G01R33/5659

System and method for magnetic resonance imaging

The disclosure relates to a system and method for correcting inhomogeneity in an MRI image. The method may include the steps of: acquiring a first set of k-space data, acquiring a second set of k-space data, generating the convolution kernel of the first set of k-space data based on the first set of k-space data and the second set of k-space data, performing inverse Fourier transform on the convolution kernel of the first set of k-space data to obtain an inversely transformed convolution kernel of the first set of k-space data, and generating a corrector based on the inversely transformed convolution kernel of the first set of k-space data. The method may be implemented on a machine including at least one processor and storage.

B0 AND B1 CORRECTION ANTI-RESPECTIVELY
20210389404 · 2021-12-16 · ·

The disclosure relates to techniques for perming chemical exchange saturation transfer (CEST) imaging correction. The present disclosure improves the speed of correcting CEST images.

MRI scanner with active interference suppression and interference suppression method for an MRI scanner

An MRI scanner and a method for operation of the MRI scanner are provided. The MRI scanner has a first receiving antenna for receiving a magnetic resonance signal from a patient in a patient tunnel, a second receiving antenna for receiving a signal having the Larmor frequency of the magnetic resonance signal, and a receiver. The second receiving antenna is located outside of the patient tunnel or near an opening thereof. The receiver has a signal connection to the first receiving antenna and the second receiving antenna and is configured to suppress an interference signal by the second receiving antenna in the magnetic resonance signal received by the first receiving antenna.

RF MAGNETIC FIELD HOMOGENEITY AND MAGNETIC RESONANCE IMAGE UNIFORMITY USING INDUCTIVE COUPLING

An apparatus, method, and system are disclosed for improving uniformity of RF magnetic field in an MRI system, and thereby improving both signal-to-noise ratio and uniformity of imaging sensitivity across a sampling volume, to provide more uniform MRI images. A passive LC resonator develops induced EMF and induced currents in a primary RF magnetic field; the secondary magnetic field produced thereby can counteract magnetic field amplitude gradients to produce a more homogeneous RF magnetic field. In systems with separate transmit and receive coils, a shunt detuning circuit is pulsed ON to prevent interference during the transmit period. In a dual-frequency MRI machine (e.g. 19F and 1H), the RF magnetic field at the lower operating frequency can be homogenized by tuning the resonance of the passive resonator between the two operating frequencies. Another resonator can improve RF field uniformity at the higher operating frequency. Variants and experimental results are disclosed.

Active b1+ shimming of transmission coils

The invention provides for a magnetic resonance imaging system (100) comprising a radio frequency system (116, 114, 118) configured for acquiring magnetic resonance data (144) from an imaging zone (108). The radio frequency system is configured for sending and receiving radio frequency signals to acquire the magnetic resonance data, wherein the radio frequency system comprises: an elliptical transmission coil (114) configured for generating a B1+ excitation field within the imaging zone; and an active B1 shim coil (118) configured for being placed within the imaging zone, wherein the radio frequency system is configured for suppling radio frequency power to the active B1 shim coil during the generation of the B1+ excitation field by the elliptical transmission coil, wherein the B1 shim coil is configured for shimming the B1+ excitation field within the imaging zone.

MAGNETIC RESONANCE IMAGE PROCESSING METHOD AND DEVICE, AND COMPUTER READABLE STORAGE MEDIUM
20220206097 · 2022-06-30 ·

Provided in embodiments of the present invention are a magnetic resonance image processing method and device, and a computer-readable storage medium. The method includes: determining a central angle; converting, on the basis of the central angle, a radio-frequency field pattern of a radio-frequency transmitting coil into an angular pattern; acquiring, on the basis of a trigonometric function value of the angular pattern, a radio-frequency transmitting field pattern of the radio-frequency transmitting coil; and correcting, on the basis of the radio-frequency transmitting field pattern, a magnetic resonance image to be corrected.

ULTRATHIN RECONFIGURABLE METAMATERIAL FOR SIGNAL ENHANCEMENT OF MAGNETIC RESONANCE IMAGING
20220206089 · 2022-06-30 ·

A reconfigurable metamaterial is used to enhance the reception field of a radio frequency (“RF”) coil for use in magnetic resonance imaging (“MRI”). In general, the metamaterial can be a metasurface, which may be flexible, having a periodic array of resonators. Each resonator in the periodic array can be defined as a unit cell of the metamaterial and/or metasurface. The unit cells include a first conductor and a second conductor separated by an insulator layer. The first conductor can be a solid conductor and the second conductor can be a conductive fluid (e.g., a liquid metal, a liquid metal alloy) contained within a microfluidic channel. Varying the volume of conductive fluid in each unit cell adjust the signal enhancement ratio of the metamaterial.

Portable magnetic resonance imaging methods and apparatus

According to some aspects, a portable magnetic resonance imaging system is provided, comprising a magnetics system having a plurality of magnetics components configured to produce magnetic fields for performing magnetic resonance imaging. The magnetics system comprises a permanent B.sub.0 magnet configured to produce a B.sub.0 field for the magnetic resonance imaging system, and a plurality of gradient coils configured to, when operated, generate magnetic fields to provide spatial encoding of emitted magnetic resonance signals, a power system comprising one or more power components configured to provide power to the magnetics system to operate the magnetic resonance imaging system to perform image acquisition, and a base that supports the magnetics system and houses the power system, the base comprising at least one conveyance mechanism allowing the portable magnetic resonance imaging system to be transported to different locations. According to some aspects, the base has a maximum horizontal dimension of less than or equal to approximately 50 inches. According to some aspects, the portable magnetic resonance imaging system weighs less than 1,500 pounds. According to some aspects, the portable magnetic resonance imaging system has a 5-Gauss line that has a maximum dimension of less than or equal to five feet.

MAGNETIC RESONANCE TOMOGRAPHY WITH SIMULATION-BASED INTERFERENCE REDUCTION
20220187397 · 2022-06-16 ·

An MR sequence for an object is simulated by a computing unit in order to determine a simulation signal relating to a course of a transverse magnetization of nuclear spins. Depending on the simulation signal, a resting period of the MR sequence is determined during which an expected MR signal amplitude is always less than or equal to a predetermined limit value. An MR recording is carried out in accordance with the MR sequence, wherein an analysis signal is received in each case by a main receiving antenna and at least one auxiliary receiving antenna during an analysis period corresponding to the resting period and at least one interference suppression parameter is determined in dependence on the analysis signals. An MR signal is received by the main receiving antenna and an interference signal is received in each case by the at least one auxiliary receiving antenna. An interference-suppressed MR signal is generated based on the MR signal, the interference signals and the at least one interference suppression parameter.

METHOD AND SYSTEM FOR CONTROLLING A MAGNETIC RESONANCE IMAGING SYSTEM

A method for controlling a magnetic resonance imaging system, including: selecting a plurality of spatially non-selective initial RF-pulses each having a predefined pulse shape and a predefined frequency; determining a combined RF-pulse from the initial RF-pulses by choosing a time-offset comprising a relative application time-shift between the initial RF-pulses, wherein this time-offset is chosen such that the initial RF-pulses overlap; and including the combined RF pulse in a pulse sequence applied in a magnetic resonance imaging system.