Abstract: In a method and apparatus for recording a magnetic resonance dataset with a number of reception coils, wherein the measurement signals of the magnetic resonance dataset contain measurement signals from at least two slices, the measurement signals are recorded segmented by the measurement signals being recorded in a first area of k-space with a first scanning density and in a second area of k-space with a second scanning density.

Abstract: In a magnetic resonance (MR) apparatus and operating method, a first pulse sequence is executed in order to acquire echo signals from a target volume produced by radiation of a radio-frequency (RF) excitation pulse, thereby obtaining an original measurement dataset. A reference measurement dataset is then acquired by executing another pulse sequence immediately after acquisition of the aforementioned echo signals. These steps are repeated until the original measurement dataset has reached a predetermined degree of completeness that is still incomplete according to the Nyquist criterion. The original measurement dataset is then completed using the reference measurement dataset and a parallel acquisition technique.

Abstract: In a method for reconstructing contrast levels from magnetic resonance (MR) acquisitions using a parallel acquisition (PAT) technique, MR raw data for at least two contrast levels are generated or acquired, the raw data includes reference lines. Reference line images are reconstructed from the reference lines of the MR raw data for at least two of the contrast levels. A histogram analysis is implemented on the basis of the reference line images. A PAT reconstruction of image representations of the different contrast levels is implemented, wherein the decision as to which reference lines are used for the PAT reconstruction being made on the basis of the histogram analysis.

Abstract: In a pulse sequence that is produced and used for controlling a magnetic resonance imaging system as part of an inversion recovery measurement sequence, a number of partial volumes to be imaged are excited, wherein the pulse sequence includes a start sequence followed by an excitation sequence. The start sequence is series arrangement of a succession of at least two initial inversion pulses for inverting partial volumes. The excitation sequence is series arrangement of excitation blocks and additional inversion pulses, with each excitation block being followed by additional inversion pulses, so that excitation blocks and additional inversion pulses always alternate.

Abstract: In a method and apparatus for recording magnetic resonance (MR) data of a target region of a subject, the recording process is divided into subsections each follow the other after a repetition time. Before each recording of MR data of a subsection with a measurement sequence, an adiabatic preparatory pulse is activated that inverts the longitudinal magnetization of a saturation molecule type, from which no MR data are to be recorded. An excitation pulse is emitted spaced by an inversion time from the preparatory pulse. Before the first preparatory pulse, at least one adiabatic preparation pulse is emitted that inverts the longitudinal magnetization with a timing such that the longitudinal magnetization of the saturation molecule type at the time of the first preparatory pulse at a steady state value, which occurs again before the repetition time after each preparatory pulse.

Abstract: In a method and apparatus for recording magnetic resonance data for determining at least one parameter map describing a material parameter in the scanning region, the scanning area having a number of slices, a slice-specific preparation pulse is used, wherein magnetic resonance data are scanned after different waiting times following the preparation pulse. Magnetic resonance data of different waiting times are acquired from at least two slices, by determining an overall pulse by overlaying the slice-specific preparation pulses for the individual slices, and then activating the overall pulse to read out the magnetic resonance data of the slices with a readout sequence after the respective waiting times.

Abstract: In a method and apparatus for generating magnetic resonance (MR) measurement data of an object, (a) a multiband RF excitation pulse is radiated into the object to simultaneously selectively excite at least two slices, which do not overlap, in the object, and (b) echo signals generated are read out with at least two reception coils and are stored in a measurement data record, and (c) after reading out a last echo signal that follows from the multiband RF excitation pulse, a driven equilibrium module is radiated that includes at least one further multiband RF pulse. Steps (a) to (c) are repeated with different position encoding and/or while exciting different slices, until all desired measurement data are stored in the measurement data record. The measurement data contained in the measurement data record are separated into slice-specific measurement data records on the basis of coil sensitivity data of the reception coils used for read-out purposes.

Abstract: A magnetic resonance apparatus and method acquire magnetic resonance data with a recording technique in which the Cartesian scanning of k-space is carried out differently, by a rotation of gradient directions around the center of k-space, for different recording sections of a respective part of the magnetic resonance data, and this recording technique is combined with an accelerating imaging technique for which reference data completely describing a reference range around the center of k-space are used for each individual slice to be scanned. At the beginning of the recording, a calibration area of k-space, which includes all the reference ranges required in the course of recording, is determined and a calibration data set of k-space is recorded in a calibration measurement with complete, Cartesian scanning of the calibration area. Reference data for each recording section are determined from this calibration data set.

Abstract: In a method and magnetic resonance (MR) apparatus for creating an MR 3D image dataset, spin echo sequences are used to acquire two raw datasets that are each undersampled, wherein the excitation pulses or the refocusing pulses radiated in the data acquisitions have an opposite phase for the two raw datasets. These two raw datasets are combined into a combined 3D raw dataset that is not undersampled, and a weighting matrix is calculated for use in calculating the raw data points that were not acquired in the first raw dataset and the raw data points not acquired in the second raw dataset. A first complete raw dataset and second complete raw dataset are thereby calculated, which are then combined. The MR 3D data is then reconstructed from tis combined raw dataset.

Abstract: In a method and apparatus for acquiring magnetic resonance (MR) data, an MR data acquisition scanner is operated, while a subject is situated therein to execute a simultaneous multislice (SMS) turbo spin echo (TSE) sequence by implementing a TSE-based reference scan to acquire reference data and an imaging scan, to acquire raw MR data from the subject. The reference data and the raw MR data are entered into a memory organized as k-space. A computer accesses the memory in order to make the k-space data, composed of said reference data and said image data, available in electronic form, as at least one data file.

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 magnetic resonance tomography scanner and an operating method therefor, a scanning volume is subdivided in a slice direction into multiple scanning slices, and the scan data of each of the scanning slices are acquired by a scan sequence allocated to the respective scanning slice. Each scan sequence has at least one preparation pulse allocated to the scanning slice, which causes nuclear spin excitation throughout the whole scanning volume. At least two scan sequences are implemented that differ with regard to a coil current fed during the preparation pulse to a field correction coil of the scanner for reducing a local inhomogeneity of a basic magnetic field, or that differ with regard to at least one pulse parameter of the preparation pulse. The respective coil current and/or pulse parameter is determined depending on the position of the scanning slice allocated to the respective scan sequence in the scanning volume.

Abstract: A control device establishes a change in a main magnetic field expected for a respective time instant and based on the established expected change in the main magnetic field, correctively adjusts the main magnetic field and/or a nominal receive frequency of the RF receive coil and/or a transmit frequency for subsequent RF transmit pulses and/or takes the expected change in the main magnetic field into account in the evaluation of the received MR signals. At least for some of the RF transmit pulses, the control device acquires, via a sensor device, a portion of the respective radiofrequency wave supplied to the RF transmit coil. The controller extracts therefrom an oscillation corresponding to a respiratory motion of the patient and based on the variation with time of the extracted oscillation, establishes the change in the main magnetic field expected for the respective time instant.

Abstract: In a magnetic resonance slice multiplexing method and apparatus, measurements are repeated with additional phase amounts being applied, wherein in each repetition, the additionally applied phase amounts are changed such that at least a central k-space region is fully sampled in the course of the repeated acquisitions. A calibration dataset, which is used in reconstructing image data for the simultaneously excited slices from the acquired measurement data, is determined from the measurement data that have been fully acquired in the central k-space region. The calibration dataset is updated in further measurements.

Abstract: In a method and apparatus for creating magnetic resonance data of at least two simultaneously manipulated, non-overlapping slices of an examination object by a parallel acquisition technique, reference data are acquired such that, between acquisition of slice scan data of a slice scan data set in which the scan data of all simultaneously manipulated slices are incorporated in an overlaid manner, and its associated reference data, no slice scan data of a different slice scan data set are acquired. A high level of robustness with respect to movements of the examination object is thereby achieved.

Abstract: In a magnetic resonance slice multiplexing method and apparatus, measurements are performed repeatedly subject to the assignment of additional phases to the respective slices, the additionally assigned phases being changed with reach repetition such that at least one central k-space region is sampled completely in each of the repeated acquisitions. A calibration dataset is determined from the measurement data acquired completely in the central k-space region. The calibration dataset is used when reconstructing image data for the simultaneously excited slices from the acquired measurement data.

Abstract: In a method and magnetic resonance (MR) apparatus for creating a maximum intensity projection of a volume of an examination subject, MR data are acquired for a number of slices of the volume, and an MR image is reconstructed for each of the slices that MR data have acquired in order to create a maximum intensity projection for each of the slices. The maximum intensity projection of the respective slice is shown on a display. The slices, which have a thickness of at least 15 mm, have various slice directions, in order to display the maximum intensity projections from various directions.

Abstract: In a magnetic resonance apparatus and a method for generating MR image data of a subject with parallel imaging, a reference data set of the object is recorded, in which at least one partial section of the associated raw data space is completely filled with raw data according to the Nyquist condition, and an imaging data set is recorded for the generation of the MR image data on the basis of spin-echo-based signals, in which the associated raw data space is not completely recorded according to the Nyquist condition. A weighting matrix is calculated based on the reference data set, which is used to determine raw data points of the imaging data set not recorded during parallel imaging. The unrecorded raw data points of the imaging data set are calculated using the calculated weighting matrix.

Abstract: In a method and apparatus for acquiring magnetic resonance (MR) data from multiple slices of a subject, a spin echo sequence is executed wherein a radio frequency (RF) excitation pulse, a refocusing pulse, and a further RF pulse are radiated, together with the application of a number of gradients, in order to acquire MR data from an intersection volume of a selected slice with a further slice. The MR data are entered into at least one k-space line in a memory organized as k-space.

Abstract: In a method and apparatus for generating magnetic resonance (MR) measurement data of an object, (a) a multiband RF excitation pulse is radiated into the object to simultaneously selectively excite at least two slices, which do not overlap, in the object, and (b) echo signals generated are read out with at least two reception coils and are stored in a measurement data record, and (c) after reading out a last echo signal that follows from the multiband RF excitation pulse, a driven equilibrium module is radiated that includes at least one further multiband RF pulse. Steps (a) to (c) are repeated with different position encoding and/or while exciting different slices, until all desired measurement data are stored in the measurement data record. The measurement data contained in the measurement data record are separated into slice-specific measurement data records on the basis of coil sensitivity data of the reception coils used for read-out purposes.