G01R33/5602

METHOD AND APPARATUS FOR RECONSTRUCTING AN ELECTRICAL CONDUCTIVITY MAP FROM MAGNETIC RESONANCE IMAGING
20230168328 · 2023-06-01 ·

The exemplary embodiments provides an apparatus and a method for reconstructing an electrical conductivity map which reconstruct an electrical conductivity map for high resolution clinical data with a low SNR by generating virtual magnetic resonance imaging data and ground-truth electrical conductivity map data based on simulated data and adding a noise to the virtual magnetic resonance imaging data to train a previously designed deep learning network.

SYSTEMS AND METHODS FOR DESIGNING MULTIDIMENSIONAL SELECTIVE ADIABATIC PULSES
20170307708 · 2017-10-26 ·

Described here are systems and methods for designing and implementing spatially selective, multidimensional adiabatic radio frequency (“RF”) pulses for use in magnetic resonance imaging (“MRI”). Spatially selective inversion can be achieved adiabatically in both two-dimensional (“2D”) and three-dimensional (“3D”) regions-of-interest. The multidimensional adiabatic pulses are generally designed using sub-pulses that are adiabatically driven using a parent adiabatic pulse.

Integration of T2-preparation and motion tracking in magnetic resonance imaging

An embodiment in accordance with the present invention provides concurrent measurement of motion during T2-weighted magnetic resonance imaging. The present invention combines T2 preparation, a module used to impart T2 contrast, and motion measurement, tracking, and/or correction. The present invention provides for the expedition of more efficient motion compensation during T2-weighted imaging. The proposed invention can be used to provide a variety of measurements of motion, with no overhead in imaging time. The proposed invention also enables T2 contrast imaging to be executed while a subject is breathing freely, without the additional time cost associated with the standard motion tracking methodologies.

Image domain segmented echo planar magnetic resonance imaging using a 2D excitation radiofrequency pulse

Representative methods and systems are disclosed for reducing image distortion or increasing spatial resolution in echo planar magnetic resonance imaging. In representative embodiments, a targeted field of view (FOV) image is divided into segments, with each segment having a predetermined overlap region with an adjacent segment, such as in a phase-encoding direction. Image data is acquired for each segment, sequentially or simultaneously, using a reduced phase-encoding FOV with a 2D radiofrequency (RF) excitation pulse, and rotated and scaled magnetic field gradients. The 2D RF excitation pulse may also be modulated, such as onto a plurality of different carrier frequencies, for simultaneous acquisition of multiple segments in the same imaging plane. Using the spatial response of the 2D RF excitation pulse, the acquired image data for each segment of the plurality of segments is combined to generate a combined magnetic resonance image having the targeted field of view.

METHOD OF REMOVING GHOST ARTIFACTS FROM MAGNETIC RESONANCE IMAGE, AND MAGNETIC RESONANCE APPARATUS THEREFOR

A method of reconstructing a magnetic resonance image includes receiving echo planar imaging (EPI) data, acquiring an even scan line image and an odd scan line image from k-space data of the EPI data, and reconstructing missing portions of the even scan line image and the odd scan line image.

Magnetic resonance imaging apparatus

A magnetic resonance imaging apparatus according to an embodiment includes an execution unit and a generation unit. The execution unit executes first data collection after a predetermined inversion time elapses from a time when a labeling pulse is applied to a fluid flowing into an imaging region of a subject and a second data collection without application of the labeling pulse. The generation unit generates a differential image by using the first data and the second data. Here, the generation unit generates the differential image by a different differential method according to a relationship between the inversion time and a longitudinal relaxation time of the fluid.

SYSTEM AND METHOD FOR DELTA RELAXATION ENHANCED MAGNETIC RESONANCE IMAGING

A delta-relaxation magnetic resonance imaging (DREMR) system is provided. The system includes a main field magnet and field shifting coils. A main magnetic field with a strength B0 can be generated using the main filed magnet and the strength B0 of the main magnetic field can be varied through the use of the field-shifting coils. The DREMR system can be used to perform signal acquisition based on a pulse sequence for acquiring at least one of T2*-weighted signals imaging; MR spectroscopy signals; saturation imaging signals and MR signals for fingerprinting. The MR signal acquisition can be augmented by varying the strength B0 of the main magnetic field for at least a portion of the pulse sequence used to acquire the MR signal.

Magnetic resonance imaging apparatus

Provided is an MRI apparatus. In the MRI apparatus, a data collection unit repetitively performs a tag mode of applying an RF wave to at least an upstream portion of an imaging area to perform fluid labeling of a fluid flown into the imaging area and, after a lapse of an inversion time from application of the RF wave, performing magnetic resonance data collection, while changing the inversion time. An image reconstruction unit reconstructs a plurality of tag images corresponding to a plurality of different inversion times based on the magnetic resonance data collected in the tag mode. A reference image generation unit generates a reference image based on the plurality of the tag images. A fluid image generation unit generates a subtraction image between each of the tag images and the reference image as a fluid image.

TENSOR FIELD MAPPING

During operation, a system may apply an external magnetic field and an RF pulse sequence to a sample. Then, the system may measure at least a component of a magnetization associated with the sample, such as MR signals of one or more types of nuclei in the sample. Moreover, the system may calculate at least a predicted component of the magnetization for voxels associated with the sample based on the measured component of the magnetization, a forward model, the external magnetic field and the RF pulse sequence. Next, the system may solve an inverse problem by iteratively modifying the parameters associated with the voxels in the forward model until a difference between the predicted component of the magnetization and the measured component of the magnetization is less than a predefined value. Note that the calculations may be performed concurrently with the measurements and may not involve performing a Fourier transform.

MRI-BASED FEEDBACK CONTROL OF ULTRASOUND BASED MECHANICAL FRACTIONATION OF BIOLOGICAL TISSUE
20220304588 · 2022-09-29 ·

Disclosed herein are example embodiments of devices, systems, and methods for mechanical fractionation of biological tissue using magnetic resonance imaging (MRI) feedback control. The examples may involve displaying an image representing first MRI data corresponding to biological tissue, and receiving input identifying one or more target regions of the biological tissue to be mechanically fractionated via exposure to first ultrasound waves. The examples may further involve applying the first ultrasound waves and, contemporaneous to or after applying the first ultrasound waves, acquiring second MRI data corresponding to the biological tissue. The examples may also involve determining, based on the second MRI data, one or more second parameters for applying second ultrasound waves to the biological tissue, and applying the second ultrasound waves to the biological tissue according to the one or more second parameters.