Implantable pump with infinitely variable resistor

• US 20060259015A1
• Filed: 05/10/2005
• Published: 11/16/2006
• Est. Priority Date: 05/10/2005
• Status: Active Grant

• Current Assignee: Aqulinx Medical, Inc.
• Original Assignee: Palyon Medical Corporation
• Inventors: Steinbach, Bernd
• Granted Patent: US 8,114,055 B2
• Time in Patent Office: Days
• US Class Current: 604/891.100
• CPC Class Codes: A61M 5/141 with capillaries for restricting fluid flow
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/14586 pressurised by means of a flexible diaphragm
• CPC Class Codes: A61M 5/16813 by controlling the degree of opening of the flow line

Abstract

A variable hydraulic resistor for use with implantable pumps is disclosed. The variable hydraulic resistor according to the present invention is particularly useful in varying the flow rate of a medication fluid from an otherwise constant flow implantable pump. An implantable pump is also disclosed, which does not require a complicated clinching system or the like, and which may include an undulating membrane and chamber design to reduce the height of the pump.

Claims

1. An implantable device for dispensing an active substance to a patient comprising:

a housing defining a chamber, said housing having an outlet for delivering said active substance to a target site within said patient, said outlet in fluid communication with the chamber; and

means for varying a flow rate of said active substance between said chamber and said outlet.

2. The implantable device according to claim 1, wherein the chamber includes an active substance chamber in fluid communication with said outlet and a propellant chamber, the active substance and propellant chambers being separated by a flexible membrane.

3. The implantable device according to claim 2, wherein the propellant chamber contains a propellant capable of expanding isobarically, the propellant cooperating with the flexible membrane to reduce the volume of the active substance chamber upon expansion of the propellant.

4. The implantable device according to claim 2, further comprising an opening in said housing in fluid communication with the active substance chamber, and a first septum sealing the opening.

5. The implantable device according to claim 4, further comprising an annular opening in said housing communicating with said outlet, and a second septum sealing the annular opening.

6. The implantable device according to claim 1, wherein said means includes an elongated polymer filament having a cross sectional dimension, the filament capable of being elongated to reduce the cross sectional dimension.

7. The implantable device according to claim 6, further including a capillary in fluid communication between said chamber and said outlet, wherein the filament is located centrally within said capillary.

8. The implantable device according to claim 6, further including a capillary in fluid communication between said chamber and said outlet, wherein the filament is located eccentrically within said capillary.

9. The implantable device according to claim 8, wherein the filament has a uniform cross section along its length.

10. The implantable device according to claim 9, wherein the filament has a substantially circular cross section.

11. The implantable device according to claim 8, wherein the filament has a non-uniform cross section along its length.

12. The implantable device according to claim 6, further comprising means for elongating the filament.

13. The implantable device according to claim 12, wherein said means for elongating the filament includes at least two magnetic elements.

14. The implantable device according to claim 12, wherein said means for elongating the filament includes an axle.

15. The implantable device according to claim 1, wherein said means includes a first hollow cylinder having a threaded exterior surface and a second hollow cylinder having a threaded interior surface, said first hollow cylinder axially received within said second hollow cylinder, wherein the threaded exterior surface of the first cylinder engages the threaded interior surface of the second cylinder.

16. The implantable device according to claim 15, wherein the axial movement of the first cylinder with respect to the second cylinder varies the flow rate of said active substance.

17. The implantable device according to claim 1, wherein said means includes a hollow tubular element having a cross section that is capable of being varied.

18. The implantable device according to claim 17, further including a capillary in fluid communication between said chamber and said outlet, wherein the hollow tubular element is located centrally within said capillary.

19. The implantable device according to claim 17, further including a capillary in fluid communication between said chamber and said outlet, wherein the hollow tubular element is located eccentrically within said capillary.

20. The implantable device according to claim 1, wherein said means includes an elongate insert having a longitudinally varying cross section along its length.

21. The implantable device according to claim 1, further comprising means for controlling said means for varying the flow rate of said active substance between said chamber and said outlet.

22. The implantable device according to claim 18, wherein the means for controlling are wireless.

23. An implantable device for dispensing an active substance to a patient comprising:

a housing defining a chamber, said housing having an outlet for delivering said active substance to a target site within said patient, said outlet in fluid communication with the chamber;

a capillary in fluid communication between said chamber and said outlet, said capillary having an inner surface; and

a flow control element received within said capillary, said element having an outer surface opposing said inner surface of said capillary defining therebetween a passageway for the flow of said active substance therethrough, said outer surface of said element moveable relative to said inner surface of said capillary to alter the flow of said active substance therethrough.

24. The implantable device according to claim 23, wherein movement of said outer surface of said element alters the size of said passageway.

25. The implantable device according to claim 23, wherein movement of said outer surface of said element alters the shape of said passageway.

26. The implantable device according to claim 23, wherein said flow control element is an elongated polymer filament having a cross sectional dimension, the filament capable of being elongated to reduce the cross sectional dimension.

27. The implantable device according to claim 26, wherein the filament is located centrally within said capillary.

28. The implantable device according to claim 26, wherein the filament is located eccentrically within said capillary.

29. The implantable device according to claim 26, wherein the filament has a uniform cross section along its length.

30. The implantable device according to claim 29, wherein the filament has a substantially circular cross section.

31. The implantable device according to claim 26, wherein the filament has a non-uniform cross section along its length.

32. The implantable device according to claim 26, further comprising means for elongating the filament.

33. The implantable device according to claim 32, wherein said means for elongating the filament includes at least two magnetic elements.

34. The implantable device according to claim 32, wherein said means for elongating the filament includes an axle.

35. The implantable device according to claim 23, wherein said flow control element is a first hollow cylinder having a threaded exterior surface and said capillary includes a threaded interior surface, said first hollow cylinder axially received within said capillary, wherein the threaded exterior surface of the first cylinder engages the threaded interior surface of the capillary.

36. The implantable device according to claim 35, wherein the axial movement of the first cylinder with respect to the capillary varies the flow rate of said active substance.

37. The implantable device according to claim 23, wherein said flow control element is a hollow tubular element having a cross section that is capable of being varied.

38. The implantable device according to claim 37, wherein the hollow tubular element is located centrally within said capillary.

39. The implantable device according to claim 37, wherein the hollow tubular element is located eccentrically within said capillary.

40. The implantable device according to claim 23, wherein said flow control element is an elongate insert having a longitudinally varying cross section along its length.

41. The implantable device according to claim 23, further comprising means for controlling the movement of said flow control element.

42. The implantable device according to claim 41, wherein the means for controlling are wireless.

43. A resistor for varying the flow rate of a fluid from a first point to a second point comprising:

a capillary having an inner surface;

a flow control element received within said capillary, said element having an outer surface opposing said inner surface of said capillary defining therebetween a passage way for the flow of said fluid therethrough, said outer surface of said element moveable relative to said inner surface of said capillary to alter the flow of said fluid therethrough.

44. The resistor according to claim 43, wherein movement of said inner surface of said capillary alters the size of said passageway.

45. The resistor according to claim 43, wherein movement of said inner surface of said capillary alters the shape of said passageway.

46. The resistor according to claim 43, wherein said flow control element is an elongated polymer filament having a cross sectional dimension, the filament capable of being elongated to reduce the cross sectional dimension.

47. The resistor according to claim 46, wherein the filament is located centrally within said capillary.

48. The resistor according to claim 46, wherein the filament is located eccentrically within said capillary.

49. The resistor according to claim 46, wherein the filament has a uniform cross section along its length.

50. The resistor according to claim 49, wherein the filament has a substantially circular cross section.

51. The resistor according to claim 46, wherein the filament has a non-uniform cross section along its length.

52. The resistor according to claim 46, further comprising means for elongating the filament.

53. The resistor according to claim 52, wherein said means for elongating the filament includes at least two magnetic elements.

54. The resistor according to claim 52, wherein said means for elongating the filament includes an axle.

55. The resistor according to claim 43, wherein said flow control element is a first hollow cylinder having a threaded exterior surface and said capillary includes a threaded interior surface, said first hollow cylinder axially received within said capillary, wherein the threaded exterior surface of the first cylinder engages the threaded interior surface of the capillary.

56. The resistor according to claim 55, wherein the axial movement of the first cylinder with respect to the capillary varies the flow rate of said active substance.

57. The resistor according to claim 43, wherein said flow control element is a hollow tubular element having a cross section that is capable of being varied.

58. The resistor according to claim 57, wherein the hollow tubular element is located centrally within said capillary.

59. The resistor according to claim 57, wherein the hollow tubular element is located eccentrically within said capillary.

60. The resistor according to claim 43, wherein said flow control element is an elongate insert having a longitudinally varying cross section along its length.

61. The resistor according to claim 43, further comprising means for controlling the movement of said flow control element.

62. The resistor according to claim 61, wherein the means for controlling are wireless.

63. The resistor according to claim 43, wherein said resistor is adapted to be connected with an implantable device for dispensing an active substance to a patient.

64. A method of varying the flow rate of an active substance being dispensed to a patient comprising:

providing an implantable device including a capillary having an inner surface and a flow control element received within said capillary, said element having an outer surface opposing said inner surface of said capillary defining therebetween a passageway for the flow of said active substance therethrough to a target site within a patient; and

moving said element relative to said inner surface of said capillary to alter the flow rate of said active substance therethrough.

65. The method according to claim 64, wherein said moving step alters the size of said passageway.

66. The method according to claim 64, wherein said moving step alters the size of said passageway.

67. A method of converting an implantable pump from an infinitely variable pump to a fixed flow rate pump comprising:

providing an implantable pump having a housing defining a chamber, an outlet, and a capillary in fluid communication between said chamber and said outlet, said capillary further including a flow control element received within said capillary for varying the flow rate of an active substance between said chamber and said outlet;

removing said flow control element from said capillary; and

placing a tubular element within said capillary, said tubular element being situated so that fluid from said chamber flows through said tubular element prior to exiting said outlet.

68. The method according to claim 67, wherein said tubular element is a glass tube having an outer diameter which allows it to fit within said capillary and an inner diameter which provides a desired flow rate from said chamber to said outlet.

69. The method according to claim 67, wherein said flow control element is an elastic filament being capable of being elongated to reduce a cross sectional dimension.

70. The method according to claim 69, further comprising the step of removing a module including means for elongating said elastic filament.

71. The method according to claim 70, wherein said means for elongating said elastic filament include a motor and a power source.