Systems and methods for fast magnetic resonance image reconstruction using a heirarchically semiseparable solver

Patent metadata

Field	Value
Publication number	US-10126397-B2
Application number	US-201514707598-A
Country	US
Kind code	B2
Filing date	May 8, 2015
Priority date	May 9, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

Systems and methods for reconstructing images using a hierarchically semiseparable (“HSS”) solver to compactly represent the inverse encoding matrix used in the reconstruction are provided. The reconstruction method includes solving for the actual inverse of the encoding matrix using a direct (i.e., non-iterative) HSS solver. This approach is contrary to conventional reconstruction methods that repetitively evaluate forward models (e.g., compressed sensing or parallel imaging forward models).

First claim

The invention claimed is:

1. A method for reconstructing an image of a subject from data acquired using a magnetic resonance imaging (MRI) system, the steps of the method comprising:
(a) providing data acquired from a subject using an MRI system;
(b) computing an inverse of an encoding matrix using a hierarchically semiseparable solver;
(c) reconstructing an image of the subject from the provided data using the computed inverse of the encoding matrix.

2. The method as recited in claim 1 , wherein step (b) includes computing the inverse of the encoding matrix by performing a structured factorization of the encoding matrix.

3. The method as recited in claim 2 , wherein the factorization can be represented using low-rank modeling.

4. The method as recited in claim 1 , wherein the encoding matrix is based on a Split Bregman reconstruction.

5. The method as recited in claim 4 , wherein the encoding matrix includes a penalty term based on a total variation sparsity.

6. The method as recited in claim 5 , wherein the penalty term relaxes an L 1 norm by solving for L 2 targets.

7. The method as recited in claim 6 , wherein the L 2 targets include vertical and horizontal finite difference targets.

8. The method as recited in claim 6 , wherein the targets are updated using a soft-thresholding technique.

9. The method as recited in claim 1 , wherein step (b) includes non-iteratively computing the inverse of the encoding matrix.

Assignees

• Cauley Stephen
• Bilgic Berkin
• Setsompop Kawin
• Wald Lawrence
• Massachusetts Gen Hospital

Inventors

• Cauley Stephen
• Bilgic Berkin
• Setsompop Kawin
• Wald Lawrence

Classifications

• G01R33/385

  using gradient magnetic field coils · CPC title

• G01R33/5611

  Parallel magnetic resonance imaging, e.g. sensitivity encoding [SENSE], simultaneous acquisition of spatial harmonics [SMASH], unaliasing by Fourier encoding of the overlaps using the temporal dimension [UNFOLD], k-t-broad-use linear acquisition speed-up technique [k-t-BLAST], k-t-SENSE (structural details of arrays of sub-coils G01R33/3415) · CPC title

• G01R33/5608 Primary

  Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels (image data processing or generation, in general G06T) · CPC title

• G01R33/5615

  Echo train techniques involving acquiring plural, differently encoded, echo signals after one RF excitation, e.g. using gradient refocusing in echo planar imaging [EPI], RF refocusing in rapid acquisition with relaxation enhancement [RARE] or using both RF and gradient refocusing in gradient and spin echo imaging [GRASE] · CPC title

• G01R33/5673

  Gating or triggering based on a physiological signal other than an MR signal, e.g. ECG gating or motion monitoring using optical systems for monitoring the motion of a fiducial marker · CPC title