Patent classifications
G01R33/56308
Magnetic resonance imaging apparatus and magnetic resonance imaging method
A magnetic resonance imaging apparatus according to an embodiment includes sequence control circuitry and processing circuitry. The sequence control circuitry executes a first pulse sequence and a second pulse sequence, the first pulse sequence including a first spoiler pulse serving as a dephasing gradient pulse of a first amount, the second pulse sequence including a second spoiler pulse serving as a dephasing gradient pulse of a second amount being different from the first amount or the second pulse sequence not including a spoiler pulse serving as a dephasing gradient pulse. The processing circuitry performs a subtraction operation between a first data obtained from the first pulse sequence and a second data obtained from the second pulse sequence, thereby generating an image.
Cartesian sampling for dynamic magnetic resonance imaging (MRI)
A variable density Cartesian sampling method that allows retrospective adjustment of temporal resolution, providing added flexibility for real-time applications where optimal temporal resolution may not be known in advance. The methods provide for a computationally efficient sampling methods where a first step includes producing a uniformly random sampling pattern using a golden ratio on a grid, and the second step is applying a nonlinear stretching operation to create a variable density sampling pattern. Diagnostic quality images may be recovered at different temporal resolutions.
MAGNETIC RESONANCE IMAGING APPARATUS, IMAGE PROCESSING APPARATUS, AND IMAGE PROCESSING METHOD
A magnetic resonance imaging apparatus captures a morphology image and a function image that are captured with respect to an equal imaging region of an object under examination. Processing for deforming the morphology image is performed using a deformation parameter and moving positions of structural objects included in the morphology image to respective positions of structural objects of a previously determined standard morphology. Then, the function image is deformed using a value of the deformation parameter used in deforming the morphology image to cause a position of a region included in the function image to coincide with a position of a corresponding region of the standard morphology or by using the standard morphology in an opposite direction using the value of the deformation parameter to cause a position of a region of the structural object thereof to coincide with a position of a corresponding region included in the function image.
MAGNETIC RESONANCE IMAGING APPARATUS, MAGNETIC RESONANCE IMAGING METHOD, AND COMPUTER PROGRAM PRODUCT
A magnetic resonance imaging apparatus according to an embodiment includes sequence control circuitry and processing circuitry. The sequence control circuitry performs multi-frame acquisition where FOVs (Field Of Views) of at least two acquired frames are overlapped in a first direction. Then, based on the multi-frame acquisition performed by the sequence control unit, the processing unit generates data regarding the components in the first direction of flow of a fluid.
Acoustic radiation force imaging
An apparatus includes a high intensity focused ultrasound (HIFU) system and a magnetic resonance (MR) imaging system. A memory stores: instructions, pulse sequence commands for an acoustic radiation force imaging protocol, and first and second sonication commands. The pulse sequence commands specify acquisition of the MR data for first and second pulse sequence repetitions. The pulse sequence commands specify for each of the sequence repetitions a first and a second group of motion encoding gradients. Execution of the instructions causes a processor to: acquire first and second MR data by controlling the MR imaging system with the pulse sequence commands and by controlling the HIFU system with the first and second sonication commands, respectively; reconstruct first and second motion encoded images from the first and second MR data, respectively; and construct a displacement map from the difference of the first and second motion encoded images.
DYNAMIC MAGNETIC RESONANCE ANGIOGRAPHY METHOD AND SYSTEM
A dynamic magnetic resonance angiography, MRA, method, comprising: acquiring, by an MR scanning device, a multi-contrast magnetic resonance, MR, sequence of a portion of a body; identifying, by a processing circuit, blood vessels of the portion by identifying blood of the portion based on predetermined characteristic of blood and the multi-contrast MR sequence; generating, by the processing circuit, a first MRA image frame and a second MRA image frame, based on the multi-contrast MR sequence, respectively visualising a first part and a second part of the identified blood vessels; generating, by the processing circuit, a dynamic MRA image for visualising a dynamic blood flow through a part of the portion, based on the first and second MRA image frame.
HAEMODYNAMIC DATA ESTIMATION
Techniques exist for measuring local blood velocity of flow rate waveforms in, for example, mammalian vascular segments. A method and system for deriving information on disease in vascular segments, for example mean pressure, drop in mean pressure and/or hydraulic resistance, from such measured waveforms is described. The waveforms can, for example, be measured non-invasively using Doppler ultrasound or magnetic resonance techniques. Form factors (Vff, Pff) for the velocity waveform and the central arterial pressure as determined. Stenosis may be detected by detecting changes, e.g, in Vff/Pff.
Method for detecting the movement of a temporomandibular joint
Described is a method for detecting and displaying the movement of a temporomandibular joint which connects a lower jaw and an upper jaw by magnetic resonance imaging. A marker is secured to the lower jaw, a marker movement curve is generated using magnetic resonance imaging measurement data sets during a first measurement interval, during which the lower jaw is moved relative to the upper jaw, and a point which corresponds to a first position of the lower jaw relative to the upper jaw is ascertained on the movement curve. An image data set is generated during a second measurement interval, during which the temporomandibular joint is not moved, and a first model, which represents at least one part of the upper jaw and/or a temporal bone part that comprises the temporomandibular joint socket, and a second model, which represents at least one part of the lower jaw, are ascertained therefrom. A movement curve of the second model relative to the first model is calculated and displayed using the marker movement curve.
Dynamic imaging based on echo planar imaging sequence
Methods, devices, systems and apparatus for dynamic imaging based on echo planar imaging (EPI) sequence are provided. In one aspect, a method includes: obtaining first pre-scanned k-space data by performing a pre-scan for a subject based on a first EPI sequence and pre-scanning parameters, obtaining a pre-scanned image and second pre-scanned k-space data according to the first pre-scanned k-space data, performing a dynamic scan for the subject based on a second EPI sequence and dynamic scanning parameters to generate dynamically-scanned k-space data associated with each of a plurality of dynamic periods in the dynamic scan, and for each of the dynamic periods, generating a residual image according to the dynamically-scanned k-space data of the dynamic period and the second pre-scanned k-space data, and adding the pre-scanned image and the residual image to obtain a dynamic image of the dynamic period.
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).