Leland Stanford Junior University

University of California

Ge Precision Healthcare LLC

Peder E Larson

John Mark Pauly

Adam Bruce Kerr

Daniel Blackburn Vigneron

Steven M Conolly

Florian Wiesinger

Ana Beatriz Solana Sanchez

Albert P Chen

Brice Fernandez

Andrew Leynes

A magnetic resonance (MR) dynamically imaging method is provided. The method includes acquiring a functional MR dataset including frames of k-space datasets, while a functional stimulus is applied to the subject. Acquiring the functional MR dataset includes, acquiring a frame of k-space datasets by setting an orientation as an initial angle, and acquiring a free induction decay (FID) dataset. Acquiring an FID dataset includes applying a sequence of gradients, each gradient of the sequence corresponding to a k-space spoke, wherein the sequence of k-space spokes define a k-space segment having the orientation in a 3D k-space volume. Acquiring a frame of k-space datasets also includes acquiring a gradient echo dataset corresponding to the FID dataset, and updating the orientation as golden angles. The method also includes generating anatomical MR images and functional images based on the functional MR dataset.

Systems and methods of silent multi-gradient echo dynamic magnetic resonance imaging

A method for imaging a substrate and product over time is provided. The substrate and product are magnetically tagged with at least one magnetic gradient where magnetically tagging provides a tag-dependent signal phase for the substrate and a different tag-dependent signal phase for the product. At least one readout of magnetically tagged substrate and product is provided over time. The tag-dependent signal phase is used to determine product that has been transformed from magnetically tagged substrate and substrate that has been transformed from magnetically tagged product over time.

Phase-sensitive imaging of magnetization exchange and isotope flux

A method for performing magnetic resonance spectroscopy is described. The method generally includes applying a tailored multiband spectral-spatial radio frequency excitation pulse to a sample including a first species and at least a second species having a different resonant frequency than the first species. The multiband excitation pulse excites the first species according to a first amplitude and excites the second species according to a second amplitude that is substantially greater than the first amplitude. Data is acquired from the sample. The acquired data is then utilized to generate a spectroscopic output. By way of example, the spectroscopic output is a spectroscopic image. In particular embodiments, the data for the first and second species is acquired dynamically over an observation window of time.

Hyperpolarized dynamic chemical shift imaging with tailored multiband excitation pulses

In imaging a first species having a short T2 magnetic resonance parameter in the presence of a second and third species having longer T2 parameters, a method of suppressing signals from the longer T2 species comprises the steps of: a) applying a RF saturation pulse with multiple suppression bands for the second and third species to excite nuclei spins of the longer T2 species with the magnitude of the RF pulse being sufficiently low so as not to excite nuclei spins of the short T2 species, the RF saturation pulse being sufficiently long to rotate the longer T2 species nuclei spins into a transverse plane, and b) dephasing the longer T2 species nuclei spins in the transverse plane. An imaging pulse sequence is then applied to image the short T2 species. Alternatively, the method can comprise the steps of a) applying a first inversion pulse for selective inverting species of the second longer T2 species, b) obtaining first image signals after step a, c) applying a second inversion pulse for selectively inverting species of the third longer T2 species, d) obtaining second image signals after step c), and e) combining the first image signals and the second image signal to image the first short T2 species with the longer second and third species cancelling in the combination. In each of these methods, either the second or third longer T2 species can be suppressed without suppressing the other by applying the RF saturation or inversion pulse only to the species to be suppressed.

RF pulses for long T2 suppression in MRI

Growing community of inventors

Oakland, CA, United States of America

Peder E Larson