Patent application number | Description | Published |
20100052675 | System for Image Acquisition With Fast Magnetic Resonance Gradient Echo Sequences - A system uses a three-dimensional spoiled gradient recalled echo sequence for fat suppression with reduced total acquisition time suitable for acquiring image data under breath-hold conditions using a reversed asymmetry during data acquisition on an opposed phase echo. A system reduces RF pulse repetition time in an MR imaging pulse sequence in an MR imaging device. The system includes an RF pulse generator for generating an RF excitation pulse sequence having a pulse repetition interval. A read-out gradient magnetic field generator generates an asymmetric read-out gradient magnetic field having a readout gradient mid-point occurring prior to an RF echo pulse peak. The RF echo pulse peak is received in response to a generated RF excitation pulse. | 03-04-2010 |
20100182007 | ESTABLISHMENT OF PARAMETERS TO ADJUST A MAGNETIC FIELD SHIM FOR A MAGNETIC RESONANCE EXAMINATION OF A PATIENT - A fast, efficient, qualitatively high-grade shim is enabled in a magnetic resonance apparatus and a method to set shim parameters of a magnetic resonance apparatus, to prepare the implementation of a magnetic resonance examination of a patient with an imaging medical magnetic resonance apparatus having a displaceable patient bed, wherein an examination region of the patient that is to be examined is larger than an imaging region of the magnetic resonance apparatus. | 07-22-2010 |
20100194390 | MAGNETIC RESONANCE METHOD AND APPARATUS FOR TIME-RESOLVED ACQUISITION OF MAGNETIC RESONANCE DATA - In a magnetic resonance method and apparatus for time-resolved acquisition of magnetic resonance data in an examination region of a magnetic resonance imaging scanner, an object being examined is placed on a table and is continuously moved through the examination region, magnetic resonance signals are acquired from the examination region while the object being examined is continuously moved with the table through the examination region and prior to the acquisition of magnetic resonance signals, a phase coding that corresponds to a position in k-space, for the purpose of sampling k-space, is carried out. An interruption of the movement of the table takes place at a predetermined table position, and the acquisition of magnetic resonance signals from an examination region is continued over the course of a predetermined time period, while the table ( | 08-05-2010 |
20120019246 | METHOD FOR MAGNETIC RESONANCE IMAGING BASED ON PARTIALLY PARALLEL ACQUISITION (PPA) - In a method and system for magnetic resonance imaging of an examination subject on the basis of partially parallel acquisition (PPA) with multiple component coils, a calibration measurement is implemented in a first time period and an actual measurement for the imaging is implemented in a subsequent second time period. In the calibration measurement, calibration data for predetermined calibration points in spatial frequency space are acquired with the multiple component coils. In the actual measurement, incomplete data sets are respectively acquired in spatial frequency space with each of the multiple component coils. Complete data sets are reconstructed from the incomplete data sets and the calibration data. The first time period and the second time period are different, and the measurements are implemented when triggered in the two time periods. An essentially identical state of the examination subject or of the measurement system is used as a trigger. | 01-26-2012 |
20120203099 | METHOD AND APPARATUS FOR LOCALIZATION OF INTRODUCED OBJECTS IN INTERVENTIONAL MAGNETIC RESONANCE - In a method and a magnetic resonance system to show an object that is introduced into an examination region, the object having a known chemical shift relative to tissue that is predominant in the examination region, magnetic resonance signals are acquired from the examination region of the subject with the introduced object therein, and the different chemical shift of the introduced object and of the predominant tissue is computationally used in a processor to calculate, from the acquired magnetic resonance signals, a localization image in which substantially only the introduced object is shown. | 08-09-2012 |
20130076352 | METHOD TO SELECT AN UNDERSAMPLING SCHEME FOR MAGNETIC RESONANCE IMAGING, AND MAGNETIC RESONANCE IMAGING METHOD AND SYSTEM USING SUCH A SELECTED UNDERSAMPLING SCHEME - In a method to select an undersampling scheme of k-space and an associated set of reconstruction kernels to acquire reduced magnetic resonance (MR) data sets with multiple coils, a calibration data set is acquired for each of the respective coils, a noise covariance is determined from autocorrelations and correlations of the noise of the various coils. At least one set of reconstruction kernels is calculated for each of the multiple undersampling schemes from the calibration data sets of the various coils. For each set of reconstruction kernels, a characteristic value is calculated from the noise covariance and the respective reconstruction kernels of the coils, with the characteristic value being proportional to a spatial mean value of a signal noise of an MR image. A selected undersampling scheme and a selected set of reconstruction kernels are selected based on the calculated characteristic values. | 03-28-2013 |
20140062479 | MAGNETIC RESONANCE METHOD AND APPARATUS FOR GENERATING AN IMAGE OF A SUBJECT WITH TWO SPIN SPECIES - In a method and apparatus to determine a magnetic resonance image of an examination subject with at least two spin species by using a chemical shift imaging multi-echo MR measurement sequence, first approximated MR image is determined based on a first approximative model and of a second approximated MR image is determined based on a second approximative model, wherein the first and second approximative model respectively express an MR signal under consideration of one or more MR parameters, and wherein the first and second approximative model differ with regard to the consideration of at least one MR parameter. The MR image is determined from a mean calculation that depends on the first and second approximated MR image. | 03-06-2014 |
20140125336 | Adaptive and Interactive Assessment of Tissue Properties in MR Imaging - Embodiments relate to evaluating properties of tissues with magnetic resonance imaging (MRI). A MR image is used to measure a characteristic that influences a particular chemical property of a tissue. In an exemplary embodiment, tissue transverse relaxation values or relaxation rates, which can readily be measured from MR images, are used to evaluate iron deposition in tissue. Iron deposition influences the tissue transverse relaxation values (T | 05-08-2014 |
20140126795 | FAT AND IRON QUANTIFICATION USING A MULTI-STEP ADAPTIVE FITTING APPROACH WITH MULTI-ECHO MAGNETIC RESONANCE IMAGING - A computer-implemented method for quantifying fat and iron in anatomical tissue includes acquiring a plurality of multi-echo signal datasets representative of the anatomical tissue using a magnetic resonance (MR) pulse sequence. A plurality of multi-echo signal datasets are selected from the plurality of multi-echo signal datasets and used to determine a first water magnitude value and a first fat magnitude value. In response to determining that the multi-echo signal datasets include at least three multi-echo datasets, a first stage analysis is performed. This first stage analysis comprises selecting a first effective transverse relaxation rate value. Next, first algorithm inputs comprising the first water magnitude value, the first fat magnitude value, and the first effective transverse relation rate value are created. Then, a non-linear fitting algorithm is performed based on the first algorithm inputs to calculate a second water magnitude value, a second fat magnitude value, and a second effective transverse relaxation rate value. A first proton density fat fraction value is then determined based on the second water magnitude value and the second fat magnitude value. | 05-08-2014 |
20140161336 | Dynamic Adaptation of a Degree of Signal Compression for MRT Image Processing - An apparatus and a method for generating an image from N reception signal data sets of signals received by a plurality of coils of a magnetic resonance tomography appliance from a region of a body to be examined using an image processing computer are provided. The apparatus includes a degree-of-compression determining device. A ratio N/M of the number N of N reception signal data sets generated from the signals received by the plurality of coils to a smaller number M of mode data sets is defined taking account of a plurality of parameters. The plurality of parameters at least also represent system resources of the image processing computer. Using a compression computer, the N reception signal data sets are compressed into M mode data sets. After this, the M mode data sets are used by the image processing computer for generating the image of the region of the body. | 06-12-2014 |
20150042334 | METHOD AND MAGNETIC RESONANCE SYSTEM TO DETERMINE THE T1 TIME OF WATER AND THE T1 TIME OF FAT - In a method and a magnetic resonance system to determine the T1 time of water and the T1 time of fat in a predetermined volume segment of an examination subject, magnetic field gradients are activated to generate multiple gradient echoes. First echoes are acquired at at least two different echo times based on RF pulses with a first flip angle. A first water magnetization and a first fat magnetization are determined for each voxel of the volume segment from the first echoes, according to the Dixon method. Second echoes are acquired at at least two different echo times based on RF pulses with a second flip angle. A second water magnetization and a second fat magnetization are determined for each voxel of the volume segment depending on the second echoes according to the Dixon method. The T1 time of water and the T1 time of fat for each voxel are determined depending on the first water magnetization of the respective voxel, the first fat magnetization of the respective voxel, the first flip angle, the second water magnetization of the respective voxel, the second fat magnetization of the respective voxel, and the second flip angle. | 02-12-2015 |
20150061672 | METHOD AND APPARATUS FOR MAGNETIC RESONANCE DATA ACQUISITION USING A MULTIPOINT DIXON TECHNIQUE - In a method and magnetic resonance (MR) apparatus to acquire MR data from a subject, a predetermined spectral model of a multipoint Dixon technique is used that includes at least two spectral components with respective associated relaxation rates, a first phase due to field inhomogeneities; and a second phase due to eddy current effects. MR data are acquired using a bipolar multi-echo MR measurement sequence for multiple image points wherein, for each image point, the multi-echo MR measurement sequence alternately uses positive and negative readout gradient fields for the readout of MR signals of the MR data at at least three echo times. The at least two spectral components are determined based on the MR data. | 03-05-2015 |