Abstract: In a method and device to assist a patient in the resumption of a defined breath hold position for an image acquisition, in particular a magnetic resonance image acquisition, reference data describing the defined breath hold position are acquired in a first breath hold phase by a measurement device, measurement data describing the current breath hold position are acquired with the measurement device and are compared with the reference data in the preparation of an additional breath hold phase, and information describing the deviation of the measurement data from the reference data is emitted by an output device in a humanly-perceptible form.

Abstract: For imaging a volume segment by means of a magnetic resonance system, of the volume segment is transferred into a dynamic steady state relative to the magnetization by means of the magnetic resonance system. The following steps are repeatedly executed until the volume segment has been completely measured. The slice is excited by means of the magnetic resonance system. MR signals of the slice are read out. The slice is offset in an overlapping manner such that an overlap range is created by the slice before the offset and the slice after the offset, the overlap range being a predetermined percentile of both the slice before the offset and the slice after the offset.

Abstract: In a method for optimization of a flow coding with switching of an additional bipolar dephasing gradient pair, used in a magnetic resonance (MR) phase contrast angiography, the strength of the flow coding is selected depending on the flow velocity in the vessels that should be depicted. MR signals of an examination region are acquired with continuously running overview measurements, with an operator-selected flow coding strength. After the selected flow coding strength is adopted automatically for the next measurement of the continuously running overview measurements, and two partial measurements with different flow codings are implemented for each selected strength and a phase difference image from the two partial measurements is calculated and depicted in real time, and the selected flow coding strength is automatically adopted for the MR phase contrast angiography.

Abstract: A system and method for regression-based segmentation of the mitral valve in 2D+t cardiac magnetic resonance (CMR) slices is disclosed. The 2D+t CMR slices are acquired according to a mitral valve-specific acquisition protocol introduced herein. A set of mitral valve landmarks is detected in each 2D CMR slice and mitral valve contours are estimated in each 2D CMR slice based on the detected landmarks. A full mitral valve model is reconstructed from the mitral valve contours estimated in the 2D CMR slices using a trained regression model. Each 2D CMR slice may be a cine image acquired over a full cardiac cycle. In this case, the segmentation method reconstructs a patient-specific 4D dynamic mitral valve model from the 2D+t CMR image data.

Abstract: In a method and a magnetic resonance system to automatically determine parameters of a phase contrast flow measurement, a phase contrast pre-measurement with a flow coding sequence is implemented in a predetermined volume segment of an examination subject, and the flow coding sequence is varied in terms of its parameters so that a pre-measurement is respectively implemented for multiple different parameter sets of the flow coding sequence. A model is automatically determined with which a dimension of a phase error can be determined for each parameter set in the flow measurement, in that phase values of the pre-measurement which is implemented with the flow coding sequence with the respective parameter set are analyzed. Those parameters of the flow measurement at which the dimension of the phase error is smallest are automatically determined.

Abstract: A method for performing motion compensation in a series of magnetic resonance (MR) images includes acquiring a set of MR image frames spanning different points along an MR recovery curve. A motion-free synthetic image is generated for each of the acquired MR image frames using prior knowledge pertaining to an MR recovery curve. Each of the acquired MR images is registered to its corresponding generated synthetic images. Motion within each of the acquired MR image is corrected based on its corresponding generated synthetic image that has been registered thereto.

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: A shortened version of the MOLLI sequence (Sh-MOLLI) is described which generates rapid and high-resolution myocardial spin-lattice (T1) maps. The Sh-MOLLI technique is based on a significant abbreviation of pre-existing TI sampling scheme combined with the use of processing logic to bypass the major side effects of the above sampling scheme abbreviation and distinguish between long and short T1 relaxation times in order to conditionally utilize available TI samples for non-linear T1 fitting.

Abstract: An MR magnetic field inhomogeneity compensation system acquires multiple MR data sets representing luminance intensity values of individual image elements comprising corresponding multiple different image versions of at least a portion of a first imaging slice of patient anatomy including fat and water components. The compensation system employs the multiple MR data sets in solving corresponding multiple simultaneous nonlinear equations to calculate local frequency offset associated with magnetic field inhomogeneity at the individual image element location, for an individual image element of the image elements. The local frequency offset comprises a difference between proton spin frequency at the location and a nominal proton spin frequency. The compensation system derives data representing an electrical signal to be applied to magnetic field generation coils to substantially compensate for determined offset frequencies at the plurality of individual locations.

Abstract: In a method and magnetic resonance apparatus to acquire and present calibration images of a periodically moving organ with the use of magnetic resonance technology, calibration images are acquired by acquiring measurement data for multiple calibration images during one continuous period of the organ movement, the multiple calibration images differing in their offset frequency and/or in their spatial position in the organ to be examined, and the calibration images in a presentation manner that, from the visual quality of the respective images, allows the user to select (identify) the image acquired with the offset frequency that should then be used to acquire the diagnostic image are displayed to a user.

Abstract: In a magnetic resonance (MR) device and method to determine a background phase curve in MR image data, in first MR image data and in second MR image data that respectively represent different segments (for example different slices) of an examination subject, first and second pixels are identified that represent essentially stationary tissue, and the associated phase values are determined. Phase correction values for the first MR image data are determined depending on the phase values determined for the first and second pixels that represent essentially stationary tissue.

Abstract: In a method and apparatus for MR imaging, a data acquisition sequence is executed wherein at least two slices of an examination subject are imaged in parallel with a gradient echo method for spatially resolved quantification of the T1 relaxation time. At least one first acquisition sequence is implemented to acquire MR data from a first slice of the examination subject and at least one second acquisition sequence is implemented to acquire MR data from a second slice of the examination subject. The acquisition sequences each include an inversion pulse and at least two successive readout steps. The first and second acquisition sequences are temporally offset from one another such that they at least partially overlap.

Abstract: In a method and a device for phase-sensitive flow measurement of a volume segment of an examination subject in a measurement system, the volume segment is divided into multiple partial volume segments and the following steps are executed repeatedly until the volume segment has been completely measured: movement of a table such that a center of one of the partial volume segments to be measured essentially corresponds to the isocenter of the magnetic resonance system, and implementation of the phase-sensitive flow measurement for the partial volume segment to be measured while the center of the partial volume segment essentially corresponds to the isocenter.

Abstract: In a method and a device for phase-sensitive flow measurement of a volume segment of an examination subject using a magnetic resonance (MR) system, the volume segment is coded for imaging of this volume segment and a phase coding of the volume segment to code flow information of the volume segment is implemented. MR data are read out from the volume segment and the MR data are evaluated in order to generate an image of the volume segment with flow information. The phase coding to code the flow information is thereby independent of gradients which are used for spatial coding of the volume segment.

Abstract: A method of deriving blood flow parameters from a moving three-dimensional (3D) model of a blood vessel includes determining a reference vascular cross-sectional plane through a location of a lumen in a moving 3D model of the blood vessel at one time within the model, determining a plurality of target vascular cross-sectional planes at multiple times via temporal tracking of the reference plane based on a displacement field, determining a plurality of contours based on an intersection of the target vascular cross-sectional planes with the moving 3D vessel model at multiple times within the model, and determining a blood flow parameter of the vessel from intersections of each contour of a given one of the times with a phase contrast magnetic resonance (PC-MRI) image of the blood vessel from the corresponding time.

Abstract: In a method and magnetic resonance (MR) system to determine an MR relaxation time (for example a T1, T2 or T2* relaxation time) in the heart muscle in a magnetic resonance examination, a determination an annular slice image region of the heart muscle of the left heart chamber in MR image data with the use of an automatic image segmentation. Multiple sub-regions within the slice image region are automatically determined. Each sub-region respectively includes multiple pixels of the annular slice image region of the heart muscle of the left heart chamber. An MR relaxation time is determined automatically for each of the multiple sub-regions and associated with the corresponding sub-region. A characteristic MR relaxation time in the heart muscle is determined by a statistical analysis of the multiple MR relaxation times that are associated with the multiple sub-regions.

Abstract: In a method of a magnetic resonance system and a method and computer-readable storage medium for the operation thereof to acquire magnetic resonance image data of an examination subject, wherein magnetic resonance system has a number of subsystems and a control device, a number of adjustment measurements to adjust at least one subsystem for making a medical diagnostic data acquisition are implemented through the control device. In these adjustment measurements, an adjustment volume associated with the appertaining adjustment measurement is taken into account that encompasses at least one region of a body containing the examination subject. For this purpose, markings established by the control device within image data of the examination subject and characterizing the spatial occupation (position and orientation) and/or a dimension of the examination subject are determined.

Abstract: For imaging a volume segment by means of a magnetic resonance system, of the volume segment is transferred into a dynamic steady state relative to the magnetization by means of the magnetic resonance system. The following steps are repeatedly executed until the volume segment has been completely measured. The slice is excited by means of the magnetic resonance system. MR signals of the slice are read out. The slice is offset in an overlapping manner such that an overlap range is created by the slice before the offset and the slice after the offset, the overlap range being a predetermined percentile of both the slice before the offset and the slice after the offset.

Abstract: In a method for flow measurement with a magnetic resonance system and a correspondingly designed magnetic resonance system angiography measurement data of a volume are obtained within a body to be examined, a vessel is determined depending on a user input by means of the angiography measurement data, dimensions and an orientation of the vessel are automatically determined from the angiography measurement data, a slice geometry for the flow measurement is automatically determined depending on the dimensions and the orientation, and the flow measurement is implemented using the slice geometry.

Abstract: In a method and magnetic resonance system to determine a flow coding for a flow measurement with the magnetic resonance system, in order to determine the optimal flow coding, a flow pre-measurement with multiple different flow codings is conducted within a slice within a body to be examined, each of these codings allowing flow velocities to be detected with a sensitivity dependent on the respective coding. A velocity distribution is generated from the results of this flow pre-measurement by a Fourier transformation. The optimal flow coding for the flow measurement is then determined based on this spectrum.