APPLICATION FOR
`UNITED STATES PATENT
`IN THE NAME OF
`
`JOHN J. MASTROTOTARO, EDWARD CHERNOFF, DAVID CHOY,
`JAMES HENKE, RICHARD PURVIS, AND PETER HONG
`
`ASSIGNED TO
`
`MEDTRONIC MINIMED, INC.
`
`FOR
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`TELEMETERED CHARACTERISTIC MONITOR SYSTEM
`AND METHOD OF USING THE SAME
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`DOCKET NO. PD00291 CIP
`
`Richard Yoon, Reg. No.: 42,247
`Medtronic MiniMed, Inc.
`18000 Devonshire Street
`Northridge, California 91326
`(818) 576-4110
`(818) 576-6202 facsimile
`
`Express Mail No. EV 119 698 309 US
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`PATENT
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`TITLE
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`Telemetered Characteristic Monitor System And Method Of Using The Same
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`RELATED APPLICATIONS
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`5
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`This application is a continuation-in-part of U.S. Patent Application Serial No.
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`10/898,589, filed on July 23, 2004, which is a continuation of U.S. Patent Application Serial No.
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`10/465,715, filed on December 17, 1999 and issued as U.S. Patent No. 6,809,653 on October 26,
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`2005, which is a continuation of U.S. Patent Application Serial No. 09/377,472, filed on August
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`19, 1999 and later abandoned, which claimed priority from U.S. Provisional Application Serial
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`10 No. 60/103,812, filed on Oc,tober 8, 1998, each of which are herein incorporated by reference.
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`FIELD OF THE INVENTION
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`This invention relates to telemetered subcutaneous sensor devices and, in particular
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`embodiments, to devices and methods for wireless communication between an implantable
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`subcutaneous sensor set at a selected insertion site within the body of a user and a remotely
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`located characteristic monitor.
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`BACKGROUND OF THE INVENTION
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`Over the years, a variety of implantable electrochemical sensors have been developed for
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`detecting and/or quantifying specific agents or compositions in a patient's blood. For instance,
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`glucose sensors have been developed for use in obtaining an indication of blood glucose levels in
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`a diabetic patient. Such readings are useful in monitoring and/or adjusting a treatment regimen
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`which typically includes the regular administration of insulin to the patient. Thus, blood glucose
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`readings improve medical therapies with semi-automated medication infusion pumps of the
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`25
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`external type, as generally described in U.S. Patent Nos. 4,562,751; 4,678,408; and 4,685,903; or
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`automated implantable medication infusion pumps, as generally described in U.S. Patent No.
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`4,573,994, which are herein incorporated by reference.
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`Generally, small and flexible electrochemical sensors can be used to obtain periodic
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`readings over an extended period of time. In one form, flexible subcutaneous sensors are
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`constructed in accordance with thin film mask techniques in which an elongated sensor includes
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`5
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`thin film conductive elements encased between flexible insulative layers of polyimide sheets or
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`similar material. Such thin film sensors typically include a plurality of exposed electrodes at one
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`end for subcutaneous placement with a user's interstitial fluid, blood, or the like, and a
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`corresponding exposed plurality of conductive contacts at another end for convenient external
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`electrical connection with a suitable monitoring device through a wire or cable. Typical thin film
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`10
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`sensors are described in commonly assigned U.S. Patent Nos. 5,390,671; 5,391,250; 5,482,473;
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`and 5,586,553 which are incorporated by reference herein. See also U.S. Patent No. 5,299,571.
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`Drawbacks to the use of implantable sensors arise from the use of a wired connection
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`between the implantable sensor set and the monitor. The use of the wire or cable is an additional
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`inconvenience to users that already utilize an external infusion pump that includes an infusion
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`insertion set and tube to infuse the medication. Also, the preferred site for some sensing device
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`may be. inconvenient for connection by wire to a characteristic monitor. For implantable pumps,
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`the wire or cable negates the very benefit of having an internal device without external wires or
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`cables. For Type 2 diabetics, who do not necessarily need or use an infusion pump, the use of a
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`cable is seen as an inconvenience that may inhibit use of the device. In addition, the use of a
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`20 wire or cable limits a user's ability to position the monitor, since it can be placed no further away
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`than the ultimate length of the wire or cable. Thus, the user must normally wear the monitor,
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`which can be problematic. For example, removal of the monitor for sleeping can be difficult,
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`since a user would tend to become "tangled" in the wire or cable, between the sensor and the
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`monitor, during the normal tossing and turning that occurs during sleep. Furthermore, the more
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`connections the user must deal with (e.g., infusion pump and catheter and/or monitor with wire to
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`sensor), the more complicated it is to use the devices, and the less likely the user will maintain
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`compliance with the ~edical regimen due to perceived and actual difficulties with all of the wires
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`and cables.
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`SUMMARY OF THE DISCLOSURE
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`It is an object of an embodiment of the present invention to provide an improved
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`telemetered implantable sensor set (such as a subcutaneous or percutaneous sensor) and monitor
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`connection device, which obviates for practical purposes, the above mentioned limitations.
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`According to an embodiment of the invention, a telemetered characteristic monitor
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`system includes a remotely located data receiving device, a sensor for producing signal indicative
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`10
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`of a characteristic of a user, and a transmitter device. In preferred embodiments, the transmitter
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`device includes a housing, a sensor connector, a processor, and a transmitter. A potentiostat
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`within the transmitter device may be coupled to the sensor connector and applies power to the
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`sensor. The sensor connector receives the produced signals from the sensor. The processor is
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`coupled to the sensor connector and processes the signals from the sensor for delivery to the
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`remotely located data receiving device. The transmitter is coupled to the processor for wirelessly
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`transmitting the processed signals to the remotely located data receiving device. In preferred
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`embodiments, the data receiving device is a characteristic monitor. However, in other
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`embodiments, the data receiving device is a data receiver that provides data to another device, an
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`RF programmer, a medication delivery device (such as an infusion pump), or the like.
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`In particular embodiments, the transmitter of the transmitter device transmits the
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`processed signals by radio frequencies. In other embodiments, the sensor may be implanted in
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`and/or through subcutaneous, dermal, sub-dermal, intra-peritoneal or peritoneal tissue, and the
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`sensor connector of the transmitter device includes a cable that is connected to the sensor. Also,
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`the implantable sensor can be configured for a wired connection to a characteristic monitor, and
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`the sensor connector of the transmitter device is formed to connect to the configured implantable
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`sensor. Still further embodiments of the transmitter device include a receiver to receive data and
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`instructions from the characteristic monitor, or the like.
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`Embodiments of the transmitter device (when used with a subcutaneous or percutaneous
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`sensor) may include a bio-compatible adhesive to secure the housing to a skin surface of the user.
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`Preferably, the housing of the transmitter device is less than about 3.0 inches in diameter by 0.5
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`5
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`inches thick. In addition, the housing is resistant to fluids when immersed in a fluid, operable in
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`a temperature range of 0°C to 50°C, and has an operable life of at least 3 months. If the sensor is
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`fully implanted, the transmitter that is connected to the sensor may be secured by sutures, sewing
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`rings, or the like.
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`Other features and advantages of the invention will become apparent from the following
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`detailed description, taken in conjunction with the accompanying drawings which illustrate, by
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`way of example, various features of embodiments of the invention.
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`A detailed description of embodiments of the invention will be made with reference to the
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`accompanying drawings, wherein like numerals designate corresponding parts in the several
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`figures.
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`Fig. 1 is a is a perspective view illustrating a subcutaneous sensor insertion set and
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`telemetered characteristic monitor transmitter device embodying the novel features of the
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`invention;
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`Fig. 2 is an enlarged longitudinal vertical section taken generally on the line 2-2 of Fig. 1;
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`Fig. 3 is an enlarged longitudinal sectional of a slotted insertion needle used in the
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`insertion set of Figs. 1 and 2;
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`Fig. 4 is an enlarged transverse section taken generally on the line 4-4 of Fig. 3;
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`Fig. 5 is an enlarged transverse section taken generally on the line 5-5 of Fig. 3;
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`Fig. 6 is an enlarged fragmented sectional view corresponding generally with the
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`encircled region 6 of Fig. 2; and
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`Fig. 7 is an enlarged transverse section taken generally on the line 7-7 of Fig. 2.
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`Fig. 8(a) is a top plan and partial cut-away view of the telemetered characteristic monitor
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`transmitter device in accordance with the embodiment shown in Fig. 1.
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`Fig. 8(b) is a simplified block diagram of the printed circuit board of the telemetered
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`characteristic monitor transmitter device in accordance with the embodiments shown in Fig. 1.
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`Fig. 9 is a timing diagram illustrating an embodiment of a message and timing format
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`used by the telemetered characteristic monitor transmitter device shown in Fig. 1.
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`Fig. 10 is a simplified block diagram of a characteristic monitor used in accordance with
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`an embodiment of the present invention.
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`Fig. 11 is a timing diagram for the characteristic monitor shown in Fig. 10.
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`Fig. 12 is another timing diagram for the characteristic monitor shown in Fig. 10.
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`Fig. 13 is a simplified block diagram of a telemetered characteristic monitor transmitter
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`and sensor set system in accordance with another embodiment of the present invention.
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`Fig. 14 is a simplified block diagram of a telemetered characteristic monitor transmitter
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`and characteristic monitor system in accordance with still another embodiment of the present
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`invention.
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`Fig. 15 is a perspective view illustrating another preferred embodiment of the
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`subcutaneous sensor insertion set and telemetered characteristic monitor transmitter device when
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`mated together in relation to the characteristic monitor system.
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`Fig. 16 is a top view of the subcutaneous sensor insertion set and telemetered
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`characteristic monitor transmitter device when separated.
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`Figs. 17 and 18 are two perspective views of the characteristic monitor transmitter in
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`accordance with the embodiment shown in Fig. 16.
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`Figs. 19 and 20 are top and bottom plan and partial cut-away views of the telemetered
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`characteristic monitor transmitter device in accordance with the embodiment shown in Fig. 16.
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`Fig. 21 is a side view of the charger associated with telemetered characteristic monitor
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`transmitter device.
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`Fig. 22 is a perspective view of the charger associated with telemetered characteristic
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`monitor transmitter device.
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`Fig. 23 is a perspective view of the charger mated with telemetered characteristic monitor
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`transmitter device.
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`Figs. 24 and 25 are simplified block diagrams of the charger system used to charge the
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`telemetered characteristic monitor transmitter device.
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`DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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`As shown in the drawings for purposes of illustration, the invention is embodied in a
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`telemetered characteristic monitor transmitter coupled to a sensor set, that may be implanted in
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`and/or through subcutaneous, dermal, sub-dermal, inter-peritoneal or peritoneal tissue, that
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`transmits data from the sensor set to the characteristic monitor for determining body
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`characteristics. In preferred embodiments of the present invention, the sensor set and monitor are
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`for determining glucose levels in the blood and/or body fluids of the user without the use of, or
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`necessity of, a wire or cable connection between the transmitter and the monitor. However, it
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`will be recognized that further embodiments of the invention may be used to determine the levels
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`of other agents, characteristics or compositions, such as hormones, cholesterol, medication
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`concentrations, pH, oxygen saturation, viral loads ( e.g., HIV), or the like. In other embodiments,
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`the sensor set may also include the capability to be programmed or calibrated using data received
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`by the telemetered characteristic monitor transmitter device, or may be calibrated at the monitor
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`device (or receiver). The telemetered characteristic monitor system is primarily adapted for use
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`in subcutaneous human tissue. However, still further embodiments may be placed in other types
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`of tissue, such as muscle, lymph, organ tissue, veins, arteries or the like, and used in animal
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`tissue. Embodiments may provide sensor readings on an intermittent or continuous basis.
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`The telemetered characteristic monitor system 1, in accordance with a preferred
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`embodiment of the present invention include a percutaneous sensor set 10, a telemetered
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`characteristic monitor transmitter device 100 and a characteristic monitor 200. The percutaneous
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`sensor set 10 utilizes an electrode-type sensor, as described in more detail below. However, in
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`alternative embodiments, the system may use other types of sensors, such as chemical based,
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`optical based or the like. In further alternative embodiments, the sensors may be of a type that is
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`used on the external surface of the skin or placed below the skin layer of the user. Preferred
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`embodiments of a surface mounted sensor would utilize interstitial fluid harvested from
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`underneath the skin. The telemetered characteristic monitor transmitter 100 generally includes
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`the capability to transmit data. However, in alternative embodiments, the telemetered
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`10
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`characteristic monitor transmitter 100 may include a receiver, or the like, to facilitate two-way
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`communication between the sensor set 10 and the characteristic monitor 200. The characteristic
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`monitor 200 utilizes the transmitted data to determine the characteristic reading. However, in
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`alternative embodiments, the characteristic monitor 200 may be replaced with a data receiver,
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`storage and/or transmitting device for later processing of the transmitted data or programming of
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`the telemetered characteristic monitor transmitter 100.
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`In addition, a relay or repeater 4 may be used with a telemetered characteristic monitor
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`transmitter 100 and a characteristic monitor 200 to increase the distance that the telemetered
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`characteristic monitor transmitter 100 can be used with the characteristic monitor 200, as shown
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`in Fig. 13. For example, the relay 4 could be used to provide information to parents of children
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`using the telemetered characteristic monitor transmitter 100 and the sensor set 10 from a
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`distance. The information could be used when children are in another room during sleep or
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`doing activities in a location remote from the parents. In further embodiments, the relay 4 can
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`include the capability to sound an alarm. In addition, the relay 4 may be capable of providing
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`telemetered characteristic monitor transmitter 100 data from the sensor set 10, as well as other
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`data, to a remotely located individual via a modem connected to the relay 4 for display on a
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`monitor, pager or the like. The data may also be downloaded through a Communication-Station
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`8 to a remotely located computer 6 such as a PC, lap top, or the like, over communication lines,
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`by modem or wireless connection, as shown in Fig. 14. Also, some embodiments may omit the
`Comm~ication Station 8 and uses a direct modem or wireless connection to the computer 6. In
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`further embodiments, the telemetered characteristic monitor transmitter 100 transmits to an RF
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`programmer, which acts as a relay, or shuttle, for data transmission between the sensor set 10 and
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`a PC, laptop, Communication-station, a data processor, or the like. In further alternatives, the
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`telemetered characteristic monitor transmitter 100 may transmit an alarm to a remotely located
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`device, such as a communication-station, modem or the like to summon help. In addition, further
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`embodiments may include the capability for simultaneous monitoring of multiple sensors and/or
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`10
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`include a sensor for multiple measurements.
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`Still further embodiments of the telemetered characteristic monitor transmitter 100 may
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`have and use an input port for direct (e.g., wired) connection to a programming or data readout
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`device and/or be used for calibration of the sensor set 10. Preferably, any port would be water
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`proof ( or water resistant) or include a water proof, or water resistant, removable cover.
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`The purpose of the telemetered characteristic monitor system 1 (see Fig. 2) is to provide
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`for better treatment and control in an outpatient or a home use environment. For example, the
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`monitor system 1 can provide indications of glucose levels, a hypoglycemia/hyperglycemia alert
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`and outpatient diagnostics. It is also useful as an evaluation tool under a physician's supervision.
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`The monitor system 1 also removes inconvenience by separating the monitor electronics
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`20
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`into two separate devices; a telemetered characteristic monitor transmitter 100, which attaches to
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`the implantable sensor set 10; and a characteristic monitor 200 (or other receiver), which is
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`carried like a pager. This provides several advantages over wire connected devices. For
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`instance, the user can more easily conceal the presence of the monitor system 1, since a wire will
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`not be visible (or cumbersome), within clothing. Such remote communication also provides
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`greater convenience and flexibility in the placement of the sensor. It also makes it is easier to
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`protect the characteristic monitor 200, which can be removed from the user's body during
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`showers, exercise, sleep or the like. In addition, the use of multiple components ( e.g., transmitter
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`100 and characteristic monitor 200) facilitates upgrades or replacements, since one module or the
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`other can be modified or replaced without requiring complete replacement of the monitor system
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`1. Further, the use of multiple components can improve the economics of manufacturing, since
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`5
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`some components may require replacement on a more frequent basis, sizing requirements may be
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`different for each module, there may be different assembly environment requirements, and
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`modifications can be made without affecting the other components.
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`The telemetered characteristic monitor transmitter 100 takes characteristic information,
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`such as glucose data or the like, from the percutaneous sensor set 10 and transmits it via wireless
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`10
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`telemetry to the characteristic monitor 200, which displays and logs the received glucose
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`readings. Logged data can be downloaded from the characteristic monitor 200 to a personal
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`computer, laptop, or the like, for detailed data analysis. In further embodiments, the telemetered
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`characteristic monitor system 1 may be used in a hospital environment or the like. Still further
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`embodiments of the present invention may include one or more buttons (on the telemetered
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`characteristic monitor transmitter 100 or characteristic monitor 200) to record data and events for
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`later analysis, correlation, or the like. In addition, the telemetered characteristic monitor
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`transmitter 100 may include a transmit on/off button for compliance with safety standards and
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`regulations to temporarily suspend transmissions. Further buttons can include a sensor on/off
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`button to conserve power and to assist in initializing the sensor set I 0. The telemetered
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`characteristic monitor transmitter 100 and characteristic monitor 200 may also be combined with
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`other medical devices to combine other patient data through a common data network and
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`telemetry system.
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`Further embodiments of the percutaneous sensor set IO would monitor the temperature of
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`the sensor set 10, which can then be used to improve the calibration of the sensor. For instance,
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`for a glucose sensor, the enzyme reaction activity may have a known temperature coefficient.
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`The relationship between temperature and enzyme activity can be used to adjust the sensor values
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`to more accurately reflect the actual characteristic levels. In addition to temperature
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`measurements, the oxygen saturation level can be determined by measuring signals from the
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`various electrodes of the sensor set 10. Once obtained, the oxygen saturation level may be used
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`in calibration of the sensor set 10 due to changes in the oxygen saturation levels, and its effects
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`5
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`on the chemical reactions in the sensor set 10. For instance, as the oxygen level goes lower the
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`sensor sensitivity may be lowered. The oxygen level can be utilized in calibration of the sensor
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`set 10 by adjusting for the changing oxygen saturation. In alternative embodiments, temperature
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`measurements may be used in conjunction with other readings to determine the required sensor
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`calibration.
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`10
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`As shown in Figs. 1-7, a percutaneous sensor set 10 is provided for subcutaneous
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`placement of an active portion of a flexible sensor 12 (see Fig. 2), or the like, at a selected site in
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`the body of a user. The subcutaneous or percutaneous portion of the sensor set 10 includes a
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`hollow, slotted insertion needle 14, and a cannula 16. The needle 14 is used to facilitate quick
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`and easy subcutaneous placement of the cannula 16 at the subcutaneous insertion site. Inside the
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`cannula 16 is a sensing portion 18 of the sensor 12 to expose one or more sensor electrodes 20 to
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`the user's bodily fluids through a window 22 formed in the cannula 16. After insertion, the
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`insertion needle 14 is withdrawn to leave the cannula 16 with the sensing portion 18 and the
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`sensor electrodes 20 in place at the selected insertion site.
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`In preferred embodiments, the percutaneous sensor set IO facilitates accurate placement
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`20
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`of a flexible thin film electrochemical sensor 12 of the type used for monitoring specific blood
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`parameters representative of a user's condition. Preferably, the sensor 12 monitors glucose levels
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`in the body, and may be used in conjunction with automated or semi-automated medication
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`infusion pumps of the external or implantable type as described in U.S. Pat. Nos. 4,562,751;
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`4,678,408; 4,685,903 or 4,573,994, to control delivery of insulin to a diabetic patient.
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`25
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`Preferred embodiments of the flexible electrochemical sensor 12 are constructed in
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`accordance with thin film mask techniques to include elongated thin film conductors embedded
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`or encased between layers of a selected insulative material such as polyimide film or sheet, and
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`membranes. The sensor electrodes 20 at a tip end of the sensing portion 18 are exposed through
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`one of the insulative layers for direct contact with patient blood or other body fluids, when the
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`sensing portion 18 (or active portion) of the sensor 12 is subcutaneously placed at an insertion
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`5
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`site. The sensing portion 18 is joined to a connection portion 24 (see Fig. 2) that terminates in
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`conductive contact pads, or the like, which are also exposed through one of the insulative layers.
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`In alternative embodiments, other types of implantable sensors, such as chemical based, optical
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`based, or the like, may be used.
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`As is known in the art, and illustrated schematically in Fig. 2, the connection portion 24
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`10
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`and the contact pads are generally adapted for a direct wired electrical connection to a suitable
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`monitor 200 for monitoring a user's condition in response to signals derived from the sensor
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`electrodes 20. Further description of flexible thin film sensors of this general type are be found
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`in U.S. Patent. No. 5,391,250, entitled METHOD OF FABRICATING THIN FILM SENSORS,
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`which is herein incorporated by reference. The connection portion 24 may be conveniently
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`15
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`connected electrically to the monitor 200 or a telemetered characteristic monitor transmitter 100
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`by a connector block 28 (or the like) as shown and described in U.S. Pat. No. 5,482,473, entitled
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`FLEX CIRCUIT CONNECTOR, which is also herein incorporated by reference. Thus, in
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`accordance with embodiments of the present invention, subcutaneous sensor sets 10 are
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`configured or formed to work with either a wired or a wireless characteristic monitor system.
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`20
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`The proximal part of the sensor 12 is mounted in a mounting base 30 adapted for
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`placement onto the skin of a user. As shown, the mounting base 30 is a pad having an underside
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`surface coated with a suitable pressure sensitive adhesive layer 32, with a peel-off paper strip 34
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`normally provided to cover and protect the adhesive layer 32, until the sensor set 10 is ready for
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`use. As shown in Figs. 1 and 2, the mounting base 30 includes upper and lower layers 36 and 38,
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`25 with the connection portion 24 of the flexible sensor 12 being sandwiched between the layers 36
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`and 38. The connection portion 24 has a forward section joined to the active sensing portion 18
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`of the sensor 12, which is folded angularly to extend downwardly through a bore 40 formed in
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`the lower base layer 38. In preferred embodiments, the adhesive layer 32 includes an anti(cid:173)
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`bacterial agent to reduce the chance of infection; however, alternative embodiments may omit the
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`agent. In the illustrated embodiment, the mounting base is generally rectangular, but alternative
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`5
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`embodiments may be other shapes, such as circular, oval, hour-glass, butterfly, irregular, or the
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`like.
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`The insertion needle 14 is adapted for slide-fit reception through a needle port 42 formed
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`in the upper base layer 36 and further through the lower bore 40 in the lower base layer 38. As
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`shown, the insertion needle 14 has a sharpened tip 44 and an open slot 46 which extends
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`10
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`longitudinally from the tip 44 at the underside of the needle 14 to a position at least within the
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`bore 40 in the lower base layer 36. Above the mounting base 30, the insertion needle 14 may
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`have a full round cross-sectional shape, and may be closed off at a rear end of the needle 14.
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`Further description of the needle 14 and the sensor set 10 are found in U.S. Patent No. 5,586,553,
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`entitled "TRANSCUTANEOUS SENSOR INSERTION SET" and co-pending U.S. Patent
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`15
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`Application Serial No. 08/871,831, entitled 'DISPOSABLE SENSOR INSERTION
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`ASSEMBLY," which are herein incorporated by reference.
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`The cannula 16 is best shown in Figs. 6 and 7, and includes a first portion 48 having
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`partly-circular cross-section to fit within the insertion needle 14 that extends downwardly from
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`the mounting base 30. In alternative embodiments, the first portion 48 may be formed with a
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`solid core; rather than a hollow core. In preferred embodiments, the cannula 16 is constructed
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`from a suitable medical grade plastic or elastomer, such as polytetrafluoroethylene, silicone, or
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`the like. The cannula 16 also defines an open lumen 50 in a second portion 52 for receiving,
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`protecting and guideably supporting the sensing portion 18 of the sensor 12. The cannula 16 has
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`one end fitted into the bore 40 formed in the lower layer 38 of the mounting base 30, and the
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`cannula 16 is secured to the mounting base 30 by a suitable adhesive, ultrasonic welding, snap fit
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`or other selected attachment method. From the mounting base 30, the cannula 16 extends
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`PATENT
`PD00291 CIP
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`angularly downwardly with the first portion 48 nested within the insertion needle 14, and
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`terminates before the needle tip 44. At least one window 22 is formed in the lumen 50 near the
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`implanted end 54, in general alignment with the sensor electrodes 20, to permit direct electrode
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`exposure to the user's bodily fluid when the sensor 12 is subcutaneously placed. Alternatively, a
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`5 membrane can cover this area with a porosity that controls rapid diffusion of glucose through the
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`membrane.
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`As shown in Figs. 1, 2 and 8(a), the telemetered characteristic monitor transmitter 100 is
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`coupled to a sensor set 10 by a cable 102 through a connector 104 that is electrically coupled to
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`the connector block 28 of the connector portion 24 of the sensor set 10. In alternative
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`10
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`embodiments, the cable 102 may be omitted, and the telemetered characteristic monitor
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`transmitter 100 may include an appropriate connector (not shown) for direct connection to the
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`connector portion 24 of the sensor set 10 or the sensor set 10 may be modified to have the
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`connector portion 24 positioned at a different location, such as for example, on the top of the
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`sensor set 10 to facilitate placement of the telemetered characteristic monitor transmitter over the
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`15
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`subcutaneous sensor set 10. This would minimize the amount of skin surface covered or
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`contacted by medical devices, and tend to minimize movement of the sensor set 10 relative to the
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`telemetered characteristic monitor transmitter 100. Specifically, according to another preferred
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`embodiment of the present invention, characteristic monitor transmitter 100 and the sensor set 10
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`have been modified to allow a side-by side direct connection between the characteristic monitor
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`20
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`transmitter 100' and the sensor set 10' such that the characteristic monitor transmitter 100'
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`detachable from the sensor set 10', as seen in Fig. 15. As shown in Figs. 16-18, according to the
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`preferred embodiments of the present invention, the characteristic monitor transmitter 100' is
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`coupled to a sensor set 1 O' using a male/female connection scheme for direct connection to the
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`the sensor set 1 O'. In preferred embodiments, the characteristic monitor transmitter 100' shall
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`25
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`have a female connector interface 400 built into the housing 1100 of the characteristic monitor
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`transmitter 100'. Detents at the female connector interface 400 are used to mate and lock with
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`-14-
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`Page 14 of 50
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`PATENT
`PD00291 CIP
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`locking prongs located on the male sensor connector 600 of the sensor set 1 0'. Alternatively,
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`other detachable connector systems may be used including the modification of the connection
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`scheme to place a female connector on the sensor 1 O' and the male connector on characteristic
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`monitor transmitter 100'. This provides several advantages over other embodiments of the
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`5
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`present invention. First of all, the use of multiple components in the monitor system 1' ( e.g.,
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`sensor set 1 O', transmitter 100' and characteristic monitor 200) facilitates upgrades or
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`replacements, since one module or the other can be modified or replaced without requiring
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`complete replacement of the monitor system 1 '. In other embodiments, the transmitter 100 was
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`discarded along with the sensor set 10 after the 3 to 5 day use period since they were directly
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`10
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`connected. Another key improvement of the characteristic transmitter 100' of the present
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`invention compared to other embodiments is the relative size of the transmitter I 00'. The size
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`of the transmitter 100' has been reduced to fit directly onto the sensor set 1 O' and be supported
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`by the sensor set 10' itself. Unlike the other embodiments of the present invention that required
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`the transmitter 100 to be attached separately to the body of a user by a separate adhesive tape
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`15
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`118, the transmitter 100' can remain fixed in its location by being attached to the sensor set 10'.
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`In other words, a single adhesive tape 34 used to attach the sensor set to the patient can also
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`support the transmitter 100'. In further alternative embodiments, the cable 102 and the
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`connector 104 may be formed as add-on adapters to fit different types of connectors on different
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`types or kinds of sensor sets. The use of adapters would facilitate adaptation of the telemetered
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`20
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`characteristic monitor transmitter I 00 to work with a wide variety of