Medical Diagnostic and Treatment Platform Using Near-Field Wireless Communication of Information Within a Patient's Body

• US 20080306359A1
• Filed: 09/01/2006
• Published: 12/11/2008
• Est. Priority Date: 09/01/2005
• Status: Active Grant

• Current Assignee: Otsuka Pharmaceutical Company Limited (Otsuka Holdings Company Limited)
• Original Assignee: Proteus Digital Health, Inc. (Otsuka Holdings Company Limited)
• Inventors: Zdeblick, Mark J., Robertson, Timothy
• Granted Patent: US 8,547,248 B2
• Time in Patent Office: Days
• US Class Current: 600/302
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0028 Body tissue as transmission medium, i.e. transmission systems where the medium is the human body
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/0265 using electromagnetic means, e.g. electromagnetic flowmeter
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14535 for measuring haematocrit
• CPC Class Codes: A61B 5/415 the glands, e.g. tonsils, adenoids or thymus
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: A61B 5/6862 Stents
• CPC Class Codes: A61B 5/6876 Blood vessel
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

The present invention provides implantable systems that communicate wirelessly with each other using a unique format that enables devices configurations and applications heretofore not possible. Embodiments of the present invention provide communication apparatuses and methods for exchanging information with implantable medical devices. In some embodiments, two implantable devices communicate with each other using quasi-electrostatic signal transmission in a long wavelength/low frequency electromagnetic band, with the patient'"'"'s body acting as a conductive medium.

Claims

1. A system for communicating information within the body of animal, the system comprising:

(a) a first device comprising a transmitter configured to transmit a signal via a quasi electrostatic coupling to the body of the patient; and

(b) a second device comprising a receiver configured to receive the transmitted signal via a quasi electrostatic coupling to the body of the patient.

2. The system according to claim 1, wherein said system includes at least a third device which is configured to at least one of:

(i) transmit a signal via a quasi electrostatic coupling to the body of the patient; and

(ii) receive the transmitted signal via a quasi electrostatic coupling to the body of the patient.

3. The system according to claim 1, wherein said signal comprises data produced by said first device.

4. The system according to claim 1, wherein said signal comprises an identifier of said first device.

5. The system according to claim 1, wherein said signal is used by said second device as a power source.

6. The system according to claim 1, wherein said first device is an implantable medical device.

7. The system according to claim 6, wherein said first device includes a sensor.

8. The system according to claim 7, wherein said sensor is a blood flow sensor.

9. The system according to claim 8, wherein said blood flow sensor comprises a resistivity sensor.

10. The system according to claim 8, wherein said blood flow sensor comprises an electromagnetic blood flow sensor.

11. The system according to claim 6, wherein said first device includes an effector.

12. The system according to claim 11, wherein said effector comprises an electrode.

13. The system according to claim 1, wherein the first device comprises an ingestible medical device.

14. The system according to claim 1, wherein the first device is an external device configured to contact a surface of said animal.

15. The system according to claim 1, wherein the second device is an implantable medical device.

16. The system according to claim 15, wherein the second device is further configured to retransmit the received signal to a secondary receiver external to said patient.

17. The system according to claim 16, wherein said secondary receiver is an RF receiver and comprises a radio frequency (RF) transmitter.

18. The system according to claim 16, wherein said second device includes a transcutaneous wire configured to retransmit the received information to the secondary receiver.

19. The system according to claim 16, wherein said secondary receiver is internal to said patient.

20. The system according to claim 1, wherein the second device is a pacemaker.

64. The implantable blood flow sensor according to claim 55, wherein said sensor is part of a system according to claim 1.

95. The implantable fluid flow sensor according to claim 83, wherein said sensor is part of a system according to claim 1.

21. A communications device for use within a body of a patient, said communications device comprising:

(a) a power supply;

(b) a signal generating circuit coupled to said power supply and configured to generate a signal; and

(c) an antenna coupled to said signal generating circuit and configured to transmit said signal via quasi electrostatic coupling to said body.

22. The communications device according to claim 21, wherein said power supply comprises a battery.

23. The communications device according to claim 21, wherein said power supply comprises:

(i) an antenna configured to receive energy from an energy source via a quasi electrostatic coupling to said body; and

(ii) a converter circuit configured to convert the received energy to electrical power.

24. The communications device according to claim 21, wherein said antenna comprises a pair of electrodes separated by a gap.

25. The communications device according to claim 21, wherein said signal generating circuit is further configured to generate a signal representing information.

26. The communications device according to claim 25, wherein said signal generating circuit comprises an oscillator coupled to said antenna.

27. The communications device according to claim 26, wherein said oscillator is configured to operate at a frequency such that a radiation field generated by the antenna has a wavelength more than 10 times longer than a largest dimension of said body.

28. The communications device according to claim 27, wherein said oscillator is configured to operate at a frequency of about 10 MHz or less.

29. The communications device according to claim 28, wherein said oscillator is configured to operate at a frequency of between about 300 Hz and about 1 MHz.

30. The communications device according to claim 21, wherein said signal generating circuit comprises:

(i) a driver coupled to drive a time varying potential on said antenna;

(ii) an oscillator having an output coupled to said driver; and

(iii) a modulator configured to modulate a frequency of the oscillator output so as to encode the information.

31. The communications device according to claim 21, wherein said signal generating circuit comprises:

(i) a driver coupled to drive a time varying potential on said antenna;

(ii) an oscillator having an output coupled to said driver; and

(ii) a modulator configured to modulate a phase of said oscillator output so as to encode the information.

32. The communications device according to claim 21, wherein said signal generating circuit includes:

(i) a driver coupled to drive a time varying potential on said antenna;

(ii) an oscillator having an output coupled to said driver; and

(iii) a modulator configured to modulate an amplitude of said oscillator output so as to encode the information.

33. The communications device according to claim 21, wherein device is an implantable medical device.

34. The communications device according to claim 33, wherein said device includes a sensor.

35. The communications device according to claim 34, wherein said sensor is a blood flow sensor.

36. The communications device according to claim 35, wherein said blood flow sensor comprises a resistivity sensor.

37. The communications device according to claim 35, wherein said blood flow sensor comprises an electromagnetic blood flow sensor.

38. The communications device according to claim 33, wherein said device includes an effector.

39. The communications device according to claim 38, wherein said effector comprises an electrode.

40. The communications device according to claim 21, wherein the device is an ingestible medical device.

41. The communications device according to claim 21, wherein said device is a pharmaceutical delivery device.

42. A method for communicating information within a body of a patient, said method comprising:

(a) operating a transmitter of a device located within said body to generate a quasi electrostatic signal; and

(b) detecting said quasi electrostatic signal using a receiver.

43. The method according to claim 42, wherein said receiver is disposed within said body.

44. The method according to claim 42, wherein said receiver is in contact with an external surface of said body.

45. The method according to claim 42, wherein said device is an implantable medical device.

46. The method according to claim 45, wherein said device includes a sensor.

47. The method according to claim 46, wherein said sensor is a blood flow sensor.

48. The method according to claim 47, wherein said blood flow sensor is a resistivity sensor.

49. The method according to claim 47 wherein said blood flow sensor is an electromagnetic blood flow sensor.

50. The method according to claim 45, wherein said device includes an effector.

51. The method according to claim 50, wherein said actuator comprises an electrode.

52. The method according to claim 42, wherein the device is an ingestible medical device.

53. A kit comprising at least one of:

(a) a first device comprising a transmitter configured to transmit a signal via a quasi electrostatic coupling to a body of a patient; and

(b) a second device comprising a receiver configured to receive the transmitted signal via a quasi electrostatic coupling to said body.

54. The kit according to claim 53, wherein said kit comprises both of said first and second devices.

55. An implantable fluid flow sensor comprising:

(a) a substrate;

(b) a pair of current flow electrodes disposed on a top surface of said substrate;

(c) a current source on said substrate and configured to transfer charge between said first and second current flow electrodes;

(d) a pair of sense electrodes disposed on said top surface of the substrate between said flow terminals and separated by a distance S; and

(e) a detection circuit on said substrate configured to;

(i) detect a potential difference between said sense electrodes, the potential difference correlating to a resistivity of flowing blood, and

(ii) produce an output signal at an output node, the output signal correlating to the potential difference.

56. The implantable blood flow sensor according to claim 55, further comprising a transmitter unit coupled to said output node of the detection circuit and configured to transmit said output signal to a data collector.

57. The implantable blood flow sensor according to claim 56, wherein said transmitter unit is configured to transmit via quasi electrostatic coupling into a conductive tissue of a body of a patient.

58. The implantable blood flow sensor according to claim 55, further comprising a power supply unit configured to supply power to said current source and said detection circuit.

59. The implantable blood flow sensor according to claim 55, wherein said distance S is about 10 microns or less.

60. The implantable blood flow sensor according to claim 55, wherein said detection circuit is further configured to detect discrete potential variations resulting from passage of individual red blood cells.

61. The implantable blood flow sensor according to claim 55, wherein said sensor is present on a lead.

62. The implantable blood flow sensor according to claim 61, wherein said lead is a multiplex lead.

63. The implantable blood flow sensor according to claim 55, wherein said sensor is not present on a lead.

65. The implantable blood flow sensor according to claim 55, wherein said sensor is configured to detect a potential difference at two different frequencies.

66. A method of determining a physiological parameter of a patient, said method comprising:

(a) obtaining a resistivity measure from a fluid flow sensor implanted in a blood vessel of said a patient; and

(b) processing said resistivity measure to determine said physiological parameter.

67. The method according to claim 66, wherein said processing is performed by a data collector.

68. The method according to claim 67, wherein said data collector is remote from said sensor.

69. The method according to claim 68, wherein said resistivity measure is wirelessly communicated from said sensor to said data collector using a wireless communication protocol.

70. The method according to claim 69, wherein said wireless communication protocol comprises using quasi electrostatic coupling to a conductive tissue of said patient.

71. The method according to claim 67, wherein said data collector is implanted in or attached to the patient'"'"'s body.

72. The method according to claim 71, wherein said data collector is part of a pacemaker can.

73. The method according to claim 72, wherein said data collector comprises a wearable unit including electrodes attachable to the patient'"'"'s skin and configured to detect quasi electrostatic signals propagating in the body of the patient.

74. The method according to claim 66, wherein said physiological parameter corresponds to a blood flow velocity.

75. The method according to claim 66, wherein said physiological parameter corresponds to hematocrit.

76. The method according to claim 66, wherein said physiological parameter corresponds to a stroke volume.

77. The method according to claim 66, further comprising performing a remedial action based on said physiological parameter.

78. The method according to claim 77, wherein said remedial action comprises administering a pharmaceutical agent to said patient.

79. The method according to claim 78, wherein said remedial action comprises administering a electrical stimulation to said patient.

80. The method according to claim 78, wherein said remedial action comprises alerting said patient to seek medical attention.

81. The method according to claim 66, wherein said method comprises detecting a potential difference at two different frequencies.

82. A kit comprising:

(A) an implantable blood flow sensor comprising;

(i) a substrate;

(ii) a pair of current flow electrodes disposed on a top surface of said substrate;

(iii) a current source on said substrate and configured to transfer charge between said first and second current flow electrodes;

(iv) a pair of sense electrodes disposed on said top surface of the substrate between said flow terminals and separated by a distance S; and

(v) a detection circuit on said substrate configured to;

(a) detect a potential difference between said sense electrodes, the potential difference correlating to a resistivity of flowing blood, and

(b) produce an output signal at an output node, the output signal correlating to the potential difference; and

(B) a data collector.

83. An implantable fluid flow sensor comprising:

(a) a pair of sense electrodes; and

(b) a detection circuit configured to;

(i) detect a potential difference between said sense electrodes, the potential difference resulting from an applied magnetic field to flowing fluid, and

(ii) produce an output signal at an output node, the output signal correlating to the detected potential difference.

84. The implantable fluid flow sensor according to claim 83, wherein said applied magnetic field is an alternating current magnetic field having an alternating frequency and said detection circuit is configured to detect said potential difference at said alternating frequency.

85. The implantable fluid flow sensor according to claim 83, wherein said sensor further comprises a magnetic field production element.

86. The implantable fluid flow sensor according to claim 85, wherein said magnetic field production element comprises at least one pair of coils.

87. The implantable fluid flow sensor according to claim 86, wherein said sensor further comprises a solid support and said pair of sense electrodes and pair of coils are present a same surface of said solid support.

88. The implantable fluid flow sensor of claim 87, wherein said solid support is a structure having a planar surface and said sense electrodes and coils are present on said planar surface.

89. The implantable fluid flow sensor of claim 87, wherein said solid support is a structure having a curvilinear surface, and said sense electrodes and coils are present on said curvilinear surface.

90. The implantable fluid flow sensor of claim 89, wherein said solid support is a stent and said curvilinear surface is the inner surface of said stent.

91. The implantable fluid flow sensor of claim 89, wherein said solid support is a lead and said curvilinear surface is the outer surface of said lead.

92. The implantable fluid flow sensor of claim 83, wherein said sense electrodes are present on a lead.

93. The implantable fluid flow sensor of claim 92, wherein said lead is a multiplex lead.

94. The implantable fluid flow sensor according to claim 83, wherein said sense electrodes are not present on a lead.

96. A method of determining a physiological parameter of a patient, said method comprising:

(a) applying a magnetic field to a target fluid flow site of said patient;

(b) obtaining a potential difference measure from a pair of sense electrodes positioned at said target fluid flow site; and

(b) processing said potential difference measure to determine said physiological parameter.

97. The method according to claim 96, wherein said magnetic field is applied to said target fluid flow site from a magnetic field source external to said patient.

98. The method according to claim 96, wherein said magnetic field is applied to said target fluid flow site from a magnetic field source internal to said patient.

99. The method according to claim 98, wherein said magnetic filed source and said sense electrodes are both present on a surface of a solid support.

100. The method according to claim 99, wherein said surface is a planar surface.

101. The method according to claim 99, wherein said surface is a curvilinear surface.

102. The method according to claim 96, wherein said processing is performed by a data collector.

103. The method according to claim 102, wherein said data collector is remote from said sense electrodes.

104. The method according to claim 103, wherein said potential difference measure is wirelessly communicated from said sense electrodes to said data collector using a wireless communication protocol.

105. The method according to claim 104, wherein said wireless communication protocol comprises using quasi electrostatic coupling to a conductive tissue of said patient.

106. The method according to claim 105, wherein said protocol employs said sense electrodes as an antenna.

107. The method according to claim 105, wherein said protocol employs one or more electrodes distinct from said sense electrodes as an antenna.

108. The method according to claim 96, wherein said physiological parameter corresponds to a blood flow velocity.

109. The method according to claim 96, further comprising performing a remedial action based on said physiological parameter.

110. The method according to claim 109, wherein said remedial action comprises administering a pharmaceutical agent to said patient.

111. The method according to claim 109, wherein said remedial action comprises administering an electrical stimulus to said patient.

112. The method according to claim 109, wherein said remedial action comprises alerting said patient to seek medical attention.

113. A kit comprising:

(1) an implantable fluid flow sensor comprising;

(a) a pair of sense electrodes; and

(b) a detection circuit configured to;

(i) detect a potential difference between said sense electrodes, the potential difference resulting from an applied magnetic field to flowing fluid, and

(ii) produce an output signal at an output node, the output signal correlating to the potential difference; and

(2) instructions for using said fluid flow sensor to determine a physiological parameter of a patient.