Abstract: Acquisition of MR data with a compressed sensing technique in a volume section includes ascertaining an extent of magnetic field distortion within the volume section. A first gradient along a first direction is switched. An RF excitation pulse is radiated for selective excitation of a slice in the volume section while the first gradient is switched. The MR data is acquired in a volume of the volume section that is composed of the slice, a partial volume above the slice, and a partial volume below the slice by executing the following multiple times: switching a first phase-encoding gradient along a second direction; switching a second phase-encoding gradient along the first direction; and reading out the MR data in a k-space line while a readout gradient is switched along a readout direction. A set of k-space lines to be read out for the volume is determined in dependence on the extent.

Abstract: A correction method for reducing temperature-related deviations in a gradient response of an MR pulse sequence in MR imaging is provided. An MR pulse sequence that includes at least one nominal test gradient is run. A gradient response to the at least one nominal test gradient is repeatedly acquired by a magnetic field measurement in an examination region. A gradient system transfer function is determined based on the gradient response. A corrected MR pulse sequence is determined based on the gradient system transfer function and of the at least one nominal test gradient.

Abstract: In a method for recording measurement data, frequency-dependent parameters characterizing a gradient unit are loaded, a k-space trajectory planned for a MR measurement and having at least one frequency component is loaded, MR measurement data is acquired based on the planned k-space trajectory and reconstructing image data from the MR measurement data, wherein the planned k-space trajectory is corrected based on the at least one frequency component of the planned k-space trajectory and the frequency-dependent parameters, and an electronic signal representing the reconstructed image data is provided as an output of the MR system. The reconstructed image data may be stored and/or displayed. Advantageously, the correction can be employed flexibly for k-space trajectories with different frequency components.

Abstract: Techniques are disclosed relating to the generation of a magnetic resonance (MR) image of a predetermined portion of a volume of an examination object. MR data of the portion may be acquired using echo trains in a first step and in a second step, with each of the echo trains acquiring MR data of a plurality of k-space lines. The plurality of k-space lines extend parallel to one another and perpendicular to a common plane such that per k-space line, one intersection point within a plane results. The MR image is then reconstructed using the acquired MR data.

Abstract: In a method for detecting MR signals of an object in an MR scanner, in which the MR signals of the object are detected with receiving channels at the same time using a parallel imaging technique, where the MR signals are spin-echoes generated with a spin-echo based imaging sequence, a first magnetic field gradient (MFG) is applied in a slice selection direction (SSD) while applying an RF excitation pulse of the spin echo based imaging sequence, the first MFG having a first polarity during the application of the RF excitation pulse, a second MFG is applied in the SSD while applying at least a first RF refocusing pulse of the spin echo based imaging sequence, the second magnetic field gradient has a second polarity opposite to the first polarity, and the MR signals of the spin echo are detected to generate an MR image based on the detected MR signals.

Abstract: The invention relates to a plug-in module for a sensor (32) comprising a sleeve-like housing (3) in which a sensor element (27), a carrier board (16) carrying an electronic circuit and a plug-in unit (2) are positioned. In a plug-in module which can be used equally for sensors of different sizes, an outer diameter (5) of the plug-in unit (2) approximately corresponds to a smallest inner diameter (8) of the sleeve-like housing (3), wherein a coding sleeve (4) is inserted between the plug-in unit (2) and the sleeve-like housing (3).

Abstract: A method serves for MR-based reconstruction of images of a patient. Whether a value of a movement of the patient in at least one motion direction during an MR scan exceeds a respective threshold value is monitored. If this is not the case, an image reconstruction is performed by a Wave-CAIPI method on the basis of identical calibrated PSF subfunctions for all k-space lines. When this is the case, a number of bins are provided that correspond to sequential value ranges of the patient movement in at least one motion direction, the k-space lines are assigned to the bins based on a movement value determined during their respective acquisition, a calibration of PSF subfunctions is performed for at least two bins on the basis of the k-space lines assigned to said bins, and an image reconstruction is performed by a Wave-CAIPI method in such a way that the PSF subfunctions associated with the assigned bins are used for the respective k-space lines.

Abstract: A computer-implemented method is provided for generating correction information for correcting mismatches in magnetic resonance measurements. Magnetic resonance data is received, wherein a generation of the magnetic resonance data includes several partial measurements by a magnetic resonance device. During each partial measurement, a k-space region is sampled at least partially, wherein the k-space regions of different partial measurements differ at least partially in their extent in the readout direction, and wherein the extent in the readout direction depends on prephasing gradients and readout gradients generated by the magnetic resonance device during the partial measurements. A trained function of a machine learning algorithm is applied to the received magnetic resonance data, wherein correction information for correcting a mismatch of the prephasing gradients and readout gradients is generated and output.

Abstract: For improving image quality in MRI, a method for magnetic of an object is provided that includes obtaining MRI data during at least a first and a second acquisition step. Each acquisition step includes at least two data acquisition periods. A movement of the object is monitored by a camera system during the acquisition steps. Data obtained during the acquisition periods is adjusted based on the monitoring. Data obtained during a first reference period of the first acquisition step is compared to data obtained during a second reference period of the second acquisition step. The obtained or adjusted data is corrected based on a result of the comparison.

Abstract: A storage medium, a magnetic resonance apparatus, and a method for obtaining a correction factor to balance a mismatch between gradient moments are disclosed herein. The method includes providing a magnetic resonance raw dataset, the generation of which includes acquiring the k-space of the magnetic resonance raw dataset in several partial measurements, wherein in each partial measurement, several k-space lines are at least partially sampled by setting a given set of acquisition parameters, applying at least one radio frequency excitation pulse, applying a first gradient in a predetermined direction, applying a second gradient in the predetermined direction, and reading out the magnetic resonance signals.

Abstract: A method is provided for generating a signal-to-noise improved magnetic resonance (MR) image of an object under examination in an MR system using a compressed sensing technology. The method includes determining a first MR signal data set of the object under examination in which a corresponding k-space is randomly subsampled; determining a location dependent sensitivity map for each of at least one receiving coil used to detect MR signals of the first MR signal data set in the location where the object under examination is located; and determining the MR image using an optimization process of the compressed sensing technology in which a location dependent regularization parameter is used, wherein the location dependent regularization parameter is determined based on the location dependent sensitivity map.

Abstract: In a method and apparatus for generating a magnetic resonance data record, at least two excitation cycles are executed, wherein, in each excitation cycle, at least one magnetic resonance signal is recorded, using different phases with a first radio-frequency pulse in two consecutive excitation cycles, with at least one dephasing gradient being applied in an excitation cycle.

Abstract: In a method and apparatus for characterizing an obstacle within an examination object using a medical image data set by the use of a database containing at least one data class, a trained artificial neural network defines and develops relationships between different obstacles, features and medical imaging data sets. A data entry of a data class is assigned by the neural network to the obstacle within the examination object and the obstacle within the examination object is characterized in an electronic output by this data entry.

Abstract: In a method for MRI of an object, spins of a first material and spins of a second material are excited. An in-phase echo signal is acquired when the spins are in-phase and an out-of-phase echo signal is acquired, when the spins are out of phase. A first image for the first material and/or a second image for the second material is generated by a computing unit depending on the in-phase echo signal and the out-of-phase echo signal. For acquiring the out-of-phase echo signal, a momentum space is sampled asymmetrically in a read-out direction.

Abstract: In a method for generating at least one MR image of an object in an MR system comprising a plurality of signal receiving coils, a sequence of RF pulses are applied in order to generate a plurality of MR signal echoes, the MR signal-echoes are detected with the plurality of signal receiving coils in a 3-dimension-al k-space, and the at least one MR image is reconstructed using the non-homogeneous under sampled 3-dimensional k-space based on a compressed sensing technology. The 3-dimensional k-space may be undersampled with a plurality of spiral trajectories having different radii resulting in a non-homogeneous undersampled 3-dimensional k-space.

Abstract: In a method for operating an MRI device, image data is acquired using a spin echo sequence with an additional readout per pulse train for acquiring correction data. By comparing subsequent correction data of later pulse trains to reference data acquired during a first pulse train of the sequence a difference indicating a parameter shift is determined. A corresponding compensation is then automatically determined in dependence on the difference and is applied to a set of predetermined parameters for at least a respective next pulse train and/or to the image data acquired in at least a respective next pulse train of the sequence.

Abstract: In a method for generating an MR image of an object, k-space of the MR image is separated into blades. In each blade, parallel k-space lines are provided which are separated in a phase encoding direction (PED). Each blade has a different rotation angle around a common center relative to the remaining blades. A spatial extent of the object is determined. For the blades, the extent of the object in the corresponding PED is determined. A blade specific extent of a field of view (FOV) in the PED is determined for each of the blades based on the corresponding extent of the object in the PED. The extent of the FOV in the PED differs for at least one of the blades from the extent of the remaining blades, and sampling the k-space with the blades with the determined blade specific FOV as determined for each of the blades.

Abstract: Techniques are disclosed related to recording a magnetic resonance image data set of a region of a patient with a magnetic resonance device using a multislice imaging technique. The multislice technique may be applied simultaneously with at least partial undersampling in a slice plane. The magnetic resonance data may be read out from a set of excited slices simultaneously and, by means of a slice separation algorithm that is calibrated using reference data recorded in a separate reference scan, may be allocated to the simultaneously read-out slices. Subsequently, an undersampling algorithm compensating for the undersampling in the slice plane may be applied to the undersampled magnetic resonance data of the individual slices.

Abstract: A rapid self-orienting personal defense device is provided having an elongate body, a stream channel, an orientation guide, a contact feature, and a contoured grip. The body defines an elongate storage cavity therein for retaining a replaceable repellant storage container. The orientation guide has a tip portion defining an index finger locator surface facing downward when gripped by the user for readily identifying to the user an intended grip location and orientation based on contact between the index finger with the locator surface. The contact feature can be attached to the tip portion of the orientation guide for providing defensive contact with an attacker and collecting a DNA sample during defensive contact. The contoured grip can have a grip diameter corresponding with the user. The orientation guide, locator surface and contoured grip can provide rapid self-orientation of the device when grabbed by the user.

Abstract: In a method and magnetic resonance (MR) apparatus for reducing artifacts in an image dataset reconstructed from MR raw data that were acquired by radial sampling using different coil elements, for each of at least some of the coil elements, exclusion information is determined that identify MR data from that coil element that are responsible for at least one artifact, by a comparison of a sensitivity map, which defines a spatial reception capability of that coil element, with at least one comparison dataset obtained from at least a portion of the MR data from that coil element. At least the MR data identified from the exclusion information are excluded from the reconstruction of the image dataset.