Abstract: The invention provides for a medical imaging system (100, 300). The execution of the machine executable instructions (110) causes a processor (102) to: receive (200) multiple diffusion weighted images (112) of a subject (318), wherein the multiple diffusion weighted images each have an assigned b-value, wherein the multiple diffusion weighted images each have an assigned diffusion weighting direction, wherein for a region of interest (309) there is at least one corresponding voxel (506) in each of the multiple diffusion weighted images; construct (202) a set of equations (114) for each of the at least one corresponding voxel, wherein the set of equations is constructed from an apparent diffusion equation for the assigned diffusion weighting direction of each of the multiple diffusion weighted images; solve (204) the set of equations for each voxel for the b0 value as an optimization; and construct (206) a b0 image using the b0 value for each voxel.

Abstract: Isotropic generalized diffusion tensor imaging methods and apparatus are configured to obtain signal attenuations using selected sets of applied magnetic field gradient directions whose averages produce mean apparent diffusion constants (mADCs) over a wide range of b-values, associated with higher order diffusion tensors (HOT). These sets are selected based on analytical descriptions of isotropic HOTs and the associated averaged signal attenuations are combined to produce mADCs, or probability density functions of intravoxel mADC distributions. Estimates of biologically-specific rotation-invariant parameters for quantifying tissue water mobilities or other tissue characteristics can be obtained such as Traces of HOTs associated with diffusion and mean t-kurtosis.

Abstract: The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). The method comprises the steps of: —generating MR signals by subjecting the object to an imaging sequence, —acquiring MR signal profiles in a Cartesian k-space sampling scheme, wherein each MR signal profile is acquired in the presence of a temporally constant magnetic field gradient along a readout direction and a sinusoidally modulated magnetic field gradient along a phase encoding direction, and—reconstructing an MR image from the acquired MR signal profiles taking the modulation scheme of the magnetic field gradients into account. The invention proposes that the frequency of the sinusoidal modulation of the magnetic field gradient is varied during acquisition of each MR signal profile. Moreover, the invention relates to a MR device for carrying out this method as well as to a computer program to be run on a MR device.

Abstract: Systems and methods for imaging a subject with a magnetic resonance imaging system using magnetic field gradients generated by one or more gradient coils operating with gradient coil settings, such as gradient amplitudes and gradient slew rates, above a threshold at which peripheral nerve stimulation is likely to be induced in the subject. A dielectric assembly is positioned adjacent a skin surface of the subject such that the dielectric assembly attenuates the local electric fields induced by the magnetic field gradients, which would be likely to induce PNS when the dielectric assembly is not arranged adjacent the skin surface of the subject. As a result of the dielectric assembly placed adjacent the skin surface of the subject, the gradient coil settings can be increased above the threshold without inducing PNS in the subject.

Abstract: The present disclosure is directed to radially-based magnetic resonance imaging. In any one or more embodiments, the present methods and systems provide that the angular increment between subsequent radial k-space spokes to be sampled to provide the imaging is performed for a predetermined or pre-defined restricted set of reconstruction window sizes (numbers of radial spokes per frame), or limited views, to maximize the uniformity of sampling within the restricted set of window sizes.

Abstract: Disclosed herein is a magnetic resonance imaging system (100) controlled by a processor (130). The execution of the machine executable instructions causes the processor to sort (200) multiple preparatory scan commands (142) into fixed duration preparatory scan commands (144) and indeterminate duration preparatory scan commands (146). The execution of the machine executable instructions further causes the processor to first control (202) the magnetic resonance imaging system with the indeterminate duration preparatory scan commands and then (204) with the fixed duration preparatory scan commands. The execution of the machine executable instructions further causes the processor to calculate (206) a gradient pulse starting time (160). The execution of the machine executable instructions further causes the processor to provide (208) the warning signal at a predetermined time (162) before the gradient pulse starting time.

Abstract: The present disclosure relates to a computer implemented diffusion magnetic resonance method for determining a diffusion parameter for spin-labelled particles in a specimen.

Abstract: A magnetic resonance imaging (MRI) system can include a processor and a memory. The processor can receive an acquired magnetic resonance (MR) dataset having a first signal-to-noise ratio (SNR). The processor can extract, from the acquired MR dataset, a first set of values corresponding to a first variable having a second SNR and a second set of values corresponding to a second variable. The processor can apply a constraint function that includes a function of the first variable and the second variable. The processor can minimize a cost function according to the constraint function to generate a cost function solution. The processor can input the first variable and the second variable into the cost function solution to generate a modified first variable having a third SNR, the third SNR being greater than the second SNR.

Abstract: A method for MRI reconstruction is provided. The method may include obtaining a plurality of sub-sampled images of a subject. The plurality of sub-sampled images may include a first sub-sampled image of the subject and one or more second sub-sampled images of the subject. The first sub-sampled image may be generated using a first MRI sequence and a first sub-sampling rate. Each of the one or more second sub-sampled images may be generated using a second MRI sequence and a second sub-sampling rate. The second sub-sampling rate may be smaller than the first sub-sampling rate. The method may include obtaining an image reconstruction model having been trained according to a machine learning technique. The method may further include generating a first full image of the subject corresponding to the first MRI sequence based on the first sub-sampled image, the one or more second sub-sampled images, and the image reconstruction model.

Abstract: A method for magnetic resonance imaging (MRI) may include cause, based on a pulse sequence, a magnetic resonance (MR) scanner to perform a scan on an object. The pulse sequence may include a steady-state sequence and an acquisition sequence that is different from the steady-state sequence. The steady-state sequence may correspond to a steady-state phase of the scan in which no MR data is acquired. The acquisition sequence may correspond to an acquisition phase of the scan in which MR data of the object is acquired. The method may also include generating one or more images of the object based on the MR data.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for harmonizing diffusion tensor images. One of the methods includes obtaining a diffusion tensor image; determining a set of RISH features for the diffusion tensor image; processing a model input generated from the set of RISH features using a machine learning model to generate a model output identifying an image transformation from a set of image transformations, wherein each image transformation in the set of image transformations corresponds to a respective different first MRI scanner and represents a transformation that, when applied to first diffusion tensor images captured by the first MRI scanner, harmonizes the first diffusion tensor images with second diffusion tensor images captured by a reference MRI scanner; and processing the diffusion tensor image using the identified image transformation to generate a harmonized diffusion tensor image.

Abstract: A computationally-designed instrumented intra-oral appliance to optimize the location and coupling of sensors to optimize data integrity while maximizing comfort for the wearer.

Abstract: The low-field nuclear magnetic resonance (LF-NMR) is used in the design of a formula of a water-based printing ink and selection of the water-based printing ink or a wetting agent. The water-based printing ink or the wetting agent is quickly selected through the inversion data of an LF-NMR transverse relaxation time (T2). By using LF-NMR to detect the distribution of water in the water-based printing ink or wetting agent, the water-based printing ink is quickly detected in real-time and a high-quality water-based printing ink is selected, which contributes to the design and development of water-based printing inks. The state of water in the ink also is adjusted based on the relationship between the distribution state of water in the printing ink and the definition of the printed pattern, thereby ensuring the definition of the printed pattern.

Abstract: The present disclosure is directed to techniques for actuation of a magnetic resonance device for generating a high frequency pulse for specific saturation of nuclear spins in an examination region of an examination object. The techniques may include providing a frequency spectrum of the examination region, providing a B0 field map, establishing a first resonance frequency for a first tissue and a second resonance frequency for a second tissue taking account of the frequency spectrum, determining a saturation pulse by establishing a high frequency pulse configured for a spectrally selective excitation of the first tissue and the second tissue taking account of the first resonance frequency, the second resonance frequency and the B0 field map, and outputting the saturation pulse by means of the high frequency antenna unit.

Abstract: A method for reconstructing single-slice image data sets from k-space measured data sets that have been acquired simultaneously from at least two slices from an examination object. The method includes an iterative modification and hence an optimization of the underlying k-space trajectories in the reconstruction of individual image data sets from collapsed measured data sets acquired from a plurality of slices and hence a retrospective reduction of interference in the individual image data sets that are obtained.

Abstract: A trolley system configured to transport a patient within an MRI environment includes a patient support portion, a base portion configured for movement relative to a floor, a lift coupled to the patient support portion and the base portion, an electric motor coupled to the lift, and an electric blower coupled to the patient transfer device. The lift is configured to change the elevation of the patient support portion relative to the base portion. The motor is mounted such that the elevation of the motor is fixed relative to base portion. The trolley system is positionable adjacent an MRI apparatus within the MRI environment and the magnetic field of the MRI does not interfere with the operation of the motor or blower. The trolley system may further include a patient transfer device having an air bearing. The blower is configured to deliver air to the air bearing.

Abstract: The present disclosure is directed to controlling a magnetic resonance imaging system for generating magnetic resonance image data from an object under examination, in which magnetic resonance raw data is captured, and at least one multi-slice STEAM pulse sequence is generated. The multi-slice STEAM pulse sequence comprises one excitation module for each slice, in each of which are generated a first slice-selective RF excitation pulse and a second slice-selective RF pulse, and one readout module for each slice for acquiring magnetic resonance raw data, which readout module comprises a third slice-selective RF pulse and further sequence elements for spatial encoding and for receiving RF signals. Between the excitation module and the readout module of a first slice is implemented at least one excitation module or one readout module for another slice.

Abstract: A signal processing method including receiving an original reference radio frequency signal from a receiving antenna group; receiving the time series of the control signal associated with the transmission event of the radio frequency pulses; synchronizing the time series with the original reference radio frequency signal, and determining the echo train in the original reference radio frequency signal in a repetition time of the pulse sequence, wherein the echo train corresponds to the part of the time series associated with the transmission event of the radio frequency pulses in time sequence; setting the sampling points in the domains of the starting point and a first ending point of the echo train; and generating a fitting signal based on the sampling points to eliminate the radio frequency interference signal resulted from the transmission event of the radio frequency pulses.

Abstract: A method a for acquiring magnetic resonance data of an object under examination by means of a magnetic resonance system comprises: in an excitation phase, applying an RF excitation pulse; in a wait phase following the excitation phase, applying at least one first RF refocusing pulse after the applied RF excitation pulse according to a first echo spacing; in an acquisition phase following the wait phase, applying at least two further RF refocusing pulses to generate echo signals according to a second echo spacing, wherein the second echo spacing is smaller than the first echo spacing; and reading out the echo signals generated in the acquisition phase as magnetic resonance data from which image data can be reconstructed, wherein in the wait phase at least two spoiler gradients are switched in the readout direction.

Abstract: A method and apparatus for susceptibility-weighted imaging, and a magnetic resonance imaging system. The method includes, in planar echo imaging of a plurality of excitations, performing flow compensation in directions of layered encoding, phase encoding, and frequency encoding for echoes of each excitation; after determination of excitation each time, when a linear reordering mode is adopted, for excitation each time, collecting each echo towards space k in a positive direction or a negative direction from the central echo of the plurality of echoes, and collecting echoes of the current excitation in a direction opposite to a direction of collecting echoes of the previous excitation; and subjecting the collected echoes to susceptibility-weighted imaging. An aspect of the present disclosure allows a reduction of flow artifacts in an image created by susceptibility-weighted imaging based on a planar echo sequence.