Abstract: An intraparenchymal infusion catheter system for delivering drugs or other agents to selected sites in an organism, such as a human, includes a pump that may be implanted or disposed outside the organism. A catheter is coupled to the pump. The catheter comprises a flexible biocompatible tubular portion terminating in a free distal end. The distal end of the catheter bears a rounded tip, a portion of which is slidably disposed within the lumen of the tubular portion. The tip is porous for discharging an agent or drug to a selected site. The tip has a microporosity of less than or equal to 0.22 microns. The tubular portion is composed from a material that will expand from its nominal size when exposed to a stimulus such as heat or a solvent and return to its nominal size when the stimulus is withdrawn. By expanding the tubular portion, a physician can select the amount of the tip that is exposed to the organism, thereby customizing the catheter to the structural size of the selected site within the body.

Abstract: An elongate elastomeric structure having controlled surface texture. Plasma deposition is used to create controlled features, such as ridges, on the external surface of an elongate elastomeric surface, such as the external surface of silicone tubing. The invention has particular applicability in the medical device field, such as the fabrication of implantable leads, catheters, and medical devices incorporating them.

Abstract: A medical electrical lead having a pre-formed atrial portion assuming a distinctive U-shape is disclosed. The U-shaped atrial portion of the lead is configured and dimensioned to cause at least one atrial electrode disposed thereon to be pushed against the right atrial wall or right atrial sinus wall through pushing forces generated by the lead pressing against regions of the heart located near the superior vena cava or the tricuspid valve, and/or through the action of gravity. The lead provides superior coupling of the atrial electrodes thereof to the walls of the right atrium, and may be configured for single pass DDD stimulation of the right atrium and the right ventricle or other portions of the heart such as the coronary sinus or the great cardiac vein.

Abstract: The present invention provides for an encryption apparatus, system, and method in which data from an Implantable Medical Device (IMD) and a data center could be transferred based on a differentiated encryption system. The encryption scheme allows for the differentiation, segregation, and classification of data at required or needed levels of security. Before transfer of the data, either from an IMD or any other part of a support network for the IMDs, the encryption device begins to distinguish the data. The variable data is then classified based on various levels of security having distinct encryption protocols. After classification the data is encrypted based on the data's level of security. The data is then transmitted. Upon being received the data is then segregated based on whether the data is encrypted. The encrypted data is then de-encrypted and interpreted.

Abstract: A lead for brain stimulation comprising a macro segment having a macro electrode for test stimulation and subsequent chronic stimulation, and a micro segment having a micro electrode for single cell recording is described. Methods for using the lead to stimulate brain tissue and to identify functional boundaries within brain tissue are also provided.

Abstract: A method and apparatus for treating Alzheimer's disease is disclosed. The method comprises delivering indomethacin or nonsteroidal anti-inflammatory agents having cyclooxygenase inhibitor action directly to the hippocampus or the lateral ventricle through an implanted catheter. The catheter has a flexible distal end that is implanted directly in the hippocampus or lateral ventricle as the preferred embodiment. The distal end has either a porous tip or a closed end. Where the distal end is closed, or a plurality of elution holes are present indomethacin is delivered to the hippocampus or lateral ventricle through either the porous tip or the elution holes.

Abstract: A medical system having improved telemetry, the medical system featuring a programmer having a programming head. The system provides improved telemetry due to the unique antenna scheme within the programmer head. The antenna scheme utilizes a first antenna and a second antenna, the antennas disposed in a concentric and co-planar manner. This concentric and co-planar disposition permits the programmer head to be of much smaller and, thus, a more portable size than was previously possible. The antenna is further coupled with circuitry or software or both to reduce far field response (noise). The antenna may be constructed using printed circuit board, and thus be integrated with circuitry.

Abstract: An implantable medical lead for stimulation of the sacral nerves comprises a lead body which includes a distal end and a proximal end, and the distal end having at least one electrode contact extending longitudinally from the distal end toward the proximal end. The lead body at its proximal end may be coupled to a pulse generator, additional intermediate wiring, or other stimulation device. The electrode contact of the permanently implantable neurostimulation lead comprises an elongated, flexible, coiled wire or mesh electrode having an exposed electrode length that is adapted to be inserted through the foramen from a posterior access to locate the coiled wire electrode alongside the sacral nerve extending anteriorly and/or posteriorly therefrom. The coiled wire or mesh electrode structure is flexible and bendable to enable its placement through through the foramen and alongside the sacral nerve and to conform to the surrounding nerves and tissue.

Abstract: Methods for sensing or electrical stimulation of body organs or tissues are disclosed wherein a lead conductor wire or filament of a stranded lead conductor generates a radioactive emission when it is fractured sufficiently or is completely broken. The conductor wire or filament is formed of an inner core and an outer sheath surrounding the inner core, wherein the inner core is irradiated or is formed of a radioactive isotope in an alloy that provides an enhanced radiopaque aura when the sheath is fractured and the inner core is exposed. When the conductor wire or filament is intact, the radioactive inner core is fully encased within the outer sheath, and the outer sheath blocks or reduces radioactive emission along its length to a constant, relatively low level. In use, the emission is detected externally to the body, and the detection signifies that a fracture or break has occurred. Such leads preferably comprise cardiac leads for delivering electrical stimulation to the heart, e.g.

Abstract: A body implantable medical apparatus includes circuitry for generating and transmitting a modulated analog data signal. A receiver receives and digitally demodulates the modulated analog signal. An analog-to-digital converting circuit produces an amplitude limited modulated digital signal corresponding to the modulated analog signal. The converting circuit includes an amplifier coupled to a receive antenna and a comparator having an input coupled to the amplifier and an output coupled to a digital demodulator. The digital demodulator demodulates the modulated digital signal to produce a digital information signal, such as a signal containing physiologic sensor data. The digital demodulator includes a digital delay line comprising a plurality of shift registers or, alternatively, a plurality of multiple-stage delay blocks each coupled to a tap selection device.

Abstract: A display driver circuit for driving a flat panel display including circuitry for detecting integrity of bonding of outputs of the driver circuit to the display. The bond integrity detecting circuitry includes a test mode current source which applies current to the output being tested to raise its voltage to a threshold level. At a defined sampling time following initiation of application of the test mode current, the voltage on the output being tested is compared to the threshold level, and the result of the comparison is stored and output from the driver circuit. If the voltage of the output has not reached the threshold level at the defined sampling time, the output connection is determined to be good.

Abstract: A conical depression for guiding a hypodermic needle into a desired location and having a hole at the center for limiting the maximum needle diameter that can be used to access that location. The diameter of the hole prevents access by needles having a diameter greater than the diameter of the hole. The conical depression has a smooth surface and an angle such that needles that are inserted into the conical depression misaligned with the hole will be guided to the hole without damaging the tip of the hypodermic needle.

Abstract: A system for communicating with a medical device implanted in an ambulatory patient and for locating the patient in order to selectively monitor device function, alter device operating parameters and modes and provide emergency assistance to and communications with a patient. The implanted device includes a telemetry transceiver for communicating data and operating instructions between the implanted device and an external patient communications control device that is either worn by or located in proximity to the patient within the implanted device transceiving range. The control device preferably includes a communication link with a remote medical support network, a global positioning satellite receiver for receiving positioning data identifying the global position of the control device, and a patient activated link for permitting patient initiated personal communication with the medical support network.

Abstract: An implantable lead is provided with at least one extendable member to position therapy delivery elements, which may be electrodes or drug delivery ports, after the lead has been inserted into the body. The lead may formed as a resilient element which is contained in a retainer tube that may be removed to permit the lead to deploy. Alternatively, a non-resilient lead may be provided with a slotted retainer tube. A series of mechanical linkages for expanding and retracting the lead within the human body may be actuated with various mechanisms. A control system may be provided for closed-loop feedback control of the position of the extendable members. The invention also includes a method for expanding an implantable lead in situ.

Abstract: Apparatus, systems and methods for coupling components of an implantable medical device that are contained within separate sterile packages together and testing operation thereof prior to chronic implantation are disclosed. In particular, testing of the integrity of the lead conductors and other electrical components coupled therewith and the testing and calibration of an implantable sensor, e.g., an implantable pressure sensor, coupled to a programmable, implantable hemodynamic monitor (IHM) or implantable pulse generator (IPG) while in respective sterile packages are disclosed. The lead and IPG/IHM sterile packages are provided with package connectors that couple the terminals of the IPG/IHM and lead to external package connector arrays. The package connector arrays are coupled together, and a programmer is employed to downlink telemetered commands to the IPG or IHM to test the sensor and/or lead conductors and uplink via telemetery the results to the programmer for display.

Abstract: A method and apparatus including conditional add and conditional add/subtract instructions are provided for use in the instruction set of a medical device instruction processor. More specifically, the conditional add and add/subtract instructions are provided to add two operands if a predetermined condition is satisfied within the instruction processor hardware. Additionally, the conditional add/subtract instruction may be used to subtract one operand from another operand if the predetermined condition is not satisfied. These instructions are adapted for use in implementing an efficient, interruptible, firmware-controlled multiplication or division mechanism. The inventive system allows multiplication or division operations to be interrupted at various intermediate points during the multiplication or division operation to thereby reducing interrupt latency.

Abstract: A stent (1) is provided for having variable flexibility and stiffness along its length. The stent (1) comprises portions (5, 7, 9, 11, 13, 15) of the stent having different bending and durability characteristics, and may be fabricated, using any of a variety of methods out of any of a variety of materials.

Abstract: An implantable electrical lead having at least two mutually insulated electrical components that are separated by a portion of the lead's body fabricated of a plant, extensible biocompatible insulated material. An extensible conductor extends from the proximal end of the lead body to a first one of the electrical components, and a second, inextensible conductor extends from the proximal end of the lead body to a second one of the electrical components. An inextensible reinforcement member is coupled to the inextensible conductor and extends distally from the second electrical component to the first electrical component and is coupled mechanically to the first electrical component.

Abstract: The present invention provides a branching endoluminal prosthesis for use in branching body lumen systems which includes a trunk lumen and first and second branch lumens. The prostheses comprises a radially expandable tubular trunk portion having a prosthetic trunk lumen, and radially expandable tubular first and second branch portions with first and second prosthetic branch lumens, respectively. A radially expandable tubular Y-connector portion provides fluid communication between the prosthetic trunk lumen and the first and second prosthetic branch lumens.

Abstract: An implantable lead which has an increased resistance to fracture and has the capability of continued function after fracture of a conductor. The lead is provided with a coiled conductor which may be monofilar or multifilar and which extends along the length of the lead, running from an electrical connector at the proximal end of the lead to an electrode at or near the distal end of the lead. In addition, the lead is provided with a stranded conductor which is electrically coupled to the coiled conductor at point along the lead body located proximal to the point of expected breakage of the coiled conductor and at a point along the lead body located distal to the point of expected breakage. The proximal and distal ends of the stranded conductor in some embodiments are also mechanically coupled to the coiled conductor.