Abstract: A sensor (e.g., an optical sensor) that may be implanted within a living animal (e.g., a human) and may be used to measure an analyte (e.g., glucose or oxygen) in a medium (e.g., interstitial fluid, blood, or intraperitoneal fluid) within the animal. The sensor may include a sensor housing, an analyte indicator covering at least a portion of the sensor housing, and one or more therapeutic agents. The one or more therapeutic agents may reduce deterioration of the analyte indicator. The one or more therapeutic agents may be incorporated within the analyte indicator, a membrane covering at least a portion of the analyte indicator, and/or one or more drug eluting polymer matrices, which may be external to or within the sensor housing.

Abstract: An inductive sensor system for remote powering and communication with an analyte sensor (e.g., a fully implantable analyte sensor). The system may include an analyte sensor and transceiver. The system may be ferrite-enhanced. The transceiver may implement a passive telemetry for communicating with the analyte sensor via an inductive magnetic link for both power and data transfer. The link may be a co-planar, near field communication telemetry link. The transceiver may include a reflection plate configured to focus flux lines linking the transceiver and the sensor uniformly beneath the transceiver. The transceiver may include an amplifier configured to amplify battery power and provide radio frequency (RF) power to a transceiver antenna.

Abstract: A system and method for detecting the amount or concentration of an analyte in a medium in living organism. The system may include an analyte sensor module and a transmitter module, which may be separate and distinct components. The analyte sensor module and transmitter module may be at different locations but connected by one or more transmission elements. The analyte sensor may include indicator elements configured to exhibit a detectable property based on the amount or concentration of the analyte in proximity to the indicator elements. The analyte sensor may include sensor elements configured to generate a data signal based on the detectable property exhibited by the indicator elements. The transmission elements may be configured to convey data signals generated by the sensor elements from the analyte sensor module to the transmitter module. The transmitter module may include an antenna.

Abstract: A transceiver for interfacing with an analyte sensor. The transceiver may include an interface device and a notification device. The interface device may be configured to convey a power signal to the analyte sensor and to receive data signals from the analyte sensor. The notification device may be configured to generate one or more of a vibrational, aural, and visual signal based on one or more data signals received from the analyte sensor. The interface device of the transceiver may receive analyte data from the analyte sensor, and the transceiver may comprise a processor configured to calculate an analyte concentration value based on the received analyte data. The notification device may be configured to generate one or more of aural, visual, or vibrational alarm when the calculated analyte concentration value exceeds or falls below a threshold value.

Abstract: A sensor (e.g., an optical sensor) that may be placed within a living animal (e.g., a human) and may be used to measure an analyte (e.g., glucose or oxygen) in a medium (e.g., interstitial fluid) within the animal. The sensor may include a sensor housing and a polymer graft including indicator molecules and covering at least a portion of the sensor housing. The opacity of the polymer graft may remain substantially the same (i.e., may have little or no variation) over time. The sensor may include a photodetector, and variation in the opacity of the polymer graft does not cause a significant change in a measurement signal output by the photodetector. The polymer hydrogel may be made of polymers including acrylic acid and/or polyethylene glycol.

Abstract: Tunneling and implantation tools that may be used to implant a sensor within a living animal. For example, the sensor may be implanted in subcutaneous tissue below the skin. The sensor may be disk-shaped and may be capable of being compressed (e.g., wrapped) in a more cylindrical shape. The sensor may or may not be able expand on its own (i.e., to force tissue apart to accommodate the sensor in its full disk-shape) after insertion into the living animal. The tunneling tool may have a flat and wide tip, a vibration device, arms attached to a rod at its tip, a spring in a hollow tube at the end of a rod, and/or oscillating teeth. The implantation tool may have jaws that clamp and then release the sensor and/or rods that insert into channels of the sensor and spread apart to assist in opening up a compressed sensor.

Abstract: A sensor system including an implantable sensor and an external transceiver. Aspects of the sensor system may provide improved implantation and antenna orientation of the implanted sensor. The sensor may include a sensor antenna, the transceiver may include a transceiver antenna. In some embodiments, the sensor antenna and/or transceiver antenna may include a first set of coils oriented in a first plane and a second set of coils oriented in a second plane that is different than the first plane. In some embodiments, the sensor may have a geometry that will prevent or reduce movement and/or rotation of the implanted sensor. For instance, in some embodiments, the sensor may be enclosed in silicon that contains antenna coils and/or include wings, a fluid filled sack, a swelling material, an expansion material, and/or arms.

Abstract: The burr hole plug comprises a plug base configured for being mounted around a burr hole, and having an aperture through which an elongated medical device exiting the burr hole may pass. The burr hole plug further comprises a retainer configured for being mounted within the plug base aperture. The retainer includes a retainer support, a slot formed in the retainer support for receiving the medical device, and a clamping mechanism having a clamping bar and a flange slidably engaged with the retainer support to laterally slide the clamping bar to secure the medical device. A method comprises introducing the medical device through the burr hole, mounting the plug base around the burr hole, mounting the retainer within the plug base aperture, receiving the medical device into the slot, and sliding the slidable flange relative to the retainer support to laterally slide to secure the medical device.

Abstract: A sensor that may be used to detect the presence, amount, and/or concentration of an analyte in a medium within an animal. The sensor may include a sensor housing, an indicator element embedded within and/or covering at least a portion of the sensor housing, and a membrane over the indicator element. The membrane may reduce indicator element deterioration by preventing immune cells, such as white blood cells, from contacting the indicator element, substantially prevent transmission of light of at least a specified wavelength or range of wavelengths through the membrane, and/or permit the analyte to pass through to the indicator element. The membrane may be an opaque diffusion membrane. The sensor may include a foil. The foil may block light and/or reduce indicator element deterioration. The membrane may reduce oxidation of the indicator element.

Abstract: A sensor that may be used to detect the presence, amount, and/or concentration of an analyte in a medium within an animal. The sensor may include a sensor housing, an indicator element embedded within and/or covering at least a portion of the sensor housing, and a membrane over the indicator element. The membrane may reduce indicator element deterioration by preventing immune cells, such as white blood cells, from contacting the indicator element, substantially prevent transmission of light of at least a specified wavelength or range of wavelengths through the membrane, and/or permit the analyte to pass through to the indicator element. The membrane may be an opaque diffusion membrane. The sensor may include a foil. The foil may block light and/or reduce indicator element deterioration. The membrane may reduce oxidation of the indicator element.

Abstract: A burr hole plug comprises a plug base configured for being mounted around a burr hole. The plug base includes an aperture through which an elongated medical device exiting the burr hole may pass. The burr hole plug further comprises a retainer configured for being mounted within the aperture of the plug base. The retainer further includes first and second slidable clamping mechanisms configured for securing the medical devices therebetween within the aperture of the plug base. A method comprises introducing the medical device through the burr hole, mounting a plug base around the burr hole, such that the medical device extends through the plug base aperture, mounting the retainer within the aperture of the plug base, and sliding the first and second clamping mechanisms secure the medical device therebetween.

Abstract: Improved external chargers for charging an implantable medical device, and particularly useful in charging a plurality of such devices, are disclosed. Each of the various embodiments include design elements for mechanically manipulating the position of one or more charging coils within the external charger to customize the magnetic charging field as appropriate for the charger/implantable device environment. For example, a single charging coil may be moved within a housing of the external charger to direct the charging field of the coil towards the currently “coldest” implant, i.e., the implant with the lowest coupling to the external charger. The one or more charging coils may be mechanically manipulated within the external charger housing in a number of ways, including by using linear actuators, by inflatable bladders, or even by hand.

Abstract: Improved external chargers for charging an implantable medical device, and particularly useful in charging a plurality of such devices, are disclosed. Each of the various embodiments include a plurality of field customization coils for customizing the magnetic charging field generated by the external charger such that the magnetic charging field is not radially symmetric. For example, one embodiment includes a primary coil with a plurality of field customization coils distributed radially with respect to the coil. The generated magnetic charging field can be rendered radially asymmetric by selectively activating or disabling the field customization coils in response to data quantifying the coupling between the various implants and the field customization coils in the charger.

Abstract: Improved power circuitry for charging a battery in an implantable medical device is disclosed. The improved power circuitry uses a DC-DC converter positioned between the rectifier and the battery in the implant to be charged, and operates to boost the voltage produced by the rectifier to a higher compliance voltage used to charge the battery. Because the rectifier can now produce a smaller DC voltage, the AC voltage preceding the rectifier (the coil voltage), can also be lessened. Lowering the coil voltage reduces the amount of heat generated by the coil, which reduces the overall heat generated by the implant during receipt of a magnetic charging field from an external charger during a charging session, which improves patient safety. Additionally, a reduced coil voltage means that the external charger can reduce the intensity of the magnetic charging field, which also reduces heat generated in the external charger during the charging session.

Abstract: A burr hole plug comprises a plug base configured for being mounted around a burr hole. The plug base includes an aperture through which an elongated medical device exiting the burr hole may pass. The burr hole plug further comprises a retainer configured for being mounted within the aperture of the plug base. The retainer further includes first and second slidable clamping mechanisms configured for securing the medical devices therebetween within the aperture of the plug base. A method comprises introducing the medical device through the burr hole, mounting a plug base around the burr hole, such that the medical device extends through the plug base aperture, mounting the retainer within the aperture of the plug base, and sliding the first and second clamping mechanisms secure the medical device therebetween.

Abstract: A system for performing a neurostimulation trial comprises an external trial stimulator capable of delivering stimulation energy to a plurality of electrodes carried by one or more stimulation leads. The external trial stimulator is configurable to operate in a plurality of stimulation energy delivery modes to respectively emulate one of different neurostimulator types. The system may further comprise a programmer capable of configuring the external trial stimulator to operate in one of the stimulation energy delivery modes. The programmer may be capable of generating a first programming screen capable of allowing a first set of stimulation parameters to be defined for the first neurostimulator type, and a second programming screen capable of allowing a second set of stimulation parameters to be defined for a second neurostimulator type.

Abstract: A burr hole plug comprises a plug base including a flange configured for being mounted around a burr hole, an aperture through which an elongated medical device may pass, and tabs configured for extending within the cranial burr hole to center the plug base relative to the cranial burr hole. The burr hole plug further comprises a retainer configured for being mounted within the aperture of the plug base to secure the medical device. A method may comprise locating the plug base within a burr hole, such that the tabs are disposed within the burr hole to center the plug base relative to the cranial burr hole, introducing the elongated medical device through the cranial burr hole and into the brain tissue of the patient, mounting the retainer within the aperture of the plug base, and actuating the retainer to secure the medical device.

Abstract: Methods of using unidirectionally propagating action potentials (UPAPs) for vagus nerve stimulation and for certain disorders are provided. Stimulators capable of creating such UPAPs include, but are not limited to, miniature implantable stimulators (i.e., microstimulators), possibly with programmably configurable electrodes.

Abstract: A method for treating a patient may include treating coronary artery disease in combination with angina pectoris and/or the control of angina pain by delivering chemical and/or electrical stimulation pulses to the cardiac and/or nervous tissue of the patient in a coordinated manner. A system for treating a patient suffering from coronary artery disease and angina may include a stimulator that generates at least one pulse in accordance with prescribed parameters, a catheter, a lead, and/or a sensor.

Abstract: A stimulation system is disclosed that may include a stimulator unit coupled to electrode contacts on a cuff. In one embodiment, the cuff may be placed at least partially around a nerve. The stimulation system may include at least two electrode contacts disposed on the cuff such that a distance between the at least two electrode contacts various along a length of the electrode contacts. In another embodiment, a plurality of electrode contacts are disposed on the cuff such that distances between at least one electrode contact within the plurality of electrode contacts and each electrode contact immediately adjacent to the at least one electrode contact are different. The stimulator unit may also be implantable.