Biocapacitive sensor

Abstract

The present disclosure provides apparatuses and methods for measuring bio-capacitance of a tissue. The apparatuses include a sensor including two electrodes, a movable element coupled to the sensor, and a switch disposed between the movable element and a fixed element, wherein the switch electrically closes when a gap between the movable element and the fixed element is less than or equal to a predetermined value. When the switch is closed, the device measures bio-capacitance between the two electrodes.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to U.S. Provisional Application 63 / 004,822, filed April 3, 2020, which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure provides apparatus and methods for non-invasive assessment of biocapacitance in living tissue. Background Technology

[0004] Current methods for measuring biocapacitance require manual control of the pressure applied by the sensing device, as the measurement varies depending on the applied pressure. Methods that automate measurements at an appropriate applied pressure without requiring user intervention would improve measurement repeatability. Summary of the Invention

[0005] On one hand, this disclosure provides and includes an apparatus for measuring the biocapacitance of tissue, the apparatus comprising: a sensor including two electrodes; a movable element coupled to the sensor; a switch disposed between the movable element and a fixed element and configured to electrically close when the gap between the movable element and the fixed element is less than or equal to a predetermined value; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; and a processor coupled to the switch and the device and configured to receive the measurement from the device when the switch is electrically closed.

[0006] On one hand, the electrodes are configured such that when the sensor is positioned near the tissue, the electric field between the electrodes penetrates into the tissue.

[0007] On one hand, the device is configured to repeatedly measure the capacitance between the two electrodes at predetermined intervals.

[0008] On one hand, the sensor further includes an insulating cover layer coupled to the electrode, wherein the insulating cover layer is configured to prevent conductive contact between the electrode and the tissue when the sensor is positioned close to the tissue.

[0009] On one hand, the measurement includes a comparison of the capacitance between the electrodes with the capacitance of a reference capacitor.

[0010] On one hand, the comparison includes using a Σ-Δ method that compares the capacitance between the electrodes with the capacitance of the reference capacitor.

[0011] On one hand, the device further includes a visual indicator coupled to the processor, wherein the processor is further configured to activate the visual indicator when the switch is closed.

[0012] On one hand, the movable element is configured to move relative to the fixed element along a translation axis, and the gap is disposed on the translation axis.

[0013] On one hand, the device further includes a spring positioned between the movable element and the fixed element, and configured to provide a force that increases monotonically along the translation axis to separate the movable element from the fixed element.

[0014] On one hand, the movable element is further configured to allow rotation about at least one of a first rotation axis perpendicular to the translation axis and a second rotation axis perpendicular to both the translation axis and the first rotation axis.

[0015] On one hand, the processor is further configured to electrically disconnect the switch after receiving a first measurement when the switch is first closed, and before a second measurement can be received.

[0016] On one hand, this disclosure provides and includes an apparatus for measuring the biocapacitance of tissue, the apparatus comprising: a sensor including two electrodes; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; a barcode scanning engine configured to optically scan a machine-readable image and determine a first alphanumeric string encoded in the machine-readable image; and a processor coupled to the device and the engine and configured to receive the measurement from the device and receive the first alphanumeric string from the engine.

[0017] On one hand, the processor is further configured to receive a plurality of consecutive alphanumeric strings, and associate each of the consecutive alphanumeric strings with one of a patient, user, observation, intervention, consumable element, durable element, location, and time.

[0018] On one hand, the processor is further configured to associate the patient's first alphanumeric string with the consecutive alphanumeric strings.

[0019] On the one hand, the processor is further configured to transmit the associated alphanumeric string to the data system.

[0020] On one hand, this disclosure provides and includes a method for measuring the biocapacitance of tissue, the method comprising positioning a sensor including a first electrode and a second electrode against a patient’s skin above the tissue, measuring the capacitance between the two electrodes, optically scanning a primary machine-readable image associated with the patient, determining a primary alphanumeric string encoded in the primary machine-readable image, and associating the capacitance with the primary alphanumeric string.

[0021] On one hand, the method further includes optically scanning one or more secondary machine-readable images associated with one of a user, observation, intervention, consumable element, durable element, location, and time; determining a secondary alphanumeric string encoded in each of the one or more secondary machine-readable images; and associating the secondary alphanumeric string with the primary alphanumeric string.

[0022] On one hand, the method further includes transmitting the primary and secondary alphanumeric strings to a data system. Attached Figure Description

[0023] This document describes aspects of the present disclosure by way of example only, with reference to the accompanying drawings. Referring now to the drawings in detail, it should be emphasized that the details shown are by way of example and are used for illustrative discussion of aspects of the present disclosure. In this respect, the description and drawings, considered individually and together, will make it apparent to those skilled in the art how aspects of the present disclosure can be practiced.

[0024] Figure 1A It is a plan view of the ring sensor according to this disclosure.

[0025] Figure 1B This is a plan view of another aspect of the sensor according to this disclosure.

[0026] Figure 1C Based on this disclosure Figure 1A A cross-sectional view of the sensor.

[0027] Figure 1D Depicting according to this disclosure Figure 1A An illustrative example of the electric field between the two electrodes of a sensor.

[0028] Figure 2 A classic model of a capacitor is depicted.

[0029] Figure 3A One aspect of a biocapacitance scanner according to this disclosure is described.

[0030] Figure 3B-3C Construction details of the biocapacitance scanner according to this disclosure are depicted.

[0031] Figures 4A-4C A state sequence of a portion of the scanner according to Figure 3 of this disclosure is depicted.

[0032] Figure 5 A portion of an alternative aspect of the scanner according to Figure 3 of this disclosure is depicted.

[0033] Figure 6 One aspect of a visual indicator according to this disclosure is depicted.

[0034] Figure 7A Another aspect of the biocapacitance scanner according to this disclosure is depicted.

[0035] Figure 7B An exploded view of the components of the biocapacitance scanner according to this disclosure is depicted.

[0036] Figures 8A-8D A sequence of states of a device configured to perform a Σ-Δ method for measuring capacitance according to this disclosure is described.

[0037] Figure 9A A hardware block diagram for measuring the capacitance of a sensor according to this disclosure is depicted.

[0038] Figure 9B A diagram depicts a system for measuring, storing, transmitting, and accessing measurement data according to this disclosure.

[0039] Figure 10 The workflow according to this disclosure, including scanning primary and secondary barcodes, is described. Detailed Implementation

[0040] This disclosure provides an apparatus and method for measuring the biocapacitance of tissue. In one aspect, this disclosure provides and includes an apparatus for measuring the biocapacitance of tissue, the apparatus comprising: a sensor including two electrodes; a movable element coupled to the sensor; a switch disposed between the movable element and a fixed element and configured to electrically close when the gap between the movable element and the fixed element is less than or equal to a predetermined value; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; and a processor coupled to the switch and the device and configured to receive the measurement from the device when the switch is electrically closed.

[0041] On one hand, this disclosure provides and includes an apparatus for measuring the biocapacitance of tissue, the apparatus comprising: a sensor including two electrodes; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; a barcode scanning engine configured to optically scan a machine-readable image and determine a first alphanumeric string encoded in the machine-readable image; and a processor coupled to the device and the engine and configured to receive the measurement from the device and receive the first alphanumeric string from the engine.

[0042] On one hand, this disclosure provides and includes a method for measuring the biocapacitance of tissue, the method comprising positioning a sensor including a first electrode and a second electrode against a patient’s skin above the tissue, measuring the capacitance between the two electrodes, optically scanning a primary machine-readable image associated with the patient, determining a primary alphanumeric string encoded in the primary machine-readable image, and associating the capacitance with the primary alphanumeric string.

[0043] This description is not intended to be a detailed list of all different ways in which this disclosure may be implemented or all features that may be added to this disclosure. For example, a feature shown with respect to one aspect may be incorporated into other aspects, and a feature shown with respect to a particular aspect may be removed from said aspect. Therefore, this disclosure contemplates that in some aspects of this disclosure, any feature or combination of features set forth herein may be excluded or omitted. Furthermore, numerous variations and additions to the various aspects suggested herein will be apparent to those skilled in the art, and such variations and additions do not depart from this disclosure. In other instances, well-known structures, interfaces, and processes have not been shown in detail so as not to unnecessarily obscure the invention. Nothing in this specification is intended to be construed as denying any part of the full scope of the invention. Therefore, the following description is intended to illustrate certain aspects of this disclosure, rather than to exhaustively specify all permutations, combinations, and variations thereof.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. The terminology used herein in describing this disclosure is for the purpose of describing particular aspects or embodiments only and is not intended to be limiting of this disclosure.

[0045] All publications, patent applications, patents, and other references cited herein are incorporated in their entirety for the purpose of teaching in relation to the sentences and / or paragraphs in which they are referenced. References to techniques used herein are intended to refer to techniques commonly understood in the art, including variations of those techniques or substitutions for equivalent techniques that would be obvious to a person skilled in the art.

[0046] U.S. Patent Application Serial No. 14 / 827,375 discloses a device that uses radio frequency (RF) energy to perform similar functions. Figure 1A The sensor 90 shown is a bipolar sensor used to measure subepidermal capacitance. Subepidermal capacitance is related to the moisture content of the target area on the patient's skin. Application '375 also discloses arrays of these bipolar sensors of various sizes.

[0047] U.S. Patent Application Serial No. 15 / 134,110 discloses a device for measuring subepidermal water (SEM), which transmits and receives RF signals at a frequency of 32 kHz via a single coaxial sensor and generates a bioimpedance signal, which is then converted to generate SEM values.

[0048] Both U.S. patent application serial numbers 14 / 827,375 and 15 / 134,110 are incorporated herein by reference in their entirety.

[0049] Unless the context otherwise indicates, it is expressly intended that the various features of this disclosure described herein may be used in any combination. Furthermore, this disclosure also contemplates that in some aspects of this disclosure, any feature or combination of features set forth herein may be excluded or omitted.

[0050] The methods disclosed herein include and encompass one or more steps or actions for implementing the described methods. The method steps and / or actions may be interchanged without departing from the scope of the invention. In other words, unless proper operation requires a specific order of steps or actions, the order and / or use of particular steps and / or actions may be modified without departing from the scope of the invention.

[0051] As used in the specification and appended claims of this disclosure, unless the context clearly indicates otherwise, the singular forms “a”, “an” and “the” are intended to include the plural forms as well.

[0052] As used in this article, “and / or” and “or” refer to and cover any and all possible combinations of one or more of the related listed items.

[0053] When referring to measurable values ​​such as length, time interval or period, frequency or SEM value, the terms “about” and “approximately” as used herein mean to cover a variation of ±20%, ±10%, ±5%, ±1%, ±0.5% or even ±0.1% of the specified amount.

[0054] As used herein, phrases such as “between X and Y” and “between approximately X and Y” should be interpreted as including both X and Y. As used herein, phrases such as “between approximately X and Y” mean “between approximately X and approximately Y” and phrases such as “from approximately X to Y” mean “from approximately X to approximately Y”.

[0055] As used herein, the term "subepidermal water" or "SEM" refers to the level of water contained in the tissue beneath the epidermis. Increased tissue fluid and localized edema may result from sustained tissue stress, including but not limited to the presence of apoptosis, necrosis, and inflammatory processes, as well as other changes due to vascular leakage and alteration of the underlying structure of damaged tissue.

[0056] As used herein, the term “tissue biocapacitance” refers to a biophysical marker used to detect initial tissue damage based on an increase in the level of fluid accumulation in the interstitial space.

[0057] As used herein, a “system” can be a collection of devices that are physically coupled or that are wired or wirelessly connected to each other.

[0058] As used in this article, "patient" can be a human or animal subject.

[0059] As used in this article, “healthy” can describe tissues that do not exhibit symptoms of damage to the cell wall or blood vessels, where the presence of increased extracellular fluid (ECF) is an indicator of such damage.

[0060] As used herein, a "switch" refers to a device that selectively provides an electrical connection between two elements or contacts. On the one hand, "closing" or deforming a portion of the switch creates an electrical connection between the two contacts, thereby closing the circuit, and "opening" or reversing the switch to its original form disconnects the electrical connection, thereby opening the circuit. On the other hand, applied pressure creates an electrical connection and the removal of force disconnects the connection.

[0061] As used in this article, “tissue” refers to a part of the body of a living person or animal. Tissue can comprise one or more layers of internal structures such as veins, arteries, capillaries, lymphatic vessels, and nerves, including the outermost stratum corneum, subepidermal layer, epidermis, and deeper layers of muscle, fat, and bone.

[0062] As used in this article, “biocapacitance” refers to the capacitance of a sensor whose active field is projected into the tissue.

[0063] As used in this article, a "spring" refers to a component with force-deformation characteristics, wherein an applied force produces deformation and / or the deformation produces restoring force.

[0064] As used herein, “insulation” and similar terms refer to a component characteristic that prevents significant electrical conductivity from passing through the component.

[0065] As used herein, a “machine-readable image” refers to a pattern containing coded information that can be observed by a machine and autonomously converted into information, such as an alphanumeric string. On one hand, a machine can project a beam of light and capture a portion of the reflected light. On the other hand, a machine can capture a 2D record of an image and process the image to extract the coded information. Furthermore, a “machine-readable image” can be a radio frequency sensitive device, such as a radio frequency identification (RFID) tag, whether passive or active.

[0066] As used in this article, an "alphanumeric string" refers to a sequence of characters that can contain uppercase or lowercase letters of any language and number. Alphanumeric strings may also be encoded in numeric form, such as a string of 0s and 1s that are uniquely associated with an alphanumeric string.

[0067] As used herein, "optical" refers, on the one hand, to the range of radiation wavelengths in the "visible" spectrum from approximately 380 nanometers to 740 nanometers (nm). On the other hand, this range may include a portion of the infrared spectrum above approximately 740 nm. On the other hand, this range may include a portion of the ultraviolet spectrum below approximately 380 nm. Furthermore, radio frequency systems can be replaced by equivalents of optical systems.

[0068] As used herein, a “data system” means a system that includes one or more of data processing capabilities, data transfer capabilities, and / or data storage capabilities. This data system may be directly coupled to a first processor or may be coupled to a second processor, which is communicatively coupled to the first processor. Storage elements may utilize any available volatile or non-volatile technology, including, but not limited to, solid-state drives (SSDs), spinning hard disk drives, and flash memory.

[0069] Figure 1A This is a plan view of one aspect of the sensor 90 according to the present disclosure. The ring sensor 90 includes a first electrode 110 embodied as a circular pad and a second electrode 120 embodied as a ring surrounding the electrode 110. Figure 1A It is axially symmetric, therefore it is insensitive to diagonal rotation.

[0070] Figure 1B This is a plan view of another aspect of the sensor 91 according to the present disclosure. In this respect, the two electrodes 111 and 121 are configured with a plurality of interleaved fingers.

[0071] Figure 1C Based on this disclosure Figure 1AA cross-sectional view of the sensor 90. In this respect, electrodes 110 and 120 are disposed on a common surface of the substrate 100 and are therefore coplanar with each other. On one hand, the electrodes may be disposed on different layers or non-planar surfaces of the substrate 100. On the other hand, an insulating cover layer 130 may be disposed on the electrodes 110 and 120, such as... Figure 1C As shown. When the sensor 90 is positioned against the skin, the insulating cover 130 prevents conductive contact between the electrodes 110, 120 and the skin. On the one hand, when the sensor 90 is positioned against the skin, one or more of the electrodes 110 and 120 are exposed and in conductive contact with the skin. On the other hand, multiple electrodes can be provided on the substrate 100. Figure 1C (not shown in the image), and the sensor 90 is formed by measuring the circuit ( Figure 1C (Not shown) is selectively connected to a first electrode and a second electrode from multiple electrodes for control.

[0072] Figure 1D Depicting according to this disclosure Figure 1A An illustrative example of the electric field 140 between the two electrodes 110 and 120 of the sensor 90. Electrodes 110 and 120 are positioned against the skin 60 of the patient tissue 50. For clarity, Figure 1D The cover layer 130 is omitted, and the cover layer may be disposed between the electrodes 110, 120 and the skin 60. The field 140 has an effective depth 150 below the skin 60.

[0073] Without any theoretical constraints, the capacitance measured between electrodes 110 and 120 depends in part on the dielectric constant of the tissue 50 within the effective field volume of field 140. Since the dielectric constant of water is approximately 81, while that of dry tissue is approximately 4, a small increase in the amount of water within the tissue (also known as subepidermal water) may result in an increase in the capacitance measured by sensor 90.

[0074] Figure 2 A classic model of a capacitor 200 according to this disclosure is depicted. The capacitor 200 includes a first planar electrode 210 and a second planar electrode 220 of the same size placed parallel to the electrode 210 at a distance "d". The space between electrodes 210 and 220 is filled with a capacitor having a relative permittivity ε. r The material is homogeneous, and the charges on electrodes 210 and 220 are shown as "-" and "+" signs, respectively. The science of capacitors is well known to those skilled in the art and can be found in standard electrical engineering references.

[0075] Capacitor 200 can hold charge Q. The voltage difference V between the two electrodes 210 and 220 caused by charge Q depends on the relative permittivity ε of the materials between the electrodes.r The capacitance C of capacitor 200 can be determined by measuring the charge Q supplied to capacitor 200 and the voltage difference V across electrodes 210 and 220 using the equation C = Q / V.

[0076] Figure 3A One aspect of the biocapacitive scanner 300 according to this disclosure is depicted. Sensor 310 is mounted on the "nose" 325 of the body 320.

[0077] Figure 3B Construction details of a biocapacitive scanner 300 according to this disclosure are depicted. The sensor 300, including a substrate and electrodes, is fixedly coupled to a carrier 330 including a top 332 and an axis 334. The axis 334 passes through a guide 350. On one hand, the axis 334 is movable relative to the guide 350 along an axis 336. On the other hand, the top 332 is movable relative to the axis 334 around one or more intersecting axes perpendicular to the axis 336. Figure 3B (Not shown in the image) Rotation. The printed circuit board assembly (PCBA) 340 includes a substrate 344 disposed below a carrier 330. On one hand, the substrate 344 is generally perpendicular to axis 336. On another hand, a switch 342 is coupled to the substrate 344 and disposed directly below axis 334. On one hand, the switch 342 is a dome switch that can collapse when a force greater than or equal to a predetermined value is applied, thereby electrically closing the circuit, wherein the direction of the force is generally perpendicular to the substrate 344. On one hand, the switch 342 is configured to electrically close the circuit when the force between the sensor 310 and the patient's skin is greater than a predetermined value. On one hand, the switch 342 is configured to electrically close the circuit when the gap between a movable element (e.g., carrier 330) and a fixed element (e.g., guide 350) is less than or equal to a determined value.

[0078] On the one hand, switch 342 is coupled to the processor ( Figure 3B (Not shown in the image), the processor is also coupled to the device ( Figure 3B(Not shown in the image), for example, a capacitance-to-digital converter such as the AD7746 from Analog Devices, is coupled to sensor 310 and configured to measure the capacitance detected by sensor 310. On one hand, the device is configured to repeatedly measure the capacitance between the two electrodes of sensor 310 at predetermined intervals. On one hand, the device measures the capacitance at a rate ranging from 1 to 1,000,000 times per second. On one hand, the device measures the capacitance at a rate ranging from 1,000 to 100,000 times per second. On one hand, the device measures the capacitance at a rate ranging from 10,000 to 50,000 times per second. On one hand, the device measures the capacitance at a rate ranging from 20,000 to 40,000 times per second. On one hand, the device measures the capacitance approximately 34,000 times per second. On one hand, the device measures the capacitance at this rate regardless of whether switch 342 is electrically open or closed. On one hand, when switch 342 is closed, the processor receives the measurement from the device. On one hand, the processor records multiple measurements from the device, such as ten consecutive measurements, after switch 342 is closed. On the other hand, the processor combines the multiple recorded measurements, for example by averaging, to obtain a single representative "measurement" for use in further processing. On the other hand, the processor is reset by opening switch 342 before it will record another measurement from the device.

[0079] Figure 3C Construction details of the biocapacitance scanner 300 according to this disclosure are depicted. On one hand, the guide 350 is fixedly coupled to the body 320. The bellows 360 ( Figure 3B (Not shown) is coupled to guide 350 at its lower edge and to carrier 330 at its upper edge. On one hand, bellows 360 is made of a flexible material, such as silicone, rubber, or similar material, which resists compression and acts as a compression spring, applying force to separate carrier 330 from guide 350 along axis 336. On the other hand, spring is positioned between movable element (e.g., carrier 330) and fixed element (e.g., guide 350) and is configured to provide a force that increases monotonically along translation axis 336 to separate the movable element from the fixed element.

[0080] On one hand, shaft 334 includes a nose portion 338 near switch 342. On the other hand, when sensor 310 is pressed against the patient's skin, carrier 330 (including shaft 334) is configured to move along axis 336 toward PCBA 344 until nose portion 338 contacts switch 342 and compresses switch 342 with sufficient pressure to close switch 342. On the other hand, the measurement of capacitance detected by sensor 310 occurs at the moment when applying higher pressure to sensor 310 does not affect the capacitance measurement of sensor 310, because the measurement is performed when the force first reaches a level sufficient to close switch 342.

[0081] Figures 4A-4C Depicting the possible use of this disclosure Figure 3C The position state sequence used by the scanner is indicated by the dashed circle 301.

[0082] Figure 4A A first configuration of the scanner 300 is depicted. In this first configuration, the gap 335A between the nose 338 and the PCBA 344 has a first value. The switch 342 protrudes from the surface of the PCBA 344 toward the nose 338, resulting in a smaller gap between the switch 342 and the nose 338. The flange 339 of the carrier 330 contacts the stop 352 of the guide 350, which is the highest position of the carrier 330 relative to the guide 350.

[0083] Figure 4B Depicting Figure 4A The second state of the same scanner 300. A downward force is applied to the carrier 330, causing the carrier 330 to move downward toward the PCBA 344. The gap 335B is less than Figure 4A The gap 335A is closed, and the switch 342 has been compressed sufficiently to electrically close the switch 342. Further increases in the applied force may cause the carrier 330 to move further downward toward the surface of the PCBA 344, but further compression of the switch 342 will not affect its closure. In this second state, the flange 339 and the stop 352 are not in contact with each other.

[0084] Figure 4C Depicting Figure 4B The same scanner 300, after removing some of the applied force to separate the nose 338 from the switch 342, resulting in the switch 342 being electrically deactivated, enters a third state. On one hand, the third state is related to... Figure 4A The first state is the same, and flange 339 contacts stop 352. On the one hand, gap 335C is smaller than gap 335A and there is a gap between flange 339 and stop 352 (in Figure 4C (Not shown in the image).

[0085] Figure 5Construction details of a biocapacitance scanner 500 according to this disclosure are depicted. The scanner 500 has a head 525 with a sensor 510. In this regard, the sensor 510 is mounted in a removable cap 512, which is removably coupled to a retainer 540. The retainer 540 has a convex surface 532 with a radius of curvature “R” about a center 538. The center 538 is on the surface of an interface PCBA 550. The center 538 is on the surface of the sensor 510. The center 538 is positioned on an axis 526.

[0086] On one hand, the carrier 530 is constrained by the guide feature 522 of the body 520 to translate along axis 526. On the other hand, surface 532 of the carrier 530 is concentric with surface 542 and has a radius of curvature slightly greater than R, thus allowing the retainer 540 to rotate about center 538 while maintaining contact between portions of surfaces 532 and 542. The bellows 560 is flexible and allows the retainer 540 to rotate about a first rotation axis 527 perpendicular to the translation axis 526 and a second rotation axis 528 perpendicular to both the translation axis 526 and the first rotation axis 527 (in... Figure 5 At least one of the following (not visible in the image) rotates. Since sensor 510 is fixed to cap 512, which is coupled to retainer 540, rotation of retainer 540 also causes sensor 510 to rotate. On one hand, bellows 560 applies a restoring rotational force to retainer 540 to induce retainer 540 to return to a central position relative to axes 527 and 528. On the other hand, this restoring rotational force increases monotonically as the rotational angle of retainer 540 about one or both of axes 527 and 528 increases.

[0087] Figure 6 One aspect of a visual indicator 627 according to this disclosure is depicted. A body 620 includes a front portion 624 and a rear portion 626. A translucent washer 627 is positioned between the front portion 624 and the rear portion 626. One or more light sources, such as one or more light-emitting diodes (LEDs), are positioned close to the inside of the washer 627 such that when the LEDs are activated, light from the LEDs passes through the washer 627, and a portion of the washer 627 appears to be emitting light. This luminous feature is a visual indicator. The LEDs are coupled to the processor of a scanner (in... Figure 6 (Not visible in the image), the processor is also coupled to a switch, for example... Figure 4A The processor is configured to activate the LED when the switch 342 is closed, thereby activating the visual indicator. The visual indicator is provided by a portion of the body 620 that emits light from internal illumination, such as from an internal LED.

[0088] Figure 7AAnother aspect of the biocapacitive scanner 700 according to this disclosure is depicted. This aspect includes a barcode scanning engine 730 mounted within a body 720. The scanning engine 730 includes an illuminator emitting radiation having a frequency range, such as visible light, and an imager sensitive to the radiation emitted by the illuminator within the frequency range. The body 720 includes a window 722 positioned such that a portion of the radiation projected by the illuminator passes outward through the window, and the field of view of the imager includes a portion of the window. In this way, radiation from the illuminator can illuminate an object, such as a machine-readable image printed on a patient's wristband, and the imager can acquire an image of the object, such as a barcode. In other words, the scanning engine 730 optically scans images of barcodes, 2D matrix codes, or other machine-readable encoded images. In one aspect, the scanning engine includes a signal processor that converts the image acquired by the imager into a characteristic alphanumeric string. In another aspect, the scanning engine 730 is coupled to the processor and provides the alphanumeric string to the processor, which is configured to receive the alphanumeric string from the scanning engine. In another aspect, the alphanumeric string encodes one of patient, user, observation, intervention, consumable element, durable element, location, and time. On one hand, the processor is further configured to receive multiple consecutive alphanumeric strings. On another hand, the processor is further configured to associate each consecutive alphanumeric string with one of the following: patient, user, observation, intervention, consumable element, durable element, location, and time. On another hand, the processor is further configured to associate the patient's first alphanumeric string with the consecutive alphanumeric strings. On another hand, the processor is further configured to transmit the associated alphanumeric strings to a data system.

[0089] Figure 7B An exploded view of a scanner 700 according to this disclosure is depicted. The body 720 includes a front portion 721 and a rear portion 723, with a washer 727 sandwiched between them when the front portion 721 and the rear portion 723 are in contact with each other. In this respect, the front portion 721 is coupled to a guide 725, which is coupled to a bellows 726 and a carrier 728, which is coupled to a sensor 710. The two electrodes of the sensor 710 are connected by wires (in...) Figure 7B (Not visible in the image) is coupled to device 744, for example, in this example, a capacitor-to-digital converter (CDC) located on motherboard 740. Device 744 is then communicatively coupled to processor 742. Processor 742 is also connected via cables and wires (in... Figure 7BThe processor 742 (not visible in the center) is coupled to a display 760, which may further include a touchscreen. On one hand, the processor 742 may also be coupled to one or more of a barcode scanning engine 730, a battery 764, a wireless power transmission and reception coil 766, and an audible indicator 768. In this respect, the audible indicator 768 is a piezoelectric buzzer. The display 760 is visible to the user through a transparent window 762 within an opening in the front section 721. In this respect, the processor 744 is also operatively coupled via cable to a light-emitting diode (LED) 752 mounted on a headplate 750. When the scanner 700 is assembled, the LED is positioned near a washer 727 such that light from the LED 752 shines through the translucent washer 727 to provide a visual indicator.

[0090] Figure 8A A schematic diagram of a circuit 800 configured to perform a Σ-Δ method for measuring capacitance according to this disclosure is depicted. The Σ-Δ method is well known to those skilled in the art and can be found in standard electrical engineering references; therefore, only a simplified explanation is provided herein. In this figure, the symbols... This indicates a controllable switch. On one hand, circuit 800 is part of another device, such as... Figure 7B CDC 744.

[0091] Reference voltage V 参考 (+) and V 参考 (-) The 850 is selectively coupled to the reference capacitor C via a switch. 参考 The reference capacitor is selectively coupled to ground or the input of integrator 810. The operating configuration of these switches is referenced... Figure 8C-8D This will be described. In this regard, the external capacitor C 传感器 For example, by Figure 7B A capacitor formed by the two electrodes of the sensor 710 of the scanner 700 is connected between a first terminal providing a square wave excitation voltage 830 and the input of a switch pair 854. This capacitor selectively couples the input to ground or the input of an integrator 810. The output of the integrator 810 is coupled to the integrating capacitor C. 积分 The input to comparator 820. The output of comparator 820 will be a "0" or "1" signal, which is fed to digital filter 840 and controls the configuration of switch 850, as per [reference to...]. Figure 8C-8D As described.

[0092] Figure 8B Demonstrates the following according to this disclosure Figure 8A The voltage state over the sampling interval of the circuit. The upper line “ph1” shows the configuration of the switch pair 850, where “1” indicates a configuration with V. 参考 (+) The switch connected to V is closed and connected to V 参考The (-) configuration indicates that the switch is open, while the "0" configuration indicates the opposite. The following line "ph2" shows the configuration of switch pair 852, where the "1" configuration indicates that the switch connected to the input of integrator 810 is closed and the switch connected to ground is open, while the "0" configuration indicates the opposite.

[0093] Comparator 820 responds to the input voltage only when the strobe signal is "HI" and is inactive when the strobe signal is "LO". If the input is a positive voltage when strobe is "HI", the output of comparator 820 is a voltage associated with the "1" state. If the input is a negative input when strobe is "HI", the output is a voltage associated with the "0" state.

[0094] The state sequence of circuit 800 during a single sampling period is as follows:

[0095] At time T0, switch pair 850 becomes "1", while switches 852 and 854 are in the "0" state, as follows. Figure 8C As shown, the solid line crossing the switch symbol indicates that the switch is closed. This state will be maintained for a sufficient duration "D" for the circuit voltage to stabilize to a steady state. During this period, charge Q1 is in C. 参考 Accumulation on C, and charge Q2 in C 传感器 Accumulation. Since Q = V x C, the charge of Q1 is accumulated by the voltage V. 参考 (+) and C 参考 The capacitance is determined, and both are known, therefore the value of Q1 is known. Similarly, the value of Q2 is determined by the known excitation voltage 830 and the unknown capacitance C. 传感器 Sure.

[0096] Around time T1, switch pair 850 reverses to state "0", while other switch pairs 852 and 854 remain in state "0". This buffer interval prevents both switches in each switch pair from being turned on simultaneously.

[0097] At time T2, switches 852 and 854 are configured to "1", as follows: Figure 8D As shown, charges Q1 and Q2 are therefore both supplied to the input of integrator 810. This configuration effectively uses the reference capacitor C 参考 The known capacitance and C 传感器 The unknown capacitor is compared. If the sum of Q1 and Q2 is a positive voltage, that is, greater than the other input of comparator 810 connected to ground, the output of integrator 810 will become negative. If the sum of Q1 and Q2 is a negative voltage, the output of integrator 810 will become positive.

[0098] At time T3, the strobe signal goes high, and comparator 820 responds to its input voltage, changing its output to either "1" or "0". Over a series of sampling periods, this creates a string of 1s and 0s as input to digital filter 840. This is processed within the filter to determine the relationship with C. 传感器 The measurement yields the equivalent digital value of the capacitance. This measurement can then be provided to an external device, such as... Figure 7B The processor is 742.

[0099] Figure 9A A hardware block diagram 900 depicts a method for measuring the capacitance of sensor 910 according to this disclosure. The sensor is coupled to device 920, for example, by referring to... Figure 7B The described CDC can consist of an analog signal related to capacitance measured at sensor 910, as shown in the reference. Figures 8A-8D The measured capacitance can be digitally represented via an internal integrated circuit (I). 2 C) Communication line 925 is provided to host system 930, for example Figure 7B The processor is 744.

[0100] Figure 9B A schematic diagram of an integrated system 950 for measuring, evaluating, storing, and transmitting SEM values ​​according to this disclosure is depicted. In this example, system 950 includes, as described above... Figure 7B The scanner 951 under discussion includes the ability to wirelessly communicate with a WiFi access point 962. The scanner 951 can also communicate with one or more of the following: an SEM application running on a server 960, an application running on a laptop computer 964, a smartphone 970, and other digital devices. On one hand, the laptop computer 964 and smartphone 970 are held by a user of the scanner 951 (e.g., a nurse), and the application provides feedback and information to the user. On one hand, patient information received from the scanner 951 is stored in a database 954. On one hand, information received from the scanner 951 is transmitted via a network 958 to another server 956, which stores a portion of the information in the patient's electronic medical record (EMR) 952. On one hand, information retrieved from the scanner 951 or from the database 954 or EMR 952 is transmitted to an external server 966 and then to a computer 968, such as a computer in a doctor's office providing care for the patient.

[0101] Figure 10 A workflow 1000, including scanning primary and secondary barcodes, according to this disclosure is described. The steps shown can be performed in any order, and any step can be omitted or modified.

[0102] In this example, steps 1010, 1020, and 1030 acquire identification information associated with one or more of the patient, caregiver, and current date and time. In this example, this information is encoded as a barcode or other machine-readable image such as a 2D matrix code and acquired by scanning the barcode.

[0103] Step 1040 includes acquiring information, which may include, but is not limited to, observations, conditions, other measurements such as body temperature or weight, and / or other physical artifacts such as pictures or data about nutrition and hydration. In this example, this information is acquired by scanning barcodes associated with various attributes, such as a set of barcodes for each element of a diet, whereby the user scans the barcodes for the items consumed or a series of barcodes for various amounts of fluids ingested. Step 1040 may also include scanning barcodes associated with other aspects of patient care, which may include, but are not limited to, barcodes associated with medications administered to the patient, barcodes associated with gowns or other general clothing, barcodes associated with devices such as intravenous (IV) pumps used to treat the patient and the fluids or medications administered via the IV pump, barcodes associated with treatment protocols, or any other activity or item that can be identified by machine-readable images such as barcodes.

[0104] Step 1050 includes activities associated with measuring subdural water (SEM) values ​​of the patient's body at different locations. Step 1050 includes several possible steps, depicted in this example as steps 1051 to 1056. Step 1051 includes attaching a first electrode and a second electrode (e.g., ... Figure 1A Sensors with electrodes 110 and 120 (e.g.) Figure 3B The scanner 300's sensor 310 is positioned against the patient's skin above a tissue area (e.g., the sacrum). Step 1052 includes increasing the pressure of the sensor on the patient's skin until an internal switch (such as...) is activated. Figure 4B The switch 342) is closed, initiating step 1053 to record the capacitance measured by the sensor. Step 1054 involves the user removing the sensor from the skin, which resets the measurement circuitry. The user then decides in step 1055 whether to perform further measurements or disable a series of measurements at this location. Step 1056 transmits the SEM measurements to a database that associates the capacitance measurements with the patient identification capture from step 1010. Step 1056 may further include saving the data to non-volatile local memory. Step 1056 may not save the data at all. Step 1056 may further include saving other information acquired in one or more of steps 1010 to 1050 to a database or local memory.

[0105] Step 1060 includes activity branches depending on whether treatment will be administered to this patient. These treatments may include, but are not limited to, the application of bandages, ointments, or other consumables, and the use of durable products such as foot orthotics or special mattresses. These treatments may also include, but are not limited to, procedural treatments, such as repositioning the patient at 2-hour intervals compared to a standard 8-hour interval. The treatments administered may be related to tissue damage being assessed by the scanner, but treatments related to other types of damage or symptoms are not excluded. For this example, step 1070 identifies these treatments by scanning barcodes associated with the start, change, or cessation of treatment. Step 1080 repeats this information gathering for all treatments.

[0106] Although the invention has been described with reference to specific aspects, those skilled in the art will understand that various changes can be made and elements of the invention can be substituted with equivalents without departing from the scope of the invention. Furthermore, many modifications can be made to specific aspects or materials taught in the invention without departing from the scope of the invention. Therefore, the invention is not intended to be limited to the specific aspects disclosed, but rather to encompass all aspects falling within the scope and spirit of the appended claims.

[0107] As will be apparent from the foregoing, this disclosure may be embodied in various ways, including but not limited to the following:

[0108] Example 1: A device for measuring the biocapacitance of tissue, the device comprising: a sensor including two electrodes; a movable element coupled to the sensor; a switch disposed between the movable element and a fixed element and configured to electrically close when the gap between the movable element and the fixed element is less than or equal to a predetermined value; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; and a processor coupled to the switch and the device and configured to receive the measurement from the device when the switch is electrically closed.

[0109] Example 2: The device according to Example 1, wherein the electrodes are configured such that when the sensor is positioned near the tissue, the electric field between the electrodes penetrates into the tissue.

[0110] Example 3: The device according to any one of Examples 1 to 2, wherein the device is configured to repeatedly measure the capacitance between the two electrodes at predetermined intervals.

[0111] Example 4: The device according to any one of Examples 1 to 3, wherein the sensor further includes an insulating cover layer coupled to the electrode, and wherein the insulating cover layer is configured to prevent conductive contact between the electrode and the tissue when the sensor is positioned close to the tissue.

[0112] Example 5: The device according to any one of Examples 1 to 4, wherein the measurement includes a comparison of the capacitance between the electrodes with the capacitance of a reference capacitor.

[0113] Example 6: The device according to Example 5, wherein the comparison includes using a Σ-Δ method to compare the capacitance between the electrodes with the capacitance of the reference capacitor.

[0114] Example 7: The device according to any one of Examples 1 to 6 further includes: a visual indicator coupled to the processor, wherein the processor is further configured to activate the visual indicator when the switch is closed.

[0115] Example 8: The device according to any one of Examples 1 to 7, wherein: the movable element is configured to move relative to the fixed element along a translation axis, and the gap is disposed on the translation axis.

[0116] Example 9: The device according to Example 8 further includes a spring positioned between the movable element and the fixed element, and configured to provide a force that increases monotonically along the translation axis to separate the movable element from the fixed element.

[0117] Example 10: The device according to Example 8, wherein the movable element is further configured to allow rotation about at least one of a first rotation axis perpendicular to the translation axis and a second rotation axis perpendicular to both the translation axis and the first rotation axis.

[0118] Example 11: The device according to any one of Examples 1 to 10, wherein the processor is further configured to electrically disconnect the switch after receiving a first measurement when the switch is first closed, and before a second measurement can be received.

[0119] Example 12: An apparatus for measuring the biocapacitance of tissue, the apparatus comprising: a sensor including two electrodes; a device coupled to the sensor and configured to measure the capacitance between the two electrodes; a barcode scanning engine configured to optically scan a machine-readable image and determine a first alphanumeric string encoded in the machine-readable image; and a processor coupled to the device and the engine and configured to receive the measurement from the device and receive the first alphanumeric string from the engine.

[0120] Example 13: The device according to Example 12, wherein the processor is further configured to receive a plurality of consecutive alphanumeric strings and associate each of the consecutive alphanumeric strings with one of a patient, user, observation, intervention, consumable element, durable element, location, and time.

[0121] Example 14: The device according to Example 13, wherein the processor is further configured to associate the patient’s first alphanumeric string with the consecutive alphanumeric string.

[0122] Example 15: The device according to Example 13, wherein the processor is further configured to transmit an associated alphanumeric string to a data system.

[0123] Example 16: A method for measuring the biocapacitance of tissue, the method comprising: positioning a sensor including a first electrode and a second electrode against a patient’s skin above the tissue; measuring the capacitance between the two electrodes; optically scanning a primary machine-readable image associated with the patient; determining a primary alphanumeric string encoded in the primary machine-readable image; and associating the capacitance with the primary alphanumeric string.

[0124] Example 17: The method according to Example 16 further includes: optically scanning one or more secondary machine-readable images associated with one of a user, observation, intervention, consumable element, durable element, location, and time; determining a secondary alphanumeric string encoded in each of the one or more secondary machine-readable images; and associating the secondary alphanumeric string with the primary alphanumeric string.

[0125] Example 18: The method according to Example 17 further includes: transmitting the primary and secondary alphanumeric strings to a data system.

Claims

1. A device for measuring the biocapacitance of tissues, the device comprising: The sensor includes two electrodes. A movable element coupled to the sensor, wherein the movable element includes a carrier, and wherein the movable element is configured to move relative to a fixed element along a translational axis. A bellows, coupled to the movable element, wherein the bellows is configured to allow the movable element to rotate about at least one of a first rotational axis perpendicular to the translational axis and a second rotational axis perpendicular to both the translational axis and the first rotational axis. A switch, disposed between the movable element and the fixed element, and configured to electrically close when the gap between the movable element and the fixed element is less than or equal to a predetermined value. A device, coupled to the sensor and configured to measure the capacitance between the two electrodes, and A processor, coupled to the switch and the device, and configured to receive the measurement from the device when the switch is electrically closed.

2. The device of claim 1, wherein the electrodes are configured such that when the sensor is positioned near the tissue, the electric field between the electrodes penetrates into the tissue.

3. The apparatus of claim 1, wherein the means is configured to repeatedly measure the capacitance between the two electrodes at predetermined intervals.

4. The device of claim 1, wherein the sensor further includes an insulating cover layer coupled to the electrode, and wherein the insulating cover layer is configured to prevent conductive contact between the electrode and the tissue when the sensor is positioned close to the tissue.

5. The apparatus of claim 1, wherein the measurement comprises comparing the capacitance between the electrodes with the capacitance of a reference capacitor.

6. The device of claim 5, wherein the comparison comprises using a Σ-Δ method that compares the capacitance between the electrodes with the capacitance of the reference capacitor.

7. The device according to claim 1, further comprising: A visual indicator coupled to the processor, wherein the processor is further configured to activate the visual indicator when the switch is closed.

8. The device according to claim 1, wherein: The gap is positioned on the translation axis.

9. The device of claim 1, further comprising a spring positioned between the movable element and the fixed element, and configured to provide a force that increases monotonically along the translation axis to separate the movable element from the fixed element.

10. The device of claim 1, wherein the processor is further configured to electrically disconnect the switch after receiving a first measurement when the switch is first closed, and before being able to receive a second measurement.

11. The device of claim 1, wherein the two electrodes are configured with a plurality of interleaved fingers.

12. The device of claim 1, wherein the two electrodes comprise a center electrode and a ring electrode.

13. The device of claim 1, wherein the sensor further comprises a substrate.

14. The device of claim 13, wherein the two electrodes are disposed on a common surface of the substrate and are coplanar with each other.

15. The device of claim 7, wherein the visual indicator is provided by a portion of the device that emits light from internal illumination.

16. The device of claim 1, wherein the sensor is mounted in a removable cap, the removable cap being removably coupled to a retainer.

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