Abstract: A magnetic resonance apparatus, for acquiring magnetic resonance data from a person who is asleep, includes a person support apparatus to provide a sleeping place; an acquisition arrangement including a radiofrequency coil arrangement for transmitting excitation pulses and for receiving magnetic resonance signals; and a controller, designed to operate the acquisition arrangement according to a magnetic resonance sequence for acquiring a magnetic resonance dataset from a region under examination of the person. The magnetic resonance apparatus includes a main magnetic field of strength less than 20 mT, in particular less than 10 mT, and the controller includes an acquisition unit for acquiring a magnetic resonance dataset via a prolonged magnetic resonance sequence having a total acquisition duration of more than one hour.

Abstract: In a method for compensating stray magnetic fields in a magnetic resonance imaging system with two or more examination areas: a value for a predefined first magnetic field to be applied in a first examination area, in addition to a basic magnetic field is provided; information defining a predefined sequence control pulse to be applied in a second examination area is provided; a stray magnetic field in the second examination area resulting from application of the first magnetic field in the first examination area is determined; a compensated sequence control pulse for the second examination area is calculated from the predefined sequence control pulse and the determined stray magnetic field; and the compensated sequence control pulse is applied to the second examination area.

Abstract: A line for an electrical connection in a magnetic resonance tomography apparatus and a magnetic resonance tomography apparatus with a corresponding line are provided. The line includes an electrical interference conductor that may pick up an electromagnetic interference signal from an environment and/or irradiate the electromagnetic interference signal into the environment. The line also includes a sensor that is electrically and/or magnetically coupled to the interference line.

Abstract: A magnet assembly for magnetic resonance imaging is used to generate the basic magnetic field with a strength needed to produce the steady state or equilibrium position of nuclei or nuclear spins in magnetic resonance imaging. This magnet, or a part thereof, is vibrated or tilted or otherwise periodically moved so as to change its position and thereby generate a time-varying gradient field, which is used to enter the acquired magnetic resonance signals as raw data into k-space.

Abstract: In a magnetic resonance apparatus and a method for operation thereof, at least one electrical operating value of at least one predetermined component of the apparatus is captured and, as a function of the at least one operating value, at least one coil operating value of a transmitting coil arrangement of the magnetic resonance apparatus is controlled for the purpose of limiting a B1 value.

Abstract: In a method and a magnetic resonance apparatus for generating movement information relating to an examination region of a patient, a reception circuit is provided that receives MR signals within a reception frequency range. An electromagnetic signal is generated that has a first frequency that is outside the reception frequency range of the reception circuit, and that interacts with at least some of the examination region, so the electromagnetic signal undergoes a modification. A modulated signal based on the modified first signal is generated that has a frequency within the reception frequency range. The modulated signal is transmitted to the reception circuit, and is forwarded to a computer, wherein movement information is determined based on the modulated signal.

Abstract: A device for generating wideband signals in a local coil and a magnetic resonance tomography system with the device are provided. The device has a first analog-digital converter for digitizing a magnetic resonance signal, a signal conditioner, a pulse filter, and a transmit antenna. The signal conditioner is configured to increase a harmonic component in an output signal of the first analog-digital converter, and the pulse filter is configured to restrict an output signal of the signal conditioner to a predetermined frequency band before the output signal of the signal conditioner is emitted via the transmit antenna. The receiver is configured to receive and digitize the signal via a receive antenna, and regain a digital representation of the magnetic resonance signal by a signal processor.

Abstract: Techniques are disclosed for a local coil and a magnetic resonance imaging system. The local coil includes a plurality of coil units that respectively receive magnetic resonance signals generated when magnetic resonance detection is performed on a detected object, and a signal processing unit configured to perform processing including signal preprocessing and quadrature modulation on the magnetic resonance signals received by the plurality of coil units to obtain signals to be transmitted. Contactless connectors are also disclosed, each being configured to couple the signals to be transmitted to a contactless connector at the MR system side.

Abstract: A calibration method for calibrating a measuring element for determining an electric current flowing through a basic-field magnet of a magnetic resonance imaging system includes performing a measurement with the measuring element, and performing a frequency measurement in the magnetic field of the basic-field magnet with a frequency measuring unit. The measurement of the measuring element and the frequency measurement are corresponding to the same magnetic field of the basic-field magnet. The calibration method also includes calculating a calibration factor based on a deviation between the measurement with the measuring element and the frequency measurement, and calibrating the measuring element or the electric current in the basic-field magnet based on the calibration factor.

Abstract: A radio-frequency system for a magnetic resonance apparatus has a local coil, a body coil, and an impedance adjusting shield. The body coil is wirelessly power-coupled with the local coil such that the body coil serves as a transmitting coil for radio-frequency signals and the local coil serves as a receiving coil for magnetic resonance signals. The local coil is disposed in an internal cavity of the impedance adjusting shield. An impedance of the local coil is adjusted by the impedance adjusting shield so as to match the impedance of the local coil and the body coil. The impedance adjusting shield has a frequency modulation element that adjusts the resonance frequency of the local coil. The body coil couples power to the local coil, and the impedance adjusting shield effectively reduces energy transmission efficiency loss caused by reflection, thereby improving energy transmission efficiency.

Abstract: A basic field magnet arrangement for a magnetic resonance tomography system can include a plurality of basic field magnet segments spatially separated from one another, each being configured to generate an intended magnetic field having a defined segment main field direction. At least two basic magnet segments of the plurality of the basic field magnet segments are arranged relative to one another such that the respective segment main field directions of their intended magnetic fields extend at a deflection angle to one another such that the intended magnetic fields of the at least two basic field magnet segments produce an intended basic magnetic field. The intended basic magnetic field including a basic magnet main field direction can have a ring-shaped profile.

Abstract: A magnetic resonance scanner has a base, a C-arm mounted on the base, the C-arm having an inner surface curved in a C-shape, the C-shape defining a plane, a magnet mounted on the inner curved surface of the C-arm, the magnet generating a basic magnetic field for magnetic resonance imaging, and a drive mechanism mechanically connected to the magnet. The drive mechanism rotates the magnet around an axis that is orthogonal to the plane so as to selectively position the magnet in at least two magnet positions that are respectively above and beneath a patient, who is situated in the C-arm along or parallel to the axis.

Abstract: An apparatus and a method for spatial encoding in magnetic resonance tomography using a radio frequency signal are provided. A first set of parameters from a first frequency and from a first amplitude, and from a second frequency and a second amplitude is determined by the magnetic resonance tomograph, and corresponding signals are generated by a radio frequency device and transmitted by an antenna apparatus. A first gradient above the Larmor frequency of the nuclear spins is generated by the Bloch-Siegert effect. The same thing ensues with a second set of parameters that differs from the first set of parameters at least in one frequency or amplitude and therefore generates a second, different gradient.

Abstract: A method for correcting a B0 inhomogeneity in a magnetic resonance scan with a magnetic resonance tomograph is provided. The magnetic resonance tomograph includes a controller, a radio frequency unit, and a transmitting antenna. In the method, the controller determines a transmission signal that is suitable for correcting an effect of an inhomogeneity of a static B0 magnetic field in an examination volume by the Bloch-Siegert effect. The transmission signal is emitted into the examination volume.

Abstract: A single-stage radio frequency amplifier is provided with a signal amplification stage for a magnetic resonance tomography scanner, for example as a low-noise preamplifier in a local coil. The radio frequency amplifier includes a signal input, a signal amplifier, a signal output of the signal amplifier and a phase shifter. The phase shifter is in signal connection with the signal output and the signal input of the signal amplifier and is configured to couple a predetermined portion of an output signal of the signal amplifier with a predetermined phase shift into the signal input of the signal amplifier.

Abstract: A magnetic resonance scanner has a base, a C-arm mounted on said base, the C-arm having an inner surface curved in a C-shape, the C-shape defining a plane, a magnet mounted on said inner curved surface of said C-arm, the magnet generating a basic magnetic field for magnetic resonance imaging, and a drive mechanism mechanically connected to the magnet. The drive mechanism rotates the magnet around an axis that is orthogonal to said plane so as to selectively position said magnet in at least two magnet positions that are respectively above and beneath a patient, who is situated in the C-arm along or parallel to the axis.

Abstract: A magnet assembly for magnetic resonance imaging is used to generate the basic magnetic field with a strength needed to produce the steady state or equilibrium position of nuclei or nuclear spins in magnetic resonance imaging. This magnet, or a part thereof, is vibrated or tilted or otherwise periodically moved so as to change its position and thereby generate a time-varying gradient field, which is used to enter the acquired magnetic resonance signals as raw data into k-space.

Abstract: System and methods are provided for a passive transmitting antenna for a magnetic resonance tomography system and to a system including a passive transmitting antenna and magnetic resonance tomography system and a method for operation. The passive transmitting antenna includes a tuning apparatus with a tuning element. The tuning apparatus is configured to perform a tuning of the passive transmitting antenna as a function of a relative position of the passive transmitting antenna in a patient tunnel of the magnetic resonance tomography system.

Abstract: The disclosure relates to a field camera and a method for measuring a magnetic field distribution using a magnetic resonance tomograph and the field camera. The field camera has a number of samples, which are distributed over a spatial volume to be measured, and a number of receive antennas. In an act of the method, a sensitivity matrix for the receive antennas, for each sample at each receive antenna, is captured using the magnetic resonance tomograph. In another act, antenna signals of the samples in a magnetic field to be measured are captured by the receive antennas, using the magnetic resonance tomograph. Finally, magnetic resonance signals of the individual samples are determined from the antenna signals as a function of the sensitivity matrix, using a controller. In a further act, the magnetic field strength at the location of the samples may be determined from the magnetic resonance signals.

Abstract: The invention relates to an MRI scanner and a method for operation of said MRI scanner. The MRI scanner has a first receiving antenna for receiving a magnetic resonance signal from a patient in a patient tunnel, a second receiving antenna for receiving a signal having the Larmor frequency of the magnetic resonance signal, and a receiver. The second receiving antenna is located outside of the patient tunnel or near an opening thereof. The receiver has a signal connection to the first receiving antenna and the second receiving antenna and is designed to suppress an interference signal by the second receiving antenna in the magnetic resonance signal received by the first receiving antenna.