Abstract: In a method to correct a signal phase in the acquisition of MR signals of an examination subject in a slice multiplexing method, in which MR signals from at least two different slices of the examination subject are detected simultaneously in the acquisition of the MR signals, a linear correction phase in the slice selection direction is determined for each of the at least two slices. An RF excitation pulse with a slice-specific frequency is radiated in each of the at least two different slices. A slice selection gradient is activated during a slice selection time period, during which the different RF excitation pulses are radiated in the at least two different slices, and the slice selection time period has a middle point in time in the middle of the slice selection time period, and the different RF excitation pulses temporally overlap for the at least two different slices.

Abstract: An arrangement includes a superconducting split ring resonator, a cryostat, and a copper coil. The resonator is arranged in the cryostat and includes at least one ring-shaped conductor made of a superconducting material and including an opening and a taper. The copper coil may be used to transmit a MRI excitation signal. This signal causes a current to be induced in the conductor that leads to the breakdown of the superconductivity. The conductor is detuned and therefore no longer develops an interfering effect. It is possible for the effect of the breakdown of superconductivity to be used for detuning in a targeted manner. After the transmission is complete, the conductor returns into the superconducting state and acts as a superconducting reception antenna for the MRI measurement signal. The copper coil is inductively coupled to the conductor and configured to read out the signal induced in the conductor.

Abstract: The embodiments relate to signal selection devices for reception antennas. The signal selection device includes a plurality of signal inputs for the reception of signals from the reception antennas via an interface arrangement, and a plurality of signal outputs for the output of altered signals from the reception antennas. The signal selection device is used for selecting/reducing received signals from the reception antennas and forwarding them to an image processing device. The signal selection device contains a plurality of A/D converter chips, a plurality of digital selection chips, and at least physical and/or logical portions of a control unit. The received signals from the reception antennas are fed into the plurality of A/D converter chips via a plurality of signal inputs, are converted into digital data streams, and are supplied to the digital selection chips via signal outputs of the A/D converter chips.

Abstract: A phantom calibration body (12) for calibrating diffusion MRI device (16) that mimics a material such as a mammalian tissue is disclosed. The phantom calibration body (12) includes a homogeneous aqueous solution (30) that contains a mixture of low molecular-weight and high molecular-weight polymers housed in a container (14) that is placed in the diffusion MRI device (16) for obtaining one or more diffusion MRI images of the phantom calibration body (12). A measure of diffusivity is calculated for each of the one or more diffusion MRI images in order to calibrate the diffusion MRI device. Methods of using the phantom calibration body (12) to calibrate diffusion MRI device (16) are also disclosed.

Abstract: Systems and methods for rapidly ramping the magnetic field of a superconducting magnet, such as a superconducting magnet adapted for use in a magnetic resonance imaging system, are provided. The magnetic field can be rapidly ramped up or down by changing the current density in the superconducting magnet while monitoring and controlling the superconducting magnet's temperature to remain below a transition temperature. A superconducting switch is used to connect the superconducting magnet and a power supply in a connected circuit. The current generated by the power supply is then adjusted to increase or decrease the current density in the superconducting magnet to respectively ramp up or ramp down the magnetic field strength in a controlled manner. The ramp rate at which the magnetic field strength is changed is determined and optimized based on the operating parameters of the superconducting magnet and the current being generated by the power supply.

Abstract: Methods for analyzing a formation samples using nuclear magnetic resonance (NMR) are described herein. One method includes performing an NMR measurement of the formation sample to obtain NMR data. The NMR measurement detects NMR signals with echo times of less than or equal to 100 microseconds. The NMR data is analyzed to determine a measure of organic hydrogen content of the formation sample, such as (i) total organic hydrogen content, (ii) kerogen content, (iii) bitumen content, and/or (iv) oil content.

Abstract: A magnetic resonance data acquisition unit is operated according to an imaging protocol wherein at least one echo spacing exists following radiation of an excitation RF pulse, via an RF channel that includes an RF amplifier, and a subsequent readout of an echo. Loading of the RF amplifier is reduced by lengthening the echo spacing in the imaging protocol. One or more refocusing RF pulses are radiated with a lengthened echo spacing.

Abstract: In a method to determine a control sequence for a magnetic resonance imaging system in order to acquire echo signal-based raw magnetic resonance data in k-space along one or more trajectories on the basis of the control sequence, the control sequence is optimized so that, to control a gradient magnetic field for at least a predetermined portion of the control sequence, a change of an attribute of the gradient magnetic field is limited. The limitation takes place so that a momentary amplitude change rate of the gradient magnetic field falls below a predetermined amplitude change rate limit value, and/or so that a momentary direction change rate of the gradient magnetic field falls below a predetermined direction change rate limit value, and/or so that a momentary gradient change rate of the gradient magnetic field that is based on a combination of the momentary amplitude change rate and the momentary direction change rate falls below a predetermined gradient change rate limit value.

Abstract: A data detection device is used in combination with a magnetic resonance imaging (MRI) apparatus. A magnetic field detection unit (34) serves to detect a temporally varying magnetic field generated by the MRI apparatus, and a timestamping unit (35) generates magnetic field detection timestamps in dependence of the detected temporally varying magnetic field. This allows determining a temporal relation to acquired MRI data.

Abstract: A test method for a reordering algorithm of a 3D spin echo magnetic resonance pulse sequence is provided, in which echo train positions are checked for at least two k-space elements. Further, a non-transitory computer readable medium and a magnetic resonance tomography system which comprises a test device for testing a reordering algorithm of a 3D spin echo magnetic resonance pulse sequence featuring a checking module for checking the echo train position for at least two k-space elements are provided.

Abstract: Systems and methods for efficiently generating MR images are provided. The method comprises acquiring k-space MR data, reconstructing an MR image from the k-space MR data, and generating the MR image. The MR image is reconstructed using an alternative-direction-method-of-multiplier (ADMM) strategy that decomposes an optimization problem into subproblems, and at least one of the subproblems is further decomposed into small problems. The further decomposition is based on Woodbury matrix identity and uses a diagonal preconditioner based on non-Toeplitz models.

Abstract: In a method and magnetic resonance (MR) apparatus to determine sample points of a random undersampling scheme of k-space to acquire reduced MR data with multiple coils, a set of sample points of the random undersampling scheme to acquire the reduced MR data is determined, and an indicator of a signal noise in reconstructed MR data is calculated. Furthermore, an additional sample point, which is not included in the set of sample points is determined, and a change of the indicator that results by an addition of the additional sample point to the set of sample points is calculated. The additional sample point is selectively added to the set of sample points dependent on the calculated change.

Abstract: The invention provides methods and apparatus for image processing that perform image segmentation on data sets in two- and/or three-dimensions so as to resolve structures that have the same or similar grey values (and that would otherwise render with the same or similar intensity values) and that, thereby, facilitate visualization and processing of those data sets.

Abstract: In a method to determine a B1 phase map for at least two excitation modes of a radio-frequency coil arrangement of a magnetic resonance apparatus, the radio-frequency coil arrangement having multiple independently controllable transmission channels, and the B1 phase map describing, with spatial resolution, the phase of radio-frequency field this is generated in a respective excitation mode relative to a common reference phase map, first magnetic resonance data describing the phase change of a basic magnetic field of the magnetic resonance apparatus between a first echo time and a second echo time are acquired, and are evaluated to determine a spatially resolved Larmor frequency value that describes the deviation from a nominal Larmor frequency of the magnetic resonance apparatus.

Abstract: There is provided an optically pumped magnetometer, in which a pump light having a first wavelength to spin-polarize a first alkali-metal atom group is made to enter a cell containing the first alkali-metal atom group and a second alkali-metal atom group interacting via spin exchange with the first alkali-metal atom group, a probe light having a second wavelength different from the first wavelength to measure spin polarization of the second alkali-metal atom group is made to enter the cell to form the same optical axis as the pump light, a wavelength discrimination unit is provided to discriminate between the pump light and the probe light that passed through the cell depending on a different in wavelength, and the rotation angle of a polarization plane of the probe light that passed through the cell is measured so that the degree of flexibility of the device layout can be increased.

Abstract: An imaging system and methods including a gantry defining a bore and an imaging axis extending through the bore, and at least one support member that supports the gantry such that the imaging axis has a generally vertical orientation, where the gantry is displaceable with respect to the at least one support member in a generally vertical direction. The imaging system may be configured to obtain a vertical imaging scan (e.g., a helical x-ray CT scan), of a patient in a weight-bearing position. The gantry may be rotatable between a first position, in which the gantry is supported such that the imaging axis has a generally vertical orientation, and a second position, such that the imaging axis has a generally horizontal orientation. The gantry may be displaceable in a horizontal direction and the system may perform a horizontal scan of a patient or object positioned within the bore.

Abstract: A methods are provided for investigating a sample containing hydrocarbons by subjecting the sample to a nuclear magnetic resonance (NMR) sequence using NMR equipment, using the NMR equipment to detect signals from the sample in response to the NMR sequence, analyzing the signals to extract a distribution of relaxation times (or diffusions), and computing a value for a parameter of the sample as a function of at least one of the relaxation times (or diffusions), wherein the computing utilizes a correction factor that modifies the value for the parameter as a function of relaxation time for at least short relaxation times (or as a function of diffusion for at least large diffusion coefficients).

Abstract: An apparatus is disclosed as having, for example, a frame, a support assembly, and a pivot joint pivotably connected to the frame and the support assembly for positioning in a plurality of modes including, for example, a user in supine, standing, and/or prone positions. The apparatus may be positioned within various ranges that include supine and prone modes without re-configuring the apparatus.

Abstract: A method of measuring NMR response in an NMR instrument includes heating a sample at a heater temperature that is higher than the temperature of the interior of the NMR instrument, positioning the heated sample in the NMR instrument, and measuring the NMR response of the heat sample. Typically, the sample is dry and includes fat. Furthermore, a method of determining an amount of a component of a sample includes positioning a sample in an NMR instrument, applying a sequence of radio-frequency pulses to the sample, measuring the amplitudes of the signals produced by the application of the sequence of radio-frequency pulses, and determining the amount of a component in the sample using the measured amplitudes of the signals. The disclosed methods typically provide accurate analysis of samples in a shorter time period than traditional NMR techniques and solvent-based analysis techniques.

Abstract: According to one embodiment, an MRI apparatus includes a data acquisition unit and an image generation unit. The data acquisition unit acquires an analog MR signal from an object and converts the analog MR signal into a digital MR signal. The image generation unit generates MR image data based on the digital MR signal. The data acquisition unit includes an AD converter, a signal processing part and a noise suppression part. The AD converter converts the analog MR signal, before a down conversion, into the digital MR signal, inside an imaging room. The signal processing part performs signal processing of the digital MR signal, inside the imaging room or outside the imaging room. The noise suppression part suppresses a noise arising caused by a conversion from the analog MR signal, before the down conversion, into the digital MR signal.