Abstract: Noise information describing general noise properties of a magnetic resonance imaging apparatus (MRIA) in an imaging volume is measured using a predetermined first magnetic resonance sequence. Patient image data is acquired in at least one imaging region of a patient using a predetermined second magnetic resonance sequence. An anatomical landmark of a group of predetermined anatomical landmarks is localized in the patient image data by a landmark detection algorithm. For landmarks, reference information regarding imaging quality information is provided in a database. A landmark-specific signal-to-noise ratio is determined for each localized landmark from the patient image data at the landmark and the noise information, and the imaging quality information is determined from the landmark-specific signal-to-noise ratio.

Abstract: In a method, by a magnetic resonance device, a transmit B1 field map is determined for a region, a plurality of MR images of at least one part of the region are acquired using transmitter settings differing from each other, and signal intensities of individual pixels measured by the MR images are interpolated by the transmit B1 field map. A correction of the signal intensities may also be effected by carrying out a receive B1 correction by a spatial mirroring of the transmit B1 field map on a symmetry plane of a measured object. A magnetic resonance device is used to carry out the method. The method may be applied, for example, in medical diagnostics.

Abstract: In a method and apparatus for correcting image data acquired by an image data acquisition scanner of a magnetic resonance system, a reception profile of a reception antenna of the magnetic resonance scanner is determined. A correction function is determined by which an asymmetry of the reception profile with respect to a symmetry plane is corrected. Furthermore, image data are received and corrected by multiplying the intensity values of the image data with the determined correction function.

Abstract: In a method for the determination of sensitivity profiles of local coils in the acquisition of magnetic resonance data, a first measurement data set of an examination area is acquired with a first acquisition coil, a second measurement data set of the examination area is acquired with a local coil, and a sensitivity profile of the local coil that is used is determined on the basis of the first measurement data set and the measurement data set. The first measurement data set and the second measurement data set are acquired using a pulse sequence with ultrashort echo times. In the determination of the sensitivity profile, errors due to dephasings are avoided as best as possible by the acquisition of the measurement data sets with a pulse sequence with ultrashort echo times (i.e. in particular echo times TE shorter than 0.5 ms); in particular, the dephasings are smaller given these echo times than in the case of gradient echo (GRE)-based pulse sequences.

Abstract: In a method and apparatus for correcting image data acquired by an image data acquisition scanner of a magnetic resonance system, a reception profile of a reception antenna of the magnetic resonance scanner is determined. A correction function is determined by which an asymmetry of the reception profile with respect to a symmetry plane is corrected. Furthermore, image data are received and corrected by multiplying the intensity values of the image data with the determined correction function.

Abstract: In a method and apparatus to reduce movement artifacts in magnetic resonance images an essentially unmoving area of a region to be imaged is located in a region of high sensitivity of a first group of individual local antennas, and a moving area is located in the region of high sensitivity of a second group of local antennas. Spatially coded magnetic resonance signals are received by a first group of the local antennas and are individually processed further. Spatially coded nuclear magnetic resonance signals are received by the second group of local antennas and are combined with a weighting, using weighting factors. The weighting factors are determined so as to reduce gradient of the weighted, combined, spatially dependent sensitivity of the local antennas of the second group.

Abstract: In a method, by a magnetic resonance device, a transmit B1 field map is determined for a region, a plurality of MR images of at least one part of the region are acquired using transmitter settings differing from each other, and signal intensities of individual pixels measured by the MR images are interpolated by the transmit B1 field map. A correction of the signal intensities may also be effected by carrying out a receive B1 correction by a spatial mirroring of the transmit B1 field map on a symmetry plane of a measured object. A magnetic resonance device is used to carry out the method. The method may be applied, for example, in medical diagnostics.

Abstract: A method for time synchronization of various components of a magnetic resonance system includes generating a series of amplitude-modulated radio-frequency pulses and associated gradient fields to deflect the magnetization of a slice detecting at least two spin signals, determining a phase difference between two of the spin signals, processing the phase difference in order to determine at least one time shift between two of the following variables that are generated by different components of the magnetic resonance system, an envelope of the amplitude-modulated radio-frequency pulses, a radio-frequency portion of the amplitude-modulated radio-frequency pulses, and one or more gradient fields, and synchronizing the associated components of the magnetic resonance system depending on the at least one time shift.

Abstract: In a method and apparatus to generate a magnetic resonance (MR) image in a volume of interest of an examination subject, the magnetization is excited in an additional volume in the subject by at least one RF pulse, in order to achieve a desired magnetization in the volume of interest. The additional excitation volume differs at least partially from the volume of interest. For this purpose, at least one MR overview image of the examination subject is analyzed automatically to determine a position of at least one anatomical structure of the examination subject, from which the volume of interest is automatically determined. The additional excitation volume is automatically determined using the position of the at least one anatomical structure. The MR image in the volume of interest is acquired with excitation of the magnetization in the automatically determined additional excitation volume.

Abstract: In a method for the determination of sensitivity profiles of local coils in the acquisition of magnetic resonance data, a first measurement data set of an examination area is acquired with a first acquisition coil, a second measurement data set of the examination area is acquired with a local coil, and a sensitivity profile of the local coil that is used is determined on the basis of the first measurement data set and the measurement data set. The first measurement data set and the second measurement data set are acquired using a pulse sequence with ultrashort echo times. In the determination of the sensitivity profile, errors due to dephasings are avoided as best as possible by the acquisition of the measurement data sets with a pulse sequence with ultrashort echo times (i.e. in particular echo times TE shorter than 0.5 ms); in particular, the dephasings are smaller given these echo times than in the case of gradient echo (GRE)-based pulse sequences.

Abstract: In a method and apparatus to reduce movement artifacts in magnetic resonance images an essentially unmoving area of a region to be imaged is located in a region of high sensitivity of a first group of individual local antennas, and a moving area is located in the region of high sensitivity of a second group of local antennas. Spatially coded magnetic resonance signals are received by a first group of the local antennas and are individually processed further. Spatially coded nuclear magnetic resonance signals are received by the second group of local antennas and are combined with a weighting, using weighting factors. The weighting factors are determined so as to reduce gradient of the weighted, combined, spatially dependent sensitivity of the local antennas of the second group.

Abstract: In a method and apparatus to generate a magnetic resonance (MR) image in a volume of interest of an examination subject, the magnetization is excited in an additional volume in the subject by at least one RF pulse, in order to achieve a desired magnetization in the volume of interest. The additional excitation volume differs at least partially from the volume of interest. For this purpose, at least one MR overview image of the examination subject is analyzed automatically to determine a position of at least one anatomical structure of the examination subject, from which the volume of interest is automatically determined. The additional excitation volume is automatically determined using the position of the at least one anatomical structure. The MR image in the volume of interest is acquired with excitation of the magnetization in the automatically determined additional excitation volume.

Abstract: In a method and magnetic resonance tomography apparatus for triggered implementation of a measurement (composed of partial measurements) in the magnetic resonance tomography apparatus, at least one image data set is determined from the data acquired within the scope of the partial measurements, and for triggering a reference point of the movement phase of the movement is used. The image data set is acquired in segments; the reference point is detected by a control device independent of a partial measurement, and the partial measurement following the detected reference point is conducted depending on the independently detected reference point. The wait time that specifies the interval from the end of the partial measurement to the beginning of the next partial measurement is adapted depending on the point in time of detection.

Abstract: A method for time synchronization of various components of a magnetic resonance system includes generating a series of amplitude-modulated radio-frequency pulses and associated gradient fields to deflect the magnetization of a slice detecting at least two spin signals, determining a phase difference between two of the spin signals, processing the phase difference in order to determine at least one time shift between two of the following variables that are generated by different components of the magnetic resonance system, an envelope of the amplitude-modulated radio-frequency pulses, a radio-frequency portion of the amplitude-modulated radio-frequency pulses, and one or more gradient fields, and synchronizing the associated components of the magnetic resonance system depending on the at least one time shift.

Abstract: In a method and apparatus for magnetic resonance imaging on the basis of a gradient echo sequence by excitation of nuclear spins and measurement of radio-frequency signals indicating the excited nuclear spins, a) the pulse frequency of the person to be examined is determined, b) the magnetization of the spins is prepared by means of an RF pulse block, c) a number of steps of the spin excitation as well as measurement of an RF response signal are implemented, with the measurement data along a trajectory established by projection gradients being acquired along a first slice established by a slice-selection gradient, d) items b) through c) are repeated multiple times for the first slice, with each repetition of the steps b) through c) ensuing within a time interval that is fixed in duration, and the interval is temporally displaced relative to the determined pulse frequency for at least one portion of the repetitions, and e) items b) through d) are repeated for various slices.

Abstract: In a method and magnetic resonance tomography apparatus for triggered implementation of a measurement (composed of partial measurements) in the magnetic resonance tomography apparatus, at least one image data set is determined from the data acquired within the scope of the partial measurements, and for triggering a reference point of the movement phase of the movement is used. The image data set is acquired in segments; the reference point is detected by a control device independent of a partial measurement, and the partial measurement following the detected reference point is conducted depending on the independently detected reference point. The wait time that specifies the interval from the end of the partial measurement to the beginning of the next partial measurement is adapted depending on the point in time of detection.