A flexible resonant trap circuit is provided that includes a transmission line arranged to include a helical winding that has a first helical winding segment and a second helical winding segment; and a capacitor coupled between the first and second helical winding segments.

Provided in the present invention are a power control apparatus for a radio-frequency power amplifier and a radio-frequency transmission system for a magnetic resonance imaging system. The power control apparatus comprises: a power control module used to receive a control voltage so as to control an output power of the radio-frequency power amplifier; a voltage detection module used to detect an operating voltage provided to the radio-frequency power amplifier and to output a detected voltage; and a voltage adjustment module used to adjust, on the basis of the detected voltage, the control voltage received by the power control module so as to adjust the output power of the radio-frequency power amplifier.

The present disclosure relates to techniques for the selection of one or more measuring coils in magnetic resonance imaging. Herein, account can be taken of a preselection in the selection of the one or more measuring coils from a plurality of candidate coils.

The present disclosure relates to techniques for the selection of one or more measuring coils in magnetic resonance imaging. Herein, account can be taken of a preselection in the selection of the one or more measuring coils from a plurality of candidate coils.

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.

Embodiments described herein relate to detectors and their method of use for sensing electromagnetic fields, electromagnetic signals, biochemical analytes, and/or other conditions in subjects. The device may include an inductively-coupled implantable coil-based transducer that converts electrical, photonic, biochemical signals, and/or other appropriate signals and/or conditions originating in tissues and/or transplanted tissue grafts into changes in a property of the transducer, such as a resonance frequency, that may be detected using an alternating magnetic field that may be provided by a magnetic resonance imaging (MRI) signal and/or other appropriate source. In some embodiments, the detector comprises a FET that changes state upon detection of a subject condition of interest. The change in the FET may change the resonance frequency of an associated LC or RLC circuit. The change in resonance frequency may change the brightness and/or intensity of the detector when detected by an MRI scanner or other appropriate scanner.

Embodiments relate to MRI RF multi-tune coil elements, arrays, and MRI systems comprising such elements. One example embodiment comprises: a LC coil comprising one or more matching points; and two or more matching branches, each of which connected to the LC coil at matching point of the one or more matching points that is associated with that matching branch, wherein each matching branch comprises an associated set of one or more RF traps configured to block each frequency of two or more frequencies other than a frequency associated with that matching branch, and wherein each matching branch is configured to match to an associated predetermined impedance at the frequency associated with that matching branch.

A magnetic resonance imaging apparatus includes a T/R switch. The T/R switch includes a double sided microstripline based hybrid couplers with a top side and a bottom side each including two concentric microstripline based hybrid couplers. Each of the two concentric microstripline based hybrid couplers includes an inner microstripline based hybrid coupler and an outer microstripline based hybrid coupler. The inner microstripline based hybrid coupler forms an inner loop of the two concentric microstripline based hybrid couplers and the outer microstripline based hybrid coupler forms an outer loop. In a transmission mode, the inner microstripline based hybrid coupler and the outer microstripline based hybrid coupler at the top side of the dual-tuned T/R switch are activated. In a receiving mode the inner microstripline based hybrid coupler and the outer microstripline based hybrid coupler at the top side and at the bottom side of the dual-tuned T/R switch are activated.

A coil decoupling method for a magnetic resonance imaging device, including: sending an instruction causing a transmitter to send a transmitted signal, acquiring a received signal received by a receiver, wherein the received signal is a signal arriving at the receiver after the transmitted signal passes through two coils to be adjusted of a plurality of coils, determining the coupling value between the two coils to be adjusted based on the transmitted signal and the received signal, and sending an instruction for adjusting a decoupling component based on the coupling value.

It is an object of the invention to provide a radio frequency (RF) transmit—receive coil (1) for a magnetic resonance (MR) imaging system with an integrated vital signs detector (3) for the detection of vital signs of a patient within the magnetic resonance (MR) imaging system, whereby contact sensors directly attached to the body of the patient, are replaced by a contactless system for monitoring vital signs, which makes it much easier to measure vital signs of the patient. The object is achieved by a RF transmit-receive coil (1) comprising a vital signs detector (3) wherein the vital signs detector (3) is integrated in the RF transmit-receive coil (1), wherein a pair of electrically conducting coil elements (4) of the RF transmit-receive coil (1) forms the vital signs detector (3), wherein the vital signs detector (3) is a capacitive vital signs detector (3), the capacitive vital signs detector (3) being adapted for receiving capacitive vital signs signals. The present invention also concerns a system for the detection of vital signs of a patient within a magnetic resonance (MR) imaging system, a method for operating the system for the detection of vital signs of a patient within a magnetic resonance (MR) imaging system, a software package for a magnetic resonance (MR) imaging system and a software package for upgrading a magnetic resonance (MR) imaging system.