Hearing loss, which may be due to many different causes, is generally of two types: conductive and sensorineural. Sensorineural hearing loss is due to the absence or destruction of the hair cells in the cochlea that transduce sound signals into nerve impulses. Various hearing prostheses are commercially available to provide individuals suffering from sensorineural hearing loss with the ability to perceive sound. One example of a hearing prosthesis is a cochlear implant.
Conductive hearing loss occurs when the normal mechanical pathways that provide sound to hair cells in the cochlea are impeded, for example, by damage to the ossicular chain or the ear canal. Individuals suffering from conductive hearing loss may retain some form of residual hearing because the hair cells in the cochlea may remain undamaged.
Individuals suffering from conductive hearing loss typically receive an acoustic hearing aid. Hearing aids rely on principles of air conduction to transmit acoustic signals to the cochlea. In particular, a hearing aid typically uses an arrangement positioned in the recipient's ear canal or on the outer ear to amplify a sound received by the outer ear of the recipient. This amplified sound reaches the cochlea causing motion of the perilymph and stimulation of the auditory nerve.
In contrast to hearing aids, which rely primarily on the principles of air conduction, certain types of hearing prostheses commonly referred to as cochlear implants convert a received sound into electrical stimulation. The electrical stimulation is applied to the cochlea, which results in the perception of the received sound.
In an exemplary embodiment, there is a device, comprising an implantable sensor having a membrane displaceable in response to physical phenomena outside the sensor, wherein the device is configured to equalize a static pressure difference between an ambient environment and a back volume of the sensor.
In another exemplary embodiment, there is a device, comprising an implantable microphone having a membrane displaceable in response to a change in a phenomena of fluid in a cochlea induced by ambient sound, the membrane forming a portion of a boundary of a back volume of the microphone, wherein the device is configured to expand and contract a size of the volume of the back volume independent of movement of the membrane.
In another exemplary embodiment, there is a device comprising an implantable static pressure equalization system configured to equalize an internal pressure of an apparatus with a static pressure of an ambient environment, the apparatus being configured to sense a dynamic phenomenon in a recipient, the system including at least one diaphragm bounding a volume, wherein the diaphragm is configured to deflect in response to a change in the static pressure, thereby adjusting the size of the volume bounded by the diaphragm, wherein the system is configured such that the volume is placed in fluid communication with the apparatus, and wherein the diaphragm is sheltered by at least two substantially rigid components located on opposite sides of the diaphragm in a direction normal to a maximum diameter of the diaphragm.
In another exemplary embodiment, there is a method, comprising, automatically maintaining a neutral position of at least one of (i) a membrane of an implanted microphone having a front volume and a back volume separated by the membrane and fluidically isolated from one another in response to a change in pressure of the front volume induced by a change in pressure of an ambient environment in which the microphone is located or (ii) a flexible diaphragm of a pressure receptor that hermetically isolates an internal volume in fluid communication with the microphone with an ambient environment by automatically adjusting the size of the back volume to at least substantially equalize the pressure of at least one of the back volume and the pressure of a combined front and back volume with the pressure of the ambient environment. In an exemplary embodiment, the method is executed in a cochlear implant implanted in a recipient, wherein the changes in the ambient environment correspond to changes in a pressure of fluid inside the cochlea of the recipient. In an exemplary embodiment, at least a portion of the back volume is located remote from the front volume.
Embodiments of the present invention are described below with reference to the attached drawings, in which:
The recipient has an outer ear 101, a middle ear 105 and an inner ear 107. Components of outer ear 101, middle ear 105 and inner ear 107 are described below, followed by a description of cochlear implant 100.
In a fully functional ear, outer ear 101 comprises an auricle 110 and an ear canal 102. An acoustic pressure or sound wave 103 is collected by auricle 110 and channeled into and through ear canal 102. Disposed across the distal end of ear canal 102 is a tympanic membrane 104 which vibrates in response to sound wave 103. This vibration is coupled to oval window 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. Bones 108, 109 and 111 of middle ear 105 serve to filter and amplify sound wave 103, causing oval window 112 to articulate, or vibrate in response to vibration of tympanic membrane 104. This vibration sets up waves of fluid motion of the perilymph within cochlea 140. Such fluid motion, in turn, activates tiny hair cells (not shown) inside of 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.
As shown, cochlear implant 100 comprises one or more components which are temporarily or permanently implanted in the recipient. Cochlear implant 100 is shown in
In the illustrative arrangement of
Cochlear implant 100 comprises an internal energy transfer assembly 132 which may be positioned in a recess of the temporal bone adjacent auricle 110 of the recipient. As detailed below, internal energy transfer assembly 132 is a component of the transcutaneous energy transfer link and receives power and/or data from external device 142. In the illustrative embodiment, the energy transfer link comprises an inductive RF link, and internal energy transfer assembly 132 comprises a primary internal coil 136. Internal coil 136 is typically a wire antenna coil comprised of multiple turns of electrically insulated single-strand or multi-strand platinum or gold wire.
Cochlear implant 100 further comprises a main implantable component 120 and an elongate stimulating assembly 118. In embodiments of the present invention, internal energy transfer assembly 132 and main implantable component 120 are hermetically sealed within a biocompatible housing. In embodiments of the present invention, main implantable component 120 includes a sound processing unit (not shown) to convert the sound signals received by the implantable microphone in internal energy transfer assembly 132 to data signals. Main implantable component 120 further includes a stimulator unit (also not shown) which generates electrical stimulation signals based on the data signals. The electrical stimulation signals are delivered to the recipient via elongate stimulating assembly 118.
Elongate stimulating assembly 118 has a proximal end connected to main implantable component 120, and a distal end implanted in cochlea 140. Stimulating assembly 118 extends from main implantable component 120 to cochlea 140 through mastoid bone 119. In some embodiments stimulating assembly 118 may be implanted at least in basal region 116, and sometimes further. For example, stimulating assembly 118 may extend towards apical end of cochlea 140, referred to as cochlea apex 134. In certain circumstances, stimulating assembly 118 may be inserted into cochlea 140 via a cochleostomy 122. In other circumstances, a cochleostomy may be formed through round window 121, oval window 112, the promontory 123 or through an apical turn 147 of cochlea 140.
Stimulating assembly 118 comprises a longitudinally aligned and distally extending array 146 of electrodes 148, disposed along a length thereof. As noted, a stimulator unit generates stimulation signals which are applied by stimulating contacts 148, which, in an exemplary embodiment, are electrodes, to cochlea 140, thereby stimulating auditory nerve 114. In an exemplary embodiment, stimulation contacts can be any type of component that stimulates the cochlea (e.g., mechanical components, such as piezoelectric devices that move or vibrate, thus stimulating the cochlea (e.g., by inducing movement of the fluid in the cochlea), electrodes that apply current to the cochlea, etc.). Embodiments detailed herein will generally be described in terms of an electrode assembly 118 utilizing electrodes as elements 148. It is noted that alternate embodiments can utilize other types of stimulating devices. Any device, system or method of stimulating the cochlea can be utilized in at least some embodiments.
As noted, cochlear implant 100 comprises a totally implantable prosthesis that is capable of operating, at least for a period of time, without the need for external device 142. Therefore, cochlear implant 100 further comprises a rechargeable power source (not shown) that stores power received from external device 142. The power source may comprise, for example, a rechargeable battery. During operation of cochlear implant 100, the power stored by the power source is distributed to the various other implanted components as needed. The power source may be located in main implantable component 120, or disposed in a separate implanted location.
It is noted that the teachings detailed herein and/or variations thereof can be utilized with a non-totally implantable prosthesis. That is, in an alternate embodiment of the cochlear implant 100, the cochlear implant 100 is a traditional hearing prosthesis.
While various aspects of the present invention are described with reference to a cochlear implant (whether it be a device utilizing electrodes or stimulating contacts that impart vibration and/or mechanical fluid movement within the cochle), it will be understood that various aspects of the embodiments detailed herein are equally applicable to other stimulating medical devices having an array of electrical simulating electrodes such as auditory brain implant (ABI), functional electrical stimulation (FES), spinal cord stimulation (SCS), penetrating ABI electrodes (PABI), and so on. Further, it should be appreciated that the present invention is applicable to stimulating medical devices having electrical stimulating electrodes of all types such as straight electrodes, peri-modiolar electrodes and short/basilar electrodes. Also, various aspects of the embodiments detailed herein and/or variations thereof are applicable to devices that are non-stimulating and/or have functionality different from stimulating tissue, such as for, example, any intra-body dynamic phenomenon (e.g., pressure, or other phenomenon consistent with the teachings detailed herein) measurement/sensing, etc., which can include use of these teachings to sense or otherwise detect a phenomenon at a location other than the cochlea (e.g., within a cavity containing the brain, the heart, etc.). Additional embodiments are applicable to bone conduction devices, Direct Acoustic Cochlear Stimulators/Middle Ear Prostheses, and conventional acoustic hearing aids. Any device, system or method of evoking a hearing percept can be used in conjunction with the teachings detailed herein.
Electrode array assembly 390 includes a cochlear implant electrode array 310 and an apparatus 320 configured to sense a phenomenon of the fluid in a cochlea. In an exemplary embodiment, electrode array assembly 390 has some and/or all of the functionality of electrode array assembly 190, where electrode array assembly 190 corresponds to a state-of-the-art electrode array assembly and/or variations thereof and/or an earlier model electrode array assembly. By way of example only and not by way of limitation, electrode array assembly 390 includes any electrode array 310 comprising a plurality of electrodes 148. The electrode array assembly 390 is configured such that the electrodes 148 of the electrode array 310 are in and/or can be placed in signal communication with the receiver stimulator 180.
In some embodiments, the phenomenon sensed by the apparatus 320 is a pressure of the fluid in the cochlea and/or a change in pressure of the fluid in the cochlea (a dynamic pressure). In an exemplary embodiment of
More particularly, apparatus 320 includes a physical phenomenon receptor 330 which is in fluid communication with conduit 340 which in turn is in fluid communication with sensor assembly 350.
In an exemplary embodiment, the receptor 330 is a pressure receptor. In a non-mutually exclusive fashion, the receptor 330 can be a vibration receptor. As noted above, receptor 330 is a physical phenomenon receptor. Accordingly, in some embodiments, receptor 330 corresponds to any type of receptor that can function as a physical phenomenon receptor providing that the teachings detailed herein and/or variations thereof can be practiced with that receptor.
In the exemplary embodiment of the figures, the receptor 330 is a titanium cylinder having a closed end (distal end) and an end (proximal end) that is open via a port. The port provides fluid communication between the inside of the cylinder and the outside of the cylinder. Receptor 330 includes four diaphragms 334 arrayed about the longitudinal surface of the cylinder. In the embodiments of the figures, the diaphragms 334 cover through holes that extend through the longitudinal surface of the cylinder. The diaphragms 334 hermetically seal these holes. The diaphragms 334 configured to deflect or otherwise move as a result of pressure variations and/or vibrations impinging thereupon that are communicated thereto via the cochlea fluid. This causes pressure fluctuations within the receptor 330. In an exemplary embodiment, this is because the deflections of one or more diaphragms 334 change the volume within the receptor 330. Depending on the fluid that fills or otherwise is located in the receptor 330, vibrations can travel through the diaphragms from the cochlea fluid into the fluid inside the receptor 330.
Conduit 340 extends from receptor 330 to sensor assembly 350, and includes lumen 324 which places the inside of receptor 330 into fluid communication with the sensor assembly 350. In an exemplary embodiment, conduit 340 is a tube. Conduit 340 can be flexible and/or rigid. In an exemplary embodiment conduit 340 can be made of titanium. In an exemplary embodiment, in addition to the functionality of placing the receptor into fluid communication with the sensor assembly, conduit 340 has the functionality of maintaining a set/specific/control distance between the sensor assembly 350 (or more accurately, components of the sensor assembly 350 detail below) and the receptor 330. Still further, an exemplary embodiment, conduit 340 provides the transition between the intra-cochlea region 188 and the proximal region 186 of the electrode array assembly 390. In at least some embodiments, while not depicted in the figures, conduit 340 can include other components that have utilitarian value with respect to the tissue-electrode array interface (e.g. ribs, occluding features, antiviral and/or bacterial features etc.).
With respect to the embodiments detailed above, pressure variations and/or vibrations in the cochlea fluid that impinge upon the diaphragms deflect the diaphragms such that pressure fluctuations exist in/vibrations travel thorough the fluid-filled volume (e.g., a gas-filled volume, such as an inert gas such as argon-filled volume, etc.) that corresponds to the interior of the receptor 330 and the conduit 340, as well as the pertinent portions of the sensor assembly 350, in which resides a transducer that converts these pressure fluctuations/vibrations into another form of energy (e.g., electrical signal, an optical signal etc.), which in turn is ultimately provided (directly and/or indirectly) to the receiver stimulator 180 of the cochlear implant 100, which in turn interprets this energy as sound information Some details of the sensor assembly 350 will now be described.
Housing 352 can be a hollow cylindrical body made of titanium or another biocompatible material. The housing 352 can be made of one or more such materials (e.g. it can be made of entirely titanium and/or a titanium alloy, or can be made out of different materials). The sensor assembly 350 includes a MEMS (micro-electro-mechanical system) condenser microphone 354 including a membrane 357 that bifurcates the volume 353 into a front volume (the volume to the right (relative to the orientation of
The sensor assembly 350 further includes a perforated backplate 356 which in at least some embodiments is part of the microphone 354 (it is noted that in some alternate embodiments, the back plate 356 is located in the front volume (i.e., to the right of the membrane 357)). In the embodiment of the figures, the microphone 354 is in fluid communication with the lumen 324 of conduit 340, which as noted above is in fluid communication with the interior of the receptor 330. Thus, in the embodiments of the figures, pressure changes inside the receptor 330 are fluidly communicated to the microphone 354.
In an exemplary embodiment, membrane 357 (also sometimes referred to as a diaphragm) is a pressure-sensitive membrane (diaphragm) that is etched directly onto a silicon chip. In this regard, the microphone falls within the rubric of “pressure sensor.” The pressure changes that occur inside receptor 330 as a result of the pressure changes in the cochlea fluid are sensed by the microphone 354. The microphone outputs the signals via electrical leads 355 to a pre-amplifier 358. The pre-amplifier 358, in at least some embodiments, amplifies the signal and/or lowers the noise of the microphone 354 and/or the output impedance of the microphone 354 that exists, in at least some embodiments, owing to the relatively large output impedance of the microphone 354. This lowering of the noise is relative to that which would be the case in the absence of the amplifier. It is noted that in some alternate embodiments, the preamplifier 358 is part of the MEMS microphone 354. In an exemplary embodiment, an A/D converter is integrated in the sensor assembly 350. In the embodiment depicted in
In an exemplary embodiment, the microphone is a MQM 31692 or a 32325 Knowles microphone or an ADMP504 microphone. (Any microphone that can enable the teachings detailed herein and/or variations thereof to be practiced can be utilized in at least some embodiments. In an exemplary embodiment, the microphone 354 (sensor) is a so-called air backed sensor. That said, in at least some exemplary embodiments, a so-called water backed sensor (or liquid backed sensor) can be utilized. Accordingly in an exemplary embodiment, the medium which fills the interior cavity of the apparatus 320 can be a liquid.
It is further noted that in alternate embodiments, the microphone 354 can be a MEMS microphone of a different species than the condenser microphone. In an exemplary embodiment, any MEMS-based membrane type sensor can be utilized such as by way of example, a capacitive, an optical, a piezoelectric membrane type sensor etc. Further, in an alternate embodiment, the microphone 354 need not be MEMS based. Any device, system, and/or method, that can transduce the pressure changes inside the closed system of the apparatus 320 can be utilized in at least some embodiments, providing that the teachings detailed herein and/or variations thereof can be practiced.
The microphone 354 transduces the pressure variations and outputs the transduced energy via electrical lead(s) 399. Via electrical lead(s) 399, the output of the microphone is received by the receiver stimulator 180 of the cochlear implant 100. In some embodiments, the sound processor of the cochlear implant 100 (the sound processor is typically located in the receiver stimulator 180 or in an implantable sound processor housing remote from the receiver stimulator 180 but in signal communication with the stimulator 180) receives the output of the microphone 354 or signal indicative of the output of the microphone 354, and processes that output into a signal (including a plurality of signals) that are used by the stimulator 180 to formulate output signal to the electrode array of the electrode array assembly to electrically stimulate the cochlea and evoke a hearing percept. In the exemplary embodiment as just described, the electrode array assembly 390 is utilized in a so-called totally implantable hearing prosthesis. Thus, in an exemplary embodiment, there is a method of evoking a hearing percept by electrically stimulating the cochlea based on a physical phenomenon within the cochlea, where, in at least some embodiments, the method is executed without intervening input from a component outside the recipient (i.e. no intervening input between the physical phenomenon within the cochlea and the stimulation of the cochlea). Alternatively, in an alternate exemplary embodiment, a signal indicative of the sensed physical phenomenon within the cochlea is outputted to an external component of the hearing prosthesis, which includes a sound processor, which sound processor processes the signal into a signal that is then transcutaneously transmitted to the receiver stimulator 180 inside the recipient where the receiver stimulator 180 utilizes that signal to output a signal to the electrode array of the electrode array assembly to electrically stimulate the cochlea and evoke a hearing percept. Additional details of such exemplary methods and systems and devices to execute such methods are detailed further below.
It is noted that while the embodiment of
As noted above, the back volume 359 of the sensor assembly 350 includes a system which is initially indicated as black box 410. In an exemplary embodiment, black box 410 enables a static pressure difference between (i) an ambient environment (e.g., the static pressure in the cochlea of the recipient/the static pressure impinging upon the diaphragms 334) and/or a pressure in the front volume of the sensor (which is impacted by the ambient environment) and (ii) the back volume of the sensor and/or a combined front and back volume to be equalized, wherein both the back volume and the front volume are hermetically sealed/closed volumes relative to the ambient environment and, in some instances, relative to each other (in some embodiments as will be detailed below, the front and back volumes are in fluid communication with each other). In some embodiments, the sensor assembly itself is a single unit that enables one or more or all of the aforementioned static pressure equalization(s), while in other embodiments, the sensor assembly comprises two or more units, one or more of which enable one or more or all of the aforementioned static pressure equalization(s).
In this vein,
Additional details of some embodiments will be described below, but first, some exemplary high-level functionalities will be described in view of the aforementioned functional schematic of
As noted above, the fluid in the cochlea undergoes pressure variations caused by vibrations impinging upon the outside of the cochlea and transmission therein (e.g., through the oval window via ossicular vibrations (natural and/or prosthetically based), through the round window in scenarios where for whatever reason the round window transfers vibrations into the cochlea, and/or through any other part of the cochlea such that the cochlear fluid vibrates in a manner that the teachings detailed herein and/or variations thereof can be practiced). In at least some exemplary scenarios, the vibrations that impinge upon the outside of the cochlea and are transmitted therein are vibrations based on an ambient sound that would otherwise ultimately evoke a hearing percept in a normal hearing person. These vibrations cause pressure variations within the cochlea. This type of pressure variation results in what will be hereinafter referred to as dynamic pressure of the cochlea. It is this type of pressure variation (dynamic pressure) that the sensor assembly 350 detailed above and variations thereof sense to output a signal indicative of sound that can be utilized to evoke a hearing percept.
Conversely, pressure within the cochlea will change as a result of changes in the ambient environment, at least changes that are different than a change resulting from the phenomenon of sound. Hereinafter, the pressure within the cochlea resulting from such conditions is referred to as static pressure. Thus, dynamic pressure is a pressure relative to static pressure.
By way of example only and not by way of limitation, changes in atmospheric conditions in which a recipient of the sensor assembly 350 resides can result in a change in the pressure of the fluid inside the cochlea. One extreme exemplary example of this can occur when a recipient travels in a pressurized aircraft (e.g. a commercial jetliner having, for example, transatlantic capabilities, such as by way of example only and not by way of limitation, a Boeing 777 or an Airbus 380). It is routine for the cabin of the aircraft to be pressurized at an air pressure corresponding to the average air pressure at 8,000 feet above sea level. That is, the pressure inside the cabin is substantially lower than that which occurs at sea level. Over a sufficiently lengthy period of time (where lengthy is a relative term), the pressure inside the cochlea will equalize to, or at least reduce towards (at least in a significant manner that can impact the performance of the sensor assembly 350 as will be detailed below), the air pressure of the cabin. Another example of this can occur when a recipient swims underwater in general, and dives into the water in particular. That said, standard changes in atmospheric condition resulting from a passage of a low-pressure front or a high-pressure front (relative terms), ground travel resulting in altitude changes (common, for example, in the Western portions of North and South America) and other changes can also change the static pressure inside the cochlea. Moreover, in some instances, physiological changes of the recipient can result in changes in the static pressure of the front volume of the sensor assembly 350. By way of example only and not by way of limitation, in at least some embodiments, a hydration level of a recipient can potentially influence the static pressure within the cochlea.
Also it is noted that by static pressure changes, it is meant pressure changes that change relatively slowly. By way of example only and not by way of limitation, a pressure change resulting from a diver diving into a pool to a depth of 2 or 3 meters and then immediately ascending to the surface would not constitute a static pressure change. Conversely, if the diver were to remain at the depth of 2 or 3 meters for a period of time (a minute or more, for example, the change in ambient pressure would result in a static pressure change). In this regard, the affirmation scenario recognizes that in at least some embodiments implementing the teachings detailed herein and or variations thereof, a given equalization structure can require a lag time for pressure equalization. In an exemplary embodiment, this lag time is on the order of minutes, albeit in some embodiments the lag time is on the order of seconds.
Because the diaphragms 334 are deflected due to changes in pressure (both static and dynamic pressure), the aforementioned static pressure changes within the cochlea will influence the static pressure within the front volume of the sensor assembly 350, and within the combined front volume and back volume in embodiments where there is fluid communication between the two. Because the sensor 350 is configured such that dynamic pressure changes within the receptor 330 (e.g., resulting from sound) influence the membrane 357 of the microphone 354 (hence how the microphone 354 operates), static pressure changes within the receptor 330, and thus the front volume of the microphone 354, will cause the membrane 357 to be displaced from a neutral position.
That is, in at least some exemplary embodiments, the internal pressure of the front volume and/or back volume of the sensor assembly 350 is set to an initial internal pressure. In an exemplary embodiment, this is about 0.8 bars, which is average pressure at about 100 meters above sea level. The pressure can be set to be different depending on where the recipient spends most of his or her time (e.g., at sea level, in locations of heightened altitude, such as the city of Denver in the United States, which is about 1,200 meters above sea level, etc. that is the pressure is set to the average ambient atmospheric pressure). It is noted that in an exemplary embodiment, the internal pressure is set to a pressure that places the membrane 357 at a neutral position. In this regard, in an exemplary embodiment entails pressurizing or depressurizing the back volume to a pressure that places the membrane 357 at a neutral position for a specific ambient pressure.
It is noted that the teachings detailed herein and/or variations thereof can be practiced without the pressures in the front volume, the back volume and/or in the cochlea being equal. Embodiments can be practiced where there is an initial pressure difference, and this pressure difference is generally maintained during changes in the ambient environment so that the changes do not significantly impact the performance of the sensor assembly 350. Depending on the initial static pressure differential between the front volume and the back volume, a certain degree of deflection of the membrane 357 might result. In some embodiments, the deflection will be zero (e.g., where the front volume pressure and the back volume pressure are effectively equal). In other embodiments, the deflection will be nonzero (e.g., where the front volume pressure and the back volume pressure is not equal). Regardless of the initial deflection of the membrane 357, embodiments according to the teachings detailed herein and/or variations thereof reduce and/or eliminate the displacements of the diaphragm from its neutral position/deflection (whatever that may be) due to static pressure changes in the ambient environment. Indeed, some diaphragms 357 can have a natural memory that causes it to be bow shaped or the like even when pressures are equalized. Accordingly, embodiments detailed below will be described in terms of the membrane 357 relative to its neutral position, whether that be a zero deflection position or a nonzero deflection position.
As noted above, some embodiments are directed towards pressure equalization in a scenario where there is a combined front and back volume. In this regard, it is meant that there is fluid communication between the front and back volume. By way of example only and not by way of limitation, in an exemplary embodiment, the membrane 357 of the microphone can include one or more orifices (e.g., one or more piercings) that enables the flow of fluid from one side of the membrane 357 to the other side of the membrane 357, and thus from the front volume to the back volume, and vice versa. Accordingly, in an exemplary embodiment, the front volume and the back volume are not fluidically isolated from one another.
Unless otherwise explicitly stated herein, the teachings herein are applicable to embodiments where the front and back volumes are fluidically isolated from one another and embodiments where the front and back volumes are in fluid communication with one another (the latter being a combined front and back volume). Also unless otherwise stated herein, any phenomenon associated with the back volume as detailed herein can also corresponds to a phenomenon associated with the front volume, at least in embodiments where the front volume and back volume are in fluid communication with one another.
In this vein, most exemplary embodiments detailed herein are directed towards the embodiment where the front and back volumes are fluidically isolated from one another. However, it is noted that there is utilitarian value with respect to applying the teachings detailed herein to embodiments where the front and back volumes are in fluid communication with one another. In this regard, while the membrane 357 may not be deflected from the neutral position (or at least may not be significantly deflected from the neutral position) as a result of a difference in static pressure between the ambient environment and the combined front and back volumes, the diaphragms 334 may be deflected from their neutral positions. In this regard, it is noted that any teachings detailed herein associated with the membrane 357 can be applicable to the diaphragms 334. That is, for example, the diaphragms 334 can have neutral positions just as is the case with the membrane 357. In this regard, in scenarios where the static pressure of the ambient environment is greater than the static pressure within the front volume (and the static pressure within the combined front and back volumes in the case where there is fluid communication between the two volumes), the diaphragms 334 will be deflected inwards away from their neutral position. Conversely, in scenarios where the static pressure of the ambient environment is less than the static pressure within the front volume (and the static pressure within the combined front and back volumes in the case where there is fluid communication between the two volumes), the diaphragms 334 will be deflected outward away from their neutral position.
As noted above, an exemplary embodiment of the sensor assembly 350 utilizes device 410 to expand and/or contract the space constituting the back volume of the microphone 354. In an exemplary embodiment, the expansion and contraction is independent of movement of the membrane 357.
In an exemplary embodiment, the tube 501 is a micro tube. Additional features of this micro tube will be described below.
More specifically,
Accordingly, in an exemplary embodiment, sensor assembly 350 includes a back volume that includes a first volume 559A and a second volume 559B remote from and distinct from the first volume 559A in fluid communication with the first volume 559A. When
It is noted that the first volume 559A is located in a first housing/established by a first structure (housing 352 without the black box 510, where, instead, the black box 510 is replaced by a housing wall, as will be described in greater detail below) and the second volume is located in a second housing remote from the first housing, established by a second structure remote from the first structure and separable therefrom, where the second housing enables the expansion and contraction of the second volume.
Some exemplary features of the structures enabling the sensor assembly to have the functionality described above with respect to
As noted above, exemplary embodiments of the sensor assembly are such that the sensor assembly and a cochlear implant electrode array are part of a single unit. Accordingly, there is an exemplary embodiment that includes a sensor assembly including a compliant back cavity enclosure having the functionality as detailed herein and variations thereof integrated into a single unit (i.e., the electrode array assembly 390 is a combined electrode array 310 and the apparatus 320 including the compliant back cavity) with a cochlear implant electrode array. This is as differentiated from, for example, a sensor assembly according to the embodiment of
In view of the above, it is noted that embodiments based on the functional schematics of
Some more specific features of the embodiment of
Common to both
As will be detailed further below, adaptive volume structure 710 includes one or more diaphragms 711. The diaphragm(s) are configured to flex/stretch inward and/or outward, as functionally represented by arrow 799, thereby varying the size of the volume 759B. Accordingly, dashed arrow 799 corresponds to dashed arrow 599, and likewise represents the expandability and contractibility of the structure 710, and thus the volume 759B, and thus the back volume established by sub-volumes 759A, 759B and the volume of the inside of tube 501.
Some structural features of the adaptive volume structure 710 of
By way of example only and not by way of limitation, the diaphragms correspond to diaphragms manufactured via standard photolithography and dry etching processes. In at least some embodiments, the titanium diaphragms 711 are titanium foils. The titanium diaphragms have thickness of about 10 micrometers, although thicker and/or thinner diaphragms can be utilized (e.g., thicknesses of about 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, and/or about 20 μm or more or less or any value or range of values therebetween in about 1/10th micrometer increments (e.g., 8.3 micrometers, 12.1 micrometers, 6.6 micrometers to about 18 micrometers, etc.). In an exemplary embodiment, the titanium diaphragms are manufactured from thin wafers due to the fact that the titanium exhibits relatively high fracture toughness.
In an exemplary embodiment, the diaphragms 711 are corrugated diaphragms having a thickness of about 12 micrometers. In an alternate embodiment, the diaphragms are flat diaphragms having a thickness of about 10 micrometers
It is further noted that in at least some embodiments, the thicknesses of the diaphragms are relatively constant. That said, in an alternative embodiment, the thicknesses of the diaphragms vary with distance along the diameter. By way of example only and not by way of limitation, the thicknesses of the diaphragms located at or proximate to the rings can be thicker than the thicknesses of the diaphragms located away from the rings (i.e. the portions that flex). Indeed, in at least some embodiments, the rings can be dispensed with—the diaphragms being monolithic components with components that have the functionality of rings. Still further by way of example only and not by way of limitation, in at least some embodiments, the diaphragms can have raceways that are relatively thin relative to the remainder of the diaphragms. That is, in an exemplary embodiment, the diaphragms can have path(s) that circumnavigate a geometric center of the diaphragms of relative thinness located on the outer locations of the diaphragm but inboard of the rings. It is these locations that provide most of the flexure, or at least the greatest local degree of flexure, with the remainder of the diaphragms being relatively inflexible.
Referring to
Any configuration of the diaphragm-ring assembly that can enable the teachings detailed herein and are variations thereof to be practiced can utilize in at least some embodiments.
As can be seen, tube 501 extends through one side of the ring 720 into the interior volume 759B, thus placing that volume into fluid communication with volume 759A of the housing 752. While tube 501 is depicted as passing through the ring 720, the tube can instead stop short of the extension into the volume 759B depicted in
Thus, adaptive volume structure 710 includes a stack of clamped diaphragms 711, wherein the diaphragms 711 are configured to deflect in first directions and second directions (inward into volume 759B and outward away from volume 759B), thereby respectively contracting and expanding the back volume (volume 759A plus volume 759B plus the volume of the inside of the tube 501) independent of the movement of the membrane 357.
Still with reference to
Thus, as can be seen from
In an exemplary embodiment, the adaptive volume structure 710 is implanted in the recipient beneath the outer layer of the skin of the recipient at a location such that the diaphragm(s) 711 are deflected dependent on a difference between the ambient pressure relative to the location of the receptor 330 and the internal pressure (back volume and/or combined front and back volume), thereby modifying the size of the back volume of the microphone and returning and/or maintaining the membrane 357 at a neutral position (and/or the diaphragm(s) 334 at the neutral position). In at least some exemplary embodiments, the adaptive volume structure 710 is located above the mastoid bone of the recipient (e.g., behind and/or above the ear canal of the recipient). In an exemplary embodiment, it is configured to be located between the outer surface of the mastoid bone and the skin of recipients.
Accordingly, in an exemplary embodiment, diaphragm(s) numeral 711 are exposed to the ambient environment, and thus the ambient pressure at a location between the mastoid bone and the outer surface of the skin of the recipient. Thus, pressure changes in the ambient environment will cause the diaphragm(s) 711 to defect, thereby varying the volume 759B, and thus equalizing the pressure between the front volume and the back volume (or between the ambient environment and the combined front and back volume), because the pressure of the ambient environment proximate the surface(s) of the diaphragm(s) 711 will be substantially about the same as the pressure of the environment within the cochlea where receptor 330 is located (which influences the pressure of the front volume). Thus, the deflection of the diaphragm(s) 711 will vary the interior volume 759B, and thus equalize the pressures between the back volume and the front volume of the microphone of the sensor 350 (and/or between the combined front and back volume and the ambient environment).
As noted above, embodiments of the adaptive volume structure 710 can use one or two diaphragms. Embodiments that utilize one diaphragm where instead of two diaphragms, one rigid plate 712 is utilized in place of the diaphragm can have utilitarian value where the flexation/stretching of that one diaphragm 711 is sufficient to enable the teachings detailed herein and/or variations thereof, such as to equalize the pressures between the front and back volume and/or between the total combined volume and the ambient environment, where the rigid plate 712 provides protection to the adaptive volume structure.
In an exemplary embodiment, the back volume of the sensor 750 (the volume “to the left” of membrane 357—volume 759A, volume 759B and the internal volume of tube 501), which is a variable volume owing to the diaphragm(s) 710, is significantly larger than the front volume (volume “to the right” of membrane 357—the internal volume of the receptor 330, the internal volume of tube 340 and the portion of the sensor 350 inside housing 752 not including portion 359 (with reference to
At least some embodiments utilize a plurality of volumes 759B that are manifolded together, and thus pneumatically interconnected. In this regard,
Fluid communication between the ambient environment and volume 791 is utilitarian for embodiments where four diaphragms 711 are utilized. In this regard, the ambient pressure is exposed not only to the diaphragms 711 on the outside of the adaptive volume structure 810 (i.e., the top and bottom diaphragms), but also to the diaphragms located in the middle of the adaptive volume structure 810. That said, in an alternative embodiment, where rigid plates alike are utilized for the middle components, it may not be necessary to have fluid communication between volume 791 and the ambient environment. Indeed, in such embodiments, volume 791 may not exist. Instead, the rigid plates can be located back to back without a volume therebetween, or, in an alternative embodiment, a single rigid plate can be utilized; one side of the plate establishing one of the volumes 759B and the other side of the plate establishing the other of the volumes 759B—both of the volumes 759B being variable volumes owing to the fact that each is bounded by a diaphragm 711 that has a surface exposed to the ambient environment. Further, in alternate embodiments, the rigid plates can be located on the outside surfaces of the adaptive volume structure 810. That is, flexible diaphragms can be utilized for the middle to diaphragms, which will be exposed to the ambient pressures via tube 803, and thus will flex with pressure changes, thus causing the volumes 759B to vary.
As noted above, volumes 759B are manifolded together. As can be seen in
It is again reiterated that the
Any device, system, and/or method that can place the pertinent volumes into fluid communication with one another to enable the teachings detailed herein and/or variations thereof can be utilized in at least some embodiments.
In view of
It is noted that as with the embodiments of
It is noted that alternatively and/or in addition to the rings 821, the caps 930 can be configured such that they have hollow portions therein that provide a space to establish volumes 991. By way of example only and not by way of limitation, in at least some embodiments, rings 821 can be monolithic components with caps 930. Indeed, in an exemplary manufacturing process, cap 930 is machined to place a circular hollow portion therein to provide for the volume 991 when a diaphragm 711 is attached to cap 930.
Also, while vertical and horizontal bores have been referenced above, where it has been implied that the directions of the bores are linear, curved bores can be utilized as well. By way of example only and not by way of limitation, in at least some embodiments, curved conduits can be machined or otherwise formed into the upper and/or lower portions of the rings and/or the rings can be bifurcated, at least partially, into outer rings and inner rings, where fluid conduits are located between the outer rings and inner rings. Such can be achieved via manufacturing processes where each ring and each diaphragm and each cap is a separate component that is ultimately stacked up and connected to each other during assembly, where there is easy access to any side of any individual component prior to assembly. Again, any device, system and/or method that can enable fluid communication between the various volumes and/or the ambient environment can be utilized in at least some embodiments.
In view of the above, it is now noted that an exemplary embodiment includes an implantable static pressure equalization system configured to equalize an internal pressure of an apparatus, such as the sensor assembly 350, that is configured to sense a dynamic phenomenon in a recipient (e.g., such energy travelling through the fluid of the cochlea resulting from ambient sound) with a static pressure of an ambient environment. As can be seen from
Further, still with reference to
In an exemplary embodiment, silicone housing encompasses the stack of the diaphragms, the caps and the spacer (e.g., adaptive volume structure 910). More specifically, with reference to
Briefly noted above is the concept of a “filter” to prevent or otherwise limit tissue ingress into volumes 791 and/or 991, which are in fluid communication with the ambient environment via tubes 803 (or whatever other mechanism is used for fluid communication). Along these lines, silicone housing 1050 forms an open volume 1040 which is generally donut shaped that circumnavigates the outer periphery of the adaptive volume structure 1010, although in alternate embodiments, it need not circumnavigate the adaptive volume structure 1010—any configuration or extension of the volume that can enable the teachings detailed herein that are variations thereof to be practiced can be utilized in at least some embodiments. This open volume is in fluid communication with the volumes 791 and 991. Accordingly, in this exemplary embodiment, volume 1040 is an integral part of the silicone structure which houses the adaptive volume structure 1010 and forms another adaptive volume. In this regard, pressure changes in the ambient environment in which the assembly 1020 is located (e.g., the environment between the mastoid bone and the surface of the skin of the recipient, etc.) results in expansion or contraction of the size of the volume 1040, thereby at least effectively equalizing the pressure of the volume 1040 with the ambient environment. Because the volumes 791 and 991 are in fluid communication with the volume 1040, pressure changes in the volume 1040 are communicated to the volumes 791 and 991. These pressure changes in turn result in deflections of the diaphragms as detailed above, and thus changes in the volumes 759B as detailed above.
In an exemplary embodiment, by way of example only and not by way of limitation, the silicone of the housing 1050 is relatively highly elastic, and the structure of the housing 1050 is such that the portions of the housing that create the volume 1040 results in a sufficiently elastic structure that enables the volume 1040 to be an adaptive volume, in a manner concomitant with the adaptive volume of the back volume of the microphone of sensor 350. In this regard, an exemplary embodiments includes a sensor according to any of the sensors detailed herein having a microphone having a first back volume and a second back volume, where the first back volume is fluidically isolated from the second back volume. In an exemplary embodiment, both the first back volume and the second back volume are adaptive back volumes. In the embodiment of
In an exemplary embodiment, the silicone of the housing 1050 provides protection against contamination of volumes 791 and 991 with human tissue. That is, volume 1040 is not a hermetically sealed volume, and thus volumes 791 and 991 are likewise not hermetically sealed volumes.
As noted above, embodiments of the sensor 750 are configured to sense a physical phenomenon within the cochlea of a recipient, and the adaptive volume structures associated therewith are configured to be located between the mastoid bone and the outer surface of the skin in back of and/or above the ear canal of the recipient. Accordingly, in an exemplary embodiment, the tube 501 is configured to extend from the housing 752 of the sensor 750, which is located proximate to the cochlea as can be seen in
More specifically,
From the receiver stimulator 11180 there extends an elongate stimulating assembly 11118 corresponding to the elongate stimulating assembly 118 detailed above which includes electrode array assembly 390. The elongate stimulating assembly 11118 includes and/or runs parallel to tube 501 (in an exemplary embodiment, the tube 501 is integral with the other components of the elongate stimulating assembly 118). In an exemplary embodiment, the tube 501 is integrated into the structure of the stimulator of the internal component. In an exemplary embodiment, the tube 501 can run directly through the stimulator or run around the periphery (side, above, etc.) of the stimulator component to reach the adaptive volume structure 1010. In an exemplary embodiment, the tube 501 can connect to a component of the stimulator, and thus the stimulator can place the microphone into fluid communication with the adaptive volumes of the adaptive volume structure 1010 (another tube or some other component can place the adaptive volume structure 1010 into fluid communication with the stimulator). In an exemplary embodiment, electrical leads extending between the elongate stimulating assembly 390 and the receiver-stimulator 11180 are located in the tube 501 (i.e., inside the conduit established by tube 501).
Consistent with other internal components of cochlear implants, the receiver stimulator 11180 is encapsulated in silicone. Accordingly, the adaptive volume structure 1010 is also encapsulated in silicone. In an exemplary embodiment, the encapsulation is such that an adaptive volume corresponding to volume 1040 is present therein. Indeed, in an exemplary embodiment, the receiver stimulator 11180 corresponds to a combination of assembly 1020 of
Also consistent with other internal components of cochlear implants, the elongate stimulating assembly 118 is also encapsulated in silicone, at least to the point of the electrodes thereof. With respect to the latter, the tube 501 and the leads extending from the electrode array assembly 390 can be encapsulated in the same silicone.
It is noted that in this exemplary embodiment, electrode array assembly 390 utilizes the sensor assembly 750 detailed above.
As can be seen from
Accordingly, from the above, it can be seen that in an exemplary embodiment, the adaptive volume structure 1010 comprises a stack of diaphragms 711, caps 930, spacers 720, 721 and 821 and a ferromagnetic component 1060, such as a permanent magnet, along with a receiver coil 11136 of a transcutaneous electromagnetic communication system, all of which are encompassed in a silicone housing 1050. Further, from the above, it can be seen that an exemplary embodiment includes a cochlear implant including a receiver-stimulator component, a cochlear implant electrode array 390 including a microphone configured to be located proximate to and/or in the cochlea of the recipient, and an adaptive volume structure according to any of the embodiments detailed herein and/or variations thereof, wherein a volume of the back volume extends from the electrode array of the cochlear implant to the receiver-stimulator component 11180.
As noted above,
Like reference numbers of
Adaptive volume structure 1211 is constructed utilizing a material that moves in a manner analogous to an accordion. By way of example only and not by way of limitation, the walls of the adaptive volume structure 1211 are constructed of flexibly corrugated sheet(s) that enable the back wall 1212 to move in the direction of arrow 1299, thereby varying the size of the volume 1259. Accordingly, dashed arrow 1299 corresponds to dashed arrow 699, and likewise represents the expandability and contractibility of the structure 1211 and thus the volume 1259 (the back volume). As with the diaphragms of the embodiments of
Alternatively and/or in addition to this, the adaptive volume structure 1211 can be configured of material that expands and/or contracts in a radial direction relative to the longitudinal axis of the housing 1252 with a change in ambient pressure outside the adaptive volume 1259. By way of example only and not by way of limitation, the walls 1211 can be extensions of the walls of housing 1252, where the walls collapse inward and/or expand outward toward/away from the longitudinal axis with pressure changes to equalize the pressure inside the adaptive volume 1259 with the pressure outside the adaptive volume 1259 (which can be the pressure of the ambient environment in embodiments where the adaptive volume 1259 encompasses both the front and back volumes (the combined front and back volumes)).
In an exemplary embodiment, the adaptive volume structure 1211 can be a balloon-type structure having a material that stretches and contracts with changing pressure. In this regard, in an exemplary embodiment, the adaptive volume structure 1211 can have a functionality analogous to a balloon that is “blown up” at sea level to perhaps one-quarter capacity, and then taken to a higher elevation, where the balloon expands, thereby increasing the size of the internal volume of the balloon, but equalizing the pressure inside the balloon with the ambient pressure.
In an exemplary embodiment, structural components can be utilized to limit the expansion and/or contraction of an adaptive volume structure 1211. By way of example through analogy only and not by way of limitation, in an exemplary embodiment, such a structure can limit the expansion of the balloon-like embodiment so that regardless of the pressure decrease, the balloon will only expand to a given volume, thereby preventing the balloon from bursting or the like or otherwise taking up too much room within the middle ear of the recipient.
In an exemplary embodiment, the adaptive volume structure is configured to both expand and/or contract in the axial direction and the radial direction of the longitudinal axis of the housing 1259 to vary the volume 1259 of the sensor 1250.
With continued reference to the embodiment of
In an exemplary embodiment, the structure of 1211 is titanium (including a titanium alloy). Any material that can be sufficiently flexible but also have a sufficient duty cycle to provide long-term implantation of a prosthesis including the sensor 1250 of
In an exemplary embodiment, the structure 1211 is substantially rotationally symmetric about the longitudinal axis thereof (and as is the case with some embodiments of the adaptive volume structures 711, 811, 911 and 1011 and assembly 1020 detailed above) and/or the longitudinal axis of the housing 1252 (as can be the case with housing 1252.) Accordingly, in an exemplary embodiment, the structure 1211 has a circular cross-section lying on a plane normal to the longitudinal axis (as is the case with housing 1252). That said, in an alternate embodiment, the structure 1211 can have a rectangular (e.g., square) cross-section (as is the case with some embodiments of the adaptive volume structures 711, 811, 911 and 1011 and assembly 1020 detailed above). Any configuration of the structure 1211 that can enable the teachings detailed herein and are variations thereof to be practiced can be utilized in at least some embodiments.
Further, it is noted that while the embodiment of
In an exemplary embodiment, the back volume of the sensor 1250 (the volume “to the left” of membrane 357-1211) can be smaller, about the same size, or larger (including substantially larger) than that of the front volume (volume “to the right” of membrane 357 the internal volume of the receptor 330, the internal volume of tube 340 and the portion of the sensor 1250 inside housing 1252 not including portion 359 (with reference to FIG. 3)), when the static pressures in the two volumes are equalized at an initial pressurization (e.g., 0.8 bars). In an exemplary embodiment, the size of the back volume is about ½, ⅔rds, the same as, two times, three times, four times, five times or more the size of the front volume when the static pressures are equalized at an initial pressurization (e.g., 0.8 bars). Any ratio of volumes of the back volume, which is a variable volume, to the front volume, which is a constant volume (or at least an effectively constant volume in that the movement of the diaphragm is negligible relative to changing the volume of the front volume) that can enable the teachings detailed herein and/or variations thereof to be practiced can be utilized in at least some embodiments.
In an alternate embodiment, the adaptive volume structure 1311 can be configured as a piston to move to the left and to the right inside the housing 1252. Again, as with the embodiment of
It is noted that like functionalities of the embodiment of
As can be seen from the embodiments of
As noted above, in at least some embodiments, tube 501 extends from a location proximate the cochlea to a location behind and/or above the ear canal of the recipient between the mastoid bone and the outer skin of the recipient. Owing to the fact that the tube 501 must at least somewhat conform to the relevant topography of the recipient (e.g., must curve about the skull, etc.), the tube is configured to be sufficiently flexible to enable application in the recipient in accordance therewith. In an exemplary embodiment, the tube 501 extends a distance of 90 mm or thereabouts. An exemplary embodiment of the tube 501 having utilitarian value with respect to the other embodiments detailed herein and are variations thereof will now be detailed.
In an exemplary embodiment, tube 501 is a micro tube made entirely of a titanium alloy, and is embedded in a silicone shell. That said, in an alternative embodiment, the tube can be made out of other metallic materials, such as gold. In an exemplary embodiment, the tube has sufficiently high mechanical compliance to be compatible with insertion of the stimulating assembly into a cochlea during a surgical operation, as the tube 501 extends from the stimulating assembly to the receiver-stimulator of the cochlear implant in at least some embodiments. In an exemplary embodiment, the micro tube has an outer diameter of about 0.5 mm, and an interior diameter of about 0.3 mm. Any geometry that can enable the teachings detailed herein and/or variations thereof can utilize in at least some embodiments.
Also as can be seen in
Still with reference to
That said, in at least some embodiments, the spiraling of the leads 1580 can provide utilitarian value with respect to reducing EMI induced into lead 15399 relative to that which be the case if the leads 1580 were run parallel to the micro tube 15501.
It is noted that as with other elements of the components detailed herein, both the micro tube 15501 and the leads 1580 can be embedded in elastic (e.g., highly elastic) silicone adhesive and/or other biocompatible materials.
It is noted that in alternate embodiments, other transmission devices can utilize to communicate between the microphone 354 and the receiver stimulator. By way of example only and not by way of limitation, fiber optics can be utilized. Still, in such instances, utilizing the conduit 1572 can have utilitarian value with respect to the armored features afforded thereby.
Is further noted that routing of the leads 15399 through the conduit 1572 can have utilitarian value with respect to “feeding through” the leads 15399 into the receiver stimulator. Because the interface between the receiver stimulator and the micro tube is established by these two components, the leads 15399 simply pass through into the receiver stimulator from the micro tube without the need for an individual feed through. This is also the case with respect to “feeding through” the leads 153999 into the housing 752. Because the interface between the housing 752 in the micro tube is established by these two components (a hermetic seal is already established by these two components), the leads 15399 simply pass through into the housing from the micro tube, again without the need for an individual feed through. This can have utilitarian value with respect to the fact that the housing 752 is relatively smaller than the receiver stimulator.
In an exemplary embodiment, the heights and/or the widths and/or the spacing between the individual corrugations is set to control the radius that is the demarcation between that which the micro tube can be more easily and less easily flexed. By way of example only and not by way of limitation, all other facets being equal, corrugations that are located further from one another will result in a higher limit bending radius than corrugations that are located closer to one another, corrugations having a high height will result in a lower limit bending radius relative to tubes that have corrugations having a lower height, corrugations having a longer length will result in a lower limit bending radius relative to telling corrugations having a lower length.
Some exemplary methods according to some exemplary embodiments will now be described.
An exemplary embodiment includes an exemplary method of adapting internal pressure of a first volume of an implanted medical device to a pressure of an ambient environment (e.g., the pressure inside the cochlea) by automatically adjusting a size of a second volume separate from the first volume. In an exemplary embodiment, this method is executed utilizing the sensor 750 detailed above, where the first volume is the volume inside housing 752, and the second volume is the volume (the hermetic volume) of adaptive volume structure 710, 810, 910 or 1010 detailed above. By “automatically,” it is meant that the size of the second volume is adjusted without human intervention.
With respect to the aforementioned exemplary method when implemented in the cochlear implant according to
In another exemplary embodiment, there is an exemplary method executed utilizing any of sensors 750, 1250 and/or 1350, that entails automatically (i.e., without human intervention) maintaining a neutral position of a membrane (e.g., membrane 357) of an implanted microphone (e.g., microphone 354). The method is executed in a device where the membrane separates a front volume from a back volume of the implanted microphone, where the front volume and back volume are fluidically isolated from one another. The method is executed when a pressure of the ambient environment in which the microphone is located changes. The method is executed by automatically adjusting the size in the back volume to at least substantially equalize the pressure in the back volume with the pressure in the front volume (which has changed due to the change in pressure of the ambient environment) and/or to at least substantially equalize the pressure in the combined front and back volume with the pressure of the ambient environment.
In an exemplary embodiment, the device in which the aforementioned method is executed is such that the front volume and the back volume are hermetically isolated volumes relative to the ambient environment of the implanted microphone. Consistent with sensors 750, 1250 and 1350 that have a receptor 330 located in the cochlea, the front volume is a volume that extends at least partially into a cochlea of the recipient, and the back volume is a volume that extends at least partially in an extra-cochlear environment of the recipient.
In an exemplary embodiment executed in a cochlear implant according to
In an exemplary embodiment, the first location is a location of the primary internal coil of the cochlear implant. The method further includes at least one of expanding or contracting the back volume at a location at least one of at or proximate the first location. In an exemplary embodiment, this can be accomplished utilizing adaptive volume structures that are located in the receiver-stimulator of the cochlear implant proximate to the primary internal coil, as detailed above with respect to the embodiment of
Some exemplary performance features of the adaptive volume structures detailed herein and/or variations thereof will now be described.
In at least some embodiments, the adaptive volume structures detailed herein are configured to maintain the membrane 357 at a location where the sensitivity of the microphone 354 is relatively constant. By way of example only and not by way of limitation, such locations are deflections of the membrane 357 that are smaller than the membrane thickness (e.g., about 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% and/or 10% of the membrane thickness or any value or range of values therebetween in about 1% increments). More specifically, when the membrane is deflected away from the neutral position a significant amount, the response of the microphone 354 becomes non-linear and a relatively significant decrease in the sensing performance of the microphone 354 can occur. Accordingly, exemplary embodiments utilizing the adaptive volume structures detailed herein and variations thereof are configured to limit deflection of the membrane 357 and/or diaphragm(s) 334 due to changes in ambient pressure to deflections where the microphone response still remains substantially linear (including linear), and the sensing performance of the microphone 354 due to pressure changes is effectively maintained/not degraded.
At least some embodiments according the teachings detailed herein and are variations thereof are configured to achieve the above noted performance characteristics for changes in ambient pressure ranges ranging from 0.7 bars to 1.2 bars. Accordingly, by way of example only and not by way of limitation, in at least some embodiments, an acoustic sensitivity of an inner ear sensor such as the sensor 750, 1250 or 1350 detailed above and or variations thereof will remain effectively constant/substantially constant (including constant) within a pressure range of about 0.6 bars to about 1.3 bars, about 0.7 bars to about 1.2 bars, about 0.8 bars to about 1.1 bars, about 0.9 bars to about 1.0 bars, or within a range from about 0.6 bars to about 1.2 bars or any range therein in about 0.01 bar increments.
It is noted that different configurations of diaphragms can have different utilitarian value depending on a given scenario. By way of example only and not by way of limitation, a corrugated diaphragm having a thickness of about 12 μm can provide better pressure equalization performance at higher ambient pressure deviations from the initial internal pressure (e.g., 0.8 bars) than a flat diaphragm having a thickness of about 10 μm, all other things being equal. Conversely, a flat diaphragm having a thickness of about 10 μm can provide better pressure equalization at small deviations. Such phenomenon can be seen from
As is noted in the graphs, embodiments can utilize flat diaphragms or corrugated diaphragms. In an exemplary embodiment, there is an adaptive volume structure according to any as detailed herein and/or variations thereof that utilizes a combination of flat and corrugated diaphragms. By way of example only and not by way limitation, with reference to the stack of
The behavior of the various embodiments variously utilizing corrugated diaphragms and flat diaphragms reflects the stiffness characteristics of a corrugated diaphragm with an increasing diaphragm deflection. This can be because the corrugated diaphragm is stiffer than the flat diaphragm for small deflections. However, because of the larger linear operating ranges the corrugated diaphragm is more compliant at higher deflections. Accordingly, in an exemplary embodiment in which the sensors are expected to be utilized over a wide range of ambient pressures (e.g. 0.6 bars to 1.2 bars), the adaptive volume structures utilized in the sensors detailed herein and are variations thereof utilize corrugated diaphragms having thickness of 12 micrometers resulting in a pressure load it is reduced by approximately a factor of four relative to that which would be the case utilizing flat diaphragms having a thickness of 10 micrometers, all other things being equal.
As can be seen from the graph of
In this regard, it is noted that exemplary static pressure equalization systems can include any number of combinations of adaptive volume structures. These can be arranged in a stack as presented in the embodiments of
It is noted that the embodiments represented by
As noted above, some and/or all of the teachings detailed herein can be used with a hearing prosthesis, such as a cochlear implant. That said, while the embodiments detailed herein have been directed towards cochlear implants, other embodiments can be directed towards application in other types of hearing prostheses, such as by way of example, bone conduction devices (e.g., active and/or passive bone conduction devices, percutaneous bone conduction devices, etc.), direct acoustic cochlear implants, etc. Indeed, embodiments can be utilized with any type of hearing prosthesis that utilizes an implanted microphone, irrespective of where the implanted microphone is located.
Further, while embodiments detailed herein are directed towards sensors used for cochlear implants/used for intra-cochlear implementations, other embodiments can be utilized for other types of the implantable devices having volumes that are hermetically sealed, such as by way of example only and not by way of limitation, intracranial implementations intraocular implementations and/or any other intra-body dynamic pressure measurement sensors to which the teachings detailed herein and are variations thereof can be applicable.
It is noted that any disclosure with respect to one or more embodiments detailed herein can be practiced in combination with any other disclosure with respect to one or more other embodiments detailed herein.
It is noted that some embodiments include a method of utilizing a prosthesis including one or more or all of the teachings detailed herein and/or variations thereof. In this regard, it is noted that any disclosure of a device and/or system herein also corresponds to a disclosure of utilizing the device and/or system detailed herein, at least in a manner to exploit the functionality thereof. Further, it is noted that any disclosure of a method of manufacturing corresponds to a disclosure of a device and/or system resulting from that method of manufacturing. It is also noted that any disclosure of a device and/or system herein corresponds to a disclosure of manufacturing that device and/or system.
While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
This application claims priority to Provisional U.S. Patent Application No. 62/013,829, entitled INTERNAL PRESSURE MANAGEMENT SYSTEM, filed on Jun. 18, 2014, naming Joris WALRAEVENS of Mechelen, Belgium, as an inventor, the entire contents of that application being incorporated herein by reference in its entirety.
Number | Date | Country | |
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62013829 | Jun 2014 | US |