Patent Application
20150177256
This application generally relates to the field of blood analyte meters and more specifically to portable blood glucose meters that are equipped to magnify a test strip used in conjunction with the meter so that users may clearly view sample application onto the test strip.
Blood glucose measurement systems typically comprise an analyte meter that is configured to receive a biosensor, usually in the form of a test strip. Because many of these systems are portable, and testing can be completed in a short amount of time, patients are able to use such devices almost anywhere during the normal course of their daily lives without significant interruption to their personal routines. A person with diabetes may measure their blood glucose levels several times a day as a part of a self management process to ensure glycemic control of their blood glucose within a target range. A failure to maintain target glycemic control can result in serious diabetes-related complications including cardiovascular disease, kidney disease, nerve damage and blindness.
There currently exist a number of available portable electronic devices that can measure glucose levels in an individual based on a small sample of blood applied to a small glucose test strip. To provide the sample, a person is required to prick their finger in order to apply the blood sample onto the test strip using a lancet or similar implement. Due to the economics of test strip fabrication and many users' desire for reduced-dimension devices, the test strips may be fairly small and difficult to see for some users and, in other cases, the visual acuity of the subjects themselves may create an impediment to reliable or sufficient sample application. It would be advantageous to provide glucose test meters with features to enable users to clearly view the sample chamber on a test strip for purposes of application.
The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain features of the invention (wherein like numerals represent like elements).
The following detailed description should be read with reference to the drawings, in which like elements in different drawings are identically numbered. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. The detailed description illustrates by way of example, not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.
As used herein, the terms “patient” or “user” refer to any human or animal subject and are not intended to limit the systems or methods to human use, although use of the subject invention in a human patient represents a preferred embodiment.
The term “sample” means a volume of a liquid, solution or suspension, intended to be subjected to qualitative or quantitative determination of any of its properties, such as the presence or absence of a component, the concentration of a component, e.g., an analyte, etc. The embodiments of the present invention are applicable to human and animal samples of whole blood. Typical samples in the context of the present invention as described herein include blood, plasma, red blood cells, serum and suspension thereof.
The term “about” as used in connection with a numerical value throughout the description and claims denotes an interval of accuracy, familiar and acceptable to a person skilled in the art. The interval governing this term is preferably +10%. Unless specified, the terms described above are not intended to narrow the scope of the invention as described herein and according to the claims.
In brief, the system disclosed herein includes a test meter that employs a camera and an illumination source to provide a live video image of a test strip to allow for easier blood sample application onto the test strip. The test meter is activated by detecting insertion of the test trip into a test strip port of the meter. In one embodiment, the meter is placed in a video capture mode by moving at least the camera, or the camera and a display screen, into a predetermined position. The user then views the test strip on the display screen while applying a sample. The invention described herein is equally applicable to patients with other conditions requiring regular self-monitoring of analytes in biological fluids other than glucose.
With reference to
Specifically, and according to this exemplary embodiment, the user interface buttons 16 include markings, e.g., up-down arrows, text characters “OK”, etc, which allow a user to navigate through the user interface presented on the display 14. Although the buttons 16 are shown herein as separate switches, a touch screen interface on display 14 with virtual buttons may also be utilized. As discussed herein, the display 14 may comprise a movable type of display, such as a sliding display (
The electronic components of the glucose measurement system 100 can be disposed on, for example, a printed circuit board situated within the housing 11 and forming the data management unit 150 of the herein described system.
The processing unit 50 may be electrically connected to the test strip port connector (“SPC”) circuit 70 positioned in the test strip port 22 via an analog front end sub-system 72. The analog front end 72 is electrically connected to the SPC 70 during blood glucose testing. To measure a selected analyte concentration, the SPC 70 is configured to detect a resistance or impedance across electrodes of the analyte test strip 24 having a blood sample disposed in the sample chamber 34 therein, using a potentiostat, and converts an electric current measurement into digital form for presentation on the display 14, typically in units of mg/dL. The processing unit 50 can be configured to receive input from the SPC 70 via analog front end circuit 72 over an interface 71 and may also perform a portion of the potentiostat function and the current measurement function.
The test strip 24 can be in the form of an electrochemical test strip for measuring a glucose concentration, or other analyte appropriate for monitoring of a biological condition. The test strip 24 is defined by one or more nonporous non-conducting substrates, or layers, onto which one or more electrodes, or conductive coatings may be deposited. These electrodes may function as working electrodes, reference electrodes, counter electrodes or combined counter/reference electrodes. Additional non-conducting layers may be applied in order to define the planar dimensions of the electrode structure(s). Test strip 24 can also include a plurality of electrical contact pads, where each electrode can be in electrical communication with at least one electrical contact pad. SPC 70 can be configured to electrically interface to the electrical contact pads and form electrical communication with the electrodes. Test strip 24 can include a reagent layer that is disposed over at least one electrode forming part of an electrochemical cell of the test strip 24, including the working electrode. The reagent layer can include an enzyme and a mediator. Exemplary enzymes suitable for use in the reagent layer include glucose oxidase, glucose dehydrogenase (with pyrroloquinoline quinone co-factor, “PQQ”), and glucose dehydrogenase (with flavin adenine dinucleotide co-factor, “FAD”). Enzymes other than those used to determine glucose are also applicable, for example, lactate dehydrogenase for lactate, β-hydroxybutyrate dehydrogenase for β-hydroxybutyrate (ketone body). An exemplary mediator suitable for use in the reagent layer includes ferricyanide, which in this case is in the oxidized form. Other mediators may be equally applicable, depending upon the desired strip operating characteristics, for example, ferrocene, quinone or osmium-based mediators. The reagent layer can be configured to physically transform glucose into an enzymatic by-product and in the process generate an amount of reduced mediator (e.g., ferrocyanide) that is proportional to the glucose concentration. The working electrode can then be used to measure a concentration of the reduced mediator in the form of a current magnitude. In turn, microcontroller 50 can convert the current magnitude into a glucose concentration. An exemplary analyte meter performing such current measurements is described in U.S. Patent Application Publication No. US 2009/0301899 A1 entitled “System and Method for Measuring an Analyte in a Sample”, which is incorporated by reference herein as if fully set forth in this application.
A display module 58, which may include a display processor and display buffer, is electrically connected to the processing unit 50 over the communication interface 57 for receiving and displaying output data, and for displaying user interface input options under control of the processing unit 50. The display interface is accessible via the processing unit 50 for presenting menu options to a user of the blood glucose measurement system 100. User input module 64 may receive responsive inputs from the user manipulating buttons, or keypad 16, which are processed and transmitted to the processing unit 50 over the communication interface 63. The processing unit 50 may have electrical access to a digital time-of-day clock connected to the printed circuit board for recording dates and times of blood glucose measurements and user inputs, which may then be accessed, uploaded, or displayed at a later time as necessary.
An on-board memory module 62, that includes but is not limited to volatile random access memory (“RAM”), a non-volatile memory, which may comprise read only memory (“ROM”) or flash memory, and may be connected to an external portable memory device via a data port 13, is electrically connected to the processing unit 50 over a communication interface 61. External memory devices may include flash memory devices housed in thumb drives, portable hard disk drives, data cards, or any other form of electronic storage device. The on-board memory can include various embedded applications executed by the processing unit 50 for operation of the analyte meter 10, as explained herein. On board or external memory can also be used to store a history of a user's blood glucose measurements including dates and times associated therewith. Using the wireless transmission capability of the analyte meter 10, or the data port 13, as described herein, such measurement data can be transferred via wired or wireless transmission to connected computers or other processing devices.
A communications module 60 may include transceiver circuits for wireless digital data transmission and reception, and is electrically connected to the processing unit 50 over communication interface 59. The wireless transceiver circuits may be in the form of integrated circuit chips, chipsets, and programmable functions operable via processing unit 50 using on-board memory, or a combination thereof. The wireless transceiver circuits may be compatible with different wireless transmission standards. For example, a wireless transceiver circuit may be compatible with the Wireless Local Area Network IEEE 802.11 standard known as WiFi. A transceiver circuit may be configured to detect a WiFi access point in proximity to the analyte meter 10 and to transmit and receive data from such a detected WiFi access point. A wireless transceiver circuit may be compatible with the Bluetooth protocol and is configured to detect and process data transmitted from a Bluetooth hub in proximity to the analyte meter 10. A wireless transceiver circuit may be compatible with the near field communication (“NFC”) standard and is configured to establish radio communication with, for example, an NFC compliant reader device capable of gathering analyte test measurements in proximity to the analyte meter 10. A wireless transceiver circuit may comprise a circuit for cellular communication with cellular networks and is configured to detect and link to available cellular communication towers.
A power supply module 56 is electrically connected to all modules in the housing 11 and the processing unit 50 to supply electric power thereto. The power supply module 56 may comprise standard or rechargeable batteries, or an AC power supply that may be activated when the analyte meter 10 is connected to a source of AC power. The power supply module 56 is also electrically connected to the processing unit 50 over the communication interface 55 such that processing unit 50 can monitor a power level remaining in a battery of the power supply module 56.
In addition to connecting external storage for use by the analyte meter 10, the data port 13 can be used to accept a suitable connector attached to a connecting lead, thereby allowing the analyte meter 10 to be wired to an external device such as a personal computer. Data port 13 can be any port that allows for transmission of data, power, or a combination thereof, such as a serial, USB, or a parallel port.
With reference to
The camera 66 transmits an image of the test strip 24 to the display module 58 which generates image data to be displayed on the display 14 for more comfortable viewing of the test strip 24 by a user, as shown in
With reference to
With respect to
At step 303, the image of the test strip 24 captured by the camera is transmitted to the display 14, which transmission may occur simultaneously with step 302 so that the user may adjust the position of the display panel 30. After positioning the display panel 30 together with the camera 66, the user then may observe the test strip 24 in the display 14 while simultaneously applying a sample to an inlet of the test strip sample chamber 34, at step 304.
The image displayed may be improved over a direct view of the test strip 24 in several ways. One improvement comprises enlarging, or magnifying, the image so that the test strip 24 appears in the display 14 in a larger than actual size for ease of viewing by the user and for more accurate placement of the sample in the sample chamber 34. Another example of improvement of the image may comprise electronically and automatically brightening the image of the test strip 24 if the user is checking blood glucose concentration in a darkened or semi-lighted area, by including an ambient light detector in the test meter 10. As another example, well known image enhancement circuits may be included in the test meter 10 to improve sharpness, edge detection, and overall image brightness and resolution. The light source 52 may be automatically controlled by the microcontroller 50 for brightness by receiving signals from an ambient light detector (not shown). In one embodiment, the light source 52 may comprise an infra red LED for illuminating the test strip 24 in a dark area, such as in a movie theater, without generating light visible to the human eye but which light may be detected by the camera 66. The illumination drive 54 may comprise, for example, a digital-to-analog converter output providing a variable DC voltage between zero (0) and 2V or a pulse-width-modulated (PWM) voltage signal with duty cycle varying between 0 and 100%. The LED may be driven by a DC current varying between zero (0) and the maximum for the LED(s), which may be about 30 mA, or it may be driven by a PWM current signal with varying duty cycle between 0 and 100%.
The camera output signal may be compatible with an 8 to 14-bit parallel camera interface transmitting at a rate of up to about 54 MB/s. Autofocus camera models connectable to a 24-pin slot may be obtained from Sanm Technology Co., Ltd., of Shenzhen, China, which include 300K, 1.3M and 2.0M pixel color digital video CMOS camera modules, convertible to infrared light capture mode, providing magnification options ranging from about 1.5× to about 5×.
As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method, or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.), or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “circuitry,” “module,” and/or “system.” Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having computer readable program code embodied thereon.
Any combination of one or more computer readable medium(s) may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible, non-transitory medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.
Program code and/or executable instructions embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.
The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
Furthermore, the various methods described herein can be used to generate software codes using off-the-shelf software development tools. The methods, however, may be transformed into other software languages depending on the requirements and the availability of new software languages for coding the methods.
While the invention has been described in terms of particular variations and illustrative figures, those of ordinary skill in the art will recognize that the invention is not limited to the variations or figures described. In addition, where methods and steps described above indicate certain events occurring in certain order, those of ordinary skill in the art will recognize that the ordering of certain steps may be modified and that such modifications are in accordance with the variations of the invention. Additionally, certain of the steps may be performed concurrently in a parallel process when possible, as well as performed sequentially as described above. Therefore, to the extent there are variations of the invention, which are within the spirit of the disclosure or equivalent to the inventions found in the claims, it is the intent that this patent will cover those variations as well.
