. The method comprises: determining an accelerated image acquisition scheme for imaging a subject using a medical imaging apparatus; acquiring a medical image of the subject according to the accelerated image acquisition scheme using the medical imaging apparatus; applying a deep network model to the medical image to improve the quality of the medical image; and outputting an improved quality image of the subject, for analysis by a physician.

STREAK ARTIFACT REDUCTION IN MAGNETIC RESONANCE IMAGING

For radial sampling in magnetic resonance imaging (MRI), a rescaling factor is determined from k-space data for each coil. The rescale factor is inversely proportional to the streak energy in the k-space data. The k-space data from the coils is rescaled for reconstruction, such as weighting the k-space data by the rescale factor in a data consistency term of iterative reconstruction. The rescale factor is additionally or alternatively used to determine a correction field for correction of intensity bias applied to intensities in the image-object space after reconstruction. These approaches may result in a diagnostically useful bias-corrected image with reduced streak artifact while benefiting from the efficient computation (i.e., computer operates to reconstruct more quickly).

Magnetic resonance system and shimming method and imaging method thereof

Embodiments of the present application provide a magnetic resonance system and a shimming method and an imaging method thereof. The shimming method comprises: performing a scout scan on a subject to be examined, and obtaining phase data of a plurality of slice positions; determining three-dimensional space static magnetic field information according to the phase data of the plurality of slice positions; and determining a shimming value of a slice in a region of interest according to the three-dimensional space static magnetic field information.

Iterative reconstruction of gradient echo Magnetic Resonance Images

Disclosed herein is a medical system (100, 300). The execution of machine executable instructions (120) causes a processor (104) to: receive (200) measured gradient echo k-space data (122); receive (202) an off-resonance phase map (124); reconstruct (204) an initial image (126) from the measured gradient echo k-space data; calculate (206) an upsampled phase map (128) from the off-resonance phase map; calculate (208) an upsampled image (130) from the initial image; calculating (210) a modulated image (132) by modulating the upsampled image with the upsampled phase map; calculate (212) a corrected image (134) comprising iteratively. The iterative calculation comprises: calculating (214) updated k-space data by applying a data consistency algorithm (138) to a k-space representation of the modulated image and the measured gradient echo k-space data and calculating (216) an updated image (142) from the updated k-space data. Calculation of the updated image comprises demodulation by the upsampled phase map and applying a smoothing algorithm.

System and method for reducing partial voluming artifacts in quantitative myocardial tissue characterization

A system and method for obtaining magnetic resonance images are provided. The system is programmed to control the RF system to apply a saturation pulse at a reference frequency that saturates a selected labile spin species of the subject. The system is programmed to control the RF system to apply an inversion pulse after a variable delay. The system is programmed to control the RF system and the plurality of gradient coils to apply a motion sensitized driven equilibrium (MSDE) preparation pulse. The system is programmed to control the plurality of gradient coils to read imaging data during an acquisition time period. The system is programmed to reconstruct a T.sub.1 mapping image of the subject with black-blood contrast.

METHOD AND APPARATUS FOR ACQUIRING MAGNETIC RESONANCE DATA DIXON METHOD WITH FLEXIBLE ECHO TIMES
20190310335 · 2019-10-10 · ·

In a magnetic resonance (MR) method and apparatus for determining an MR image or an MR fat image of an examination subject, first and second MR signal datasets are provided to a computer, respectively obtained at first and second echo times. The computer defines a signal model and determines possible solution candidates for values of parameters of the signal model for each pixel of the two MR signal datasets so that the MR signals thereof are matched as well as possible. A correct solution is selected from the solution candidates, using a calculated phase map, based on predetermined assumptions regarding the calculated phase map. The MR water image or the MR fat image is determined using the correct solution.

Magnetic resonance imaging apparatus

A magnetic resonance imaging apparatus according to an embodiment includes processing circuitry. By using image data of a subject acquired by performing a first imaging process, the processing circuitry is configured to detect a first region including at least a part of a first site, the first site and a second site having a symmetrical relationship with each other in the subject. The processing circuitry is configured to derive a second region including at least a part of the second site on the basis of the first region. The processing circuitry is configured to set a Radio Frequency (RF) pulse application region used for performing a second imaging process, on the basis of the second region.

System and Method for Phase Unwrapping for Automatic Cine DENSE Strain Analysis Using Phase Predictions and Region Growing

In one aspect the disclosed technology relates to embodiments of a method (e.g., for automatic cine DENSE strain analysis) which includes acquiring magnetic resonance data associated with a physiological activity in an area of interest of a subject where the acquired magnetic resonance data includes one or more phase-encoded data sets. The method also includes determining, from at least the one or more phase-encoded data sets, a data set corresponding to the physiological activity in the area of interest where the reconstruction comprises performing phase unwrapping of the phase-encoded data set using region growing along multiple pathways based on phase predictions.