Patent application number | Description | Published |
20120235678 | NUCLEAR MAGNETIC RESONANCE (NMR) FINGERPRINTING - 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. | 09-20-2012 |
20120262165 | RELAXOMETRY - Apparatus, methods, and other embodiments associated with multi-scale orthogonal matching pursuit (OMP) for magnetic resonance imaging (MRI) relaxometry are described. One example method includes controlling a nuclear magnetic resonance (NMR) apparatus to cause selected nuclei in an item to resonate by applying radio frequency (RF) energy to the item and then acquiring multiple series of magnetic resonance (MR) images of the item, the series of MR images having different scales. The example method includes controlling the NMR apparatus to produce a combined signal evolution from a first signal evolution associated with a first series of MR images and a second signal evolution associated with a second series of MR images and to characterize relaxation of the selected nuclei in the item as a function of an OMP that compares the combined signal evolution to a set of combined comparative signal evolutions. | 10-18-2012 |
20120262166 | COMBINED CORRELATION PARAMETER ANALYSIS - 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. | 10-18-2012 |
20120268123 | RELAXOMETRY QUANTIFICATION SELF-JUSTIFICATION FITTING - Apparatus, methods, and other embodiments associated with self-justification fitting for magnetic resonance imaging (MRI) relaxation parameter quantification are described. One example nuclear magnetic resonance (NMR) apparatus includes a self-justification fitting logic configured to selectively include and exclude data points from a set of data points associated with NMR signals based, at least in part, on their impact on a fit attribute (e.g., standard deviation). In one embodiment, the self-justification is configured to select a subset of data points from the set of data points as a function of values for a fit attribute computed from fitting at least two different subsets of data points from the set of data points to a known NMR signal evolution. | 10-25-2012 |
20130265047 | Nuclear Magnetic Resonance (NMR) Fingerprinting - 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, and a characterization logic configured to characterize a resonant species in the object as a result of comparing acquired signals to reference signals. | 10-10-2013 |
20130271126 | Wireless Magnetic Field Monitoring In Magnetic Resonance Imaging - Apparatus, methods, and other embodiments associated with wireless magnetic field monitoring (wMFM) in magnetic resonance imaging (MRI) are described. One example apparatus includes a wMFM module configured to receive an MFM signal from an MFM probe and to wirelessly transmit modulated MFM signals produced from the received MFM signals to an MRI apparatus. The MRI apparatus is configured with a wireless receiver that receives and processes the modulated MFM signals into information used in an image reconstruction. The MRI apparatus includes an MRI reconstruction logic configured to produce an MR image from the MRI signal based, at least in part, on the magnetic field measurement information. | 10-17-2013 |
20130271128 | Multi-slice Blipped TrueFISP-CAIPIRINHA - Apparatus, methods, and other embodiments associated with multi-slice blipped TrueFISP-CAIPIRINHA in magnetic resonance imaging (MRI) are described. One example apparatus produces CAIPIRINHA phase cycling in a TrueFISP-CAIPRINHA pulse sequence using a blipped gradient pattern rather than using radio frequency (RE) pulses. The phase cycling is produced by controlling a gradient coil in an MRI apparatus to produce a pre-scan pulse that is configured to set magnetization into a steady state position and then controlling the gradient coil to produce a balanced alternating phase pulse per repetition (TR). The balanced alternating phase pulse is configured to introduce a CAIPIRINHA aliasing pattern between slices. Controlling the gradient coil includes selectively adding and removing a finite gradient area, from de-phase pulses and re-phase pulses in the pulse sequence. | 10-17-2013 |
20130271131 | Varying Blipped Trajectory - Apparatus, methods, and other embodiments associated with magnetic resonance imaging (MRI) blipped trajectories having varying blip amplitudes are described. One example method includes controlling an MRI apparatus to produce a set of blipped trajectories including a first blipped trajectory having a first blip amplitude and a second, different blipped trajectory having a second, different blip amplitude. The blip amplitudes may be based on a relationship between a trajectory and a reference. The relationship may be, for example, a rotation angle. The rotation angle may be a proxy for information including a gradient trajectory speed associated with a blipped trajectory or an amount of unused gradient energy available while producing the blipped trajectory. The blip amplitudes may be selected to produce incoherent sampling during an MRI acquisition that uses the blipped trajectories. In one example, readout directions may be altered between trajectories to reduce regularity in k-space. | 10-17-2013 |
20130271137 | Magnetic Resonance Trajectory Correcting - 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. | 10-17-2013 |
20130271140 | Ordering Projections For Magnetic Resonance - Example apparatus and methods order projections in a 3D MRI acquisition to achieve improved equidistant spacing or to achieve improved adherence to a target distribution. The equidistant or target spacing may exist in k-space and/or in kt-space. In one embodiment, the improved equidistant spacing is a substantially uniform spacing. The substantially uniform spacing may be achieved using a modification of a charge repulsion analysis that treats points of projections that intersect the surface of a 3D volume to be imaged as point charges distributed on the 3D volume. In another embodiment, the target spacing may be uniform, non-uniform, uniform in parts and non-uniform in other parts, and other combinations. | 10-17-2013 |
20140015527 | Through-Time GRAPPA - 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. | 01-16-2014 |
20140103924 | Heteronuclear Nuclear Magnetic Resonance Fingerprinting - Apparatus, methods, and other embodiments associated with heteronuclear nuclear magnetic resonance fingerprinting (NMRfp) are described. One example apparatus includes individually controllable radio frequency transmission coils configured to apply varying NMRfp RF excitations to a sample. The NMR apparatus may apply excitations in parallel. The excitations cause different nuclei to produce different signal evolutions. Different pairs of nuclei may produce different signal evolutions depending on quantum correlations between the types of nuclei. | 04-17-2014 |
20140167754 | Magnetic Resonance Fingerprinting (MRF) With Echo Splitting - Apparatus, methods, and other embodiments associated with nuclear magnetic resonance (NMR) fingerprinting using echo splitting are described. One example 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 the number of echo splitting pulses, spacings between echo splitting pulses, flip angle of echo splitting pulses, 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, and a characterization logic configured to characterize a resonant species in the object as a result of comparing acquired signals to reference signals. | 06-19-2014 |
20140176135 | Multiturn MRI Coils In Combination With Current Mode Class D Amplifiers - Example systems, apparatus, and circuits described herein concern a multi-turn transmit surface coil used in parallel transmission in high field MRI. One example apparatus includes a balun network that produces out-of-phase signals that are amplified to drive current-mode class-D (CMCD) field effect transistors (FETs) that are connected by a coil that includes an LC (inductance-capacitance) leg. The LC leg selectively alters the output analog RF signal and the analog RF signal is used in high field parallel magnetic resonance imaging (MRI) transmission. The multi-turn transmit surface coil produces an improved (e.g., stronger) B1 field without increasing heat dissipation. | 06-26-2014 |
20140194715 | Glucose Analyzing Blood Examiner - In one embodiment, a miniaturized wearable nuclear magnetic resonance (NMR) apparatus is described. The example NMR apparatus accesses data (e.g., table, mathematical expression) that describes a relation between a nuclear magnetic resonance (NMR) signal decay rate and a known concentration of glucose in a fluid. The NMR apparatus acquires, non-invasively and in-vivo, an observed NMR signal decay rate from a fluid in a patient, and estimates a concentration of glucose in the fluid in the patient by comparing the observed NMR signal decay rate with the data that describes the relation between the NMR signal decay rate and the known concentration of glucose. The data may be generic to a population and a class of devices or may be customized to an individual patient and an individual device. | 07-10-2014 |
20140232399 | Nuclear Magnetic Resonance (NMR) Fingerprinting - 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. | 08-21-2014 |
20140266199 | Nuclear Magnetic Resonance (NMR) Fingerprinting - 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. | 09-18-2014 |
20140292324 | Fiber Optic Telemetry For Switched-Mode Current-Source Amplifier In Magnetic Resonance Imaging (MRI) - Example systems, apparatus, circuits, and other embodiments described herein concern acquiring telemetry data from an MR system and providing the telemetry data via fiber optic cable. One example apparatus includes a telemetry signal acquisition element (e.g., circuit, circuit component) that is configured to acquire a telemetry signal from a component in the MR apparatus. The component may be, for example, a transmit coil or an on-coil amplifier. The example apparatus also includes a fiber optic cable that is configured to carry an output signal from the MR apparatus through a field produced by the MR apparatus. The example apparatus also includes a telemetry signal output element that is configured to produce the output signal from the telemetry signal and to transmit the output signal via the fiber optic cable. | 10-02-2014 |
20140292327 | Magnetic Resonance Imaging With Switched-Mode Current-Source Amplifier Having Gallium Nitride Field Effect Transistors For Parallel Transmission in MRI - Example systems, apparatus, circuits, and other embodiments described herein concern parallel transmission in MRI. One example apparatus includes at least two enhanced mode gallium nitride (eGaN) based field effect transistors (FETs) that are connected by a coil that includes an LC (inductance-capacitance) leg. The apparatus includes a controller that inputs a signal to the eGaN FETs to control the production of an output analog radio frequency (RF) signal. The LC leg selectively alters the output analog RF signal. The analog RF signal is used in parallel magnetic resonance imaging (MRI) transmission. One embodiment provides an MRI transmit coil with switched-mode current-source amplification provided by a gallium nitride FET. | 10-02-2014 |
20140292328 | Magnetic Resonance Imaging (MRI) With Dual Agent Characterization - 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. | 10-02-2014 |
20140292330 | Quantifying Magnetic Resonance Parameters - Example apparatus and methods provide improved spatial and temporal resolution over conventional magnetic resonance imaging (MRI) for a large (e.g., 500 cm | 10-02-2014 |
20140294734 | Magnetic Resonance Imaging (MRI) Based Quantitative Kidney Perfusion Analysis - 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. Greater precision is achieved for estimates of the perfusion parameter or filtration parameter as a result of the quantization performed on data acquired with greater spatial resolution and temporal resolution. | 10-02-2014 |
20140296700 | Magnetic Resonance Imaging (MRI) Based Quantitative Liver Perfusion Analysis - 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. | 10-02-2014 |
20140296702 | Magnetic Resonance Imaging (MRI) With Self-Navigation and Self-Registration - 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. | 10-02-2014 |
20150070012 | Magnetic Resonance Fingerprinting Exams With Optimized Sound - Apparatus, methods, and other embodiments associated with optimizing sounds produced during nuclear magnetic resonance (NMR) fingerprinting are described. One example NMR apparatus includes an NMR logic to repetitively and variably sample a (k, t, E) space associated with a patient 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 parameters are varied in different acquisition blocks to facilitate matching sounds produced in response to the acquisition blocks to a desired set of sounds. The desired set of sounds may be a musical piece. | 03-12-2015 |