Ferromagnetic frame for magnetic resonance imaging

Patent metadata

Field	Value
Publication number	US-12553968-B2
Application number	US-202418649879-A
Country	US
Kind code	B2
Filing date	Apr 29, 2024
Priority date	Dec 10, 2019
Publication date	Feb 17, 2026
Grant date	Feb 17, 2026

Abstract

An apparatus for providing a B0 magnetic field for a magnetic resonance imaging system. The apparatus includes at least one permanent B0 magnet to contribute a magnetic field to the B0 magnetic field for the MRI system and a ferromagnetic frame configured to capture and direct at least some of the magnetic field generated by the B0 magnet. The ferromagnetic frame includes a first post having a first end and a second end, a first multi-pronged member coupled to the first end, and a second multi-pronged member coupled to the second end, wherein the first and second multi-pronged members support the at least one permanent B0 magnet.

First claim

What is claimed is:

1 . An apparatus for providing a B 0 magnetic field for a magnetic resonance imaging (MRI) system, the apparatus comprising:
at least one permanent B 0 magnet to contribute a magnetic field to the B 0 magnetic field for the MRI system, the at least one permanent B 0 magnet having an imaging region face and a non-imaging region face; a plurality of blades positioned proximate to the non-imaging region face of the at least one permanent B 0 magnet; and a ferromagnetic frame to capture and direct at least a portion of the magnetic field generated by the at least one permanent B 0 magnet.

2 . The apparatus of claim 1 , wherein the plurality of blades are arranged in a radial pattern about a center of the at least one permanent B 0 magnet.

3 . The apparatus of claim 1 , wherein the plurality of blades are arranged in a parallel pattern relative to a center of the at least one permanent B 0 magnet.

4 . The apparatus of claim 1 , wherein the plurality of blades are arranged in an orthogonal pattern relative to a center of the at least one permanent B 0 magnet.

5 . The apparatus of claim 1 , wherein the ferromagnetic frame further comprises:
a first post having a first end and a second end; and a first multi-pronged member coupled to the first end.

6 . The apparatus of claim 5 , wherein the first multi-pronged member comprises a stem and two prongs coupled to the stem.

7 . The apparatus of claim 6 , wherein the ferromagnetic frame further comprises:
a second multi-pronged member coupled to the second end, wherein the first and second multi-pronged members support the at least one permanent B 0 magnet.

8 . The apparatus as described in claim 1 , wherein the plurality of blades are composed of a same material as the ferromagnetic frame.

9 . The apparatus as described in claim 1 , wherein the plurality of blades are composed of a material different from the ferromagnetic frame.

10 . The apparatus of claim 1 , wherein the plurality of blades comprises a first plurality of ferromagnetic blades and a second plurality of ferromagnetic blades, wherein:
an end of each of the first plurality of ferromagnetic blades is coupled to a first multi-pronged member; and an end of each of the second plurality of ferromagnetic blades is coupled to a second multi-pronged member.

11 . The apparatus of claim 10 , wherein the ferromagnetic blades of the first and second pluralities of ferromagnetic blades are arranged to extend radially from a common center.

12 . The apparatus of claim 1 , wherein each of the plurality of blades is arranged to extend along a direction substantially parallel to one of an x- or y-gradient magnetic field.

13 . The apparatus of claim 1 , wherein each of the plurality of blades is conductive.

14 . The apparatus of claim 1 , wherein the plurality of blades includes a first pair of blades separated by a gap that is at least 110 mm and no greater than 140 mm.

15 . The apparatus of claim 14 , wherein the plurality of blades further includes a second pair of blades separated by the gap.

16 . The apparatus of claim 1 , wherein each of the plurality of blades comprises a tapered profile.

17 . The apparatus of claim 1 , wherein the plurality of blades comprises a blade that is tapered along its length.

18 . The apparatus of claim 1 , wherein the plurality of blades comprises 8 to 32 blades.

19 . The apparatus of claim 1 , wherein the plurality of blades comprises 2 to 8 blades.

20 . A magnetic resonance imaging (MRI) system comprising the apparatus of claim 1 .

Assignees

• Hyperfine Operations Inc

Inventors

• Hugon Cedric
• Dyvorne Hadrien A
• Poole Michael Stephen

Classifications

• G01R33/445

  MR involving a non-standard magnetic field B0, e.g. of low magnitude as in the earth's magnetic field or in nanoTesla spectroscopy, comprising a polarizing magnetic field for pre-polarisation, B0 with a temporal variation of its magnitude or direction such as field cycling of B0 or rotation of the direction of B0, or spatially inhomogeneous B0 like in fringe-field MR or in stray-field imaging · CPC title

• G01R33/3873

  using ferromagnetic bodies {; Passive shimming} · CPC title

• G01R33/385

  using gradient magnetic field coils · CPC title

• G01R33/34092

  RF coils specially adapted for NMR spectrometers · CPC title

• A61B5/055

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