CARDIAC CATHETER EMPLOYING CONFORMAL ELECTRONICS FOR MAPPING

• US 20130274562A1
• Filed: 10/05/2012
• Published: 10/17/2013
• Est. Priority Date: 10/05/2011
• Status: Active Grant

• Current Assignee: Medidata Solutions Incorporated (Dassault Systemes SA)
• Original Assignee: MC10, Inc.
• Inventors: Ghaffari, Roozbeh, Lee, Stephen P., Elolampi, Brian
• Granted Patent: US 9,545,285 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 18/20 using laser
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/0022 Balloons
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00648 using more than one sensed parameter
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2018/0212 using an instrument inserted into a body lumen, e.g. catheter
• CPC Class Codes: A61B 2018/0237 with a thermoelectric element in the probe for cooling purposes
• CPC Class Codes: A61B 2018/0262 using a circulating cryogenic fluid
• CPC Class Codes: A61B 2562/0215 Silver or silver chloride containing
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/0261 Strain gauges
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/0036 including treatment, e.g., using an implantable medical device, ablating, ventilating
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• 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 5/02055 : Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/0215 : by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/02405 : Determining heart rate variability
• CPC Class Codes: A61B 5/036 : by means introduced into body tracts A61B5/032 and A61B5/035 take precedence
• CPC Class Codes: A61B 5/053 : Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0538 : invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/14539 : for measuring pH
• CPC Class Codes: A61B 5/14546 : for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1473 : invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/259 : using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/283 : Invasive
• CPC Class Codes: A61B 5/287 : Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/339 : Displays specially adapted therefor
• CPC Class Codes: A61B 5/361 : Detecting fibrillation
• CPC Class Codes: A61B 5/6833 : Adhesive patches
• CPC Class Codes: A61B 5/6853 : with a balloon
• CPC Class Codes: A61B 5/6885 : Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61M 2025/105 : having a balloon suitable for drug delivery, e.g. by using holes for delivery, drug coating or membranes
• CPC Class Codes: A61M 25/10 : Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00
• CPC Class Codes: A61N 7/00 : Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

An apparatus for medical diagnosis and/or treatment is provided. The apparatus includes a flexible substrate, an intermediate bus disposed on the flexible substrate, and a plurality of sensing elements disposed on the flexible substrate and coupled to the intermediate bus. The plurality of sensing elements and intermediate bus are disposed on the flexible substrate such that the sensing elements are disposed at areas of minimal strain of the flexible substrate.

Claims

1. An apparatus for medical diagnosis and/or treatment, the apparatus comprising:

a flexible substrate;

at least one intermediate bus disposed on the flexible substrate; and

a plurality of sensing elements disposed in a close-packed array proximate to an end of the at least one intermediate bus,

wherein each sensing element of the plurality of sensing elements is coupled to the at least one intermediate bus.

2. The apparatus of claim 1, wherein the sensing elements are disposed at areas of minimal bending and/or flexing of the flexible substrate.

3. The apparatus of claim 1, wherein the flexible substrate is an adhesive patch or a bandage.

4. The apparatus of claim 1, wherein a measurement of the plurality of sensing elements provides a measure of an amount of contact between the inflatable body and a surface.

5. The apparatus of claim 4, wherein the surface is a portion of a tissue, wherein a measurement from the plurality of sensing elements provides an indication of an arrhythmia condition of the tissue.

6. The apparatus of claim 4, wherein the surface is a portion of a tissue, wherein a measurement from the plurality of sensing elements provides an indication of an artial fibrillation or a ventricular fibrillation of the tissue.

7. The apparatus of claim 1, wherein the flexible substrate forms an inflatable body, and wherein a portion of the at least one intermediate bus is disposed about a distal region of the inflatable body.

8. The apparatus of claim 7, wherein the inflatable body is a disposed on a catheter, and wherein a measurement of the plurality of sensing elements provides a measure of an amount of contact between the inflatable body and a tissue.

9. The apparatus of claim 8, wherein the measurement of the plurality of sensing elements provides a mapping of the tissue.

10. The apparatus of claim 8, wherein the measurement of the plurality of sensing elements provides a spatial mapping and/or a temporal mapping of an arrhythmia.

11. An apparatus for medical diagnosis and/or treatment, the apparatus comprising:

a flexible substrate forming an inflatable body;

at least one intermediate bus, wherein a portion of the at least one intermediate bus is disposed about a distal region of the inflatable body; and

a plurality of sensing elements disposed on the flexible substrate proximate to the distal region of the inflatable body in an array, and

wherein at least one sensing element of the plurality of sensing elements is coupled to the at least one intermediate bus.

12. The apparatus of claim 11, wherein the at least one intermediate bus is electrically conductive.

13. The apparatus of claim 12, wherein portions of the at least one intermediate bus are formed from a non-conductive material.

14. The apparatus of claim 11, further comprising at least one coupling structure disposed about a distal region of the inflatable body, wherein a portion of the at least one intermediate bus is coupled to a portion of the at least one coupling bus.

15. The apparatus of claim 14, wherein the coupling structure is a non-conductive structure.

16. The apparatus of claim 11, wherein the plurality of sensing elements are disposed in an array at an area of minimal curvature of the inflatable body proximate to the distal region of the inflatable body.

17. The apparatus of claim 11, wherein each of the at least one intermediate bus electronically connects each sensing element of the plurality of sensing elements with an electrical source.

18. The apparatus of claim 11, wherein the plurality of sensing elements are disposed in an array in a quadrant of the distal region of the inflatable body.

19. The apparatus of claim 11, wherein the intermediate bus is a collection of serpentine buses, and wherein the serpentine buses electrically couple to the plurality of sensing elements.

20. The apparatus of claim 11, further comprising an encapsulation material disposed over substantially a portion of the intermediate bus and/or the plurality of sensing elements.

21. The apparatus of claim 20, wherein the encapsulation material comprises a polyurethane.

22. The apparatus of claim 11, wherein:

the at least one intermediate bus comprises a first intermediate bus and a second intermediate bus,

wherein the first intermediate bus couples to sensing elements of the plurality of sensing elements disposed in a first quadrant of the distal region of the inflatable body,

wherein the second intermediate bus couples to sensing elements of the plurality of sensing elements disposed in a second quadrant of the distal region of the inflatable body; and

wherein the first quadrant is disposed opposite to the second quadrant.

23. The apparatus of claim 22, further comprising:

a third intermediate bus and a fourth intermediate bus,

wherein the third intermediate bus couples to sensing elements of the plurality of sensing elements disposed in a third quadrant of the distal region of the inflatable body,

wherein the fourth intermediate bus couples to sensing elements of the plurality of sensing elements disposed in a fourth quadrant of the distal region of the inflatable body; and

wherein the third quadrant is disposed opposite to the fourth quadrant; and

wherein the third quadrant is oriented at substantially a 90°

angle relative to the first quadrant.

24. The apparatus of claim 22, wherein the inflatable body is disposed about a shaft, and wherein the shaft comprises a cryoablation device, a laser ablation device, a high intensity ultrasound, and/or a RF device.

25. The apparatus of claim 11, wherein the plurality of sensing elements comprise at least one of a pressure sensor and/or at least one impedance sensor.

26. The apparatus of claim 11, wherein one or more of the sensing elements of the plurality of sensing elements comprises contact sensors

27. The apparatus of claim 11, further comprising an encapsulation layer disposed over the plurality of sensing elements, wherein the encapsulation layer positions the sensing elements at a neutral mechanical plane.

28. The apparatus of claim 27, wherein the encapsulation layer comprises a polymer.

29. The apparatus of claim 11, wherein the inflatable body is disposed near a distal end of a catheter.

30. The apparatus of claim 29, wherein the catheter comprises a cryoablation device, a laser ablation device, a high intensity ultrasound, and/or a RF device

31. The apparatus of claim 11, wherein the inflatable body is a balloon.

32. The apparatus of claim 31, wherein the balloon is cylindrical, onion-shaped, cone-shaped, dog-bone-shaped, barrel-shaped.

33. The apparatus of claim 11, wherein the sensing elements are formed from a conductive material.

34. The apparatus of claim 11, wherein the intermediate bus is formed from a conductive material.

35. A method of fabricating an apparatus for medical diagnosis and/or treatment, the method comprising:

providing an electronic structure comprising;

a first intermediate bus; and

a plurality of sensing elements, wherein a first sensing element of the plurality of sensing elements is coupled to the first intermediate bus;

disposing a portion of the first intermediate bus at a first distal region of an inflatable body; and

disposing the first sensing element of the plurality of sensing elements about a portion of the inflatable body proximate to the first distal region.

36. The method of claim 35, wherein the plurality of sensing elements are disposed about the portion of the inflatable body proximate to the distal region such that the sensor elements are disposed at areas of minimal curvature of the inflatable body.

37. The method of claim 35, further comprising extracting the electronic structure from a carrier substrate prior to disposing the electronic structure about the inflatable body.

38. The method of claim 37, wherein the disposing the electronic structure about the inflatable body comprises applying the first intermediate bus and/or the plurality of sensing elements using a dissolvable tape.

39. The method of claim 35, wherein the electronic structure further comprises a coupling structure, wherein the first intermediate bus is coupled to a portion of the coupling structure, and wherein the disposing the electronic structure about the inflatable body comprises disposing the coupling structure about the inflatable body;

and aligning the plurality of sensing elements at the distal region of the inflatable body.

40. The method of claim 35, wherein the electronic structure is fabricated using a CMOS process.

41. The method of claim 35, wherein the electronic structure further comprises a second intermediate bus, wherein a second sensing element of the plurality of sensing elements is coupled to the second intermediate bus,

42. The method of claim 41, further comprising disposing a portion of the second intermediate bus at a second distal region of the inflatable body different from the first region;

and

disposing the second sensing element of the plurality of sensing elements about a portion of the inflatable body proximate to the second distal region.

43. The method of claim 42, further comprising coupling the first intermediate bus and the second intermediate bus to a signal processor, wherein the electronic structure is configured to transmit one or more multiplexed signals to the at least one signal processor via the first intermediate bus and the second intermediate bus.

44. A method of performing a medical diagnosis and/or treatment on a tissue, the method comprising:

disposing in proximity to the tissue an apparatus comprising;

a flexible substrate forming an inflatable body;

at least one intermediate bus, wherein a portion of the at least one intermediate bus is disposed at a distal region of the inflatable body; and

a plurality of sensing elements disposed on the flexible substrate proximate to the distal region of the inflatable body,

wherein at least one sensing element of the plurality of sensing elements is coupled to the at least one intermediate bus; and

recording a measurement of at least one sensing element of the plurality of sensing elements, wherein the measurement provides an indication of a state of a portion of the tissue.

45. The method of claim 44, wherein the measurement provides an indication of a disease state of the portion of the tissue.

46. The method of claim 44, wherein the measurement provides an indication of a contact state of the portion of the tissue with the at least one sensing element of the plurality of sensing elements.

47. The method of claim 44, wherein the plurality of sensing elements are disposed in an array at areas of minimal curvature of the inflatable body proximate to the distal region of the inflatable body.

48. A system for mapping contact with a surface, the system comprising:

an inflatable body having a distal portion;

a plurality of sensing elements disposed on the inflatable body proximate to the distal portion;

at least one intermediate bus, wherein at least one sensing element of the plurality of sensing elements is coupled to the at least one intermediate bus; and

an electronic display electrically coupled to the plurality of sensing elements, the electronic display providing a visual representation of the spatial orientation of the plurality of sensing elements on the inflatable body, the electronic display changing a visual attribute of an electrode in the plurality of sensing elements in response to a change in an electrical signal produced by the electrode, and the change in the electrical signal identifying a contact condition of the electrode with respect to the surface.

49. The apparatus of claim 48, wherein the visual attribute is a binary representation

50. The apparatus of claim 48, wherein the visual attribute is a quantitative representation.

51. An apparatus for generating one or more multiplexed signals, the apparatus comprising:

a flexible substrate; and

a plurality of active electrical circuits coupled to the flexible substrate, each active electrical circuit in the plurality of active electrical circuits coupled to at least one adjacent active electrical circuit in the plurality of active electrical circuits via at least one conductive flexible interconnection, the plurality of active electrical circuits configured to transmit one or more multiplexed signals to at least one signal processor.

52. The apparatus of claim 51, wherein one or more of the active electrical circuits in the plurality of active electrical circuits includes at least one electrode.

53. The apparatus of claim 51, wherein one or more of the active electrical circuits in the plurality of active electrical circuits includes at least one multiplexing transistor.

54. The apparatus of claim 51, one or more of the active electrical circuits in the plurality of active electrical circuits includes at least one amplifier.

55. The apparatus of claim 51, wherein one or more of the active electrical circuits in the plurality of active electrical circuits includes at least one current mirror.

56. The apparatus of claim 51, wherein the current mirror is switchable between an off state and an on state.

57. The apparatus of claim 51, wherein one or more of the active electrical circuits in the plurality of active electrical circuits includes at least one current limiting resistor.

58. The apparatus of claim 51, wherein the plurality of active electrical circuits are positioned in a plurality of arrays on the flexible substrate.

59. The apparatus of claim 58, wherein the at least one signal processor is configured to receive a multiplexed signal from each active circuit.

60. The apparatus of claim 51, wherein the substrate is stretchable.

61. The apparatus of claim 51, wherein the substrate is elastic.

62. The apparatus of claim 51, wherein the conductive flexible interconnection is buckled.

63. The apparatus of claim 51, wherein the conductive flexible interconnection has a serpentine geometric configuration.

64. The apparatus of claim 51, wherein the active electrical circuits includes one or more components selected from the group consisting of:

a transistor, a resistor, a capacitor, an inductor, and a diode.

65. The apparatus of claim 51, wherein at least one circuit in the plurality of active electrical circuits include at least one of, temperature sensor, a pressure sensor, a contact sensor, a conductivity sensor, a strain gauge, a complementary metal-oxide-semiconductor, metal oxide semiconductor field effect transistor, a light emitting diode, an electrode, a pH sensor, a chemical sensor, a biological sensor, and a calcium sensor.

66. The apparatus of claim 51, wherein the plurality of active circuits are positioned in one or more arrays on the flexible substrate.

67. The apparatus of claim 51, wherein the at least one processor is configured to construct a map of at least one physiological parameter by associating a portion of the multiplexed signal with one or more originating active electrical circuits in the plurality of active electrical circuits.

68. The apparatus of claim 51, wherein the substrate has an active electrical circuit density of at least 64 circuits per cm².

69. The apparatus of claim 51, wherein the substrate has an active electrical circuit density ranging from 200 to 500 circuits per cm².

70. A method of generating one or more multiplexed signals, the method comprising:

positioning a flexible substrate adjacent to an internal body surface, the flexible substrate having a plurality of active electrical circuits coupled thereto, each active electrical circuit in the plurality of active electrical circuits coupled to at least one adjacent active electrical circuit in the plurality of active electrical circuits via at least one conductive flexible interconnection;

causing the substrate to move from a first configuration to a second configuration;

transmitting one or more multiplexed signals from the plurality of active electrical circuits to at least one signal processor; and

characterizing the at least one physiological parameter based on the multiplexed signal received by the signal processor.

71. An apparatus for readout of one or more multiplexed signals, the apparatus comprising:

a flexible substrate forming an inflatable body; and

a plurality of active electrical circuits disposed on the flexible substrate, the plurality of active electrical circuits configured to transmit one or more multiplexed signals to at least one signal processor, at least one active electrical circuit of the plurality of active electrical circuits comprising;

at least one electrode; and

at least one source-follower amplifier coupled to the at least one electrode;

wherein the plurality of active electrical circuits are disposed in a distributed arrangement on the substrate such that the apparatus is conformable to a contour of a surface to be measured.

72. The apparatus of claim 71, wherein the plurality of active electrical circuits are disposed at areas of minimal curvature of the inflatable body in the distributed arrangement.

73. The apparatus of claim 71, wherein each active electrical circuit of the plurality of active electrical circuits is coupled to at least one adjacent active electrical circuit of the plurality of active electrical circuits via at least one conductive flexible interconnection.

74. The apparatus of claim 71, further comprising at least one conductive intermediate bus, wherein the at least one active electrical circuit of the plurality of active electrical circuits is coupled to the at least one conductive intermediate bus, and each active electrical circuit of the plurality of active electrical includes at least one sensing element.

75. The apparatus of claim 74, wherein the plurality of active electrical circuits is configured to transmit one or more multiplexed signals to the at least one signal processor via the at least one conductive intermediate bus.

76. The apparatus of claim 71, wherein the at least one active electrical circuit of the plurality of active electrical circuits further comprises at least one pass-through switch, and wherein the at least one source-follower amplifier is coupled to the at least one pass-through switch.

77. The apparatus of claim 71, wherein each of the active electrical circuit of the plurality of active electrical circuits comprises:

at least one electrode;

at least one source-follower amplifier coupled to the at least one electrode; and

at least one pass-through switch coupled to the at least one source-follower amplifier.

78. The apparatus of claim 77, wherein the at least one source-follower amplifier is an input transistor having a drain coupled to ground, and wherein the pass-through switch is a pass-through transistor coupled to the input transistor.

79. The apparatus of claim 78, wherein a source of the input transistor is coupled to a drain of the pass-through transistor.

80. The apparatus of claim 79, wherein a source of the pass-through transistor is coupled to the drain of that respective pass-through transistor, and wherein the respective at least one electrode of each active electrical circuit is coupled to a gate of the respective input transistor.

81. The apparatus of claim 79, wherein the input transistor is a NMOS transistor.

82. The apparatus of claim 79, wherein the pass-through transistor is a NMOS transistor.

83. The apparatus of claim 79, wherein the plurality of active electrical circuits are read in a row-column arrangement, and wherein each row-column element of the row-column arrangement corresponds to at least one active electrical circuit of the plurality of active electrical circuits.

84. The apparatus of claim 83, wherein the source of the pass-through transistor of each respective active electrical circuits is coupled to a column output of each respective row-column element.

85. The apparatus of claim 84, wherein all columns of the row-column arrangement are read substantially simultaneously, and wherein a single row of the row-column arrangement is active when the columns of the row-column arrangement are read.

86. The apparatus of claim 84, wherein the source of the pass-through transistor of at least two active electrical circuits are coupled to the column output of each respective row-column element.

87. The apparatus of claim 84, wherein each row input of the row-column arrangement is coupled to a gate of a pass-through transistor of each active electrical circuit of the plurality of active electrical circuits.

88. The apparatus of claim 84, wherein the voltage at the gate of the input transistor determines the voltage at the source of the input transistor.

89. A method for readout of one or more multiplexed signals, the method comprising:

disposing an apparatus proximate to a surface, the apparatus comprising;

a plurality of active electrical circuits disposed in a distributed arrangement on a flexible substrate forming an inflatable body, the plurality of active electrical circuits configured to transmit one or more multiplexed signals to at least one signal processor, wherein at least one active electrical circuit of the plurality of active electrical circuits comprises;

an electrode;

a source-follower amplifier coupled to the electrode; and

a pass-through switch coupled to the source-follower amplifier, a row control switch and a column output, wherein a voltage applied to the row control switch activates the pass-through switch such that a signal from the electrode is transmitted to the column output;

applying a voltage to the row control switch; and

reading an output at the column output thereby providing the one or more multiplexed signals.

90. The method of claim 89, wherein the plurality of active electrical circuits is are disposed proximate to the electrode in the distributed arrangement.

91. The method of claim 89, wherein each active electrical circuit of the plurality of active electrical circuits is coupled to at least one adjacent active electrical circuit of the plurality of active electrical circuits via at least one conductive flexible interconnection.

92. The method of claim 91, further comprising transmitting the one or more multiplexed signals from the plurality of active electrical circuits to the at least one signal processor via the at least one conductive flexible interconnection.

93. The method of claim 89, wherein the apparatus further comprises at least one conductive intermediate bus, wherein the at least one active electrical circuit of the plurality of active electrical is coupled to the at least one conductive intermediate bus.

94. The method of claim 93, further comprising transmitting the one or more multiplexed signals from the plurality of active electrical circuits to the at least one signal processor via the at least one conductive intermediate bus.

95. The method of claim 89, wherein the electrode is coupled to a gate of the source-follower amplifier.

96. The method of claim 95, wherein a source of the at least one source-follower amplifier is coupled to a drain of the at least one pass-through switch, wherein a gate of the pass-through switch is coupled to the row control switch, and wherein a source of the pass-through switch is coupled to the column output.

97. The method of claim 89, wherein the drain of the source-follower amplifier is biased to a ground potential.

98. The method of claim 89, wherein the at least one active electrical circuits comprises two active electrical circuits, wherein each of the two active electrical circuits is coupled to a respective row control switch, wherein the two active electrical circuits are coupled to a common column output, and wherein the voltage is applied to one of the row control switches during the reading of the output from the common column output.

99. An apparatus for readout of one or more multiplexed signals, the apparatus comprising:

a flexible substrate; and

a plurality of active electrical circuits disposed on the substrate in a distributed arrangement, the plurality of active electrical circuits configured to transmit one or more multiplexed signals to at least one signal processor, at least one active electrical circuit of the plurality of active electrical circuits comprising;

at least one electrode; and

at least one differential pair amplifier coupled to the at least one electrode;

wherein the plurality of active electrical circuits are disposed in a distributed arrangement on the substrate such that the apparatus is conformable to a contour of a surface to be measured.

100. The apparatus of claim 99, wherein the flexible substrate is a portion of an inflatable body, and wherein the plurality of active electrical circuits are disposed at areas of minimal curvature of the inflatable body in the distributed arrangement.

101. The apparatus of claim 99, wherein each active electrical circuit of the plurality of active electrical circuits is coupled to at least one adjacent active electrical circuit of the plurality of active electrical circuits via at least one conductive flexible interconnection.

102. The apparatus of claim 99, further comprising at least one conductive intermediate bus, wherein the at least one active electrical circuit of the plurality of active electrical is coupled to the at least one conductive intermediate bus.

103. The apparatus of claim 102, wherein the plurality of active electrical circuits is configured to transmit one or more multiplexed signals to the at least one signal processor via the at least one conductive intermediate bus.

104. The apparatus of claim 99, wherein the at least one active electrical circuit of the plurality of active electrical circuits further comprises a tail, and wherein the at least one differential pair amplifier is coupled to the tail.

105. The apparatus of claim 99, wherein each of the active electrical circuit of the plurality of active electrical circuits comprises:

at least one electrode; and

at least one differential pair amplifier coupled to the at least one electrode.

106. The apparatus of claim 105, wherein each of the at least one differential pair amplifier comprises a pair of transistors whose sources are connected in a common connection to provide a common source.

107. The apparatus of claim 106, wherein the pair of transistors are PMOS transistors.

108. The apparatus of claim 106, wherein each of the transistors is connected in series with a current limiting resistor.

109. The apparatus of claim 106, wherein each of the at least one differential pair amplifier is coupled to a tail.

110. The apparatus of claim 109, wherein the tail is a transistor, and wherein the common source of the at least one differential pair amplifier is coupled to a drain of the tail.

111. The apparatus of claim 109, wherein the gate of the tail is driven by a current-mirror.

112. The apparatus of claim 106, wherein the at least one electrode is coupled to a gate of a transistor of the pair of transistors.

113. The apparatus of claim 106, wherein the plurality of active electrical circuits are read in a row-column arrangement, wherein each row-column element of the row-column arrangement corresponds to at least one active electrical circuit of the plurality of active electrical circuits, and wherein a drain of a first transistor of the pair of transistors of each respective active electrical circuit is coupled to a column output of each respective row-column element.

114. The apparatus of claim 113, wherein a second transistor of the pair of transistors of each respective active electrical circuit is coupled to a load resistor.

115. The apparatus of claim 113, wherein all columns of the row-column arrangement are read substantially simultaneously, and wherein a single row of the row-column arrangement is active when the columns of the row-column arrangement are read.

116. The apparatus of claim 113, wherein the drain of the first transistor of the pair of transistors of at least two active electrical circuits are coupled to the column output of each respective row-column element.

117. The apparatus of claim 106, wherein each of the at least one differential pair amplifier of each active electrical circuit is coupled to a tail, and wherein each row input of the row-column arrangement is coupled to a gate of a tail of each active electrical circuit of the plurality of active electrical circuits.

118. The apparatus of claim 117, wherein each row input of the row-column arrangement is coupled to a gate of a tail of each active electrical circuit of the plurality of active electrical circuits.

119. The apparatus of claim 99, wherein the at least one active electrical circuit of the plurality of active electrical circuits comprises:

two electrodes, and

a differential pair amplifier, wherein the two electrodes are coupled to the differential pair amplifier.

120. The apparatus of claim 119, wherein the differential pair amplifier comprises a pair of transistors whose sources are connected in a common connection to provide a common source.

121. The apparatus of claim 120, wherein each electrode is coupled to a gate of each transistor of the pair of transistors.

122. The apparatus of claim 121, wherein a read-out of the at least one active electrical circuit is based on a differential of signals from the two electrodes.

123. A method for readout of one or more multiplexed signals, the method comprising:

disposing an apparatus proximate to a surface, the apparatus comprising;

a plurality of active electrical circuits disposed on a flexible substrate in a distributed arrangement, the plurality of active electrical circuits configured to transmit one or more multiplexed signals to at least one signal processor, wherein at least one active electrical circuit of the plurality of active electrical circuits comprises;

an electrode;

a differential pair amplifier coupled to the electrode; and

a tail coupled to the differential pair amplifier, wherein the tail is coupled to a row control switch, wherein the differential pair amplifier is coupled to a column output, and wherein activating the row control switch activates the differential pair amplifier such that a signal from the electrode is transmitted to the column output;

applying a voltage to the row control switch; and

reading an output at the column output thereby providing the one or more multiplexed signals.

124. The method of claim 123, wherein the plurality of active electrical circuits is coupled to a flexible substrate forming an inflatable body.

125. The method of claim 123, wherein each active electrical circuit of the plurality of active electrical circuits is coupled to at least one adjacent active electrical circuit of the plurality of active electrical circuits via at least one conductive flexible interconnection.

126. The method of claim 125, further comprising transmitting the one or more multiplexed signals from the plurality of active electrical circuits to the at least one signal processor via the at least one conductive flexible interconnection.

127. The method of claim 123, wherein the apparatus further comprises at least one conductive intermediate bus, wherein the at least one active electrical circuit of the plurality of active electrical is coupled to the at least one conductive intermediate bus.

128. The method of claim 127, further comprising transmitting the one or more multiplexed signals from the plurality of active electrical circuits to the at least one signal processor via the at least one conductive intermediate bus.

129. The method of claim 123, wherein the electrode is coupled to a first gate of the differential pair amplifier.

130. The method of claim 129, wherein the apparatus further comprises a second electrode, and wherein a second gate of the differential pair amplifier is coupled to the second electrode.

131. The method of claim 129, wherein the apparatus further comprises a second electrode, and wherein a second gate of the differential pair amplifier is biased to a ground potential.

132. The method of claim 123, wherein the tail is coupled to the row control switch via a current-mirror, and wherein activating the row control switch biases the current-mirror, thereby activating the differential pair amplifier.

133. The method of claim 123, wherein the at least one active electrical circuits comprises two active electrical circuits, wherein each of the two active electrical circuits is coupled to a respective row control switch, wherein the two active electrical circuits are coupled to a common column output, and wherein one of the row control switches is activated during the reading of the output from the common column output.