Systems and methods for measuring tissue parameters using capacitive tactile sensors - Patents.com

Abstract

Apparatus and methods are described for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of skin or other soft tissue within a subject by measuring variations in tactile pressure on the surface of the skin or other tissue being investigated through the use of a capacitive tactile sensor. The capacitive tactile sensor includes a substrate having at least one exposed window and a plurality of electrodes disposed within a housing, an insulating layer, a non-conductive compressible membrane and covering positioned on the insulating layer, where at least a portion of the membrane is accessible through the exposed window, and a controller configured to calculate at least one parameter of the subject's tissue. Methods for measuring tissue parameters within a subject and for performing self-guided testing on the subject's tissue are also described.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 875,485, filed July 17, 2019, which is incorporated herein by reference in its entirety. [Background technology]

[0002] The key to successful treatment of many forms of cancer lies in early detection, and early detection and identification of cancerous growths is highly dependent on the availability, relative cost, effectiveness, and associated risks of existing sensors and screening technologies. Currently, there are a variety of different sensors and tools used to probe the mechanical properties of and image soft tissue.

[0003] One type of conventional soft tissue sensor uses an external force applicator to induce displacement and an external displacement gauge to measure the resistive force. The external force applicator may be hydraulic or piezoelectric, and the external displacement gauge may be optical or piezoelectric.

[0004] Exemplary soft tissue imaging tools include computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), T-scan (TS), and ultrasound elastography (UE). CT scans use computer software to acquire 360-degree x-rays and reconstruct 3D tissue structures. MRI scans use strong magnetic fields and radio waves to generate diagnostic tissue images. US scans transmit radio waves through tissue and capture echoes to image tissue structures. TS measures low-level biocurrents to generate real-time images of the tissue's electrical impedance properties. UE scans evaluate the echo time through tissue under a constant mechanical stress and compare it to that of the same tissue when unstressed. This results in a tissue strain map, from which 2D images of elastic modulus distribution can be generated using conventional back-calculation techniques.

[0005] Tactile imaging tools, such as mammography, use array pressure sensors to probe spatial tissue stiffness variations. Currently, mammography is used in breast cancer screening to detect abnormal tissue through tissue density contrast. Mammography is the only breast cancer screening technique approved by the FDA and has a typical sensitivity of 85%, which decreases to 65% for radio-dense breasts. However, these screening processes have a high rate of false positives. In fact, only approximately 15–30% of breast biopsies result in a diagnosis of malignancy. While mammography is effective in screening women over 40 years of age, it is less effective in screening women with dense breast tissue.

[0006] Because many tissues harboring abnormal growths are stiffer under compression than the surrounding normal tissue, detecting changes in tissue stiffness is becoming an increasingly important factor in detecting potentially abnormal tissue. For example, breast cancer is a calcified tissue known to be over seven times stiffer than normal breast tissue. Similarly, blood vessels with plaque attached are also stiffer than normal, healthy blood vessels.

[0007] U.S. Patent No. 6,277,623, incorporated herein by reference, discloses a piezoelectric finger sensor that can be used to detect tumors by measuring tissue stiffness. Tumor mobility is assessed from the ratio of the tumor's shear modulus to elastic modulus (G / E) ratio, or by highly sensitive direct tumor mobility measurements using two piezoelectric finger sensors: one for compressing and one for measuring the tumor's resulting movement. The patent concludes that the G / E ratio is greater in the tumor region than in the surrounding normal tissue, and that the significantly greater G / E ratio in the cancer region indicates that the tumor has less mobility under shear than under compression compared to the surrounding normal tissue. The patent concludes that these measurements may offer potential for noninvasive breast cancer screening, but does not disclose methods for determining the grade, aggressiveness, or tumor type.

[0008] U.S. Patent No. 6,277,623, incorporated herein by reference, discloses a piezoelectric sensor system for assessing tissue, including determining whether the tissue contains abnormal growths. The disclosed system uses an array of piezoelectric elements that actuate in a first direction toward the tissue, and then record the relative positions of these piezoelectric elements to approximate the tissue's stiffness. Such sensors are very difficult to calibrate and fall out of calibration after continued use, or even after accidental contact. Therefore, they are not suitable for use by amateurs. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] U.S. Patent No. 7,497,133 [Patent Document 2] U.S. Patent No. 8,562,546 Summary of the Invention [Problem to be solved by the invention]

[0010] Thus, there exists a significant need for an accurate, non-invasive, inexpensive, portable, and easy-to-use system for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of skin or other soft tissue.The present invention satisfies this need. [Means for solving the problem]

[0011] In one embodiment, a device for measuring tissue parameters within a subject includes a housing having at least one exposed window, a substrate having a plurality of electrodes disposed within the housing, an insulating layer positioned over the electrodes, a flexible membrane positioned over the insulating layer, at least a portion of which is accessible through the exposed window, and a controller disposed within the housing configured to calculate at least one parameter of the tissue of the subject based on capacitance measured between the electrodes. In one embodiment, the flexible membrane comprises foam. In one embodiment, the foam has a hardness ranging from 00-0 to 00-20. In one embodiment, the plurality of electrodes comprises at least two electrodes. In one embodiment, each of the plurality of electrodes is 1 mm thick. 2 ~16mm 2In one embodiment, the device includes a visualization device communicatively connected to the controller, where the visualization device has a display. In one embodiment, the controller is connected to the visualization device via a Bluetooth® connection. In one embodiment, the device includes a conductive element configured to provide a voltage reference to a surface in contact with the flexible membrane. In one embodiment, the conductive element is positioned to substantially surround the exposure window. In one embodiment, the at least one parameter comprises tissue stiffness. In one embodiment, the subject's tissue comprises breast tissue.

[0012] In one embodiment, a method for measuring a tissue parameter within a subject includes positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of the subject, measuring a capacitance between two electrodes of the plurality of electrodes, determining a thickness of the flexible material based on the capacitance, and calculating a tissue parameter based on the thickness of the flexible material. In one embodiment, the method includes transmitting data selected from a group consisting of capacitance, thickness, and tissue parameter to a visualization system. In one embodiment, the method includes measuring a plurality of capacitance values ​​between a set of electrode pairs and displaying a diagram of the parameter values ​​across the tissue surface on the visualization system. In one embodiment, the tissue parameter is stiffness. In one embodiment, the method includes making a provisional diagnosis based on the tissue parameter.

[0013] In one embodiment, a method for performing an inductive self-test on a subject's tissue includes positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of the subject, measuring a capacitance between two of the plurality of electrodes, calculating a tissue parameter based on the capacitance, determining in a controller an instruction for the subject based on the tissue parameter, and issuing the instruction to the subject to induce the subject to operate the handheld device. In one embodiment, the instruction is an auditory instruction issued through a speaker. In one embodiment, the instruction is configured to induce the subject to move the device to a new location on the tissue. In one embodiment, the instruction includes a visual cue presented on a display.

[0014] In one embodiment, a capacitive tactile sensor device for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of skin or other soft tissue within a subject by measuring variations in tactile pressure on the skin or other tissue surface includes a housing having at least one exposed window and an exposed conductive surface positioned to be in contact with the conductive surface at all times while an operator or the device is operating the device; a substrate disposed within the housing having a plurality of pairs of separate, coplanar, co-located electrodes configured as a Cartesian grid on an electrically non-conductive material and configured such that any two adjacent electrodes are electrically independent and independently stimulable by an externally generated stimulation voltage or current signal, thereby creating a capacitor between each such electrode pair, with the space above the outward-facing surface of the electrode grid acting as a dielectric; a layer of insulating material positioned on the outward-facing surface of the electrode grid; a homogeneous compressible non-ferrite and non-conductive membrane covering the insulating layer formed thereon, the membrane (a) having a uniform thickness across the entire surface area of ​​each pair of adjacent electrodes forming a capacitor and across the entire surface area of ​​the Cartesian grid of electrodes, (b) having a fixed, uniform and known compression ratio and hardness across the entire surface area of ​​the Cartesian grid of electrodes, and (c) having a steady-state equilibrium shape such that its volume remains constant when no external force is applied; and a non-conductive cover material positioned on an outward-facing surface of the homogeneous compressible non-ferrite and compressible membrane, at least a portion of which is accessible through an exposure window in the housing and serves as the outward-facing surface of the sensor, and which together with the membrane effectively replaces air as a dielectric for the capacitor created by each pair of adjacent electrodes, one functioning as a transmitting electrode and one functioning as a receiving electrode, wherein the sensor surface has electromechanical properties including normal surface pressure of a conductive tissue:a non-conductive cover material configured to be fully and firmly placed in contact with a surface of a subject's tissue so as to disrupt the electric field within a dielectric comprised of the compressible membrane and to disrupt capacitive coupling between associated pairs of co-planar electrodes, wherein the sensor input device induces and generates at least one signal in response to pressure applied on the sensor surface by contact with the skin or other soft tissue surface and the resulting compression of the compressible membrane and disruption of capacitive coupling between associated pairs of co-planar electrodes in accordance with the changing composition and properties of the underlying tissue structure as an indicator of the location, mechanics, and specific characteristics of the local area of ​​relatively stiff tissue underlying the area of ​​the skin or other tissue surface being investigated; and (a) (i) a non-conductive cover material configured to be fully and firmly placed in contact with a surface of a subject's tissue so as to disrupt the electric field within a dielectric comprised of the compressible membrane and to disrupt capacitive coupling between associated pairs of co-planar electrodes, wherein the sensor input device induces and generates at least one signal in response to pressure applied on the sensor surface by contact with the skin or other soft tissue surface and the resulting compression of the compressible membrane and disruption of capacitive coupling between associated pairs of co-planar electrodes in accordance with the changing composition and properties of the underlying tissue structure as an indicator of the location, mechanics, and specific characteristics of the local area of ​​relatively stiff tissue underlying the area of ​​the skin or other tissue surface being investigated; and (b) a controller disposed within a housing comprised of one or more integrated circuits and a processor configured to (i) receive and process the signals induced, generated, and transmitted by the one or more IC capacitive sensor chips to calculate one or more parameters of the underlying tissue structure based on changes in perceived capacitance between adjacent associated electrode pairs generated by pressure applied against the sensor surface by contact with the skin or other soft tissue surface, and (ii) be in communicative contact with a visualization device having a display and integrated storage device. In one embodiment, the homogeneous compressible non-ferrite and non-conductive membrane is made of polyurethane, silicone,or a thermoplastic elastomer foam. In one embodiment, the foam has a hardness in the range of 00-0 to 00-20. In one embodiment, the plurality of electrodes includes at least two electrodes. In one embodiment, each of the plurality of electrodes has a thickness of 1 mm, 2 ~16mm 2 In one embodiment, the device includes a visualization device communicatively connected to the controller, where the visualization device has a display. In one embodiment, the controller is connected to the visualization device via a Bluetooth® connection. In one embodiment, the device includes a conductive element on the exterior of the housing configured to provide a voltage reference used for all subsequent capacitive calculations. In one embodiment, the device includes a grounding pad or strap providing conductive contact between an uninsulated portion of the electrode plane and the exterior surface of the capacitive sensor configured to provide a voltage reference used for all subsequent capacitive calculations. In one embodiment, the at least one parameter includes tissue stiffness. In one embodiment, the subject's tissue includes breast tissue.

[0015] In one embodiment, a method for documenting, measuring, and mapping the size, shape, and location of underlying palpable lesions on the surface of skin or other soft tissue within a subject using capacitive tactile sensing to measure normal tactile pressure variations on the surface of the skin or other soft tissue area of ​​the tissue surface includes the steps of positioning a handheld device having a plurality of electrodes and a predetermined amount of non-conductive compressible material and covering in contact with a substantially internal skin or tissue surface area of ​​the subject; determining a baseline reference capacitance of the subject from measurements taken by an operator from a lesion-free area of ​​the tissue; determining a baseline potential reference from the operator through conductive contact between the operator and the handheld device; and The method includes the steps of: positioning a handheld device in contact with a surface area of ​​the skin or tissue being investigated; measuring a capacitance between two electrodes of the plurality of electrodes resulting from contact with the surface area of ​​the skin or tissue being investigated; measuring a variation in perceived capacitance between adjacent associated electrode pairs with reference to a baseline potential reference created by pressure applied to the sensor surface (compressible membrane and covering) resulting from a disruption to the capacitive coupling between adjacent associated electrode pairs created by contact with the skin or surface of the tissue being investigated; and calculating one or more tissue parameters based on the variation in perceived capacitance from the baseline potential reference. In one embodiment, the method includes transmitting data selected from the group consisting of perceived capacitance, thickness, and tissue parameters to a visualization system. In one embodiment, the method includes measuring a plurality of capacitance values ​​between the pairs of electrodes and displaying on a visualization device a diagram of the parameter values ​​across the tissue surface. In one embodiment, the tissue parameter is stiffness.

[0016] In one embodiment, a method for performing an inductive self-test on a subject's tissue includes positioning a handheld device having substantially a plurality of electrodes and a predetermined amount of flexible material in contact with a body region of the subject, measuring a capacitance between two of the plurality of electrodes, calculating a tissue parameter based on the capacitance, determining instructions for the subject based on the tissue parameter in a controller, and issuing instructions to the subject to guide the subject to operate the handheld device. In one embodiment, the instructions are auditory instructions issued through a speaker. In one embodiment, the instructions are configured to guide the subject to move the device to a new location on the tissue. In one embodiment, the instructions include visual cues presented on a display.

[0017] In one aspect, a method for dynamically calibrating data received from at least one sensor includes obtaining a plurality of data values ​​from the at least one sensor; calculating a first mean and a first standard deviation of the plurality of data values; obtaining a subset of the plurality of data values ​​whose values ​​are within one standard deviation of the first mean; calculating a second mean from the subset of the plurality of data values ​​as a baseline; and subtracting the baseline value from the plurality of data values ​​to generate a calibrated data set.

[0018] In one embodiment, the method further comprises obtaining a second plurality of data values; calculating a third mean and a third standard deviation of the first and second plurality of data values; obtaining a second subset of the first and second plurality of data values ​​whose values ​​are within one standard deviation of the third mean; calculating a fourth mean from the second subset of the plurality of data values ​​as a second baseline; and subtracting the second baseline value from the first and second plurality of data values ​​to generate a calibrated data set.

[0019] In one embodiment, the method further comprises displaying a three-dimensional surface plot of the calibrated data set, displaying a baseline, and providing visual feedback when the baseline value is within an optimal range. In one embodiment, the visual feedback comprises changing a color of a region of the three-dimensional surface plot. In one embodiment, the method further comprises calculating a moving average of the plurality of data values, and calculating a first mean and a first standard deviation from the moving average.

[0020] In one embodiment, the method further comprises comparing the moving average to maximum and minimum threshold values, capturing a plurality of data values ​​or a moving average when the moving average is between the maximum and minimum threshold values, and storing the captured data values ​​on a non-transitory computer-readable medium when the moving average remains between the maximum and minimum threshold values ​​for a defined period of time, which in one embodiment is at least 3 seconds.

[0021] The above-mentioned objects and features, as well as other objects and features, will become apparent to those skilled in the art from reference to the following description and the accompanying drawings, which are included to provide an understanding of the invention and are incorporated into and constitute a part of this specification, and in which like reference numerals represent like elements. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram of a capacitive sheet according to one embodiment. [Figure 2] FIG. 1 is a diagram of a capacitive sheet according to one embodiment. [Figure 3A] FIG. 2 illustrates a cross section of an electrode pair on a substrate according to one embodiment. [Figure 3B] FIG. 1 illustrates a cross-section of a portion of a capacitive touch sensor device according to one embodiment. [Figure 3C]1 is an exemplary diagram of normal pressure on the surface of tissue applied to a portion of a capacitive touch sensor device according to one embodiment. [Figure 3D] 1A-1C illustrate an exemplary cross-section of a portion of a capacitive tactile sensor input device in contact with an uneven surface according to one embodiment. [Figure 4A] 1A and 1B show first and second embodiments of a housing having an operator ground contact. [Figure 4B] 1A and 1B show first and second embodiments of a housing having an operator ground contact. [Figure 5] FIG. 2 is a diagram of a visualization display according to one embodiment. [Figure 6A] FIG. 2 is a diagram of a visualization display according to one embodiment. [Figure 6B] FIG. 2 is a diagram of a visualization display according to one embodiment. [Figure 6C] FIG. 2 is a diagram of a visualization display according to one embodiment. [Figure 7] FIG. 1 illustrates a method of the present invention according to one embodiment. [Figure 8] FIG. 10 shows a chart of sample comparison data for piezoelectric versus capacitive sensors according to an example experiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] It should be understood that, for purposes of clarity, the figures and descriptions of the present invention have been simplified to show elements relevant for a clear understanding of the present invention, while excluding many other elements found in the related systems and methods. Those skilled in the art may recognize that other elements and / or steps are desirable and required in implementing the present invention. However, because such elements and steps are well known in the art and because they do not facilitate a better understanding of the present invention, descriptions of such elements and steps are not provided herein. The disclosure herein covers all such variations and modifications to such elements and methods known to those skilled in the art.

[0024] Unless defined otherwise, 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 invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, exemplary methods and materials are described.

[0025] As used herein, each of the following terms has the meaning associated with it in this section.

[0026] The articles "a" and "an" are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, "an element" means one element or more than one element.

[0027] As used herein, "about" when referring to measurable values ​​such as amounts, durations, and the like, is meant to encompass variations of ±20%, ±10%, ±5%, ±1%, and ±0.1% from the stated value, as appropriate depending on the variation.

[0028] Throughout this disclosure, various aspects of the invention may be presented in a range format. It should be understood that the description in range format is for convenience and brevity only and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all possible subranges as well as each individual numerical value within that range. For example, the description of a range such as 1 to 6 should be considered to have specifically disclosed each individual numerical value within that range, such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, etc., as well as subranges such as 1, 2, 2.7, 3, 4, 5, 5.3, 6, and all whole and partial increments therebetween. This applies regardless of the breadth of the range.

[0029] In some aspects of the present invention, software that executes the instructions provided herein may be stored on a non-transitory computer-readable medium, where the software performs some or all of the steps of the present invention when executed on a processor.

[0030] Aspects of the present invention relate to algorithms implemented in computer software. While particular embodiments may be described as being written in a particular programming language or as running on a particular operating system or computing platform, it should be understood that the systems and methods of the present invention are not limited to any particular computing language, platform, or combination thereof. Software executing the algorithms described herein may be written in, compiled, or interpreted in, any programming language known in the art, including, without limitation, C, C++, C#, Objective-C, Java, JavaScript, Python, PHP, Perl, Ruby, or Visual Basic. It should further be understood that elements of the present invention may be executed on any acceptable computing platform, including, without limitation, a server, a cloud instance, a workstation, a thin client, a mobile device, an embedded microcontroller, a television, or any other suitable computing device known in the art.

[0031] Portions of the present invention are described as software running on a computing device. While the software described herein may be disclosed as running on one particular computing device (e.g., a dedicated server or workstation), it is understood in the art that software is inherently portable, and that most software running on a dedicated server may, for purposes of the present invention, run on any of a variety of devices, including desktop or mobile devices, laptops, tablets, smartphones, watches, wearable electronics or other wireless digital / cellular phones, televisions, cloud instances, embedded microcontrollers, thin client devices, or any other suitable computing device known in the art.

[0032] Similarly, portions of the present invention are described as communicating over various wireless or wired computer networks. For purposes of this invention, the terms "network," "networked," and "networking" should be understood to encompass wireless connections, including wired Ethernet, fiber optic connections, various 802.11 standards, cellular WAN infrastructures such as 3G or 4G / LTE networks, Bluetooth, Bluetooth Low Energy (BLE), or Zigbee communications links, or any other method by which one electronic device has the ability to communicate with another. In some embodiments, elements of the networked portions of the present invention may be implemented over a virtual private network (VPN).

[0033] The term "abnormal" when used in the context of an organism, tissue, cell, or component thereof means an organism, tissue, cell, or component thereof that differs in at least one observable or detectable characteristic (e.g., age, treatment, time of day, etc.) from an organism, tissue, cell, or component thereof that exhibits "normal" (expected) individual characteristics. A characteristic that is normal or expected in one cell or tissue type could be abnormal in a different cell or tissue type.

[0034] As used herein, the term "diagnosis" refers to the determination of the presence of a disease or disorder. In some embodiments of the present invention, methods are provided for performing diagnostics that allow the determination of the presence of a particular disease or disorder.

[0035] As used herein, the term "screening" means the detection, documentation, measurement, and / or mapping of the size, shape, and location of abnormal features in a subject's tissue that may signal the potential presence of a disease or disorder that warrants further investigation.

[0036] The terms "patient," "subject," "individual," and the like, are used interchangeably herein and refer to any animal or cells thereof amenable to the methods described herein, whether in vitro or in situ. In certain non-limiting embodiments, a patient, subject, or individual is a human.

[0037] One aspect of the present invention relates to a device that detects tissue surface characteristics, including normal surface pressure and variations in such surface pressure, on an area being investigated; these characteristics may signal the presence of underlying tissue abnormalities, such as, for example, a mass, lesion, cyst, or tumor. Exemplary devices of the present invention may be hand-held or have a compact form factor. In some embodiments, devices of the present invention have multiple parts, while in other embodiments, the device is a self-contained and self-powered diagnostic device.

[0038] A device of the present invention can include a capacitive sheet, as shown in FIG. 1. Capacitive sheet 101 can be rigid, flexible, or conformable and can be fabricated from any suitable material, such as, for example, Kapton, fiberglass-reinforced epoxy, or reinforced phenolic. The exemplary capacitive sheet depicted includes a plurality of capacitive elements 102, 103. While the depicted sheet includes nine capacitive elements or electrodes in a 3×3 Cartesian grid configuration, it should be understood that a capacitive sheet of the present invention can include any number of individual capacitive elements, for example, in a range from 2 to over 20×20 matrices.

[0039] Although the depicted capacitive elements are square, it should be understood that the capacitive elements can be any shape, including, without limitation, a circle, a triangle, a hexagon, or a square. The individual capacitive elements can be made from any conductive material, including, without limitation, copper, gold, silver, steel, aluminum, carbon nanotubes, stainless steel, or platinum.

[0040] The capacitive elements in the capacitive sheet are typically, for example, 1 mm 2 ~16mm 2The capacitive elements may be any size ranging from 0.5 mils to 3 mils, and may have thicknesses ranging from 0.5 mils to 3 mils. In some embodiments, all capacitive elements in a capacitive sheet are substantially the same size, while in other embodiments, a capacitive sheet of the present invention may include multiple capacitive elements having different sizes. Similarly, different capacitive elements on the same sheet may be made from the same or different materials or have the same or different shapes.

[0041] 2, an alternative capacitive sheet 201 is shown. Exemplary sheet 201 includes substantially square capacitive elements 202 and 203, as well as substantially circular capacitive elements, such as 204.

[0042] The individual capacitive elements can be interconnected in some embodiments, and can be configured so that any two adjacent electrodes are electrically independent and independently excitable. In such a configuration, each pair of electrodes can be used as a separate capacitor, with the space above the surface of the capacitive sheet (including any material disposed or arranged on top of it) acting as a dielectric.

[0043] 3A-3D, an exemplary device of the present invention is shown in cross-sectional view. In FIG. 3A, the base device includes a substrate 301 having a plurality of capacitive elements, including 303 and 304, as well as an insulating surface 302 disposed on the elements. Elements 303 and 304 are electrically isolated from one another, and when element 303 is held at a first potential and element 304 is held at a second potential, an electric field 305 is generated between the two elements. In the example of FIG. 3A, the dielectric of the capacitor generated between elements 303 and 304 is air. Insulating surface 302 can be fabricated from any insulating material, including, without limitation, an epoxy laminate material such as FR-4 or standard solder mask material. Insulating surface 302 can have a thickness of up to 80 microns.

[0044] Referring to FIG. 3B, an alternative design includes a membrane 306 disposed on the insulating surface 302. The membrane 306 may be a homogeneous, mechanically compressible, non-ferrite, and non-conductive membrane that effectively replaces air as a dielectric for the capacitor created by two adjacent electrodes. The membrane may have a substantially uniform thickness, although in some embodiments, the thickness may vary, e.g., to allow the device to conform to curved or irregular body regions. The membrane provides mechanical isolation between the electrode surface and any external surface that abuts the membrane's opposite surface in a plane parallel to the surface facing the electrode plane. The membrane may be covered by a loose-fitting, non-conductive material, such as nitrile.

[0045] The membrane 306 can be configured to have a substantially fixed and uniform density, compression ratio, and hardness across the entire substrate or an exposed subset of the substrate. Suitable materials for use within the membrane of the devices of the present invention include silicone, compressible foam, or saline encapsulant. The Shore hardness of the material can range from 0-20 Shore 00. The dielectric constant of the material can range from 1.0 to about 5.0. The membrane material can be configured to have a steady-state equilibrium shape to which it returns when no external force is applied.

[0046] As shown in FIG. 3C , when an external force is applied, for example, by finger 307, membrane 306 deforms, thereby changing the characteristics of electric field 305 and, therefore, the capacitance of the capacitor generated between capacitive elements 303 and 304. In the illustrated device, the external force is provided by normal pressure on the surface of the subject's skin or other tissue in the area being investigated. This change in capacitance can be measured using any suitable means in the art, such as, for example, by a series or parallel resistive / inductive element, or by measuring the impedance response of the capacitor by itself or in combination with other fixed or variable resistive, inductive, or capacitive elements. As a result, the location and magnitude of the force exerted by the external force can be measured and tracked over time.

[0047] Another example is shown in Figure 3D, which shows an exemplary device used in conjunction with an external surface 308 that has dielectric properties such that, when placed on the membrane, the dielectric constant, and therefore the electric field pattern, is perturbed between adjacent pairs of electrodes. This results in a change in capacitance, which can be measured, for example, using the methods outlined above. Suitable external surfaces for use with the device of the present invention include, without limitation, human or other animal skin, human or other animal organs, or any ferrous, conductive, or semi-conductive material. When normal pressure from the surface of the tissue being investigated is applied between the external surface 308 and the capacitive elements 303 and 304, the membrane 306 deforms as shown. When the pressure is not uniform, such as when the external surface 308 is tissue with variable stiffness across the surface applied to the membrane 306, the membrane 306 will deform non-uniformly. For example, the membrane may deform in a manner that reflects underlying tissue structure, such as a hard or soft lesion. Non-uniform membrane strain across a surface having multiple capacitive elements will produce a measurable variation in the distance between the external surface and the electrode surface across the electrode array. The varying distance will affect the overall dielectric perceived by any adjacent pair of capacitors, such as adjacent pair 303 and 304. This will affect the dielectric constant of each capacitor, which can be used to calculate the distance between the external surface and the electrode surface across the array, which can then be used to calculate the official force / square millimeter across the electrode surface. The change in capacitance is related to a change in perceived dielectric constant that is linearly proportional to the measured capacitance.

[0048] Also shown in FIG. 3D is an electrically conductive element 309. Element 309 is configured to provide a stable reference potential relative to exterior surface 308. Element 309 can be referenced, for example, to a ground potential within the device designed to provide a ground reference to the subject's skin in the body region being evaluated. Alternatively, the ground reference can be obtained from conductive contact with the operator's skin. A fixed reference potential on the exterior surface can significantly improve the quality of measurements across the electrode pair in some embodiments. It is contemplated herein that element 309 can be formed from any conductive material, including, without limitation, copper, gold, silver, or platinum. In some embodiments, element 309 is substantially fabricated from a first material, such as a metal, and is coated on an edge near exterior surface 308 with a second conductive or semi-conductive material to provide greater user comfort. In one embodiment, membrane 306 defines a treatment area, such as a circular, oval, square, rectangular, or elliptical treatment area. The conductive element 309 may extend substantially around the periphery or edge of the treatment area to maximize the likelihood of good electrical contact between the conductive element 309 and the outer surface 308 (e.g., the subject's skin).

[0049] The apparatus of the present invention can further include a controller having specialized circuitry for reading capacitance values ​​from the various electrode pairs. The controller can comprise any computing device, such as an integrated microcontroller or processor, and can further comprise a certain amount of volatile and / or non-volatile memory on which instructions can be stored for carrying out the steps of the method of the present invention. In some embodiments, the controller has instructions configured to iterate through several or all possible electrode pairs presented as an array grid in succession to provide continuous measurements of capacitance and, therefore, the properties of the exterior surface 308 in contact with the membrane 306. In some embodiments, the controller can utilize any of several commercially available chips or modules suitable for capacitive sensing and related calculations.

[0050] As described herein, system embodiments are configured to detect and assess subcutaneous soft tissue lesions by measuring and quantifying tactile pressure variations at the surface of the tissue using capacitive sensing and measurement using multiple pairs (including at least one pair) of separate, coplanar electrodes co-located on a substrate disposed within a housing, the electrodes configured as a Cartesian grid, and any two adjacent electrodes being electrically independent and independently excitable, thereby creating a capacitance between the electrode pair. Thus, the system can be used as a capacitive sensor. In certain embodiments, a sensor surface made of a loose-fitting, non-conductive cover material is disposed on the outer-facing surface of a compressible, non-ferrite, non-conductive membrane positioned on the outer-facing surface of the electrode grid, which serves as a dielectric for the capacitor created by any two adjacent electrodes (one serving as a transmitting electrode and one as a receiving electrode). The sensor surface is configured to be placed in contact with tissue with sufficient pressure to slightly compress the compressible dielectric. The term "slight compression" may refer, in certain instances, to the application of a minimal amount of pressure sufficient to ensure that the sensor surface makes complete and firm contact with the tissue. At this point, the tissue's electromagnetic properties will disrupt the electric field within the dielectric and disrupt capacitive coupling between the associated pair of coplanar electrodes. Disturbances in capacitance are measured by utilizing a calibrated baseline set of measurements acquired by the operator from a lesion-free area of ​​the tissue, and then determining the difference between such baseline measurements and the capacitive measurements obtained from each pair of electrodes, as a whole, facing the surface area of ​​the tissue being investigated. According to one embodiment, the potential of the tissue in contact with the sensor, i.e., with the patient, during the complete set of measurements (including the baseline) is assumed to remain constant and not necessarily to be 0 volts.It can also be assumed that the potential of tissue in contact with the device enclosure, i.e., the operator holding the device, is constant over the complete set of measurements (including the baseline) and, again, not necessarily 0 volts. Tissue stiffness classification is achieved by measuring the difference in tactile pressure of the tissue's surface on the sensor surface. These pressures are then quantified by the measured capacitance between coplanar electrodes. The measured capacitance is compared to the baseline set of measurements defined above, and relative measurements are then quantified for each pair of electrodes. For the relative measurements to be consistent, it must be determined that the reference voltage potential used in both the baseline and measured capacitance is exactly the same. This constant potential can be obtained (1) from the patient's tissue or (2) from the operator's tissue, as described above. Option (1) can be used with the grounding option already described. Option (2) requires the placement of a conductive surface on the device housing configured to be in constant contact with the operator, including when making the baseline and measured capacitance measurements for relative tissue stiffness. 4A and 4B, a conductive surface is constructed on a surface of a portion of a housing (e.g., a handheld portion) and is configured to provide a voltage reference from an operator. Referring to FIG. 4A, the exemplary housing includes a gripping surface 401 that connects two housing portions 402 and 403. In the depicted embodiment, housing portion 402 includes an upper gripping surface 413. In some embodiments, gripping surface 413 includes one or more buttons or other control elements that allow an operator to control the sensor assembly, for example, to start or stop measurements or to zero the sensor for calibration purposes. In the depicted embodiment, gripping surface 401 is held in place by two pegs 411 (a second peg is on the opposite interior surface of 401) that mate with two corresponding holes 412 on housing portions 402 and 403.In some embodiments, one or both of gripping surfaces 401 and 413 include a conductive element or finish that allows the sensor assembly to measure a reference voltage from the operator's skin during use.

[0051] 4B, an exemplary housing includes an upper handle surface 404 and a lower ring 405. In various embodiments, either or both of the handle 404 and the ring 405 may include a conductive element or fish configured to measure a reference voltage from the operator's skin (in the case of the handle 404) or the subject's skin (in the case of the ring 405). In some embodiments, the user and the subject are the same, for example, in the case of self-testing.

[0052] Embodiments of the device may be contained within a housing designed for self-testing. The integrated device may include a power source, such as a battery, power management hardware, and one or more communication devices, such as a wired or wireless communication device, for sending or receiving data, configuration information, or operating instructions to or from a remote computing device. In one embodiment, the integrated device has a Bluetooth transceiver, and the remote computing device may be paired with the integrated device to send and receive data.

[0053] The system of the present invention includes the sensor device described above for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of a subject's skin or other soft tissue by measuring variations in tactile pressure on the tissue surface within the subject's body region, in combination with a wired or wireless connection to a visualization computing device containing software for visualizing the results, and in some embodiments, interpreting the results to provide a preliminary analysis. The visualization computing device may include a wired or wireless transceiver for receiving, processing, displaying, and storing data from the diagnostic device, which transceiver could be configured to use any wired or wireless communication protocol known in the art. In some embodiments, the data connection between the visualization device and the sensor device is encrypted.

[0054] In some embodiments, the systems of the present invention are configured to perform a self-guided examination or assessment by the subject. Such systems include a guidance element, such as one integrated within one or both of the sensor device and visualization device described above. The guidance element can be configured to receive information from one or both of the sensor device and visualization device and provide instructions or prompts to the subject based on that information. The instructions or prompts may include visual, auditory, or tactile feedback. In one example, the sensor device can be positioned on the subject's tissue so that the structure of interest is detected along the top edge of the device. The guidance element can then issue instructions to the subject to reposition the device, for example, to move the device further upward to better center the structure of interest within the device's detection area. The guidance element can also instruct the user to reposition the device, for example, to span the entire breast. In some cases, the guidance can instruct the user to switch from one breast to the other.

[0055] Another aspect of the present invention includes a method for visualizing a structure of interest within a subject's tissue. Using the system described above, a subject can position a sensor device having a sensing surface over a body region with the sensing surface in substantially direct contact with the skin of the body region. Although not required, the subject may then press a button or activate some other control to initiate the sensing process. As a result, the device collects data from the tissue region in contact with the sensing surface and performs calculations based on the data. Processing may include noise reduction algorithms and basic smoothing algorithms. The processed and / or raw data is then transmitted via a wired or wireless connection to a visualization device, which can perform further calculations based on the received data. The final processed data is then used to generate a visualization of the body region for review by the subject or another individual, such as a clinician.

[0056] calibration In one embodiment, the systems and methods disclosed herein can include components and methods for performing dynamic, real-time baseline processing or calibration of array data acquired by an array of sensors, such as, for example, a Cartesian array of capacitive and / or pressure sensors disclosed herein. In one embodiment, the system includes a set of capacitive and / or pressure sensors positioned on a surface and configured, for example, in a Cartesian configuration. The method can include periodically acquiring capacitive and / or pressure data from the set of sensors, for example, at a rate between 1 Hz and 1 kHz, or between 1 Hz and 500 Hz, or between 1 Hz and 100 Hz, or between 1 Hz and 30 Hz, or any suitable range. In one embodiment, the data acquired from the sensors is stored as a DC-shifted sparse matrix, where a portion of the data is within 1.5 standard deviations of the mean. In one embodiment, the majority or majority of the measured data is within 1.5 standard deviations of the mean.

[0057] A calibration method may include first collecting a predetermined amount of data and then calculating a baseline calibration point or "zero" point from the data, where all data falling outside one standard deviation from the mean of the data are removed from consideration, and a second mean is calculated from the subset of data falling within one standard deviation (SD) of the first mean. While the previous example uses one standard deviation from the mean as an illustrative threshold, it should be understood that in other embodiments, any suitable threshold may be used, including, without limitation, 0.3 SD, 0.5 SD, 0.75 SD, 0.8 SD, 0.9 SD, 1.1 SD, 1.25 SD, 1.5 SD, 2 SD, or the like. The second mean can then be used as the baseline or zero point for the remaining data. As a result, the second average is considered as an offset for all remaining data, and the second average is subtracted for each measured data point, resulting in the majority of the data being at or near the new zero point (i.e., the second average), thereby allowing outlier data from the full set of measured data to be appropriately highlighted.

[0058] In some embodiments, several measurements are taken from all sensors before performing an initial calibration step, while in other embodiments, calibration is performed continuously, i.e., by performing calibration on the first set of measured data and repeating the calibration after each new set of measured data. This novel approach eliminates the need for the use of a conventional single static calibration, which can be inaccurate due to varying tissue stiffness between the tissue region used for calibration and the tissue in the measurement region. The method also prevents both inter- and intra-operator errors when a single calibration is performed incorrectly. For example, in some embodiments, an operator may apply varying pressures to the tissue between measurements or over the course of a single measurement, which would result in distorted data if static calibration were used. By dynamically calibrating the data as it is measured, the overall bias applied to the data can be adapted to properly distinguish true outliers from distortions produced by changing operator pressure.

[0059] In one embodiment, the calculated baseline level is used to verify and store the amount of measured data. In one example, a predetermined amount of data points are measured from at least one pressure or capacitance sensor configured as an array, such as a Cartesian array. In one embodiment, a moving average of the measured data points is calculated to smooth the data over time. The moving average can be calculated over a window of at least three samples, at least five samples, at least ten samples, at least twenty samples, or any suitable number of samples. The smoothed moving average data can then be monitored, and when the moving average moves within a specific range, a capture trigger can be activated to indicate that the captured data is now valid for measurement. In some embodiments, the specific range can be 40% to 60% of the dynamic measurement range of the sensor, or 45% to 55%, 47% to 53%, 49% to 51%, or approximately 50% of the dynamic measurement range of the sensor. Then, in some embodiments, once the capture trigger is activated, the data is monitored to see if it remains valid for a period of time, such as 2 seconds, 3 seconds, 5 seconds, etc. Then, when the data remains valid for the specified period of time, the smoothed and / or raw data measured in that interval is saved as a valid data measurement.

[0060] Visualizing sample data In some embodiments, and referring now to Figure 5, in addition to visualizing the body area, the visualization device may display some notification of the preliminary or actual screening determination. In some embodiments, the diagnostic device performs all data collection and processing, and the results are transmitted via a wired or wireless connection to a remote computing system or cloud system for processing and later visualization.

[0061] In some embodiments, the methods of the present invention may include one or more guided steps, such as notifications or prompts provided to the subject or clinician by the visualization or sensor device, that guide the subject through the self-screening. Such methods may include processing some or all of the data measured by the sensor device by a processor integrated within the device, by a processor integrated within the visualization device, or by a separate device located near or remote from the diagnostic device and diagnostic system having the visualization device. The guided steps may further include informing the subject or clinician of one or more operational steps to be performed on or by the device based on the processed data, such as, for example, moving up, moving down, moving left, moving right, applying a relatively strong pressure, applying a relatively light pressure, etc. Such self-screening systems allow subjects with no or minimal medical or device-related training to perform guided self-screening to gather data to be reviewed by a clinician.

[0062] In some embodiments, the graphic visualization may include or be updated based on the dynamic calibration methods disclosed above. In some embodiments, a 3D surface plot may be displayed by the interface of the present invention, in which the surface of the tissue being measured is displayed in the XY plane and the data is represented on the Z axis. As the baseline is updated, the XY surface of the data plot is offset vertically along the Z axis by subtracting the calculated baseline amount. Color coding of the surface is used to indicate deviations from the optimal baseline. When the baseline is within the optimal range, the surface appears green, except for deviations that gradually appear in yellow or red. As the baseline deviates from the optimal value, the surface transitions to yellow and eventually red, thereby indicating a significant deviation from the optimal baseline. Additionally, in some embodiments, the calibration display graphically depicts the calculated baseline itself on the screen, providing further feedback to the operator, allowing the operator to adjust (for example) their applied pressure to move the baseline within the optimal range. This novel visualization method optimizes user training by promoting the capture of consistent baselines and maximizing measurement completeness.

[0063] An example is shown with reference to Figures 6A, 6B, and 6C. As shown in Figure 6A, an uncalibrated surface map can show most points in red, i.e., deviations from a fixed "zero" value. In the example shown, most points in the surface map measure around 22%, which is significantly less than the fixed zero value of 50%. Therefore, these points are all highlighted in red as deviations from the zero value.

[0064] Figure 6B shows a visualization of the dynamically calibrated data. The data map shown in Figure 6B shows the entire surface in green, i.e., normal. The data has been calibrated to remove offset and is therefore mostly contained within the green window, which in the illustrated embodiment is 55%-65%.

[0065] Figure 6C shows a visualization of data approaching optimal real-time calibration. While most of the graph is shown in green, some of the surface is yellow-green, signaling that some of the data still falls outside the zero window. The average of the depicted data is approximately 44%, which falls just outside the optimal window of 45%-55%.

[0066] An exemplary method for measuring a tissue parameter within a subject is shown in Figure 7. The method includes positioning a handheld device having a plurality of electrodes and a predetermined amount of non-conductive compressible material and covering substantially in contact with a body region of the subject in step 701, measuring a capacitance between two electrodes of the plurality of electrodes in step 702, determining a thickness of the flexible material based on the capacitance in step 703, and calculating a tissue parameter based on the thickness of the flexible material in step 704.

[0067] According to one embodiment, a capacitive touch sensor device for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of skin or other soft tissue within a subject by measuring variations in tactile pressure on the skin or other tissue surface includes a housing having at least one exposed window and an exposed conductive surface positioned to be in constant contact with the conductive surface while an operator or the device is operating the device. Disposed within the housing is a substrate having a plurality of separate, coplanar, co-located electrode pairs configured as a Cartesian grid on an electrically non-conductive material and configured such that any two adjacent electrodes are electrically independent and can be independently stimulated by an externally generated stimulation voltage or current signal, thereby creating a capacitor between each such electrode pair, with the space on the outer-facing surface of the electrode grid acting as a dielectric. A layer of insulating material is positioned on the outer-facing surface of the electrode grid. A homogeneous, compressible, non-ferrite, and non-conductive membrane covering the insulating layer is positioned on the outward-facing surface of the electrode grid, the membrane (a) having a uniform thickness across the entire surface area of ​​each pair of adjacent electrodes forming a capacitor and across the entire surface area of ​​the Cartesian grid of electrodes, (b) having a fixed, uniform, and known compression ratio and hardness across the entire surface area of ​​the Cartesian grid of electrodes, and (c) having a steady-state equilibrium shape such that its volume remains constant when no external force is applied. A non-conductive cover material is positioned on the outward-facing surface of the homogeneous, compressible, non-ferrite, and compressible membrane, at least a portion of which is accessible through an exposure window in the housing, which serves as the outward-facing surface of the sensor and, together with the membrane, effectively replaces air as a dielectric for the capacitor created by each pair of adjacent electrodes, one functioning as a transmitting electrode and one functioning as a receiving electrode.The sensor surface is configured to be placed completely and firmly in contact with the surface of the subject's tissue such that electromechanical properties, including normal surface pressure, of the conductive tissue disrupt the electric field within the dielectric comprised of the compressible membrane and disrupt capacitive coupling between associated pairs of coplanar electrodes, wherein the sensor input device induces and generates at least one signal in response to pressure applied on the sensor surface by contact with the skin or other soft tissue surface and the resulting compression of the compressible membrane and disruption of capacitive coupling between associated pairs of coplanar electrodes in accordance with the changing composition and properties of the underlying tissue structure as an indicator of the location, mechanics, and specific characteristics of the localized area of ​​relatively rigid tissue underlying the area of ​​the skin or other tissue surface being investigated. (a) one or more commercially available IC capacitive sensor chips configured to (i) generate signals used to stimulate electrode pairs disposed within the substrate, (ii) receive and process signals subsequently induced, generated, and transmitted by the capacitive tactile sensor input device in response to pressure applied on the sensor surface by contact with the skin or other soft tissue surface, and (iii) induce, generate, and transmit to the device signals derived from processing the signals induced, generated, and transmitted by the capacitive tactile sensor input device to the one or more IC capacitive sensor chips; and (b) a controller comprising one or more integrated circuits and a processor configured to (i) receive and process the signals induced, generated, and transmitted by the one or more IC capacitive sensor chips to calculate one or more parameters of the underlying tissue structure based on changes in perceived capacitance between adjacent associated electrode pairs generated by pressure applied on the sensor surface by contact with the skin or other soft tissue surface, and (ii) communicatively connect to a visualization device having a display and integrated storage device.

[0068] In one embodiment, the homogeneous compressible non-ferrite and non-conductive membrane comprises a polyurethane, silicone, or thermoplastic elastomer foam. In one embodiment, the foam has a hardness ranging from 00-0 to 00-20. In one embodiment, the plurality of electrodes comprises at least two electrodes. In one embodiment, each of the plurality of electrodes is 1 mm thick. 2 ~16mm 2 In one embodiment, the device includes a visualization device communicatively connected to the controller, where the visualization device has a display. In one embodiment, the controller is connected to the visualization device via a Bluetooth® connection. In one embodiment, the device includes a conductive element on the exterior of the housing configured to provide a voltage reference used for all subsequent capacitive calculations. In one embodiment, the device includes a grounding pad or strap that provides conductive contact between an uninsulated portion of an electrode plane configured to provide a voltage reference used for all subsequent capacitive calculations and the exterior surface of the capacitive sensor. In one embodiment, the at least one parameter includes tissue stiffness. In one embodiment, the subject's tissue includes breast tissue.

[0069] In one embodiment, a method for documenting, measuring, and mapping the size, shape, and location of underlying palpable lesions on the skin or other soft tissue surface within a subject using capacitive tactile sensing to measure variations in normal tactile pressure on the surface of the skin or other soft tissue surface of the tissue includes the steps of positioning a handheld device having a plurality of electrodes and a predetermined amount of non-conductive compressible material and covering in substantial contact with the skin or tissue surface area of ​​the subject; determining a baseline reference capacitance of the subject by measurements taken by an operator from a lesion-free area of ​​the tissue; determining a baseline potential reference from the operator through conductive contact between the operator and the handheld device; and The method includes the steps of: positioning a sensor device in substantial contact with the surface area of ​​the skin or tissue being investigated; measuring a capacitance between two electrodes of the plurality of electrodes resulting from contact with the surface area of ​​the skin or tissue being investigated; measuring a variation in perceived capacitance between adjacent associated electrode pairs with reference to a baseline potential reference created by pressure applied to the sensor surface (compressible membrane and covering) resulting from a disruption to the capacitive coupling between adjacent associated electrode pairs created by contact with the skin or surface of the tissue being investigated; and calculating one or more tissue parameters based on the variation in perceived capacitance from the baseline potential reference. In one embodiment, the method includes transmitting data selected from the group consisting of perceived capacitance, thickness, and tissue parameters to a visualization system. In one embodiment, the method includes measuring a plurality of capacitance values ​​between the set of electrode pairs and displaying a diagram of the parameter values ​​across the tissue surface on the visualization system. In one embodiment, the tissue parameter is stiffness.

[0070] In one embodiment, a method for performing an inductive self-test on a subject's tissue includes positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of the subject, measuring a capacitance between two of the plurality of electrodes, calculating a tissue parameter based on the capacitance, determining in a controller instructions for the subject based on the tissue parameter, and issuing the instructions to the subject to guide them to operate the handheld device. In one embodiment, the instructions are auditory instructions issued through a speaker. In one embodiment, the instructions are configured to guide the subject to move the device to a new location on the tissue. In one embodiment, the instructions include visual cues presented on a display.

[0071] Experimental example The present invention will be described in further detail with reference to the following experimental examples. These examples are provided for illustrative purposes only and, unless otherwise specified, are not intended to be limiting. Therefore, the present invention should in no way be construed as being limited to the following examples, but rather as embracing any and all variations that become evident as a result of the teachings provided herein.

[0072] Without further description, it is believed that one skilled in the art can, using the foregoing description and the following illustrative examples, make and use the systems and methods of the present invention. Accordingly, the following examples specifically point out example embodiments of the present invention, and are not to be construed as limiting in any way the remainder of the disclosure.

[0073] Referring to FIG. 8, sample compression data for a piezoelectric versus capacitive sensor is provided according to one embodiment.

[0074] The disclosures of each and every patent, patent application, and publication cited herein are hereby incorporated by reference in their entirety. While the present invention has been disclosed with reference to specific embodiments, it will be apparent that other embodiments and modifications of the present invention may be devised by those skilled in the art without departing from the true spirit and scope of the present invention. It is intended that the appended claims be construed to cover all such embodiments and equivalent variations. Some aspects of the invention are described below. [Aspect 1] 1. An apparatus for measuring a tissue parameter within a subject, comprising: a housing having at least one exposure window; a substrate having a plurality of electrodes disposed within the housing; an insulating layer positioned over the electrodes; a flexible membrane positioned on the insulating layer, at least a portion of the flexible membrane being accessible through the exposure window; a controller disposed within the housing configured to calculate at least one parameter of the subject's tissue based on the capacitance measured between the electrodes; and A device having: [Aspect 2] 10. The apparatus of claim 1, wherein the flexible membrane comprises foam. [Aspect 3] 3. The device according to embodiment 2, wherein the foam has a hardness ranging from 00-0 to 00-20. [Aspect 4] The device of embodiment 1, wherein the plurality of electrodes comprises at least two electrodes. [Aspect 5] 2. The device of embodiment 1, wherein each of the plurality of electrodes has a surface area of ​​1 mm 2 to 16 mm 2 . [Aspect 6] The apparatus of embodiment 1, further comprising a visualization device communicatively connected to the controller, the visualization device comprising a display. [Aspect 7] The apparatus of embodiment 6, wherein the controller is connected to the visualization device via a Bluetooth® connection. [Aspect 8] 10. The device of embodiment 1, further comprising a conductive element configured to provide a voltage reference to a surface in contact with the flexible membrane. [Aspect 9] 9. The apparatus of claim 8, wherein the conductive element is positioned to substantially surround the exposure window. [Aspect 10] The apparatus of embodiment 1, wherein the at least one parameter comprises tissue stiffness. [Aspect 11] The apparatus of claim 1, wherein the tissue of the subject comprises breast tissue. [Aspect 12] 1. A method for measuring a tissue parameter within a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; determining a thickness of the flexible material based on the capacitance; calculating a tissue parameter based on the thickness of the pliant material; A method having the following. [Aspect 13] 13. The method of claim 12, further comprising transmitting data selected from the group consisting of the capacitance, the thickness, and the tissue parameter to a visualization system. [Aspect 14] measuring a plurality of capacitance values ​​between a set of electrode pairs; displaying a plot of parameter values ​​across the tissue surface on the visualization system; 14. The method of embodiment 13, further comprising: [Aspect 15] 13. The method of claim 12, wherein the tissue parameter is stiffness. [Aspect 16] 13. The method of embodiment 12, further comprising performing a provisional diagnosis based on the tissue parameters. [Aspect 17] 1. A method for performing guided self-testing on tissue of a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; calculating a tissue parameter based on the capacitance; determining, in a controller, instructions for the subject based on the tissue parameters; issuing the instructions to the subject to guide the subject to operate the handheld device; A method having the following. [Aspect 18] 18. The method of claim 17, wherein the command is an audible command issued through a speaker. [Aspect 19] 18. The method of claim 17, wherein the instructions are configured to guide the subject to move the device to a new location on the tissue. [Aspect 20] 18. The method of claim 17, wherein the instructions include a visual cue presented on a display. [Aspect 21] 1. A capacitive tactile sensor device for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on the surface of skin or other soft tissue within a subject by measuring variations in tactile pressure on said surface; a housing having at least one exposed window and an exposed conductive surface positioned so that an operator or the device is in constant contact with the conductive surface while the device is operating; a substrate disposed within the housing having a plurality of pairs of separate, coplanar, co-located electrodes configured as a Cartesian grid on an electrically non-conductive material and configured such that any two adjacent electrodes are independent and can be independently stimulated by an externally generated stimulation voltage or current signal, thereby creating a capacitor between each such electrode pair, with the space above the outwardly facing surface of the electrode grid acting as a dielectric; a layer of insulating material positioned on the outer-facing surface of the electrode grid; a homogeneous compressible non-ferrite and non-conductive membrane covering the insulating layer positioned on the outwardly facing surface of the electrode grid, the membrane (a) having a uniform thickness across the entire surface area of ​​each pair of adjacent electrodes forming a capacitor and across the entire surface area of ​​the Cartesian grid of electrodes, (b) having a fixed, uniform and known compression ratio and hardness across the entire surface area of ​​the Cartesian grid of electrodes, and (c) having a steady-state equilibrium shape such that its volume remains constant when no external force is applied; a non-conductive cover material positioned on the outwardly facing surface of the homogeneous compressible non-ferrite and compressible membrane, at least a portion of which is accessible through the exposure window of the housing, which serves as the outwardly facing surface of the sensor and, together with the membrane, effectively replaces air as a dielectric for a capacitor created by each pair of adjacent electrodes, one serving as the transmitting electrode and one serving as the receiving electrode; the sensor surface is configured to be placed completely and firmly in contact with the surface of the tissue of the subject such that the electromechanical properties, including the normal surface pressure of the conductive tissue, disrupt the electric field within the dielectric formed by the compressible membrane and disrupt the capacitive coupling between an associated pair of the coplanar electrodes; a non-conductive cover material, the sensor input device inducing and generating at least one signal in response to pressure applied to the sensor surface by contact with the skin or other soft tissue surface and the resulting compression of the compressible membrane and disruption of the capacitive coupling between an associated pair of the coplanar electrodes as an indicator of the location, mechanics, and specific characteristics of a localized area of ​​relatively rigid tissue underlying the area of ​​skin or other tissue surface being interrogated in accordance with the changing composition and properties of the underlying tissue structure; (a) one or more commercially available IC capacitive sensor chips configured to (ii) generate signals used to stimulate the electrode pairs disposed within the substrate; (ii) receive and process the signals subsequently induced, generated, and transmitted by the capacitive tactile sensor input device in response to the pressure applied to the sensor surface by contact with the skin or other soft tissue surface; and (iii) induce, generate, and transmit to the one or more IC capacitive sensor chips signals derived from the processing of the signals induced, generated, and transmitted by the capacitive tactile sensor input device to the one or more IC capacitive sensor chips. and (b) a controller disposed within the housing comprising one or more integrated circuits and a processor configured to (i) receive and process the signals induced, generated, and transmitted by the one or more IC capacitive sensor chips to calculate one or more parameters of the underlying tissue structure based on changes in the perceived capacitance between the adjacent associated electrode pairs produced by the pressure applied against the sensor surface by contact with the skin or other soft tissue surface, and (ii) communicatively couple to a visualization device having a display and integrated storage device. A device having: [Aspect 22] 22. The apparatus of claim 21, wherein the homogeneous compressible non-ferrite and non-conductive membrane comprises polyurethane, silicone, or thermoplastic elastomer foam. [Aspect 23] 23. The device according to embodiment 22, wherein the foam has a hardness ranging from 00-0 to 00-20. [Aspect 24] 22. The apparatus of claim 21, wherein the plurality of electrodes comprises at least two electrodes. [Aspect 25] 22. The device according to embodiment 21, wherein each of the plurality of electrodes has a surface area of ​​1 mm 2 to 16 mm 2 . [Aspect 26] 22. The apparatus of claim 21, further comprising a visualization device communicatively connected to the controller, the visualization device comprising a display. [Aspect 27] 27. The apparatus of claim 26, wherein the controller is connected to the visualization device via a Bluetooth connection. [Aspect 28] 22. The apparatus of claim 21, further comprising a conductive element external to the housing configured to provide a voltage reference used for all subsequent capacitive calculations. [Aspect 29] The apparatus of embodiment 21 includes a grounding pad or strip that provides conductive contact between the uninsulated portion of the electrode plane and the external surface of the capacitive sensor, configured to supply a voltage reference used for all subsequent capacitive calculations. [Aspect 30] 22. The apparatus of claim 21, wherein the at least one parameter comprises tissue stiffness. [Aspect 31] 22. The apparatus of claim 21, wherein the tissue of the subject comprises breast tissue. [Aspect 32] 1. A method for documenting, measuring, and mapping the size, shape, and location of a palpable lesion underlying the surface of skin or other soft tissue area within a subject by measuring normal tactile pressure variations on the surface of said skin or other soft tissue area of ​​said tissue surface using capacitive tactile sensing, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of non-conductive compressible material and covering substantially in contact with the surface area of ​​the skin or tissue of the subject; determining a baseline reference capacitance of the subject from measurements taken by the operator from an unlesioned area of ​​tissue; determining a baseline potential reference from the operator through conductive contact between the operator and the handheld device; positioning the handheld device substantially in contact with the surface area of ​​the skin or tissue being investigated; measuring a capacitance between two electrodes of the plurality of electrodes resulting from contact with the surface area of ​​the skin or tissue being investigated; measuring the variation in perceived capacitance between the adjacent associated electrode pairs with reference to the baseline potential reference generated by pressure applied to the sensor surface (compressible membrane and covering) resulting from a perturbation to the capacitive coupling between the adjacent associated electrode pairs caused by contact with the skin or tissue surface of the tissue being investigated; calculating one or more tissue parameters based on the variation in the perceived capacitance from the baseline potential reference; A method having the following. [Aspect 33] 33. The method of claim 32, further comprising transmitting data selected from the group consisting of the perceived capacitance, the thickness, and the tissue parameter to a visualization system. [Aspect 34] A method according to aspect 33, further comprising measuring a plurality of capacitance values ​​between a set of electrode pairs and displaying a diagram of parameter values ​​across the tissue surface on the visualization system. [Aspect 35] 33. The method of claim 32, wherein the tissue parameter is stiffness. [Aspect 36] The method of embodiment 32, utilizing the device of embodiment 31. [Aspect 37] 1. A method for performing guided self-testing on tissue of a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; calculating a tissue parameter based on the capacitance; determining, in a controller, instructions for the subject based on the tissue parameters; issuing the command to the subject to guide the subject to operate the handheld device; A method having the following. [Aspect 38] 38. The method of claim 37, wherein the command is an audible command issued through a speaker. [Aspect 39] 38. The method of claim 37, wherein the instructions are configured to guide the subject to move the device to a new location on the tissue. [Aspect 40] 38. The method of embodiment 37, wherein the instructions include a visual cue presented on a display. [Aspect 41] 1. A method for dynamically calibrating data received from at least one sensor, comprising: acquiring a plurality of data values ​​from at least one sensor; calculating a first mean and a first standard deviation of the plurality of data values; obtaining a subset of the plurality of data values ​​whose values ​​are within one standard deviation of the first mean; calculating a second average from the subset of the plurality of data values ​​as a baseline value; subtracting the baseline value from the plurality of data values ​​to generate a calibrated data set; A method having the following. [Aspect 42] obtaining a second plurality of data values; calculating a third mean and a third standard deviation of the first and second pluralities of data values; obtaining a second subset of the first and second pluralities of data values ​​whose values ​​are within one standard deviation of the third mean; calculating a fourth average from the second subset of the plurality of data values ​​as a second baseline value; subtracting the second baseline value from the first and second plurality of data values ​​to generate the calibrated data set; 42. The method of embodiment 41, further comprising: [Aspect 43] displaying a three-dimensional surface plot of the calibrated data set; displaying the baseline value; providing visual feedback when the baseline value is within an optimal range; 42. The method of embodiment 41, further comprising: [Aspect 44] 44. The method of claim 43, wherein the visual feedback comprises changing the color of an area of ​​the three-dimensional surface plot. [Aspect 45] calculating a moving average of the plurality of data values; calculating the first mean and the first standard deviation from the moving average; 42. The method of embodiment 41, further comprising: [Aspect 46] comparing the moving average to maximum and minimum thresholds; capturing the plurality of data values ​​or the moving average when the moving average is between the maximum and minimum thresholds; storing the captured data values ​​on a non-transitory computer readable medium when the moving average remains between the maximum and minimum thresholds for a defined period of time; 46. ​​The method of embodiment 45, further comprising: [Aspect 47] 47. The method of claim 46, wherein the defined period is at least 3 seconds.

Claims

1. 1. An apparatus for measuring a tissue parameter within a subject, comprising: a housing having at least one exposure window; a substrate having a plurality of electrodes disposed within the housing; an insulating layer positioned over the plurality of electrodes; a flexible membrane positioned on the insulating layer, at least a portion of the flexible membrane being accessible through the exposure window; a controller disposed within the housing configured to calculate at least one parameter of tissue of the subject based on capacitance measured between the plurality of electrodes; and The at least one parameter is indicative of tissue stiffness.

2. The device of claim 1 , wherein the flexible membrane comprises foam.

3. 3. The device of claim 2, wherein the foam has a Shore hardness ranging from 00-0 to 00-20.

4. The device of claim 1 , wherein the plurality of electrodes comprises at least two electrodes.

5. Each of the plurality of electrodes is 1 mm ２ ~16mm ２ 10. The device of claim 1 having a surface area of

6. The apparatus of claim 1 , further comprising a visualization device communicatively connected to the controller, the visualization device comprising a display.

7. The device of claim 6 , wherein the controller is connected to the visualization device via a Bluetooth connection.

8. 10. The apparatus of claim 1, further comprising a conductive element configured to provide a voltage reference to a surface in contact with the flexible membrane.

9. 9. The apparatus of claim 8, wherein the conductive element is positioned to substantially surround the exposure window.

10. The apparatus of claim 1 , wherein the tissue of the subject comprises breast tissue.

11. 1. A method for measuring a tissue parameter within a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; determining a thickness of the flexible material based on the capacitance; calculating the tissue parameter based on the thickness of the pliant material; and The method, wherein the texture parameter is hardness.

12. 12. The method of claim 11, further comprising transmitting data selected from the group consisting of the capacitance, the thickness, and the tissue parameter to a visualization system.

13. measuring a plurality of capacitance values ​​between a set of electrode pairs; displaying on the visualization system a diagram of parameter values ​​across a tissue surface of the subject's body region; 13. The method of claim 12 further comprising:

14. The method of claim 11 , further comprising the step of performing a provisional diagnosis based on the tissue parameters.

15. 1. A method for performing guided self-testing on tissue of a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; calculating a tissue parameter indicative of a stiffness of the tissue of the subject based on the capacitance; determining, in a controller, instructions for the subject based on the tissue parameters; issuing the instructions to the subject to guide the subject to operate the handheld device; A method having the following.

16. 16. The method of claim 15, wherein the command is an audible command issued through a speaker.

17. 16. The method of claim 15, wherein the instructions are configured to guide the subject to move the handheld device to a new location on the tissue.

18. 16. The method of claim 15, wherein the instructions comprise visual cues presented on a display.

19. 1. A capacitive tactile sensor device for detecting, documenting, measuring, and mapping the size, shape, and location of underlying lesions on a surface of a subject's skin tissue or soft tissue by measuring variations in tactile pressure on the surface of the subject's skin tissue or soft tissue, comprising: a housing having at least one exposed window and an exposed conductive surface positioned to be in contact with the surface of the skin tissue or soft tissue at all times while an operator or the capacitive tactile sensor device is operating the capacitive tactile sensor device; a substrate disposed within the housing having an electrode grid having a plurality of separate, coplanar, co-located electrode pairs configured as a Cartesian grid on an electrically non-conductive material, wherein any two adjacent electrodes of the plurality of electrode pairs are independent and capable of being independently stimulated by an externally generated stimulation voltage or current signal, thereby creating a capacitance between each of the electrode pairs, with the space above the outwardly facing surface of the electrode grid acting as a dielectric; and a layer of insulating material positioned on the outer-facing surface of the electrode grid; a homogeneous compressible non-ferrite and non-conductive membrane covering the layer of insulating material positioned on the outwardly facing surface of the electrode grid, the membrane (a) having a uniform thickness across the entire surface area of ​​each pair of adjacent electrodes that form the capacitor and across the entire surface area of ​​the electrode grid, (b) having a fixed, uniform and known compression ratio and hardness across the entire surface area of ​​the electrode grid, and (c) having a steady-state equilibrium shape such that the volume of the membrane remains constant when no external force is applied; a non-conductive cover material positioned on an outwardly facing surface of the homogeneous non-ferrite and compressible membrane, at least a portion of which is accessible through the exposure window of the housing, which serves as an outwardly facing surface of the capacitive touch sensor device and, together with the membrane, effectively replaces air as a dielectric for a capacitor created by each pair of adjacent electrodes, one functioning as a transmitting electrode and one functioning as a receiving electrode; the outer-facing surface of the capacitive touch sensor device is configured to be placed completely and firmly in contact with the surface of the skin tissue or soft tissue of the subject such that electromechanical properties, including normal surface pressure, of the skin tissue or soft tissue disrupt the electric field within the dielectric formed by the compressible membrane and prevent capacitive coupling between each pair of adjacent coplanar electrodes; a non-conductive cover material, wherein the capacitive tactile sensor device induces and generates at least one signal in response to pressure applied to the outwardly facing surface of the capacitive tactile sensor device by contact with the surface of the skin tissue or soft tissue and the resulting compression of the compressible membrane and disruption of the capacitive coupling between each pair of adjacent coplanar electrodes as an indicator of the location, mechanics, and specific characteristics of a localized area of ​​relatively rigid tissue underlying the surface area of ​​the skin tissue or soft tissue being investigated in accordance with the changing composition and properties of the underlying tissue structure; (a) one or more commercially available IC capacitive sensor chips configured to (i) generate signals used to stimulate respective pairs of adjacent electrodes disposed within the substrate; (ii) receive and process signals subsequently induced, generated, and transmitted by the capacitive tactile sensor device in response to the pressure applied against the outwardly facing surface by contact of the skin tissue or soft tissue surface with the surface; and (iii) induce, generate, and transmit to the capacitive tactile sensor device signals derived from the processing of the signals induced, generated, and transmitted by the capacitive tactile sensor device to the one or more IC capacitive sensor chips. and (b) a controller disposed within the housing, comprising one or more integrated circuits and a processor, configured to (i) receive and process the signals induced, generated, and transmitted by the one or more IC capacitive sensor chips to calculate one or more parameters of the underlying tissue structure based on changes in capacitance perceived between each pair of adjacent electrodes generated by the pressure applied to the outer-facing surface of the capacitive touch sensor device by contact with the surface of the skin tissue or the soft tissue, and (ii) communicatively connect with a visualization device having a display and integrated storage device. and The apparatus wherein at least one of the parameters is indicative of stiffness of the skin tissue or the soft tissue.

20. 20. The device of claim 19, wherein the homogeneous compressible non-ferrite and non-conductive membrane comprises polyurethane, silicone, or thermoplastic elastomer foam.

21. 21. The device of claim 20, wherein the polyurethane, silicone, or thermoplastic elastomer foam has a Shore hardness ranging from 00-0 to 00-20.

22. 20. The apparatus of claim 19, wherein the plurality of electrode pairs comprises at least two electrodes.

23. Each electrode of the plurality of electrode pairs has a length of 1 mm ２ ~16mm ２ 20. The device of claim 19 having a surface area of

24. 20. The apparatus of claim 19, further comprising a visualization device communicatively connected to the controller, the visualization device comprising a display.

25. 25. The device of claim 24, wherein the controller is connected to the visualization device via a Bluetooth connection.

26. 20. The apparatus of claim 19, further comprising a conductive element external to the housing configured to provide a voltage reference used for all subsequent capacitive calculations.

27. 20. The device of claim 19, including a grounding pad or strip that provides conductive contact between the uninsulated portion of the electrode plane and the exterior surface of the capacitive touch sensor device, configured to provide a voltage reference used for all subsequent capacitive calculations.

28. 20. The apparatus of claim 19, wherein the tissue of the subject comprises breast tissue.

29. 1. A method for documenting, measuring, and mapping the size, shape, and location of a palpable lesion underlying a surface area of ​​skin tissue or soft tissue of a subject by measuring normal tactile pressure variations over said surface area of ​​said skin tissue or soft tissue using capacitive tactile sensing, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of non-conductive compressible material and covering substantially in contact with the surface area of ​​the skin tissue or soft tissue of the subject; determining a baseline reference capacitance of the subject from measurements taken by an operator from an unlesioned area of ​​tissue; determining a baseline potential reference from the operator through conductive contact between the operator and the handheld device; positioning the handheld device substantially in contact with the surface area of ​​the skin tissue or soft tissue being investigated; measuring a capacitance between two electrodes of the plurality of electrodes resulting from contact with the surface area of ​​the skin tissue or soft tissue being investigated; measuring a variation in perceived capacitance between the two electrodes with reference to the baseline potential reference generated by pressure applied against a surface of a compressible membrane of the handheld device in contact with the surface area of ​​the skin tissue or soft tissue being investigated resulting from a disruption to the capacitive coupling between the two electrodes caused by contact with the surface area of ​​the skin tissue or soft tissue being investigated; calculating one or more tissue parameters based on the variation in the perceived capacitance from the baseline potential reference; and The method, wherein the texture parameter indicates hardness.

30. 30. The method of claim 29, further comprising transmitting data selected from the group consisting of the perceived capacitance and the tissue parameters to a visualization system.

31. 31. The method of claim 30, further comprising measuring a plurality of capacitance values ​​between a set of electrode pairs and displaying a diagram of parameter values ​​across the surface area of ​​the skin tissue or soft tissue on the visualization system.

32. 30. The method of claim 29, utilizing the apparatus of claim 28.

33. 1. A method for performing guided self-testing on tissue of a subject, comprising: positioning a handheld device having a plurality of electrodes and a predetermined amount of flexible material substantially in contact with a body region of a subject; measuring a capacitance between two electrodes of the plurality of electrodes; calculating a tissue parameter based on the capacitance; determining, in a controller, instructions for the subject based on the tissue parameters; issuing the command to the subject to guide the subject to operate the handheld device; and The method, wherein the texture parameter indicates hardness.

34. 34. The method of claim 33, wherein the command is an audible command issued through a speaker.

35. 34. The method of claim 33, wherein the instructions are configured to direct the subject to move the handheld device to a new location on the tissue.

36. 34. The method of claim 33, wherein the instructions comprise visual cues presented on a display.

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