61 results about "Radiofrequency coil" patented technology

The present disclosure provides various systems and methods for magnetic resonance imaging. In one aspect, a method for magnetic resonance imaging can include receiving k-space data sets acquired by radiofrequency (RF) coils. Each of the k-space data sets can correspond to a different one of the RF coils. Each of the k-space data sets can be truncated and / or under sampled. The method can further include generating partial images of a field of view based on the k-space data sets and generating an initial image based on the partial images. The initial image can be full image of the field of view. The method can further include applying an iterative image reconstruction technique to generate an updated image based on the initial image.

The present disclosure relates to a current sensing system for a magnetic resonance imaging (MRI) scanner operating at 1H and 23Na resonant frequencies. The system includes a dual-tuned RF coil with a network of up to two parallel quarter-wavelength transmission lines, each integrated with a PIN diode-coupled shunt capacitor. A multiple half-wavelength transmission line is employed with a corresponding pair of shunt capacitors and PIN diodes. A quarter-wavelength transmission line, coupled with a power amplifier through a matching network of shunt capacitors and PIN diodes, is also included. The configuration parameters are designed to tune the system to the fundamental frequency and its first odd multiple, correlating with the 1H resonant frequency, and to the 23Na resonant frequency. The system accurately senses coil currents by detecting voltage variations in the matching network, thereby facilitating precise current measurements at the tuned resonant frequencies without the need for external sensors.

A current sensing system for a magnetic resonance imaging (MRI) scanner operating at 1H and 31P resonant frequencies includes a dual-tuned RF coil with a network of up to two parallel quarter-wavelength transmission lines, each integrated with a PIN diode-coupled shunt capacitor. A multiple half-wavelength transmission line is employed with a corresponding pair of shunt capacitors and PIN diodes. A quarter-wavelength transmission line, coupled with a power amplifier through a matching network of shunt capacitors and PIN diodes, is also included. The configuration parameters are designed to tune the system to the fundamental frequency and its first odd multiple, correlating with the 1H resonant frequency, and to the 31P resonant frequency. The system accurately senses coil currents by detecting voltage variations in the matching network, thereby facilitating precise current measurements at the tuned resonant frequencies without the need for external sensors.

In an RF coil according to the present disclosure, a first outer peripheral region formed by a plurality of elements of a first fixing belt, which is disposed on a top plate on which a subject is placed, has a tapered shape as being spaced from a first end side of the top plate, a second outer peripheral region formed by a plurality of elements of a second fixing belt, which is disposed on the top plate, has a tapered shape as being spaced from a second end side of the top plate, and the first outer peripheral region and the second outer peripheral region are disposed with phases in a longitudinal direction shifted from each other.

To provide an RF coil, a bed device, and a magnetic resonance imaging device capable of preventing reduction of SNR regardless of the body shape of a subject, facilitating setting, and improving a workflow.SOLUTION: An RF coil according to the present disclosure is configured so that a first outer shell region which is formed of multiple elements of a first fixing belt arranged on a top plate where a subject is placed has a tapered shape as it is separated from a first end side of the top plate, and a second outer shell region which is formed of multiple elements of a second fixing belt arranged on the top plate has a tapered shape as it is separated from a second end side of the top plate. The first outer shell region and the second outer shell region are positioned so that their phases in a longitudinal direction are offset from each other.SELECTED DRAWING: Figure 6

NMR-based lithium measuring and monitoring downhole tools and methods measure at least one lithium concentration of a fluid in a borehole and / or a surrounding formation of the borehole, wherein the downhole tool has an NMR sensor having a magnet-coil geometry with at least one magnet and a RF coil tuned to match a Larmor frequency of a nucleus of lithium. The downhole tools and methods acquire an NMR-based lithium concentration measurement of a fluid at a sensitive region within the wellbore and / or formation that is defined by the magnet-coil geometry of the NMR sensor and determine a lithium concentration of the fluid at the sensitive region based on the acquired NMR-based lithium concentration measurement. The downhole tools and methods may interpret an acquired signal based on relaxation distributions of total acquired signals, wherein the acquired signal is indicative of the acquired NMR-based lithium concentration measurement and separate a lithium signal from confounding signals deriving from other non-lithium nuclei based on the interpretated acquired signal.

Systems and methods are provided for a graphical user interface (GUI) for a magnetic resonance imaging (MRI) system. In an example, a system includes a display device; one or more processors; and memory storing instructions executable by the one or more processors to: determine a connection status for each of a plurality of ports, each port of the plurality of ports configured to couple a radiofrequency (RF) coil to an MRI apparatus; generate a GUI that includes a port status indicator for each port, each port status indicator having a visual appearance that is based on that port's connection status; and output the GUI for display on the display device.

An optically controlled, multi-transmitter magnetic resonance imaging system for multi-nuclear, high field applications is disclosed. In one embodiment, the MRI system may include a dual-tuned radio-frequency (RF), on-coil power amplifier for amplifying RF power signals at two or more frequencies for the multi-nuclear excitations for use in a dual-tuned coil MRI device or a nested coil MRI device. In one particular implementation, the dual-tuned amplifier of the MRI system may receive optical carrier signals through the broadband optical interface to control the on-coil amplifiers. A variable effective inductor circuit for use in tuning the dual-tuned amplifier is also disclosed. The variable effective inductor circuit includes a gallium nitride (eGaN) field effect transistor (FET) device connected to an inductor. The inductance of the variable effective inductor circuit can be adjusted by modulating a drain-source voltage of the eGaN FET device controlled based on a pulse duration of an optical carrier signal.

To provide an RF coil array capable of obtaining relatively high sensitivity in subjects of various sizes.SOLUTION: An RF coil array according to the present disclosure includes a first coil unit including a first securing belt made of a first stretch material stretchable in a first direction and a plurality of RF coils disposed independently on the first securing belt, and a second coil unit including a second securing belt made of a second stretch material stretchable in the first direction and a plurality of RF coils disposed independently on the second securing belt. The first coil unit is attached to the subject with the distal end of the first fixing belt directed from one side to the other side in the first direction of the subject, and the second coil unit is attached to the subject with the distal end of the second fixing belt directed from the other side to the one side in the first direction of the subject such that at least a part of the second fixing belt overlaps the first coil unit.SELECTED DRAWING: Figure 7

Described herein are compact MRI systems having (i) an open, field-cycling magnet configured to produce and cycle between a first and second non-uniform B0 different from the first non-uniform B0, and (ii) a second component configured to produce a nonlinear spatial encoding gradient. Importantly, the open, field-cycling magnet and the spatial encoding gradients are customized to a specific imaging application. In particular, the second component contains one or several nonlinear DC gradient coils for spatial encoding. It also contains one or several a radiofrequency coils geometrically configured to have a non-planar configuration. Lastly, both the RF coils and DC encoding gradients are tailored specifically to the first non-uniform B0 magnetic field, the second non-uniform B0 magnetic field, or both. Artificial intelligence models trained to read imaging data can be incorporated as a component of the MRI systems. Also described are methods of using the disclosed MRI systems.

A high-frequency coil device can maintain a distance between coils at any mounting position in an RF coil including a movable coil unit and can achieve a uniform sensitivity distribution and high sensitivity. A first coil unit configured to move along a substantially circular trajectory and a second coil unit fixed within the substantially circular trajectory are provided, the first coil unit and the second coil unit are disposed at substantially point-symmetric positions, and magnetic coupling between conductor loops provided in both the coil units is maintained substantially constant in a movable range of the first coil unit.

The invention provides a six-axis portable magnetic resonance imaging system and a magnetic resonance imaging method, and relates to the technical field of magnetic resonance imaging, the system comprises a mobile base, a six-axis mechanical arm, an annular magnetic head assembly, a wearable radio frequency coil and a processing assembly; the annular magnetic head assembly is detachably connected to the execution tail end of the six-axis mechanical arm. The annular magnetic head assembly comprises a first framework, an electromagnetic compensation coil, a gradient coil, an annular magnetic field sensor array and a Halbach magnetic ring array, and the electromagnetic compensation coil, the gradient coil, the annular magnetic field sensor array and the Halbach magnetic ring array are arranged on the first framework. The processing assembly is used for acquiring monitoring information of the imaging area monitored by the magnetic field sensor array and pre-processing the monitoring information, inputting the pre-processed monitoring information into a neural network model pre-trained by adopting historical magnetic field characteristics, and controlling compensation current on the electromagnetic compensation coil according to information output by the neural network model; and generating a target magnetic resonance image according to the acquired magnetic resonance signal. The invention provides a portable magnetic resonance imaging system which is high in examination flexibility.

Various systems and methods for magnetic resonance imaging are provided. In one aspect, a method for magnetic resonance imaging may include receiving a k-space data set acquired by a radio frequency (RF) coil. Each of the k-space datasets may correspond to a different one of the RF coils. Each of the k-space data sets may be truncated and / or undersampled. The method may further include generating a local image of the field of view based on the k-space data set and generating an initial image based on the local image. The initial image may be a full view of the field of view. The method may further include applying an iterative image reconstruction technique to generate an updated image based on the initial image.

The invention relates to an open-close type radio frequency coil structure for neck and limb joint magnetic resonance imaging and a design method, and belongs to the technical field of nuclear magnetic resonance. The coil structure adopts a separated design, and comprises a first radio frequency coil part and a second radio frequency coil part which can move relatively, and a connecting mechanism for connecting the two parts. According to the structural design, the coil can be conveniently opened and closed, so that a patient can conveniently put parts such as necks or joints of four limbs which are inconvenient to move into the coil for magnetic resonance imaging. In addition, the invention further provides a design method of the open-close type radio frequency coil, according to the method, a boundary element and stream function combined method is adopted, optimization design can be carried out according to the special shape of a to-be-detected part, and therefore the filling factor and the signal-to-noise ratio of the coil are improved, and then a magnetic resonance image with higher quality is obtained.

Embodiments of the present disclosure provide a magnetic resonance device and a radiofrequency coil thereof. The radiofrequency coil includes at least one coil portion. Each of the at least one coil portion includes one or more flexible protective layers and one or more flexible coil units. The one or more flexible coil units are disposed on the one or more flexible protective layers and used to receive a magnetic resonance (MR) signal of an object. The at least one coil portion includes a first array and a second array, the first array being configured to be disposed about a first part of the object with a first curvature, the second array being configured to be disposed about a second part of the object with a second curvature, or form a hyperbolic surface structure.

A testing unit for the non-destructive testing of an electrically conductive and / or ferromagnetic workpiece comprises at least one magnetizing coil (1) and at least one RF coil (2), wherein the magnetizing coil (1) is configured to generate a static or quasi-static magnetic field. The RF coil, acting as a transmitting coil (4), is configured to generate an alternating magnetic field oriented perpendicular to the static or quasi-static magnetic field, wherein the RF coil (2) and the magnetizing coil (1) can be arranged one above the other in a direction perpendicular to the surface of the workpiece.This allows an acoustic transmission signal to be generated by superimposing the signals of the transmitting coil (4) and the signals of the magnetizing coil (1) and to be introduced into the workpiece in a measuring position (3), wherein the RF coil (2) is designed as a receiving coil (5) to receive an acoustic response signal in the measuring position (3).

An NMR probe head (10'), designed for insertion into an MR apparatus (101), comprising a probe head housing (4) for receiving a cylindrical temperature control tube (2) made of thermally conductive material surrounding a sample (5), a heat exchanger (1) being mounted at the axial end of which is in thermal contact with the temperature control tube and projecting radially from the latter onto the inner wall of the probe head housing, and a first insulation element (3) made of poorly thermally conductive material surrounding the temperature control tube at an axial distance from the heat exchanger and comprising an RF coil (6), is characterized in that at least one temperature control element (7) made of thermally conductive material is positioned radially between the first insulation element and the inner wall of the probe head housing for heat distribution along the z-axis.which completely surrounds the first insulation element azimuthally and extends axially along the z-axis at least over the full axial length of the first insulation element. This minimizes the temperature gradient across the sample in both axial and radial directions.

An RF coil assembly for an MRI system may include a coil support and an RF coil. The coil support may include a base, a first adjusting arm and a second adjusting arm. The first adjusting arm is rotatably connected to the base and rotatable about a first axis relative to the base. The second adjusting arm is rotatably connected to the first adjusting arm and rotatable about a second axis relative to the first adjusting arm, the second axis being parallel to the first axis. The RF coil is rotatably connected to the second adjusting arm and rotatable about a third axis relative to the second adjusting arm, the third axis being parallel to the first axis. The position and angle of the RF coil can be flexibly adjusted so that the RF coil fits the examination subject more closely, thus helping to increase imaging quality.

In some embodiments, the present disclosure relates to a radio frequency (RF) surface coil for a magnetic resonance imaging (MRI) system. The RF surface coil includes a rigid lower member, at least one flexible upper member mechanically coupled to the rigid lower member, and one or more RF coil elements housed by the rigid lower member and the at least one flexible upper member. The at least one flexible upper member is dimensioned and manipulable to substantially conform the one or more RF coil elements to a portion of a patient anatomy to be imaged by the MRI system.

A Magnetic Resonance Imaging (MRI) scan method and an MRI system are provided in the present disclosure. The method may include generating a first hydrogen nucleus image of an object using a Radio Frequency (RF) coil of the MRI system, and further include identifying at least one coil identification of at least one multi-nucleus coil in the first hydrogen nucleus image. The at least one multi-nucleus oil is placed on body surface of the object. The method may also include determining an imaging range of the at least one multi-nucleus coil based on the at least one identified coil identification in the first hydrogen nucleus image, and determining whether to generate a multi-nucleus image of the object using the at least one multi-nucleus phased-array coil based on the imaging range of the at least one multi-nucleus oil and a Region Of Interest (ROI) on the first hydrogen nucleus image.

Methods, systems, and apparatus for causing changes to cells or tissue within or adjacent to an eye. The system includes an external RF coil configured to transmit RF signals. The system also includes a wearable device configured to be removably disposed on the eye, the wearable device including a plurality of internal radiofrequency (RF) coils configured to receive the RF signals from the external RF coil and a plurality of stimulating electrodes configured to electromagnetically stimulate a portion of the eye or an area adjacent to the eye, causing changes to cells or tissue within or adjacent to the eye.

Described herein are compact breast MRI systems having (i) an open, field-cycling magnet configured to produce and cycle between a first and second non-uniform B0 different from the first non-uniform B0, and (ii) a second component configured to produce a nonlinear spatial encoding gradient. Importantly, the open, field-cycling magnet and the spatial encoding gradients are customized to a specific imaging application. In particular, the second component contains one or several nonlinear DC gradient coils for spatial encoding. It also contains one or several a radiofrequency coils geometrically configured to have a non-planar configuration. Lastly, both the RF coils and DC encoding gradients are tailored specifically to the first non-uniform B0 magnetic field, the second non-uniform B0 magnetic field, or both. Artificial intelligence models trained to read imaging data can be incorporated as a component of the MRI systems. Also described are methods of using the disclosed breast MRI systems.

The objective is to provide an RF coil device, which can be attached to a subject used in an environment with a magnetic field, that allows for position adjustment while the subject is moved inside the mounting device. [Solution] The RF coil device of the embodiment is an RF coil device that receives electromagnetic waves emitted from a subject in response to an RF pulse irradiated onto the subject under the influence of a magnetic field, and comprises a plurality of RF coil elements, a holding mechanism, and an outer casing. The plurality of RF coil elements are arranged in a planar manner. A non-conductive fluid flows into or out of the holding mechanism from a fluid path. The outer casing houses the plurality of RF coil elements and the holding mechanism. Each of the RF coil elements is positioned on the surface of the outer casing on the side that the outer casing contacts the subject, and the holding mechanism is positioned on the surface of the outer casing on the side opposite to the side that the outer casing contacts the subject.

An incubator includes a patient compartment, a support structure, a patient table coupled to the support structure, an RF coil selectively coupled to the support structure, the RF coil including a receiver arranged along a peripheral edge of the RF coil, and a hood selectively coupled to one of the support structure or the patient table and configured to engage the receiver. When the hood is engaged with the receiver a volume of the hood and a volume of the RF coil merge together.

The invention provides a rat caudal vertebra magnetic resonance image acquisition device and method, and the device comprises a nuclear magnetic resonance spectrometer, a fixing material, and an elimination filling material. The fixing material is fixed at the bottom of a scanning radio frequency coil of the nuclear magnetic resonance spectrometer, a groove is formed in the fixing material, and the groove is matched with the caudal vertebra and the hip of a rat to be detected in position; the elimination filling material is an adaptive material, the elimination filling material and the fixing material fix the position of the to-be-detected rat, and a magnetic resonance image is obtained through scanning of a nuclear magnetic resonance spectrometer. The fixing material used in the invention has certain plasticity, can effectively fill irregular space around a scanning area, reduces magnetic sensitive artifacts, and improves the imaging definition. The rat caudal vertebra scanning device is simple in structure, free of filling materials, non-toxic, odorless, high in plasticity, light in texture and moderate in viscosity, can stabilize the caudal vertebra scanning area of a rat to be detected, does not cause extra burden to animals, ensures that the position of the rat is fixed in the imaging process, and ensures the accuracy of images.

NMR-based lithium measuring and monitoring downhole tools and methods measure at least one lithium concentration of a fluid in a borehole and / or a surrounding formation of the borehole, wherein the downhole tool has an NMR sensor having a magnet-coil geometry with at least one magnet and a RF coil tuned to match a Larmor frequency of a nucleus of lithium. The downhole tools and methods acquire an NMR-based lithium concentration measurement of a fluid at a sensitive region within the wellbore and / or formation that is defined by the magnet-coil geometry of the NMR sensor and determine a lithium concentration of the fluid at the sensitive region based on the acquired NMR-based lithium concentration measurement. The downhole tools and methods may interpret an acquired signal based on relaxation distributions of total acquired signals, wherein the acquired signal is indicative of the acquired NMR-based lithium concentration measurement and separate a lithium signal from confounding signals deriving from other non-lithium nuclei based on the interpretated acquired signal.

This invention provides a method and apparatus for detecting ionization, and an ion beam etching device. It utilizes a probe to acquire and detect the voltage of an RF supply device to obtain a detection signal. The RF supply device provides an RF signal to the quartz barrel and may include an RF power source and an RF coil. The detection point for detecting the RF supply device is located between the RF power source and the RF coil. If the detection signal is a sine wave, it indicates that there is no ionization outside the quartz barrel connected to the RF supply device. If the detection signal has harmonics or distorted waves in addition to the sine wave, it indicates leakage current, thus confirming the presence of ionization outside the quartz barrel connected to the RF supply device. This allows for the detection of ionization by the RF supply device, enabling timely detection of ionization events outside the quartz barrel and allowing for timely responses to such external ionization. Therefore, it allows for more precise control of the etching process.

The invention discloses a passive large-aperture magnetic resonance metamaterial with stable gain, and relates to the technical field of magnetic resonance imaging, the passive large-aperture magnetic resonance metamaterial comprises a body, the body comprises a plurality of coil assemblies distributed at intervals in the circumferential direction, the plurality of coil assemblies are in central symmetry about the central point of the body, and the adjacent coil assemblies are connected through metal wires; each coil assembly comprises two spiral coils with opposite spiral directions, and the two spiral coils are distributed at intervals in the circumferential direction and the outer ends of the two spiral coils are connected. The passive large-aperture magnetic resonance metamaterial with stable gain, provided by the invention, can be effectively applied to an MRI (Magnetic Resonance Imaging) system required by a large-aperture imaging target, keeps the gain stable when being multiplexed with a radio frequency coil, effectively focuses a magnetic field in a region of interest, and improves the signal-to-noise ratio of magnetic resonance imaging.

A hydrogen-fluorine dual-resonance radiofrequency (RF) coil for a rectum includes a support pillar, where the support pillar is provided with a first conductive tape, a second conductive tape, a third conductive tape, and a fourth conductive tape; at one end of the support pillar, the first conductive tape and the second conductive tape are connected through a resistor R1, and the third conductive tape and the fourth conductive tape are connected through a capacitor C1; the capacitor C1 is provided with an excitation port; the excitation port is connected to a dual tuning and matching circuit; at the other end of the support pillar, the first conductive tape and the third conductive tape are connected through a resistor R2, and the second conductive tape and the fourth conductive tape are connected through a resistor R3; a middle portion of each of the conductive tapes is provided with an opening.

Devices and methods are provided for non-invasive sensing of tissue fluid distribution in a patient. The device includes one or more magnets configured to provide a static magnetic field source; one or more RF transmitter coils connected to a pulse sequence generator which are configured to apply a varying magnetic field to tissues of the patient; one or more RF receiver coils configured to detect a magnetic field generated within tissues of the patient; and a signal acquisition and processor system configured to acquire signals from the RF receiver coils and perform an NMR measurement of a relaxation parameter of hydrogen nuclei within a muscle tissue site of the patient. A single-sided MR sensor device may include permanent magnets arranged in a unilateral linear Halbach array; and RF coils and a processor which are configured to produce a depth-resolved, diffusion-weighted, multicomponent T2 relaxometry measurements of intramuscular fluid shifts in a patient.