Abstract: An electrode array suitable for insertion into the cochlea has a drug delivery channel therein. In a preferred embodiment, electrical stimuli may be applied near the modiolar wall of the cochlea via spaced-apart electrode contacts embedded along a front edge of a flexible carrier, which flexible carrier comprises the body of the electrode array. The front edge, and hence the electrode contacts, may be held against the modiolar wall by a flexible positioner placed on the back side of the flexible carrier. Drugs may be delivered deep into the cochlea through the drug delivery channel that passes longitudinally through the center of the flexible carrier. In an alternative embodiment, the drug delivery channel may be included within the positioner.

Abstract: A fully implantable cochlear implant system (170) and method includes an implantable cochlear stimulator (ICS) unit (212) that is connected to an implantable speech processor (ISP) unit (210). Both the ISP unit and the ICS unit reside in separate, hermetically-sealed, cases. The ICS unit has a coil (220) permanently connected thereto through which magnetic or inductive coupling may occur with a similar coil located externally during recharging, programming, or externally-controlled modes of operation. The ICS unit further has a cochlear electrode array (114) permanently connected thereto via a first multi-conductor cable (116). The ICS unit 212 also has a second multi-conductor cable (222) attached thereto, which second cable contains no more than five conductors. The second cable is detachably connected to the ISP unit via a connector (224) located on the case of the ISP unit.

Abstract: An implantable electrode array, adapted for insertion into a cochlea, provides a multiplicity of exposed electrode contacts, each having 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. In one embodiment, the shape or geometry of the exposed electrode contact controls the contact surface of the electrode contact in a way that varies the current flow and current density as a function of surface area position on the electrode, thereby focusing most of the current to flow through the center of the electrode contact. In another embodiment, the electrode contact is coated with a dielectric or other material that controls the surface contact impedance as a function of distance from the center of the electrode, again focusing most of the current flow through the center of the electrode contact.

Abstract: A hair clip for use with a cochlear implant system retains a headpiece assembly, including a transmitting coil, in an aligned position relative to an implanted stimulator. In one embodiment, the hair clip provides a retention system that uses a magnet which forms part of the transmitting coil. A comb or plurality of prongs forms part of the retention system. In another embodiment, the comb has central teeth that are made from ferromagnetic material, and typically also has a non-central teeth that are made from non-ferromagnetic material. The comb is placed and secured in the patient's hair over the area where a cochlear implant is implanted. The transmitting coil is then placed next to the comb, and the magnet within the transmitting coil attaches to the ferromagnetic teeth of the comb.

Abstract: The present invention provides a fully implantable cochlear implant system (FICIS) that allows various configurations of different modules to be combined so as to meet the needs of a particular patient, including very young patients. At least three main modules are used in the FICIS, including (1) a small implantable cochlear stimulator (ICS) module, with permanently attached cochlear electrode array; (2) an implantable speech processor (ISP) module, with integrated microphone and rechargeable battery; and (3) an external module. In one embodiment, the external module may comprise an external speech processor (ESP) module. In another embodiment, the external module may comprise an external battery charger (EBC) module. The ICS and ISP modules are configured to facilitate long time reliable use of the ICS module, e.g., for the lifetime of the patient, and low-risk, relatively easy replacement of the ISP module.

Abstract: An inflatable cochlear electrode array adapted for insertion into a human cochlear includes a flexible carrier on which a multiplicity of spaced-apart electrode contacts are carried, preferably along one side, e.g., a medial side, of the carrier. The flexible carrier also includes an inflatable compartment or section. In one embodiment, the inflatable section is located at the distal tip of the electrode array on a side of the flexible carrier that is opposite the electrode contacts. In another embodiment, the inflatable compartment or section is located along at least one half of the full length of the flexible carrier, forming a spine. In either embodiment, the electrode is readily inserted into the cochlea to a desired depth while the inflatable compartment or section remains in a deflated state. Thereafter, a desired modiolus-hugging position is achieved by inflating the inflatable compartment or section by injecting therein a suitable biocompatible fluid.

Abstract: A hearing aid system provides acoustic modulation of the fluid within the cochlea of the inner ear corresponding to a first frequency range of sensed acoustic signals, e.g., lower-to-middle frequencies of the audible range, and electrical stimulation of the cochlea corresponding to a second frequency range, e.g., high frequencies of the audible range. In a preferred implementation, a short electrode/transducer array is provided for use with the hearing system. Such array is adapted to be inserted into the basal region of the scala tympani of the cochlea. The electrode/transducer array includes a plurality of spaced-apart electrode contacts through which electrical stimulation is provided to stimulate ganglion cells located in the basal region of the cochlea, which cells are responsible for perceiving the higher frequencies of the acoustic energy.

Abstract: A stapedius electrode attaches to or is embedded within the stapedius muscle (20) at a point near where the stapedius muscle is visible as it exits a bony channel (30) within the middle ear. In one embodiment, the electrode is made from a biocompatible metal wire formed into a flat blade (102) having a sharp tip (104) and serrations (103) along one edge. An insulated lead attaches electrically and mechanically to the blade. Such attachment may be made by welding and wrapping the insulated lead at one end of the wire around the body of the electrode and protecting such weld and securing such wrappings with a coating or blob of epoxy. During implantation of the electrode, the electrode blade is inserted through a small slot made in the muscle tissue. Alternatively, the electrode may be inserted alongside the muscle tissue through an opening in the bony wall as it passes through the bony channel, with a tip of the electrode protruding from the bony channel.

Abstract: A paddle-type electrode or electrode array is implantable like a percutaneously inserted lead, i.e., without requiring major surgery, but once inserted, expands to provide a platform for many electrode configurations. The electrode array is provided on a flexible, foldable, subcarrier or substrate. Such subcarrier or substrate is folded, or compressed. during implantation, thereby facilitating its insertion using simple, well-known percutaneous implantation techniques. Once implanted, such subcarrier or substrate expands, thereby placing the electrodes in a desired spaced-apart positional relationship, and thus achieving a desired electrode array configuration. A memory element is used within the subcarrier or substrate which causes the electrode array to expand or unfold to a desired unfolded or expanded state after it has been implanted while in a folded up or compressed state.

Abstract: A multi-output connector for use with an implantable neurostimulator, or similar implantable stimulator, is described. The connector includes three main components: an output bracket (10), a receiver (20), and a clamp (30). The output bracket forms part of the stimulator and is typically made from a hard polymer, such as epoxy resin. It has a T-shaped cross section, and has an array of metal contacts placed on both sides of the base of the “T”. The receiver is made from a soft polymer, such as silicone rubber, and has a T-slot formed therein adapted to match the T-shaped cross-section of the output bracket. Contact pins are formed in the side walls of the receiver so as to make electrical contact with the metal contacts of the output bracket when the receiver is placed over the bracket. The clamp is made from metal in the form of a U-shape and fits over the top of the receiver 20 to apply compression to both side of the receiver.

Abstract: An implantable space-filling electrode system, adapted for insertion into a cochlea, includes an elongate electrode array and a positioner. The electrode array has a multiplicity of electrode contacts carried on a flexible elongate carrier, which carrier is adapted for insertion into one of the spiraling ducts, e.g., the scala tympani, of the cochlea. The positioner is an elongate, flexible member, having a longitudinal channel that passes therethrough. The positioner is adapted to reside in and fill the space in the cochlear channel behind the electrode array so as to position and maintain the electrode array against a modiolar wall of the cochlea. A distal tip of the positioner is detachably joined to the electrode array at one point near the distal tip of the electrode array. To insert the electrode system into the cochlea, a stylet wire is inserted into the channel of the positioner, and the positioner is then gently guided and pushed into the cochlea by extending the stylet wire.

Abstract: A method of positioning an electrode array within a human cochlea includes making a flexible positioner as a curved or hooked shape from a silicone polymer. The positioner is adapted to be inserted into the scala tympani duct of a human cochlea. The positioner may be inserted into the scala tympani duct before, concurrent with, or after, insertion of the electrode array. The flexible positioner fills space within the scala tympani duct so as to force the electrode array, also inserted into the scala tympani duct, against the modiolar wall of the cochlea, where the electrode contacts of the electrode array may be more effective. In one embodiment, a channeling groove is formed along one side of the positioner for receiving the electrode array. Also, in one embodiment, a silastic tube forms a molded-in tube within the molded positioner, and provides a lumen, sealed or closed at its distal end, into which a stylet wire may be inserted during the insertion process.

Abstract: An insertion tool is used to insert an electrode array or positioner into a human cochlea. The insertion tool includes a main body portion (151), a pushing tube (152) slidably engaged within the main body portion so that the pushing tube may assume a retracted or extended position, and a stylet (154) slidably inserted into the pushing tube and having a retracted position and an extended position. In use, a positioner (or other flexible member), having a longitudinal hole or channel passing therethrough, is threaded onto the distal end of the stylet at a time when the stylet is in its extended position and the pushing tube is in its retracted position. Then, the pushing tube is pushed or slid to its extended position while maintaining the stylet in its extended position, thereby pushing the positioner (or other flexible member) off of the stylet and into the cochlea.

Abstract: A method of making an implantable electrode array, adapted for insertion into a cochlea, provides stability relative to the electrode contact direction. In-line electrodes are spaced-apart along one side of a flexible carrier. The structure of the electrode array facilitates bending of the array with the electrode contacts on the inside of the bend, yet deters flexing or twisting of the array in other directions. The electrode contacts preferably are each made from two strips of metal, arranged in a "T" shape (top view). During assembly, all of the "T" strips are held in position on an iron sheet. Two wire bundles are formed that pass along each side of each "T". The leg of each "T" is folded over to pinch at least one of the wires from one of the wire bundles therebetween. This pinched wire is then resistance welded to the strip. The sides of the "T" are then folded up and touch or nearly touch to form a ".DELTA." shape (side view). The wire bundles going to more distal electrodes pass through the ".DELTA.

Abstract: An implantable electrode array, adapted for insertion into a cochlea, provides improved stability of electrode contact direction. In-line electrodes are spaced-apart along one side of a flexible carrier. The structure of the electrode array facilitates bending of the array with the electrode contacts on the inside of the bend, yet deters flexing or twisting of the array in other directions. The electrode contacts preferably are each made from two strips of metal, arranged in a "T" shape (top view). During assembly, all of the "T" strips are held in position on an iron sheet. Two wire bundles are formed that pass along each side of each "T". The leg of each "T" is folded over to pinch at least one of the wires from one of the wire bundles therebetween. This pinched wire is then resistance welded to the strip. The sides of the "T" are then folded up and touch or nearly touch to form a ".DELTA." shape (side view). The wire bundles going to more distal electrodes pass through the ".DELTA.

Abstract: An electrode array has an elongate flexible carrier that, when viewed in cross-section, is much more flexible in a first direction than in a second direction orthogonal thereto. The elongate flexible carrier is formed with a bias force that causes the array to flex in the first direction so as to assume the general spiral or circular shape of the scala tympani duct within the cochlea. The less-flexible direction is the direction that makes it difficult for the array to twist as it is inserted within the scala tympani duct. The bias force is sufficiently strong to cause the array to assume its preformed spiral shape even after being straightened during initial insertion into the cochlea. Electrode contacts, embedded into the carrier so as to be exposed along an inner or concave surface of the spiral, thus wrap snugly around the modiolus, thereby positioning the electrode contacts against the modiolar wall in an optimum position for stimulation.

Abstract: An implantable electrode array, adapted for insertion into either a left or right cochlea, assumes a spiral shape so as to hug the modiolar wall of the cochlea after insertion into the cochlea. All of the electrode contacts are spaced apart along one edge or side of the array, termed the "medial side", which medial side resides on the inside of the spiral. The electrode contacts are thus positioned in close proximity to the modiolar wall, closest to the ganglion cells that are to be stimulated by the electrode array. A positioning stylet made from a suitable memory wire is inserted into a longitudinal channel of the array. The stylet is made from memory wire and has properties selected to return to a desired memory spiral shape at or near body temperature (e.g., approximately 37.degree. C. or 98.6.degree. F.). The positioning stylet is cooled and bent as needed to assume a relatively straight, or non-spiral shape.

Abstract: A microsurgical tool (8), in the form of forceps, allows access and micro-manipulation into very small confined spaces, such as the cochlea. The microsurgical tool includes an activation body (10) and a working head (20). The activation body is made from a pair of leaf springs (11) joined permanently at one end to a sliding bracket (12) and joined at the other end to a central section (15) with removable screws (13). The central section (15) tapers to an extension (15A) that extends to the working head. A push arm (16) has a first end coupled to the sliding bracket (12) and a second end pivotally joined to the working head (20). The working head (20) is made from a first jaw part (21) attached to the extension (15A), and a second jaw part (22) pivotally connected to the second end of the push arm (16).

Abstract: A tapered, flexible positioner, typically molded in a curved or hooked shape from a silicone polymer, is adapted to be inserted into the scala tympani duct of a human cochlea so as to position or force an electrode array, also inserted into the scala tympani duct, against the modiolar wall of the cochlea. The positioner may be inserted into the scala tympani duct before, or preferably after, insertion of the electrode array. The flexible positioner thus fills space within the scala tympani duct so as to force the electrode array, also inserted into the scala tympani duct, against the modiolar wall of the cochlea, where the electrode contacts of the electrode array may be more effective. In a preferred embodiment, a channeling groove is formed along one side of the positioner for receiving the electrode array.

Abstract: An electrode array has a flexible carrier that, when viewed in cross-section, is much more flexible in a first direction than in a second direction orthogonal thereto. The flexible direction is the direction that allows the array to readily flex so as to assume the general spiral or circular shape of the scala tympani duct within the cochlea. The less-flexible direction is the direction that makes it difficult for the array to twist as it is inserted within the scala tympani duct. By placing the electrode contacts of the array on or near that surface of the array which becomes the inner surface of the spiral shape once implantation has occurred, the electrode array may be inserted within the cochlea using minimal force, yet twisting of the array becomes unlikely during insertion or thereafter. Four separate embodiments of the electrode array are described.