Patent ID: 12207054

DETAILED DESCRIPTION

Certain embodiments described herein provide an implantable transducer assembly (e.g., an implantable assembly comprising at least one microphone; an implantable middle ear assembly comprising at least one actuator; an implantable assembly comprising both at least one microphone and at least one actuator) that includes a diaphragm on a wall of the hermetically sealed assembly without a joint seam (e.g., laser weld) in proximity to (e.g., in contact with) the diaphragm that would otherwise adversely affect the performance or vibrational characteristics of the diaphragm. In addition, the absence of such a joint seam advantageously avoids fabrication problems associated with attaching a fragile diaphragm to the wall of the assembly and with undesirable leakage through the joint seam. The diaphragm of certain embodiments is fabricated by micromachining (e.g., laser micromachining) a wall of the assembly to reduce a thickness of at least a portion of the wall, thereby forming a unitary wall that comprises the diaphragm (e.g., the diaphragm is integral and/or monolithic with other wall portions surrounding the diaphragm).

The teachings detailed herein are applicable, in at least some embodiments, to any type of auditory prosthesis utilizing 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. Embodiments can include any type of auditory prosthesis that can utilize the teachings detailed herein and/or variations thereof. Certain such embodiments can be referred to as “partially implantable,” “semi-implantable,” “mostly implantable,” “fully implantable,” or “totally implantable” auditory prostheses. In some embodiments, the teachings detailed herein and/or variations thereof can be utilized in other types of prostheses beyond auditory prostheses.

FIG.1is a perspective view of an example cochlear implant auditory prosthesis100implanted in a recipient in accordance with certain embodiments described herein. The example auditory prosthesis100is shown inFIG.1as comprising an implanted stimulator unit120(e.g., an actuator) and a microphone assembly124that is external to the recipient (e.g., a partially implantable cochlear implant). An example auditory prosthesis100(e.g., a totally implantable cochlear implant; a mostly implantable cochlear implant) in accordance with certain embodiments described herein can replace the external microphone assembly124shown inFIG.1with a subcutaneously implantable microphone assembly124, as described more fully herein.

As shown inFIG.1, the recipient has an outer ear101, a middle ear105, and an inner ear107. In a fully functional ear, the outer ear101comprises an auricle110and an ear canal102. An acoustic pressure or sound wave103is collected by the auricle110and is channeled into and through the ear canal102. Disposed across the distal end of the ear canal102is a tympanic membrane104which vibrates in response to the sound wave103. This vibration is coupled to oval window or fenestra ovalis112through three bones of middle ear105, collectively referred to as the ossicles106and comprising the malleus108, the incus109, and the stapes111. The bones108,109, and111of the middle ear105serve to filter and amplify the sound wave103, causing the oval window112to articulate, or vibrate in response to vibration of the tympanic membrane104. This vibration sets up waves of fluid motion of the perilymph within cochlea140. Such fluid motion, in turn, activates tiny hair cells (not shown) inside the cochlea140. Activation of the hair cells causes appropriate nerve impulses to be generated and transferred through the spiral ganglion cells (not shown) and auditory nerve114to the brain (also not shown) where they are perceived as sound.

As shown inFIG.1, the example auditory prosthesis100comprises one or more components which are temporarily or permanently implanted in the recipient. The example auditory prosthesis100is shown inFIG.1with an external component142which is directly or indirectly attached to the recipient's body, and an internal component144which is temporarily or permanently implanted in the recipient (e.g., positioned in a recess of the temporal bone adjacent auricle110of the recipient). The external component142typically comprises one or more sound input elements (e.g., an external microphone124) for detecting sound, a sound processing unit126(e.g., disposed in a Behind-The-Ear unit), a power source (not shown), and an external transmitter unit128. In the illustrative embodiments ofFIG.1, the external transmitter unit128comprises an external coil130(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 coil130. The external coil130of the external transmitter unit128is part of an inductive radio frequency (RF) communication link with the internal component144. The sound processing unit126processes the output of the microphone124that is positioned externally to the recipient's body, in the depicted embodiment, by the recipient's auricle110. The sound processing unit126processes the output of the microphone124and generates encoded signals, sometimes referred to herein as encoded data signals, which are provided to the external transmitter unit128(e.g., via a cable). As will be appreciated, the sound processing unit126can utilize digital processing techniques to provide frequency shaping, amplification, compression, and other signal conditioning, including conditioning based on recipient-specific fitting parameters.

The power source of the external component142is configured to provide power to the auditory prosthesis100, where the auditory prosthesis100includes a battery (e.g., located in the internal component144, or disposed in a separate implanted location) that is recharged by the power provided from the external component142(e.g., via a transcutaneous energy transfer link). The transcutaneous energy transfer link is used to transfer power and/or data to the internal component144of the auditory prosthesis100. 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 component142to the internal component144. During operation of the auditory prosthesis100, the power stored by the rechargeable battery is distributed to the various other implanted components as needed.

The internal component144comprises an internal receiver unit132, a stimulator unit120, and an elongate electrode assembly118. In some embodiments, the internal receiver unit132and the stimulator unit120are hermetically sealed within a biocompatible housing. The internal receiver unit132comprises an internal coil136(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 coil136. The internal receiver unit132and the stimulator unit120are hermetically sealed within a biocompatible housing, sometimes collectively referred to as a stimulator/receiver unit. The internal coil136receives power and/or data signals from the external coil130via a transcutaneous energy transfer link (e.g., an inductive RF link). The stimulator unit120generates electrical stimulation signals based on the data signals, and the stimulation signals are delivered to the recipient via the elongate electrode assembly118.

The elongate electrode assembly118has a proximal end connected to the stimulator unit120, and a distal end implanted in the cochlea140. The electrode assembly118extends from the stimulator unit120to the cochlea140through the mastoid bone119. In some embodiments, the electrode assembly118may be implanted at least in the basal region116, and sometimes further. For example, the electrode assembly118may extend towards apical end of cochlea140, referred to as cochlea apex134. In certain circumstances, the electrode assembly118may be inserted into the cochlea140via a cochleostomy122. In other circumstances, a cochleostomy may be formed through the round window121, the oval window112, the promontory123, or through an apical turn 147 of the cochlea140.

The elongate electrode assembly118comprises a longitudinally aligned and distally extending array146of electrodes or contacts148, sometimes referred to as electrode or contact array146herein, disposed along a length thereof. Although the electrode array146can be disposed on the electrode assembly118, in most practical applications, the electrode array146is integrated into the electrode assembly118(e.g., the electrode array146is disposed in the electrode assembly118). As noted, the stimulator unit120generates stimulation signals which are applied by the electrodes148to the cochlea140, thereby stimulating the auditory nerve114.

WhileFIG.1schematically illustrates an auditory prosthesis100utilizing an external component142comprising an external microphone124, an external sound processing unit126, and an external power source, in certain other embodiments, one or more of the microphone124, sound processing unit126, and power source are implantable on or within the recipient (e.g., within the internal component144). For example, the auditory prosthesis100can have each of the microphone124, sound processing unit126, 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 prosthesis100can 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”).

FIG.2schematically illustrates a perspective view of an example fully implantable auditory prosthesis200(e.g., fully implantable middle ear implant or totally implantable acoustic system), implanted in a recipient, utilizing an acoustic actuator in accordance with certain embodiments described herein. The example auditory prosthesis200ofFIG.2comprises a biocompatible implantable assembly202(e.g., comprising an implantable capsule) located subcutaneously (e.g., beneath the recipient's skin and on a recipient's skull). WhileFIG.2schematically illustrates an example implantable assembly202comprising a microphone, in other example auditory prostheses200, a pendant microphone can be used (e.g., connected to the implantable assembly202by a cable). The implantable assembly202includes a signal receiver204(e.g., comprising a coil element) and an acoustic transducer206(e.g., a microphone comprising a diaphragm and an electret or piezoelectric transducer) that is positioned to receive acoustic signals through the recipient's overlying tissue. The implantable assembly202may further be utilized to house a number of components of the fully implantable auditory prosthesis200. For example, the implantable assembly202can include an energy storage device and a signal processor (e.g., a sound processing unit). Various additional processing logic and/or circuitry components can also be included in the implantable assembly202as a matter of design choice.

For the example auditory prosthesis200shown inFIG.2, the signal processor of the implantable assembly202is in operative communication (e.g., electrically interconnected via a wire208) with an actuator210(e.g., comprising a transducer configured to generate mechanical vibrations in response to electrical signals from the signal processor). In certain embodiments, the example auditory prosthesis100,200shown inFIGS.1and2can comprise an implantable microphone assembly, such as the microphone assembly206shown inFIG.2. For such an example auditory prosthesis100, the signal processor of the implantable assembly202can be in operative communication (e.g., electrically interconnected via a wire) with the microphone assembly206and the stimulator unit of the main implantable component120. In certain embodiments, at least one of the microphone assembly206and the signal processor (e.g., a sound processing unit) is implanted on or within the recipient.

The actuator210of the example auditory prosthesis200shown inFIG.2is supportably connected to a positioning system212, which in turn, is connected to a bone anchor214mounted within the recipient's mastoid process (e.g., via a hole drilled through the skull). The actuator210includes a connection apparatus216for connecting the actuator210to the ossicles106of the recipient. In a connected state, the connection apparatus216provides a communication path for acoustic stimulation of the ossicles106(e.g., through transmission of vibrations from the actuator210to the incus109).

During normal operation, ambient acoustic signals (e.g., ambient sound) impinge on the recipient's tissue and are received transcutaneously at the microphone assembly206. Upon receipt of the transcutaneous signals, a signal processor within the implantable assembly202processes the signals to provide a processed audio drive signal via wire208to the actuator210. As will be appreciated, the signal processor may utilize digital processing techniques to provide frequency shaping, amplification, compression, and other signal conditioning, including conditioning based on recipient-specific fitting parameters. The audio drive signal causes the actuator210to transmit vibrations at acoustic frequencies to the connection apparatus216to affect the desired sound sensation via mechanical stimulation of the incus109of the recipient.

The subcutaneously implantable microphone assembly202is configured to respond to auditory signals (e.g., sound; pressure variations in an audible frequency range) by generating output signals (e.g., electrical signals; optical signals; electromagnetic signals) indicative of the auditory signals received by the microphone assembly202, and these output signals are used by the auditory prosthesis100,200to generate stimulation signals which are provided to the recipient's auditory system. To compensate for the decreased acoustic signal strength reaching the microphone assembly202by virtue of being implanted, the diaphragm of an implantable microphone assembly202is configured to provide higher sensitivity than are external non-implantable microphone assemblies (e.g., by using diaphragms that are larger than diaphragms for external non-implantable microphone assemblies).

The example auditory prostheses100shown inFIG.1utilizes an external microphone124and the auditory prosthesis200shown inFIG.2utilizes an implantable microphone assembly206comprising a subcutaneously implantable acoustic transducer. In certain embodiments described herein, the auditory prosthesis100utilizes one or more implanted microphone assemblies on or within the recipient. In certain embodiments described herein, the auditory prosthesis200utilizes one or more microphone assemblies that are positioned external to the recipient and/or that are implanted on or within the recipient, and utilizes one or more acoustic transducers (e.g., actuator210) that are implanted on or within the recipient. In certain embodiments, an external microphone assembly can be used to supplement an implantable microphone assembly of the auditory prosthesis100,200. Thus, the teachings detailed herein and/or variations thereof can be utilized with any type of external or implantable microphone arrangement, and the acoustic transducers shown inFIGS.1and2are merely illustrative.

FIG.3schematically illustrates an example apparatus300in accordance with certain embodiments described herein. The apparatus300comprises a biocompatible housing310configured to be implanted within a recipient and comprising a unitary wall320. The unitary wall320comprises a first wall portion322and a second wall portion324surrounding a perimeter326of the first wall portion322. The first wall portion322is sufficiently flexible to transmit vibrations between an outer region311outside the housing310and an inner region312within the housing310.

In certain embodiments, the second wall portion324has an inner surface325which at least partially bounds the inner region312within the housing310. In certain embodiment, the unitary wall320is integral and/or monolithic with another one or more walls or wall portions of the housing310(e.g., a third wall portion328) at a periphery of the housing310.

In certain embodiments, the apparatus300comprises an acoustic transducer configured to be implanted within the recipient and operatively coupled to an auditory prosthesis used by the recipient. For example, the apparatus300can comprise a microphone124(e.g., subcutaneous microphone or middle ear microphone) or implantable microphone assembly202configured to convert received vibrations and/or pressure changes within the recipient's body, based on sound waves incident to the recipient's body, into electrical or optical signals transmitted to other portions of an auditory prosthesis100,200(e.g., as schematically shown inFIGS.1and2). The apparatus300of certain such embodiments is configured to detect vibrations and/or pressure changes from at least a partially functional portion of the recipient's auditory system (e.g., middle ear structures and/or cavities; inner ear structures and/or cavities) and to convert the detected vibrations and/or pressure changes into electrical signals. In certain embodiments, the apparatus300comprises an acoustic transducer (e.g., microphone) integrated within the housing310, and the housing310is a casing of a cochlear implant auditory prosthesis. For example, the casing of the cochlear implant auditory prosthesis can include the microphone as well as other components of the cochlear implant auditory prosthesis (e.g., stimulation electronics and sound processing electronics), such that the cochlear implant auditory prosthesis is contained in only the single implantable casing (e.g., with the microphone diaphragm formed in the top shells of the cochlear implant casing).

For another example, the apparatus300can comprise an implantable actuator210configured to be mechanically coupled to a portion of the recipient's auditory system and to generate acoustical vibrations in response to electrical signals received from other portions (e.g., the implantable assembly202) of the auditory prosthesis200with these acoustical vibrations transmitted to the recipient's auditory system (e.g., as schematically shown inFIG.2). The apparatus300of certain such embodiments is configured to receive electrical signals and to generate vibrations and/or pressure changes that are applied to at least a partially functional portion of the recipient's auditory system (e.g., middle ear structures and/or cavities; inner ear structures and/or cavities). In certain embodiments, the apparatus300comprises at least one acoustic transducer (e.g., at least one microphone) and at least one actuator integrated within a common implantable housing310.

In certain embodiments, the housing310comprises an enclosure (e.g., casing; chassis; can) comprising a biocompatible material (e.g., titanium; titanium alloy) and is configured to contain one or more transducers (e.g., acoustic transducers; mechanical-electrical transducers) and electronic circuitry (e.g., electronic circuit elements, including but not limited to one or more microprocessors, electrical insulation, electrical shielding, one or more electrical feedthroughs) in the inner region312within the housing310. For example, the housing310can bound the inner region312within the housing310and can hermetically seal the inner region312from the outer region311outside the housing310(e.g., can be substantially impenetrable to air and body fluids).

WhileFIG.3schematically illustrates an example housing310that has a substantially tubular shape (e.g., cylindrical with a cylindrical third wall portion328with a circular cross-section in a plane perpendicular to a longitudinal axis of the housing310), the housing310can have any shape, including but not limited to: tubular; non-tubular; cylindrical; non-cylindrical; parallelepiped; geometric cross-sectional shapes (e.g., circular; elliptical; rectangular; square; polygonal); irregular cross-sectional shapes. WhileFIG.3schematically illustrates the housing310having a corner330(e.g., 90 degrees) between an edge of the second wall portion324and an edge of the third wall portion328, in certain other embodiments, the housing310has a smooth contour (e.g., no corner) between the second wall portion324and the third wall portion328.

As used herein, the term “unitary” has its broadest reasonable meaning, which includes but is not limited to, forming a single or uniform entity; integral; monolithic. For example, the first wall portion322and the second wall portion324of the unitary wall320can be integral with one another, monolithic with one another, and/or in mechanical communication with one another without a joint seam between the first wall portion322and the second wall portion324. The unitary wall320can also be integral and/or monolithic with other walls or other wall portions of the housing310. For example, as shown inFIG.3, the unitary wall320can be integral and/or monolithic with the third wall portion328(e.g., the second wall portion324of the unitary wall320can be integral with, monolithic with, and/or in mechanical communication with the third wall portion328without a joint seam between the second wall portion324and the third wall portion328).

In certain embodiments, the unitary wall320of the housing310is planar, while in certain other embodiments, the unitary wall320is curved (e.g., bowed; concave; convex), and/or can have one or more protrusions or recesses. WhileFIG.3schematically illustrates an example first wall portion322that has a circular perimeter326and an example second wall portion324that has a circular perimeter (e.g., at the corner330), each of the first wall portion322and the second wall portion324can have any shape, including but not limited to: geometric (e.g., elliptical, rectangular, square, polygonal); irregular.

In certain embodiments, the first wall portion322has a first thickness between an inner side of the first wall portion322(e.g., facing the inner region312within the housing310) and an outer side of the first wall portion322(e.g., facing the outer region311outside the housing310), and the second wall portion324has a second thickness between an inner side of the second wall portion324and an outer side of the second wall portion324. In certain embodiments, the first thickness (e.g., in a range of 10 microns to 100 microns; in a range of 10 microns to 50 microns; in a range of 15 microns to 30 microns; 20 microns; 25 microns) is less than the second thickness (e.g., in a range greater than 100 microns). While the example first wall portion322ofFIG.3is substantially uniform across the area of the first wall portion322(e.g., the first wall portion322has a uniform thickness across the area of the first wall portion322), in certain other embodiments, the first wall portion322has a non-uniform thickness. In certain embodiments, at least a portion of the first wall portion322is configured to flex (e.g., elastically deform) in response to forces applied to the first wall portion322(e.g., by vibrations and/or pressure changes applied to either the outer side or the inner side of the first wall portion322).

In certain embodiments, the inner region312within the housing310can be configured to contain a transducer (e.g., acoustic transducer; mechanical-electrical transducer; microphone assembly124,202; actuator210) of the apparatus300which is in mechanical communication with the first wall portion322(e.g., with the housing310bounding the inner region312and hermetically sealing the inner region312from the outer region311). For example, the electronic circuitry of the transducer can be mechanically coupled to the first wall portion322such that vibrations received on a first side of the first wall portion322are transmitted to a second side of the first wall portion322. In certain such embodiments in which the acoustic transducer comprises a microphone (e.g., electret; magnetic; dynamic; piezoelectric; optical; electromechanical), vibrations received at the outer surface of the first wall portion322are transmitted to the inner surface of the first wall portion322and are converted into electrical signals by the transducer. In certain other such embodiments in which the acoustic transducer comprises an actuator, the transducer generates and applies vibrations to the inner surface of the first wall portion322, which are transmitted via the outer surface of the first wall portion322to a portion of the recipient's auditory system.

FIGS.4A-4Cschematically illustrate various views of another example apparatus300in accordance with certain embodiments described herein. The housing310ofFIGS.4A-4Ccomprises a body410having a parallelepiped shape with a length (e.g., in a range of 5 millimeters to 15 millimeters; 9 millimeters), a width (e.g., in a range of 1 millimeter to 6 millimeters; 3.5 millimeters), and a height (e.g., in a range of 1 millimeter to 6 millimeters; 3.5 millimeters). As schematically illustrated inFIGS.4A-4C, the second wall portion324of the unitary wall320has a rectangular edge mechanically coupled to an edge of the third wall portion328, forming the corner330, and the first wall portion322has a circular perimeter326surrounded by the second wall portion324.

The body410has at least one opening412configured to provide access to the inner region312of the housing310during assembly of the apparatus300(e.g., to allow the electronic circuitry of the transducer to be inserted within the housing310and to connect the transducer to the first wall portion322). In certain embodiments, the at least one opening412provides “line-of-sight” access to the inner surface325of the second wall portion324(e.g., the inner surface325of the second wall portion324is viewable through the at least one opening412). The housing310further comprises at least one lid414configured to be joined (e.g., soldered; brazed; welded; laser welded) to the body410(e.g., hermetically sealing the opening412). The joint seams between the body410and the at least one lid414are spaced away from the first wall portion322.FIG.4Ais a perspective view of the example apparatus300prior to the at least one lid414being joined to the body410in accordance with certain embodiments described herein.

In certain embodiments, the housing310further comprises at least one electrical feedthrough420in electrical communication with the electronic circuitry of the transducer. For example, the at least one electrical feedthrough420can extend through and be electrically insulated from a wall422of the body410, spaced away from the first wall portion322, such that the at least one electrical feedthrough420is configured to transmit electrical signals between the inner region312within the housing310and the outer region311outside the housing310. In certain embodiments, the wall422comprises a plate or other structure through which the at least one electrical feedthrough420extend, and the wall422is configured to be joined (e.g., soldered; brazed; welded; laser welded) to the body410to hermetically seal a corresponding opening (not shown) of the body410with the at least one electrical feedthrough420extending between the inner region312and the outer region311.

FIG.4Bis a top view of the example apparatus300ofFIG.4Ashowing a portion of the inner region312through the opening412prior to the at least one lid414being joined to the body410in accordance with certain embodiments described herein. Within the housing310, the at least one electrical feedthrough420is electrically coupled to the electronic circuitry430, and the electronic circuitry430is electrically coupled to the transducer440which is mechanically (e.g., pneumatically) coupled to an inner side of the first wall portion322. For example, the transducer440can be acoustically sealed against the inner side of the first wall portion322by a sealing element (e.g., epoxy; O-ring; double-sided adhesive tape). In certain embodiments, the apparatus300comprises at least one electrically insulating material configured to electrically insulate one or both of the electronic circuitry430and the transducer440from the body410and/or at least one electrically shielding material configured to provide electromagnetic shielding to one or both of the electronic circuitry430and the transducer440.

In certain embodiments in which the apparatus300comprises an implantable microphone assembly, electrical signals are generated by the microphone (e.g., the transducer440and the circuitry430) and are transmitted via the at least one electrical feedthrough420to other portions of the acoustic prosthesis (e.g., to a stimulator unit120of a cochlear implant auditory prosthesis). In certain other such embodiments in which the apparatus300comprises an actuator (e.g., a portion of a middle ear implant auditory prosthesis), the electrical signals are transmitted via the at least one electrical feedthrough420to the electrical circuitry430and the transducer440within the housing310from other portions of the acoustic prosthesis (e.g., from an implantable assembly202of a middle ear implant auditory prosthesis) and are used to control the vibrations of the first wall portion322to be transmitted to a portion of the recipient's auditory system. Examples of the body410, at least one electrical feedthrough420, electronic circuitry430, and transducer440in accordance with certain embodiments described herein are described in U.S. Pat. No. 9,533,143.

FIG.4Cschematically illustrates a cross-sectional view and a front view of the example unitary wall320ofFIG.4Ain accordance with certain embodiments described herein. As schematically illustrated byFIG.4C, the inner surface325of the second wall portion324at least partially bounds the inner region312within the housing310, and the unitary wall320is integral and/or monolithic with another one or more walls or wall portions of the housing310(e.g., a third wall portion328) at a periphery of the housing310.

In certain embodiments, as schematically illustrated byFIGS.4A and4C, a central portion450of the first wall portion322has a third thickness (e.g., in a range greater than 100 microns) that is larger than the first thickness of a peripheral portion452of the first wall portion322, the peripheral portion452surrounding the central portion450. The central portion450of certain embodiments is configured to be mechanically coupled to additional components (e.g., an elongate member460) configured to transmit vibrations between the first wall portion322and a predetermined portion of the recipient's auditory system. For example, as schematically illustrated inFIG.4C, the central portion450comprises a recess configured to receive and be mechanically coupled (e.g., by soldering; brazing; welding; laser welding) to the first end portion462of the elongate member460. In certain such embodiments, the peripheral portion452of the first wall portion322is configured to flex (e.g., elastically deform) in response to forces applied to the first wall portion322(e.g., by vibrations and/or pressure changes applied to either the outer side or the inner side of the first wall portion322) while the central portion450is not configured to flex in response to these forces but is configured to move due to the flexing of the peripheral portion452.

In certain embodiments, the apparatus300further comprises an elongate member460(e.g., ball wire; rod) in mechanical communication with the first wall portion322. A first end portion462of the elongate member460is mechanically coupled to the first wall portion322(e.g., to the central portion450of the first wall portion322) and a second end portion464of the elongate member460is configured to be mechanically coupled to an at least partially functioning portion of the recipient's auditory system. In certain embodiments in which the apparatus300comprises an implantable microphone assembly, vibrations from the at least partially functioning portion of the recipient's auditory system (e.g., generated by received sound signals) are transmitted via the elongate member460to the first wall portion322. In certain embodiments in which the apparatus300comprises an actuator (e.g., a portion of a middle ear implant auditory prosthesis), vibrations of the first wall portion322(e.g., generated by the transducer440) are transmitted via the elongate member460to the at least partially functioning portion of the recipient's auditory system. The elongate member460of certain embodiments comprises a biocompatible material (e.g., titanium; titanium alloy; plastic; ceramic; glass), has a length (e.g., in a range of 3 millimeters to 10 millimeters; 6 millimeters), and a width (e.g., in a range of 0.2 millimeter to 1 millimeter; 0.4 millimeter). WhileFIGS.4A-4Cschematically illustrate the elongate member460as being straight with a substantially uniform cross-section in a plane perpendicular to a longitudinal axis of the elongate member460, in certain other embodiments, the elongate member460is at least partially curved and/or has a non-uniform cross-section. Examples of elongate members460in accordance with certain embodiments described herein are described in U.S. Pat. Appl. Publ. No. 2013/0116497A1.

FIG.5is a flow diagram of an example method500in accordance with certain embodiments described herein.FIGS.6A and6Bschematically illustrate two example configurations for performing the method500in accordance with certain embodiments described herein. While the example method500is described herein by referring to the example apparatus300ofFIGS.3,4A-4C, and6A-6B, other apparatuses are also compatible with the example method500in accordance with certain embodiments described herein. For example, the method500described herein can be applied to any of a variety of implantable medical devices that utilize a diaphragm formed on a wall of the device.

In an operational block510, the method500comprises providing at least a portion of a biocompatible housing310configured to be implanted within a recipient. The portion of the biocompatible housing310comprises a wall320. In an operational block520, the method500further comprises, while a first portion322of the wall320is mechanically coupled to a second portion324of the wall320, integrally forming a diaphragm on the wall320by thinning the first portion322of the wall320to have a first thickness less than a second thickness of the second portion324of the wall320.

In certain embodiments, providing at least a portion of the biocompatible housing310comprises providing a body410comprising the wall320.FIGS.6A and6Bschematically illustrate an example body410in accordance with certain embodiments described herein. The body410comprises one or more walls (including the wall320) comprising a biocompatible material (e.g., titanium; titanium alloy), which generally surround at least a portion of an inner region312within the body410. For clarity, inFIGS.6A and6B, the wall320is shown as shaded while the other walls are shown as unshaded.

The body410can include one or more openings412through one or more of the walls of the body410. For example, the body410ofFIG.6Ahas an opening412on a wall610of the body410different from the wall320but adjacent to the wall320(e.g., sharing a corner with the wall320; a top wall of the body410), and the body410ofFIG.6Bhas an opening412aon a wall610adjacent to the wall320and has an opening412bon a wall620opposite to and non-adjacent to the wall320(e.g., not sharing a corner with the wall320; a rear wall of the body410). For example, the opening412bthrough the wall620can be configured to be sealed by a corresponding plate or other structure comprising the at least one electrical feedthrough420. In certain embodiments in which the body410has a smooth contour (e.g., no corner) between the wall320and any adjacent walls, the perimeter of the opening412is spaced sufficiently away from the first portion324of the wall320such that any joint seam subsequently formed while sealing (e.g., hermetically) the opening412does not affect the performance or vibrational characteristics of the diaphragm formed on the wall320. WhileFIG.6Bshows the body410having two openings412a,412b, in certain other embodiments, the body410has only a single opening412bthrough which access to the inner region312is provided during fabrication.

In certain embodiments, thinning the first portion322of the wall320comprises etching, mechanical machining, or electrical discharge machining the first portion322to remove material from a surface of the first portion322to reduce a thickness of the first portion322(e.g., such that the first portion322is sufficiently flexible to transmit vibrations between the outer region311and the inner region312). In certain other embodiments, thinning the first portion322of the wall320comprises irradiating the first portion322with laser light640to remove material from a surface of the first portion322to reduce a thickness of the first portion322(e.g., laser micromachining) (e.g., such that the first portion322is sufficiently flexible to transmit vibrations between the outer region311and the inner region312). For example, as schematically illustrated inFIG.6A, an outer surface630of the first portion322of the wall320(e.g., facing an outer region311outside the body410or the housing310) is irradiated with laser light640such that material is removed from the outer surface630. For another example, as schematically illustrated inFIG.6B, an inner surface632of the first portion322of the wall320(e.g., facing an inner region312bounded at least partially by the body410or within and bounded by the housing310) is irradiated with laser light640such that material is removed from the surface of the inner side632. As schematically illustrated inFIG.6B, the laser light640can be directed through the opening412of the body410or housing310to impinge the inner surface632of the wall320.

In certain embodiments, the laser light is generated by at least one laser (e.g., CO2laser; Nd laser; Nd:YAG laser; excimer laser; fiber laser) and is configured to controllably remove material (e.g., via ablation, vaporization, and/or melting) from a surface impinged by the laser light. For example, the laser light can be either continuous-wave (CW) or pulsed, and can comprise at least one wavelength (e.g., less than 20 microns; less than 10 microns; less than 1 micron; 10.6 microns for CO2laser; 1.064 microns for Nd:YAG laser), an average power (e.g., less than 100 W; less than 10 W; less than 1 W; less than 100 mW; less than 10 mW), a duty cycle (e.g., less than 50%; less than 20%; less than 10%), and a temporal pulse width (e.g., less than 1 millisecond; less than 100 microseconds; less than 10 microseconds; less than 1 microsecond; less than 100 nanoseconds; less than 10 nanoseconds; less than 1 nanosecond; less than 100 picoseconds; less than 10 picoseconds; less than 1 picosecond; less than 100 femtoseconds; less than 10 femtoseconds), and can have a spot size (e.g., less than 1 millimeter; less than 100 microns; less than 10 microns; less than 1 micron). In certain embodiments, one or both of the laser light640and the body410can be moved relative to one another to irradiate selected portions of the wall320, thereby removing material from the first portion322. For example, one or both of the laser and the body410can be mounted on a controllably-movable stage with a predetermined resolution of motion. In certain embodiments, thinning the first portion322of the wall320is performed while not thinning the second portion324of the wall320(e.g., only removing material from the first portion322and not removing material from the second portion324).

In certain embodiments, the method500further comprises placing electronic circuitry430and a transducer440within the inner region312, mechanically coupling the transducer440to the inner surface632of the wall320, and mechanically coupling the elongate member460to the outer surface630of the wall320. In certain embodiments, the method500further comprises hermetically sealing the opening412(e.g., after irradiating the inner surface632of the wall320) by placing a lid414and/or plate over the opening412and joining (e.g., soldering; brazing; welding; laser welding) the lid414and/or plate to the body410. For example, the plate can comprise the at least one electrical feedthrough420, and the plate can be joined to the body410such that the at least one electrical feedthrough420is mechanically coupled to the housing310and extends between the inner region312and the outer region311. The method500can further comprise mechanically coupling the at least one electrical feedthrough420to the electronic circuitry430. In certain embodiments, thinning the first portion322of the wall320is performed before at least one of: mechanically coupling the transducer440to the inner surface632of the wall320and mechanically coupling the elongate member460to the outer surface630of the wall320.

Certain embodiments described herein advantageously improve the fabrication of an implantable transducer assembly (e.g., implantable middle ear transducer assembly) by one or more of the following: reducing manufacturing time, reducing manufacturing overhead, reducing number of parts utilized, reducing cost of goods sold (COGS), avoiding expensive laser welding processes of the diaphragm, avoiding breaches of the housing to form the diaphragm. Certain embodiments described herein advantageously reduce the risk of hermeticity breaches of the implantable transducer assembly and/or damage during fabrication, thereby making the assembly more robust and cheaper to manufacture. Certain embodiments described herein advantageously provide a platform for implantable transducer assemblies by creating a generic housing comprises an integrated vibration port. Certain embodiments described herein can be advantageously applied to housings of any size or shape and can advantageously fabricate diaphragms of any size or shape, either by removing material from an outer surface of the housing and/or from an inner surface of the housing.

It is to be appreciated that the embodiments disclosed herein are not mutually exclusive and may be combined with one another in various arrangements.

The invention described and claimed herein is not to be limited in scope by the specific example embodiments herein disclosed, since these embodiments are intended as illustrations, and not limitations, of several aspects of the invention. Any equivalent embodiments 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 embodiments disclosed herein, but should be defined only in accordance with the claims and their equivalents.