Abstract: A system for quantitative parameter mapping using magnetic resonance (MR) image includes an input for receiving a plurality of weighted MR images of a subject and a corresponding at least one imaging parameter for the plurality of weighted MR images, and a quantitative parameter mapping neural network coupled to the input and configured to estimate at least one tissue parameter and generate at least one quantitative map for the at least one tissue parameter based on the plurality of weighted MR images of the subject and the corresponding at least one imaging parameter. The quantitative parameter mapping neural network can be trained using a set of training data utilizing at least one confounder for the quantification of the at least one tissue parameter. The system can further include a display coupled to the quantitative parameter mapping neural network to display the at least one quantitative map.

Abstract: A method for generating a magnetic resonance (MR) image of a subject includes receiving an MR image of the subject reconstructed from undersampled MR data of the subject and providing the low resolution MR image of the subject to an image sharpness neural network. The image sharpness neural network can be implemented without an upsampling layer. The image sharpness neural network may be trained using a set of loss functions including an L1 Fast Fourier Transform (FFT) loss function. The method may further include generating an enhanced resolution MR image of the subject with increased sharpness based on the MR image of the subject using the image sharpness neural network.

Abstract: A system for quantitative parameter mapping using magnetic resonance (MR) image includes an input for receiving a plurality of weighted MR images of a subject and a corresponding at least one imaging parameter for the plurality of weighted MR images, and a quantitative parameter mapping neural network coupled to the input and configured to estimate at least one tissue parameter and generate at least one quantitative map for the at least one tissue parameter based on the plurality of weighted MR images of the subject and the corresponding at least one imaging parameter. The quantitative parameter mapping neural network can be trained using a set of training data utilizing at least one confounder for the quantification of the at least one tissue parameter. The system can further include a display coupled to the quantitative parameter mapping neural network to display the at least one quantitative map.

Abstract: A system and method for controlling a magnetic resonance imaging (MRI) system to acquire images of a subject having inconsistencies in a cardiac cycle of the subject. The process includes receiving an identification of a predetermined point in a cardiac cycle of the subject and, thereupon, performing a saturation module configured to dephase magnetization within a region of interest (ROI) from before the predetermined point. The process also includes performing an inversion module configured to invert spins within the ROI and acquiring medical imaging data from the subject. A delay is inserted between the performance of the saturation module and the performance of the inversion module, wherein a duration of the delay is configured, with the saturation module, to control evidence in the medical imaging data of inconsistencies in the cardiac cycle of the subject by controlling a magnetization history of tissue in the ROI.

Abstract: An MRI method includes: performing a first data acquisition block of a pulse sequence to acquire a first MR data from a plurality of slices of a subject during a period of fully recovered longitudinal magnetization within the plurality of slices disposed at different locations in the subject; performing a second data acquisition block of the pulse sequence including a magnetization preparation module followed by a recovery period and an imaging sequence executed during the recovery period, to acquire a second MR data from the plurality of slices during the recovery period; and generating a T1 map of the subject based on the first MR data and the second MR data, of the plurality of slices.

Abstract: A system and method for producing an image of a subject with a magnetic resonance imaging (MRI) system using an adaptive gating window with constant gating efficiency is provided. Navigator data is acquired from the subject and used to produce a gating window having a defined gating efficiency value. Image data is acquired with the MRI system while measuring a position of an anatomical location within the subject. Image data is accepted or rejected based on whether the measured anatomical location is within the gating window. The gating window is updated using the measured position of the anatomical location such that a substantially constant gating efficiency value is maintained. Imaging is repeated with the updated gating window, after which the gating window is again updated. When the desired amount of image data has been acquired, an image of the subject is reconstructed.

Abstract: An MRI apparatus includes: a data processor configured to acquire a first set of T2-weighted imaging data and a second set of T2-weighted imaging data; a pulse sequence controller configured to generate a pulse sequence and apply the generated pulse sequence to a gradient coil assembly and RF coil assembly, the generated pulse sequence including: T2-preparation modules and associated imaging modules to acquire the first set of T2-weighted imaging data, and a saturation pulse sequence and an associated saturation imaging module to acquire the second set of T2-weighted imaging data; a curve fitter configured to apply the first and second sets of T2-weighted imaging data to a three-parameter model for T2 decay, to determine a T2 value at a plurality of locations; and an image processor configured to generate a T2 map of the object based on the T2 value determined at the plurality of locations.

Abstract: A system and method for acquiring magnetic resonance imaging (MRI) images with an MRI system is provided. The system and method directs the MRI system first to produce an inversion recovery radio frequency (RF) pulse, wait for a time period, produce a T2-preparation RF pulse, wait for another time period, and then acquire data of a part of a subject. The first produced RF pulse rotates net magnetization 180 degrees about an axis. The pulse sequence used to acquire data can be any two-dimensional or three-dimensional sequence used to acquire a volume in the subject. The two waiting time periods are chosen such that the signals of two or more tissues of the subject are nulled.

Abstract: An MRI method includes performing a first image acquisition module of a pulse sequence to acquire a first MR data from slices disposed at different locations in a region of interest (ROI) of an object; performing a second image acquisition module of the pulse sequence, to acquire a second MR data from the slices disposed at the different locations of the ROI, with a T2 preparation time different than that of the first image acquisition module; and generating a T2 map based on the acquired first MR data and the acquired second MR data.

Abstract: A method and apparatus for reducing scan time, eddy currents and image factors in dynamic magnetic resonance (MR) imaging associated with at least a portion a k-space. The method includes scanning at least a portion of the k-space with an Echo-Planar Imaging (EPI) pulse sequence technique, acquiring a randomly under-sampled k-space; and reconstructing the under-sampled k-space utilizing a constrained reconstruction technique. A dynamic image is constructed of the at least a portion of the k-space based on EPI and the randomly undersampled k-space techniques to each segment of the EPI pulse sequence technique.

Abstract: A system and method for acquiring magnetic resonance imaging (MRI) images with an MRI system is provided. The system and method directs the MRI system first to produce an inversion recovery radio frequency (RF) pulse, wait for a time period, produce a T2-preparation RF pulse, wait for another time period, and then acquire data of a part of a subject. The first produced RF pulse rotates net magnetization 180 degrees about an axis. The pulse sequence used to acquire data can be any two-dimensional or three-dimensional sequence used to acquire a volume in the subject. The two waiting time periods are chosen such that the signals of two or more tissues of the subject are nulled.

Abstract: A magnetic resonance imaging (MRI) system and methods are provided for producing images of a subject. In some aspects, a method includes identifying a point in the cardiac cycle, performing an inversion recovery (IR) pulse at a selected time point from the pre-determined point, and sampling a k-space segment at an inversion time from the IR pulse that is substantially coincident with the pre-determined point. The method also includes repeating the IR pulse and k-space sampling for multiple inversion times, and multiple segments of k-space, in an interleaved manner, to generate datasets having T1-weighted contrasts determined by their respective inversion times. The method further includes reconstructing three-dimensional (3D) spatially-aligned images using the datasets, and generating a T1 recovery map by combining the 3D images. In some aspects, a prospective/retrospective scheme may be used to obtain data fully sampled in the center of k-space and randomly undersampled in the outer regions.

Abstract: A method and apparatus for MRI retrospective reconstruction determines a period of minimal coronary artery motion within the acquired temporal window with a rotation angle optimized for a K-space four-dimensional (4D) volume by a segmented 4D radial stack-of-stars (SOS) acquisition during a temporal acquisition window (taw). Radial stacks of the image of an object are acquired by performing the radial (SOS) acquisition to determine a plurality of kz plane samples of the object, in which each kz plane is repeatedly determined during a sub-window of the temporal acquisition window. Consecutive volumes of kz centric slices of the image at each temporal sub-window of the temporal acquisition window are generated and summed to fill a 3D k-space volume. The radial (SOS) acquisition of the image is determined utilizing a customized rotation angle ? providing a uniform distribution of k-space spokes of the kz centric slices for each sub-window of the (taw).

Abstract: A magnetic resonance (MR) image processing system includes a data collection unit that acquires image data from a target region of an object. A navigator unit acquires a motion signal indicating motion comprising motion of at least a portion of an object. A data processing unit derives k-space data for a k-space data array from the acquired image data, by acquiring k-space data for a first portion of the k-space from the acquired image data in response to the motion signal indicating motion is within a predetermined range and acquiring k-space data for a second portion of the k-space from the acquired image data irrespective of the predetermined range.

Abstract: An MRI method includes performing a first image acquisition module of a pulse sequence to acquire a first MR data from slices disposed at different locations in a region of interest (ROI) of an object; performing a second image acquisition module of the pulse sequence, to acquire a second MR data from the slices disposed at the different locations of the ROI, with a T2 preparation time different than that of the first image acquisition module; and generating a T2 map based on the acquired first MR data and the acquired second MR data.

Abstract: A method for free-breathing magnetic resonance imaging (MRI) using iterative image-based respiratory motion correction is provided. An MRI system is used to acquired k-space data and navigator data from a subject. The k-space data is then sorted into a plurality of data bins using the navigator data. A motion correction parameter is estimated for each data bin and is applied to the respective k-space data in that bin. The corrected k-space data segments are then combined to form a corrected k-space data set, from which an image is reconstructed. The process may be iteratively repeated until an image quality metric is optimized; for example, until an image sharpness measure is sufficiently maximized.

Abstract: An apparatus and method process image data, including motion corrupted data, from a magnetic resonance imaging procedure to obtain and reconstruct images for cardiac, cardiovascular, coronary arterial, and/or pulmonary vein diagnoses in a subject. The apparatus and method include a processor operating predetermined software which receives the image data, classifies the received image data as accepted image data or rejected image data, and applies a predetermined relationship between the accepted image data and the rejected image data to correct for motion of the subject and to generate and output a reconstructed image of the subject corrected for the motion from the image data, with the reconstructed image having a relatively high signal-to-noise ratio.

Abstract: An MRI method includes: performing a first data acquisition block of a pulse sequence to acquire a first MR data from a plurality of slices of a subject during a period of fully recovered longitudinal magnetization within the plurality of slices disposed at different locations in the subject; performing a second data acquisition block of the pulse sequence including a magnetization preparation module followed by a recovery period and an imaging sequence executed during the recovery period, to acquire a second MR data from the plurality of slices during the recovery period; and generating a T1 map of the subject based on the first MR data and the second MR data, of the plurality of slices.

Abstract: A method and apparatus for MRI retrospective reconstruction determines a period of minimal coronary artery motion within the acquired temporal window with a rotation angle optimized for a K-space four-dimensional (4D) volume by a segmented 4D radial stack-of-stars (SOS) acquisition during a temporal acquisition window (taw). Radial stacks of the image of an object are acquired by performing the radial (SOS) acquisition to determine a plurality of kz plane samples of the object, in which each kz plane is repeatedly determined during a sub-window of the temporal acquisition window. Consecutive volumes of kz centric slices of the image at each temporal sub-window of the temporal acquisition window are generated and summed to fill a 3D k-space volume. The radial (SOS) acquisition of the image is determined utilizing a customized rotation angle ? providing a uniform distribution of k-space spokes of the kz centric slices for each sub-window of the (taw).

Abstract: An MRI apparatus includes: a data processor configured to acquire a first set of T2-weighted imaging data and a second set of T2-weighted imaging data; a pulse sequence controller configured to generate a pulse sequence and apply the generated pulse sequence to a gradient coil assembly and RF coil assembly, the generated pulse sequence including: T2-preparation modules and associated imaging modules to acquire the first set of T2-weighted imaging data, and a saturation pulse sequence and an associated saturation imaging module to acquire the second set of T2-weighted imaging data; a curve fitter configured to apply the first and second sets of T2-weighted imaging data to a three-parameter model for T2 decay, to determine a T2 value at a plurality of locations; and an image processor configured to generate a T2 map of the object based on the T2 value determined at the plurality of locations.