Methods for adjusting a magnetic field of a magnetic resonance tomography device, magnetic power supplies, and magnetic resonance tomography devices

Patent metadata

Field	Value
Publication number	US-10698051-B2
Application number	US-201816149248-A
Country	US
Kind code	B2
Filing date	Oct 2, 2018
Priority date	Oct 6, 2017
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A method for adjusting a magnetic field of a magnetic resonance tomography (MRT)-device having a magnet includes: transferring the magnet from an operating state to a non-operating state in a ramp-down mode; subsequently transferring the magnet from the non-operating state to the operating state in a ramp-up mode; observing a reference parameter different from the magnetic field; setting a target value for the reference parameter; comparing the observed reference parameter to the target value; and finishing the ramp-up mode when the reference parameter reaches the target value.

First claim

The invention claimed is:

1. A method for adjusting a magnetic field of a magnetic resonance tomography (MRT)-device having a magnet, the method comprising:
transferring the magnet from an operating state to a non-operating state in a ramp-down mode;
subsequently transferring the magnet from the non-operating state to the operating state in a ramp-up mode;
observing a reference parameter different from the magnetic field, wherein the reference parameter comprises a current;
setting a target value for the reference parameter, wherein the current is calibrated during a previous ramp-up mode, a previous ramp-down mode, or a combination thereof;
comparing the observed reference parameter to the target value; and
finishing the ramp-up mode when the reference parameter reaches the target value.

2. The method of claim 1 , wherein the current is for realizing the magnetic field of the magnet.

3. The method of claim 1 , wherein, in the setting of the target value, the current is calibrated during the previous ramp-up mode.

4. The method of claim 3 , wherein the previous ramp-up mode is a preceding ramp-up mode.

5. The method of claim 1 , wherein, in the setting of the target value, the current is calibrated during the previous ramp-down mode.

6. The method of claim 5 , wherein the previous ramp-down mode is a preceding ramp-down mode.

7. The method of claim 5 , wherein, in the setting of the target value, the current is observed during an initiation phase of the ramp-down mode.

8. The method of claim 1 , wherein the current is measured by a current measuring device included into a magnetic power supply of the MRT-device.

9. The method of claim 5 , wherein the ramp-down mode is an emergency ramp-down mode.

10. The method of claim 1 , wherein the reference parameter further comprises a frequency.

11. The method of claim 10 , wherein the frequency is a frequency emitted by a phantom being placed into the MRT-device.

12. The method of claim 11 , wherein the phantom is placed into the MRT-device before the ramp-up mode starts or during the ramp-up mode.

13. The method of claim 11 , wherein the phantom is automatically placed into the MRT-device before the ramp-up mode starts or during the ramp-up mode.

14. The method of claim 1 , wherein the target value is reset after a predefined period of time.

15. The method of claim 1 , wherein the target value is automatically reset after a predefined period of time.

16. The method of claim 1 , wherein the ramp-down mode is initiated by a control unit by a failure message of the MRT-device, after a defined time sequence, as a result of a activation, or a combination thereof.

17. The method of claim 1 , wherein a magnetic field in the operating state is less than 1.5 T.

18. A magnetic power supply configured to:
transfer a magnet from an operating state to a non-operating state in a ramp down mode;
subsequently transfer the magnet from the non-operating state to the operating state in a ramp-up mode;
observe a reference parameter, wherein the reference parameter comprises a current;
set a target value for the reference parameter, wherein the current is calibrated during a previous ramp-up mode, a previous ramp-down mode, or a combination thereof;
compare the observed reference parameter to the target value; and
finish the ramp-up mode when the reference parameter reaches a target value.

19. The magnetic power supply of claim 18 ,
wherein the magnetic power supply comprises a current measuring device configured to observe the current.

20. A magnetic resonance tomography (MRT)-device configured to:
transfer the magnet from an operating state to a non-operating state in a ramp-down mode;
subsequently transfer the magnet from the non-operating state to the operating state in a ramp-up mode;
observe a reference parameter, wherein the reference parameter comprises a current;
set a target value for the reference parameter, wherein the current is calibrated during a previous ramp-up mode, a previous ramp-down mode, or a combination thereof;
compare the observed reference parameter to the target value; and

finish the ramp-up mode when the reference parameter reaches a target value.

Assignees

• Siemens Healthcare Gmbh

Inventors

• Aley Nicholas
• Biber Stephan

Classifications

• G01R33/3815 Primary

  with superconducting coils, e.g. power supply therefor · CPC title

• H01F6/006

  Supplying energising or de-energising current; Flux pumps · CPC title

• G01R33/381

  using electromagnets · CPC title

• G01R33/389

  Field stabilisation {, e.g. by field measurements and control means or indirectly by current stabilisation} · CPC title

• G01R33/421 Primary

  of main or gradient magnetic field · CPC title