A method is provided for magnetic resonance (MR) imaging near metal, including acquiring an image at a first magnetic field from a subject that includes a metal object, acquiring an image at a second magnetic field, and combining the images to provide a corrected image with reduced metal distortion. An MR imaging system for measuring near metal is also provided including a superconducting magnet to provide a magnetic field, a power supply for a current to ramp the magnetic field, a cryocooler in contact with the superconducting magnet, a magnetic field controller programmed to ramp the main magnetic field by adjusting the current generated by the power supply, a radio frequency system for transmitting and receiving signals, and a data aquisition and processing system to receive the MR signals, generate image data sets and combine the image data sets to provide a corrected image having a reduced metal distortion.

Systems and methods for quantitative susceptibility mapping (QSM) using magnetic resonance imaging (MRI) are described. Localized magnetic field information is used when performing the inversion to compute quantitative susceptibility maps. The localized magnetic field information can include multi-resolution subvolumes obtained by segmenting, or dividing, a field shift map. In some instances, a trained machine learning algorithm, such as a trained neural network, can be implemented to convert the localized magnetic field information into quantitative susceptibility data. These local susceptibility maps can be combined to form a composite quantitative susceptibility map of the imaging volume.

Described here are systems and methods for using a magnetic resonance imaging (MRI) system to estimate parameters of spectral profiles contained in multispectral data acquired using multispectral imaging (MSI) techniques, such as MAVRIC. These spectral profile parameters are reliably extracted using an iterative perturbation theory technique and utilized in a number of different applications, including fat suppression, artifact correction, and providing accelerated data acquisitions.

A method is provided for magnetic resonance (MR) imaging near metal, including acquiring an image at a first magnetic field from a subject that includes a metal object, acquiring an image at a second magnetic field, and combining the images to provide a corrected image with reduced metal distortion. An MR imaging system for measuring near metal is also provided including a superconducting magnet to provide a magnetic field, a power supply for a current to ramp the magnetic field, a cryocooler in contact with the superconducting magnet, a magnetic field controller programmed to ramp the main magnetic field by adjusting the current generated by the power supply, a radio frequency system for transmitting and receiving signals, and a data aquisition and processing system to receive the MR signals, generate image data sets and combine the image data sets to provide a corrected image having a reduced metal distortion.

The invention relates to a magnetic resonance imaging system (10), the system comprising a magnetic resonance imaging device (12) for acquiring data from a moving subject (14), especially a fetus or a part of said fetus; and an image generator (30) for generating an image of said moving subject (14), wherein the magnetic resonance imaging device (12) is configured to acquire the data from the subject (14) at different positions of said subject (14) with respect to a magnetization direction B.sub.0, utilizing the movement of the subject (14); and wherein the image generator (30) is configured to determine the position and/or orientation of said subject (14) during the respective data acquisition; reconstruct phase images from the acquired data; and generate a susceptibility map based on the reconstructed phase images. The invention further relates to a corresponding method for generating an image of the subject (14).

Provided is an image processor including a tissue-segmentation-processing-unit that performs tissue segmentation processing on at least one of a plurality of complex images generated based on a magnetic resonance signal generated from a subject to calculate a tissue-image related to a predetermined specific tissue, a magnetic-susceptibility-image-calculation-unit that calculates a magnetic-susceptibility-image showing magnetic susceptibility of a predetermined tissue included in the complex image from the complex image, an anatomical-standardization-processing-unit that calculates a standard-magnetic-susceptibility-image and a spatially-normalized tissue-image by performing spatially normalization processing on the magnetic-susceptibility-image and the tissue-image and calculates a volume modulated spatially-normalized tissue-image obtained by performing volume modulation on the spatially-normalized tissue-image, a magnetic-susceptibility-calculation-unit that calculates magnetic susceptibility of the specific tissue based on the spatially-normalized -magnetic-susceptibility-image and the spatially-normalized tissue-image, and a diagnostic-index-calculation-unit that calculates a diagnostic index for diagnosing a predetermined disease based on the magnetic susceptibility of the specific tissue and the volume modulated spatially-normalized tissue-image.

In general, according to the present embodiment, a magnetic resonance imaging apparatus includes sequence control circuitry and processing circuitry. The sequence control circuitry collects MR data corresponding to each of a plurality of echo times. The processing circuitry generates a plurality of magnitude images corresponding to the plurality of echo times based on the MR data. The processing circuitry generates a relaxation time map of tissue based on the plurality of magnitude images. The processing circuitry generates a susceptibility map quantitatively indicating susceptibility values in a subject based on a magnetic field distribution that is generated based on a plurality of phase images corresponding to the plurality of echo times and the relaxation time map.

Artifacts caused by metallic needles used in MRI-guided procedures such as tumor biopsies significantly decrease the visibility of therapy targets and diminish the ability of the physician to accurately monitor and perform the procedure. As described in the present application, a needle including active shimming can self-compensate for these artifacts and significantly improve the visualization and monitoring of targeted tissue. The accuracy and overall outcomes of MRI-guided treatments can be significantly improved with the use of the needle.

Techniques are disclosed for recording magnetic resonance data with a magnetic resonance facility, wherein a three-dimensional echo-planar imaging sequence is used whereby following a single excitation period (e.g. module) in an echo train, an echo count of k-space rows is read out in a read-out direction in the k-space, and interchanging takes place between these rows by means of gradient pulses of the two phase encoding directions.

The present disclosure is related to systems and methods for determining a field map in magnetic resonance imaging (MRI). The method includes obtaining at least three images. Each may be acquired at one of at least three echo times by an MRI device via scanning a subject. The at least three echo times may define multiple pairs of adjacent echo times. Each of the multiple pairs of adjacent echo times may have a time difference between the adjacent echo times. At least two of the time differences may be different. The method includes determining a target function with an off-resonance frequency as an independent variable. The target function includes a phase deviation term and a sparsity constraint term.