General Electric Company

Wisconsin Alumni Research Foundation

Reed Frederick Busse

Philip James Beatty

James Hartman Holmes

Jean Helen Brittain

Ersin Bayram

Frank R Korosec

Kang Wang

John Mark Pauly

Kevin Franklin King

Scott Brian Reeder

Kevin Matthew Koch

Xiaoli Zhao

Ajeetkumar Gaddipati

Anthony Tienhuan Vu

Greg Zaharchuk

Manojkumar Saranathan

Charles Robert Michelich

Zhiqiang Li

Howard Andrew Rowley

Raman Krishnan Subramanian

Dan W Rettmann

A method includes the acts of acquiring a blade of k-space calibration data; acquiring a set of T1-weighted k-space imaging data, the set of T1-weighted k-space imaging data having blades of undersampled k-space data rotated about a section of k-space. Each blade of undersampled k-space data includes first data points having acquired data and second data points that are missing data. The method also includes generating a set of reconstruction weights for the blades of undersampled k-space data using the blade of k-space calibration data; synthesizing k-space data for at least a portion of the second data points using the set of reconstruction weights; and generating a T1-weighted image using the T1-weighted k-space imaging data and the synthesized k-space data.

Motion correction in accelerated T1-weighted magnetic resonance imaging

The present disclosure is intended to describe embodiments for improving image data acquisition and processing in accelerated dynamic magnetic resonance imaging sequences. One embodiment is described where a method includes an acquisition sequence configured to acquire an undersampled set of magnetic resonance data. The undersampled set of magnetic resonance data has a pseudo-random sampling pattern within a data space acquired at a first time, the pseudo-random sampling pattern being influenced by other pseudo-random sampling patterns within the data space arising from the acquisition of additional undersampled sets of magnetic resonance data at respective times. In some embodiments, the pseudo-random sampling patterns of the undersampled sets of magnetic resonance data interleave to yield a desired sampling pattern.

Accelerated pseudo-random data magnetic resonance imaging system and method

A system and method for enhanced contrast MR imaging include a computer programmed to perform a first scan of an imaging object based on a first fast spin echo (FSE) scan sequence comprising a first series of RF pulses having a first flip angle sequence to acquire a first MR data set and perform a second scan of the imaging object based on a second FSE scan sequence comprising a second series of RF pulses having a second flip angle sequence, wherein the second flip angle sequence is different from the first flip angle sequence to acquire a second MR data set. The computer is further programmed to generate a difference image based on the first and second MR data sets.

System and method for enhanced contrast MR imaging

A method for calculating a flip angle schedule for a train of refocusing radio frequency (RF) pulses with reduced flip angles allows control of RF power deposition and use of a longer echo train. A target signal is defined for each echo in the echo train, and flip angles are then calculated from the target signals. The target signal schedule includes two phases. In the first phase, the target signals drop asymptotically to efficiently establish a pseudo-steady state at a pre-defined minimum signal level, S. In the second phase, the target signal is increased monotonically for the remainder of the train to a pre-defined maximum signal level, S. By increasing the target signal, the effect of relaxation may be reduced, decreasing blurring and ringing artifacts. Flip angles are then calculated from the target signal schedule, using a simplified method that requires no information about the tissues' relaxation properties.

Method and apparatus for generating a flip angle schedule for a spin echo train pulse sequence

A method of magnetic resonance (MR) imaging includes segmenting a k-kplane comprising a plurality of encoding points into a plurality of annular segments. For each annular segment, a view ordering is defined based on a polar angle associated with each encoding point contained within the annular segment. MR data is acquired for the plurality of encoding points based on the view ordering for each annular segment and at least one MR image is generated using the acquired MR data.

System and method of angular elliptic centric view ordering for 3D MR acquisitions

A method for acquiring magnetic resonance (MR) data for a pulse sequence with periodic signal modulation and a set of views having at least two phase encode directions includes selecting a direction of modulation. Each view in the set of views is assigned a readout number based on a position of each view along the direction of modulation resulting in a plurality of readout number groups, each readout number group having a plurality of views. Each view within each readout number group is assigned a train number based on a position of each view along a second direction in k-space. MR data for the set of views is acquired based on the assigned readout number and train number for each view.

Method and apparatus for acquiring MRI data for pulse sequences with multiple phase encode directions and periodic signal modulation

An apparatus and method for MR imaging in inhomogeneous magnetic fields includes acquisition of a plurality of three-dimensional (3D) MR data sets, each data set having a central transmit frequency and a central receive frequency set to a frequency offset that is distinct for each 3D MR data set. A composite image is generated based on the plurality of 3D MR data sets.

System and method for MR imaging in inhomogeneous magnetic fields

A preparatory pulse sequence is applied prior to an imaging pulse sequence during a diffusion-weighted MRI scan. The preparatory pulse sequence diffusion weights the longitudinal magnetization using a gradient waveform that is first moment nulled to reduce image artifacts caused by patient motion.

Diffusion weighted preparatory sequence for magnetic resonance imaging pulse sequence

A multi-shot three-dimensional (3D) magnetic resonance imaging (MRI) data view-ordering strategy for uniform or variable density k-space sampling schemes is presented. The k-kplane is partitioned into multiple wedge-shaped 'blades' (or radial fan beams). The angular size of individual blades may be adjusted according to the desired number of views for each blade. Each blade includes views near the origin that contain low-frequency information about the imaged object such that views having the most desirable characteristics may be used to fill the central portions of k-space.

Method and apparatus for acquiring magnetic resonance imaging data

Methods and systems for generating T1-weighted images are provided. The method includes acquiring a pair of single-shot fast-spin-echo (SSFSE) images Sand S. The method further includes generating a T1-weighted image Sbased on Sand S.

Method for generating T1-weighted magnetic resonance images and quantitative T1 maps

A technique is set forth that is designed to reduce RF induced power in high field MR imaging that includes application of an initial contrast preserving phase of RF pulses. These initial RF pulses are designed to have a constant, relatively high flip angle over the initial contrast preserving phase. Following an effective TE, a ramp down phase is applied that has a limited number of RF pulses with a flip angle that is less than the flip angle of those in the initial contrast preserving phase. Further, the RF pulses in the ramp down phase have a flip angle that is decreased over the ramp down phase. This technique provides improved resolution and steady contrast and SNR, while significantly reducing induced RF power.

Growing community of inventors

Madison, WI, United States of America

Reed Frederick Busse