Abstract: The present disclosure provides a system for MRI. The system may obtain a plurality of echo signals relating to a subject that are excited by an MRI pulse sequence applied to the subject. The system may perform a quantitative measurement on the subject based on the plurality of echo signals. The MRI pulse sequence may include a CEST module configured to selectively excite exchangeable protons or exchangeable molecules in the subject, an RF excitation pulse applied after the CEST module configured to excite a plurality of gradient echoes, and one or more refocusing pulses applied after the RF excitation pulse. Each of the refocusing pulses may be configured to excite one or more spin echoes. The one or more spin echoes excited by at least one of the one or more refocusing pulses may include a symmetric spin echo and one or more asymmetric spin echoes.

Abstract: 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.

Abstract: The present disclosure may provide imaging method and system. The method may include obtaining a plurality of signals relating to a region of interest (ROI) of an object acquired by applying to the object a plurality of chemical exchange and saturation transfer (CEST) preparations with a plurality of offset frequencies; and generating an image of the ROI based on the plurality of signals. The plurality of CEST preparations may be configured to excite proton exchange of a substance in the ROI. The plurality of CEST preparations may be divided into one or more groups. Each of the one or more groups may include multiple CEST preparations with a same offset frequency among the plurality of offset frequencies. After a last CEST preparation in each of the one or more groups is applied to the object, the substance may reach a saturation degree that exceeds a saturation threshold.

Abstract: A system, method, and computer-readable medium for evaluating structural integrity of a gradient coil disposed in a magnetic resonance imaging system is provided. A sensor obtains a parameter reading of the gradient coil, wherein the parameter reading includes a back electromotive force (back EMF) measurement. The structural integrity of the gradient coil is determined as function of the back EMF measurement.

Abstract: The disclosure relates to a technique for providing an image of diagnostically relevant area of a jaw region of a patient by means of a magnetic resonance apparatus by capturing information about the jaw region of the patient, which comprises at least one reference to a position and/or an extent of the diagnostically relevant area of the jaw region. The technique also includes adjusting a parameter of a magnetic resonance measurement as a function of the captured information about the jaw region of the patient, carrying out the magnetic resonance measurement with the adjusted parameter, capturing image data of the jaw region of the patient, reconstructing an image of the diagnostically relevant area of the jaw region as a function of the captured image data, and providing the image of the diagnostically relevant area of the jaw region of the patient.

Abstract: Systems and methods for data transmission may be provided. The system may at least include a data transmission module. The system may obtain MR signals from one or more RF coils. The system may generate, via a first portion of the data transmitting module, first data based on the MR signals. The system may generate, via a second portion of the data transmitting module, second data based on the first data. The second portion of the data transmitting module may connect to the first portion of the data transmitting module wirelessly. The system may further store the second data in a non-transitory computer-readable storage medium.

Abstract: A method for performing real-time magnetic resonance (MR) imaging on a subject is disclosed. A prep pulse sequence is applied to the subject to obtain a high-quality special subspace, and a direct linear mapping from k-space training data to subspace coordinates. A live pulse sequence is then applied to the subject. During the live pulse sequence, real-time images are constructed using a fast matrix multiplication procedure on a single instance of the k-space training readout (e.g., a single k-space line or trajectory), which can be acquired at a high temporal rate.

Abstract: A magnetic resonance imaging apparatus according to an embodiment includes processing circuitry. The processing circuitry sets a pulse sequence to collect plural echo signals by application of a refocusing pulse more than once after application of an excitation pulse once, and collects data on plural slices that are parallel to each other by executing the pulse sequence more than once. The processing circuitry sets the pulse sequence such that a slice thickness for the refocusing pulse becomes larger than a slice thickness for the excitation pulse, and collects the data on the plural slices by executing the pulse sequence without consecutively collecting data on adjacent ones of the plural slices.

Abstract: Appropriate processing is executed in a method for excluding body motion data and image reconstruction according to a type and a characteristic of a body motion, so as to reduce an influence of the body motion, and prevent deterioration of image quality caused by exclusion of data generated during the body motion. An MRI apparatus includes a processing determination unit that collects k-space data and acquires body motion information from a sensor capable of detecting not only a respiratory motion but also general body motions, analyzes the body motion information obtained by the sensor, and branches and executes processing for subsequent data collection and image reconstruction according to the analysis result.

Abstract: Provided herein are methods and systems for high-resolution, cerebrospinal fluid-suppressed T2*-weighted magnetic resonance imaging of cortical lesions.

Abstract: It is an object of the invention to improve processes, apparatuses and systems for measuring a measured variable. To this end, a measured variable is measured in a measuring process on the basis of an NV center as a quantum sensor. The NV center has a plurality of quantum states and is optically excitable on the basis of an occupancy of one of the quantum states into at least one excited state of the quantum states by means of an excitation light. The at least one excited state can decay at least with emission of emission light of the NV center. In the measuring process, the NV center is irradiated by the excitation light, the excitation light having a time periodic modulation, and a respective occupancy probability and/or a respective lifetime of the quantum states depending on the measured variable and the excitation light.

Abstract: Systems and methods provide accelerated MR thermometry utilizing prior knowledge about the images to be reconstructed from incomplete k-space data, thereby facilitating accurate reconstruction. In various embodiments, missing data is computationally estimated using a machine learning algorithm such as a neural network, and an image is generated based on iteratively updated estimated missing information.

Abstract: Various embodiments of a system and associated method for whole-blade acquisition and phase correction for fast and robust MR imaging are disclosed herein. In particular, the system enables sampling of odd and even k-space echoes in the same k-space as well as a whole-blade phase correction strategy to achieve improved image quality at an accelerated imaging rate.

Abstract: Distortion generated in an image is effectively corrected in imaging using an EPI sequence such as DWI without extending an imaging time. After one excitation RF pulse of EPI is applied, a navigator scan in which the polarity of the phase encoding is opposite to that of the main scan is performed continuously to the main scan, and the distortion of the image by using the navigator scan data obtained by the navigator scan is corrected. In a case of multi-shot, phase information obtained from the navigator scan data for each shot is used to perform phase correction and multi-shot reconstruction on the main scan data of each shot.

Abstract: Higher quality diffusion metrics and/or diffusion-weighted images are generated from lower quality input diffusion-weighted images using a suitably trained neural network (or other machine learning algorithm). High-fidelity scalar and orientational diffusion metrics can be extracted using a theoretical minimum of a single non-diffusion-weighted image and six diffusion-weighted images, achieved with data-driven supervised deep learning. As an example, a deep convolutional neural network (“CNN”) is used to map the input non-diffusion-weighted image and diffusion-weighted images sampled along six optimized diffusion-encoding directions to the residuals between the input and output high-quality non-diffusion-weighted image and diffusion-weighted images, which enables residual learning to boost the performance of CNN and full tensor fitting to generate any scalar and orientational diffusion metrics.

Abstract: Described here are systems and methods for producing images with a magnetic resonance imaging (“MRI”) system using a high-resolution, motion-robust, artifact-free segmented echo planar imaging (“EPI”) technique. In particular, a fast low angle excitation echo planar imaging technique (“FLEET”) using variable flip angle (“VFA”) radio frequency (“RF”) excitation pulses that are recursively designed to have a flat magnitude and phase profile across a slice for a range of different flip angles by accounting for longitudinal magnetization remaining after each preceding RF pulse is applied.

Abstract: The invention relates to a method of MR imaging of an object (10). It is an object of the invention to enable MR imaging using a 3D radial or spiral acquisition scheme providing an enhanced image quality in the presence of motion. The method comprises the steps of: —generating MR signals by subjecting the object (10) to an imaging sequence comprising RF pulses and switched magnetic field gradients; —acquiring the MR signals using a 3D radial or spiral acquisition scheme with oversampling of a central portion (26) of k-space; —detecting motion-induced displacements (d) and/or deformations of the object (10) during the acquisition of the MR signals and assigning each of the acquired MR signals to a motion state; —reconstructing an MR image from the MR signals weighted in the central portion (26) of k-space, wherein a stronger weighting (W, 30) is applied to MR signals acquired in more frequent motion states, while a weaker weighting (W, 31, 32) is applied to MR signals acquired in less frequent motion states.

Abstract: Techniques are provided for imaging a subject. A magnetic resonance imaging (MRI) system may use at least one RF coil to generate an initial MR data set for an initial image of the subject. The MRI system may use the initial MR image to determine a difference in orientation between a current orientation of the subject in the initial MR image and a target orientation of the subject. The MRI system may use the determined difference in orientation to determine an adjustment to a gradient pulse sequence for controlling at least one gradient coil. The MRI system may apply the determined adjustment to the gradient pulse sequence to obtain an adjusted gradient pulse sequence. The MRI system may generate an adjusted MR data set using the adjusted gradient pulse sequence, and a second MR image of the subject using the adjusted MR data set.

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.