Microcoil device with a forward field-of-view for large gain magnetic resonance imaging

• US 6,587,706 B1
• Filed: 03/21/2000
• Issued: 07/01/2003
• Est. Priority Date: 08/22/1997
• Status: Expired due to Fees

• Current Assignee: Image-Guided Drug Delivery Systems, Inc.
• Original Assignee: Image-Guided Drug Delivery Systems, Inc.
• Inventors: Viswanathan, Raju R.
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): Lin, Jeoyuh
• Application Number:
  US09/532,037
• Time in Patent Office: 1,197 Days
• Field of Search: 600/407, 600/409, 600/410, 600/411, 600/419, 600/423, 600/425, 600/427, 600/9, 600/10, 600/11-13, 604/19, 604/21, 607/101, 607/104, 324/300, 324/301, 324/313, 324/318, 324/322, 324/219
• US Class Current: 600/410
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• 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 5/4839 combined with drug delivery
• CPC Class Codes: A61M 25/0105 Steering means as part of the catheter or advancing means; Markers for positioning systems for detection of markers A61B
• CPC Class Codes: A61M 25/0108 using radio-opaque or ultrasound markers
• CPC Class Codes: A61M 25/0127 Magnetic means; Magnetic markers

Abstract

Microcoils can be used in medical devices to enhance RF response signals and to create fields to enhance imaging capability in MRI imaging systems. An improved microcoil design includes a device to be inserted into a patient comprising a solid body having at least one pair of radially opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, individual windings of each microcoil together defining a geometric plane for each microcoil, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of radially opposed microcoils.

Claims

1. A device adapted to be inserted into a patient, the device comprising a solid body having at least one pair of radially opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, individual windings of said each microcoil together defining a geometric plane for each microcoil, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of radially opposed microcoils.

2. The device according to claim 1 wherein in the presence of a continuous electrical path, at least one pair of radially opposed microcoils form a spiral pair wherein one microcoil of every spiral pair is wound radially inward and the other microcoil of that pair is wound radially outward about the coil axis, with all microcoils of the spiral pair having the same sense of winding about a common axis of the spiral pair.

3. The device of claim 1 wherein said geometric plane is a plane defined by averaging individual microcoil positions, and at least 80% by volume of all windings within said microcoil lie within 2 mm of the geometric plane.

4. The device of claim 3 wherein said device comprises a catheter having at least one lumen, and said at least one pair of radially opposed microcoils.

5. The device of claim 3 wherein at least one drug delivery port is present within said device.

6. The device of claim 3 wherein said at least one microcoil is embedded within a binder material.

7. The device of claim 3 wherein said at least one pair of microcoils is electrically connected to a preamplifier attached to a portion of said device that may be inserted into an organism.

8. The device of claim 7 wherein said at least one microcoil is embedded within a binder material.

9. The device of claim 1 wherein the sense of the windings and a source of current for said windings are electromagnetically related so that a magnetic field generated by passing current through at least one pair of radially opposed microcoils will extend in a direction that is more distal from a geometric center of said solid body than said pair of radially opposed microcoils.

10. The device of claim 9 wherein said device comprises a catheter having at least one lumen and said at least one pair of radially opposed microcoils.

11. The device of claim 9 wherein at least one drug delivery port is present within said device.

12. The device of claim 9 wherein said at least one pair of microcoils is electrically connected to a preamplifier attached to a portion of said device that may be inserted into an organism.

13. The device of claim 12 wherein said at least one microcoil is embedded within a binder material.

14. The device of claim 1 wherein there are from 2 to 6 pairs of radially opposed microcoils physically associated with said device.

15. The device of claim 14 wherein said device comprises a catheter having at least one lumen, and said at least one pair of radially opposed microcoils.

16. The device of claim 14 wherein at least one drug delivery port is present within said device.

17. The device of claim 14 wherein said at least one pair of microcoils is electrically connected to a preamplifier attached to a portion of said device that may be inserted into an organism.

18. The device of claim 1 wherein said device comprises a catheter having at least one lumen and said at least one pair of radially opposed microcoils.

19. The device of claim 1 wherein at least one drug delivery port is present within said device.

20. The device of claim 1 wherein said at least one microcoil is embedded within a binder material.

21. The device of claim 1 wherein said at least one pair of microcoils is electrically connected to a preamplifier attached to a portion of said device that may be inserted into an organism.

22. The device of claim 1 wherein said geometric plane is a plane defined by mathematically averaging individual winding positions, and at least 80% of all windings within said microcoil lie within 2 mm of the geometric plane.

23. The device of claim 1 wherein the sense of the windings and a source of current for said windings are electromagnetically related so that a magnetic field generated by passing current through said at least one pair of opposed microcoils will extend in a direction that is more distal from a geometric center of said solid body than said pair of opposed microcoils.

24. The device of claim 1 wherein there are from 2 to 6 pairs of opposed microcoils physically associated with said device.

25. A method of generating an electromagnetic RF receptive field exterior to a device comprising:

providing a device comprising a solid body having a geometric center and a distal end, with at least one pair of radially opposed microcoils physically associated with the solid body at said distal end, each microcoil having an outside microcoil diameter of 6 mm or less, the individual windings of said each microcoil defining a geometric plane, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of radially opposed microcoils;

providing a radio frequency field around said device; and

generating an RF responsive spatial region extending from said at least one pair of opposed microcoils toward or beyond said distal end.

26. A device adapted to be inserted into a patient, the device comprising a solid body having at least one pair of opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, collective individual windings of said each microcoil defining a geometric plane, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of opposed microcoils.

27. The device of claim 26 wherein said device comprises a catheter having at least one lumen, and said at least one pair of opposed microcoils.

28. The device of claim 26 wherein at least one drug delivery port is present within said device.

29. The device of claim 26 wherein said at least one microcoil is embedded within a binder material.

30. The device of claim 26 wherein said at least one pair of microcoils is electrically connected to a preamplifier attached to a portion of said device that may be inserted into an organism.

31. A device adapted to be inserted into a patient, the device comprising a solid body having at least one pair of opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, at least 50 number % of individual windings of said each microcoil lying within a geometric plane, and the geometric plane of each microcoil being parallel to the plane of another microcoil in the pair of opposed microcoils, and there being at least four windings within each microcoil in said at least one pair of opposed microcoils.

32. A method of generating an electromagnetic RF responsive field exterior to an device comprising:

providing a device comprising a solid body having a geometric center and a distal end, with at least one pair of opposed microcoils physically associated with the solid body at said distal end, each microcoil having an outside microcoil diameter of 6 mm or less, the geometrically averaged position of individual windings of said each microcoil defining a geometric plane, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of opposed microcoils;

providing a changing magnetic field around said at least one pair of opposed microcoils to generate an electrical signal in said microcoils; and

a responsive field from said microcoils extending from said at least one pair of opposed microcoils towards or beyond said distal end.

33. A method of generating an electromagnetic RF responsive field exterior to an device comprising:

providing a device comprising a solid body having a geometric center and a distal end, with at least one pair of opposed microcoils physically associated with the solid body at said distal end, each microcoil having an outside microcoil diameter of 6 mm or less, at least 50 number % of individual windings of said each microcoil lying within a geometric plane;

causing a change in a magnetic field around said device to generate a field response from said microcoils; and

a responsive field extending from said at least one pair of opposed microcoils towards or beyond said distal end.

34. A device adapted to be inserted into a patient the device comprising a solid body having at least one pair of radially opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, with at least one pair of opposed microcoils physically associated with the solid body at a distal end, at least 50 number % of individual windings of said each microcoil lying within a geometric plane.

35. A device adapted to be inserted into a patient, the device comprising a solid body having at least one pair of radially opposed microcoils physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, all individual windings of said each microcoil lying within a geometric plane, and the plane of each microcoil being parallel to the plane of another microcoil in the pair of radially opposed microcoils.

36. A device adapted to be inserted into a patient, the device comprising a solid body having at least one microcoil physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, the individual windings of said each microcoil lying within a geometric plane.

37. The device of claim 36 wherein said geometric plane is a plane defined by averaging individual microcoil positions, and at least 80% of all windings within said microcoil planes are parallel to said geometric plane within 2 mm of the geometric plane.

38. The device of claim 36 wherein the sense of the windings and a source of current for said windings are electromagnetically related so that a magnetic field generated by passing current said at least one microcoil will extend in a direction that is more distal from a geometric center of said solid body than said microcoil.

39. The device of claim 36 wherein there are from 1 to 13 microcoils physically associated with said device.

40. The device of claim 36 wherein said device comprises a catheter having at least one lumen, and said at least one microcoil.

41. The device of claim 36 wherein at least one drug delivery port is present within said device.

42. The device of claim 36 wherein said at least one microcoil is embedded within a binder material.

43. The device of claim 36 wherein said at least one microcoil is electrically connected to a preamplifier within a portion of said device which may be inserted into an organism.

44. A device adapted to be inserted into a patient, the device comprising a solid body having at least one microcoil physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less, at least 50 number % of individual windings of said each microcoil lying within a geometric plane perpendicular to an axis of said microcoil.

45. A method of generating an electromagnetic RF receptive field exterior to a device comprising:

providing a device comprising a solid body having a geometric center and a distal end, with at least one microcoil physically associated with the solid body at said distal end, each microcoil having an outside microcoil diameter of 6 mm or less, the individual windings of said each microcoil defining a geometric plane;

providing a radio frequency field around said device; and

a receptive field extending from said at least one microcoil beyond said distal end.

46. A method of generating an electromagnetic RF receptive field exterior to a device comprising:

providing a device comprising a solid body having a geometric center and a distal end, with at least one microcoil physically associated with the solid body at said distal end, each microcoil having an outside microcoil diameter of 6 mm or less, at least 50% of individual windings of said each microcoil lying within a geometric plane;

providing a radio frequency field around said device; and

a receptive field extending from said at least one microcoil beyond said distal end.

47. A device adapted to be inserted into a patient, the device comprising a solid body having at least one microcoil physically associated with the solid body, each microcoil having an outside microcoil diameter of 6 mm or less and a common axis, with at least one microcoil physically associated with the solid body at a distal end, at least 50% of individual windings of said each microcoil lying within a geometric plane perpendicular to said common axis.