Magnetic resonance apparatus and operating method therefor with monitoring and control of RF energy-relevant operating value

Patent metadata

Field	Value
Publication number	US-10928466-B2
Application number	US-201715591451-A
Country	US
Kind code	B2
Filing date	May 10, 2017
Priority date	May 10, 2016
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

In a magnetic resonance apparatus and a method for operation thereof, at least one electrical operating value of at least one predetermined component of the apparatus is captured and, as a function of the at least one operating value, at least one coil operating value of a transmitting coil arrangement of the magnetic resonance apparatus is controlled for the purpose of limiting a B1 value.

First claim

The invention claimed is:

1. A method for operating a magnetic resonance (MR) apparatus, said MR apparatus comprising an MR data acquisition scanner comprising a plurality of scanner components which include at least one coil that is operable to radiate radio-frequency (RF) energy, said method comprising:
determining the RF energy radiated by said coil by detecting at least one electrical operating value of at least a predetermined one of said scanner components using a capacitive coupler that interacts with said at least one predetermined scanner component;
providing an input signal, representing the detected at least one electrical operating value, to a processor and, in said processor, generating a coil control signal, dependent on said input signal, that limits RF energy radiated by said coil; and
from said processor, emitting said coil control signal in order to control at least one coil operating value of said coil, and thereby limit the RF energy radiated by said coil in accordance with said control signal.

2. A method as claimed in claim 1 comprising detecting, as said at least one electrical operating value, an operating value that is proportional to a current associated with operation of said coil.

3. A method as claimed in claim 1 comprising detecting a voltage value as said at least one electrical operating value.

4. A method as claimed in claim 3 wherein said plurality of scanner components include a receiving coil, that receives RF energy radiated by said coil, and detecting said at least one operating value as a voltage value of said receiving coil.

5. A method as claimed in claim 3 wherein said plurality of scanner components include a rectifying coupler, and detecting said at least one electrical operating value as a voltage value of said at least one rectifying coupler.

6. A method as claimed in claim 3 wherein said plurality of scanner components comprise an electrical connection, and detecting said at least one operating value as a voltage value at said at least one electrical connection.

7. A method a claimed in claim 1 comprising detecting a current value as said at least one electrical operating value.

8. A method as claimed in claim 7 wherein said plurality of scanner components comprise an electrical connection, and detecting said at least one operating value as a current value at said at least one electrical connection.

9. A method as claimed in claim 1 comprising, in said processor, generating said coil control signal so as to limit a maximum value of the coil operating value controlled by said coil control signal.

10. A method as claimed in claim 1 comprising, in said processor, generating said coil control signal so as to limit an average value of the coil operating value controlled by said coil control signal.

11. A method as claimed in claim 1 wherein said MR data acquisition scanner comprises, as one of said plurality of scanner components, a basic field magnet that produces a basic magnetic field in said MR data acquisition scanner of more than one 1.5 T, and wherein said method comprises, in said processor, generating said coil control signal with a safety factor that limits said coil operating value controlled by said coil control signal by more than a nominal value required to limit said RF energy.

12. A method as claimed in claim 1 comprising generating said coil control signal with a safety factor that limits said coil operating value controlled by said coil control signal by more than a nominal value required to limit said RF energy.

13. A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a computer of a magnetic resonance (MR) apparatus comprising an MR data acquisition scanner comprising a plurality of scanner components which include at least one coil that is operable to radiate radio-frequency (RF) energy, and said programming instructions causing said computer to:
operate a detector to detect at least one electrical operating value of at least a predetermined one of said scanner components to thereby determine, using a capacitive coupler that interacts with said at least one predetermined scanner component, the RF energy radiated by said coil;
receive an input signal, representing the detected at least one electrical operating value, and generate a coil control signal, dependent on said input signal, that limits RF energy radiated by said coil; and
emit said coil control signal in order to control at least one coil operating value of said coil, and thereby limit the RF energy radiated by said coil in accordance with said control signal.

14. A non-transitory, computer-readable data storage medium as claimed in claim 13 , wherein said programming instructions causes said computer to generate said coil control signal with a safety factor that limits said coil operating value controlled by said coil control signal by more than a nominal value required to limit said RF energy.

15. A magnetic resonance (MR) apparatus comprising:
an MR data acquisition scanner comprising a plurality of scanner components which include at least one coil that is operable to radiate radio-frequency (RF) energy;
a detector that detects at least one electrical operating value of at least a predetermined one of said scanner components to thereby determine, using a capacitive coupler that interacts with said at least one predetermined scanner component, the RF energy radiated by said coil;
a processor provided with an input signal, representing the detected at least one electrical operating value, to a processor, and said processor being configured to generate a coil control signal, dependent on said input signal, that limits RF energy radiated by said coil; and
said processor being configured to emit said coil control signal in order to control at least one coil operating value of said coil, and thereby limit the RF energy radiated by said coil in accordance with said control signal.

16. An MR apparatus as claimed in claim 15 wherein said processor is configured to generate said coil control signal with a safety factor that limits said coil operating value controlled by said coil control signal by more than a nominal value required to limit said RF energy.

Assignees

• Siemens Healthcare Gmbh

Inventors

• Bielmeier Wolfgang
• Brinker Gerhard
• Campagna Swen
• Erbe Bernd
• Gebhardt Matthias
• Nistler Juergen
• Paul Dominik
• Prinz Carsten
• Ruyters Gudrun
• Stoecker Stephan
• Vester Markus

Classifications

• G01R33/3607

  RF waveform generators, e.g. frequency generators, amplitude-, frequency- or phase modulators or shifters, pulse programmers, digital to analog converters for the RF signal, means for filtering or attenuating of the RF signal · CPC title

• G01R33/543

  Control of the operation of the MR system, e.g. setting of acquisition parameters prior to or during MR data acquisition, dynamic shimming, use of one or more scout images for scan plane prescription (G01R33/546 takes precedence) · CPC title

• G01R33/288 Primary

  Provisions within MR facilities for enhancing safety during MR, e.g. reduction of the specific absorption rate [SAR], detection of ferromagnetic objects in the scanner room · CPC title