Abstract: In a magnetic resonance a method and apparatus to generate images by a parallel acquisition technique, a first echo train is generated after a first excitation pulse, wherein the first echo train sufficiently densely scans a segment of k-space to be scanned for an acquisition of coil calibration data. Coil calibration data are acquired by means of the first echo train after the first excitation pulse. The acquired coil calibration data are stored in a coil calibration data set. A second echo train is generated after a second excitation pulse, wherein the second echo train undersamples a segment of k-space to be scanned for an acquisition of image data. Image data are acquired by means of the second echo train after the second excitation pulse. The acquired image data are stored in an incomplete image data set. An image data set is generated by substituting data missing in the incomplete image data set due to the undersampling by means of a selected PAT reconstruction technique using the coil calibration data.

Abstract: In a method and magnetic resonance apparatus to display progress of the acquisition of measurement data of an examination region of an examination subject during continuous travel of the examination region through a magnetic resonance apparatus, a current projection image is calculated on the basis of current measurement data acquired from central k-space during the continuous travel of the examination region, and the currently calculated projection image is displayed. By the calculation of the projection images on the basis of measurement data from central k-space, this calculation can ensue particularly quickly and with little effort. A particularly fast display of the projection images is therefore possible. A projection image can be calculated particularly quickly and simply from measurement data along a central k-space line—i.e. a k-space line that runs through the center of k-space—using a one-dimensional Fourier transformation along this central k-space line.

Abstract: In a method and a device to control a workflow of an MR measurement in a magnetic resonance system, MR signals from multiple slices of a predetermined volume segment of an examination subject are acquired, multiple slices with a continuous table feed. In the MR measurement, one of these multiple slices in the active volume of the magnetic resonance system is repeatedly measured in succession at different measurement positions Pi in an order corresponding to the index of the measurement positions Pi. The measurement positions Pi are determined via the following Equation, starting from a largely arbitrary first measurement position P1 selected in the active volume of the magnetic resonance system: P i = P i - 1 + d × ( ± c - 1 + c c + e × ( 1 - TR - TB TR ) ) , ? ? ? for ? ? i = 2 , … ? , c + e , wherein d is a slice interval, c is a natural number greater than 1 and e is a whole number that is not greater than c and not less than 0.

Abstract: In a method to generate an MR angiography image of an examination region of a subject without the use of contrast agent, a first MR image of the examination region is acquired with a first imaging sequence in which a gradient-induced phase development for unmoved and moved spins is essentially completely rephased at the end of a repetition interval TR, and a second MR image of the examination region is acquired with a second imaging sequence in which the gradient-induced phase development for unmoved spins is likewise essentially completely rephased at the end of the repetition interval TR and a rest phase ?rest for moved spins remains at the end of the repetition interval TR. The second MR image is subtracted from the first MR image to generate the MR angiography image.

Abstract: In a method and apparatus for the acquisition of measurement data of an examination region of an examination subject (in particular a patient) during continuous travel of the examination region through a magnetic resonance apparatus for the generation of an image data set, the continuous travel is interrupted and resumed at least once. The examination region is moved back by a predeterminable distance counter to the travel direction of the continuous travel before interrupting the continuous travel. Moving the examination region back makes it possible to interrupt and resume an acquisition of measurement data given (otherwise) continuous travel of the examination region, without loss of measurement data. The time during the interruption can be used advantageously for preparation of an acquisition of measurement data in the portion of the examination region of the patient that is to be examined after the interruption of the continuous travel.

Abstract: In a magnetic resonance method and apparatus, a) data points of a physiological signal are detected, b) a trigger condition is evaluated depending on the detected physiological data points, c) a preparation module is executed to suppress unwanted signals in the time period in which the trigger condition has not yet been satisfied, d) after satisfying the trigger condition, an acquisition phase of predetermined duration is started, that includes at least two similar preparation modules to suppress unwanted signals and a respective following acquisition module to acquire measurement data, and e) after the acquisition phase, a) through d) are repeated until all desired measurement data have been acquired, with a time interval between two successive preparation modules being the same after a first execution of a preparation module in c) until the end of the acquisition phase in a subsequent d).

Abstract: In a method and magnetic resonance (MR) for reduction and correction of image distortions that occur in the generation of MR images of an examination subject that is arranged on a table that is continuously driven through the MR system during the generation of the MR images and whose cause is the acquisition of MR data of an image at varying positions within the MR system, raw MR data are acquired in multiple segments with radial filling of k-space with the raw data, an intersection region in the k-space center is determined that is covered by multiple segments given the radial filling of the raw data in k-space, and the distortions are automatically calculated based on the intersection region of at least two different segments.

Abstract: In a method to determine the actual flip angle in magnetic resonance tomography with continuous table feed, at least one echo signal is generated by a pulse sequence from which an actual flip angle is produced with at least one RF pulse of the sequence, and a gradient scheme is used in the direction of the continuous travel of the examination subject, the gradient scheme being designed such that its first moment disappears at the points in time of each echo signals used for the determination of the flip angle. Such a pulse sequence is also used in a method for adjustment of the transmitter voltage for RF pulses given continuous travel of the examination subject in a magnetic resonance apparatus.

Abstract: In a method and system to adjust at least one shim current in a shim channel of a magnetic resonance apparatus and an associated RF center frequency for the radio-frequency system of the magnetic resonance apparatus during an interleaved multislice MR measurement of a moving examination subject, in which MR measurement at least two excitations are implemented for complete acquisition of the desired data of a slice of the examination subject that is to be measured, the multislice MR measurement is implemented such that phase discontinuities between measurement data acquired after individual excitations are avoided.

Abstract: A method and magnetic resonance tomography system to generate magnetic resonance image data of an examination subject, raw imaging data are acquired from multiple slices of a predetermined volume region of the examination subject using local coils during a table feed in the magnetic resonance scanner. Image data of the slices are reconstructed on the basis of the raw imaging data. A normalization of the image data is subsequently implemented on the basis of measured coil sensitivity data of the local coils that are used.

Abstract: In a method and magnetic resonance (MR) for correction of movement in the acquisition of MR images of an examination region, wherein the movement that occurs between the acquisition of data of spatially different slices of the examination region is taken into account, data from the examination region are acquired in multiple slices that are acquired in at least two groups, with slices of a second group arranged at least partially between slices of the first group, such that at least one slice of the second group lies between slices of the first group. Correction for movement of the examination region that occurred between the acquisition of data of the slices of the first group and the acquisition of data of an intervening slice of the second group is done by reconstructing a reference data set for the intervening slice from acquired slice data of the first group for the movement correction.

Abstract: The invention concerns a method and magnetic resonance apparatus for acquisition and generation of a time-resolved image series of an anatomical organ with a quasi-periodical movement in a subject, k-space is sampled in segments with a number of partial data sets, with the sampling points of each partial data set corresponding to grid points of a Cartesian sampling grid of a k-space segment, and the Cartesian sampling grids of the k-space segments being rotated relative to one another. A series of sub-data sets is incompletely acquired for each partial data set using alternating sampling schemes. Each incomplete sub-data set is associated with one of the individual images. For at least some of the partial data sets, complete sub-data sets are reconstructed from the incomplete sub-data sets. For the reconstruction of the individual images, in each of the individual images, at least some of the complete sub-data sets that are associated with this individual image are used.

Abstract: In a method for the detection of signal data corresponding to a breathing movement of an examination subject by means of magnetic resonance (MR) first and second data sets are loaded, that each include complex k-space data acquired with a navigator sequence from a common excitation volume of the examination subject. The first and second data sets are processed to identify breathing movement at the acquisition time of at least one of the data sets, by comprising a transformation of the data sets in Cartesian space and calculating a phase difference between respective complex data pointes of the data sets having the same spatial position. The processing result is stored together with a time value that depends on a point in time of the acquisition of the first data set and/or the second data set.

Abstract: A method for the acquisition of measurement data of a breathing examination subject by magnetic resonance includes the following steps: (a) detect the physiological breathing signal of the examination subject with a breathing signal detection unit, (b) evaluate the detected breathing signal in an evaluation unit, (c) based on the evaluated breathing signal, calculate in a computer at least one parameter affecting the type of acquisition of measurement data by means of magnetic resonance, (d) detect a current physiological breathing signal with the breathing signal detection unit, (e) compare the last detected breathing signals with at least one trigger condition, (f) initiate the acquisition of measurement data using the calculated parameter from step (c) upon satisfaction of the trigger conditions from step (e), (g) repeat the steps (d) through (f) until all desired measurement data have been acquired, and (h) store and/or process the acquired measurement data in a memory and/or processing unit.

Abstract: In a method to generate an MR angiography image of an examination region of a subject without the use of contrast agent, a first MR image of the examination region is acquired with a first imaging sequence in which a gradient-induced phase development for unmoved and moved spins is essentially completely rephased at the end of a repetition interval TR, and a second MR image of the examination region is acquired with a second imaging sequence in which the gradient-induced phase development for unmoved spins is likewise essentially completely rephased at the end of the repetition interval TR and a rest phase ?rest for moved spins remains at the end of the repetition interval TR. The second MR image is subtracted from the first MR image to generate the MR angiography image.

Abstract: In a magnetic resonance (MR) image reconstruction method and MR apparatus, for raw MR data are acquired with the propeller technique, and k-space sampling ensues in sub-data sets. The sample points of each sub-data set correspond to grid points of a Cartesian initial grid and the Cartesian initial grid of the sub-data sets can be brought into congruence by rotation: A Cartesian final grid is selected, and a calculation-based transfer of the data points of each sub-data set ensues to a respective new grid that exhibits the orientation of the respective sub-data set and the grid constants of the final grid, if the grid constants of the output grid differ from those of the final grid. A calculation-based transfer of the data points of each sub-data set, or the data points of a respective new grid (if obtained) ensures to the final grid by the application of a rotation module followed by transformation of the acquired data into the image domain.

Abstract: In a method and a device to control a workflow of an MR measurement in a magnetic resonance system, MR signals from multiple slices of a predetermined volume segment of an examination subject are acquired, multiple slices with a continuous table feed. In the MR measurement, one of these multiple slices in the active volume of the magnetic resonance system is repeatedly measured in succession at different measurement positions Pi in an order corresponding to the index of the measurement positions Pi. The measurement positions Pi are determined via the following Equation, starting from a largely arbitrary first measurement position P1 selected in the active volume of the magnetic resonance system: P i = P i - 1 + d × ( ± c - 1 + c c + e × ( 1 - TR - TB TR ) ) , ? ? ? for ? ? i = 2 , … ? , c + e , wherein d is a slice interval, c is a natural number greater than 1 and e is a whole number that is not greater than c and not less than 0.

Abstract: In a method and apparatus for the acquisition of measurement data of an examination region of an examination subject (in particular a patient) during continuous travel of the examination region through a magnetic resonance apparatus for the generation of an image data set, the continuous travel is interrupted and resumed at least once. The examination region is moved back by a predeterminable distance counter to the travel direction of the continuous travel before interrupting the continuous travel. Moving the examination region back makes it possible to interrupt and resume an acquisition of measurement data given (otherwise) continuous travel of the examination region, without loss of measurement data. The time during the interruption can be used advantageously for preparation of an acquisition of measurement data in the portion of the examination region of the patient that is to be examined after the interruption of the continuous travel.

Abstract: In a method and magnetic resonance apparatus to display progress of the acquisition of measurement data of an examination region of an examination subject during continuous travel of the examination region through a magnetic resonance apparatus, a current projection image is calculated on the basis of current measurement data acquired from central k-space during the continuous travel of the examination region, and the currently calculated projection image is displayed. By the calculation of the projection images on the basis of measurement data from central k-space, this calculation can ensue particularly quickly and with little effort. A particularly fast display of the projection images is therefore possible. A projection image can be calculated particularly quickly and simply from measurement data along a central k-space line—i.e. a k-space line that runs through the center of k-space—using a one-dimensional Fourier transformation along this central k-space line.

Abstract: In a magnetic resonance method and apparatus to generate images by a parallel acquisition technique an excitation pulse is radiated into an examination subject, and a first echo train is generated after the excitation pulse, wherein the first echo train densely scans a segment of k-space to be scanned for an acquisition of coil calibration data. Coil calibration data are acquired by means of the first echo train. The acquired coil calibration data are stored in a coil calibration data set. A second echo train is generated after the same excitation pulse, wherein the second echo train undersamples a segment of k-space to be scanned for an acquisition of image data. Image data are acquired by means of the second echo train. The acquired image data are stored in an incomplete image data set. An image data set is generated by substituting data missing in the incomplete image data set due to the undersampling by means of a selected PAT reconstruction technique using the coil calibration data.