Patent classifications
G01R33/4826
Motion determination for volumetric magnetic resonance imaging using a deep machine-learning model
For determination of motion artifact in MR imaging, motion of the patient in three dimensions is used with a measurement k-space line order based on one or more actual imaging sequences to generate training data. The MR scan of the ground truth three-dimensional (3D) representation subjected to 3D motion is simulated using the realistic line order. The difference between the resulting reconstructed 3D representation and the ground truth 3D representation is used in machine-based deep learning to train a network to predict motion artifact or level given an input 3D representation from a scan of a patient. The architecture of the network may be defined to deal with anisotropic data from the MR scan.
Motion correction for magnetic resonance angiography (MRA) with 3D radial acquisitions
A magnetic resonance imaging (MRI) system, method and/or computer readable medium is configured to effect magnetic resonance angiography (MRA) images with reduced motion artifacts includes acquiring a plurality of k-space data sets by traversing a plurality of radial trajectories in three-dimensional (3D) k-space, generating a plurality of 3D MR images derived from k-space populated by the k-space data sets, aligning the 3D MR images with respect to each other, determining one or more motion parameters for the object based upon the aligning, modifying values of k-space data sets using the determined one or more motion parameters, generating a motion-corrected 3D MR image from a combination of acquired k-space data sets including the modified values.
Method and magnetic resonance system to acquire MR data in a predetermined volume segment
In a method and magnetic resonance (MR) system to acquire MR data in a predetermined volume segment of an examination subject, the data are acquired with at least one echo train that includes at least two signal echoes. The same number of echoes is acquired for each echo train of the at least one echo train, with this number of echoes corresponding to an echo train length. The total number of echoes that are required to acquire the MR data and the echo train length is adapted so that the total number corresponds to a whole number multiple of the echo train length.
Magnetic resonance (MR) imaging generating perfusion images with arterial spin labeling (ASL) and 3D radial pulse sequences
Systems and methods for reducing acoustic noise in a Magnetic Resonance Imaging (MRI) are provided. One method includes applying a labeling phase of an arterial spin labeling (ASL) pulse sequence to a region of interest, applying a three-dimensional (3D) radial pulse sequence to the region of interest to generate a tag image, applying a control phase of the ASL pulse sequence to the region of interest, and applying the 3D radial pulse sequence to the region of interest to generate a control image.
SPIRAL SHAPED MR ACQUISITION TEMPLATE
A method for generating at least one acquisition template for an acquisition of magnetic resonance signals, an acquisition template generating unit, a magnetic resonance apparatus and a computer program product. At least one acquisition template is generated with an acquisition template generating unit. The at least one acquisition template has a plurality of spiral-like spokes in a k-space, each spoke having a plurality of spiral points.
EFFICIENT SELF-REFOCUSING ZERO ECHO TIME MR IMAGING
The invention relates to a method of MR imaging of an object positioned in an examination volume of a MR device (1). It is an object of the invention to enable efficient silent ZTE imaging with self-refocusing. The method of the invention comprises the steps of:—specification of a set of radial k-space spokes to cover a spherical k-space volume;—selection of subsets of a predetermined number of spokes from the specified set so that the concatenation of the spokes contained in each of the subsets forms a closed trajectory in k-space, wherein the selection of the subsets involves optimizing a cost function;—subjecting the object (10) to a zero echo time imaging sequence, wherein each of the subsets of spokes is acquired as a sequence of gradient echo signals; and—reconstructing an MR image from the acquired spokes. Moreover, the invention relates to a MR device and to a computer program for a MR device.
ENHANCEMENTS TO QUANTITATIVE MAGNETIC RESONANCE IMAGING TECHNIQUES
Systems and methods providing enhancements to quantitative imaging systems and techniques are described herein. In one aspect, a system for tissue quantification in magnetic resonance fingerprinting (MRF) comprises a feature extraction module operable to convert pixel input high-dimensional signal evolution in to a low-dimensional feature map. The system also comprises a spatially constrained quantification module operable to capture spatial information from the low-dimensional feature map and generate an estimated tissue property map.
Method of performing magnetic resonance imaging and a magnetic resonance apparatus
In a method of performing magnetic resonance (MR) imaging, an MR apparatus, and a computer-readable medium during a first cardiac cycle of a subject, a first imaging sequence is generated for application to a subject. The first imaging sequence has a preparatory pulse and an inversion recovery pulse following the preparatory pulse. First signals emitted from the subject in response to the first imaging sequence are detected, and first image data are generated based on the first signals. During a second cardiac cycle following the first cardiac cycle, a second imaging sequence is generated for application to the subject. The second imaging sequence has a preparatory pulse. Second signals emitted from the subject in response to the second imaging sequence are detected, and second image data are generated based on the second signals.
METHOD AND APPARATUS FOR GENERATING A MAGNETIC RESONANCE IMAGE WITH RADIO COLLECTION OF MAGNETIC RESONANCE DATA TO AVOID IMAGE ARTIFACTS
For the creation of a magnetic resonance (MR) image of a predetermined volume section of an object of investigation, MR data of the volume section are collected along radial trajectories, and each trajectory is assigned a readout direction in which the MR data are collected along the respective trajectory. The MR image is reconstructed on the basis of the collected MR data. In the reconstruction, only MR data are taken into consideration that were collected along trajectories with a readout direction restricted to the field of a solid angle that is defined by a partial surface of a sphere. The partial surface (A) at most corresponds to 75% of the total surface of the sphere.
MAGNETIC RESONANCE IMAGING METHOD
A magnetic resonance imaging method executed in a magnetic resonance imaging apparatus according to an embodiment comprises: applying an inversion pulse; executing a subsequent imaging sequence including an RF (Radio Frequency) pulse and a gradient magnetic field concurrently applied with the RF pulse in a slice direction and performing, for a slice position selected by the RF pulse and the gradient magnetic field and during a time period including a null point, data acquisition in a plurality of orientations including a center of a two-dimensional k-space.