Medical device with an electrically conductive anti-antenna member

• US 20050288752A1
• Filed: 08/30/2005
• Published: 12/29/2005
• Est. Priority Date: 08/25/2003
• Status: Abandoned Application

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Biophan Technologies Incorporated
• Inventors: Gray, Robert W.
• Application Number:
  US11/214,624
• Publication Number:
  US 20050288752A1
• Time in Patent Office: Days
• US Class Current: 607/115
• CPC Class Codes: A61B 2090/0481 against EM radiation, e.g. microwave
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 90/04 Protection of tissue around surgical sites against effects of non-mechanical surgery, e.g. laser surgery protection of eyes against laser radiation A61F9/022
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2210/009 magnetic
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/124 of other specific inorganic materials not covered by A61L31/122 or A61L31/123
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: A61N 1/00 Electrotherapy; Circuits therefor A61N2/00 takes precedence; irradiation apparatus A61N5/00
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/37 Monitoring; Protecting
• CPC Class Codes: A61N 2/00 Magnetotherapy
• CPC Class Codes: G01R 33/285 Invasive instruments, e.g. catheters or biopsy needles, specially adapted for tracking, guiding or visualization by NMR

Abstract

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal'"'"'s frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

Claims

1. A medical device, comprising:

a housing having electronic components therein;

a lead operatively connected to said electronic components within said housing; and

a resonant circuit, located within said housing, operatively connected to said lead and said electronic components;

said resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a magnetic-resonance imaging scanner.

2. The medical device as claimed in claim 1, wherein said resonant circuit is an inductor connected in parallel with a capacitor.

3. The medical device as claimed in claim 1, wherein said resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

4. The medical device as claimed in claim 1, wherein said resonant circuit has a resonance frequency of about 64 MHz.

5. The medical device as claimed in claim 1, further comprising:

a second resonant circuit, located within said housing, operatively connected to said resonant circuit;

said second resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a second magnetic-resonance imaging scanner.

6. The medical device as claimed in claim 5, wherein said second resonant circuit is an inductor connected in parallel with a capacitor.

7. The medical device as claimed in claim 5, wherein said second resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

8. The medical device as claimed in claim 5, wherein said second resonant circuit has a resonance frequency of about 128 MHz.

9. A medical device, comprising:

a housing having electronic components therein;

a multi-conductor lead circuit operatively connected to said housing; and

a resonant circuit, located within said housing, operatively connected to a conductor of said multi-conductor lead circuit and said electronic components;

said resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a magnetic-resonance imaging scanner.

10. The medical device as claimed in claim 9, wherein said resonant circuit is an inductor connected in parallel with a capacitor.

11. The medical device as claimed in claim 9, wherein said resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

12. The medical device as claimed in claim 9, wherein said resonant circuit has a resonance frequency of about 64 MHz.

13. The medical device as claimed in claim 9, further comprising:

a second resonant circuit operatively connected to said resonant circuit;

said second resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a second magnetic-resonance imaging scanner.

14. The medical device as claimed in claim 13, wherein said second resonant circuit is an inductor connected in parallel with a capacitor.

15. The medical device as claimed in claim 13, wherein said second resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

16. The medical device as claimed in claim 13, wherein said second resonant circuit has a resonance frequency of about 128 MHz.

17. The medical device as claimed in claim 9, further comprising:

a heat receiving mass;

said heat receiving mass being located adjacent to said resonant circuit and dissipating the heat generated by said resonant circuit.

18. The medical device as claimed in claim 9, further comprising:

a heat dissipating structure;

said heat dissipating structure being located adjacent to said resonant circuit and dissipating the heat generated by said resonant circuit.

19. The medical device as claimed in claim 9, further comprising:

a third resonant circuit, located within said housing, operatively connected to a second conductor of said multi-conductor lead circuit and said electronic components;

said third resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a magnetic-resonance imaging scanner.

20. The medical device as claimed in claim 19, wherein said third resonant circuit is an inductor connected in parallel with a capacitor.

21. The medical device as claimed in claim 19, wherein said third resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

22. The medical device as claimed in claim 19, wherein said third resonant circuit has a resonance frequency of about 64 MHz.

23. The medical device as claimed in claim 19, further comprising:

a fourth, resonant circuit operatively connected to said third resonant circuit;

said fourth resonant circuit having a resonance frequency approximately equal to an excitation signal'"'"'s frequency of a second magnetic-resonance imaging scanner.

24. The medical device as claimed in claim 23, wherein said fourth resonant circuit is an inductor connected in parallel with a capacitor.

25. The medical device as claimed in claim 23, wherein said fourth resonant circuit is an inductor connected in parallel with a capacitor and a resistor, said resistor and capacitor being connected in series.

26. The medical device as claimed in claim 23, wherein said fourth resonant circuit has a resonance frequency of about 128 MHz.

27. The medical device as claimed in claim 9, wherein the multi-conductor lead circuit is a bipolar pacing lead.

28. The medical device as claimed in claim 9, wherein the multi-conductor lead circuit is a deep brain stimulator lead.

29. The medical device as claimed in claim 9, wherein the multi-conductor lead circuit is a four conductor deep brain stimulator lead.