An MRI apparatus according to an embodiment includes a whole body RF coil accommodated in a gantry. The whole body RF coil includes a first element unit used for transmission of a radio frequency magnetic field; and a second element unit used for reception of a magnetic resonance signal produced from a subject having been applied with the radio frequency magnetic field. The first element unit is a birdcage-type RF coil having two end rings and a plurality of rungs spaced apart from each other along the circumferential direction of the end rings. The second element unit is a microstrip antenna.

A local coil, a magnetic resonance tomography scanner, a system including local coil and magnetic resonance tomography scanner, and a method for operating the system are provided. The local coil has an active detuning facility and a passive detuning facility with substantially separate circuits. The magnetic resonance tomography scanner includes a local coil actuation for actuating the active detuning facility and a local coil monitoring for the detuning facilities, which likewise have substantially separate circuits.

A radio frequency (RF) circuit is provided for use with a magnetic resonance imaging (MRI) scanner to transmit an RF receive signal to an amplifier circuit, the RF circuit comprising: a transmission line; an antenna electrically connected to a first end portion of the transmission line; an impedance transformation circuit; an impedance matching and detuning circuit electrically connected between the transmission line and the impedance transformation circuit, wherein the impedance matching and detuning circuit includes: multiple reactive impedance elements; and two or more switches operable to controllably switch between configuring the multiple reactive impedance elements to cause matching of overall impedance of the RF circuit to a prescribed input impedance seen at the amplifier circuit at a prescribed RF frequency during a receive mode of the MRI scanner, and to cause an increase of impedance at the antenna, to reduce sensitivity of the antenna to RF signals at the prescribed frequency during an excitation mode of the MRI scanner.

A magnetic resonance coil and a magnetic resonance imaging system using the same are provided. The magnetic resonance coil may include an antenna, an amplifier, and a protective circuit. The antenna may be configured to receive a radio frequency (RF) signal emitted from an object. The antenna may not resonate with the RF signal. The amplifier operably coupled to the antenna configured to amplify the RF signal. The protective circuit may be configured to protect the antenna and the amplifier.

A flexible radiofrequency receiving coil array. The flexible radiofrequency receiving coil array is provided on a flexible panel and comprises several rows of coil units. Adjacent two rows of coil units in the several rows of coil units are alternately arranged. Preamplifiers are provided in the coil units. In the flexible radiofrequency receiving coil array, two preamplifiers in adjacent two coil units are provided on a same preamplifier mounting plate on the flexible panel, where multiple preamplifier mounting plates are provided on the flexible panel, and the preamplifier mounting plates of different columns and rows are linearly arranged. The flexible radiofrequency receiving coil array effectively reduces the distribution density of the preamplifiers, ensures the flexibility and maximum degree of distension of the coil array, and improves the fit of the coil array to the human body, thus increasing image signal-to-noise ration and image quality.

A coil for receiving a magnetic resonance signal is provided. The coil may include a first conductor; and a second conductor electrically coupled to the first conductor. The second conductor may extend along the first conductor. The first conductor may have at least one first opening or the second conductor may have at least one second opening. The first conductor and the second conductor may be electrically coupled using an electronic component placed at the at least one first opening or the at least one second opening so that an electric current flows between the first conductor and the second conductor through the electronic component.

Various embodiments of the present disclosure are directed to a magnetic resonance imaging (MRI) radio frequency (RF) coil comprising a current-control circuit. A conductive trace forms a coil inductor and comprises a first trace segment and a second trace segment separated by the current-control circuit, which comprises a first reactive element and a circuit branch. The first reactive element is electrically coupled from the first trace segment to the second trace segment, and the circuit branch is electrically coupled in parallel with the first reactive element. The circuit branch comprises a second reactive element and a sub-circuit branch electrically coupled in parallel. The sub-circuit branch comprises a third reactive element and an electronic switch (e.g., a PIN diode) electrically coupled in series. The first reactive element and the third reactive element are one of capacitive and inductive, and the second reactive element is another one of capacitive and inductive.

A system/device, such as a gradiometer probe for detecting RF signals, or for example for explosive detection, has the shape of the coils in its adjustment mechanism that minimizes the cross-talk between the receiver probe (Rx) and the transmitting antenna (Tx) in such a way as to minimize (or reduce) the areas where the distance between the coils during the adjustment is the smallest. Moving coils along the plain of the coils is one mechanism of achieving it. Having the coils of different shapes, e.g., circular receiver and oval transmitter coils, is another. Many shapes are possible, including circular, oval, elliptical, and polygonal, to give a few examples. In some embodiments both of these methods/approaches are combined in a single device.

A magnetic resonance coil and a magnetic resonance imaging system using the same are provided. The magnetic resonance coil may include an antenna, an amplifier, and a protective circuit. The antenna may be configured to receive a radio frequency (RF) signal emitted from an object. The antenna may not resonate with the RF signal. The amplifier operably coupled to the antenna configured to amplify the RF signal. The protective circuit may be configured to protect the antenna and the amplifier.

An NMR measurement apparatus includes a transmitting antenna including a transmitter coil, a capacitor, a dissipating component and a restricting component, and a receiving antenna physically separated from the transmitting antenna. A processor is configured to apply a drive signal at a first voltage level to generate a transmission signal having a selected transmission frequency, where the receiving antenna is deactivated during generation, connect the dissipating component to the transmitter coil to dissipate stored energy in the transmitter coil, connect the restricting component to the transmitter coil to restrict the transmitting antenna to a second voltage level smaller than the first voltage level and based on a voltage of NMR signals from the sensitive volume, activate the receiving antenna and detect a NMR signal, where the restricting component is connected to the transmitter coil and restricts the transmitting antenna during the activating and the detecting.