Abstract: A method, a computer program product and a computer-readable storage medium are disclosed for displaying signal values of a combined magnetic resonance positron emission tomography device. In at least one embodiment, the spatial correspondence of signal values, which result from a magnetic resonance measurement, and of signal values, which result from a positron emission tomography measurement, are used and the corresponding signal values are arranged in matrix form and displayed graphically as a multi-dimensional scatter plot.

Abstract: In a medical image acquisition, and operating method, before acquiring a current planning image data set from a subject, a statistical atlas is generated from multiple planning image data sets using a specific measurement protocol, as a statistical compilation including an average image data set electronically associated with association information that identifies different anatomical entities represented by the statistical compilation. After the current planning image data set is acquired, the stored average image data set is transformed into the current planning image data set, with the association information being accurately associated with the current planning image data set. A diagnostic image acquisition of the subject is then controlled using the association information that is now associated with the current planning image data set.

Abstract: A method is disclosed for generating a motion-corrected PET image of an examination area in a combined MR-PET system. In an embodiment, the method includes recording PET events from the examination area in a first recording time frame; recording a number of MR images of the examination area in at least the first recording time frame; calculating an at least two-dimensional movement information of the examination area on the basis of the number of MR images, wherein the movement information describes the movement information of the examination area during the first recording time frame, and determining the motion-corrected PET image from the PET events using the calculated movement information.

Abstract: A phantom, particularly for use in MR- or PET-based imaging methods, includes a hollow base body that delimits an interior volume, wherein the interior volume is subdivided into at least two volume portions by at least one separation element, and wherein the separation element or a section thereof consists of foam.

Abstract: A method is disclosed for imaging a portion of an examination object in a magnetic resonance scanner. The portion is arranged at the edge of a field of view of the magnetic resonance scanner. During at least one embodiment of the method, a gradient field is produced such that a nonlinearity in the gradient field and a B0-field inhomogeneity cancel at a predetermined point at the edge of the field of view. Magnetic resonance data, which contains the predetermined point at the edge of the field of view, is acquired with the aid of the gradient field. An image of the portion of the examination object at the predetermined point is determined from the magnetic resonance data.

Abstract: A method, a computer program product and a computer readable storage medium are disclosed for generating a global attenuation map used for attenuation correction of positron emission tomography image data sets in a combined magnetic resonance-positron emission tomography device. In an embodiment, during the course of detecting hardware components of the combined magnetic resonance-positron emission tomography device and determining positions of the detected hardware components relative to a patient support, the global attenuation map is generated as a function of the detected hardware components.

Abstract: A method of attenuation correction for a positron emission tomography (PET) system includes obtaining PET scan data representative of a volume scanned by the PET system, obtaining a plurality of magnetic resonance (MR) scan data sets representative of the volume, each MR scan data set being acquired in a respective time period during acquisition of the PET scan data by the PET system, detecting motion of the volume that occurred during the acquisition of the PET scan data based on an assessment of the plurality of MR scan data sets, the PET scan data, or the plurality of MR scan data sets and the PET scan data, determining attenuation correction data from the plurality of MR scan data sets based on the detected motion for alignment of the attenuation correction data and the PET scan data, and correcting the PET scan data with the attenuation correction data.

Abstract: A method is disclosed for determining a location of a subarea of an area under examination in a magnetic resonance system. The subarea is arranged at the edge of a field-of-view of the magnetic resonance system. In at least one embodiment of the method, at least one slice position is determined for an MR image in which the B0 field at the edge of the MR image satisfies a homogeneity value. For the slice position determined an MR image is acquired which contains the subarea at the edge of the field-of-view and the location of the subarea of the object under examination is determined through the location of the subarea in the MR image.

Abstract: Various embodiments relate to a method for the movement-averaged attenuation correction of positron emission tomography data based on magnetic resonance tomography data. In at least one embodiment, the method includes capturing of multiple MRT data respectively in different phases of a cycle of an anatomical disposition of an investigation subject. The method furthermore includes respectively for each of the plurality of MRT data: determination of a value of an attenuation parameter via segmentation and averaging of the determined values of the attenuation parameter in order to obtain an averaged value of the attenuation parameter. The method furthermore includes the execution of attenuation correction of the PET data based on the averaged value of the attenuation parameter.

Abstract: To carry out magnetic resonance (MR) tomography, a physiological parameter of an object to be examined is acquired as a function of time to detect a physiological cycle which repeats itself over time. First MR data is acquired for a first region, wherein all points of the first region are arranged in a region of a field of view of an MR system. Acquisition of the first MR data occurs selectively in first time intervals which are synchronized with the physiological cycle and are separated from each other by waiting intervals. Second MR data is acquired for a second region which adjoins the first region. Acquisition of the second MR data occurs in the waiting intervals between the first time intervals.

Abstract: A method is disclosed for correction of truncations of a magnetic resonance image of an object under examination in the reconstruction of image data from raw data. In at least one embodiment, the method includes determining a number of one-dimensional projections of imaged field of view in the Radon space from the raw data in order to obtain a projection profile; checking each projection profile for whether the projection profile exhibits a truncation; if the respective checked projection profile exhibits a truncation, expanding the projection profile for correcting the truncation in that the projection profile is extrapolated in accordance with a predetermined extrapolation model in the area in which it exhibits the truncation; and reconstructing image data based on the expanded projection profiles in which the truncation of the image of the object under examination is corrected.

Abstract: A method is disclosed for determining radiation attenuation as a result of an object in a positron emission tomography scanner. In at least one embodiment, a phantom object is arranged in the positron emission tomography scanner during the method. First raw radiation data of the phantom object is acquired while the object is not arranged in the positron emission tomography scanner. A first image of the phantom object is calculated from the first raw radiation data. The object then is arranged in the positron emission tomography scanner (2) and preliminary radiation attenuation of the object is identified. Second raw radiation data of the phantom object is acquired while the object is arranged in the positron emission tomography scanner. A second image of the phantom object is calculated from the second raw radiation data taking into account the preliminary radiation attenuation. The radiation attenuation is determined on the basis of the first image and the second image.

Abstract: Various embodiments relate to a method of attenuation correction of Positron Emission Tomography (PET) data based on Magnetic Resonance Tomography (MRT) data. A method of at least one embodiment further includes determining further data being indicative of an iterative cycle of a physiological observable of a patient and matching the PET data with the MRT data based on the further data.

Abstract: In an embodiment, an initial segmentation of an examination object is fixed, wherein an attenuation coefficient is assigned to each segment of the segmentation. Raw radiation data about the examination object arranged in the positron emission tomography scanner is acquired, and a correction factor is determined for each pixel with the aid of an optimization method, in which the probability of the acquired raw radiation data is maximized taking into account the segmentation and the attenuation coefficients assigned to the segments. A statistical parameter of the correction factors is determined for each segment and the segmentation is corrected by subdividing a segment as a function of the statistical parameter determined for the segment. A segment correction factor is determined for each segment from the correction factors assigned to the segment and the attenuation coefficients assigned to the segments are corrected as a function of the segment correction factors.

Abstract: A method is disclosed for performing a combined magnetic resonance/positron emission tomography scan of an examination object in an MR/PET system. An embodiment of the method entails acquiring first magnetic resonance data using a first readout gradient field. The first readout gradient field is chosen such that, at a location of the field of view of the magnetic resonance system, a distortion caused by a nonlinearity of the first readout gradient field and a distortion caused by a B0 field inhomogeneity substantially cancel each other out. First magnetic resonance images for planning the combined magnetic resonance/positron emission tomography session and determining an attenuation correction map for a positron emission tomography scan are determined on the basis of the first magnetic resonance data. Positron emission data and second magnetic resonance data are acquired using a second readout gradient field.

Abstract: A method is disclosed for calculating a spatially resolved value of an absorption parameter for a positron emission tomography (PET) scan of an examination object via magnetic resonance tomography (MRT). Magnetic resonance data is acquired within a first region lying within a field of view of a magnetic resonance system and within a second region bordering on the first and lying at the edge of the field of view. The method includes the spatially resolved calculation of a first value of the absorption parameter from the first MR data within the first region and of a second value from the second MR data within the second region. A three-dimensional parameter map is obtained from the first value. This parameter map is extended by the second value such that within the first region and the second region the parameter map has the value of the absorption parameter in spatially resolved form.

Abstract: The invention concerns a method to generate an MR image of an examination subject of MR signals of the examination subject being detected with a receiver coil element of a magnetic resonance system. A spatially related sensitivity is determined for the receiver coil element. A mask is generated for the receiver coil element depending on the sensitivity of the receiver coil element in order to therewith mask a region of the MR image, in which region the receiver coil element has at least one predetermined sensitivity. At least one RF excitation pulse and at least one magnetic field gradient are activated to acquire MR data with the receiver coil element, and a preliminary MR image is generated depending on MR data acquired therewith. The mask of the receiver coil element is applied to the preliminary MR image in order to generate an MR image of the receiver coil element, and an MR image of the examination subject is generated from the MR image for the receiver coil element.

Abstract: A method is disclosed for acquiring magnetic resonance (MR) data for a plurality of layers of an object to be examined in a section of a magnetic resonance system having a basic magnetic field, wherein the section is located at the edge of a Field of View of the magnetic resonance system in the first direction. The method includes producing a first gradient field having a non-linearity of its location dependence in such a way that in the section the non-linearity compensates a local inhomogeneity of the basic magnetic field, and then multiple positioning of the object to be examined in a first direction, so the plurality of layers of the object to be examined perpendicular to the first direction successively includes the section. Finally, it includes the acquisition of magnetic resonance data for each of the layers with recording sequences.

Abstract: In a method and magnetic resonance (MR) apparatus to image a partial region of an examination subject by means of a multislice measurement, which partial region includes at least two measurement slices, and is located at least in part at the edge of a field of view of the magnetic resonance apparatus, for each voxel to be optimized that is located at the edge of the field of view, a gradient field is configured for each measurement slice of the partial region that is to be measured and is used to acquire magnetic resonance data in the multislice measurement. The gradient field is configured so as to cause a nonlinearity of the gradient field and a B0 field inhomogeneity to cancel at each of the aforementioned voxel to be optimized at the partial region at the edge of the field of view. An image of the partial region of the examination subject is determined from the magnetic resonance data acquired in this manner.

Abstract: Example embodiments are directed to a method of correcting attenuation in a magnetic resonance (MR) scanner and a positron emission tomography (PET) unit. The method includes acquiring PET sinogram data of an object within a field of view of the PET unit. The method further includes producing an attenuation map based on a maximum likelihood expectation maximization (MLEM) of a parameterized model instance and the PET sinogram data.