G01R33/3628

MRI SYSTEMS AND RF TRANSMIT ANTENNA ARRANGEMENTS

An MRI system RF transmit antenna arrangement 3 including an antenna 5 including a length of coaxial cable 51 with an electrically conductive core 52 and an electrically conductive outer shield 53 through which the core runs, with the core having a feed point 52a arranged for electrical connection to an RF source and at least one break 53a being provided in the electrically conductive outer shield partway along the length of coaxial cable so as to divide the electrically conductive outer shield 53 into at least two axially spaced shield portions such that at least one of the shield portions acts as a radiating element when an RF source is connected to the feed point 52a.

Self-decoupled RF coil array for MRI

A self-decoupled RF coil and method for adjusting the same is disclosed. The RF coil is an array of elements including at least one loop. Electromagnetic coupling between elements in the array causes an induced current in the at least one loop. The induced current has two modes. A reactance inserted in the at least one loop balances the two modes. The balanced current modes cancel. This cancelation results in self-decoupling of at the least one loop from the other elements in the RF coil array.

FET switch as detune circuit for MRI RF coils
09720060 · 2017-08-01 · ·

A radio frequency (RF) coil assembly for use in magnetic resonance includes a radio frequency coil (42, 100) and an electronic switch (28) which switches between open and closed states to detune and tune the coil to a preselected resonance frequency. Each electronic switch includes at least one field effect transistor (FET) (70) and a bias network (72).

SMALL FORM FACTOR IN VIVO NMR BIOMETRIC MONITOR
20170325710 · 2017-11-16 ·

Methods and apparatus for determining at least one metabolic state of a subject using a nuclear magnetic resonance (NMR) monitoring device. The NMR monitoring device comprises at least one magnet configured to generate a primary magnetic field, a transceiver coil arranged within the primary magnetic field, wherein the transceiver coil is configured to apply a time series of radiofrequency (RF) pulses to a portion of a subject located within the primary magnetic field and detect an NMR signal generated in response to application of the time series of RF pulses, and an NMR spectrometer communicatively coupled to the transceiver coil. The NMR spectrometer is configured to process the detected NMR signal to determine at least one metabolic state of the subject.

METHOD AND APPARATUS FOR ACQUIRING MAGNETIC RESONANCE DATA
20170261586 · 2017-09-14 · ·

In a method and apparatus for acquiring magnetic resonance data from a slice package composed of multiple measured slices as a target volume by executing a measuring sequence, prior to each scan of one of the measured slices, the measuring sequence includes a preparation pulse associated with the measured slice for signal suppression of a type of saturation molecule. This said preparation pulse acts on the entire target volume, and a pulse parameter of the preparation pulse is chosen for a measured slice group, composed of at least one measured slice, as a function of resonance information on the contiguous partial volume covered by the measured slice group. The pulse frequency and/or the pulse bandwidth are chosen as pulse parameters as a function of resonance information describing at least the resonance frequencies of the type of saturation molecule and a type of target molecule, the magnetic resonance data of which is to be acquired, in the contiguous partial volume of the target volume that covers the measured slice group.

Magnetic resonance coil, device and system

The embodiments relate to a magnetic resonance coil for a magnetic resonance device with a measuring chamber for an examination object and a cylindrical birdcage antenna arrangement having a plurality of antenna elements disposed at least in some areas around a measuring chamber in the form of circumferential antenna rings or axial outer rods connecting the rings. The antenna elements include electric components, e.g., reactive capacitive and/or inductive systems. The magnetic resonance coil also has at least two antenna feeds, e.g., phase-offset in relation to one another by 90°, by which radio-frequency energy is able to be supplied to the birdcage antenna arrangement. The antenna feeds include at least one symmetrical feed via at least one of the electric components of the birdcage antenna arrangement as well is at least one assigned asymmetrical feed between the birdcage antenna arrangement and a screen connection.

RADIO FREQUENCY COIL FOR MAGNETIC RESONANCE IMAGING
20220229133 · 2022-07-21 ·

A radio frequency (RF) coil apparatus is described herein for facilitating imaging of a patient positioned within a magnetic resonance imaging (MRI) system, the MRI system comprising a B.sub.0 magnet. The apparatus may comprise a frame comprising a first plate and a second plate disposed opposite the first plate; and an RF transmit coil comprising a plurality of conductors connected in series, the plurality of conductors being would around the frame and forming a plurality of turns. According to some aspects, there is provided an MRI system configured to image a patient positioned within the MRI system, the MRI system comprises a Bo magnet that produces a B.sub.0 magnetic field and the RF coil apparatus.

SYSTEMS AND METHODS FOR MAGNETIC RESONANCE IMAGING

The present disclosure provides a magnetic resonance imaging (MRI) radio frequency (RF) coil assembly. The MRI RF coil assembly may include one or more coils and one or more control circuits. Each of the one or more coils may include a first end and a second end. Each of the one or more control circuits may electrically connect the first end and the second end of one of the one or more coil. Each of the one or more control circuits may be configured to adjust an operation of the coil that is electrically connected with the control circuit based on an input control signal. The one or more control circuits may be located at different regions.

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.

Single layer magnetic resonance imaging (MRI) transmit/receive (Tx/Rx) radio frequency (RF) coil with induced current failsafe protection

A single-layer magnetic resonance imaging (MRI) radio frequency (RF) coil element configured to operate in a transmit (Tx) mode and a receive (Rx) mode, the coil element comprising: an LC coil and a failsafe circuit electrically connected with the LC coil, where the LC coil, upon resonating with a primary coil of an MRI system, generates a local amplified Tx field based on an induced current generated in the LC coil by inductive coupling between the LC coil and the primary coil, where the failsafe circuit provides, upon injection of a forward DC bias current into the failsafe circuit, a first impedance, and upon the absence of the forward DC bias current, a second, higher impedance; where the failsafe circuit, upon the single-layer MRI RF coil array element being disconnected from an MRI system, provides the second, higher impedance, and reduces the magnitude of the induced current.