Abstract:
Methods and a device for automatic detuning of a magnetic resonance tomography (MRT) local coil not connected to an MRT system are provided. The device has self-closing switches that are closed or open, depending on the presence of an MRT high-frequency field.
Abstract:
A transmission antenna apparatus is provided to emit transmission magnetic fields in magnetic resonance imaging scanners. The transmission antenna apparatus includes at least a first flat antenna and a second flat antenna. The first flat antenna is arranged in relation to the second flat antenna in such a way that first areas, formed in the planar extent of partial structures of the first flat antenna in each case situated in the same plane, are opposite to second areas, formed in the planar extent of partial structures of the second flat antenna in each case situated in the same plane, in a manner mirrored in a mirror plane. The first flat antenna and the second flat antenna, as part of the structure thereof, share a first path, situated on the mirror plane, over the full length of the path. The magnetic resonance imaging scanner has such a transmission antenna apparatus.
Abstract:
The transmission antenna apparatus is configured for emitting transmission magnetic fields in magnetic resonance imaging devices and includes one or more flat antennas. A magnetic resonance imaging device includes such a transmission antenna apparatus.
Abstract:
A magnetic resonance apparatus includes receive coils and a receiver device for processing magnetic resonance signals received by coil elements of the receive coils. The receive coils are subdivided into at least a first group having at least one receive coil and a second group having at least one receive coil. The receive coils of the first group are connected to the receiver device via a hardwired communications link, and the receive coils of the second group are each connectable or connected to the receiver device via a wireless communications link.
Abstract:
A system for electromagnetic excitation of an object under examination during magnetic resonance tomography includes a radio frequency (RF) device for generating a radio-frequency signal and a plurality of antennas for emitting the radio-frequency signal. A signal connection exists between the output of the RF device and the plurality of antennas. A source impedance of the signal connection to the output of the RF device at a connection point of the plurality of antennas is significantly higher than the impedance of the plurality of antennas at the connection points, so that the plurality of antennas are fed in a current source feed mode if a radio-frequency signal is present.
Abstract:
A radio-frequency acquisition device for a magnetic resonance tomography apparatus has at least one reception antenna for acquisition of magnetic resonance signals and with an amplifier device to amplify acquired magnetic resonance signals. The amplifier device has an input transistor and a transformation device to transform the source impedance of the acquisition antenna into a source impedance adapted to the input transistor, and wherein the transformation device can be switched between at least two transformation ratios.
Abstract:
A magnetic resonance apparatus includes receive coils and a receiver device for processing magnetic resonance signals received by coil elements of the receive coils. The receive coils are subdivided into at least a first group having at least one receive coil and a second group having at least one receive coil. The receive coils of the first group are connected to the receiver device via a hardwired communications link, and the receive coils of the second group are each connectable or connected to the receiver device via a wireless communications link.
Abstract:
A system for electromagnetic excitation of an object under examination during magnetic resonance tomography includes a radio frequency (RF) device for generating a radio-frequency signal and a plurality of antennas for emitting the radio-frequency signal. A signal connection exists between the output of the RF device and the plurality of antennas. A source impedance of the signal connection to the output of the RF device at a connection point of the plurality of antennas is significantly higher than the impedance of the plurality of antennas at the connection points, so that the plurality of antennas are fed in a current source feed mode if a radio-frequency signal is present.
Abstract:
A magnetic resonance (MR) local coil system includes local MR transmit coils that may be inductively coupled to at least one power-feed coil of an MR device. At least two local MR transmit coils may be used to generate local B1 excitation fields that are differently structured with respect to each other.
Abstract:
Methods and a device for automatic detuning of a magnetic resonance tomography (MRT) local coil not connected to an MRT system are provided. The device has self-closing switches that are closed or open, depending on the presence of an MRT high-frequency field.