Patent classifications
G01R33/34092
Ferromagnetic frame for magnetic resonance imaging
An apparatus for providing a B.sub.0 magnetic field for a magnetic resonance imaging system. The apparatus includes at least one permanent B.sub.0 magnet to contribute a magnetic field to the B.sub.0 magnetic field for the MRI system and a ferromagnetic frame configured to capture and direct at least some of the magnetic field generated by the B.sub.0 magnet. The ferromagnetic frame includes a first plate configured to support the at least one permanent B.sub.0 magnet and a first post attached to the first plate using a first connection assembly, wherein the first connection assembly includes a first connector that connects the first post and the first plate and a second connector attached to the first connector.
Local coil apparatus for magnetic resonance imaging
A local coil apparatus for performing a magnetic resonance (MR) scanning on a local part of a subject is provided. The local coil apparatus may include at least one receiving system for receiving the local part. The at least one receiving system may each include an activation member, a receiving member assembly, and a driving mechanism. The receiving member assembly may include one or more receiving members. Each of the one or more receiving members may include a first coil assembly configured to receive MR signals during the MR scanning. The driving mechanism may be physically connected to the one or more receiving members. When the local part is placed on the activation member, the activation member may cause the driving mechanism to drive the receiving member assembly to change from a first configuration to a second configuration to reduce a distance between at least a portion of the first coil assembly and a portion of the local part so that the first coil assembly conforms to the local part.
SYSTEMS AND METHODS FOR ESTIMATING MAGNETIC SUSCEPTIBILITY THROUGH CONTINUOUS MOTION IN AN MRI SCANNER
Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.
Solid sample magnetic coupling high resolution nuclear magnetic resolution probe and method of use
In various embodiments of the invention, a solid sample magic angle spinning nuclear magnetic resonance (NMR) probe can utilize an appropriate inductance parent coil with a fixed capacitor and introducing an idler coil with a variable capacitor which can inductively couple to the parent coil by adjusting the variable capacitance of the idler coil. By coupling the idler coil to the parent coil in this manner a double resonance circuit can be provided without the disadvantages of prior art coils. In an alternative embodiment of the invention, a solid sample magic angle spinning nuclear magnetic resonance probe can utilize an appropriate inductance parent coil with a fixed capacitor, introducing an idler coil with a variable capacitor in a first region and two variable inductor coupling coils and two coupling coils in a second region, where the two variable inductors are connected to the parent coil to reduce the number of coils in the sample region of the NMR probe, where variable inductors can inductively couple to the parent coil by adjusting one or both the capacitance of the variable capacitor of the idler coil and/or adjusting the variable inductors to observe a tuned condition between the parent coil and the idler coil.
Carrier phase tracking using multiple carriers
A clocked electronic device, such as a wireless magnetic resonance (MR) receive coil (20), comprises a wireless receiver or transceiver (30) configured to receive a propagation-delayed wireless clock synchronization signal (54) comprising first and second propagation-delayed carrier signals at respective first and second carrier frequencies separated by a frequency difference, a clock (60) comprising a local oscillator (62) driving a digital counter (64), and at least one electronic signal processing component (66) configured to perform clock synchronization. This includes determining a wrap count (k) from a phase difference (φ.sub.1) between phases of the first and second propagation-delayed carrier signals, unwrapping a wrapped phase (φ.sub.2,wrapped) of the propagation-delayed wireless clock synchronization signal using the wrap count to generate an unwrapped phase (φ.sub.2,wrapped), and synchronizing the clock using the unwrapped phase.
Provision of position information of a local RF coil
A computer-implemented method for provision of a result dataset having position information of a local radio-frequency coil, including: providing input data having at least magnetic resonance data, which is acquired by means of the local radio-frequency coil; determining a result dataset by applying a trained function to the input data, wherein the result dataset comprises position information for determining the position of the local radio-frequency coil; and providing the result dataset.
Slotted waveguide array RF coil for magnetic resonance systems
The exemplary system and method facilitate excitation of RF magnetic fields in ultra-high field (UHF) magnetic resonance (MRI) systems (e.g., MRI/NMR system) using a slotted waveguide array (SWGA) as an exciter coil. The exemplary exciter coil, in some embodiments, is configurable to provide RF magnetic field B.sub.1.sup.+ with high field-uniformity, with high efficiency, with excellent circular polarization, with negligible axial z-component, with arbitrary large field of view, and with exceptional possibilities for field-optimizations via RF shimming.
MINIATURIZED NMR TOOL ELECTRONICS
An NMR well logging tool is provided that includes a sensor and associated electronic circuitry. The sensor includes an array of RF antenna elements. The electronic circuitry includes at least one low-power integrated circuit and a plurality of high-power modules corresponding the RF antenna elements of the array. Each high-power module is coupled to a corresponding RF antenna element of the array and includes an RF amplifier that is configured to amplify RF pulses generated by the at least one low-power integrated circuit and supplied thereto for transmission by the corresponding antenna element. In embodiments, the RF amplifier of each high-power module can include an H-bridge circuit or other suitable RF amplifier.
Methods and systems for determining fluid content in formation samples using low field nuclear magnetic resonance
Methods and systems for determining fluid content in a formation sample are disclosed. The method includes disposing the formation sample with a standard sample of a known chemical composition and one or more nuclear magnetic resonance (NMR) attributes in a NMR coil or probe, and acquiring NMR signals for the formation sample and the standard sample simultaneously. The system includes a NMR probe or NMR coil, a formation sample, and a standard sample with known chemical composition and one or more nuclear magnetic resonance (NMR) attributes, wherein the formation sample and the standard sample are disposed in the NMR coil or probe, and wherein NMR signals are acquired for the formation sample and the standard sample simultaneously.
Methods for measuring the porosity of core samples using NMR analysis
A method for determining the porosity of a core sample can include: submerging a core sample in a NMR saturation fluid, wherein the core sample has a permeability of 10 mD or less; exposing the fluid to a vacuum while the core sample is submerged the NMR saturation fluid for a sufficient period of time to saturate the core sample; removing the vacuum while maintaining the core sample submerged the NMR saturation fluid; taking a NMR measurement of fluids in the core sample; and determining a porosity of the core sample based on a correlation between the NMR measurement and a NMR signal to fluid volume calibration.