Abstract: An external transmitter circuit drives an implantable neural stimulator having an implanted coil from a primary coil driven by a power amplifier. For efficient power consumption, the transmitter output circuit (which includes the primary coil driven by the power amplifier inductively coupled with the implanted coil) operates as a tuned resonant circuit. When operating as a tuned resonant circuit, it is difficult to modulate the carrier signal with data having sharp rise and fall times without using a high power modulation amplifier. Sharp rise and fall times are needed in order to ensure reliable data transmission. To overcome this difficulty, the present invention includes an output switch that selectively inserts a resistor in the transmitter output coil circuit in order to de-tune the resonant circuit only during those times when data modulation is needed. Such de-tuning allows sharp rise and fall times in the data modulation without the need for using a high power modulation amplifier.

Abstract: An implantable neural stimulation system, such as an auditory Fully Implantable System (FIS), includes: (1) an implanted device capable of providing desired tissue or nerve stimulation; and (2) a remote control unit that provides a mechanism for readily controlling the implant device. The remote control unit uses a first signal path to send signals to the implant device, and a second signal path to receive signals from the implant device. The combination of these two signal paths provides a full-duplex channel between the remote control unit and the implant device through which appropriate control and status signals may be sent and received. In one embodiment, the first signal path comprises an audio signal path through which audio control signals, e.g., a tone sequence or a 32-bit word FSK modulated between 300 and 1200 Hz, are sent; and the second signal path comprises a RF signal path through which a BPSK, QPSK or FM modulated RF signal is received.

Abstract: An implantable pump system includes: (1) an implantable pump having separate chambers or reservoirs, at least one of which is coupled to the pump so as to allow a programmable rate of delivery of the medication stored in the pump chamber or reservoir, the other chambers or reservoirs of which are at least capable of delivery of a bolus via a pressurized, and potentially independently programmable chamber or pumping mechanism; (2) a patient controller that enables the actuation of the pump so as to administer a bolus or programmed rate of the first, second, third, . . . or nth medication contained in the independent chambers or reservoirs coupled to the pump; and (3) a catheter having two or more reservoir-specific inlet ports directed into respective lumens of the catheter.

Abstract: An external transmitter circuit drives an implantable neural stimulator having an implanted coil from a primary coil driven by a power amplifier. For efficient power consumption, the transmitter output circuit (which includes the primary coil driven by the power amplifier inductively coupled with the implanted coil) operates as a tuned resonant circuit. When operating as a tuned resonant circuit, it is difficult to modulate the carrier signal with data having sharp rise and fall times without using a high power modulation amplifier. Sharp rise and fall times are needed in order to ensure reliable data transmission. To overcome this difficulty, the present invention includes an output switch that selectively inserts a resistor in the transmitter output coil circuit in order to de-tune the resonant circuit only during those times when data modulation is needed. Such de-tuning allows sharp rise and fall times in the data modulation without the need for using a high power modulation amplifier.

Abstract: A bionic ear cochlear stimulation system has the capability to stimulate fast enough to induce stochastic neural firing, thereby acting to restore “spontaneous” neural activity. Such neurostimulation involves the use of a high rate pulsitile stimulation signal that is amplitude modulated with sound information. Advantageously, by using such neurostimulation, a fitting system may be utilized that does not normally require T-level threshold measurements. T-level threshold measurements are not required in most instances because the high-rate pulsitile stimulation, even though at levels that would normally be a sub-threshold electrical stimulus, is able to modulate neural firing patterns in a perceptible way.

Abstract: An implantable system includes a plurality of implantable devices that are detachably coupled to each other. Each implantable device of the system includes: (1) an hermetically-sealed case housing electronic components; (2) feedthru terminals mounted to a wall of the hermetically-sealed case adapted to allow electrical contact from a location outside the hermetically-sealed case with the electronic components housed inside the hermetically-sealed case; (3) a coil external to the hermetically-sealed case attached to the feedthru terminals; (4) a flexible molding bonded to the hermetically-sealed case, and wherein the coil is embedded within or otherwise attached to the flexible molding; and (5) engagement means for engaging the flexible molding with a flexible molding of another implantable device of the implantable system. Such engagement means also aligns the coils of the implantable devices that are thus engaged with the engaging means to allow electromagnetic coupling to occur between the aligned coils.

Abstract: An insertion tool uses a stylet wire to help guide an electrode system into a cochlea. The insertion tool includes three main elements or parts: a handle, a guide and a slider. The handle is made from light stainless steel tube flattened in front with a machined slot. The guide consists of a plurality of metal tubes, fixed to each other within a holding bracket. In one embodiment, the slider includes a stabilizer wire, a long stylet wire, and a short stylet wire. During the assembly process, the stabilizer and stylet wires are inserted into respective tubes of the guide and the end of the stabilizer wire is bent to form an offset. The electrode system is loaded onto the tool by inserting the short stylet wire into a holder that supports the electrode lead.

Abstract: A multicontact electrode array suitable for implantation in living tissue includes a distal end having multiple spaced-apart ring or band electrode contacts carried on a flexible tube carrier. Each ring electrode contact is laser welded to a respective wire tip that has a multi-helix orientation on the inside of a separation tube. The center of the multi-helix wire defines a lumen wherein a positioning stylet, or other suitable positioning tool, may be removably inserted when the electrode array is implanted. The method of making the multicontact electrode array includes, as an initial step, winding lead wires around a suitable mandrel so as to form a multi-helix configuration. (Alternatively, the wire may be purchased in a multiwire pre-wound configuration that defines a lumen, in which case the mandrel is slipped inside the lumen.) Then, at a distal end of the electrode, each wire within the multi-helix winding is unwound so as to protrude out from the winding.

Abstract: A method of controlling an implantable neural stimulation system, such as an auditory Fully Implantable System (FIS), uses a first signal path to send signals to the implant device, and a second signal path to receive signals from the implant device. The combination of these two signal paths provides a full-duplex channel between the remote control unit and the implant device through which appropriate control and status signals may be sent and received. In one embodiment, the first signal path comprises an audio signal path through which audio control signals, e.g., a tone sequence or a 32-bit word FSK modulated between 300 and 1200 Hz, are sent; and the second signal path comprises a RF signal path through which a BPSK, QPSK or FM modulated RF signal is received. The full-duplex channel allows operation of the remote control unit, i.e., allows signals to be successfully sent to and received from the implant device, from as far away as 45–60 cm from the implant device.

Abstract: A cochlear implant system, or other neural stimulation system, has the capability to stimulate fast enough to induce stochastic neural firing so as to restore “spontaneous” neural activity. The stimulation rate applied to the more distally-located electrodes of an electrode array connected to the implant system is reduced from the stimulation rate applied to the more proximally-located electrodes. Thus, in the case of a cochlear implant system, the apically-located regions within the cochlea are stimulated at a reduced rate in order to conserve power. Pulse widths of the reduced-rate pulses may further be increased, and amplitudes reduced, to further conserve power. As needed, a low-level random conditioner stimulation signal may be applied to the apical regions of the cochlea in order to ensure the occurrence of random neural firings.

Abstract: A curved paddle electrode allows the electrode to be placed over a relatively flat or oval shaped nerve bundle attached to fascia tissue without having to separate the nerve bundle from the fascia tissue. The electrode includes at least one suture hole that allows the electrode to be held in place over the nerve bundle through a clip-on stitch, or equivalent. In one embodiment, the curved paddle electrode provides a tripolar electrode configuration that allows three spaced-apart parallel electrode contacts to be positioned transverse to a target nerve bundle. Such electrode configuration allows bipolar or tripolar stimulation to occur. Other embodiments employ less or more than three electrode contacts. A preferred application of the curved paddle electrode is for the treatment of erectile dysfunction (ED), where the electrode is placed over the neurovascular bundle attached to the rectal fascia tissue near the rectum.

Abstract: Interelectrode impedance or electric field potential measurements are used to determine the relative orientation of one lead to other leads in the spinal column or other body/tissue location. Interelectrode impedance is determined by measuring impedance vectors. The value of the impedance vector is due primarily to the electrode-electrolyte interface, and the bulk impedance between the electrodes. The bulk impedance between the electrodes is, in turn, made up of (1) the impedance of the tissue adjacent to the electrodes, and (2) the impedance of the tissue between the electrodes. In one embodiment, the present invention makes both monopolar and bipolar impedance measurements, and then corrects the bipolar impedance measurements using the monopolar measurements to eliminate the effect of the impedance of the tissue adjacent the electrodes. The orientation and position of the leads may be inferred from the relative minima of the corrected bipolar impedance values.

Abstract: A fully implantable cochlear prosthesis includes (1) an implantable hermetically sealed case wherein electronic circuitry, including a battery and an implantable microphone, are housed, (2) an active electrode array that provides a programmable number of electrode contacts through which stimulation current may be selectively delivered to surrounding tissue, preferably through the use of appropriate stimulation groups, and (3) a connector that allows the active electrode array to be detachably connected with the electronic circuitry within the sealed case. The active electrode array provides a large number of both medial and lateral contacts, any one of which may be selected to apply a stimulus pulse through active switching elements included within the array. The active switching elements included within the array operate at a very low compliance voltage, thereby reducing power consumption.

Abstract: A deep brain stimulation (DBS) system (10) provides a multiplicity of stimulation channels through which stimulation may be delivered deep within the brain of the patient. The DBS system is powered by a rechargeable battery (27). In one embodiment, the system has four channels driving sixteen electrodes (32). The DBS system is easily programmed for use by a clinician using a clinician programming system (60), and further affords a simple but highly advanced hand held programmer (50) control interface through which the patient may easily change stimulation parameters within acceptable limits. The DBS system (10) includes a small, implantable pulse generator (20) that is small enough to be implanted directly in the cranium of the patient, thereby eliminating the long lead wires and tunneling procedures that have been used in the past.

Abstract: An implantable pulse generator includes a current steering capability that allows a clinician or patient to quickly determine a desired electrode stimulation pattern, including which electrodes of a group of electrodes within an electrode array should receive a stimulation current, including the amplitude, width and pulse repetition rate of such current. Movement of the selected group of electrodes is facilitated through the use of remotely generated directional signals, generated by a pointing device, such as a joystick. As movement of the selected group of electrodes occurs, current redistribution amongst the various electrode contacts takes place. The redistribution of stimulus amplitudes utilizes re-normalization of amplitudes so that the perceptual level remains fairly constant. This prevents the resulting paresthesia from falling below the perceptual threshold or above the comfort threshold.

Abstract: A spinal cord stimulation (SCS) system includes multiple electrodes, multiple, independently programmable, stimulation channels within an implantable pulse generator (IPG) which channels can provide concurrent, but unique stimulation fields, permitting virtual electrodes to be realized. The SCS system includes a replenishable power source (e.g., rechargeable battery), that may be recharged using transcutaneous power transmissions between antenna coil pairs. An external charger unit, having its own rechargeable battery can be used to charge the IPG replenishable power source. A real-time clock can provide an auto-run schedule for daily stimulation. An included bi-directional telemetry link in the system informs the patient or clinician the status of the system, including the state of charge of the IPG battery. Other processing circuitry in the IPG allows electrode impedance measurements to be made. Further circuitry in the external battery charger can provide alignment detection for the coil pairs.

Abstract: A cochlear electrode array is adapted for implantation within the basal end of the scala tympani duct of a human cochlea. A first embodiment of the cochlear electrode array (10) comprises a skinny, elongate carrier (12) of from 6-8 mm in length. Four to eight spaced-apart electrode contacts (14) reside along one of the flat sides of the carrier, each of which is connected to a respective wire (22) embedded within the carrier. The wires exit a proximal end of the carrier via a wire bundle. The wire bundle, in turn, is connectable to an implantable cochlear stimulator (ICS) or equivalent pulse generator. The electrode array (10) is inserted into the relatively straight portion of the basal end of the scala tympani duct of the cochlea through a small slit (42) made in the round window membrane that separates the cochlea from the middle ear. The slit is oriented so as to place the electrode contacts facing the modiolar wall (32).

Abstract: A method of making an implantable electrode array, adapted for insertion into a cochlea, includes the steps of: (a) forming electrode contact pieces made from a precious, biocompatible material into a desired shape; (b) attaching the electrode contact pieces to a foil sheet made from a non-toxic but chemically-active metal; (c) connecting a wiring system to the metal contact pieces; (d) molding a flexible polymer carrier around the electrode contact pieces and wiring system while such are held in place by the foil sheet; and (e) etching away the foil sheet, leaving the electrode contact pieces exposed at a surface of the molded polymer carrier. The exposed electrode contacts are made so as to have a shape, geometry, or makeup that aids in controlling the current flow and current density associated with the electrode contact as a function of position on the electrode contact.

Abstract: A combination, voltage converter circuit for use within an implantable device, such as a microstimulator, uses a coil, instead of capacitors, to provide a voltage step up and step down conversion functions. The output voltage is controlled, or adjusted, through duty-cycle modulation. In accordance with one aspect of the invention, applicable to implantable devices having an existing RF coil through which primary or charging power is provided, the existing RF coil is used in a time-multiplexing scheme to provide both the receipt of the RF signal and the voltage conversion function. This minimizes the number of components needed within the device, and thus allows the device to be packaged in a smaller housing or frees up additional space within an existing housing for other circuit components. In accordance with another aspect of the invention, the voltage up/down converter circuit is controlled by a pulse width modulation (PWM) low power control circuit.

Abstract: An implantable neural stimulation system, such as an auditory Fully Implantable System (FIS), includes: (1) an implanted device capable of providing desired tissue or nerve stimulation; and (2) a remote control unit that provides a mechanism for readily controlling the implant device, i.e., for selectively adjusting certain stimulation parameters associated with the tissue stimulation of the implanted device. The remote control unit uses a first signal path to send signals to the implant device, and a second signal path to receive signals from the implant device. The combination of these two signal paths provides a full-duplex channel between the remote control unit and the implant device through which air appropriate control and status signals may be sent and received. In one embodiment, the first signal path comprises an audio signal path through which audio control signals, e.g.