Abstract: A power amplifier unit for a magnetic resonance device includes at least two power amplifier modules. Symmetrical output signals from the at least two power amplifier modules are fed to a shared balun. The shared balun is provided on a printed circuit board (PCB) and is realized in a unit with the at least two power amplifier modules. The balun is configured to asymmetrize a sum signal.

Abstract: An antenna arrangement for magnetic resonance applications includes antenna elements substantially parallel to a common central axis, distributed around the central axis at a distance from the central axis, and enclosing an essentially cylindrical volume. The antenna arrangement includes intermediate connections that connect to immediately adjacent antenna elements at connection points that lie between the ends of the antenna elements. A preamplifier connects to each of the intermediate connections and has an output that, in a receive mode, corresponds to a respective feed-out point. In send mode, the antenna arrangement injects radio-frequency signals into the antenna elements using the injection points. The antenna arrangement is also configured to adjust the intermediate connections to a higher resistance when the antenna arrangement is in the send mode and at least some of the intermediate connections to a lower resistance when the antenna arrangement is in the receive mode.

Abstract: The present embodiments relates to a magnetic resonance tomography system having a coil system. The coil system includes an upper part having at least one antenna and a lower part having at least one antenna. The upper part of the coil arrangement is disposed above a bore for receiving an examination subject. The lower part of the coil arrangement is disposed below a field of view of the magnetic resonance tomography system. The lower part of the coil arrangement is closer to the examination subject than the upper part of the coil arrangement.

Abstract: The present embodiments relate to a method and a local coil arrangement for a magnetic resonance tomography system. The local coil arrangement includes an antenna element for the reception of signals from an object under examination. The local coil arrangement also includes an A/D converter for the conversion of analog signals received with the antenna element into digitized signals, and a memory configured for the storage of the digitized signals.

Abstract: A method and a facility are disclosed for imaging a PET spectrum with a PET detector, especially a PE-MR tomograph, and evaluation of the PET spectrum. To improve the correction of the base line in PET and thereby to improve the energy resolution for the PET images, at least one embodiment of the facility includes: a sampling facility for sampling the output signal of the PET detector at a predetermined sampling rate; an edge discriminator for recognizing at least one edge of a PET pulse; a background signal discriminator for estimating a background signal under the PET pulse; and an integrator device for determining the energy of the PET pulse in the PET spectrum above of the background signal from the sample values of the sampling facility.

Abstract: The present embodiments include an antenna circuit that is adapted to supply and/or read out a plurality of antenna elements of an antenna assembly of a magnetic resonance imaging system. The antenna elements are decoupled by phase shifter elements and supplied with signals by the phase shifter elements. The antenna circuit may also be used to detect signals that are received by the antenna elements.

Abstract: A magnetic resonance device with a measurement chamber, an antenna arrangement that has a plurality of antenna elements arranged at least in certain areas around the measurement chamber, a gradient coil system arranged outside the antenna arrangement as seen from the measurement chamber, and a high-frequency shield system arranged between the antenna arrangement and the gradient coil system are provided. The high-frequency shield system has a reflector array with a plurality of passive reflector resonance circuits, each of which is configured such that resonance frequencies of the plurality of passive reflector resonance circuits lie below an operating magnetic resonance frequency of the magnetic resonance device and that the plurality of passive reflector resonance circuits has an inductive overall impedance.

Abstract: Front bandpass filters that are essentially transmissive only between a minimum frequency and a maximum frequency filter the magnetic resonance signals. Front frequency mixers mix output signals of each of the bandpass filters with a front LO frequency that is standard for all the magnetic resonance signals. Rear bandpass filters that are essentially transmissive only around a front intermediate frequency filter the output signals of the front frequency mixers. Rear frequency mixers mix output signals of each of the rear bandpass filters with a respective constant rear LO frequency. Frequency filters that are transmissive for frequencies in the range of the difference of the rear LO frequency that is supplied to the rear frequency mixer arranged upstream thereof and the front intermediate frequency filter the output signals of the rear frequency mixers. Output signals of the frequency filters are combined into a common signal, which is transmitted onward.

Abstract: A wireless magnetic resonance imaging (MRI) scanner bore tube assembly has a radio frequency (RF) antenna, a microwave antenna array and an electrical screen. The RF antenna is formed of a series of RF antenna elements, each comprising a rung. The rungs are spaced at intervals of substantially half of the wavelength of the frequency of operation of the microwave antenna array. The microwave antenna array is formed by a series of microwave antenna elements interleaved between the rungs and the screen acts as a reflector to reflect signals from the microwave antenna elements towards the center of the bore tube.

Abstract: In a magnetic resonance marking system marking a flowing medium in a marking region, as well as in a magnetic resonance system with such a magnetic resonance marking system, a method to control a magnetic resonance marking system, and a method to generate magnetic resonance exposures, a radio-frequency transmission device generates marking radio-frequency signals, and a marking radio-frequency transmission coil emits the marking radio-frequency signals in the marking region. A magnetic field determination device determines a magnetic field strength in the marking region, and a control unit derives a marking transmission frequency from the determined magnetic field strength and to control the radio-frequency transmission device so that marking radio-frequency signals at the derived marking transmission frequency are emitted by the marking radio-frequency transmission coil.

Abstract: In a magnetic resonance apparatus having an RF radiating coil and gradient coils, and in a method for operating such a magnetic resonance apparatus, a pulse sequence, composed of multiple time steps, is specified for operating the gradient coils to time-dependently select regions of a selected slice of a selected volume of a subject. A non-linear equation system is then solved to obtain feed parameters for individual channels of the transmit coil for each time step, with specification of a desired target magnetization, and dependent on the pulse sequence specified for the gradient coils. The non-linear equation system is based on discrete values for time and space variable and, in addition to equations resulting from the Bloch equation, which are non-linear in their feed parameters, includes at least one additional equation that describes boundary conditions for the examination of the subject.

Abstract: In a method and a device for optimization of a combined system for the acquisition of magnetic resonance tomographic measurement data and an image reconstruction process, the image reconstruction process is already executed during the acquisition of the measurement data, by the calculation process being deconstructed into calculation packets, and rules are defined that establish which requirements must be met for the execution of the respective calculation packet. The calculation process is reorganized into a workflow structure based on the calculation packets and the rules. The calculation process is controlled using the generated workflow structure synchronized to the acquisition process. The rules entirely describe the calculation process, i.e. inclusive of all calculation packets and their logical dependencies. The stability of the calculation process is thus entirely independent of the chronological order of the measurement data acquisition.

Abstract: An arrangement for transmitting magnetic resonance signals, with a transmission link that connects a local coil with a receiver, has a first channel of the local coil with a first single antenna to acquire a first magnetic resonance signal, as well as a first mixer connected with the first single antenna. The first mixer forms an intermediate-frequency first signal from the supplied first magnetic resonance signal. A second channel of the local coil has a second single antenna to acquire a second magnetic resonance signal, as well as a second mixer connected with the second single antenna. The second mixer forms an intermediate-frequency second signal from the supplied second magnetic resonance signal. The local coil has a device for signal combination that, by frequency multiplexing, that combines the intermediate-frequency first signal of the first channel and the intermediate-frequency second signal of the second channel so that it arrives at the receiver via the transmission path.

Abstract: A magnetic resonance system has multiple individual transmission antennas each charged with a transmission current to emit an individual excitation field in an examination volume to excite magnetic resonances in a subject, producing a total excitation field as a superimposition of the individual excitation fields. A determination device provided with a spatial distribution of an absorption rate of the examination subject, determines a combination of amplitudes and phase positions for the transmission currents relative to one another such that a locally absorbed power at a first point of the examination subject relative to a locally absorbed power at a second point of the examination subject satisfies a relative condition.

Abstract: Example systems, apparatus, circuits, and so on described herein concern parallel transmission in MRI with on-coil current-mode (CMCD) amplifiers. One example apparatus includes switched voltage-mode class D (VMCD) pre-amplifiers. Another example apparatus includes amplitude modulation of the output of the CMCD amplifiers using feedback control based, at least in part, on a comparison of an envelope of transmit coil current to an envelope of an input RF pulse.

Abstract: In a magnetic resonance imaging apparatus and method, radio frequency signals are radiated into an examination subject and/or received from the examination subject by an array of radio frequency coils that completely encircles the examination subject, and that is located at a distance from the examination subject out of contact with the examination subject.

Abstract: The invention relates to a combined radiation therapy and magnetic resonance unit. For this purpose, in accordance with the invention a combined radiation therapy and magnetic resonance unit is provided comprising a magnetic resonance diagnosis part with an interior, which is limited in radial direction by a main magnet, and a radiation therapy part for the irradiation of an irradiation area within the interior, wherein at least parts of the radiation therapy part, which comprise a beam deflection arrangement, are arranged within the interior.

Abstract: An arrangement for controlling individual antennas of an antenna arrangement in a magnetic resonance apparatus has a device for signal division. This device is designed such that each transmission signal present at an input of the device for signal division is divided among all outputs of the device for signal division. Each output of the device for signal division is connected with a respective individual antenna. A number of transmission branches are provided for the inputs of the device for signal division. Each transmission branch has components that form a transmission signal that is modulated specific to the transmission branch and is amplified. Each transmission branch is connected with a respective associated input of the device for signal division, such that the transmission signal therefrom arrives at the associated input.

Abstract: In a method for processing radio frequency signals of a magnetic resonance imaging system in which the coil portion of the magnetic resonance imaging system includes a body coil and a local coil, radio frequency signals are supplied to the body coil, and these radio frequency signals are coupled to said local coil, and transmitted by said local coil into a region to be examined. A corresponding radio frequency system has a local coil and a body coil, with power coupling between the local coil and the body coil; during the phase for transmitting the radio frequency signals. The body coil serves to couple the radio frequency signals to be transmitted to the local coil, and the local coil serves to transmit the coupled radio frequency signals to a region to be examined. This method and system allow the transmitting function of the local coil to be achieved without having a coil plug on a patient bed to provide a radio frequency signal transmitting channel.

Abstract: In a magnetic resonance tomography local coil arrangement and a method for processing signals received thereby at least one local coil is fashioned to receive at least one reception signal and at least one amplifier is provided that amplifies the at least one reception signal. A frequency converter generates at least one intermediate frequency signal from the at least one reception signal the intermediate frequency of the intermediate frequency signal differing from the reception signal frequency of each reception signal. An analog-digital converter converts the analog intermediate frequency signal into a digitized signal. A shielding device shields against at least radio-frequency signals, the shielding device surrounding at least the analog-digital converter. At least one frequency filter is arranged between the at least one local coil and the analog-digital converter, the frequency filter exhibiting a transmission range for signals with the intermediate frequency of an intermediate frequency signal.