Open MRI magnet

• US 5,153,546 A
• Filed: 06/03/1991
• Issued: 10/06/1992
• Est. Priority Date: 06/03/1991
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Laskaris, Evangelos T.
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): Barrera, Ramon M.
• Application Number:
  US07/709,528
• Time in Patent Office: 491 Days
• Field of Search: 335/209-214, 335/216, 335/219, 335/296, 335/297, 335/298, 335/299, 335/300, 335/301, 335/304, 315/5.35, 324/318, 324/319, 324/320, 324/321, 128/653 SC, 128/653 R, 128/653 CA, 128/653 A, 128/, 505/892, 505/893
• US Class Current: 335/216
• CPC Class Codes: G01R 33/28 Details of apparatus provided for in groups G01R33/44 - G01R33/64
• CPC Class Codes: G01R 33/3806 Open magnet assemblies for improved access to the sample, e.g. C-type or U-type magnets

Abstract

In an open MRI magnet, the magnet is capable of being rotated such that a patient can be imaged while either lying down or standing up. The open MRI magnet is rotated about a pivot located upon a pedestal.

Claims

1. An open MRI magnet which is comprised of:

a support means being a pivot connection means;

a pair of superconductive coil assemblies substantially located at a distance from each other to provide a gap between said assemblies, said coil assemblies are further comprised of at least two superconductor coils, a support ring means rigidly attached to and spanning said coils, a shell means rigidly attached to said support ring means, and a thermal shield means; and

a coil assembly support means rigidly attached to said coil assemblies and having a pivot means such that said pivot means contacts and rotates in said pivot connection means.

2. The open MRI magnet, according to claim 1, wherein said support means is further comprised of:

a pedestal means.

3. The open MRI magnet, according to claim 1, wherein said coil assembly support means is further comprised of:

a C-shaped structural member means rigidly attached to said shell means; and

an envelope means.

4. The open MRI magnet, according to claim 1, wherein said pivot means is further comprised of:

a bearing means;

an envelope means contacting and rotating on said bearing means;

a heat conduction means rigidly attached at one end to said thermal shield means and rigidly attached at the other end to a cryocooler; and

a vibration adsorption means.

5. The open MRI magnet, according to claim 3, wherein said pivot means is further comprised of:

a bearing means;

said envelope means contacting and rotating on said bearing means;

a heat conduction means rigidly attached at one end to said structural member means and rigidly attached at the other end to a cryocooler; and

a vibration absorption means.

6. The open MRI magnet, according to claim 1, wherein said magnet can be rotated such that a patient can be imaged while either lying down or standing up.

7. The open MRI magnet, according to claim 4, wherein said heat conduction means is further comprised of:

at least one tube means.

8. The open MRI magnet, according to claim 5, wherein said heat conduction means is further comprised of:

at least one tube means.

9. The open MRI magnet, according to claim 1, wherein said magnet operates over a range of about 0.3 to 0.5 Tesla with a 30 cm volume having approximately a 30 ppm inhomogeneity or better.

10. The open MRI magnet, according to claim 4, wherein said magnet receives heat from the environment while said magnet is operating such that said heat is conducted along said coils to said ring means to said shell means to said shield means to said heat conduction means and dissipates said heat to a cryocooler.

11. The open MRI magnet, according to claim 5, wherein said magnet receives heat from the environment while said magnet is operating such that said heat is conducted along said coils to said heat is conducted along said coils to said structural member means to said heat conduction means and dissipate said heat to a cryocooler.