A correction method for reducing temperature-related deviations in a gradient response of an MR pulse sequence in MR imaging is provided. An MR pulse sequence that includes at least one nominal test gradient is run. A gradient response to the at least one nominal test gradient is repeatedly acquired by a magnetic field measurement in an examination region. A gradient system transfer function is determined based on the gradient response. A corrected MR pulse sequence is determined based on the gradient system transfer function and of the at least one nominal test gradient.

An apparatus to jointly measure oxygen utilization and tissue strain includes an imaging system and a computer processor operatively coupled to the imaging system. The computer processor is configured to control the imaging system to perform a pulse sequence on tissue of a subject. The computer processor also acquires oxygen utilization data and strain data responsive to the pulse sequence. The computer processor further determines an amount of strain on the tissue of the subject based at least in part on the strain data and an amount of oxygen utilization of the tissue of the subject based at least in part on the oxygen utilization data.

Methods, computing devices, and MRI systems that reduce artifacts produced by Maxwell gradient terms in TSE imaging using non-rectilinear trajectories are disclosed. With this technology, a RF excitation pulse is generated to produce transverse magnetization that generates a NMR signal and a series of RF refocusing pulses to produce a corresponding series of NMR spin-echo signals. An original encoding gradient waveform comprising a non-rectilinear trajectory is modified by adjusting a portion of the original encoding gradient waveform or introducing a zero zeroth-moment waveform segment at end(s) of the original encoding gradient waveform. During an interval adjacent to each of the series of RF refocusing pulses a first gradient pulse is generated. At least one of the first gradient pulses is generated according to the modified gradient waveform. An image is constructed from generated digitized samples of the NMR spin-echo signals obtained.

According to one embodiment, a medical information processing apparatus has processing circuitry. The processing circuitry acquires medical data on a subject, acquires numerical data obtained by digitizing an acquisition condition of the medical data, and applies a machine learning model to input data including the numerical data and the medical data, thereby generating output data based on the medical data.

This specification describes systems and methods for using Zero Echo Time (ZTE) magnetic resonance imaging (MRI) sequences for applications to functional MRI (fMRI). In some examples, a system for functional magnetic resonance imaging includes a magnetic resonance imaging (MRI) scanner and a control console implemented on at least one processor. The control console is configured for executing, using the MRI scanner, a zero echo time (ZTE) pulse sequence; acquiring, using the MRI scanner, magnetic resonance data in response to the ZTE pulse sequence; and constructing at least one MRI image using the magnetic resonance data and measuring tissue oxygenation (PtO2)-related T1 changes as a proxy of neural activity changes of a subject using the at least one MRI image.

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.

A magnetic resonance tomography unit and a method is provided in which a patient couch may be moved in relation to the longitudinal direction into the patient tunnel in the transversal direction into a left-hand side extreme position and an opposite-lying right-hand side extreme position. Using an image acquisition facility in the left-hand side extreme position a right-hand side part is acquired and in the right-hand side extreme position a left-hand side part of the outer contour of the predetermined object is acquired. Using the image acquisition facility, the outer contour of the object is subsequently created from the left-hand side part of the outer contour and also from the right-hand side part of the outer contour.

A system and method for performing accelerated k-space shift correction calibration scans for non-Cartesian trajectories is provided. The method can include applying an MRI sequence, performing a calibration scan based on the MRI sequence using the non-Cartesian trajectory to acquire k-space shift data, wherein one or more partitions are skipped during the calibration scan, interpolating the skipped one or more partitions using the k-space shift data from adjacent partitions, and calibrating the MRI system using the k-space shift data and the interpolated k-space shift data. In some embodiments, an acceleration factor Acc can be defined and the calibration scan acquires k-space shift data for only one partition in every Acc partitions.

A method for producing a streak-suppressed MR image of a subject includes (i) generating an interference correlation matrix from M coil images, (ii) producing eigenvectors of the interference correlation matrix, and (iii) determining, from the subspace-eigenvectors, a projection matrix of the interference null space. The subspace-eigenvectors include a plurality of subspace-eigenvectors that span an interference subspace and a plurality of null-space-eigenvectors that span an interference null space. The method also includes generating, from N coil images derived from a respective one of N MR signals, N streak-suppressed multi-coil images by either (i) preprocessing the N coil images with the projection matrix and applying an image-reconstruction technique to each of the resultant N preprocessed coil images, or (ii) applying an image-reconstruction technique to each of the N coil images to obtain N reconstructed coil images and post-processing the resultant N reconstructed coil images with the projection matrix.

A method for generating a magnetic resonance image includes providing MR segment data records, wherein each MR segment data record has N×M frequency voxels in k-space. To reduce the acquisition time during MR segment recordings, the amount of MR data is reduced by incompletely sampling the k-space during a recording. The missing data of the MR segment data records are reconstructed twice: Preliminarily reconstructed MR segment data records are calculated first, with a reconstruction kernel obtained from reference data. Modified reference images containing phase information are obtained by creating phase images from the preliminarily reconstructed MR segment data records and combining these phase images with the absolute value of the reference image generated from the reference data. The second reconstruction kernels are ascertained therefrom in turn. In contrast to the first reconstruction kernel, these contain phase information, such that the missing data can be reconstructed without phase artifacts.