Patent classifications
G01R33/4818
System and method for producing temporally resolved images depicting late-gadolinium enhancement with magnetic resonance imaging
Systems and methods for late gadolinium enhancement (“LGE”) tissue viability imaging in a dynamic (e.g., temporally-resolved) manner using magnetic resonance imaging (“MRI”) are provided. Dynamic LGE images can be generated throughout the entire cardiac cycle at high temporal resolution in a single breath-hold. Dynamic, semi-quantitative longitudinal relaxation maps are acquired and retrospective synthetization of dynamic LGE images is implemented using those semi-quantitative longitudinal relaxation maps.
Adaptive Reconstruction of MR Data
An adaptive reconstruction of MR data, including acquired MR data of a core region having core segments and simulated MR data of a peripheral region. The method includes ascertaining a peripheral signal based on the MR data of the peripheral region, determining a scaling factor for each core segment by taking into account the peripheral signal and a mean signal intensity of the MR data for the respective core segment, scaling the MR data of the core region by taking into account the MR data of each core segment and that of the scaling factor corresponding to the respective core segment, generating filtered MR data by combining the scaled MR data of the core region with the MR data of the peripheral region, and reconstructing image data from the filtered MR data.
Magnetic Resonance Imaging with a Dynamic Diffusion-Weighting
In a method for diffusion-weighted MR-imaging of an object, which undergoes a cyclic motion, a first sub-period type of the cyclic motion is predicted for a first acquisition timeframe, where the first sub-period type corresponds to one of two or more predefined characteristic types of sub-periods of the cyclic motion. A first amount of diffusion-weighting may be selected based on the first sub-period type. A first MR-acquisition may be carried out during the first acquisition timeframe, where a diffusion-weighting according to the first amount of diffusion-weighting is applied. An MR-image of the object is generated based on MR-data including a first MR-dataset obtained as a result of the first MR-acquisition.
Creating Calibration Data for Completing Undersampled Measurement Data of an Object to be Examined by Means of a Magnetic Resonance System
Calibration data is generated for completing undersampled measurement data acquired via a magnetic resonance system. This includes recording N measurement data sets using an acquisition scheme, and undersampling the k-space with an acceleration factor R, with N being greater than or equal to R, and the N measurement data sets together scanning the k-space completely. Phase images are generated from the N recorded measurement data sets, at least one homogeneity value of the created phase images is determined, and a complete calibration data set is generated based upon the recorded measurement data sets, taking into account the at least one homogeneity value. Thus, it is possible to determine which measurement data sets are subject to undesired phase errors, the measurement data sets used for the creation of the calibration data sets can be selected optimally, and input of the detected phase errors into the calibration data sets can be avoided.
Systems and Methods for Spiral-In-Out Low Field MRI Scans
Systems and methods for performing ungated magnetic resonance imaging are disclosed herein. A method includes producing magnetic resonance image MRI data by scanning a target in a low magnetic field with a pulse sequence having a spiral trajectory; sampling k-space data from respective scans in the low magnetic field and receiving at least one field map data acquisition and a series of MRI data acquisitions from the respective scans; forming a field map and multiple sensitivity maps in image space from the field map data acquisition; forming target k-space data with the series of MRI data acquisitions; forming initial magnetic resonance images in the image domain by applying a Non-Uniform Fast Fourier Transform to the target k-space data; and forming reconstructed images with a low rank plus sparse (L+S) reconstruction algorithm applied to the initial magnetic resonance images.
Method for operating a magnetic resonance apparatus, magnetic resonance apparatus, computer program and electronically readable data storage medium
In a method for operating a magnetic resonance (MR) apparatus, MR raw-data is acquired from an acquisition region of a patient for a sampling region of k-space using a MR sequence that employs ultrashort echo times; a first MR image dataset is reconstructed from the MR raw-data of the k-space region; a second MR image dataset is reconstructed from the MR raw-data in a central subregion of the sampling region in k-space; a resolution of the second MR image dataset is interpolated to increase the resolution of the second MR image dataset to a resolution of the first magnetic resonance image dataset; and the first and second MR image datasets are combined to obtain an output MR image dataset.
Magnetic resonance imaging apparatus and magnetic resonance imaging method
In MRI, upon simultaneously generating computed images of multiple parameters, imaging time is efficiently reduced while preventing decrease in spatial resolution and SN ratio as much as possible. A plurality of original images is reconstructed from nuclear magnetic resonance signals acquired under various imaging conditions, and a computed image is obtained by calculation performed among the plurality of original images. The various imaging conditions include an imaging condition that a repetition time of an imaging sequence is different from one another, and upon imaging, the number of phase encoding steps is made smaller when the repetition time is long. An image is reconstructed in such a manner that a matrix size of the image obtained when the number of phase encoding steps is small is made equal to the matrix size of the image obtained when the number of phase encoding steps is large.
IMAGE RECONSTRUCTION METHOD
A computer-implemented method of reconstructing a motion-compensated magnetic resonance image uses raw k-space data acquired at a first resolution over successive respiratory and/or cardiac cycles of a patient. After binning data based on corresponding motion states derived from these cycles, the resolution of the binned K-space data in each bin is reduced. This is done by selecting a sub-group of binned k-space data. Bin images are reconstructed from the reduced-resolution data, and histogram-equalised versions of the reconstructed reduced-resolution bin image generated for each bin. Motion fields are estimated and interpolated to the first resolution such that motion data can be incorporated into a final reconstruction of a motion compensated image.
TECHNIQUES FOR DETERMINING A FUNCTIONAL MAGNETIC RESONANCE DATA SET
Techniques for determining a functional magnetic resonance data set of an imaging region of a brain of a patient are disclosed in which blood oxygenation level dependent functional magnetic resonance imaging is used. The techniques include using a plurality of reception coils, and acquiring magnetic resonance signals using parallel imaging and a magnetic resonance sequence defining a k-space trajectory, wherein undersampling in at least two k-space directions is performed. The techniques further include reconstructing the functional magnetic resonance data set from the magnetic resonance signals and sensitivity information regarding the plurality of reception coils using a reconstruction technique for undersampled magnetic resonance data, wherein the k-space trajectory is chosen to allow controlled aliasing in all three spatial dimensions including the readout direction.
SYSTEM, APPARATUS, AND METHOD FOR INCREMENTAL MOTION CORRECTION IN MAGNETIC RESONANCE IMAGING
An apparatus for incremental motion correction in medical imaging. The apparatus for motion correction in magnetic resonance imaging includes processing circuitry configured to estimate an intermediate image from a first section of k-space, the first section of the k-space corresponding to acquisition time points within a magnetic resonance scan of a subject, the corresponding acquisition time points within the magnetic resonance scan being associated with shots of the k-space determined to have minimal motion, estimate motion parameters of a second section of the k-space using the estimated intermediate image, combine data from the first section of the k-space with data from the second section of the k-space according to the estimated motion parameters, and reconstruct the combined data of the k-space to generate a final image.