Light barrier for medical electrical lead oxygen sensor

• US 6,125,291 A
• Filed: 10/30/1998
• Issued: 09/26/2000
• Est. Priority Date: 10/30/1998
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Stetz, Eric M., Miesel, Keith A.
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US09/182,764
• Time in Patent Office: 697 Days
• Field of Search: 600/322, 600/323, 600/324, 600/325, 600/332, 600/333, 600/335, 600/341, 607/22, 607/122
• US Class Current: 600/333
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/6864 Burr holes
• CPC Class Codes: A61N 1/36557 controlled by chemical substances in blood

Abstract

An implantable sensor assembly for use with an implantable medical device are disclosed. The sensor assembly preferably includes two or more physiologic sensors coupled to the medical device via a pair of lead conductors, or alternatively an oxygen sensor having certain features. The oxygen sensor permits more accurate and reliable measurement of oxygen saturation in blood masses flowing within the human body.

Claims

1. A body implantable medical electrical lead adapted to be implanted in a living body in operative relation with oxygenated body fluid, comprising:

(a) a lead body having proximal and distal ends and comprising an electrically insulative material;

(b) at least first and second electrical conductors disposed within at least portions of the lead body, the conductors having at least portions of the electrically insulative material disposed therebetween;

(c) an oxygen sensor attached to the lead body and coupled electrically with said first and second lead conductors, comprising;

(i) a housing having proximal and distal ends, an exterior, and first and second interior portions disposed therewithin;

(ii) a light emitter disposed within the first interior portion of the housing;

(iii) a light detector disposed within the second interior portion of the housing;

(iv) a light transmissive first lens disposed over the light emitter and mounted in the housing between the exterior and the first interior portion of the housing to enable at least portions of light emitted by the light emitter to pass through the first lens from the first interior portion to the exterior;

(v) a light transmissive second lens disposed over the light detector and mounted in the housing between the exterior and the second interior portion of the housing to enable at least portions of light emitted by the light emitter through the first lens and reflecting from oxygenated body fluid adjacent to at least portions of the housing exterior to pass through the second lens from the exterior to the second interior portion, the first and second lenses being separated and spaced apart from one another; and

(vi) a light barrier positioned between the first interior portion and the second interior portion, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough into the second interior portion for detection by the light detector.

2. The body implantable medical electrical lead of claim 1, wherein the light barrier is further positioned between the first lens and the second lens, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough for detection by the light detector.

3. The body implantable medical electrical lead of claim 1, wherein the light barrier is one of a membrane and a gasket.

4. The body implantable medical electrical lead of claim 1, wherein the light barrier includes one of a membrane and a gasket.

5. The body implantable medical electrical lead of claim 1, wherein the light barrier includes at least a portion of the housing.

6. The body implantable medical electrical lead of claim 1, wherein the housing is elongated.

7. The body implantable medical electrical lead of claim 1, wherein the light barrier includes surfaces configured to guide or reflect light towards the light detector.

8. The body implantable medical electrical lead of claim 7, wherein the surfaces are reflective.

9. The body implantable medical electrical lead of claim 7, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

10. The body implantable medical electrical lead of claim 7, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

11. The body implantable medical electrical lead of claim 7, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

12. The body implantable medical electrical lead of claim 7, wherein the surfaces are coated with highly reflective material.

13. The body implantable medical electrical lead of claim 1, wherein the light barrier includes surfaces configured to guide or reflect light emitted by the light emitter towards the first lens.

14. The body implantable medical electrical lead of claim 13, wherein the surfaces are reflective.

15. The body implantable medical electrical lead of claim 13, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

16. The body implantable medical electrical lead of claim 13, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

17. The body implantable medical electrical lead of claim 13, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

18. The body implantable medical electrical lead of claim 13, wherein the surfaces are coated with highly reflective material.

19. The body implantable medical electrical lead of claim 1, wherein at least portions of the light barrier are formed of silicone.

20. The body implantable medical electrical lead of claim 1, wherein at least one of the first and second lenses comprises one of sapphire, ruby and glass.

21. The body implantable medical electrical lead of claim 1, wherein the housing comprises a metal selected from the group consisting of titanium, stainless steel, platinum, niobium, and alloys or combinations thereof.

22. The body implantable medical electrical lead of claim 1, wherein the lead further comprises at least a first electrode for stimulation of cardiac tissue disposed one of near and at the distal end of the lead body.

23. The body implantable medical electrical lead of claim 22, wherein the oxygen sensor attached to the lead body is disposed proximally of the first electrode.

24. The body implantable medical electrical lead of claim 22, wherein the first electrode is a tip electrode.

25. The body implantable medical electrical lead of claim 22, wherein the lead further includes a second electrode.

26. The body implantable medical electrical lead of claim 25, wherein the second electrode is a ring electrode.

27. An implantable medical device system, comprising:

(a) an implantable medical device adapted to be implanted in a living body;

(b) a body implantable medical electrical lead attached to the implantable medical device adapted to be implanted in a living body in operative relation with oxygenated body fluid, the lead comprising;

(i) a lead body having proximal and distal ends and comprising an electrically insulative material, the proximal end of the lead being attached to the implantable medical device;

(ii) at least first and second electrical conductors disposed within at least portions of the lead body, the conductors having at least portions of the electrically insulative material disposed therebetween;

(iii) an oxygen sensor attached to the lead body and coupled electrically with said first and second lead conductors, comprising;

(1) a housing having proximal and distal ends, an exterior, and first and second interior portions disposed therewithin;

(2) a light emitter disposed within the first interior portion of the housing;

(3) a light detector disposed within the second interior portion of the housing;

(4) a light transmissive first lens disposed over the light emitter and mounted in the housing between the exterior and the first interior portion of the housing to enable at least portions of light emitted by the light emitter to pass through the first lens from the first interior portion to the exterior; and

(5) a light transmissive second lens disposed over the light detector and mounted in the housing between the exterior and the second interior portion of the housing to enable at least portions of light emitted by the light emitter through the first lens and reflecting from oxygenated body fluid adjacent to at least portions of the housing exterior to pass through the second lens from the exterior to the second interior portion, the first and second lenses being separated and spaced apart from one another; and

(6) a light barrier positioned between the first interior portion and the second interior portion, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough into the second interior portion for detection by the light detector.

28. The implantable medical device system of claim 27, wherein the implantable medical device is selected from the group consisting of a heart monitor, a therapy delivery device, a pacemaker, an implantable pulse generator, a pacer-cardio-defibrillator, an implantable cardio-defibrillator, a cardiomyo-stimulator, a nerve stimulator, a brain stimulator, a gastric stimulator and a drug delivery device.

29. The implantable medical device system of claim 27, wherein the light barrier is further positioned between the first lens and the second lens, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough for detection by the light detector.

30. The implantable medical device system of claim 27, wherein the light barrier is one of a membrane and a gasket.

31. The implantable medical device system of claim 27, wherein the light barrier includes one of a membrane and a gasket.

32. The implantable medical device system of claim 27, wherein the light barrier includes at least a portion of the housing.

33. The implantable medical device system of claim 27, wherein the housing is elongated.

34. The implantable medical device system of claim 27, wherein the light barrier includes surfaces configured to guide or reflect light towards the light detector.

35. The implantable medical device system of claim 34, wherein the surfaces are reflective.

36. The implantable medical device system of claim 34, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

37. The implantable medical device system of claim 34, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

38. The implantable medical device system of claim 34, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

39. The implantable medical device system of claim 34, wherein the surfaces are coated with highly reflective material.

40. The implantable medical device system of claim 27, wherein the light barrier includes surfaces configured to guide or reflect light emitted by the light emitter towards the first lens.

41. The implantable medical device system of claim 40, wherein the surfaces are reflective.

42. The implantable medical device system of claim 40, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

43. The implantable medical device system of claim 40, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

44. The implantable medical device system of claim 40, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

45. The implantable medical device system of claim 40, wherein the surfaces are coated with highly reflective material.

46. The implantable medical device system of claim 27, wherein at least portions of the light barrier are formed of silicone.

47. The implantable medical device system of claim 27, wherein at least one of the first and second lenses comprises one of sapphire, ruby and glass.

48. The body implantable medical electrical lead of claim 27, wherein the housing comprises a metal selected from the group consisting of titanium, stainless steel, platinum, niobium, and alloys or combinations thereof.

49. The implantable medical device system of claim 27, wherein the lead further comprises at least a first electrode for stimulation of cardiac tissue disposed one of near and at the distal end of the lead body.

50. The implantable medical device system of claim 49, wherein the oxygen sensor attached to the lead body is disposed proximally of the first electrode.

51. The implantable medical device system of claim 49, wherein the first electrode is a tip electrode.

52. The implantable medical device system of claim 49, wherein the lead further includes a second electrode.

53. The implantable medical device system of claim 52, wherein the second electrode is a ring electrode.

54. A body implantable medical oxygen sensor adapted to be implanted in a living body in operative relation with oxygenated body fluid, comprising:

(a) a housing having proximal and distal ends, an exterior, and first and second interior portions disposed therewithin;

(b) a light emitter disposed within the first interior portion of the housing;

(c) a light detector disposed within the second interior portion of the housing;

(d) a light transmissive first lens disposed over the light emitter and mounted in the housing between the exterior and the first interior portion of the housing to enable at least portions of light emitted by the light emitter to pass through the first lens from the first interior portion to the exterior;

(e) a light transmissive second lens disposed over the light detector and mounted in the housing between the exterior and the second interior portion of the housing to enable at least portions of light emitted by the light emitter through the first lens and reflecting from oxygenated body fluid adjacent to at least portions of the housing exterior to pass through the second lens from the exterior to the second interior portion, the first and second lenses being separated and spaced apart from one another; and

(f) a light barrier positioned between the first interior portion and the second interior portion, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough into the second interior portion for detection by the light detector.

55. The implantable oxygen sensor of claim 54, wherein the light barrier is further positioned between the first lens and the second lens, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough for detection by the light detector.

56. The implantable oxygen sensor of claim 54, wherein the light barrier is one of a membrane and a gasket.

57. The implantable oxygen sensor of claim 54, wherein the light barrier includes one of a membrane and a gasket.

58. The implantable oxygen sensor of claim 54, wherein the light barrier includes at least a portion of the housing.

59. The implantable oxygen sensor of claim 54, wherein the housing is elongated.

60. The implantable oxygen sensor of claim 54, wherein the light barrier includes surfaces configured to guide or reflect light towards the light detector.

61. The implantable oxygen sensor of claim 60, wherein the surfaces are reflective.

62. The implantable oxygen sensor of claim 60, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

63. The implantable oxygen sensor of claim 60, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

64. The implantable oxygen sensor of claim 60, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

65. The implantable oxygen sensor of claim 60, wherein the surfaces are coated with highly reflective material.

66. The implantable oxygen sensor of claim 54, wherein the light barrier includes surfaces configured to guide or reflect light emitted by the light emitter towards the first lens.

67. The implantable oxygen sensor of claim 66, wherein the surfaces are reflective.

68. The implantable oxygen sensor of claim 66, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted by the light emitter.

69. The implantable oxygen sensor of claim 66, wherein the surfaces are shaped to at least one of collimate and reflect outwardly light emitted sideways by the light emitter.

70. The implantable oxygen sensor of claim 66, wherein the surfaces are least one of one of slanted, sloped and parabolically shaped.

71. The implantable oxygen sensor of claim 66, wherein the surfaces are coated with highly reflective material.

72. The implantable oxygen sensor of claim 54, wherein at least portions of the light barrier are formed of silicone.

73. The implantable medical device system of claim 54, wherein at least one of the first and second lenses comprises one of sapphire, ruby and glass.

74. The body implantable medical electrical lead of claim 54, wherein the housing comprises a metal selected from the group consisting of titanium, stainless steel, platinum, niobium, and alloys or combinations thereof.

75. A method of making a body implantable medical electrical lead adapted to be implanted in a living body in operative relation with oxygenated body fluid, the lead comprising a lead body having proximal and distal ends, an electrically insulative material, at least first and second electrical conductors disposed within at least portions of the lead body, the conductors having at least portions of the electrically insulative material disposed therebetween, an oxygen sensor being attached to the lead body and coupled electrically with said first and second lead conductors and comprising a housing having proximal and distal ends, an exterior, and first and second interior portions disposed therewithin, a light emitter disposed within the first interior portion of the housing, a light detector disposed within the second interior portion of the housing, a light transmissive first lens disposed over the light emitter and mounted in the housing between the exterior and the first interior portion of the housing to enable at least portions of light emitted by the light emitter to pass through the first lens from the first interior portion to the exterior, and a light transmissive second lens disposed over the light detector and mounted in the housing between the exterior and the second interior portion of the housing to enable at least portions of light emitted by the light emitter through the first lens and reflecting from oxygenated body fluid adjacent to at least portions of the housing exterior to pass through the second lens from the exterior to the second interior portion, the first and second lenses being separated and spaced apart from one another, and a light barrier positioned between the first interior portion and the second interior portion, the light barrier not permitting light emitted by the light emitter to be transmitted therethrough into the second interior portion for detection by the light detector, the method comprising the steps of:

(a) providing the lead body;

(b) providing the oxygen sensor, and

(c) attaching the oxygen sensor to the lead body.

76. The method of claim 75, wherein the method further comprises the step of forming the lead body.

77. The method of claim 75, wherein the method further comprises the step of forming the oxygen sensor.

78. The method of claim 77, wherein the oxygen sensor forming step further comprises the step of including the light barrier between the first and second interior portions.

79. The method of claim 77, wherein the oxygen sensor forming step further comprises the step of including the light barrier between the first and second lenses.

80. A body implantable medical electrical lead adapted to be implanted in a living body in operative relation with oxygenated body fluid, comprising:

(a) a lead body having proximal and distal ends and comprising an electrically insulative material;

(b) at least first and second electrical conductors disposed within at least portions of the lead body, the conductors having at least portions of the electrically insulative material disposed therebetween;

(c) an oxygen sensor attached to the lead body and coupled electrically with said first and second lead conductors, comprising;

(i) a housing having proximal and distal ends, an exterior, and first and second interior portions disposed therewithin;

(ii) a light emitter disposed within the first interior portion of the housing;

(iii) a light detector disposed within the second interior portion of the housing;

(iv) a light transmissive first lens disposed over the light emitter to enable at least portions of light emitted by the light emitter to pass through the first lens from the first interior portion to the exterior, the first lens having an interior surface disposed toward the first interior portion and having an a first index of refraction;

(v) a light transmissive second lens disposed over the light detector to enable at least portions of light emitted by the light emitter and reflecting from oxygenated body fluid adjacent to at least portions of the housing exterior to pass through the second lens from the exterior to the second interior portion and to the light detector, the second lens having an interior surface disposed toward the second interior portion and having a second index of refraction; and

(v) a light barrier comprising a coating disposed over at least portions of the interior surface of at least one of the first and second lenses, the coating being one of a high index of refraction coating and an anti-reflective coating, the high index of refraction coating having an index of refraction that is less than the index of refraction of the first or second lens that the high index of refraction coating is disposed over, the anti-reflective coating having an index of refraction that is less than the index of refraction of the first or second lens that the high index of refraction coating is disposed over, whereby light emitted by the light emitter is not refracted or reflected through the first and second lenses into the second interior portion and detected by the light detector.

81. The body implantable medical electrical lead of claim 80, wherein the sensor housing is elongated and tubular, the light transmissive first lens and second lens are formed of first and second portions of a light transmissive, elongated tubular lens element disposed over the light emitter within the first interior portion and the light detector within the second interior portion, respectively, and mounted to the housing between the exterior and first interior portions of the housing such that at least portions of light emitted by the light emitter pass through the first lens from the first interior portion to the exterior and the anti-reflective coating or the high index of refraction coating is applied upon an interior surface portion of the tubular lens element to inhibit reflection or refraction of emitted light through the tubular lens element and into the second interior portion.

82. The body implantable medical electrical lead of claim 81, wherein the first and second lenses are separated and spaced apart from one another and mounted in said housing.

83. The body implantable medical electrical lead of claim 82, wherein the light barrier further comprises light blocking means positioned between the first lens and the second lens for blocking light emitted by the light emitter from being transmitted therethrough for detection by the light detector.

84. The body implantable medical electrical lead of claim 83, wherein the light blocking means is one of a membrane and a gasket.

85. The body implantable medical electrical lead of claim 83, wherein the light blocking means includes one of a membrane and a gasket.

86. The body implantable medical electrical lead of claim 83, wherein the light blocking means includes at least a portion of the housing, and the housing is formed of a material that blocks transmission of light emitted by the light emitter.

87. The body implantable medical electrical lead of claim 83, wherein at least portions of the light blocking means are formed of silicone.

88. The body implantable medical electrical lead of claim 80, wherein the housing is elongated.

89. The body implantable medical electrical lead of claim 80, wherein the at least one lens comprises one of sapphire, ruby and glass.

90. The body implantable medical electrical lead of claim 80, wherein the housing comprises a metal selected from the group consisting of titanium, stainless steel, platinum, niobium, and alloys or combinations thereof.

91. The body implantable medical electrical lead of claim 80, wherein the lead further comprises at least a first electrode for stimulation of cardiac tissue disposed one of near and at the distal end of the lead body.

92. The body implantable medical electrical lead of claim 91, wherein the oxygen sensor attached to the lead body is disposed proximally of the first electrode.

93. The body implantable medical electrical lead of claim 91, wherein the first electrode is a tip electrode.

94. The body implantable medical electrical lead of claim 91, wherein the lead further includes a second electrode.

95. The body implantable medical electrical lead of claim 94, wherein the second electrode is a ring electrode.