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: The present invention provides a tip member for inserting into the cochlea, a device comprising: an elongate member including at least one electrode mounted thereon; and a tip member extending distally from a distal end of the elongate member, the tip member comprising a tapered portion tapering distally and a blunt end portion at a distal end of the tapered portion, wherein the tip member is resiliently flexible, and a method for making such a device.

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: An implantable tissue-stimulating prosthesis such as a cochlear implant system comprising an elongate carrier member having a distal end, a proximal end, and at least one electrode positioned thereon; at least one electrical conductor extending from one or more of the at least one electrode; a lead extending from the carrier member and enclosing the at least one electrical conductor; and a holding member constructed and arranged to radially extend outwardly from the surface of the carrier member to facilitate grasping of the holding member during implantation of the carrier member in a patient.

Abstract: A cochlear stimulation lead and method of making an aggressively curved electrode array are provided. In one embodiment of the lead, while the curved section of the lead is curled further beyond the originally molded curvature and held in this position, a filling channel is filled up with a filling material that is hardened or cured in this held position. The resulting lead has a tip curvature that is more curved than the originally molded curvature.

Abstract: In a cochlear implant system, the implantable stimulator includes a monitor which monitors parameters associated with the stimulation signals and/or the power stored in an energy storage element which stores energy transmitted from the processor. This parameter or parameters is/are analyzed and one or more feedback signals are generated and transmitted back to the processor. The processor uses the feedback signal to insure that power is transmitted to the stimulator optimally and that the stimulation signals are compliant.

Abstract: Novel non-invasive tactile hearing apparatus and methodology are disclosed which apparatus comprises tactile transmitter contiguously in contact with the skin of the user and, utilizing nerves as opposed to ears, enhances the hearing of those who are hearing-impaired and provides hearing to those who are legally deaf.

Abstract: A binaural cochlear implant system, including two intracochlear implants adapted for implantation in the cochleas of a user, each cochlear implant utilising a speech processing strategy wherein the electrical stimuli are matched to the relative timing of the relevant audio signals as detected at each ear, such that the interaural time delays between the audio signals at each ear are substantially preserved in electrical stimuli at each ear.

Abstract: An implantable cochlear implant electrode array (30) that can adopt a first, preferably straight, configuration selected to allow the array to be inserted into the cochlea and at least a second, preferably, spirally curved, configuration wherein the electrode array (30) is adapted to apply tissue stimulation. The electrode array (30) comprises an elongate carrier (31) having a proximal end (37), a distal end (34), and a plurality of electrodes supported by the carrier (31) at respective spaced locations thereon, the carrier (31) is formed, preferably moulded, to preferentially adopt the second configuration or another configuration different to said first configuration. The outer layer (33) is releasably connected to the elongate carrier (31) by an adhesive layer (32) and is formed so as to bias the carrier (31) into the first configuration when connected thereto. A method of forming the electrode array (30) is also disclosed.

Abstract: A laminated multi-electrode biocompatible implant, comprising a first layer of flexible, biocompatible dielectric material having a first, exposed surface. A second layer of flexible biocompatible dielectric material, is adhered to the first layer. Further, a third layer of flexible biocompatible dielectric material is adhered to the second layer. Additionally, a first conductive trace is interposed between the first layer and the second layer and a second conductive trace interposed between said second layer and said third layer. Finally, a first conductor, which breaches said first layer, conductively connects the first conductive trace to the exposed surface of the first layer, thereby forming a first electrode and a second conductor, which breaches the first layer and the second layer, conductively connects the second conductive trace to the exposed surface of the first layer, thereby forming a second electrode.

Abstract: A cochlear stimulation lead having a pre-curved electrode array is provided. The molding process provides memory to the curved part of the lead. The lead may be made having a stylet insertion channel that extends from a slightly curved or substantially straight section and into the highly curved section of the lead. Because high compliance is desired for the lead in cochlear stimulation applications, the compliance is controlled not only by the taper at the distal end of the lead and overall lead thickness, but also by choosing the material hardness of the lead carrier/covering and employing compliant zigzagged conductor wire. In addition, differential lead compliance/stiffness can be achieved by using a stiff tubing that forms part of the stylet insertion channel.

Abstract: A cochlear implant electrode assembly (10) comprising an elongate electrode carrier member (11), a bioresorbable stiffening element (15) and an outer layer (16) surrounding the stiffening element (15). The carrier member (11) is made of a resiliently flexible first material and has a plurality of electrodes (12) mounted thereon and has a first configuration selected to allow it to be inserted into an implantee's cochlea, and at least a second configuration wherein it is curved to match a surface of the cochlea. The bioresorbable stiffening element (15) has a configuration selected for biassing the elongate member (11) into the first configuratin and is made of a second material relatively stiffer than the first material and which dissolves or softens on exposure to cochlear fluids to permit the elongate member (11) to at least approach or adopt the second configuration.

Abstract: An implantable electrode array (30) that can adopt a first, preferably straight, configuration selected to allow the array to be inserted into an implantee's body, such as the cochlea, and at least a second, preferably spirally curved, configuration where the electrode array is adapted to apply tissue stimulation to the cochlea. The array (30) includes an elongate carrier (31) having a proximal end and a distal end and a plurality of electrodes (36) supported by the carrier (31) at respective longitudinally spaced locations thereon. The array (30) further comprises an outer layer (33) adhered to the elongate carrier (31) by an intermediate bioresorbable adhesive layer (32) positioned at least partially between the carrier (31) and the outer layer (33).

Abstract: A cochlear implant system comprising a first unit (5) adapted to be worn on or in one ear of an implantee. The first unit has a case housing componentry including a microphone (27), and a speech processor means (29). A second unit or accessory (30) is adapted to be worn on or in the other ear of the implantee. The second unit or accessory (30) has a case (31) housing a second power source. An electrical conduction means (58) for transmitting power from the second power source to the componentry of the first unit extends between the first and second units. Such a conduction means (58) can extend around the back of the head of the implantee.

Abstract: A middle ear prosthesis comprises a piston adapted to extend through an oval window when implanted in a human ear. A pair of jaws engage an ossicle when implanted in a human ear. A spring is coupled to the jaws for biasing the jaws toward one another to provide clamping pressure. The jaws are in turn connected to the piston.

Abstract: A quick-connect system for mechanically and electrically connecting two components therebetween. In an exemplary embodiment, the mechanical quick-connect is comprised of: a receptacle in the first component; a barrel protruding from the second component; and a lock for locking the barrel inside the receptacle. Electrical connection, such as a coaxial connection, can also be obtained between the barrel and receptacle, while in the locked position by using a pin assembly axially located in the barrel. The lock may comprise a tooth and slot configuration, wherein the tooth is in compressive contact with a spring which compression continuously exerts force on the tooth and causes the end of the tooth to engage to the cam slot on the barrel, thereby locking the barrel inside the receptacle. The barrel may be disengaged with a turn that is less than 180 degrees.

Abstract: An implantable electrode array (30) that can adopt a first configuration selected to allow the array (30) to be inserted into a cochlea (12) of an implantee and at least a second configuration in which the array can apply tissue stimulation. The array (30) comprises an elongate carrier (31) having a proximal end (37), a distal end (34), and an inner surface (35) conformable with the inner wall of the implantee's cochlea (12). A plurality of electrodes (36) are supported within the carrier (31) at respective spaced locations thereon in a region between the proximal end (37) and the distal end (34) with at least one of the electrodes having a surface that is at least adjacent the inner surface (35) of the carrier (31). The carrier (31) is formed in the second configuration from a first layer (32) and at least a second layer (32) of resiliently flexible material. A method of forming an array (30) is also described.

Abstract: A bio-implant having a length and a proximal and a distal end. The bio-implant has at least two lamina of dielectric material joined together, thereby defining a boundary and also defining a side surface that is intersected by this boundary. In addition, at least one set of conductors is interposed between the two lamina and extend lengthwise from the proximal end toward the distal end, each one of the set of conductors being terminated adjacent to the side surface to form a set of conductor terminations. Further, a set of electrode contact points are constructed on the side surface, with each electrode contact point contacting one of said conductor terminations.

Abstract: A threaded grommet, having an axial passageway therethrough, and made from a biocompatible material, such as titanium, is screwed into a cochleostomy made in the bony tissue adjacent the round window in order to provide a minimally-invasive access port into the cochlea. The threads included on the outside of the grommet engage the bony tissue and form a tight seal that holds the grommet securely in position. Such tight seal prevents cochlear fluids from escaping from inside of the cochlea. The axial passageway through the center of the grommet provides an opening, i.e., mechanical access, into the base end (the end of the cochlea nearest the round window) of the cochlea. Drugs, steroids, tissue-growth-inhibiting fluids, and the like, may be controllably delivered through the access hole into the cochlea, which access hole may be plugged when not needed. Additionally, an electrode array, e.g., a relatively short electrode array may, be inserted into the cochlea through the access hole.

Abstract: A cochlear implant electrode assembly device (10) comprising an elongate electrode carrier member (11), and a shape element (15) formed of a memory material, such as Nitinol. The elongate member (11) is made of a resiliently flexible first material and has a length and a plurality of electrodes (12) mounted thereon adapted to apply a preselected tissue stimulation. The elongate member (11) has a pre-formed curved orientation that at least substantially matches an inside surface of a cochlea, an implantable orientation different to said pre-formed orientation that allows said member to be inserted into an implantee's cochlea, and an at least one intermediate orientation between said implantable orientation and said pre-formed orientation. The shape element (15) is removably positioned within the elongate member (11) and extends along at least a portion of the length thereof.

Abstract: A cochlear implant system has a signal processor that fits in the ear canal of a user. The signal processor processes an acoustic signal present in the ear of the user to produce a representative radio signal. A power transmitter transmits an electrical power signal through the skin of the user. A cochlear implant receives the radio signal and the electrical power signal and produces for the auditory nerve of the user an electrical stimulation signal representative of the acoustic signal.

Abstract: A cochlear electrode array is adapted for use with a hybrid hearing aid system. The cochlear electrode array has a carrier on which spaced-apart electrode contacts are carried, and in one embodiment is formed in the shape of a blade, being flat in one direction and thin in another direction. In another embodiment, side fins extend out from opposing sides of the carrier on which the electrode contacts are carried. The blade electrode array, or electrode array with side fins, is adapted for minimally-invasive insertion into the inner ear. More particularly, the blade or finned electrode is designed to be inserted through a soft cochleostomy so as to reside between the spiral ligament membrane and the cochlear bony tissue along a lateral side of the cochlea, near the basal end of the cochlea.

Abstract: A spiral shield for an implantable secondary coil confines the electrical field of the coil, and thus prevents capacitive coupling of the coil through surrounding dielectrics (such as human tissue.) Known implantable devices receive power inductively, through a secondary coil, from a primary coil in an external device. Efficient power reception requires that the coils be tuned to the same resonant frequency. Use of the spiral shield results in predictable electrical behavior of the secondary coil and permits the secondary coil to be accurately tuned to the same resonate frequency as the primary coil. To further improve performance, spacers made from SILBIONE®LSR 70 reside between turns of the coil to reduce turn to turn and turn to shield capacitances. Reducing the capacitances prevents excessive reduction of the self resonant frequency of the coil. The coil is imbedded in SILBIONE®LSR 70, allowing for a thin and flexible coil.

Abstract: A cochlear implant electrode assembly device (10) comprising an elongate electrode carrier member (11), a first stiffening element (15a), and a second stiffening element (15b). The carrier member (11) is made of a resiliently flexible first material and has a plurality of electrodes (12) mounted thereon. The carrier member (11) has a first configuration selected to allow it to be inserted into an implantee's cochlea (30), a second configuration wherein it is curved in shape to match a surface of the cochlea (30), and at least one intermediate configuration between the first and second configurations. Both the first and second stiffening elements (15a, 15b) are made of a material relatively stiffer than said the material and in combination bias the elongate member into the first configuration. If either the first stiffening element (15a) or the second stiffening element (15b) are removed, the elongate member (11) adopts the at least one intermediate configuration.

Abstract: A laminated multi-electrode biocompatible implant, comprising a first layer of flexible, biocompatible dielectric material having a first, exposed surface. A second layer of flexible biocompatible dielectric material, is adhered to the first layer. Further, a third layer of flexible biocompatible dielectric material is adhered to the second layer. Additionally, a first conductive trace is interposed between the first layer and the second layer and a second conductive trace interposed between said second layer and said third layer. Finally, a first conductor, which breaches said first layer, conductively connects the first conductive trace to the exposed surface of the first layer, thereby forming a first electrode and a second conductor, which breaches the first layer and the second layer, conductively connects the second conductive trace to the exposed surface of the first layer, thereby forming a second electrode.

Abstract: An implantable electrode assembly includes a leading section attached to the distal end of an electrode array. The electrode array has electrodes spaced along its length. Cochleostomies are drilled at both the base and apex of the cochlea. The leading section is inserted through the basal cochleostomy and promoted to the apical cochleostomy. A forward end of the leading section is then pulled through the apical cochleostomy, which causes the electrode array to be pulled into the cochlea. A depth marker on the electrode array indicates complete insertion. The leading section is detached from the electrode array and the electrode array is placed in tension by gently pulling both ends, which tension causes the electrode array to hug the modiolar wall of the cochlea. Wedges may be inserted at both cochleostomies to maintain the electrode array in tension.

Abstract: An electrode system is provided for insertion into an ossified cochlea. The electrode system includes a first electrode array and a second electrode array, both of which are electrically connected to a suitable implantable cochlear stimulator (ICS). Each of the two electrode arrays has a plurality of spaced-apart electrode contacts along one side or surface thereof, e.g., eight to twelve electrode contacts on the first electrode array, and six to ten electrode contacts on the second electrode array. A tunnel is drilled through the ossified portion of the cochlea into which the first electrode array is snugly inserted. The second electrode array is inserted into the cochlea near the second turn thereof. Where the cochlea is fully ossified, a second tunnel is drilled through the ossified portion at the second turn. A positioner may be used with the second electrode array in order to position its electrode contacts against the modiolar wall of the cochlea.

Abstract: The present invention relates to a device for picking up biological electrical signals, and more precisely auditory evoked potentials generated by acoustic and/or electrical and/or mechanical stimulation of the cochlear, or of a portion of the auditory system in man or animal. The implantable device for measuring or picking up auditory evoked potentials comprises at least two extracochlear pickup electrodes connected to the inputs of a differential amplifier.

Abstract: An electrode array for a cochlear implant is formed with a carrier made, for example from silicone, is preshaped and is formed with a lumen. The array is shaped to assume a first. The array can be straightened, and held in a straight configuration by inserting a stylet into the lumen. The array relaxes to a shape matching the curvature of the cochlea when the lumen is removed. The electrodes of the array are disposed on one side of the array to face the modiolus when the array is inserted into the cochlea.

Abstract: An auditive prosthesis comprising an elongated carrier (31) which can be implanted in the scala tympani of a cochlea, which carrier is provided, over at least a part of its length, at a first side face with electrode elements and, at a second side face (32b) facing away from the first side face (32a), with an electric conductor. Said side faces are interconnected by a third side face (32c) and a fourth side face (32d), said first side face extending, in a state where the carrier is implanted in the scala tympani, opposite the basilar membrane of the cochlea. In order to achieve, after implantation, an information transfer to the auditory nerve which is as complete as possible, the third side face and the fourth side face of the carrier are arranged, over at least a part of the length of the carrier where electrode elements are present, at distances from each other which are at least substantially equal to corresponding dimensions of the scala tympani which are parallel to the basilar membrane.

Abstract: An electrode system includes (1) an electrode array, made in a straight or curved shape, but made on a flexible carrier so that it can easily bend within a curved body cavity, such as the cochlea; and (2) a flexible positioner, molded in a curved or straight shape from a silicone polymer so as to make it easy to slide into the body cavity. Some embodiments may further include an electrode and/or a positioner guiding insert. One embodiment of the positioner includes keeper tabs at its distal end, and side walls at its proximal end, to help maintain the positioner in a desired position along the back side of the electrode array during and after the insertion process.

Abstract: Partially or fully implantable hearing aid for rehabilitation of an inner ear hearing disorder, with a microphone (10) which delivers an audio signal, an electronic signal processing and amplification unit (40, 50, 80, 140, 141) which is located in an audio signal-processing electronic hearing aid path, an implantable electromechanical output converter (20) and a unit (60) for power supply of the implant. The hearing aid is provided with an electronic module (90, 140, 141) for rehabilitation of tinnitus and it generates the signals necessary for a tinnitus masking or noiser function and feeds them into the audio signal processing path of the hearing implant.

Abstract: A method and apparatus for treating tinnitus involves generating a noise signal to mask the ringing or buzzing in the ears caused by tinnitus and transposing the noise signal into the ultrasonic frequency range. As such, the masking signal effectively masks the tinnitus noise without interfering with the subject's perception of normal sounds such as human speech. In an alternative embodiment, human speech is transduced into electrical signals, transposed to the ultrasonic frequency range, and physically applied to the patient while tinnitus masking signals in the auditory range are applied to the patient.

Abstract: A multi-bipolar configured electrode array and means to uniquely position said array within the scalae of the human cochlea is described. Said array is inserted into the scala tympani, scala vestibuli or both, by a surgeon. The electrode array may be pre-formed to lightly hug the modiolar wall of a scala so as to position the electrodes in close proximity to the cochlear spiral lamina and spiral ganglia in the modiolus. Mechanical features within said array allow the surgeon to further position said array against the modiolar wall of the scala, post insertion, and to mechanically retain such positioning of said array. Such positioning is in close proximity to surviving neural sites in the spiral lamina and/or spiral ganglion cells in the modiolus to efficiently stimulate functioning auditory neural elements. The multi-bipolar electrode configuration achieves a high degree of spatial selectivity, thus improving the implantee's speech percepts.

Abstract: An electrode array for a cochlear implant is formed with a carrier made, for example from silicone, is preshaped and is formed with a lumen. The array is shaped to assume a first. The array can be straightened, and held in a straight configuration by inserting a stylet into the lumen. The array relaxes to a shape matching the curvature of the cochlea when the lumen is removed. The electrodes of the array are disposed on one side of the array to face the modiolus when the array is inserted into the cochlea.

Abstract: A totally implantable cochlear prosthesis is presented. An externally-activated subcutaneous switch controls functions of the prosthesis. A pliable bridge connecting two hermetically sealed housing sections, and corrugated conductor lines, provide for future dimensional changes due to head growth. An encapsulated microphone is positioned underneath the skin in the posterior wall of the external auditory canal. A modiolus-hugging electrode array is inserted into one of the cochlea scala. Periodic charging of the implanted battery is accomplished via an external mechanically held head-mounted device containing an external coil, said external coil inductively coupling electrical power to an implanted receiving coil. The external and implanted coils can also be used as a communication link to program the implanted electronics.

Abstract: An electrode system adapted for insertion into a human cochlea as part of a cochlear stimulation system includes (1) an electrode array, made in a straight or curved shape, but made on a flexible carrier so that it can easily bend within a curved body cavity, such as the cochlea; and (2) a flexible positioner, molded in a curved or straight shape from a silicone polymer so as to make it easy to slide into the body cavity. A distal tip of the positioner is attached to the electrode array at a location that is proximal from the distal end of the electrode array about 3-5 mm. An insertion tube facilitates insertion of the electrode system into a human cochlea in one operation with the aid of a movable stylet wire. One embodiment of the positioner includes keeper tabs at its distal end, and side walls at its proximal end, to help maintain the positioner in a desired position along the back side of the electrode array during and after the insertion process.

Abstract: An implantable connector electrically connects a multi-conductor lead (22) with a small-dimensioned implantable housing (102) of an implantable medical device, such as a cochlear stimulator. The implantable housing has electronic circuitry hermetically sealed therein. The implantable connector includes a header (10) formed along an edge of the implantable housing. The header has a cavity (11) formed therein with a first array of electrical contacts (12) embedded within a bottom surface of the cavity. The electrical contacts are electrically connected with the electronic circuitry through hermetic feedthrough terminals. The header further has a niche (15) and a channel (14) formed therein. A connector pad (20) is dimensioned to fit snugly within the cavity. A bottom surface of the connector pad has a second array of electrical contacts (21) formed therein. The second array of electrical contacts aligns with the first array of electrical contacts in the cavity when the pad is placed inside of the cavity.

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 new surgical method and tools are described for the implantation of electrode arrays into the canalis cochlearis of profoundly deaf persons. Access to the canalis cochlearis is via the bony exterior ear canal and the middle ear, rather than the conventional route of drilling a cleft through the mastoid region posterior to the ear. Preferably entry to the canalis cochlearis is at a tangential angle to the curve of the basal turn. A template is described for landmarking the site for tangentially drilling into the canalis cochlearis comprising a plate shaped to be positioned by reference to the round window of the middle ear and the oval window. A device for holding open the field of view for the surgeon during implantation comprises elongated funnels.

Abstract: A tool for inserting medical electrodes such as nerve-stimulating electrodes into tissue. An electrode is positioned fully within a tip of the tool so the tip end can be placed directly against the tissue to be penetrated for precise handheld positioning. A trigger on the tool is actuated to release a compressed spring in the tool to drive the electrode out of the tool tip into the target tissue. A viscous-damping means is provided in the tool to control electrode acceleration and velocity.

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: 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: 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: An electrode array, made in a straight or curved shape, but made on a flexible carrier so that it can easily bend within a curved body cavity, such as the cochlea. The electrode array having a multiplicity of electrode contacts along a front side of the electrode array and a plurality of flexible ribs located on an opposite rear side. Insertion of the electrode array is performed by inserting the electrode array into the scala tympani (one of the channels of the cochlea) to a desired depth, which desired depth typically involves a rotation of about 360 degrees and causes the flexible ribs to make contact against the outer or lateral wall of the scala tympani, positioning the electrode contacts adjacent the inner wall of the scala tympani.

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.