General Electric Company

Mayo Foundation for Medical Education and Research

Ge Medical Systems Global Technology Company, LLC

Other

General Electric Corporation Gmbh

Matthew A Bernstein

Joshua D Trzasko

Yunhong Shu

Jason Andrew Polzin

Xiaohong Zhou

Joseph K Maier

Shengzhen Tao

Thomas K Foo

Yiping Du

Gousheng Tan

Xiaohang Zhou

Norbert Joseph Pelc

Kevin Franklin King

Gary H Glover

Alexander Ganin

Tsur Bernstein

John Huston, Iii

Hammond G Reynolds

Uten Yarach

Richard L Ehman

Armando Manduca

Thomas K F Foo

Richard Scott Hinks

Vincent B Ho

Erika Schneider

Frederick Joseph Frigo

Gregory A Repinski

Philip A Araoz

Yi Sui

Arvin Forghanian-Arani

Paul T Weavers

Yping Du

Myung-Ho In

Bo J Petersson

Steven M Metcalfe

Images are reconstructed from k-space data using a model-based image reconstruction that prospectively and simultaneously accounts for multiple non-idealities in accelerated single-shot-EPI acquisitions. In some implementations, nonlinear regularization (e.g., sparsity regularization) is also incorporated to mitigate noise amplification. The reconstructed images have reduced distortions and noise amplification effects relative to those images that are processed using conventional post-reconstruction techniques to correct for non-idealities.

Model-based iterative reconstruction for magnetic resonance imaging with echo planar readout

Nyquist ghost artifacts in echo planar imaging ('EPI') are mitigated, reduced, or otherwise eliminated by implementing robust Nyquist ghost correction (“NGC”) directly from two reversed readout EPI acquisitions. As one advantage, these techniques do not require explicit reference scanning. A model-based process is used for directly estimating statistically optimal NGC coefficients from multi-channel k-space data.

Model-based Nyquist ghost correction for reverse readout echo planar imaging

Described here are systems and methods for correcting motion-encoding gradient nonlinearities in magnetic resonance elastography ('MRE'). In general, the systems and methods described in the present disclosure compute gradient nonlinearity corrected displacement data based on information about the motion-encoding gradients used when acquiring magnetic resonance data.

Methods for correcting motion-encoding gradient nonlinearities in magnetic resonance elastography

Systems and methods for performing concomitant field corrections in magnetic resonance imaging ('MRI') systems that implement asymmetric magnetic field gradients are provided, in general, the systems and methods described here can correct for the effects of concomitant fields of multiple orders, such as zeroth order, first order, and second order concomitant fields.

Systems and methods for concomitant field correction in magnetic resonance imaging with asymmetric gradients

An asymmetric 3D shells k-space trajectory design with partial Fourier acceleration is described. A non-iterative homodyne reconstruction framework is also described.

Partial Fourier acquisition and reconstruction for k-space shells based magnetic resonance imaging

A system and method for simultaneously reconstructing magnetic resonance images and correcting those imaged for gradient nonlinearity effects are provided. As opposed to conventional methods for gradient nonlinearity correction where distortion is corrected after image reconstruction is performed, the model-based method described here prospectively accounts for the effects of gradient nonlinearity during reconstruction. It is a discovery of the inventors that the method described here can reduce the blurring effect and resolution loss caused by conventional correction algorithms while achieving the same level of geometric correction.

Integrated image reconstruction and gradient non-linearity correction for magnetic resonance imaging

A system and method for simultaneously reconstructing magnetic resonance images and correcting those imaged for gradient nonlinearity effects are provided. As opposed to conventional methods for gradient nonlinearity correction where distortion is corrected after image reconstruction is performed, the model-based method described here prospectively accounts for the effects of gradient nonlinearity during reconstruction and implements a spatial support constraint to reduce noise amplification effects.

Integrated image reconstruction and gradient non-linearity correction with spatial support constraints for magnetic resonance imaging

Systems and methods for efficiently generating MR images are provided. The method comprises acquiring k-space MR data, reconstructing an MR image from the k-space MR data, and generating the MR image. The MR image is reconstructed using an alternative-direction-method-of-multiplier (ADMM) strategy that decomposes an optimization problem into subproblems, and at least one of the subproblems is further decomposed into small problems. The further decomposition is based on Woodbury matrix identity and uses a diagonal preconditioner based on non-Toeplitz models.

Systems and methods for efficiently generating magnetic resonance images from incomplete data

A method for prescribing a scan on an MRI system includes selecting a general pulse sequence to be used during a time-resolved imaging process of a subject using an MRI system. The method also includes setting a first set of scan parameters to more specifically prescribe the general pulse sequence and setting a second set of scan parameters using a formula that relates time resolution and spatial resolution resulting from the first set of scan parameters. The method then includes performing the time-resolved imaging process using the general pulse sequence, the first set of scan parameters, and the second set of scan parameters.

Accelerated shells trajectory MRI acquisition

An MRI k-space data set is acquired using a series of shell k-space sampling trajectories of different radii. Off-resonance effects are reduced and fat-suppression can be improved by using a shorter TR for pulse sequences that sample at smaller radii. At larger radii sampling is repeated with the central axis of the shell sampling trajectory tilted such that the polar regions of shells acquired at the same radii are sampled by the other shell.

A 3D MRI image is acquired as a series of spherical shells of increasing radius. Each shell is sampled by one or more interleaved spiral sampling trajectories and to shorten the scan time one or more spiral sampling trajectories are skipped in the larger shells that sample the periphery of k-space. Motion correction of the acquired k-space data is accomplished by reconstructing tracking images from each of the shells and locating markers therein which indicate object movement from a reference position. The k-space data is corrected using this movement information.

Under-sampled 3D MRI using a shells k-space sampling trajectory

A CE-MIRA image is acquired using a centric view order. The acquired k-space data set is motion corrected by reconstructing tracking images from successive annular segments of k-space data and detecting the location of a point spread object therein. Each k-space data segment is phase corrected to align the point spread object with a reference position.

Motion correction of magnetic resonance images

An MRI system performs a pulse sequence to acquire image data from a subject. The RF power applied to the subject is monitored and the acquisition is altered if any one of three trip levels is exceeded. Each trip level is different and is associated with a different time interval over which applied RF power is measured.

MRI RF power monitor

An MRI system acquires NMR signals and digitizes them at a fixed sample rate. A lower, prescribed sample rate is obtained by fractionally decimating the sampled NMR signals. Fractional decimation is achieved by a combination of zeropadding the sampled NMR signal in the frequency domain and decimating the sampled NMR signal in the time domain.

MRI system with fractional decimation of acquired data

An MRI system acquires MRA data from two overlapping thin slabs using a 3DTOF pulse sequence. Motion artifacts are reduced by using a reverse centric phase encode order during the first thin slab acquisition and a centric phase encode order during the second thin slab acquisition. Patient movement is reduced by producing a uniform sound with gradient pulse sequences during the interval between thin slab acquisitions and during a preparation period prior to the first thin slab acquisition.

Growing community of inventors

Waukesha, WI, United States of America

Matthew A Bernstein