Implantable assembly with reinforcement element

Abstract

An apparatus includes an assembly configured to be implanted on or within a recipient. The assembly includes an elongate body having a longitudinal axis and a flexible material, at least one element facing outwardly from the body and configured to be in operative communication with a portion of the recipient, at least one signal conduit in operative connection with the at least one element, the at least one signal conduit enclosed by the flexible material and extending along a length in a direction substantially parallel to the longitudinal axis. The assembly further includes at least one reinforcement element enclosed by the flexible material and extending along the length in the direction substantially parallel to the longitudinal axis. The at least one reinforcement element has a plurality of recesses distributed along the length and that contain the flexible material.

Description

IMPLANTABLE ASSEMBLY WITH REINFORCEMENT ELEMENTBACKGROUNDField

[0001] The present application relates generally to implantable medical devices comprising stimulation or measurement assemblies and systems and methods for implanting the stimulation or measurement assemblies.Description of the Related Art

[0002] Medical devices have provided a wide range of therapeutic benefits to recipients over recent decades. Medical devices can include internal or implantable components / de vices, external or wearable components / devices, or combinations thereof (e.g., a device having an external component communicating with an implantable component). Medical devices, such as traditional hearing aids, partially or fully-implantable hearing prostheses (e.g., bone conduction devices, mechanical stimulators, cochlear implants, etc.), pacemakers, defibrillators, functional electrical stimulation devices, and other medical devices, have been successful in performing lifesaving and / or lifestyle enhancement functions and / or recipient monitoring for a number of years.

[0003] The types of medical devices and the ranges of functions performed thereby have increased over the years. For example, many medical devices, sometimes referred to as “implantable medical devices,” now often include one or more instruments, apparatus, sensors, processors, controllers or other functional mechanical or electrical components that are permanently or temporarily implanted in a recipient. These functional devices are typically used to diagnose, prevent, monitor, treat, or manage a disease / injury or symptom thereof, or to investigate, replace or modify the anatomy or a physiological process. Many of these functional devices utilize power and / or data received from external devices that are part of, or operate in conjunction with, implantable components.SUMMARY

[0004] In one aspect disclosed herein, an apparatus comprises an assembly configured to be implanted on or within a recipient. The assembly comprises an elongate body having a longitudinal axis and comprising a flexible material. The assembly further comprises at least one element facing outwardly from the body. The at least one element is configuredto be in operative communication with a portion of the recipient. The assembly further comprises at least one signal conduit in operative connection with the at least one element. The at least one signal conduit is enclosed by the flexible material and extends along a length in a direction substantially parallel to the longitudinal axis. The assembly further comprises at least one reinforcement element enclosed by the flexible material and extending along the length in the direction substantially parallel to the longitudinal axis. The at least one reinforcement element comprises a plurality of recesses distributed along the length and that contain the flexible material.

[0005] In another aspect disclosed herein, a method comprises accessing a plurality of electrical wires extending along a longitudinal axis and having end portions that are spaced from one another along the longitudinal axis. The method further comprises positioning a bendable reinforcing element adjacent to the plurality of electrical wires. The reinforcing element extends along the longitudinal axis and has a higher tensile strength than does the plurality of electrical wires. The method further comprises encasing the plurality of electrical wires and the reinforcing element in a resilient material to form a bendable assembly. The resilient material extends into orifices and / or indentations of the reinforcing element.

[0006] In another aspect disclosed herein, a method comprises accessing an apparatus comprising a flexible assembly comprising a plurality of electrodes, a plurality of wires affixed to the plurality of electrodes, and a strip with a plurality of orifices extending at least partially therethrough. The wires and the strip are encased within a flexible material with the wires and the strip extending substantially parallel to one another, and the flexible material within the plurality of orifices. The method further comprises inserting the flexible assembly at least partially into a region of the recipient’s body. The method further comprises , during said inserting, using the strip to inhibit damage caused by tensile forces applied to the flexible assembly to the wires and / or to connections of the wires to the electrodes.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Implementations are described herein in conjunction with the accompanying drawings, in which:

[0008] FIG. 1 is a perspective view of an example auditory prosthesis implanted in a recipient with a stimulation assembly inserted into the cochlea in accordance with certain implementations described herein;

[0009] FIG. 2 schematically illustrates a simplified side view of an example internal component of an auditory prosthesis in accordance with certain implementations described herein;

[0010] FIG. 3 is cross-sectional view of the cochlea illustrating a stimulating assembly partially implanted therein in accordance with certain implementations described herein;

[0011] FIGs. 4A-4F schematically illustrate various configurations during an example implantation of a perimodiolar stimulation assembly into the cochlea of the recipient in accordance with certain implementations described herein;

[0012] FIGs. 5A-5D schematically illustrate portions of various example apparatus comprising an assembly in accordance with certain implementations described herein;

[0013] FIGs. 6A-6E schematically illustrate top views of various example reinforcement elements in accordance with certain implementations described herein;

[0014] FIG. 7 is a flow diagram of an example method in accordance with certain implementations described herein; and

[0015] FIG. 8 is a flow diagram of another example method in accordance with certain implementations described herein.DETAILED DESCRIPTION

[0016] Certain implementations described herein provide an assembly (e.g., stimulation assembly) implantable into a recipient’s body and having one or more signal conduits (e.g., wires; optical fibers) and one or more body-interfacing elements (e.g., electrodes; optical emitters or contacts) configured to be in operational communication with respective portions (e.g., tissue; bodily fluid) of the recipient’s body. The assembly includes an elongate reinforcement element configured to protect the signal conduits and / or connections between the signal conduits and the body-interfacing elements against damage (e.g., breakage) due to tensile forces applied to the assembly (e.g., from stretching of the assembly), while not substantially adversely affecting performance (e.g., bending stiffness; flexibility; insertion force applied during implantation; shape retention) or robustness (e.g., resilience against delamination) of the assembly. The reinforcement element can also be used to tailor (e.g., tune) the flexibility of various sections of the assembly to have consistent stiffnesses among multiple such assemblies. The reinforcement element can be incorporated into the assemblyduring fabrication (e.g., molding, either before or after connecting the signal conduits to the body-interfacing elements) of the assembly. The reinforcement element can reduce yield loss (e.g., open circuits; broken signal conduits) incurred during fabrication and / or handling of the assembly.

[0017] The teachings detailed herein are applicable, in at least some implementations, to any type of implantable stimulation or measurement system (e.g., implantable auditory prosthesis device or system; neurostimulation system; machine-brain interface system; muscle stimulation system). The system can comprise a first portion implanted on or within the recipient’s body and a second portion (e.g., implanted on or within the recipient or external to the recipient’s body). For example, the first portion can be configured to provide stimulation signals to a portion of the recipient’s body in response to received information and / or control signals from the second portion of the system. For another example, the first portion can be configured to generate sensor signals indicative of an attribute of the portion of the recipient’s body and to provide the sensor signals to the second portion. Implementations can include any type of medical device that can utilize the teachings detailed herein and / or variations thereof. Furthermore, while certain implementations are described herein in the context of auditory prosthesis devices, certain other implementations are compatible in the context of other types of devices or systems that provide a wide range of therapeutic benefits to recipients, patients, or other users.

[0018] Merely for ease of description, apparatus and methods disclosed herein are primarily described with reference to an illustrative medical device, namely an implantable transducer assembly including but not limited to: electro-acoustic electrical / acoustic systems, cochlear implant devices, implantable hearing aid devices, middle ear implant devices, bone conduction devices (e.g., active bone conduction devices; passive bone conduction devices, percutaneous bone conduction devices; transcutaneous bone conduction devices), Direct Acoustic Cochlear Implant (DACI), middle ear transducer (MET), electro-acoustic implant devices, other types of auditory prosthesis devices, and / or combinations or variations thereof, or any other suitable hearing prosthesis system with or without one or more external components. Certain such implementations can be referred to as “partially implantable,” “semi-implantable,” “mostly implantable,” “fully implantable,” or “totally implantable”auditory prostheses. In some implementations, the teachings detailed herein and / or variations thereof can be utilized in other types of prostheses beyond auditory prostheses.

[0019] In some implementations, the teachings detailed herein and / or variations thereof can be utilized in other types of implantable medical devices beyond auditory prostheses. For example, apparatus and methods disclosed herein and / or variations thereof can also be used with other types of sensory prosthesis systems or devices (e.g., configured to evoke other types of neural or sensory percepts such as sight, tactile, smell, taste) or with other types of medical devices that can utilize the teachings detailed herein and / or variations thereof to provide a wide range of therapeutic benefits to recipients, patients, or other users, such as one or more of the following: vestibular devices (e.g., vestibular implants); tinnitus treatment devices; visual devices (e.g., bionic eyes); visual prostheses (e.g., retinal implants); cardiac pacemakers; drug delivery systems; defibrillators; functional electrical stimulation devices; catheters; neurostimulators; brain implants; somatosensory implants; chemosensory implants; seizure devices (e.g., devices for monitoring and / or treating epileptic events); sleep apnea devices; electroporation devices; pain relief devices; bladder control devices; swallowing treatment devices (e.g., devices for treating difficulties with the hyoglossus and / or thyrohyoid muscles); dysphagia treatment devices; devices for treating dry mouth (e.g., xerostomia or hyposalivation), devices for treating excessive or absence of muscle movement due to stroke, Parkinson’s disease, or other brain disorders, devices for treating hypertension (e.g., by stimulating the carotid sinus barosensory system); etc. Other example apparatus and methods disclosed herein and / or variations thereof can be used to perform monitoring or measuring functionalities (e.g., sensors; electroencephalogram monitoring of brain function; electrocardiogram monitoring of heart function).

[0020] FIG. 1 is a perspective view of an example auditory prosthesis 100 (e.g., cochlear implant), implanted in a recipient with a stimulation assembly 118 inserted into the cochlea 140 in accordance with certain implementations described herein. As shown in FIG. 1, the recipient has an outer ear 101, a middle ear 105, and an inner ear 107. In a fully functional ear, the outer ear 101 comprises an auricle 110 and an ear canal 102. An acoustic pressure or sound wave 103 is collected by the auricle 110 and is channeled into and through the ear canal 102. Disposed across the distal end of the ear canal 102 is a tympanic membrane 104 which vibrates in response to the sound wave 103. This vibration is coupled to ovalwindow or fenestra ovalis 112 through three bones of middle ear 105, collectively referred to as the ossicles 106 and comprising the malleus 108, the incus 109, and the stapes 111. The bones 108, 109, and 111 of the middle ear 105 serve to filter and amplify the sound wave 103, causing the oval window 112 to articulate, or vibrate in response to vibration of the tympanic membrane 104. This vibration sets up waves of fluid motion of the perilymph within the cochlea 140. Such fluid motion, in turn, activates tiny hair cells (not shown) inside the cochlea 140. Activation of the hair cells causes appropriate nerve impulses to be generated and transferred through the spiral ganglion cells (not shown) and auditory nerve 114 to the brain (also not shown) where they are perceived as sound.

[0021] As shown in FIG. 1, the example auditory prosthesis 100 comprises one or more components which are temporarily or permanently implanted in the recipient. The example auditory prosthesis 100 is shown in FIG. 1 with an external component 142 which is directly or indirectly attached to the recipient’s body, and an internal component 144 which is temporarily or permanently implanted in the recipient (e.g., positioned in a recess of the temporal bone adjacent to the auricle 110 of the recipient). The external component 142 typically comprises one or more sound input elements (e.g., an external microphone 124) for detecting sound, a sound processing unit 126 (e.g., disposed in a Behind-The-Ear unit), a power source (not shown), and an external transmitter unit 128. In the illustrative implementation of FIG. 1, the external transmitter unit 128 comprises an external coil 130 (e.g., a wire antenna coil comprising multiple turns of electrically insulated single-strand or multi-strand platinum or gold wire) and, preferably, a magnet (not shown) secured directly or indirectly to the external coil 130. The external coil 130 of the external transmitter unit 128 is part of an inductive radio frequency (RF) communication link with the internal component 144. The sound processing unit 126 processes the output of the microphone 124 that is positioned externally to the recipient’s body, in the depicted implementation, by the recipient’s auricle 110. The sound processing unit 126 generates encoded signals, sometimes referred to herein as encoded data signals, which are provided to the external transmitter unit 128 (e.g., via a cable).

[0022] The power source of the external component 142 is configured to provide power to the auditory prosthesis 100, where the auditory prosthesis 100 includes a battery (e.g., located in the internal component 144, or disposed in a separate implanted location) that isrecharged by the power provided from the external component 142 (e.g., via a transcutaneous energy transfer link). The transcutaneous energy transfer link is used to transfer power and / or data to the internal component 144 of the auditory prosthesis 100. Various types of energy transfer, such as infrared (IR), electromagnetic, capacitive, and inductive transfer, may be used to transfer the power and / or data from the external component 142 to the internal component 144. During operation of the auditory prosthesis 100, the power stored by the rechargeable battery is distributed to the various other implanted components as needed.

[0023] The internal component 144 comprises an internal receiver unit 132, a stimulator unit 120, and an elongate stimulation assembly 118. In some implementations, the internal receiver unit 132 and the stimulator unit 120 are hermetically sealed within a biocompatible housing, sometimes collectively referred to as a stimulator / receiver unit. The internal receiver unit 132 comprises an internal coil 136 (e.g., a wire antenna coil comprising multiple turns of electrically insulated single-strand or multi-strand platinum or gold wire), and preferably, a magnet (also not shown) fixed relative to the internal coil 136. The internal coil 136 receives power and / or data signals from the external coil 130 via a transcutaneous energy transfer link (e.g., an inductive RF link). The stimulator unit 120 generates electrical stimulation signals based on the data signals, and the stimulation signals are delivered to the recipient via the elongate stimulation assembly 118.

[0024] The elongate stimulation assembly 118 has a proximal end connected to the stimulator unit 120, and a distal end implanted in the cochlea 140. The stimulation assembly 118 extends from the stimulator unit 120 to the cochlea 140 through the mastoid bone 119. In some implementations, the stimulation assembly 118 may be implanted at least in the basal region 116, and sometimes further. For example, the stimulation assembly 118 may extend towards the apical end of the cochlea 140, referred to as the cochlea apex 134. In certain circumstances, the stimulation assembly 118 may be inserted into the cochlea 140 via a cochleostomy 122. In other circumstances, a cochleostomy 122 may be formed through the round window 121, the oval window 112, the promontory 123, or through an apical turn 147 of the cochlea 140.

[0025] The elongate stimulation assembly 118 comprises a longitudinally aligned and distally extending array 146 (e.g., electrode array; contact array) of stimulation elements 148 (e.g., electrical electrodes; electrical contacts; optical emitters; optical contacts). Forexample, the stimulation elements 148 can comprise intra-cochlear electrodes (ICEs) and / or extra-cochlear electrodes (ECEs). The stimulation elements 148 are longitudinally spaced from one another along a length of the elongate body of the stimulation assembly 118. For example, the stimulating assembly 118 can comprise an array 146 comprising twenty-two (22) stimulation elements 148 that are configured to deliver stimulation to the cochlea 140. Although the array 146 of stimulation elements 148 can be disposed on the stimulation assembly 118, in most practical applications, the array 146 is integrated into the stimulation assembly 118 (e.g., the stimulation elements 148 of the array 146 are disposed in the stimulation assembly 118). As noted, the stimulator unit 120 generates stimulation signals (e.g., electrical signals; optical signals) which are applied by the stimulation elements 148 to the cochlea 140, thereby stimulating the auditory nerve 114.

[0026] While FIG. 1 schematically illustrates an auditory prosthesis 100 utilizing an external component 142 comprising an external microphone 124, an external sound processing unit 126, and an external power source, in certain other implementations, one or more of the microphone 124, sound processing unit 126, and power source are implantable on or within the recipient (e.g., within the internal component 144). For example, the auditory prosthesis 100 can have each of the microphone 124, sound processing unit 126, and power source implantable on or within the recipient (e.g., encapsulated within a biocompatible assembly located subcutaneously), and can be referred to as a totally implantable cochlear implant (“TICI”). For another example, the auditory prosthesis 100 can have most components of the cochlear implant (e.g., excluding the microphone, which can be an in-the-ear-canal microphone) implantable on or within the recipient, and can be referred to as a mostly implantable cochlear implant (“MICI”).

[0027] A variety of types of intra-cochlear stimulation assemblies 118 are compatible with certain implementations described herein, including but not limited to: short, straight, and perimodiolar. A perimodiolar stimulation assembly 118 is configured to adopt a curved configuration during and / or after implantation into the cochlea 140. To achieve this, in certain implementations, the perimodiolar stimulation assembly 118 is pre-curved to the same general curvature of the cochlea 140. Such examples of the stimulation assembly 118 can be held straight by, for example, a stiffening stylet (not shown in FIG. 1) or sheath 260 which is removed during implantation, or alternatively varying material combinations or theuse of shape memory materials, so that the stimulation assembly 118 may adopt its curved configuration when in the cochlea 140. Other methods of implantation, as well as other stimulation assemblies 118 which adopt a curved configuration, may be used. The stimulation assembly 118 of certain other implementations comprises a non-perimodiolar stimulation assembly 118. For example, the stimulation assembly 118 can comprise a straight stimulation assembly 118 or a mid-scala assembly which assumes a mid-scala position during or following implantation. Alternatively, the stimulation assembly 118 can comprise a short electrode implanted into at least the basal region of the cochlea 140. The stimulation assembly 118 can extend towards the apical end of the cochlea 140, referred to as the cochlea apex. In certain implementations, the stimulation assembly 118 is configured to be inserted into the cochlea 140 via a cochleostomy (e.g., formed through the oval window 112, the round window 121, the promontory 123, or through an apical turn of the cochlea 140).

[0028] FIG. 2 schematically illustrates a simplified side view of an example internal component 144 comprising an internal receiver unit 132 which receives encoded signals from an external component 142 of the auditory prosthesis 100 (e.g., cochlear implant system). The internal component 144 terminates in the stimulation assembly 118 that comprises an extra-cochlear region 210 and an intra-cochlear region 212. The intra-cochlear region 212 is configured to be implanted in the recipient’s cochlea 140 and has disposed thereon the longitudinally aligned and distally extending array 146 (e.g., electrode array; contact array) comprising a plurality of stimulation elements 148. In the example schematically illustrated in FIG. 2, the plurality of stimulation elements 148 comprises electrical contacts (e.g., electrodes) configured to apply electrical stimulation and / or optical contacts (e.g., emitters) configured to apply optical stimulation, either alone or in conjunction with electrical or other stimulation mechanisms.

[0029] In certain implementations, the stimulation assembly 118 comprises a lead region 220 coupling the internal receiver unit 132 to the array 146. In certain implementations, optical and / or electrical stimulation signals generated by the internal receiver unit 132 are delivered to the array 146 via the lead region 220. The lead region 220 comprises a first portion 222 configured to accommodate movement (e.g., is flexible) and a second portion 224 configured to connect the first portion 222 to the array 146. The first portion 222 of certain implementations is configured to prevent the stimulation assembly 118, the lead region 220and its connection to the internal receiver unit 132, and the array 146 from being damaged due to movement of the internal component 144 (or part of the internal component 144) which may occur, for example, during mastication. In certain implementations, the second portion 224 comprises a distinct connection to the first portion 222 and / or the array 146, while in certain other implementations, the second portion 224 is blended into the first portion 222 and / or the array 146. The relative lengths of the stimulation assembly 118, the lead region 220, the first portion 222, the second portion 224, the extra-cochlear region 210, the intra-cochlear region 212, and the array 146 are not shown to scale in FIG. 2.

[0030] In certain implementations, the lead region 220 comprises a body 226 and a plurality of signal conduits (e.g., electrical wire leads; optical waveguides)(not shown) within the body 226. For example, the body 226 can comprise silicone or other biocompatible material in which the signal conduits are embedded (e.g., the body 226 is molded around the signal conduits) or the body 226 can comprise a tube in which the signal conduits are contained (e.g., the tube backfilled with silicone). The signal conduits of certain implementations comprise wires (e.g., platinum; platinum-iridium alloys) and / or one or more optical fibers or waveguides (e.g., silica-based glass or plastic) having outer diameters that are wavy or helixed around an axis substantially parallel to the longitudinal direction of the lead region 220 (e.g., within the first portion 222) and / or are substantially straight and substantially parallel to the longitudinal direction (e.g., within the second portion 224). In certain implementations, each of the signal conduits is operatively connected to a corresponding one of the plurality of stimulation elements 148 of the array 146.

[0031] In certain implementations, the extra-cochlear region 210 is located in the middle ear cavity of the recipient after implantation of the intra-cochlear region 212 into the cochlea 140. Thus, the extra-cochlear region 210 corresponds to a middle ear cavity subsection of the array 146. In certain implementations, an outer surface of the extra-cochlear region 210 comprises nubs 214 configured to aid in the manipulation of the stimulation assembly 118 during insertion of the intra-cochlear region 212 into the cochlea 140.

[0032] FIG. 3 is cross-sectional view of the cochlea 140 illustrating the stimulating assembly 118 partially implanted therein in accordance with certain implementations described herein. Only a subset of the stimulation elements 148 of the stimulation assembly 118 is shown in FIG. 3. The cochlea 140 is a conical spiral structure that comprises three parallel fluid- filledcanals or ducts, collectively and generally referred to herein as canals 236. Canals 236 comprise the tympanic canal 237, also referred to as the scala tympani 237, the vestibular canal 238, also referred to as the scala vestibuli 238, and the median canal 239, also referred to as the scala media 239. The cochlea 140 includes the modiolus 240 which is a conical shaped central region around which the cochlea canals 236 spiral. The modiolus 240 consists of spongy bone in which the cochlea nerve cells, sometimes referred to herein as the spiral ganglion cells, are situated. The cochlea canals 236 generally turn 2.5 times around the modiolus 240.

[0033] In normal hearing, sound entering the auricle 110 (see, e.g., FIG. 1) causes pressure changes in the cochlea 140 that travel through the fluid-filled tympanic and vestibular canals 237, 238. The organ of Corti 242, which is situated on the basilar membrane 244 in scala media 239, contains rows of hair cells (not shown) which protrude from its surface. Located above the hair cells is the tectoral membrane 245 which moves in response to pressure variations in the fluid-filled tympanic and vestibular canals 237, 238. Small relative movements of the layers of the tectoral membrane 245 are sufficient to cause the hair cells to move, thereby causing the creation of a voltage pulse or action potential which travels along the associated nerve fibers that connect the hair cells with the auditory nerve 114. The auditory nerve 114 relays the impulses to the auditory areas of the brain (not shown) for processing.

[0034] Typically, in cochlear implant recipients, some portion of the cochlea 140 (e.g., the hair cells) is damaged such that the cochlea 140 cannot transduce pressure changes into nerve impulses for relay to the brain. As such, the stimulating elements 148 of the stimulating assembly 118 are used to directly stimulate the cells to create nerve impulses resulting in perception of a received sound (e.g., to evoke a hearing percept).

[0035] FIGs. 4A-4F schematically illustrate various configurations during an example implantation of a perimodiolar stimulation assembly 118 into the cochlea 140 of the recipient in accordance with certain implementations described herein. The perimodiolar stimulation assembly 118 is substantially enclosed in a sheath 260 (e.g., cannula; insertion tube) of an insertion tool configured to protect the stimulation assembly 118 during the implantation process. The sheath 260 is further configured to provide sufficient rigidity to maintain the pre-curved perimodiolar stimulation assembly 118 in a substantially straight configuration during at least a portion of the implantation process. While FIGs. 4A-4Fschematically illustrate an example implantation of a perimodiolar stimulation assembly 118 into a cochlea 140 using a sheath 260, in certain other implementations, other types of assemblies (e.g., straight) can be inserted into other regions of the recipient’s body by other means (e.g., no sheath; using a stylet).

[0036] In certain implementations, the implantation process includes creating an opening (e.g., facial recess) through the recipient's mastoid bone 119 (see, e.g., FIG. 1) to access the recipient's middle ear cavity (see, e.g., FIG. 1). A cochleostomy 122 is created from the middle ear cavity into the cochlea 140 (e.g., through the round window 121, oval window 112, the promontory 123, etc. of the cochlea 140). The stimulation assembly 118 and the surrounding sheath 260 are advanced (e.g., pushed) through the opening through the mastoid bone 119 and are positioned to be inserted into the cochleostomy 122, as schematically illustrated in FIG. 4A.

[0037] As schematically illustrated in FIG. 4B, the stimulation assembly 118 and the sheath 260 are advanced (e.g., pushed) together through the cochleostomy 122 to insert a distal end portion 262 of the sheath 260 within the cochlea 140 while the stimulation assembly 118 remains in the sheath 260. The advancement of the stimulation assembly 118 and the surrounding sheath 260 is stopped once a proximal end portion 264 of the sheath 260 is in a predetermined position (e.g., in contact with the cochlea 140 at the cochleostomy 122). As schematically illustrated by FIG. 4C, the stimulation assembly 118 is then gently advanced (e.g., pushed) forward into the cochlea 140 through the sheath 260 such that an apical (e.g., distal end / tip) portion 228 of the array 146 exits the sheath 260 through an opening in the distal end portion 262 of the sheath 260. The portion of the stimulation assembly 118 that extends out of the sheath 260 is no longer constrained to be straight by the stimulation assembly 118 and therefore returns to its pre-curved configuration to follow the curvature of the canals 236 within the cochlea 140. As schematically illustrated by FIG. 4D, the advancement of the stimulation assembly 118 continues until the stimulation assembly 118 achieves the implanted position. For example, the implanted position can be the position at which the apical portion 228 of the array 146 is placed at a selected angular position (e.g., the apical portion 228 of the array 146 is at the cochlea apex 134). Once the stimulation assembly 118 achieves the implanted position, the sheath 260 can be withdrawn from the cochlea 140 (e.g., pulled out) through the cochleostomy 122, as schematically illustrated by FIGs. 4E-4F.

[0038] The effectiveness of the stimulation by the stimulation assembly 118 depends, at least in part, on the place along the basilar membrane 244 where the stimulation is delivered. That is, the cochlea 140 has characteristically been referred to as being "tonotopically mapped," in that regions of the cochlea 140 toward the basal end are more responsive to high frequency signals, while regions of cochlea 140 toward the cochlea apex 134 are more responsive to low frequency signals. These tonotopical properties of the cochlea 140 are exploited in a cochlear implant by delivering stimulation within a predetermined frequency range to a region of the cochlea 140 that is most sensitive to that particular frequency range. However, this stimulation relies on the particular stimulation elements 148 having a final implanted positioned adjacent to a corresponding tonotopic region of the cochlea 140 (e.g., a region of the cochlea 140 that is sensitive to the frequency of sound represented by the stimulation element 148).

[0039] To achieve a selected final implanted position, the apical portion 228 of the array 146 is placed at a selected angular position (e.g., angular insertion depth; angular rotation of the apical portion 228 of the array 146 from the cochleostomy 122 through which the stimulation assembly 118 enters the cochlea 140). In certain implementations, while the stimulation assembly 118 is being implanted (e.g., during a surgical procedure conducted by an operator, such as a medical professional, surgeon, and / or an automated or robotic surgical system), a location and / or an orientation of the array 146 relative to the cochlea 140 (e.g., collectively referred to as the pose of the array 146) is adjusted as the array 146 is advanced and placed into position within the cochlea 140. The goal of the implantation is that the fully- implanted array 146 has an optimal pose in which the array 146 is positioned such that the stimulation elements 148 are adjacent to the corresponding tonotopic regions of the cochlea 140. To achieve the optimal pose, the array 146 is expected to follow a trajectory in the cochlea 140 whereby (i) the stimulation elements 148 are distributed linearly along an axis of the scala media 239, (ii) the array 146 does not make contact with the basilar membrane 244, and (iii) the stimulation elements 148 are in close proximity to the modiolar wall (e.g., if the array 146 is pre-curved) or the stimulation elements 148 are distant from the modiolar wall (e.g., if the array 146 is not pre-curved).

[0040] However, the stimulation assembly 118, including the array 146, can experience various damaging forces under certain circumstances. For example, duringinsertion and / or extraction of the array 146, tensile forces can cause damage (e.g., breakage) of the signal conduits (e.g., electrical wire leads; optical waveguides) of the stimulation assembly 118 that extend from the stimulator unit 120, through the lead region 220 to the stimulation elements 148 or can cause detachment of the signal conduits from the stimulation elements 148. In addition, the stimulation assembly 118 can experience twisting (e.g., rotation about the longitudinal axis 322) due to torsional forces (e.g., during insertion) which can move the stimulation elements 148 from predetermined implantation positions.

[0041] FIGs. 5A-5D schematically illustrate portions of various example apparatus 300 comprising an assembly 310 (e.g., stimulation assembly 118; internal component 144) in accordance with certain implementations described herein. The assembly 310 is configured to be implanted on or within a recipient and comprises an elongate body 320, at least one element 330 (e.g., stimulation element 148), at least one signal conduit 340, and at least one reinforcement element 350. The elongate body 320 has a longitudinal axis 322 and comprises a flexible material 324. The at least one element 330 faces outwardly from the body 320 and is configured to be in operative communication with a portion of the recipient (e.g., tissue and / or bodily fluid of the recipient’s body). The at least one signal conduit 340 is in operative connection with the at least one element 330 and is enclosed by the flexible material 324 and extends along a length in a direction substantially parallel to the longitudinal axis 322. The at least one reinforcement element 350 is enclosed by the flexible material 324 and extends along the length in the direction substantially parallel to the longitudinal axis 322. The at least one reinforcement element 350 comprises a plurality of recesses 360 distributed along the length and that contain the flexible material 324.

[0042] In certain implementations, the apparatus 300 further comprises a substantially straight sheath 260 (not shown in FIGs. 5A-5D) configured to contain the assembly 310. The sheath 260 can comprise a distal end portion 262 through which the assembly 310 is configured to be extended out of the sheath 260 (e.g., during an implantation process). The sheath 260 has sufficient rigidity to remain substantially straight and to constrain at least a portion of the assembly 310 within the sheath 260 also be substantially straight. For example, the body 320 is sufficiently flexible such that the longitudinal axis 322 of a first portion of the body 320 contained within the sheath 260 is substantially straight and thelongitudinal axis 322 of a second portion of the body 320 extended out from the end of the sheath 260 is substantially curved (see, e.g., FIGs. 4A-4F).

[0043] In certain implementations, when not constrained by the sheath 260, the body 320 has a substantially curved (e.g., spiral) shape with the longitudinal axis 322 of the portion of the body 320 curved in a direction in which the at least one element 330 faces. For example, the elements 330 can face inwardly towards a center of curvature of the body 320. The curvature of the body 320 can be configured to conform to the curvature of the canals 236 of the human cochlea 140 (e.g., the body 320 has a radius of curvature in a range of 2 millimeters to 5 millimeters).

[0044] FIG. 5 A is a perspective view of the assembly 310 with the at least one element 330, the at least one signal conduit 340, and the at least one reinforcement element 350 of a portion of an example apparatus 300 (e.g., excluding the body 320) in accordance with certain implementations described herein. FIGs. 5B and 5C are two cross-sectional views of the example assembly 310 of FIG. 5 A in first and second cross-sectional planes substantially perpendicular to the longitudinal axis 322 at first and second positions along the longitudinal axis 322, respectively. FIG. 5D is a cross-sectional view of another example assembly 310 in a cross-sectional plane substantially perpendicular to the longitudinal axis 322 and extending through a recess 360 and an element 330.

[0045] In certain implementations, the flexible material 324 of the body 320 comprise at least one elastomeric material. Examples of elastomeric materials compatible with certain implementations described herein include but are not limited to: silicone; silicone rubber; other biocompatible polymers. In certain implementations, the flexible material 324 encases (e.g., surrounds) the at least one signal conduit 340 (e.g., the body 320 is molded around the at least one signal conduit 340) or the body 320 comprises a tube in which the at least one signal conduit 340 is contained (e.g., the tube backfilled with the flexible material 324). As schematically illustrated by FIGs. 5B-5D, the body 320 can have a substantially rectangular shape in a cross-sectional plane substantially perpendicular to the longitudinal axis 322 with a first width Wi in a first direction (e.g., in a range of 0.1 millimeter to 0.5 millimeter; in a range of 0.2 millimeter to 0.4 millimeter) and a second width W2 in a second direction substantially perpendicular to the first width (e.g., in a range of 0.2 millimeter to 0.6 millimeter; in a range of 0.3 millimeter to 0.5 millimeter). Other shapes (e.g., substantiallycircular; oval; substantially square; polygonal; symmetric; asymmetric) and dimensions of the body 320 are also compatible with certain implementations described herein.

[0046] In certain implementations, the body 320 comprises a material containing at least one substance (e.g., medicament; drug; antimicrobial agent; anti-inflammatory agent; oto-protective agent; neuroregenerative agent; neurotropic agent; gene therapy agent) and is configured to controllably introduce (e.g., release; elute) the at least one substance into the recipient’s body (e.g., tissue; bodily fluid). For example, the body 320 can comprise a biodegradable material (e.g., hydrogel) having a plurality of pores containing the at least one substance, and the biodegradable material can be configured to degrade (e.g., dissolve) sometime after implantation, thereby releasing the at least one substance into the recipient’s tissue and / or bodily fluid after the assembly 310 has been implanted. For another example, the body 320 can be configured to selectively release the at least one substance in response to at least one of a temperature and a moisture content of the tissue and / or bodily fluid in which the assembly 310 has been implanted. The body 320 can have a sufficiently large surface area to release an efficacious amount of the at least one substance into the recipient’s body. Different portions of the body 320 can contain different substances.

[0047] In certain implementations, as schematically illustrated by FIGs. 5A, 5C, and 5D, the at least one element 330 comprises an array (e.g., two or more) of elements 330 (e.g., array 146 of stimulation elements 148) distributed along the longitudinal axis 322. Examples of elements 330 compatible with certain implementations described herein include but are not limited to: electrical electrodes, electrical contacts, optical emitters, and optical contacts. Upon being in operational communication with a portion of the recipient’s body, the elements 330 can be configured to apply stimulation signals (e.g., electrical signals; optical signals) to the portion of the recipient’s body (e.g., the cochlea 140) and / or to receive measurement signals (e.g., electrical signals; optical signals) from the portion of the recipient’s body. While FIGs. 5A, 5C, and 5D show five elements 330, other numbers of elements 330 (1, 2, 3, 4, 6, or more) are also compatible with certain implementations described herein.

[0048] In certain implementations, the at least one signal conduit 340 comprises one or more wires (e.g., platinum; platinum-iridium alloys). Each wire can have an outer diameter in a range of 0.01 millimeter to 1 millimeter (e.g., 0.02 millimeter) and an electrically insulating outer coating (e.g., plastic; thermoplastic; polyphenylsulfone or PPSU) having athickness in a range of 0.001 micron to 0.02 micron (e.g., 0.005 micron). In certain other implementations, the at least one signal conduit 340 comprises one or more optical fibers or waveguides (e.g., silica-based glass or plastic). The at least one signal conduit 340 can extend along a length in a direction substantially parallel to the longitudinal axis 322. For example, the at least one signal conduit 340 can be substantially straight and substantially parallel to the longitudinal axis 322 (e.g., along the longitudinal direction 221 of the second portion 224 of the lead region 220). For other examples, the at least one signal conduit 340 can be wavy (e.g., extend back and forth along a second direction substantially perpendicular to the longitudinal axis 322 while also extending along the direction substantially parallel to the longitudinal axis 322) or can be helixed around an axis substantially parallel to the longitudinal axis 322 (e.g., along the longitudinal direction 221 of the first portion 222 of the lead region 220). While FIGs. 5A-5D show five signal conduits 340, other numbers of signal conduits 340 (1, 2, 3, 4, 6, or more) are also compatible with certain implementations described herein.

[0049] In certain implementations, each of the at least one signal conduit 340 is operatively connected to a corresponding one of the at least one element 330 (e.g., stimulation elements 148 of the array 146). For example, the at least one signal conduit 340 can comprise a wire and the at least one element 330 can comprise an electrode connected (e.g., joined; soldered; welded; crimped) to the wire such that electrical stimulation signals can propagate along the wire to the electrode to the recipient’s body and / or electrical measurement signals can propagate from the electrode through the wire to circuitry (e.g., control circuitry) of the apparatus 300. For another example, the at least one signal conduit 340 can comprise an optical waveguide (e.g., fiber) and the at least one element 330 can comprise an optical element connected (e.g., joined; fused) to the optical waveguide such that optical stimulation signals can propagate along the optical waveguide to the optical element to the recipient’s body and / or optical measurement signals can propagate from the optical element through the optical waveguide to an optical sensor of circuitry (e.g., control circuitry) of the apparatus 300.

[0050] In certain implementations, the signal conduit 340 and / or the connection 342 of the signal conduit 340 with the corresponding element 330 are fragile (e.g., low tensile strength) such that a relatively small tensile force can damage (e.g., break) the signal conduit 340 and / or the connection 342. While the signal conduit 340 and the connection 342 are enclosed by (e.g., embedded or encased within) the flexible material 324 (e.g., silicone), theadditional tensile strength provided by the flexible material 324 can be insufficient to protect the signal conduit 340 and / or the connection 342 from damage (e.g., breakage) due to tensile forces on the assembly 310 generated during fabrication, during operation, and / or during manipulation of the assembly 310 (e.g., handling during an insertion process and / or during an extraction process). In addition, the flexible material 324 can be insufficient to inhibit twisting of the assembly 310 about the longitudinal axis 322 due to torsional forces during insertion, which can move the elements 330 from predetermined implantation positions.

[0051] In certain implementations, the at least one reinforcement element 350 (e.g., ribbon; strip; band; film) comprises at least one reinforcing material embedded in the body 320 and configured to provide structural reinforcement. The reinforcing material can be biocompatible and example reinforcing materials compatible with certain implementations described herein include but are not limited to: polymer; polyamide; mesh; fibers, cords, or strands; carbon fibers; silk; metal; platinum; metal alloy; nickel-titanium alloy (e.g., nitinol); shape-memory alloy. In certain implementations, the at least one reinforcement element 350 comprises a single contiguous reinforcement element 350 (e.g., extending over the array of elements 330 distributed along the longitudinal axis 322; see, e.g., FIG. 5A), while in certain other implementations, the at least one reinforcement element 350 comprises multiple reinforcement elements 350 that at least partially overlap one another.

[0052] The at least one reinforcement element 350 can have a thickness tin a range of 0.005 millimeter to 0.4 millimeter (e.g., 0.01 millimeter to 0.2 millimeter) and a width w in a range of 0.1 millimeter to 0.7 millimeter (e.g., 0.2 millimeter to 0.5 millimeter). The at least one reinforcement element 350 can have a cross-sectional area in a plane substantially perpendicular to the longitudinal axis 322 (see, e.g., FIGs. 5B-5D) that is larger than the cross- sectional area of the at least one signal conduit 340 in the plane. One or more recesses 360 of the plurality of recesses 360 can extend completely through the thickness t of the at least one reinforcement element 350 (see, e.g., FIGs. 5A, 5C, and 5D) or can extend only partly through the thickness t.

[0053] In certain implementations, the flexible material 324 has a first tensile strength, the at least one signal conduit 340 has a second tensile strength, and the at least one reinforcement element 350 has a third tensile strength that is greater than the first tensile strength and greater than the second tensile strength. The reinforcement element 350 can bepositioned sufficiently close to the at least one signal conduit 340 (e.g., spaced by less than 0.2 millimeter) to inhibit (e.g., resist, prevent, limit, reduce, or minimize) breakage of the at least one signal conduit 340 due to tensile forces applied to the assembly 310.

[0054] In certain implementations, the plurality of recesses 360 comprise pores or holes (e.g., laser-cut sections) extending at least partially through the at least one reinforcement element 350. While FIG. 5A shows the plurality of recesses 360 having substantially circular outer perimeters 362, other shapes are also compatible with certain implementations described herein (e.g., oval; substantially rectangular; substantially square; polygonal; symmetric; asymmetric). The recesses 360 can have widths (e.g., in a direction substantially perpendicular to the longitudinal axis 322) that are in a range of 10 microns to 0.4 millimeter (e.g., 10 microns to 50 microns; 0.1 millimeter to 0.4 millimeter; 30% to 80% of the width of the reinforcement element 350) and / or lengths (e.g., in a direction substantially parallel to the longitudinal axis 322) that are in a range of 10 microns to 0.4 millimeter (e.g., 10 microns to 50 microns; 0.1 millimeter to 1 millimeter). In certain implementations, at least two adjacent recesses 360 of the plurality of recesses 360 are spaced from one another by a center-to-center distance in a range of 0.1 millimeter to 1 millimeter (e.g., 0.6 millimeter to 0.8 millimeter).

[0055] In certain implementations, at least some of the plurality of recesses 360 are sized to allow the flexible material 324 to flow into the recesses 360 (e.g., during injection molding of the flexible material 324) and around a portion of the at least one reinforcement element 350 to encase the portion of the at least one reinforcement element 350. For a recess 360 that extends only partly through the thickness t, the flexible material 324 can completely fill the recess 360. The recesses 360 containing the flexible material 324 can serve as anchors of the reinforcement element 350 to the flexible material 324 to inhibit (e.g., resist, prevent, limit, reduce, or minimize) slippage along the longitudinal axis 322 of the reinforcement element 350 relative to the flexible material 324 during flexing of the assembly 310 and / or applying tensile forces to the assembly 310.

[0056] In certain implementations, none of the signal conduits 340 extend through the plurality of recesses 360. For example, as shown in FIGs. 5A-5C, the elements 330 are below the reinforcement element 350 and the signal conduits 340 remain below the reinforcement element 350 along the length of the reinforcement element 350. In certain other implementations, the reinforcement element 350 is between at least one of the elements 330and the corresponding at least one signal conduit 340, and the at least one signal conduit 340 extends through at least one recess 360. In certain implementations, the at least one element 330 is aligned with at least one recess 360 of the plurality of recesses 360 and the at least one signal conduit 340 extends into the at least one recess 360 (e.g., each signal conduit 340 can extend through a corresponding recess 360 to connect to the corresponding element 330). For example, as shown in FIG. 5D, a signal conduit 340 above the reinforcement element 350 can extend through a recess 360 to connect to the corresponding element 330 below the reinforcement element 350. The reinforcement element 350 can be positioned sufficiently close to the at least one connection 342 (e.g., spaced by less than 0.2 millimeter) to inhibit (e.g., resist, prevent, limit, reduce, or minimize) breakage of the at least one connection 342 due to tensile forces applied to the assembly 310.

[0057] FIGs. 6A-6E schematically illustrate top views of various example reinforcement elements 350 in accordance with certain implementations described herein. As shown in FIGs. 6A-6E, the at least one reinforcement element 350 comprises a strip having an outer perimeter 352. The example reinforcement elements 350 of FIGs. 6A-6E extend at least along a full length of the array of elements 330 (e.g., array 146 of stimulation elements 148) along the longitudinal axis 322 (e.g., extending beyond the full array length to extend along a portion of the signal conduits 340). For example, the at least one signal conduit 340 can extend from a basal portion of the assembly 310 to an apical portion of the assembly 310, and the reinforcement element 350 can have a first end portion 354 (e.g., in the apical portion of the assembly 310), a middle portion 356, and a second end portion 358 (e.g., in the basal portion of the assembly 310), as shown in FIGs. 6C-6E.

[0058] As shown in FIGs. 6A and 6C-6E, the plurality of recesses 360 comprises at least one hole extending through the reinforcement element 350 and having a hole perimeter 362 that does not intersect the outer perimeter 352 of the reinforcement element 350. As shown in FIG. 6B, the plurality of recesses 360 comprises at least one notch at the outer perimeter 352 (e.g., the at least one notch has a notch edge 364 that is part of the outer perimeter 352 of the reinforcement element 350).

[0059] In certain implementations, two or more recesses 360 of the plurality of recesses 360 are substantially identical to one another. For example, as shown in FIGs. 6A and 6B, all the recesses 360 are substantially identical to one another. In certainimplementations, two or more recesses 360 of the plurality of recesses 360 have substantially different shapes and / or sizes to one another. For example, as shown in FIGs. 6C-6E, the plurality of recesses 360 can comprise multiple sets of recesses 360, each set comprises recesses 360 that are substantially identical to one another and the recesses 360 of each set having different shapes and / or sizes from the recesses of at least one other set.

[0060] In certain implementations, the reinforcement element 350 has a width and / or a thickness that varies along the longitudinal axis 322. The width of the reinforcement element 350 in a direction substantially perpendicular to the longitudinal axis 322 can be tapered along the longitudinal axis 322. As shown in FIG. 6E, the first end portion 354 (e.g., a distal end portion; within an apical portion 228 of the assembly 310) has a first width wi, the middle portion 356 has a second width W2 that is greater than the first width wi, and the second end portion 358 (e.g., a proximal end portion; within a basal portion of the assembly 310) has a third width ws that is greater than the second width W2- While FIG. 6E shows the width varying along the longitudinal axis 322 in a step-wise manner, the width can vary continuously (e.g., monotonically) from the first end portion 354, along the middle portion 356, to the second end portion 358.

[0061] The thickness of the reinforcement element 350 (e.g., in a direction substantially perpendicular to the longitudinal axis 322) can vary (e.g., be non-uniform) along the longitudinal axis 322. For example, the reinforcement element 350 can have different thicknesses around the recesses 360 as compared to between the recesses 360. For another example, the first end portion 354 can have a first thickness h, the middle portion 356 (e.g., displaced from the first end portion 354) can have a second thickness t2 that is greater than the first thickness h, and the second end portion 358 (e.g., displaced from the middle portion 356) can have a third thickness ts that is greater than the second thickness t2). The thickness can vary either in a step- wise manner or continuously (e.g., monotonically). For another example, the reinforcement element 350 can comprise protrusions (e.g., bumps; ridges; corrugations) at various positions along the longitudinal axis 322 (e.g., between the recesses 360; between the elements 330). The thicknesses and / or protrusions can be configured to tailor the bending properties of the reinforcement element 350 (e.g., larger thicknesses or bumps making portions of the reinforcement element 350 less flexible; smaller thicknesses or ridges making portions of the reinforcement element 350 more flexible).

[0062] In certain implementations, various attributes of the reinforcement element 350 (e.g., widths; thicknesses; shapes; materials) and / or the plurality of recesses 360 (e.g., widths; lengths; shapes; patterns or distributions along the longitudinal axis 322) can be tailored to tune the flexibility of various portions of the reinforcement element 350 and / or the assembly 310. For example, as schematically illustrated by FIG. 6C, the recesses 360 of the first end portion 354 can have substantially larger areas than do the recesses 360 of the second end portion 358 such that the second end portion 358 (e.g., basal end portion) of the reinforcement element 350 is less flexible than is the first end portion 354 (e.g., apical end portion) of the reinforcement element 350. For another example, as schematically illustrated by FIG. 6D, the recesses 360 in a predetermined portion 357 of the reinforcement element 350 can have smaller areas than do the recesses 360 in neighboring portions (e.g., first end portion 354; middle portion 356), such that the portion 357 is less flexible (e.g., more resistant to bending) than are the neighboring portions. In certain such implementations, the less flexible portion 357 is in a section of the assembly 310 that is configured to be substantially straight (e.g., a straightened tip shape) and / or to provide other features (e.g., to tailor tip angle; to inhibit tip foldover; to increase mechanical strength of the portion; to serve as a partial stiffener of the portion).

[0063] In certain implementations, the at least one reinforcement element 350 has sufficient flexibility, ductility, and / or malleability to not appreciably impede the flexibility of the assembly 310 (e.g., during an insertion process) while having sufficient tensile strength to inhibit twisting of the assembly 310 during insertion and / or to protect the at least one signal conduit 340 and / or the at least one connection 342 from damage (e.g., breakage) due to tensile forces on the assembly 310 generated during fabrication, during operation, and / or during manipulation of the assembly 310 (e.g., handling during an insertion process and / or during an extraction process). For example, the assembly 310 can be sufficiently flexible to have a first configuration (see, e.g., FIGs. 4A-4B) in which the longitudinal axis 322 of an apical portion of the body 320 is substantially straight and a second configuration (see, e.g., FIGs. 4D-4F) in which the longitudinal axis 322 of the apical portion of the body 320 is substantially curved (e.g., having a radius of curvature in a range of 2 millimeters to 5 millimeters). With the reinforcement element 350 anchored to the flexible material 324 (e.g., by the flexible material 324 extending into the plurality of recesses 360), the at least one reinforcement element 350can inhibit (e.g., resist, prevent, limit, reduce, or minimize) expansion of the assembly 310 along the longitudinal axis 322 that could otherwise cause damage (e.g., breakage) of the at least one signal conduit 340 and / or the at least one connection 342.

[0064] FIG. 7 is a flow diagram of an example method 400 in accordance with certain implementations described herein. While the method 400 is described by referring to some of the structures of the example apparatus 300 described herein, other apparatus and systems with other configurations of components can also be used to perform the method 400 in accordance with certain implementations described herein. The method 400 can be used to fabricate a stimulation assembly of a cochlear implant that is configured to be at least partially inserted into a cochlea 140 of a recipient’s body.

[0065] In an operational block 410, the method 400 comprises accessing a plurality of electrical wires (e.g., signal conduits 340) extending along a longitudinal axis (e.g., longitudinal axis 322) and having end portions that are spaced from one another along the longitudinal axis. For example, as shown in FIG. 5 A, the end portions (e.g., connections 342) of the various signal conduits 340 are spaced from one another along the longitudinal axis 322.

[0066] In an operational block 420, the method 400 further comprises positioning a bendable reinforcing element (e.g., reinforcement element 350) adjacent to the plurality of electrical wires. The reinforcing element extends along the longitudinal axis and has a higher tensile strength than does the plurality of electrical wires. For example, the reinforcing element can have a first cross-sectional area in a plane substantially perpendicular to the longitudinal axis and the plurality of electrical wires can have a second cross-sectional area in the plane substantially perpendicular to the longitudinal axis, the first cross-sectional area greater than the second cross-sectional area.

[0067] In an operational block 430, the method 400 further comprises encasing the plurality of electrical wires and the reinforcing element in a resilient material (e.g., flexible material 324) to form a bendable assembly. The resilient material extends into orifices (e.g., holes; recesses 360) and / or indentations (e.g., notches; recesses 360) of the reinforcing element.

[0068] In certain implementations, the reinforcing element comprises a thermoplastic material (e.g., polyimide) and the thermoplastic material is heatset into a predetermined shape before or after integrating the thermoplastic material with the electricalwires and / or the electrodes. For example, a substantially flat and planar polyimide reinforcing element can at least partially retain a curved shape after being heated to cure the flexible material 324 (e.g., silicone) into a curved molded shape (e.g., compatible for use with a perimodiolar stimulation assembly). In this way, the shape retention of the assembly can be facilitated (e.g., enabling less silicone or softer silicone to be used to achieve the curved shape.

[0069] After said encasing, the reinforcing element can inhibit (e.g., resist, prevent, limit, reduce, or minimize) damage (e.g., breakage) of the plurality of electrical wires by tensile forces applied to the assembly and / or twisting of the plurality of electrical wires by torsional forces applied to the assembly.

[0070] In certain implementations, the method 400 further comprises affixing a plurality of electrodes (e.g., elements 330 configured to be in operable communication with the recipient’s body) to the end portions of the plurality of electrical wires. The end portions can be affixed to corresponding electrodes (e.g., via soldering, welding, or crimping) before at least a portion of said encasing and / or after at least a portion of said encasing. For example, after a first stage of silicone injection in which the electrical wires are encased in silicone with the end portions extending from the silicone, the end portions can be affixed to the corresponding electrodes, forming electrically conductive bonds between the end portions and the electrodes. After said affixing, a second stage of silicone injection can be performed in which the electrical wires and the reinforcing element are encased in silicone with the electrodes at least partially extending from the silicone. The reinforcing element can be above the wires (e.g., on an opposite side of the wires from the electrodes) or can be below the wires (e.g., on the same side of the wires as are the electrodes). In certain such implementations, the end portions can be placed into corresponding orifices of the reinforcing element and then affixed to the corresponding electrodes.

[0071] FIG. 8 is a flow diagram of an example method 500 in accordance with certain implementations described herein. While the method 500 is described by referring to some of the structures of the example apparatus 300 described herein, other apparatus and systems with other configurations of components can also be used to perform the method 500 in accordance with certain implementations described herein. The method 500 can be used to implant a stimulation assembly (e.g., straight; perimodiolar) of a cochlear implant at least partially into a cochlea 140 of a recipient’s body. While the example method 500 of FIG. 8implants an example flexible assembly (e.g., stimulation assembly 310) using an insertion element (e.g., tube or sheath 260 containing the flexible assembly; stylet or wire at least partially within the flexible assembly), in certain other implementations, other methods can insert other types of assemblies (e.g., straight) into other regions of the recipient’s body by other means.

[0072] In an operational block 510, the method 500 comprises accessing an apparatus (e.g., apparatus 300) comprising a flexible assembly (e.g., stimulation assembly 310) in mechanical communication with the insertion element (e.g., contained within the tube or sheath 260; surrounding at least a portion of the stylet or wire). For example, the flexible assembly can be a portion of an implantable device (e.g., a cochlear implant). The flexible assembly comprises a plurality of electrodes (e.g., elements 330), a plurality of wires (e.g., signal conduits 340) affixed to the plurality of electrodes, and a strip (e.g., substantially flat; reinforcement element 350) with a plurality of orifices (e.g., recesses 360) extending at least partially therethrough, the wires and the strip encased within a flexible material (e.g., flexible material 324) with the wires and the strip extending substantially parallel to one another, the flexible material within the plurality of orifices. For example, the apparatus comprising the flexible assembly (e.g., with an insertion element in mechanical communication with the flexible assembly) can be shipped and / or stored in a hermetically sealed container and said accessing can comprise opening the container and removing the apparatus from the container.

[0073] In an operational block 520, the method 500 further comprises inserting the flexible assembly at least partially into a region of a recipient’s body (e.g., cochlea 140). During said inserting, the method 500 can comprise using the strip to inhibit damage, caused by tensile forces applied to the flexible assembly, to the wires and / or to connections of the wires to the electrodes.

[0074] In certain implementations, said inserting is performed without additional structures or tools (e.g., freely inserted). In certain other implementations, the apparatus further comprises an insertion element (e.g., tube or sheath 260; stylet) in mechanical communication with the flexible assembly, and said inserting is performed using the insertion element. The flexible assembly can have a substantially straight shape within the tube or on the stylet and a coil shape outside the tube or off the stylet. For example, said inserting can comprise inserting (e.g., pushing) the insertion element at least partially into the region (e.g.,into tissue of the recipient’s body) in an operational block 522 and sliding the flexible assembly along the insertion element such that the flexible assembly extends at least partially into the region in an operational block 524. For example, said sliding can comprise extending (e.g., sliding) at least a portion of the flexible assembly (e.g., a portion of the array of stimulation electrodes) along the tube such that the flexible assembly extends out of a distal end of the tube into the cochlea 140. For another example, said sliding can comprise extending (e.g., sliding) at least a portion of the flexible assembly along the stylet such that the flexible assembly extends further into the region than does the stylet. During said sliding, the strip can inhibit (e.g., resist, prevent, limit, reduce, or minimize) damage (e.g., breakage), caused by tensile forces applied to the flexible assembly (e.g., stretching of the flexible assembly about the longitudinal axis 322), to the wires and / or to connections of the wires to the electrodes. In certain implementations, during said sliding, the strip can inhibit (e.g., resist, prevent, limit, reduce, or minimize) twisting of the wires (e.g., about the longitudinal axis 322) caused by torsional forces applied to the flexible assembly.

[0075] In certain implementations, the method 500 further comprises removing the insertion element from the recipient’s body after said sliding, with the flexible assembly remaining within the recipient’s body after said removing the insertion element. During said removing, the strip can inhibit (e.g., resist, prevent, limit, reduce, or minimize) damage (e.g., breakage) caused by tensile forces applied to the flexible assembly (e.g., stretching of the flexible assembly about the longitudinal axis 322) to the wires and / or to connections of the wires to the electrodes.

[0076] Although commonly used terms are used to describe the systems and methods of certain implementations for ease of understanding, these terms are used herein to have their broadest reasonable interpretations. Although various aspects of the disclosure are described with regard to illustrative examples and implementations, the disclosed examples and implementations should not be construed as limiting. Conditional language, such as, among others, "can," "could," "might," or "may," unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain implementations include, while other implementations do not include, certain features, elements and / or steps. Thus, such conditional language is not generally intended to imply that features, elements and / or steps are in any way required for one or more implementations orthat one or more implementations necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and / or steps are included or are to be performed in any particular implementation. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a nonexclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

[0077] It is to be appreciated that the implementations disclosed herein are not mutually exclusive and may be combined with one another in various arrangements. In addition, although the disclosed methods and apparatuses have largely been described in the context of conventional cochlear implants, various implementations described herein can be incorporated in a variety of other suitable devices, methods, and contexts. More generally, as can be appreciated, certain implementations described herein can be used in a variety of implantable medical device contexts.

[0078] Language of degree, as used herein, such as the terms “approximately,” “about,” “generally,” and “substantially,” represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” “generally,” and “substantially” may refer to an amount that is within ± 10% of, within ± 5% of, within ± 2% of, within ± 1 % of, or within ± 0.1% of the stated amount. As another example, the terms “generally parallel” and “substantially parallel” refer to a value, amount, or characteristic that departs from exactly parallel by ± 10 degrees, by ± 5 degrees, by ± 2 degrees, by ± 1 degree, or by ± 0.1 degree, and the terms “generally perpendicular” and “substantially perpendicular” refer to a value, amount, or characteristic that departs from exactly perpendicular by ± 10 degrees, by ± 5 degrees, by ± 2 degrees, by ± 1 degree, or by ± 0.1 degree. The ranges disclosed herein also encompass any and all overlap, sub-ranges, and combinations thereof. Language such as “up to,” “at least,” “greater than,” less than,” “between,” and the like includes the number recited. As used herein, the meaning of “a,” “an,” and “said” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “into” and “on,” unless the context clearly dictates otherwise.

[0079] While the methods and systems are discussed herein in terms of elements labeled by ordinal adjectives (e.g., first, second, etc.), the ordinal adjective are used merely as labels to distinguish one element from another (e.g., one signal from another or one circuit from one another), and the ordinal adjective is not used to denote an order of these elements or of their use.

[0080] The invention described and claimed herein is not to be limited in scope by the specific example implementations herein disclosed, since these implementations are intended as illustrations, and not limitations, of several aspects of the invention. Any equivalent implementations are intended to be within the scope of this invention. Indeed, various modifications of the invention in form and detail, in addition to those shown and described herein, will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the claims. The breadth and scope of the invention should not be limited by any of the example implementations disclosed herein, but should be defined only in accordance with the claims and their equivalents.

Claims

WHAT IS CLAIMED IS:

1. An apparatus comprising: an assembly configured to be implanted on or within a recipient, the assembly comprising: an elongate body having a longitudinal axis and comprising a flexible material; at least one element facing outwardly from the body, the at least one element configured to be in operative communication with a portion of the recipient; at least one signal conduit in operative connection with the at least one element, the at least one signal conduit enclosed by the flexible material and extending along a length in a direction substantially parallel to the longitudinal axis; and at least one reinforcement element enclosed by the flexible material and extending along the length in the direction substantially parallel to the longitudinal axis, the at least one reinforcement element comprising a plurality of recesses distributed along the length and that contain the flexible material.

2. The apparatus of claim 1, wherein the flexible material comprises silicone and the at least one reinforcement element comprises at least one material selected from the group consisting of: polymer; polyamide; mesh; fibers; carbon fibers; silk; metal; platinum; metal alloy; nickel-titanium alloy.

3. The apparatus of claim 1 or claim 2, wherein the flexible material has a first tensile strength, the at least one signal conduit has a second tensile strength, and the at least one reinforcement element has a third tensile strength greater than the first tensile strength and greater than the second tensile strength.

4. The apparatus of any of claims 1 to 3, wherein the at least one reinforcement element comprises a strip having an outer perimeter.

5. The apparatus of claim 4, wherein the plurality of recesses comprises at least one hole extending through the strip and having a hole perimeter that does not intersect the outer perimeter.

6. The apparatus of claim 4, wherein the plurality of recesses comprises at least one notch at the outer perimeter.

7. The apparatus of any of claims 4 to 6, wherein two or more recesses of the plurality of recesses are substantially identical to one another.

8. The apparatus of any of claims 4 to 7, wherein two or more recesses of the plurality of recesses have substantially different shapes and / or sizes to one another.

9. The apparatus of any of claims 4 to 8, wherein a width of the strip in a direction substantially perpendicular to the longitudinal axis is tapered along the longitudinal axis.

10. The apparatus of any of claims 4 to 9, wherein a first portion of the strip has a first thickness in a second direction substantially perpendicular to the longitudinal axis and a second portion of the strip has a second thickness in the second direction, the second portion displaced from the first portion along the longitudinal axis.

11. The apparatus of any of claims 4 to 10, wherein a basal end portion of the strip is less flexible than is an apical end portion of the strip.

12. The apparatus of any of claims 1 to 11, wherein the assembly is sufficiently flexible to have a first configuration in which the longitudinal axis of an apical portion of the body is substantially straight and a second configuration in which the longitudinal axis of the apical portion of the body is substantially curved.

13. The apparatus of claim 12, wherein the longitudinal axis of the apical portion of the body of the second configuration has a radius of curvature in a range of 2 millimeters to 5 millimeters.

14. The apparatus of any of claims 1 to 13, wherein the at least one element comprises an array of elements distributed along the longitudinal axis and the at least one reinforcement element comprises a single contiguous reinforcement element.

15. The apparatus of any of claims 1 to 14, wherein the at least one element is aligned with at least one recess of the plurality of recesses and the at least one signal conduit extends into the at least one recess.

16. A method comprising: accessing a plurality of electrical wires extending along a longitudinal axis and having end portions that are spaced from one another along the longitudinal axis;positioning a bendable reinforcing element adjacent to the plurality of electrical wires, the reinforcing element extending along the longitudinal axis and having a higher tensile strength than does the plurality of electrical wires; and encasing the plurality of electrical wires and the reinforcing element in a resilient material to form a bendable assembly, the resilient material extending into orifices and / or indentations of the reinforcing element.

17. The method of claim 16, wherein, after said encasing, the reinforcing element inhibits breakage of the plurality of electrical wires by tensile forces applied to the assembly.

18. The method of claim 16 or claim 17, wherein, after said encasing, the reinforcing element inhibits twisting of the plurality of electrical wires by torsional forces applied to the assembly.

19. The method of any of claims 16 to 18, wherein the reinforcing element has a first cross-sectional area in a plane substantially perpendicular to the longitudinal axis and the plurality of electrical wires has a second cross-sectional area in the plane substantially perpendicular to the longitudinal axis, the first cross-sectional area greater than the second cross-sectional area.

20. The method of any of claims 16 to 19, further comprising affixing a plurality of electrodes to the end portions of the plurality of electrical wires.

21. The method of claim 20, wherein said affixing comprises: prior to at least a portion of said encasing, placing the end portions of the plurality of electrical wires into corresponding orifices of the reinforcing element; and forming electrically conductive bonds between the end portions and the electrodes.

22. The method of any of claims 16 to 21, wherein the assembly comprises a stimulation assembly of a cochlear implant, the assembly configured to be at least partially inserted into a cochlea of a recipient’s body.

23. A method comprising: accessing an apparatus comprising a flexible assembly comprising a plurality of electrodes, a plurality of wires affixed to the plurality of electrodes, and a strip with a plurality of orifices extending at least partially therethrough, the wires and the stripencased within a flexible material with the wires and the strip extending substantially parallel to one another, the flexible material within the plurality of orifices; inserting the flexible assembly at least partially into a region of a recipient’s body; and during said inserting, using the strip to inhibit damage, caused by tensile forces applied to the flexible assembly, to the wires and / or to connections of the wires to the electrodes.

24. The method of claim 23, wherein the apparatus further comprises an insertion element in mechanical communication with the flexible assembly, said inserting comprising: inserting the insertion element at least partially into the region; and sliding the flexible assembly along the insertion element such that the flexible assembly extends at least partially into the region; and wherein said using the strip occurs during said sliding.

25. The method of claim 24, wherein the insertion element comprises a tube, said accessing comprises accessing the apparatus with the flexible assembly contained within the tube, said inserting comprises inserting the tube containing the flexible assembly at least partially into the region, and said sliding comprises sliding the flexible assembly along the tube such that the flexible assembly extends out of the tube through a distal end of the tube.

26. The method of claim 24, wherein the insertion element comprises a stylet, said accessing comprises accessing the apparatus with the stylet at least partially within the flexible assembly, said inserting further comprises inserting the flexible assembly at least partially into the region, and said sliding comprises sliding the flexible assembly along the stylet such that the flexible assembly extends further into the region than does the stylet.

27. The method of claim 24 or claim 25, wherein the flexible assembly has a substantially straight shape within the tube or on the stylet and a coil shape outside the tube or off the stylet.

28. The method of any of claims 24 to 27, further comprising removing the insertion element from the recipient’s body after said sliding, wherein the flexible assembly remains within the recipient’ s body after said removing.

29. The method of claim 28, further comprising, during said removing, using the strip to inhibit damage caused by tensile forces applied to the flexible assembly to the wires and / or to connections of the wires to the electrodes.

30. The method of any of claims 24 to 29, further comprising, during said sliding, using the strip to inhibit twisting of the wires caused by torsional forces applied to the flexible assembly.

31. The method of any of claims 23 to 30, wherein said accessing comprises opening a container and removing the apparatus from the container.

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