APPARATUS AND SYSTEM FOR INTERVENTIONAL MAGNETIC RESONANCE IMAGING

• US 20060267585A1
• Filed: 05/31/2005
• Published: 11/30/2006
• Est. Priority Date: 05/31/2005
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Havens, Timothy John
• Granted Patent: US 7,274,192 B2
• Time in Patent Office: Days
• US Class Current: 324/318
• CPC Class Codes: G01R 33/3806 Open magnet assemblies for improved access to the sample, e.g. C-type or U-type magnets

Abstract

A magnetic resonance imaging (MRI) magnet having a first section and a second section is disclosed. The first section has a first housing, and a first set of magnet coils arranged about a common axis that include coils proximate the common axis. The second section has a second housing, and a second set of magnet coils arranged about the common axis where the coils are radially displaced from the common axis. The second section is connected to but axially displaced a distance “d” from the first section.

Claims

1. A magnetic resonance imaging (MRI) magnet, comprising:

a first section having a first housing and a first set of magnet coils arranged about a common axis, the first set of magnet coils including coils proximate the common axis; and

a second section having a second housing and a second set of magnet coils arranged about the common axis, the second set of magnet coils being radially displaced from the common axis;

wherein the second section is connected to but axially displaced a distance “

d”

from the first section.

2. The magnet of claim 1, wherein:

in response to an energized magnet, a field of view is established within the distance “

d”

.

3. The magnet of claim 1, wherein:

in response to an energized magnet, a field of view is established on the common axis.

4. The magnet of claim 1, wherein:

the second section is connected to the first section via a set of supports that provide openings to allow side access to an object disposed between the first and second sections.

5. The magnet of claim 1, wherein:

the second section is ring-shaped thereby providing an axial opening to allow end access to an object disposed between the first and second sections.

6. The magnet of claim 1, wherein:

the first section is a closed magnet; and

the second section is an open magnet.

7. The magnet of claim 1, wherein:

the first set of magnet coils comprises a primary coil, a compensation coil, a shielding coil, or any combination comprising at least one of the foregoing coils; and

the second set of magnet coils comprises a primary coil, a compensation coil, a shielding coil, or any combination comprising at least one of the foregoing coils.

8. The magnet of claim 1, wherein:

the first section comprises iron sufficient to effect stray field management.

9. The magnet of claim 1, wherein:

the first section, the second section, or both first and second sections comprises iron sufficient to effect magnetic field homogeneity at a field of view.

10. The magnet of claim 1, wherein:

the distance “

d”

is sufficient to receive a human head.

11. The magnet of claim 1, wherein:

the distance “

d”

is equal to or greater than about 30 centimeters.

12. The magnet of claim 1, wherein;

the distance “

d”

is equal to or greater than about 40 centimeters.

13. The magnet of claim 5, wherein:

the axial opening of the second section has a diameter sufficient to receive a human arm.

14. The magnet of claim 5, wherein:

the axial opening of the second section has a diameter equal to or greater than about 30 centimeters.

15. The magnet of claim 1, wherein:

the cross section of the second section reduces in size with an increasing distance from the first section.

16. The magnet of claim 5, wherein:

the inner diameter of the second section increases with an increasing distance from the first section.

17. A magnetic resonance imaging (MRI) magnet, comprising:

a closed magnet having a first housing and a first set of magnet coils arranged about a common axis, the first set of magnet coils including coils proximate the common axis;

an open ring-shaped magnet having a second housing and a second set of magnet coils arranged about the common axis, the second set of magnet coils being radially displaced from the common axis thereby providing an axial opening to allow end access to an object disposed between the closed and open magnets; and

the open magnet being connected to but axially displaced a distance “

d”

from the closed magnet via a set of supports that provide openings to allow side access to the object disposed between the closed and open magnets.

18. A magnetic resonance imaging (MRI) system, comprising:

a MRI magnet; and

a control system for controlling the operation of the MRI magnet such that MRI data of an object may be generated and saved for subsequent post-processing and analysis;

wherein the MRI magnet comprises;

a first section having a first housing and a first set of magnet coils arranged about a common axis, the first set of magnet coils including coils proximate the common axis;

a second section having a second housing with an axial opening therethrough and a second set of magnet coils arranged about the common axis, the second set of magnet coils being radially displaced from the common axis;

the second section being connected to but axially displaced a distance “

d”

from the first section via a set of supports with side openings therebetween; and

wherein side access through the side openings and end access through the axial opening is allowed to an object disposed between the two sections.

19. An open MRI magnet assembly comprising:

a closed ended magnet; and

an open ended magnet connected to the closed ended magnet and having a volume defined therebetween, the open ended magnet having an opening therethrough to allow access to the volume defined between the open ended magnet and the closed ended magnet.

20. The open MRI magnet assembly of claim 19 further comprising a plurality of supports connecting the closed ended magnet and the open ended magnet.

21. The open MRI magnet assembly of claim 20 wherein each of the plurality of supports has a height such that a passage is formed between the open ended magnet and the closed ended magnet to allow a subject to be removably positioned in the volume between the open ended magnet and the closed ended magnet.

22. The open MRI magnet assembly of claim 21 wherein the plurality of supports is arranged circumferentially around the closed ended magnet such that a number of side access openings is formed generally orthogonal to the opening of the open ended magnet.

23. The open MRI magnet assembly of claim 19 wherein the opening in the open ended magnet is sized to allow access of an interventional apparatus to a subject disposed in the volume between the open ended magnet and the closed ended magnet.

24. The open MRI magnet assembly of claim 19 wherein the open ended magnet is ring-shaped.

25. The open MRI magnet assembly of claim 19 wherein the closed ended magnet comprises iron sufficient to effect stray field management.

26. The open MRI magnet assembly of claim 19 further comprising a first housing having the closed ended magnet therein and a second housing having the open ended magnet therein, and further comprising an operation control interface supported by one of the first housing and the second housing.

27. The open MRI magnet assembly of claim 19 configured to generate at least a 1.5 T magnetic field in the volume defined between the open ended magnet and the closed ended magnet.

28. The open MRI magnet assembly of claim 19 wherein each magnet includes at least one of a primary coil, a compensation coil, and a shielding coil.