Abstract: Embodiments associated with combined magnetic resonance angiography and perfusion (MRAP) and nuclear magnetic resonance (NMR) fingerprinting are described. One example apparatus repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The apparatus includes a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals. The apparatus includes an MRAP logic that simultaneously performs MR angiography and produces quantitative perfusion maps. A multi-factor MR bio-imaging panel is produced from a combination of the data provided by the MRAP and NMR fingerprinting. Diagnoses may be made from the multi-factor MR bio-imaging panel.

Abstract: Example embodiments associated with characterizing a sample using NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. The NMR signals are produced in response to a FISP-MRF pulse sequence. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a tissue in the object as a result of comparing acquired signals to reference signals. Acquired signals are corrected using data describing an inhomogeneous B1 field produced by the NMR apparatus while the set of NMR signals are acquired.

Abstract: Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic configured to repetitively and variably sample a (k, t, E) space associated with an object to acquire a set of NMR signals. Members of the set of NMR signals are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The varying parameters may include flip angle, echo time, RF amplitude, and other parameters. The NMR apparatus may also include a signal logic configured to produce an NMR signal evolution from the NMR signals, a matching logic configured to compare a signal evolution to a known, simulated or predicted signal evolution, and a characterization logic configured to characterize a resonant species in the object as a result of the signal evolution comparisons.

Abstract: Example embodiments associated with characterizing a sample using NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a tissue in the object as a result of comparing acquired signals to reference signals. Example embodiments facilitate analyzing voxels having multiple compartments that may experience magnetic exchange. The compartments may be, for example, an intracellular volume and an extracellular volume in a tissue that experiences magnetic exchange due to the movement of water between the volumes.

Abstract: Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance renography (MRR). Example apparatus and methods reconstruct under-sampled three-dimensional (3D) data associated with nuclear magnetic resonance (NMR) signals acquired from a kidney. The data is reconstructed using a 3D through-time non-Cartesian generalized auto-calibrating partially parallel acquisitions (GRAPPA) approach. Example apparatus and methods produce a quantized value for a contrast agent concentration in the kidney from a signal intensity in the data based, at least in part, on a two compartment model of the kidney. The two compartment model includes a plasma compartment and a tubular compartment. The quantized value describes a perfusion parameter for the kidney or a filtration parameter for the kidney.

Abstract: Systems and methods for acquiring three-dimensional imaging data from a breast of a subject includes acquiring, with a nuclear magnetic resonance (NMR) system, NMR data from a volume of interest (VOI) including a breast by acquiring data in a series of variable sequence blocks. A sequence block includes one or more excitation phases, one or more readout phases, and one or more waiting phases, to cause one or more resonant species in the breast to simultaneously produce individual NMR signals. Also, at least one member of the series of variable sequence blocks differs from at least one other member of the series of variable sequence blocks in at least N sequence block parameters, N being an integer greater than one. The method also includes comparing the NMR data to a dictionary of signal evolutions from breast tissue and generating a report indicating quantitative tissue parameters over the breast.

Abstract: A system and method for generating quantitative images of a subject using a nuclear magnetic resonance system. The method includes performing a navigator module to acquire navigator data, and performing an acquisition module during free breathing of the subject to acquire NMR data from the subject that contains one or more resonant species that simultaneously produce individual NMR signals in response to the acquisition module. The above steps are repeated to acquire data from a plurality of partitions across the volume. The navigator data is analyzed to determine if the NMR data meets a predetermined condition and if not, the above steps are repeated for at least an affected partition corresponding to NMR data that did not meet the predetermined condition. The NMR data is compared to a dictionary of signal evolutions to determine quantitative values for two or more parameters of the resonant species in the volume.

Abstract: Systems, methods, apparatus, and other embodiments associated with reducing imaging acquisition time are described. One example method includes accessing an under-sampled data set and a library of previously acquired data sets. The method includes producing an approximation of the under-sampled data set by transforming data stored in the library. The method includes producing a sparsified data set from the approximation and the under-sampled data set and then reconstructing the sparsified data set into a sparse image using a reconstruction technique configured to reconstruct sparse data. The method includes producing a fully-sampled approximation of the under-sampled data set and producing a final reconstructed image from the sparse image and the fully sampled approximation.

Abstract: Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance imaging (MRI) for a large (e.g., 500 cm3) three dimensional (3D) volume. Example apparatus and methods reconstruct under-sampled 3D data associated with nuclear magnetic resonance (NMR) signals acquired from the volume using a 3D through-time non-Cartesian generalized auto-calibrating partially parallel acquisitions (GRAPPA) approach. The NMR signals are produced in response to a 3D non-Cartesian (e.g., stack-of-spirals) pulse sequence. Example apparatus and methods produce a quantified value for T1 relaxation, T2 relaxation, diffusion, or other NMR parameters in the volume from signal intensities in the data. The quantified value may describe, for example, a perfusion parameter, a blood flow parameter, a blood volume parameter, or other value.

Abstract: Three-dimensional (3D) projections of nuclear magnetic resonance (NMR) signals are acquired from a liver experiencing NMR in response to a 3D multi-echo non-Cartesian pulse sequence. The projections are reconstructed into two sets of images having different resolutions. Bins associated with the different positions to which the liver moves during respiration are identified in lower resolution images, and then higher resolution images are binned into the position dependent bins based on navigator data in the lower resolution images. A combined image for a bin is made from images located in the bin and then registered to a reference image. An overall combined image is made by summing the combined bin images. Quantized data for a contrast agent concentration in the liver is produced using signal intensity in the overall combined image. The quantized value may describe a liver perfusion parameter. A diagnosis may be made from the quantized value.

Abstract: Example embodiments associated with characterizing a sample using NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a tissue in the object as a result of comparing acquired signals to reference signals. Example embodiments facilitate analyzing voxels having multiple compartments that may experience magnetic exchange. The compartments may be, for example, an intracellular volume and an extracellular volume in a tissue that experiences magnetic exchange due to the movement of water between the volumes.

Abstract: Example embodiments associated with characterizing a sample using NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. The NMR signals are produced in response to a FISP-MRF pulse sequence. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a tissue in the object as a result of comparing acquired signals to reference signals. Acquired signals are corrected using data describing an inhomogeneous B1 field produced by the NMR apparatus while the set of NMR signals are acquired.

Abstract: Apparatus, methods, and other embodiments associated with magnetic resonance (MR) trajectory correcting using GRAPPA operator gridding (GROG) are described. One example method includes identifying an on angle or regular portion of a projection in an MR trajectory and then computing base GROG weights for that portion. The example method includes identifying a shift direction and a shift amount for the projection. The shift direction is configured to shift the projection towards a desired point in k-space and the shift amount is configured to shift the projection by a desired amount in the shift direction. With a shift direction and amount available, the example method corrects for a gradient delay by manipulating the MR source signal data using the shift direction and the shift amount. In one embodiment, a gradient delay can be determined and used to calibrate an MRI apparatus.

Abstract: Embodiments associated with combined magnetic resonance angiography and perfusion (MRAP) and nuclear magnetic resonance (NMR) fingerprinting are described. One example apparatus repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The apparatus includes a signal logic that produces an NMR signal evolution from the NMR signals and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals. The apparatus includes an MRAP logic that simultaneously performs MR angiography and produces quantitative perfusion maps. A multi-factor MR bio-imaging panel is produced from a combination of the data provided by the MRAP and NMR fingerprinting. Diagnoses may be made from the multi-factor MR bio-imaging panel.

Abstract: Example apparatus and methods control a magnetic resonance imaging (MRI) apparatus to acquire, from an object to be imaged, throughout a period of time, a partitioned non-Cartesian fully-sampled calibration data set. Different groups of lines in the calibration data set are acquired at different points in time under different gradient encoding conditions that yield phase encoding in the direction perpendicular to the non-Cartesian encoded plane. The MRI apparatus is controlled to acquire an under-sampled non-Cartesian data set from the object to be imaged and to reconstruct an image from the under-sampled data set based, at least in part, on a through-time GRAPPA calibration. A GRAPPA weight set can be computed from data in different groups of lines in the calibration data set because different groups of lines can be treated as unique calibration time frames due to phase encoding produced by the different gradient encoding conditions.

Abstract: Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance imaging (MRI) for a large (e.g., 500 cm3) three dimensional (3D) volume. Example apparatus and methods reconstruct under-sampled 3D data associated with nuclear magnetic resonance (NMR) signals acquired from the volume using a 3D through-time non-Cartesian generalized auto-calibrating partially parallel acquisitions (GRAPPA) approach. The NMR signals are produced in response to a 3D non-Cartesian (e.g., stack-of-spirals) pulse sequence. Example apparatus and methods produce a quantified value for T1 relaxation, T2 relaxation, diffusion, or other NMR parameters in the volume from signal intensities in the data. The quantified value may describe, for example, a perfusion parameter, a blood flow parameter, a blood volume parameter, or other value.

Abstract: Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance imaging (MRI) of the liver. Example apparatus and methods reconstruct under-sampled three-dimensional (3D) data associated with nuclear magnetic resonance (NMR) signals acquired from a liver. The data is reconstructed using a 3D through-time non-Cartesian generalized auto-calibrating partially parallel acquisitions (GRAPPA) approach. Example apparatus and methods produce a quantized value for a contrast agent concentration in the liver from a signal intensity in the data based, at least in part, on a compartment model of the liver. The quantized value describes a perfusion parameter for the liver. Greater precision is achieved for estimates of the perfusion parameter as a result of the quantization performed on data acquired with greater spatial resolution and temporal resolution.

Abstract: Three-dimensional (3D) projections of nuclear magnetic resonance (NMR) signals are acquired from a liver experiencing NMR in response to a 3D multi-echo non-Cartesian pulse sequence. The projections are reconstructed into two sets of images having different resolutions. Bins associated with the different positions to which the liver moves during respiration are identified in lower resolution images, and then higher resolution images are binned into the position dependent bins based on navigator data in the lower resolution images. A combined image for a bin is made from images located in the bin and then registered to a reference image. An overall combined image is made by summing the combined bin images. Quantized data for a contrast agent concentration in the liver is produced using signal intensity in the overall combined image. The quantized value may describe a liver perfusion parameter. A diagnosis may be made from the quantized value.

Abstract: Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance renography (MRR). Example apparatus and methods reconstruct under-sampled three-dimensional (3D) data associated with nuclear magnetic resonance (NMR) signals acquired from a kidney. The data is reconstructed using a 3D through-time non-Cartesian generalized auto-calibrating partially parallel acquisitions (GRAPPA) approach. Example apparatus and methods produce a quantized value for a contrast agent concentration in the kidney from a signal intensity in the data based, at least in part, on a two compartment model of the kidney. The two compartment model includes a plasma compartment and a tubular compartment. The quantized value describes a perfusion parameter for the kidney or a filtration parameter for the kidney.

Abstract: Apparatus, methods, and other embodiments associated with combined correlation parameter estimation are described. One example method includes accessing data associated with a magnetic resonance (MR) signal produced by relaxation of nuclei in an item that has experienced nuclear magnetic resonance (NMR) excitation. The MR signal is a function of two or more NMR parameters. The example method also includes accessing data associated with a set of comparative signal evolutions and computing a value for an NMR parameter based on a combined correlation of the data associated with the MR signal to the data associated with the set of comparative signal evolutions. The combined correlation will depend on at least two correlations between the data associated with the MR signal and two different members of the set of comparative signal evolutions.