Patent application number | Description | Published |
20100268061 | MAGNETIC RESONANCE METHOD AND APPARATUS USING DUAL ECHOES FOR DATA ACQUISITION - In a method and system for acquiring magnetic resonance image data from a subject, using a data acquisition unit in which a basic magnetic field is generated, a division is designated in a planar section through the subject that divides the planar section into a first section and a second section, with the homogeneity of the basic magnetic field being better in said first section than in said second section. An echo planar imaging sequence is implemented to acquire the magnetic resonance imaging data, with magnetic resonance data being acquired from the first section only from gradient echo signals in the echo planar imaging sequence, and magnetic resonance data from said the second section being acquired from both gradient echo signals and spin echo signals in the echo planar imaging sequence. The method and apparatus are particularly suited for acquiring functional magnetic resonance imaging (fMRI) data from the brain of a subject, in which the first section is an upper portion of the brain and the second section is a lower portion of the brain. | 10-21-2010 |
20110187367 | METHOD AND MAGNETIC RESONANCE SYSTEM TO REDUCE DISTORTIONS IN DIFFUSION IMAGING - In a method and magnetic resonance apparatus to reduce distortions in magnetic resonance diffusion imaging, a magnetic resonance data acquisition system is operated to acquire magnetic resonance data in a first measurement with a first diffusion weighting, and to acquire magnetic resonance data in a second measurement with a second, different diffusion weighting. A non-linear, system-specific distortion-correcting function is determined on the basis of system-specific information that is specific to said magnetic resonance data acquisition system. Correction parameters are calculated to correct distortions in subsequently-acquired diffusion-weighted magnetic resonance images, based on the data acquired in the first and second measurements with the system-specific distortion-correcting function applied thereto. The subsequently-acquired diffusion-weighted magnetic resonance images are corrected using the correction parameters to at least reduce distortions therein. | 08-04-2011 |
20110241679 | MAGNETIC RESONANCE METHOD AND APPARATUS TO REDUCE DISTORTIONS IN DIFFUSION IMAGES - In a method and apparatus to reduce distortions in diffusion imaging, at least one first measurement is implemented with a first diffusion weighting for a number of slices that are spatially separated from one another and at least one second measurement is implemented with a second diffusion weighting for the number of slices that are spatially separated from one another. A deskewing function is determined as are correction parameters to deskew diffusion-weighted magnetic resonance images on the basis of the measurements, so that image information and/or correction parameters of different slices are linked with one another. The diffusion-weighted magnetic resonance images are distortion-corrected on the basis of the deskewing function and the correction parameters. | 10-06-2011 |
20120025825 | METHOD AND MAGNETIC RESONANCE APPARATUS FOR DYNAMIC PHASE CORRECTION IN A MULTI CHANNEL RF TRANSMISSION - In a method and magnetic resonance (MR) apparatus to acquire spin echo-based MR signals of an examination subject with a multi-spin echo sequence with multiple refocusing pulses after a single excitation pulse in an MR system that has a multichannel RF transmission and reception module: detect a spatial, two-dimensional phase distribution in the examination subject is detected by acquiring navigator signals, a phase and amplitude distribution for the individual transmission channels of the RF transmission and reception module is calculated to generate a magnetic field B | 02-02-2012 |
20120259199 | MAGNETIC RESONANCE SYSTEM AND METHOD TO GENERATE DIFFUSION INFORMATION - In a magnetic resonance (MR) method and system for the generation of diffusion information, diffusion-weighted MR images of an examination subject are generated, each image being generated using an individual diffusion gradient. The diffusion gradients, and therefore the MR images, are sorted such that, after the sorting, a predefined number of diffusion gradients respectively forms a group. Each diffusion gradient belongs to at least one of these groups, and the diffusion gradients of the respective same group are all as linearly independent of one another as possible. The MR images whose diffusion gradients form a group are assembled into an MR result image. Spatial transformations between the MR result images are determined, and the MR images are modified using these spatial transformations. The diffusion information is formed with the aid of the modified MR images. | 10-11-2012 |
20120286777 | DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING USING 3D MOSAIC SEGMENTATION AND 3D NAVIGATOR PHASE CORRECTION - In a magnetic resonance apparatus and operating method therefore, 3D navigator data are acquired and are used to correct spatially varying phase errors in contemporaneously acquired imaging data in each shot of a multi-shot data acquisition sequence. A mosaic sampling scheme is used to enter the diffusion-weighted magnetic resonance data and the navigator data into k-space respectively in blocks that each form a subset of the entirety of k-space. The navigator data in each shot are entered into a block that is located at the center of k-space, and, in each shot, the corresponding image data are entered into an offset block in k-space, that is offset in at least one spatial direction from the navigator data block. The offset is varied from shot-to-shot. | 11-15-2012 |
20130033262 | METHOD TO GENERATE MAGNETIC RESONANCE EXPOSURES - In a method described for generating magnetic resonance exposures in which diffusion-coded raw data are acquired with of a diffusion gradient measurement sequence having a number of partial diffusion gradient sequences, at least one diffusion coding gradient pulse is emitted in each partial data set, and raw data of a k-space region are acquired during a first echo after a defined first echo time the k-space regions in total covering a complete k-space. Raw data of an established navigator k-space region are acquired during a second echo after a second echo time the navigator k-space region being identical for different partial diffusion gradient sequences. Reference raw data are acquired by a reference measurement sequence with multiple partial reference sequences. | 02-07-2013 |
20130221965 | B1 Field-Based Regulation Within a Sequence for NMR - A B1 magnetic field may be regulated during a magnetic resonance tomography (MRT) imaging sequence. | 08-29-2013 |
20140091790 | METHOD AND MAGNETIC RESONANCE SYSTEM FOR TIME-DEPENDENT INTENSITY CORRECTION OF DIFFUSION-WEIGHTED MR IMAGES - In a method and magnetic resonance (MR) apparatus for time-dependent intensity correction of diffusion-weighted MR images that are acquired with a sequence of different diffusion gradient fields, different diffusion gradient fields are associated with at least one group, with the association with groups being established so that the diffusion gradient fields that are associated with the same group satisfy an orthogonality criterion. For each group, an MR result image is created from the MR images associated with the group, such that the MR result image has a suppressed direction dependency of the diffusion weighting in comparison to the constituent MR images. An intensity correction can be made based on the multiple MR result images and used to correct the constituent MR images. | 04-03-2014 |
20140197834 | METHOD AND MAGNETIC RESONANCE APPARATUS FOR ECHO PLANAR IMAGING WITH DATA ENTRY INTO K-SPACE ALONG A ZIGZAG TRAJECTORY - In a method and apparatus for echo planar magnetic resonance (MR) imaging sequence of phase encoding gradient fields and a sequence of readout gradient fields are applied in order to produce a well-defined zigzag-type trajectory for entering raw data into k-space. Zigzag-type trajectories can be achieved that have flanks without curvature, or without significant curvature. Cartesian methods for image reconstruction of parallel MR imaging are applied to echo planar MR imaging with such zigzag-type trajectories. | 07-17-2014 |
20150084629 | METHOD AND MAGNETIC RESONANCE SYSTEM FOR ACQUIRING MAGNETIC RESONANCE DATA - In a method for acquiring magnetic resonance data with a magnetic resonance system using a magnetic resonance sequence, the sequence has a first partial sequence in which magnetic resonance data are acquired for multiple slices that have to be acquired simultaneously, from which image data for the individual slices are calculated by a reconstruction algorithm. The sequence also has a second partial sequence for determining additional data, which are used to evaluate and/or assess the magnetic resonance data, and which have a spatial resolution that is lower than the magnetic resonance data, in which radio-frequency pulses and readout processes take place in a slice-specific manner through a time offset within a single measuring process, in which a single continuous excitation period with the radio-frequency pulses and a single continuous readout period with the readout processes follow one another, so that separate additional data are directly determined for each slice. | 03-26-2015 |