Abstract: Communication systems and methods for dynamically controlling the power wirelessly delivered by a remote reader unit to separate sensing device, such as a device adapted to monitor a physiological parameter within a living body, including but not limited to intraocular pressure, intracranial pressure (ICP), and cardiovascular pressures that can be measured to assist in diagnosing and monitoring various diseases. The communication method entails electromagnetically delivering power from at least one telemetry antenna within the reader unit to at least one telemetry antenna within the sensing device, and controlling the power supplied to the sensing device within a predetermined operating power level range of the sensing device.

Abstract: A system for monitoring blood pressure and other physiologic parameters is provided. The system is designed such that it can be delivered to the patient with ease and minimal invasion. The system contains at least one self contained implantable sensing device consisting of a sensor, an electrical circuit for signal conditioning and magnetic telemetry, a biocompatible outer surface and seal, an anchoring method, and an external readout device. The implant is small in size so that it may be delivered to the desired location and implanted using a catheter, although direct surgical implantation is also possible. The circuit, sensor, and antenna for telemetry are packaged together and sealed hermetically to the biologic environment. The larger readout unit remains outside the body but proximal to the implant for minimizing communication distance.

Abstract: A microelectromechanical system (MEMS) device and method for operating the device to determine a property of a fluid. The device has a tube that extends from a base and is spaced apart from a substrate surface for vibrational movement in a plane normal to the surface. The tube defines a continuous internal passage having a fluid inlet and fluid outlet fluidically connected to the base. A cantilevered member attached to a distal portion of the tube opposite the base is configured for vibrational movement relative to the distal portion. A drive electrode operable to induce vibrational movements in the tube and cantilevered member is disposed on the substrate surface. Sensing electrodes are disposed on the substrate surface for sensing Coriolis-induced deflections of the tube when vibrated, generating outputs from which a property of a fluid flowing through the tube can be determined.

Abstract: A microelectromechanical system (MEMS) device and a method for operating the device to determine at least one property of a fluid. The device includes a base on a substrate and a tube structure extending from the base and spaced apart from a surface of the substrate. The tube structure includes at least one tube portion and more preferably at least a pair of parallel tube portions substantially lying in a plane, at least one continuous internal passage defined at least in part within the parallel tube portions, and an inlet and outlet of the internal passage fluidically connected to the base. A drive element is operable to induce vibrational movement in the tube structure in a plane of the tube structure and induce resonant vibrational movements in the tube portions. A sensing element senses the deflections of the tube portions when the tube structure is vibrated with the drive element.

Abstract: An anchor and procedure for placing a medical implant, such as for monitoring physiological parameters. The anchor includes a central body in which a medical implant can be received. Arms and members extend radially from first and second ends, respectively, of the central body. Each member defines a leg extending toward distal portions of the arms to provide a clamping action. The anchor and its implant are placed by coupling first and second guidewires to first and second portions of the anchor, placing an end of a delivery catheter in a wall where implantation is desired, inserting the anchor in the catheter with the guidewires to locate the anchor within the wall, deploying the arms of the anchor at one side of the wall followed by deployment of the members at the opposite side of the wall, and thereafter decoupling the guidewires from the anchor.

Abstract: A microfluidic device for assessing properties of a fluid. The device utilizes a microtube capable of different vibration modes for promoting certain performance and/or structural aspects of the device. The microtube is supported by a base so as to be spaced apart from a substrate surface. The microtube has a peripheral portion surrounding the base, arms supporting the peripheral portion from the base, and a continuous internal microchannel having at least first and second microchannel portions. Each microchannel portion defines a separate flow route, and each flow route originates at the base, continues through a portion of the peripheral portion, and returns to the base. The first and second microchannel portions are fluidically connected to inlet and outlet ports, respectively, within the base. Vibration of the microtube is induced and sensed by driving and sensing elements. Fluid properties are determined from outputs of the sensing elements.

Abstract: A process for fabricating multiple microfluidic device chips. The process includes fabricating multiple micromachined tubes in a semiconductor device wafer. The tubes are fabricated so that each tube has an internal fluidic passage and an inlet and outlet thereto defined in a surface of the device wafer. The device wafer is then bonded to a glass wafer to form a device wafer stack, and so that through-holes in the glass wafer are individually fluidically coupled with the inlets and outlets of the tubes. The glass wafer is then bonded to a metallic wafer to form a package wafer stack, so that through-holes in the metallic wafer are individually fluidically coupled with the through-holes of the glass wafer. Multiple microfluidic device chips are then singulated from the package wafer stack. Each device chip has a continuous flow path for a fluid therethrough that is preferably free of organic materials.

Abstract: A telemetric sensing system for monitoring physiological parameters for diagnosis and treatment of congestive heart failure in a patient. This system includes one or more implantable sensing devices implanted in a cavity of the patient's cardiovascular system, and a non-implantable reader unit. The implantable sensing device has an inductor and at least one sensor with an option of having electronic components, as well as a mechanism for anchoring the device inside the patient's body. The external readout device has at least one inductor coil with a telemetric device that provides for at least one of electromagnetic telecommunication and wireless powering of the sensing device. This wireless system provides a means for effective monitoring, management and tailoring of treatments for patients suffering from congestive heart failure as well as many other diseases.

Abstract: A process for producing a micromachined tube (microtube) suitable for microfluidic devices. The process entails isotropically etching a surface of a first substrate to define therein a channel having an arcuate cross-sectional profile, and forming a substrate structure by bonding the first substrate to a second substrate so that the second substrate overlies and encloses the channel to define a passage having a cross-sectional profile of which at least half is arcuate. The substrate structure can optionally then be thinned to define a microtube and walls thereof that surround the passage.

Abstract: A microfluidic device and method for assessing properties of a fluid. The device includes a base supported by a substrate and a tube extending from the base and spaced apart from the substrate surface. The tube has an internal passage, first and second portions adjacent the base and defining, respectively, an inlet and outlet of the passage, and a distal portion. A drive electrode is located on the substrate surface adjacent the distal portion of the tube. Sensing electrodes are located on the substrate surface adjacent the first and second portions of the tube, and are adapted for sensing deflections of the first and second portions when vibrated with the drive electrode and from which the fluid property is determined. A pair of electrodes is located on the substrate surface between the drive and sensing electrodes, and are operated to enhance the performance of the microfluidic device, such as by supplementing the drive or sensing electrodes.

Abstract: A microfluidic device a micromachined freestanding member adapted to sense one or more properties of a fluid flowing through the freestanding member. The freestanding member is supported by a substrate and spaced apart and separated from the substrate to enable the freestanding member to move relative to the substrate under the influence of a vibration-inducing element. Movement of the freestanding member relative to the substrate is then sensed by a sensing element. The freestanding member has an inlet, an outlet, an internal passage that fluidically couples the inlet and outlet, and a wall that defines and separates first and second passage portions of the internal passage that are arranged in fluidic series so that a fluid flowing through the internal passage flows through the first and second passage portions in opposite directions.

Abstract: A system for monitoring blood pressure and other physiologic parameters is provided. The system is designed such that it can be delivered to the patient with ease and minimal invasion. The system contains at least one self contained implantable sensing device consisting of a sensor, an electrical circuit for signal conditioning and magnetic telemetry, a biocompatible outer surface and seal, an anchoring method, and an external readout device. The implant is small in size so that it may be delivered to the desired location and implanted using a catheter, although direct surgical implantation is also possible. The circuit, sensor, and antenna for telemetry are packaged together and sealed hermetically to the biologic environment. The larger readout unit remains outside the body but proximal to the implant for minimizing communication distance.

Abstract: A fluid sensing system and method for sensing properties of a flowing fluid. The system and method entail a microfluidic device having a micromachined tube supported above a substrate, a tube passage within a freestanding portion of the tube, an inlet and outlet in fluidic communication with the tube passage and an exterior of the microfluidic device, elements for vibrating the freestanding portion of the tube, and elements for sensing movement of the freestanding portion of the tube so as to measure the vibration frequency and/or deflection of the freestanding portion and produce therefrom at least one output corresponding to a property of a fluid flowing through the tube passage. The system and method further entail placing the microfluidic device in a flowing fluid so that a fraction of the fluid enters the tube passage, and processing the output of the device to compute a property of the fluid.

Abstract: An anchor for an implantable sensing device, a sensor unit formed by the anchor and sensing device, and a surgical procedure for implanting the sensor unit for monitoring a physiological parameter within a cavity of a living body, such as an intracranial physiological property. The anchor includes a shank portion and a head portion. The shank portion defines a distal end of the anchor and has a bore defining an opening at the distal end. The head portion defines a proximal end of the anchor and has a larger cross-sectional dimension than the shank portion. The sensor unit comprises the anchor and the sensing device placed and secured within the bore of the anchor so that a sensing element of the sensing device is exposed for sensing the physiological parameter within the cavity.

Abstract: An implantable system and method for deep brain stimulation (DBS) treatments. The implantable system is sufficiently small and self-contained to enable implantation of the entire system within the brain, or optionally within the brain and the surrounding tissue. The system comprises an implantable inductor on which a voltage is induced when subjected to an electromagnetic field, and an implantable device comprising a housing, stimulating elements at an exterior surface of the housing, and electronics within the housing and electrically connected to the implantable inductor. The electronics produces a brain-stimulating current from the voltage induced on the implantable inductor and then delivers the brain-stimulating current to the stimulating elements. Deep brain stimulation is performed by subjecting the inductor to an electromagnetic field to induce a voltage on the inductor that powers the electronics to produce and deliver the brain-stimulating current to the stimulating elements.

Abstract: A system for monitoring a charge-based physiological parameter within an internal organ of a living body, and a sensor adapted to be implanted in the living body and an organ therein. The sensor includes sensing elements adapted to sense the charge-based physiological parameter within the organ, and the sensing elements include at least first and second sensing elements that are electrically conductive, aligned, spaced apart and exposed at the exterior of the sensor. The sensor further includes a device for passing an alternating current from the first to the second sensing elements through an ionic solution contacting the sensing elements. The sensor also includes a device for generating a signal corresponding to the impedance of the ionic solution based on the alternating current.

Abstract: A microfluidic device and sensing method that utilize a resonating tube configured to have sufficient sensitivity to be capable of sensing the volume of a gas present as bubbles in a liquid or the flow rate and/or density of a gas or gas mixture flowing through the tube. The tube has a freestanding tube portion supported above a surface of a substrate so as to be capable of vibrating in a plane normal to the surface of the substrate. As a gas-containing fluid flows through an internal passage of the tube, a drive signal vibrates the freestanding tube portion at a resonant frequency thereof. Coriolis-induced deflections of the freestanding tube portion are sensed relative to the substrate to produce an output corresponding to the sensed deflections, and the drive signal and/or the output are assessed to determine the volume, density and/or flow rate of the gas of the gas-containing fluid.

Abstract: A sensing and analysis system, method, and network that make use of a very portable and compact sensor unit and a physically separate electronic unit that serves to power and control the sensor unit, process and optionally display the output of the sensor unit, and transmit the sensor output to other locations, such as over a network. The sensor unit includes a housing, a sensing element within the housing and responsive to an input, and electronic circuitry within the housing and in communication with the sensing element to produce an electrical output based on an output signal generated by the sensing element. A communication providing device delivers instructions generated by the electronic unit to the sensor unit and delivers the electrical output from the sensor unit to the electronic unit.

Abstract: A minimally-invasive surgical procedure for monitoring a physiological parameter within an internal organ of a living body. The procedure entails making a first incision in the body to enable access to the organ. An endoscopic instrument is then inserted through the first incision and a second incision is made therewith through an external wall of the organ and into the internal cavity thereof. A sensing unit is placed in the second incision such that the second incision is occluded by the unit and a proximal end of the unit is outside the organ. The unit includes a sensing device having a sensing element adapted to sense the physiological parameter within the organ, and an anchor to which the sensing device is secured. The first incision is closed, after which a readout device outside the body telemetrically communicates with the sensing device to obtain a reading of the physiological parameter.

Abstract: A microfluidic device for assessing properties of a fluid. The device utilizes a microtube capable of different vibration modes for promoting certain performance and/or structural aspects of the device. The microtube is supported by a base so as to be spaced apart from a substrate surface. The microtube has a peripheral portion surrounding the base, arms supporting the peripheral portion from the base, and a continuous internal microchannel having at least first and second microchannel portions. Each microchannel portion defines a separate flow route, and each flow route originates at the base, continues through a portion of the peripheral portion, and returns to the base. The first and second microchannel portions are fluidically connected to inlet and outlet ports, respectively, within the base. Vibration of the microtube is induced and sensed by driving and sensing elements. Fluid properties are determined from outputs of the sensing elements.