CATHETER ELECTRODE THAT CAN SIMULTANEOUSLY EMIT ELECTRICAL ENERGY AND FACILITATE VISUALIZATION BY MAGNETIC RESONANCE IMAGING

• US 20090171187A1
• Filed: 12/26/2007
• Published: 07/02/2009
• Est. Priority Date: 12/26/2007
• Status: Active Grant

• Current Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Original Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Inventors: Dando, Jeremy D., Puryear, Harry, Petersen, Scott R., Gerhart, John P.
• Granted Patent: US 8,175,679 B2
• Time in Patent Office: Days
• US Class Current: 600/421
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/283 Invasive

Abstract

An electrode for use on a medical device is disclosed. The electrode may have a main body of electrically conductive material extending along an axis and having a proximal end and a distal end. The body may be configured to emit electrical energy in accordance with a predefined diagnostic or therapeutic function. The body may have a groove disposed over an outermost surface of the body. The electrode may also include a magnetic resonance imaging (MRI) tracking coil disposed in said groove. The MRI tracking coil may comprise electrically insulated wire, for example. A catheter including an electrode, as well as a method for determining the location of an electrode, are also disclosed.

Claims

1. An electrode for use on a medical device comprising:

a main body of electrically conductive material extending along an axis and having a proximal end and a distal end, said body being configured to emit electrical energy in accordance with a predefined diagnostic or therapeutic function;

said body having a groove disposed over an outermost surface of said body;

a magnetic resonance imaging (MRI) tracking coil disposed in said groove, said MRI tracking coil comprising electrically insulated wire.

2. The electrode of claim 1, wherein said predefined function is a radio frequency (RF) ablation function.

3. The electrode of claim 1, wherein said groove comprises a continuous spiral niche.

4. The electrode of claim 3, wherein said niche has a width substantially corresponding to a diameter of said wire.

5. The electrode of claim 1, wherein said groove comprises a single channel extending radially inwardly from said outmost surface, said channel having a width large enough to house said MRI tracking coil.

6. The electrode of claim 1, wherein said groove comprises first and second channels extending radially inwardly from said outermost surface, said first channel being axially offset from said second channel by a predetermined distance.

7. The electrode of claim 5, wherein said first and second channels have a width along said axis that is substantially larger than a depth in the radial direction.

8. The electrode of claim 5, wherein said predetermined distance is about 0.5 mm.

9. The electrode of claim 5, wherein said MRI tracking coil has a first segment with a first predetermined number of turns and a second segment with a second predetermined number of turns.

10. The electrode of claim 6, wherein said first segment is disposed in said first channel and said second segment is disposed in said second channel, said first and second segments being electrically series-connected.

11. The electrode of claim 9, wherein said first and second predetermined number of turns is about five.

12. The electrode of claim 1, wherein said body is solid.

13. The electrode of claim 1, wherein said body comprises a non-ferrous material.

14. The electrode of claim 1, wherein said body comprises a gold alloy.

15. The electrode of claim 1, wherein said wire is electrically conductive.

16. The electrode of claim 1, wherein said groove has an entry and an exit and extends a predetermined number of turns from said entry to said exit.

17. The electrode of claim 16, wherein said predetermined number of turns is at least 10 turns.

18. The electrode of claim 1, wherein said groove has a width equal to or less than about 0.5 mm.

19. The electrode of claim 1, wherein said groove has a depth sufficient to receive said MRI tracking coil so that said MRI tracking coil is not disposed externally to said outermost surface of said body of said electrode.

20. The electrode of claim 1, further comprising an electrically conductive polymer disposed in said groove so that an outermost surface of said polymer is substantially flush with said outermost surface of said body of said electrode.

21. The electrode of claim 20, wherein said polymer comprises silicone with gold particles dispersed therein at a predefined density to achieve a desired electrical conductivity.

22. The electrode of claim 1, further comprising an electrical conductor having a first end coupled to said body and a second end configured for connection to an energy source.

23. The electrode of claim 22, wherein said energy source comprises a radio frequency ablation generator.

24. The electrode of claim 1, wherein said MRI tracking coil is configured for developing an induced signal having sufficient information encoded therewith to be indicative of a position of said electrode and to enable a magnetic resonance imaging (MRI) system to depict a location of said electrode in a patient.

25. The electrode of claim 1, wherein said body includes a plurality of slits.

26. A catheter, comprising:

a shaft; and

an electrode disposed on said shaft, said electrode comprising;

a main body of electrically conductive material extending along an axis and having a proximal end and a distal end;

said body having a groove disposed over an outermost surface of said body;

a magnetic resonance imaging (MRI) tracking coil disposed in said groove, said MRI tracking coil comprising electrically insulated wire; and

an MI receiving coil configured for MRI imaging disposed in said shaft proximate said electrode.

27. The catheter of claim 26, said MRI receiving coil comprising electrically conductive wire.

28. The catheter of claim 26, wherein said MRI receiving coil comprises a superconducting material.

29. The catheter of claim 26, further including a means for tuning or detuning said MRI receiving coil.

30. The catheter of claim 26, further including a second MRI tracking coil disposed in said shaft.

31. The catheter of claim 26, further comprising a micro-coaxial cable configured for connection to said MRI tracking coil, said cable extending through said shaft.

32. A method of determining the location of an electrode, comprising:

providing an electrode having a main body of electrically conductive material extending along an axis and having a proximal end and a distal end;

forming a groove in an outermost surface of said body; and

disposing a magnetic resonance imaging (MRI) tracking coil in said groove, said MRI tracking coil comprising electrically insulated wire.

33. The method of claim 32, further comprising receiving an induced signal developed in said MRI tracking coil at a magnetic resonance imaging (MRI) system input.

34. The method of claim 32, further comprising transmitting a magnetic field in order to facilitate tracking of said electrode within a magnetic resonance imaging (system.