Patent classifications
G01R33/4838
SYSTEM AND METHOD FOR TIME OF FLIGHT IMAGING WITH A TIGHT SEQUENCE DIAGRAM PATTERN
A Time-of-flight (TOF) MRI scanning method may include: a TOF MRI scan including a first slice selection gradient applied in the Z direction at the same time as an RF pulse being applied to an imaging target; after applying the RF pulse and first slice selection gradient has ended, applying a slice selection encoding gradient and a phase encoding gradient in the Z direction and Y direction respectively; when application of the slice selection encoding gradient and phase encoding gradient ends, applying a readout gradient in the X direction; when application of the readout gradient ends, applying a tracking saturation pulse to the imaging target, and simultaneously applying a second slice selection gradient in the Z direction; when application of the tracking saturation pulse ends, applying a spoiler gradient in the X, Y and/or Z directions of the magnetic field. The method advantageously reduces the TOF MRI scanning time.
Imaging fluid flow into a region of interest
A magnetic resonance imaging system (100) for acquiring magnetic resonance data (141) from an imaging zone (108) includes a memory (134, 136) for storing machine executable instructions (150, 152, 154, 156) and pulse sequence commands (140). The pulse sequence commands cause the magnetic resonance imaging system to provide at least one spatially selective saturation pulse (408, 410) to at least one selected volume (124, 124′) that is at least partially outside of a region of interest (123) and within the imaging zone. The magnetic resonance imaging system performs a non-selective inversion (412) of spins in the region of interest followed by a readout (414) of the magnetic resonance data which is reconstructed (202) into an image (142).
IMAGE REGION LOCALIZATION METHOD, IMAGE REGION LOCALIZATION APPARATUS, AND MEDICAL IMAGE PROCESSING DEVICE
Embodiments of this application disclose methods, systems, and devices for image region localization and medical image processing. In one aspect, a method comprises acquiring three-dimensional images of a target body part of a patient. The three-dimensional images comprise a plurality of magnetic resonant imaging (MRI) modalities. The method comprises registering a first image set of a first modality with a second image set of a second modality. After the registering, image features of the three-dimensional images are extracted. The image features are fused to obtain fused features. The method also comprises determining voxel types corresponding to voxels in the three-dimensional images according to the fused features. The method also comprises selecting, from the three-dimensional images, target voxels having a preset voxel type, obtaining position information of the target voxels, and localizing a target region within the target body part based on the position information of the target voxels.
Method and apparatus for generating a magnetic resonance data record
In a method and apparatus for generating a magnetic resonance data record, at least two excitation cycles are executed, wherein, in each excitation cycle, at least one magnetic resonance signal is recorded, using different phases with a first radio-frequency pulse in two consecutive excitation cycles, with at least one dephasing gradient being applied in an excitation cycle.
Method and system for cardiac motion corrected MR exam using deformable registration
In various embodiments, the present invention teaches methods and related systems for imaging the coronary arteries in high spatiotemporal resolution for the assessment of coronary stenosis. In some embodiments, the method teaches the use of a 3D radial k-space trajectory, continuous acquisition, retrospective cardiac and respiratory self-gating, and non-rigid cardiac and respiratory motion correction to reconstruct any arbitrary cardiac phase with minimal motion artifacts and high image quality.
Shim-dependent spoiler gradients
A method for determining a spoiler gradient of a magnetic resonance (MR) system is provided. At least one shim parameter that defines a shim magnetic field for compensating for B0 magnetic field inhomogeneities in a measurement volume of the MR system is received. As a function of the at least one shim parameter, at least one spoiler parameter that defines a spoiler gradient for canceling out a transverse magnetization is determined. The spoiler gradient is applied together with the shim magnetic field in a measurement of the MR system.
MAGNETIC RESONANCE TOMOGRAPHY SCANNER AND METHOD FOR OPERATING WITH DYNAMIC B0 COMPENSATION
The disclosure relates to a magnetic resonance tomography scanner and to a method for operating the magnetic resonance tomography scanner. The method includes determining a B0 field map. The method further includes determining an excitation of the nuclear spins to be achieved and a spectrally selective excitation pulse for transmission by a transmitter by way of an antenna as a function of the B0 field map. In the method, the excitation pulse is configured here to generate the excitation of the nuclear spins to be achieved in the patient. The excitation pulse is then output by way of the antenna.
Magnetic resonance imaging apparatus and multi-slice imaging method
An MRI apparatus includes imaging control circuitry that performs shimming imaging for collecting a first MR signal, and multi-slice imaging for collecting a second MR signal along with radiation of a non-region-selective prepulse, and processing circuitry that generates static magnetic field distributions of the slices, determines a first center frequency of an RF pulse corresponding to each slice and a second center frequency of the prepulse based on the static magnetic field distribution, and determines an order of slices for collecting the second MR signal in accordance with the first and/or second center frequencies, wherein the imaging control circuitry performs the multi-slice imaging in accordance with the order and the first and second center frequencies.
MAGNETIZATION TRANSFER BASED METRIC FOR CHEMICAL EXCHANGE SATURATION TRANSFER MRI
The present disclosure relates to a medical analysis system (111) for processing magnetic resonance imaging, MRI, data (170) from a target volume (208) in a subject (218). The system (111) comprises a memory (107) for storing machine executable instructions; and a processor (103) for controlling the system (111), wherein execution of the machine executable instructions causes the processor (103) to: determine from the MRI data (103) chemical exchange saturation transfer, CEST, voxel values corresponding to a transfer of saturation between a predefined pool of protons and water protons, the pool of protons having a predefined chemical shift; and weight the CEST values in order to distinguish CEST values of fluid-rich tissues (507) from CEST values of solid tissues (505) in the target volume (208), wherein the fluid-rich tissue comprises an amount of fluid higher than a predefined minimum amount of fluid.
Methods and apparatus for scan time reductions in magnetic resonance imaging using outer volume supression
Methods for fast magnetic resonance imaging (MRI) using a combination of outer volume suppression (OVS) and accelerated imaging, which may include simultaneous multislice (SMS) imaging, data acquisitions amenable to compressed sensing reconstructions, or combinations thereof. The methods described here do not introduce fold-over artifacts that are otherwise common to reduced field-of-view (FOV) techniques.