G01R33/5608

SYSTEM AND METHOD FOR TISSUE CHARACTERIZATION USING FAST QUANTITATIVE SPIN-LOCK MAGNETIZATION TRANSFER IMAGING
20230236273 · 2023-07-27 · ·

Systems and methods for fast and robust quantification of magnetization transfer (MT) use off-resonance spin-lock MRI with as few as two or three image acquisitions. Each image acquisition can be performed using an off-resonance spin-lock pulse having a different RF amplitude and frequency offset. A parameter representing the difference of the relaxation rate in the rotating frame between the acquisitions can be computed. This parameter can be used to compute other parameters of magnetization transfer.

Artefact reduction in magnetic resonance imaging

Techniques of prospectively compensating for motion of a subject being imaged by an MRI system, the MRI system comprising a plurality of magnetics components including at least one gradient coil and at least one radio-frequency (RF) coil, the techniques comprising: obtaining first spatial frequency data and second spatial frequency data by operating the MRI system in accordance with a pulse sequence, wherein the pulse sequence is associated with a sampling path that includes at least two non-contiguous portions each for sampling a central region of k-space; determining a transformation using a first image obtained using the first spatial frequency data and a second image obtained using the second spatial frequency data; correcting the pulse sequence using the determined transformation to obtain a corrected pulse sequence; and obtaining additional spatial frequency data in accordance with the corrected pulse sequence.

Systems and methods for magnetic resonance imaging

A method for magnetic resonance imaging (MRI) is provided. The method may include obtaining scan data of a subject. The scan data may be acquired by an MR scanner at a time according to a pulse sequence. The method may include obtaining motion data of the subject. The motion data of the subject may be acquired by one or more sensors at the time. The motion data may reflect a motion state of the subject at the time. The method may also include determining, based on the motion data of the subject, a processing strategy indicating whether using the scan data to fill one or more k-space lines corresponding to the pulse sequence in a k-space. The method may further include obtaining k-space data based on the processing strategy.

SYSTEM AND METHOD FOR CONTROLLING PHYSIOLOGICAL NOISE IN FUNCTIONAL MAGNETIC RESONANCE IMAGING
20230023393 · 2023-01-26 ·

A system and method is provided for controlling physiological-noise in functional magnetic resonance imaging using raw k-space data to extract physiological noise effects. The method can identify these effects when they are separable and directly reflects the artefactual effects on fMRI data, without the need for external monitoring or recording devices and to be compensated for via rigorous statistical analysis modeling of such noise sources. The physiological fluctuations may be treated as global perturbations presented around the origin point in a k-space 2D slice. Each k-space 2D slice may be acquired at a very short repetition time with an effective sampling rate to sample cardiac and respiratory rhythms through proper reordering and phase-unwarping techniques applied to the raw k-space data.

Method for attenuating the noise in images resulting from multiple acquisitions by magnetic resonance imaging

A system and method for denoising experimental data originating from multiple acquisitions by a magnetic resonance imaging device, by analysis of selected principal components, to obtain a better compromise between the efficiency of the denoising and retention of the relevant information in the experimental data under consideration during their reconstruction to produce denoised experimental data. A selection criterion is based on the informative indicators quantifying the spatial information contained in images of scores associated with said principal components. The invention also provides for the capability to apply an adaptive filtering excluding the persistent spatial noise associated with each component selected.

Medical image processing apparatus and method
11561273 · 2023-01-24 · ·

A medical image processing apparatus including processing circuitry configured to obtain MR dynamic images acquired by MR imaging on a subject, in which a contrast agent has been injected, in accordance with an examination-time imaging condition including magnetic field information, contrast agent information, and/or tissue information, set a standard imaging condition, and calculate a first index value indicating a temporal change of an MR signal value caused by the contrast agent, the index value being standardized by conversion from the examination-time imaging condition to the standard imaging condition based on the MR dynamic images, the examination-time imaging condition, and the standard imaging condition.

Magnetic resonance imaging apparatus with auto-positioning function, method for controlling magnetic resonance imaging apparatus, and program for auto-setting of imaging plane

An imaging unit of an MRI apparatus performs imaging of a positioning image of a subject including a spine; a first imaging that images a cross section including the spine and extending along a longitudinal direction of the spine; and a second imaging that images a cross section in a direction of traversing the spine. An automatic cross-section position setting unit detects a specific tissue of the spine using a scout image or an image including the spine acquired in the first imaging step, performs a matching process between the detected specific tissue of the spine and a spine model, and calculates an imaging cross-section position of the second imaging based upon a specific tissue position of the spine specified by matching, thereby performing automatic setting.

Magnetic resonance imaging apparatus, image processor, and image processing method

An automatic clipping technique capable of satisfactorily extracting blood vessels to be extracted is provided. A specific tissue extraction mask image which is created by extracting a specific tissue (for example, a brain) from a three-dimensional image acquired by magnetic resonance angiography and a blood vessel extraction mask image which is created by extracting a blood vessel from an area (a blood vessel search area) which is determined using a preset landmark position and the specific tissue extraction mask image are integrated to create an integrated mask. By applying the integrated mask to the three-dimensional image, a blood vessel is clipped from the three-dimensional image.

Methods and apparatus for detecting injury using multiple types of magnetic resonance imaging data

Methods and apparatus for evaluating an impact of injury to brain networks or regions are provided. The method comprises receiving MRI data of a brain of an individual, including a first volumetric dataset recorded using first imaging parameters and a second volumetric dataset recorded using second imaging parameters, combining, on a voxel-by-voxel basis, first MRI data based on the first volumetric dataset and second MRI data based on the second volumetric dataset to produce a volumetric injury map, performing a structural-functional analysis of one or more brain networks or regions by refining the volumetric injury map using a volumetric eloquence map that specifies eloquent brain tissue within the one or more brain networks or regions to determine an impact of injury within the one or more brain networks or regions, and displaying a visualization of the determined impact of injury within the one or more brain networks or regions.

Methods and systems for analyzing brain lesions with longitudinal 3D MRI data

Some methods of analyzing one or more brain lesions of a patient comprise, for each of the lesion(s), calculating one or more lesion characteristics from a first 3-dimensional (3D) representation of the lesion obtained from data taken at a first time and a second 3D representation of the lesion obtained from data taken at a second time that is after the first time. The characteristic(s) can include a change, form the first time to the second time, in the lesion's volume and/or surface area, the lesion's displacement from the first time to the second time, and/or the lesion's theoretical radius ratio at each of the first and second times. Some methods comprise characterizing whether the patient has multiple sclerosis and/or the progression of multiple sclerosis in the patient based at least in part on the calculation of the lesion characteristic(s) of each of the lesion(s).