Patent classifications
G01R33/4838
MAGNETIC RESONANCE APPARATUS AND METHOD FOR DYNAMIC ADJUSTMENT THEREOF WITH MULTIPLE ADJUSTMENT PARAMETERS
In a method and magnetic resonance (MR) apparatus for performing an adjustment of the MR system, an examination object under is divided into at least one excitation volume. First adjustment parameters for the at least one excitation volume of the object, and second adjustment parameters for the at least one excitation volume of the object, which differ from the first adjustment parameters are determined. First MR signals are acquired from the at least one excitation volume using the first adjustment parameters. Second MR signals are acquired from an excitation volume using the second adjustment parameters. A first MR image of the at least one excitation volume is reconstructed using the first MR signal. A second MR image of the at least one excitation volume is reconstructed using the second MR signal.
Method for reduced field of view MRI in an inhomogeneous field with rapid outer volume suppression
An MRI scanner may include one or more gradient waveform generators, gradient amplifiers, gradient coils, an RF waveform generator, an RF amplifier, an RF coil, a superconducting magnet, an RF detector; a digitizer, and a computer system that controls the one or more gradient waveform generators and the RF waveform generator so as to generate a magnetization saturation preparation pulse sequence that includes a tip-down pulse that is insensitive to RF field inhomogeneity followed by a tip-back pulse that employs a conjugate symmetry constraint in its energy spectrum.
Control and data signaling in SC-FDMA communication systems
An apparatus and method are provided for transmitting control information and data in an SC-FDMA communication system. The method includes placing a reference signal onto one middle symbol among a plurality of symbols in one slot, wherein the one slot is one of two slots in one subframe; placing CQI information onto at least one symbol of other symbols except for the one middle symbol; placing the data onto the other symbols except for the one middle symbol; placing a HARQ-ACK onto two symbols, wherein the two symbols are directly adjacent to the one middle symbol; and transmitting a signal including the reference signal, the data, the CQI information, and the HARQ-ACK. The HARQ-ACK is placed onto a position of at least part of the data. The symbols are SC-FDMA symbols, the one middle symbol is a 4th symbol, the two symbols are a 3rd symbol and a 5th symbol.
Method for non-contrast enhanced magnetic resonance angiography
A method for performing a non-contrast-enhanced magnetic resonance angiography (“MRA”) for a subject is provided. The method includes directing a magnetic resonance imaging (“MRI”) system to perform a pulse sequence to acquire k-space data from imaging slices that are oriented away from an axial direction of the subject. The method includes repeating the pulse sequence for a plurality of imaging slices, wherein a field-of-view (“FOV”) of at least one of the plurality of imaging slices is shifted by a predetermined value. The method also includes reconstructing, using the acquired k-space data, one or more angiographic images indicative of the subject's vasculature.
METHOD AND APPARATUS FOR IMAGING A JAW REGION
The disclosure relates to a technique for providing an image of diagnostically relevant area of a jaw region of a patient by means of a magnetic resonance apparatus by capturing information about the jaw region of the patient, which comprises at least one reference to a position and/or an extent of the diagnostically relevant area of the jaw region. The technique also includes adjusting a parameter of a magnetic resonance measurement as a function of the captured information about the jaw region of the patient, carrying out the magnetic resonance measurement with the adjusted parameter, capturing image data of the jaw region of the patient, reconstructing an image of the diagnostically relevant area of the jaw region as a function of the captured image data, and providing the image of the diagnostically relevant area of the jaw region of the patient.
Magnetic resonance method and apparatus wherein signal contributions outside of the measurement region are reduced
In magnetic resonance imaging using a measurement sequence of the “free precession of transverse magnetization in the steady state”-type i.e., an SSFP measurement sequence, during the SSFP measurement sequence, the implementation of a preparation sequence takes place to reduce a signal contribution of the transverse magnetization in an outer region surrounding a measurement region in the MR imaging. The implementation of the preparation sequence includes the radiation of a multidimensional, spatially selective RF pulse that acts in a spatially selective manner on the transverse magnetization in the outer region. Saturation of the transverse magnetization and/or dephasing of the transverse magnetization in the outer region can be achieved by the multidimensional, spatially selective RF pulse.
MAGNETIC RESONANCE IMAGING METHOD
A magnetic resonance imaging method executed in a magnetic resonance imaging apparatus according to an embodiment comprises: applying an inversion pulse; executing a subsequent imaging sequence including an RF (Radio Frequency) pulse and a gradient magnetic field concurrently applied with the RF pulse in a slice direction and performing, for a slice position selected by the RF pulse and the gradient magnetic field and during a time period including a null point, data acquisition in a plurality of orientations including a center of a two-dimensional k-space.
Magnetic resonance imaging apparatus
A magnetic resonance imaging apparatus according to an embodiment includes a controller and a generator. The controller divides a plurality of slice regions that are sequentially arranged into a first group including two non-sequential slice regions and a second group including a slice region positioned between the two non-sequential slice regions and acquires data from the slice regions for each of the groups. When acquiring data from at least one of the two non-sequential slice regions, the controller acquires the data after applying a pre-sat pulse to a position between the two non-sequential slice regions. When acquiring data from the slice region positioned between the two non-sequential slice regions, the controller acquires the data after applying a pre-sat pulse to a position of at least one of the two non-sequential slice regions.
Background-Suppressed, Reduced Field-Of-View Radial Magnetic Resonance Imaging
Embodiments relate to a method and system to improve fat suppression and reduce motion and off-resonance artifacts in magnetic resonance imaging (MRI) by using a background-suppressed, reduced field-of-view (FOV) radial imaging. The reduction of such artifacts provides improved diagnostic image quality, higher throughput of MRI scans for the imaging center, and increased patient comfort. By using a small FOV radial acquisition that only encompasses the structures of interest, structures that cause motion artifacts, such as the anterior abdominal wall, bowel loops, or blood vessels with pulsatile flow, are excluded from the image. According to an embodiment, combining a small FOV radial acquisition with one or more background-suppression techniques minimizes the impact of artifacts caused by anatomy outside of the FOV.
MAGNETIC RESONANCE IMAGING APPARATUS
A magnetic resonance imaging apparatus according to an embodiment includes processing circuitry. The processing circuitry performs at least one of data collection for collecting first data of an imaging region of a subject at a plurality of time intervals after a tag pulse is applied to fluid flowing into the imaging region, and data collection for collecting second data of the imaging region by differing at least one of applying or not-applying the tag pulse and a position of the applying. The processing circuitry performs phase correction for at least one of the first data and the second data by using data in which the longitudinal magnetization of the fluid is a positive value, to generate an image for each time phase.