MR field probes with additional windings for improving the homogeneity and localizing the measuring volume

Patent metadata

Field	Value
Publication number	US-10168399-B2
Application number	US-201614997071-A
Country	US
Kind code	B2
Filing date	Jan 15, 2016
Priority date	Jan 22, 2015
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

The embodiments relate to a method and field probes for measuring a static and/or in particular a dynamic magnetic field in an imaging magnetic resonance tomography system, wherein the field probe includes a body surrounded by a coil. The coil includes a middle or center winding section and at least one or two outer winding sections.

First claim

The invention claimed is:

1. A field probe for measuring a magnetic field in an imaging magnetic resonance tomography system, the field probe comprising:
a body; and
a coil surrounding at least a portion of the body, the coil having a center winding section and two outer winding sections, each outer winding section being adjacent to the center winding section,
wherein the two outer winding sections continue the center winding section such that a gap between the two outer winding sections has a negligible influence on a basic field of a magnetic resonance tomography device.

2. The field probe of claim 1 , wherein the center winding section and the two outer winding sections each have a same diameter.

3. A field probe for measuring a magnetic field in an imaging magnetic resonance tomography system, the field probe comprising:
a body; and
a coil surrounding at least a portion of the body, the coil having a center winding section and two outer winding sections, each outer winding section being adjacent to the center winding section,
wherein the two outer winding sections are provided with a HF short circuit by way of a capacitor for and/or during a measurement of time-varying fields.

4. The field probe of claim 3 , wherein the center winding section is isolated from the two outer winding sections.

5. The field probe of claim 1 , wherein the two outer winding sections are each elongated, wherein each outer winding section has a length of at least two times of a diameter of the respective outer winding section.

6. A field probe for measuring a magnetic field in an imaging magnetic resonance tomography system, the field probe comprising:
a body; and
a coil surrounding at least a portion of the body, the coil having a center winding section and an outer winding section,
wherein the center winding section and the outer winding section have separate coil connections.

7. The field probe of claim 1 , wherein the body is filled with a liquid, which is surrounded by the coil by which a nuclear resonance is configured to be excited, read out, or excited and read out in the liquid.

8. The field probe of claim 7 , wherein the liquid is water or benzene.

9. The field probe of claim 1 , wherein only the center winding section is provided or connected for signal generation purposes.

10. The field probe of claim 1 , wherein the center winding section of the coil is connected to or is configured to be connected to a spectrometer.

11. The field probe of claim 1 , wherein the center winding section of the coil is configured to be switched or connected to a resonance capacitor.

12. The field probe of claim 6 , wherein the outer winding section is configured to be short-circuited for the measurement of a radio-frequency field.

13. The field probe of claim 1 , wherein at least 80% of a length of a tube in the field probe is configured to be filled with a liquid such that ends of a liquid column of the liquid and sealing plugs are distanced from a measured volume of the liquid.

14. The field probe of claim 1 , wherein the field probe comprises a tube having an elongated liquid column.

15. The field probe of claim 14 , wherein the elongated liquid column has a length of more than five times a diameter of the tube.

16. The field probe of claim 1 , wherein the center winding section has a length of less than two times a diameter of the center winding section.

17. The field probe of claim 1 , wherein the center winding section and the two outer winding sections each has a diameter, and
a gap of less than 20% of the respective diameters exists between the center winding section and each outer winding section of the two outer winding sections.

18. The field probe of claim 1 , wherein a nuclear resonance is configured to be excited, read out, or excited and read out with the coil.

19. The field probe of claim 1 , wherein the coil comprises an electrical conductor having a conductor material made of copper.

20. The field probe of claim 1 , wherein the body, the coil, or the body and the coil are each cylindrical.

21. The field probe of claim 1 , wherein the center winding section and the two outer winding sections surround the same axis.

22. The field probe of claim 1 , wherein the body is filled with a liquid, which, in a longitudinal direction, is delimited by two plugs made of a non-signal-generating material.

23. The field probe of claim 1 , wherein the center winding section does not overlap with each outer winding section of the two outer winding sections.

24. The field probe of claim 1 , wherein the coil is a radio-frequency coil.

25. A method for measuring a field in a magnetic resonance tomography system, the method comprising:
providing a field probe having a body and a coil surrounding at least a portion of the body, the coil having a center winding section and at least one outer winding section; and
generating a signal by a short active area in the center winding section, which is connected to a resonance capacitor and a spectrometer;
continuing the signal in the at least one outer winding section;
short-circuiting the at least one outer winding section such that a field is considered to have been pushed out from the at least one outer winding section; and
measuring the field.

26. A magnetic resonance tomography system comprising:
at least one field probe comprising:
a body; and
a coil surrounding at least a portion of the body, the coil having a center winding section and two outer winding sections, each outer winding section being adjacent to the center winding section,
wherein the center winding section is isolated from the two outer winding sections.

Assignees

• Rehner Robert
• Vester Markus
• Siemens Ag

Inventors

• Rehner Robert
• Vester Markus

Classifications

• G01R33/56563

  caused by a distortion of the main magnetic field B0, e.g. temporal variation of the magnitude or spatial inhomogeneity of B0 (G01R33/56509, G01R33/56518, G01R33/56536 take precedence) · CPC title

• G01R33/422

  of the radio frequency field · CPC title

• G01R33/58

  Calibration of imaging systems, e.g. using test probes {, Phantoms; Calibration objects or fiducial markers such as active or passive RF coils surrounding an MR active material} · CPC title

• G01R33/34053

  Solenoid coils; Toroidal coils · CPC title

• G01R33/24 Primary

  for measuring direction or magnitude of magnetic fields or magnetic flux · CPC title