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 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. Sampling is performed in response to a diffusion-weighted double-echo pulse sequence. Sampling acquires transient-state signals of the double-echo sequence. 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 resonant species in the object as a result of comparing acquired signals to reference signals.

Abstract: Apparatus, methods, and other embodiments associated with 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 resonant species in the object as a result of comparing acquired signals to reference signals. The NMR signal evolution may be assigned to a cluster based on the characterization of the resonant species. Cluster overlay maps may be produced simultaneously based, at least in part, on the clustering. The clusters may be associated with different tissue types.

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: A system and method is provided for operating a high-field magnetic resonance (MR) system includes performing a series of data acquisition modules without respiratory gating. Each data acquisition module is formed of a steady-state free precession pulse sequence. Performing the series of data acquisition modules includes varying at least one of an amplitude of an excitation pulse or a repetition time of the steady-state free precession pulse sequence between adjacent data acquisition modules in the series of data acquisition modules to acquire a series of MR data with random or pseudo-random imaging acquisition parameters. The series of MR data is compared to a dictionary of signal evolution profiles to determine a match between the series of MR data with at least one signal evolution profile in the dictionary indicating at least one quantitative parameter in the subject.

Abstract: Apparatus, methods, and other embodiments associated with 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 resonant species in the object as a result of comparing acquired signals to reference signals. The NMR signal evolution may be assigned to a cluster based on the characterization of the resonant species. Cluster overlay maps may be produced simultaneously based, at least in part, on the clustering. The clusters may be associated with different tissue types.

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: Example apparatus and methods perform magnetic resonance fingerprinting (MRF) for arterial spin labeling (ASL) based parameter quantification. ASL with MRF produces a nuclear magnetic resonance signal time course from which simultaneous quantification of ASL perfusion-related parameters can be achieved. The parameters may include cerebral blood flow, transit time, T1, or other parameters. The quantification uses values from a dictionary of signal time courses that were generated or augmented using Bloch simulation, knowledge of the sequence, or previous observations. The dictionary may account for inflow or outflow of labeled spins and may model arterial input. An ASL-MRF pulse sequence may differ from conventional pulse sequences. For example, an ASL-MRF pulse sequence may include non-uniform control pulses, non-uniform label pulses, non-uniform post labeling delay time, non-uniform background suppression pulses, non-uniform acquisition repetition time, or non-uniform acquisition flip angle.

Abstract: A magnetic resonance fingerprinting (“MRF”) framework that implements simultaneous multislice acquisition techniques with a Hadamard RF-encoding to simultaneously acquire magnetic resonance data from multiple slices simultaneously is described. As one non-limiting example, magnetic resonance data can be simultaneously acquired from four different slices. In other embodiments, however, the Hadamard encoding can be condensed into one or two acquisitions, rather than four.

Abstract: A system and method for performing magnetic resonance fingerprinting (MRF) is provided that includes performing a pulse sequence that is sensitive to field inhomogeneities to acquire a series of signal evolutions form a region of interest (ROI) of the subject to form MRF data. The method also includes varying field inhomogeneities across the ROI to acquire the series of signal evolutions, comparing the MRF data with an MRF dictionary to determine at least one tissue property of the subject in the ROI, and producing at least one map of the at least one tissue property.

Abstract: Example apparatus and methods concern determining whether a target material appears in a region experiencing nuclear magnetic resonance (NMR). One method acquires a baseline value for a magnetic resonance parameter (MRP) while the region is not exposed to a molecular imaging agent that affects the MRP and acquires a series of quantitative values for the MRP while the sample is influenced by a molecular imaging agent. Quantitative values may be acquired during a clinically relevant time period (e.g., 60 minutes) during which the change in the MRP (e.g., T1) caused by the molecular imaging agent is at least 90% of the peak change caused by the molecular imaging agent. The molecular imaging agent may be SBK2 and may produce a desired change in T1 for at least thirty minutes in glioblastoma.

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: A system and method is provided for operating a high-field magnetic resonance (MR) system includes performing a series of data acquisition modules without respiratory gating. Each data acquisition module is formed of a steady-state free precession pulse sequence. Performing the series of data acquisition modules includes varying at least one of an amplitude of an excitation pulse or a repetition time of the steady-state free precession pulse sequence between adjacent data acquisition modules in the series of data acquisition modules to acquire a series of MR data with random or pseudo-random imaging acquisition parameters. The series of MR data is compared to a dictionary of signal evolution profiles to determine a match between the series of MR data with at least one signal evolution profile in the dictionary indicating at least one quantitative parameter in the subject.

Abstract: Example apparatus and methods concern determining whether a target material appears in a region experiencing nuclear magnetic resonance. One method acquires a baseline value for a magnetic resonance parameter (MRP) while the region is not exposed to a molecular imaging agent that affects the MRP, acquiring a non-specific uptake value for the MRP while the sample is influenced by a non-specific molecular imaging agent and acquiring a specific uptake value for the MRP while the sample is influenced by a specific molecular imaging agent. The non-specific masking problem is solved by characterizing the region as a function of the baseline value, the non-specific uptake value, and the specific uptake value. The function relies on the similarities and differences between non-specific uptake of the non-specific molecular imaging agent, non-specific uptake of the specific molecular imaging agent, and specific uptake of the specific molecular imaging agent.

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 distinguishing prostate cancer tissue from normal peripheral zone tissue based on quantitative data acquired using NMR fingerprinting in combination with apparent diffusion co-efficient (ADC) values or perfusion values acquired using DWI-MRI or DCE-MRI.

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.