System and method for low-field, multi-channel imaging

Patent metadata

Field	Value
Publication number	US-10830848-B2
Application number	US-201515125514-A
Country	US
Kind code	B2
Filing date	Mar 13, 2015
Priority date	Mar 14, 2014
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

A system and method for performing parallel magnetic resonance imaging (pMRI) process using a low-field magnetic resonance imaging (IfMRI) system includes a substrate configured to follow a contour of a portion of a subject to be imaged by the IfMRI system using a pMRI process. A plurality of coils are coupled to the substrate. Each coil in the plurality of coils has a number of turns and an associated decoupling mechanism selected to operate the plurality of coils to effectuate the pMRI process using the IfMRI system.

First claim

The invention claimed is:

1. A coil system for performing a parallel magnetic resonance imaging (pMRI) process using a low-field magnetic resonance imaging (lfMRI) system, the system comprising:
a substrate configured to follow a contour of a portion of a subject to be imaged by the lfMRI system using a pMRI process; and
a plurality of coils coupled to the substrate, each coil in the plurality of coils having a plurality of turns and an associated decoupling mechanism selected to operate the plurality of coils to effectuate the pMRI process using the lfMRI system.

2. The coil system of claim 1 wherein the plurality of turns and the associated decoupling mechanism are selected to operate with a magnetic field strength of 6.5 mT.

3. The coil system of claim 1 wherein the plurality of coils are passively decoupled.

4. The coil system of claim 3 wherein transmit coils are passively decoupled using crossed diodes arranged in series.

5. The coil system of claim 3 wherein receive coils are passively decoupled using crossed diodes arranged in parallel.

6. The coil system of claim 1 wherein the each of the coils in the plurality of coils is tuned to 276.0 kHz.

7. The coil system of claim 1 wherein the each of the coils in the plurality of coils is matched to at least −27 dB.

8. The coil system of claim 1 wherein the each of the coils in the plurality of coils is geometrically decoupled from their nearest neighbors by at least −30 dB.

9. The coil system of claim 8 wherein decoupling from next-nearest neighbors is at least −6 dB.

10. The MRI system of claim 1 wherein the each of the coils in the plurality of coils is matched to at least −27 dB.

11. The MRI system of claim 1 wherein the each of the coils in the plurality of coils is geometrically decoupled from their nearest neighbors by at least −30 dB.

12. The MRI system of claim 11 wherein decoupling from next-nearest neighbors is at least −6 dB.

13. The coil system of claim 1 wherein each coil in the plurality of coils having a plurality of turns is formed using multi-strand wires.

14. The coil system of claim 13 wherein the multi-stand wires form a Litz wire.

15. A magnetic resonance imaging (MRI) system, comprising:
a magnet system configured to generate a low-field static magnetic field about at least a region of interest (ROI) of a subject arranged in the MRI system;
a plurality of gradient coils configured to establish at least one magnetic gradient field with respect to the low-field static magnetic field;
a radio frequency (RF) system including a local coil comprising:
a substrate configured to follow a contour of a portion of the subject including the ROI; and
a plurality of coils coupled to the substrate, each coil in the plurality of coils having a plurality of turns and an associated decoupling mechanism selected to operate the plurality of coils to effectuate a parallel imaging process using the low-field static magnetic field.

16. The MRI system of claim 15 wherein magnetic field strength is 6.5 mT.

17. The MRI system of claim 15 wherein the plurality of turns and the associated decoupling mechanism is selected to operate with the low-field static magnetic field.

18. The MRI system of claim 15 wherein the plurality of coils are passively decoupled.

19. The MRI system of claim 18 wherein transmit coils are passively decoupled using crossed diodes arranged in series.

20. The MRI system of claim 18 wherein receive coils are passively decoupled using crossed diodes arranged in parallel.

21. The MRI system of claim 15 wherein the each of the coils in the plurality of coils is tuned to 276.0 kHz.

22. The MRI system of claim 15 wherein the coils in the plurality of coils are arranged in a tiling geometry to be aligned about the ROI and either longitudinally or transversely to low-field static magnetic field.

23. The MRI system of claim 15 wherein each coil in the plurality of coils having a plurality of turns is formed using multi-strand wires.

24. The MRI system of claim 23 wherein the multi-stand wires form a Litz wire.

Assignees

• Massachusetts Gen Hospital

Inventors

• Rosen Matthew S
• Wald Lawrence L
• Lapierre Cristen

Classifications

• 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

• G01R33/3657 Primary

  Decoupling of multiple RF coils wherein the multiple RF coils do not have the same function in MR, e.g. decoupling of a transmission coil from a receive coil · CPC title

• G01R33/34046 Primary

  Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils · CPC title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• G01R33/365

  Decoupling of multiple RF coils wherein the multiple RF coils have the same function in MR, e.g. decoupling of a receive coil from another receive coil in a receive coil array, decoupling of a transmission coil from another transmission coil in a transmission coil array · CPC title