Electrical potential monitoring of a medical device recipient

Abstract

Presented herein are techniques for evaluating the characteristics of a body chamber of a recipient of a medical device (medical device recipient). More specifically, in accordance with embodiments presented herein, a system delivers one or more current pulses to a body chamber (e.g., cochlea) to generate an electrical potential at a first location in the body chamber. In addition, the system induces motion / vibration of fluid in the body chamber and contemporaneously measures / monitors the electrical potential at the first location in the body chamber. The system then uses the measured electrical potential to evaluate one or more characteristics of the body chamber.

Description

Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIELECTRICAL POTENTIAL MONITORING OF A MEDICAL DEVICE RECIPIENT BACKGROUNDTechnical Field[oooi] The present disclosure relates generally to the use of electrical potential measurements to evaluate characteristics of a body chamber of a medical device recipient.Related Art

[0002] Medical devices are devices that are intended to be used for medical purposes. They can vary in both their intended use and indications for use. Examples range from simple, low-risk medical supplies to complex, potentially high-risk devices that are implanted and / or sustain life, such as deep brain stimulators and brain-computer interfaces. Other categories of medical device include diagnostic equipment.

[0003] Hearing devices act on an actual or potential auditory perception of an individual, including to improve perception of sound signals, to reduce perception of sound signals, etc. In particular, a hearing device can deliver sound signals to a user in any form, including in the form of acoustical stimulation, mechanical stimulation, electrical stimulation, etc., and / or can operate to suppress all or some sound signals. As such, a hearing device can be a device for use by a hearing-impaired person (e.g., hearing aids, middle ear auditory prostheses, bone conduction devices, direct acoustic stimulators, electro-acoustic hearing prostheses, auditory brainstem stimulators, bimodal hearing prostheses, bilateral hearing prostheses, dedicated tinnitus therapy devices, tinnitus therapy devices, etc.) or a device for use by a person with normal hearing (e.g., a consumer device that provides audio streaming, a consumer headphone, an earphone, etc.), a hearing protection device (e.g., a noise cancellation headset, a loudness reduction apparatus, etc.), etc.SUMMARY

[0004] In one aspect, a method is provided. The method comprises: generating an electrical potential at a first location in recipient; delivering one or more acoustic signals to vibrate body fluid at the first location; contemporaneously with delivery of the one or more acoustic signals, measuring the electrical potential at the first location; and evaluating acoustic transmission characteristics of at least the first location based on the measured electrical potential at the first location.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0005] In another aspect, a system is provided. The system comprises: a stimulating assembly configured to be implanted in a recipient and to generate an electrical potential at a location of a cochlea of the recipient; an acoustic source configured to deliver an acoustic signal to vibrate the cochlea; and a processor configured to monitor the electrical potential at the location following delivery of the acoustic signal to the cochlea.

[0006] In yet another aspect, a method is provided. The method comprises: generating an electrical potential within fluid of a body chamber of a recipient; delivering an input signal to vibrate the fluid in the body chamber; monitoring the electrical potential responsive to delivery of the input signal; and determining one or more characteristics of the body chamber based on the electrical potential.

[0007] In yet another aspect, one or more non-transitory computer readable storage media are provided. The one or more non-transitory computer readable storage media comprise instructions that, when executed by one or more processors, cause the one or more processors to: generate an electrical potential within fluid of a body chamber of a recipient, wherein the electrical potential is generated at a first location on the body chamber; vibrate the fluid in the body chamber; contemporaneously with vibration of the fluid, monitor the electrical potential at the first location; and determine or more characteristics of the body chamber based on the monitoring of the electrical potential.

[0008] In yet another aspect, a system is provided. The system comprises: one or more electrodes configured to generate electrical potential at a location of a body chamber of the recipient; an acoustic source configured to deliver one or more acoustic signals to vibrate fluid in the body chamber; at least one electrode disposed proximate to the location; at least one amplifier circuit configured to capture electrical potential measurements via the at least one electrode; and a processor configured to use the electrical potential measurements to monitor the electrical potential at the location, and to determine at least one characteristic of the body chamber based on the monitoring of the electrical potential.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIBRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments of the present disclosure are described herein in conjunction with the accompanying drawings, in which:[ooio] FIG. 1A is a schematic diagram illustrating a cochlear implant system configured to implement aspects of the techniques presented herein;[ooii] FIG. IB is a side view of a recipient wearing a sound processing unit of the cochlear implant system of FIG. 1A;

[0012] FIG. 1C is a schematic view of components of the cochlear implant system of FIG. 1 A;

[0013] FIG. ID is a block diagram of the cochlear implant system of FIG. 1 A;

[0014] FIG. IE is a schematic diagram illustrating a portion of the stimulating assembly of the cochlear implant system of FIG. 1 A;

[0015] FIG. 2A is a schematic view of a system to measure electric potential of a cochlea of a recipient, in accordance with embodiments presented herein;

[0016] FIG. 2B is a schematic view of a portion of the system of FIG. 2A;

[0017] FIGs. 2C and 2D are schematic front and side views, respectively, of a recipient wearing a master hearing aid in a clinical setting, in accordance with embodiments presented herein;

[0018] FIG. 3A is a schematic view illustrating an electrical potential generated in a cochlea, in accordance with embodiments presented herein;

[0019] FIG. 3B is a schematic view illustrating another electrical potential generated in a cochlea, in accordance with embodiments presented herein;

[0020] FIG. 4 graphically illustrates measurements of various parameters while performing techniques presented herein;

[0021] FIGs. 5A, 5B, 6, 7, and 8 are flowcharts of methods for evaluating characteristics of a cochlea based on electrical potential, in accordance with embodiments presented herein;

[0022] FIG. 9 is a schematic view of a vestibular stimulator system with which aspects of the techniques presented herein can be implemented; and

[0023] FIG. 10 is a schematic diagram illustrating a computing device that can perform techniques presented herein.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIDETAILED DESCRIPTION

[0024] Presented herein are techniques for evaluating, determining, analyzing (sometimes collectively referred to herein as “evaluating”) the characteristics of a location (e.g., in a fluid-filled body chamber) of a recipient of a medical device (medical device recipient). More specifically, in accordance with embodiments presented herein, a system delivers one or more current pulses to a body chamber (e.g., cochlea), to generate an electrical potential at a first location in the body chamber. In addition, the system induces motion / vibration of fluid in the body chamber and contemporaneously measures / monitors the electrical potential at the first location in the body chamber. The system then uses the measured electrical potential to evaluate, determine, or otherwise analyze one or more characteristics of the body chamber.

[0025] In certain examples, the steps of generating an electrical potential, inducing motion of the fluid in the body chamber, and the measurement of electrical potential are repeated at a plurality of locations in the body chamber. In such examples, the system then uses the electrical potential measured at the plurality of locations to evaluate the one or more characteristics of the body chamber.

[0026] There are a number of different types of device in / with which the techniques presented herein can be implemented. Merely for ease of description, the techniques presented herein are primarily described with reference to a specific device. However, it is to be appreciated that the techniques presented herein can also be partially or fully implemented by any of a number of different types of devices or systems, including consumer electronic devices (e.g., consumer hearing devices, consumer computing devices such as mobile phones and tablets, audio equipment such as home theatre and car audio systems, etc.), computing systems (e.g., servers in data centers, Intemet-of-Things (loT) devices), various types of software systems, such as databases, machine learning and artificial intelligence systems, other medical devices, such as diagnostic equipment or life sustaining equipment, etc. For example, the techniques presented herein could be used in or with sensory protheses, including hearing aids and cochlear implants, and various medical devices, such as pacemakers, drug delivery systems, implantable defibrillators, functional electrical stimulation devices, sleep disorder devices (e.g., sleep apnea devices), seizure devices (e.g., devices for monitoring and / or treating epileptic events), balance or movement disorder devices (e.g., vestibular stimulation devices), tinnitus management devices, visual implants (e.g., bionic eyes), and other neuromodulation devices (e.g., brain-computer interfaces).Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0027] FIGs. 1 A-1D illustrate an example cochlear implant system 102 with which aspects of the techniques presented herein can be implemented. The cochlear implant system 102 comprises an external component 104 that is configured to be directly or indirectly attached to the body of the user, and an internal / implantable component 112 that is configured to be implanted in or worn on the head of the user. In the examples of FIGs. 1 A-1D, the implantable component 112 is sometimes referred to as a “cochlear implant.” FIG. 1A illustrates the cochlear implant 112 implanted in the head 154 of a user, while FIG. IB is a schematic drawing of the external component 104 worn on the head 154 of the user. FIG. 1C is another schematic view of the cochlear implant system 102, while FIG. ID illustrates further details of the cochlear implant system 102. For ease of description, FIGs. 1 A-1D will generally be described together.

[0028] In the examples of FIGs. 1A-1D, the external component 104 comprises a sound processing unit 106, an external coil 108, and generally, a magnet fixed relative to the external coil 108. The cochlear implant 112 includes an implantable coil 114, an implant body 134, and an elongate stimulating assembly 116 configured to be implanted in the user’s cochlea. In one example, the sound processing unit 106 is an off-the-ear (OTE) sound processing unit, sometimes referred to herein as an OTE component, that is configured to send data and power to the cochlear implant 112. In general, an OTE sound processing unit is a component having a generally cylindrically shaped housing 111 and which is configured to be magnetically coupled to the user’s head 154 (e.g., includes an integrated external magnet 150 configured to be magnetically coupled to an internal / implantable magnet 152 in the cochlear implant 112). The OTE sound processing unit 106 also includes an integrated external (headpiece) coil 108 (the external coil 108) that is configured to be inductively coupled to the implantable coil 114.

[0029] It is to be appreciated that the OTE sound processing unit 106 is merely illustrative of the external devices that could operate with cochlear implant 112. For example, in alternative examples, the external component 104 can comprise a behind-the-ear (BTE) sound processing unit configured to be attached to, and worn adjacent to, the recipient’s ear. A BTE sound processing unit comprises a housing that is shaped to be worn on the outer ear of the user. In certain examples, the BTE is connected to a separate external coil assembly via a cable, where the external coil assembly is configured to be magnetically and inductively coupled to the implantable coil 114, while in other embodiments the BTE includes a coil disposed in or on the housing worn on the outer ear of the user. It is also to be appreciated that alternative external components could be located in the user’s ear canal, worn on the body, etc. ForAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIexample, the external component could be a micro-BTE unit, an in-the-ear (ITE) unit, etc. In addition, as described elsewhere herein, the techniques could be implemented without an external component (e.g., in a totally-implantable arrangement, a mostly-implantable arrangement, etc.).

[0030] Although the cochlear implant system 102 includes the sound processing unit 106 and the cochlear implant 112, as described below, the cochlear implant 112 can operate independently from the sound processing unit 106, for at least a period, to stimulate the user. For example, the cochlear implant 112 can operate in a first general mode, sometimes referred to as an “external hearing mode,” in which the sound processing unit 106 captures sound signals which are then used as the basis for delivering stimulation signals to the user. The cochlear implant 112 can also operate in a second general mode, sometimes referred as an “invisible hearing” mode, in which the sound processing unit 106 is unable to provide sound signals to the cochlear implant 112 (e.g., the sound processing unit 106 is not present, the sound processing unit 106 is powered-off, the sound processing unit 106 is malfunctioning, etc.). As such, in the invisible hearing mode, the cochlear implant 112 captures sound signals itself via implantable sound sensors and then uses those sound signals as the basis for delivering stimulation signals to the user. Further details regarding operation of the cochlear implant 112 in the external hearing mode are provided below, followed by details regarding operation of the cochlear implant 112 in the invisible hearing mode. It is to be appreciated that reference to the external hearing mode and the invisible hearing mode is merely illustrative and that the cochlear implant 112 could also operate in alternative modes.

[0031] In FIGs. 1 A and 1C, the cochlear implant system 102 is shown with an external device 110, configured to implement aspects of the techniques presented. The external device 110 is a computing device, such as a personal computer (e.g., laptop, desktop, tablet), a mobile phone (e.g., smartphone), a remote control unit, etc. The external device 110 and the cochlear implant system 102 (e.g., sound processing unit 106 or the cochlear implant 112) wirelessly communicate via a bi-directional communication link 126. The bi-directional communication link 126 can comprise, for example, a short-range communication, such as Bluetooth link, Bluetooth Low Energy (BLE) link, a proprietary link, etc.

[0032] Returning to the example of FIGs. 1 A-1D, the sound processing unit 106 of the external component 104 also comprises one or more input devices configured to capture and / or receive input signals (e.g., sound or data signals) at the sound processing unit 106. The one or more input devices include, for example, one or more sound input devices 118 (e.g., one or moreAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIexternal microphones, audio input ports, telecoils, etc.), one or more auxiliary input devices 128 (e.g., audio ports, such as a Direct Audio Input (DAI), data ports, such as a Universal Serial Bus (USB) port, cable port, etc.), and a short-range wireless transmitter / receiver (wireless transceiver) 120 (e.g., for communication with the external device 110), each located in, on, or near the sound processing unit 106. However, it is to be appreciated that one or more input devices can include additional types of input devices and / or less input devices (e.g., the short-range wireless transceiver 120 and / or one or more auxiliary input devices 128 could be omitted).

[0033] The sound processing unit 106 also comprises the external coil 108, a charging coil 130, a closely-coupled radio frequency transmitter / receiver (RF transceiver) 122, at least one rechargeable battery 132, and an external processing module 124. The external processing module 124 can be configured to perform a number of operations that are represented in FIG. ID by an electrical potential measurement module 131 and a sound processor 133. Each of the electrical potential measurement module 131 and the sound processor 133 can be formed by one or more processors (e.g., one or more Digital Signal Processors (DSPs), one or more uC cores, etc.), firmware, software, etc. arranged to perform operations described herein. That is, the electrical potential measurement module 131 and the sound processor 133 can each be implemented as firmware elements, partially or fully implemented with digital logic gates in one or more application-specific integrated circuits (ASICs), partially or fully in software, etc. Although FIG. ID illustrates the electrical potential measurement module 131 and a sound processor 133 as being implemented / performed at the external processing module 124, it is to be appreciated that these elements (e.g., functional operations) could also or alternatively be implemented / performed as part of the implantable processing module 158, as part of the external device 110, as a separate, dedicated device / system, etc.

[0034] Returning to the example of FIGs. 1A-1D, the cochlear implant 112 comprises an implant body (main module) 134, a lead region 136, and the stimulating assembly 116, all configured to be implanted under the skin (tissue) 115 of the user. The implant body 134 generally comprises a hermetically-sealed housing 138 that includes, in certain examples, at least one power source 125 (e.g., one or more batteries, one or more capacitors, etc.), in which the RF interface circuitry 140 and a stimulator unit 142 are disposed. The implant body 134 also includes the internal / implantable coil 114 that is generally external to the housing 138, but which is connected to the RF interface circuitry 140 via a hermetic feedthrough (not shown in FIG. ID).Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0035] As noted, the stimulating assembly 116 is configured to be at least partially implanted in the user’s cochlea. The stimulating assembly 116 includes a plurality of longitudinally spaced intra-cochlear electrical stimulating contacts (electrodes) 144 that collectively form a contact array (electrode array) 146 for delivery of electrical stimulation (current) to the recipient’s cochlea. The stimulating assembly 116 extends through an opening in the recipient’s cochlea (e.g., cochleostomy, the round window, etc.) and has a proximal end connected to stimulator unit 142 via lead region 136 and a hermetic feedthrough (not shown in FIG. ID). The lead region 136 includes a plurality of conductors (wires) that electrically couple the electrodes 144 to the stimulator unit 142. The cochlear implant 112 also includes an electrode outside of the cochlea, sometimes referred to as an extra-cochlear electrode (ECE) 139.

[0036] As noted, the cochlear implant system 102 includes the external coil 108 and the implantable coil 114. The external magnet 150 is fixed relative to the external coil 108, and the internal / implantable magnet 152 is fixed relative to the implantable coil 114. The external magnet 150 and the internal / implantable magnet 152 fixed relative to the external coil 108 and the internal / implantable coil 114, respectively, facilitate the operational alignment of the external coil 108 with the implantable coil 114. This operational alignment of the coils enables the external component 104 to transmit data and power to the cochlear implant 112 via a closely-coupled wireless link 148 formed between the external coil 108 with the implantable coil 114. In certain examples, the closely-coupled wireless link 148 is an RF link. However, various other types of energy transfer, such as infrared (IR), electromagnetic, capacitive and inductive transfer, can be used to transfer the power and / or data from an external component to an implantable component and, as such, FIG. ID illustrates only one example arrangement.

[0037] As noted above, the sound processing unit 106 includes the external processing module 124. The external processing module 124 is configured to process the received acoustic signals (received at one or more of the input devices, such as sound input devices 118 and / or auxiliary input devices 128) and convert the received acoustic signals into output control signals for use in stimulating a first ear of a recipient or user (i.e., the external processing module 124 is configured to perform sound processing on input signals received at the sound processing unit 106). Stated differently, the one or more processors (e.g., processing element(s) implementing firmware, software, etc.) in the external processing module 124 are configured to execute sound processing logic in memory to convert the received acoustic signals into output control signals (stimulation signals) that represent electrical stimulation for delivery to the recipient.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0038] As noted, FIG. ID illustrates an embodiment in which the external processing module 124 in the sound processing unit 106 generates the output control signals. In an alternative embodiment, the sound processing unit 106 can send less processed information (e.g., audio data) to the cochlear implant 112, and the sound processing operations (e.g., conversion of input sounds to output control signals 156) can be performed by a processor within the cochlear implant 112.

[0039] In FIG. ID, according to an example embodiment, output control signals (stimulation signals) are provided to the RF transceiver 122, which transcutaneously transfers the output control signals (e.g., in an encoded manner) to the cochlear implant 112 via the external coil 108 and the implantable coil 114. That is, the output control signals (stimulation signals) are received at the RF interface circuitry 140 via the implantable coil 114 and provided to the stimulator unit 142. The stimulator unit 142 is configured to utilize the output control signals to generate electrical stimulation signals (e.g., current signals) for delivery to the user’s cochlea via one or more of the stimulating contacts 144. In this way, the cochlear implant system 102 electrically stimulates the user’s auditory nerve cells, bypassing absent or defective hair cells that normally transduce acoustic vibrations into neural activity, in a manner that causes the recipient to perceive one or more components of the acoustic signals (the received sound signals).

[0040] In addition, the stimulator unit 142 includes one or more amplifiers 143. As described further below, the one or more amplifiers 143 are configured to capture signals (e.g., electrical potential measurements from the cochlea of the recipient.

[0041] As detailed above, in the external hearing mode, the cochlear implant 112 receives processed sound signals from the sound processing unit 106. However, in the invisible hearing mode, the cochlear implant 112 is configured to capture and process sound signals for use in electrically stimulating the user’s auditory nerve cells. In particular, as shown in FIG. ID, an example embodiment of the cochlear implant 112 can include a plurality of implantable sound sensors 165(1), 165(2) that collectively form a sensor array 160, and an implantable processing module 158. Similar to the external processing module 124, the implantable processing module 158 can comprise, for example, one or more processors and a memory device (memory) that includes sound processing logic. The memory device can comprise any one or more of Non-Volatile Memory (NVM), Ferroelectric Random Access Memory (FRAM), read only memory (ROM), random access memory (RAM), magnetic disk storage media devices, optical storage media devices, flash memory devices, electrical, optical, or other physical / tangible memoryAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIstorage devices. The one or more processors are, for example, microprocessors or microcontrollers that execute instructions for the sound processing logic stored in memory device.

[0042] In the invisible hearing mode, the implantable sound sensors 165(1), 165(2) of the sensor array 160 are configured to detect / capture input sound signals 166 (e.g., acoustic sound signals, vibrations, etc.), which are provided to the implantable processing module 158. The implantable processing module 158 is configured to convert received input sound signals 166 (received at one or more of the implantable sound sensors 165(1), 165(2)) into output control signals 156 for use in stimulating the first ear of a recipient or user (i.e., the implantable processing module 158 is configured to perform sound processing operations). Stated differently, the one or more processors (e.g., processing element(s) implementing firmware, software, etc.) in the implantable processing module 158 are configured to execute sound processing logic in memory to convert the received input sound signals 166 into output control signals 156 that are provided to the stimulator unit 142. The stimulator unit 142 is configured to utilize the output control signals 156 to generate electrical stimulation signals (e.g., current signals) for delivery to the user’s cochlea, thereby bypassing the absent or defective hair cells that normally transduce acoustic vibrations into neural activity.

[0043] It is to be appreciated that the above description of the so-called external hearing mode and the so-called invisible hearing mode are merely illustrative and that the cochlear implant system 102 could operate differently in different embodiments. For example, in one alternative implementation of the external hearing mode, the cochlear implant 112 could use signals captured by the sound input devices 118 and the implantable sound sensors 165(1), 165(2) of sensor array 160 in generating stimulation signals for delivery to the user.

[0044] As noted above, presented herein are techniques for evaluating the characteristics of a body chamber of a recipient of a medical device (medical device recipient) through the use of electrical position measurement / monitoring. In certain examples, the recipient is a cochlear implant recipient and the body chamber is the cochlea or inner ear of the recipient. Merely for ease of description, the techniques presented herein are primarily described with reference to evaluating characteristics of a cochlea of a cochlear implant recipient. However, again, reference to a cochlea or a cochlear implant is merely illustrative and the techniques presented herein can be implemented with / by a variety of medical devices and a variety of body chambers of a recipient.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0045] In accordance with illustrative embodiments presented herein, and as shown in FIG. IE, a system (e.g., cochlear implant system 102) delivers one or more current pulses to the cochlea to generate an electrical potential 145 at a first location in the cochlea. After generation of the electrical potential 145, the system induces motion of (vibrates) the perilymph (fluid in the scala tympani of the cochlea), while contemporaneously measuring the electrical potential 145 at the first location the cochlea. In operation, the motion induced in the perilymph can cause changes / variations in the electrical potential at the first location, where the changes / variations in the electrical potential are captured in the electrical potential measurement at the first location. As such, the system can use the measured electrical potential (e.g., changes / variations in the electrical potential or lack thereof) to evaluate one or more characteristics of the cochlea.

[0046] For example, aspects of the techniques presented herein provide a mechanism that makes it possible to measure vibrations inside the cochlea, caused by delivered stimulation signals (e.g., acoustic stimulation, vibratory stimulation, mechanical stimulation, etc.), and, in turn, assess / evaluate characteristics of the cochlea, such as the ability of the perilymph inside the scala tympani to transmit sounds. Evaluation of the ability of the perilymph inside the scala tympani to transmit sound can, in particular, be an important indicator of the level of otosclerosis inside the cochlea, as well as an indicator of the ability of the cochlea to continue to provide some level of residual hearing. Additionally, the mechanism can correlate transmission of audio at specific frequencies with locations of electrodes -a factor than can be useful for tonotopic audio mapping.

[0047] As noted, and as described further below, the electrical potential measurements are performed by artificially creating an electrical potential inside the perilymph and then delivering stimulation, such as acoustic stimulation, to the cochlea. Using an amplifier, vibration of the fluid containing the electrical potential can be measured, which in turn is indicative of the acoustic stimulation that inducted the vibrations inside the cochlea. In certain examples, the electrical potential is created by delivering a relatively small monophasic pulse via an electrode in the cochlea, where the relatively small monophasic pulse creates an ionic potential in the perilymph. By subsequently exposing the recipient to a frequency sweep (e.g., acoustic stimulation at a plurality of different frequencies), the acoustic frequency can be correlated to an electrode location, depending on when the measured electrode pair “triggers” (i.e., measures a vibration) during the sweep. The measurement is performed with a relativelyAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIshort time window after creation of the electrical potential (e.g., before the potential dissipates into the fluid via natural diffusion processes).

[0048] Different locations of the cochlea can have different characteristics, such as acoustic transmission characteristics. As an example, the cochlea is tonotopically mapped in that each region of the cochlea is acoustically responsive to acoustic signals in a respective, particular frequency range. In general, more basal regions of the cochlea adjacent to an opening of the cochlea is responsive to higher frequency sounds, while more apical regions of the cochlea further from the opening of the cochlea are responsive to lower frequency sounds. As another example, different locations of the cochlea can have varying health statuses that impact acoustic transmission. For instance, ossification and / or tissue damage can reduce acoustic transmission at some locations but not at other locations.

[0049] The electrical potential measurement techniques described herein can be used to evaluate the above or characteristics of the cochlea. In particular, certain stimulation signals (e.g., acoustic signals, vibration signals, mechanical stimulation signals, etc.) delivered to a recipient can induce motion of the perilymph within the cochlea. In a normal function cochlea, the motion can pass through all or a portion of the cochlea (e.g., depending on intensity, frequency, or other attributes). However, in certain cases, the cochlea could suffer from ossification and / or tissue damage at one or more locations, which impede the ability of the cochlea fluid to move in response to stimulation signals (e.g., reduce acoustic transmission at some locations but not at other locations). The electrical potential measurements presented herein can be used to characterize the motion of the perilymph, and therefore the ability of the cochlea to transmit sound, in response to a stimulation signal. For example, the vibration of the perilymph fluid causes ions effectuating the electrical potential to oscillate, thereby causing measurements of the electrical potential to oscillate. Therefore, oscillations of the electrical potential measurements can be used to evaluate the acoustic transmission characteristics of the cochlea. By measuring electrical potential, acoustic transmission characteristics can be determined without measuring a neural response.

[0050] As noted above, a cochlea of a recipient can have different characteristics at different locations. It is desirable to determine such characteristics to improve operation of a device / system utilizing functionality and / or structure of the cochlea. As an example, a cochlear implant system (e.g., the cochlear implant system 102) can be better implanted in the recipient, such as by aligning electrodes (e.g., the electrodes 144) more suitably, to improve operation of the cochlea implant system to provide hearing benefits to the recipient.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0051] It should be noted that techniques discussed herein can be implemented in any suitable cochlear implant system, such as a totally implantable cochlear implant system, a mostly implantable cochlear implant system, and / or a cochlear system with no sound processor / extemal component. Moreover, the techniques discussed herein can be implemented using other devices / systems, such as electrodes of a stent and / or a deep brain stimulator. Therefore, the techniques can be performed for other anatomical locations of a recipient. For instance, the electrical potential measurement techniques can be performed to measure changes in blood viscosity or other suitable characteristics that are related to electrical potential measurements.

[0052] FIGs. 2A and 2B are schematic diagrams illustrating aspects of a system 270 configured to measure electrical potential at different locations of a cochlea 272 of an ear 274 of a recipient and to evaluate characteristics of the cochlea 272 using the electrical potential measurements. For ease of descriptions, FIGs. 2 A and 2B will generally be described together. In addition, also for ease of illustration, FIGs. 2A and 2B will be described with reference to cochlear implant system 102 of FIGs. 1A-1E.

[0053] In this example, the system 270 includes cochlear implant system 102, which comprises, along other elements, the sound processing unit 106 and cochlear implant 112. For ease of illustration, cochlear implant 112 is shown in a simplified form with only implant body 134, stimulating assembly 116 (FIG. 2B), and lead 136 visible in FIG. 2A.

[0054] The system 270 also includes an audio source 276 (e.g., a hearing aid, a headphone, an earphone, a speaker) that is positioned at the ear 274 of the recipient. As noted below, the audio source 276 is configured to deliver acoustic stimulation (acoustic signals) 278 to induce motion of the perilymph in the cochlea 272.

[0055] During operation of the system 270, the cochlear implant system 102 is controlled to selectively stimulate the cochlea 272 to generate an electrical potential at a selected location in the cochlea. Meanwhile, the audio source 276 is controlled to deliver the acoustic stimulation 278, which induces motion of (vibrates) the perilymph. Contemporaneously, with delivery of the acoustic stimulation 278, cochlear implant system 102 (e.g., via amplifiers 143) measures / monitors the electrical potential at the selected location.

[0056] As noted above, motion of the perilymph in response to the acoustic stimulation 278 can induce oscillation / vibration of the electrical potential at the selected location. However, characteristics of the cochlea 272 at the selected location can affect how the electrical potentialAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIoscillates in response to acoustic signals 278 having a particular frequency. Thus, the electrical potential measurements (e.g., electrical potential oscillations or lack thereof) at the selected location, along with the frequency or frequencies of the acoustic stimulation 278 delivered to the cochlea 272, can be used to evaluate the characteristics of the selected location.

[0057] It is to be appreciated that acoustic stimulation 278 can be delivered in a number of different manners and can have a number of different attributes. In certain embodiments, the system 270 can characterize the transmission of the acoustic signal in various sections of the intracochlear environment through the delivery of a plurality of controlled acoustic signals. This can be achieved by the recipient wearing master hearing aids (e.g., inserted into the ear canal) or having well-calibrated and high-powered speakers inserted into the ear canal. Tones can be played at different frequencies and magnitudes. One mode of the presentation of acoustic signals in techniques presented herein is referred to herein as a “frequency sweep” at a particular amplitude, from low frequencies to high frequencies. That is, in this example, acoustic stimulation 278 comprises a plurality of acoustic signals delivered at a series of different frequencies and a set amplitude. Sound propagates through the ear canal, causing the tympanic membrane and auditory ossicles to vibrate, the stirrup of the auditory ossicles transmits the vibration to the cochlea (e.g., which induces a standing wave forms inside of the cochlea that, in turn can oscillate the electrical potential).

[0058] FIGs. 2C and 2D are schematic front and side views, respectively, of a recipient of cochlear implant system 102 wearing a master hearing aid in a clinical setting. In this arrangement, the recipient also wears the sound processing unit 106. During the delivery of the acoustic stimulation 278, the sound processing unit 106 can remain online, however the microphones of the sound processor are disabled.

[0059] In some embodiments, bipolar monophasic stimulation is used to stimulate a selected location of the cochlea 272 in which a first electrode 144 is provided with current (i.e., the electrode 144 is sourced with current) and a second electrode 144 is used to ground or sink current. For example, at least one of (e.g., both of) the electrodes 144 is aligned with or proximate to the selected location to provide current flow that stimulates the selected location. However, other methods of stimulation can be used to generate an electrical potential at the selected location. In any case, the stimulation creates an electrical potential (e.g., a shift in potential gradient) in the solution within the perilymph fluid within the cochlea 272.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0060] FIGs. 2A and 2B have been described with reference to measuring the electrical potential at a selected location. It is to be appreciated that, in certain embodiments, the operations described above with reference to FIGs. 2A and 2B can be repeated at a plurality of locations in the location to obtain a plurality of electrical potential measurements that can be collectively used to evaluate characteristics of the cochlea. More specifically, because each electrode 144 is positioned at a different location of the cochlea 272, different electrodes 144 can be used to capture electrical potential measurements at different locations and, accordingly, evaluate characteristics at each location. That is, for each of a plurality of locations in the cochlea 272, a corresponding one of the electrodes 144 provides stimulation to generate an electrical potential at the corresponding location. The audio source 276 delivers the acoustic stimulation 278, and, contemporaneously, the electrical potential is measured at the corresponding location. The characteristics of the cochlea, in genera or at each of the plurality of locations can then be evaluated based on the plurality of electrical potential measurements.

[0061] FIG. 3A is a schematic view of an electrical potential generated at a cochlea using a first technique presented herein. Specifically, during stimulation, current is sourced by a stimulating electrode 344A and sunk by a ground electrode 344B to create an ionic potential in perilymph fluid 399 of the cochlea. Consequently, the stimulating electrode 344A (cathode) is negatively charged, and the ground electrode 344B (anode) is positively charged. In response, positively charged ions 380 (e.g., positively charged platinum ions) in the perilymph fluid are attracted to the stimulating electrode 344A, whereas negatively charged ions 382 in the perilymph fluid are attracted to the ground electrode 344B. Reduction occurs at the stimulating electrode 344A to cause the positively charged ions to bind thereto. Meanwhile, oxidation occurs at the ground electrode 344B to cause positively charged ions (e.g., positively charged platinum ions) to be released. The movement of ions in the perilymph fluid of the cochlea creates an electrical potential between the stimulating electrode 344A and the ground electrode 344B, and such an electrical potential is measured / monitored (following delivery of acoustic stimulation to the cochlea) and used to determine the characteristics of the cochlea. Once current flow through the electrodes 344 is suspended to cease stimulation, the charge of the electrodes 344 are removed, and the ions disperse via diffusion to reduce the electrical potential between the stimulating electrode 344A and the ground electrode 344B.

[0062] In the illustrated first technique, the stimulating electrode 344A and the ground electrode 344B are separated from one another by an intermediate electrode 344C. That is, the intermediate electrode 344C is immediately adjacent to both the stimulating electrode 344AAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIand the ground electrode 344B. For example, the stimulating electrode 344A and the ground electrode 344B are positioned such that one of the stimulating electrode 344A or the ground electrode 344B is proximate to the location of stimulation, whereas the other of the stimulating electrode 344A or the ground electrode 344B is positioned away from the location of stimulation. A first outer electrode 344D is immediately adjacent to the stimulating electrode 344A but not the ground electrode 344B, and a second outer electrode 344E is immediately adjacent to the ground electrode 344B but not the stimulating electrode 344A. In other words, the stimulating electrode 344A is immediately adjacent to the first outer electrode 344D and the intermediate electrode 344C, whereas the ground electrode 344B is immediately adjacent to the intermediate electrode 344C and the second outer electrode 344E. Therefore, the electrodes 344A, 344B through which current flows are interleaved. In an arrangement in which the stimulating electrode 344A and the ground electrode 344B are separated from one another by one or more intermediate electrodes 344C, the electrical potential between the stimulating electrode 344A and the ground electrode 344B are determined based on the electrical potential associated with electrodes 344 immediately adjacent thereto.

[0063] That is, in the illustrated arrangement, the electrical potential between the intermediate electrode 344C and the first outer electrode 344D is determined by measuring a first electrical potential around the stimulating electrode 344A, and the electrical potential between the intermediate electrode 344C and the second outer electrode 344E is determined by measuring a second electrical potential around the ground electrode 344B. In this manner, the intermediate electrode 344C is used to measure the electrical potential around both the stimulating electrode 344A and the ground electrode 344B. A difference between the first electrical potential and the second electrical potential is then determined as the electrical potential between the stimulating electrode 344A and the ground electrode 344B.

[0064] In an arrangement in which multiple intermediate electrodes 344C are positioned between the stimulating electrode 344A and the ground electrode 344B (i.e., different intermediate electrodes 344 are immediately adjacent to the stimulating electrode 344A and the ground electrode 344B), a different intermediate electrode 344 is used to measure the electrical potential around the stimulating electrode 344A and the electrical potential around the ground electrode 344B. Specifically, the electrical potential between a first intermediate electrode 344 and the first outer electrode 344D is determined to measure the first electrical potential around the stimulating electrode 344A, and the electrical potential between the intermediate electrode 344 and the second outer electrode 344E is determined to measure theAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIsecond electrical potential around the ground electrode 344B. Regardless, the electrical potential between the stimulating electrode 344A and the ground electrode 344B is determined based on the first electrical potential around the stimulating electrode 344A and the second electrical potential around the ground electrode 344B.

[0065] While the electrical potential between the stimulating electrode 344A and the ground electrode 344B is generated via stimulation, acoustic signals delivered to the recipient vibrate the perilymph fluid 399 and correspondingly cause the charged ions 380, 382 within the perilymph fluid to oscillate. Oscillation of the charged ions 380, 382 correspondingly oscillate electrical potential measurements, which are dependent of the position of the charged ions 380, 382. The oscillations of the electrical potential measurements can be used to evaluate characteristics of the cochlea.

[0066] FIG. 3B is a schematic view of an electrical potential generated at a cochlea using a second technique. In the second technique, the stimulating electrode 344A sourcing current and the ground electrode 344B sinking current are immediately adjacent to one another. That is, no intermediate electrodes 344 separate the stimulating electrode 344A and the ground electrode 344B from one another. For example, each of the stimulating electrode 344A and the ground electrode 344B is proximate to a location of stimulation of the cochlea. During stimulation, a similar movement of charged ions 380, 382 in the perilymph fluid 399 occurs to increase the electrical potential between the stimulating electrode 344A and the ground electrode 344B. In the illustrated arrangement, the stimulating electrode 344A and the ground electrode 344B themselves are used to measure the electrical potential. That is, because there are no intermediate electrodes immediately adjacent to the stimulating electrode 344 A and to the ground electrode 344B, the electrical potential between the stimulating electrode 344A and the ground electrode 344B is directly determined based on a potential different between the stimulating electrode 344A and the ground electrode 344B.

[0067] FIG. 4 graphically illustrates the values of various parameters over a period of time during which electrical potential is generated at a location of a cochlea. More specifically, FIG. 4 includes a first graph 401 illustrating current (in amperes) that is provided to stimulate the location of the cochlea over the period of time. In particular, current (at a selected amplified) is delivered during a stimulation phase 403 to stimulate the location of the cochlea via an electrode positioned at the location. For example, a stimulating electrode sources the provided current, whereas a grounding electrode sinks the provided current. The current flow causes movement of ions in perilymph fluid within the cochlea to generate an electricalAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIpotential at the location. The current flow is then ceased / terminated after the stimulation phase 403. For example, the stimulation is provided as a transient pulse (e.g., a monophasic pulse).

[0068] FIG. 4 also includes a second graph 405 that illustrates an acoustic stimulation (in decibels (dB)) being provided over the period of time. In the illustrated embodiment, the acoustic stimulation comprises an acoustic signal delivered at a selected acoustic frequency 407 over the entire period of time. In this example, the acoustic signal is provided before the stimulation phase 403, as well as after the stimulation phase 403. However, in additional or alternative embodiments, the acoustic signal is delivered for only a portion of the period of time (e.g., only during the stimulation phase 403). In either case, the acoustic signal includes motion / vibration in the perilymph fluid to cause the ions in the perilymph fluid to oscillate.

[0069] FIG. 4 also includes a third graph 409 that illustrates the absolute value of an electrical potential measured within the cochlea. In particular, the third graph 409 includes a first line 411 (i.e., a non-oscillatory line) indicating an expected electrical potential generated by stimulation without the acoustic signal causing oscillations of the perilymph fluid. As shown, the first line 411 increases during the stimulation phase 403 and then decreases after the stimulation phase 403, thereby indicating stimulation current increases the electrical potential by inducing ion flow and a lack of stimulation current results in a decrease in the electrical potential via natural diffusion of ions.

[0070] The third graph 409 also includes a second line 413 (i.e., an oscillatory line) indicating the electrical potential generated by stimulation in conjunction with the acoustic signal causing oscillations of the perilymph fluid. The second line 413 follows the first line 411 by increasing during the stimulation phase 403 and decreasing after the stimulation phase 403. However, because the second line 413 is provided by measuring electrical potentials while an acoustic signal is delivered, the second line 413 also oscillates as a result of movement (e.g., oscillation) of ions in the perilymph fluid caused by vibrations induced via the acoustic signal. The oscillations of the second line 413 can be used to determine characteristics of the cochlea.

[0071] In certain embodiments, the first line 411 is used as a reference line for comparison with the second line 413 to ensure that electrical potentials are being accurately generated / measured. For instance, the first line 411 is provided by measuring electrical potential in response to stimulation without providing acoustic signals and the second line 413 is provided by measuring electrical potential in response to stimulation while providing acoustic signals. The first line 411 and the second line 413 are then compared with one another.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIA determination is made that the electrical potentials are being accurately measured based on the second line 413 substantially following the first line 411, thereby indicating a similar trajectory of electrical potential is being provided with and without an acoustic signal.

[0072] Analyzing the oscillations of the second line 413 can include determining a fundamental frequency 415 (e.g., a first harmonic) of the second line 413 and comparing the fundamental frequency 415 to the acoustic frequency 407 of the acoustic signals. A substantial match between the fundamental frequency 415 and the acoustic frequency 407 (e.g., a difference between the fundamental frequency 415 and the acoustic frequency 407 being below a threshold) indicates the location of the cochlea corresponds to the acoustic signal having the acoustic frequency 407. That is, the perilymph fluid at the location of the cochlea readily transmits sound at the acoustic frequency 407 by generating vibrations in response to audio stimulus.

[0073] Meanwhile, a substantial difference between the fundamental frequency 415 and the acoustic frequency 407 (e.g., a difference between the fundamental frequency 415 and the acoustic frequency 407 exceeds a threshold) indicates the location of the cochlea does not correspond to the acoustic signal having the acoustic frequency 407. That is, sound at the acoustic frequency 407 does not induce oscillation of the perilymph fluid at the location of the cochlea to cause the acoustic frequency 407 to transmit sound at the acoustic frequency 407. As an example, the location of the cochlea has ossified or otherwise is not responsive to acoustic stimulus at the acoustic frequency 407. Therefore, the measured electrical potential can be used to evaluate acoustic transmission characteristics that indicate health of the cochlea, as well as the potential for the location of the cochlea to provide some level of residual hearing. For instance, a mismatch between the fundamental frequency 415 and the acoustic frequency 407 can be characterized as a substantial level of otosclerosis, a substantial amount of fibrosis, or other issues that inhibits the location of the cochlea from transmitting sound at the acoustic frequency 407.

[0074] In some cases, the location of the cochlea is responsive to acoustic stimuli of some acoustic frequencies but not to other acoustic frequencies. For this reason, acoustic signals of varying frequencies are delivered to the cochlea, such as with a frequency sweep that gradually / incrementally increases the frequency of the acoustic signals from a low frequency to a high frequency or vice versa. For each acoustic signal, the electrical potential is measured at the location (e.g., by stimulating via an electrode at the location) to determine a fundamental frequency 415 for comparison with the corresponding acoustic frequency 407 of the acousticAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIsignal being delivered. After the electrical potentials are measured for each acoustic signal, a determination is made regarding whether any of the acoustic signals trigger or induce an electrical potential having a matching fundamental frequency 415 to correspond the acoustic frequency 407 of such an acoustic signal with the location of the cochlea. After the electrical potentials are measured at the location, stimulation is provided to a different location (e.g., via another electrode at the different location), and acoustic signals of varying frequencies are delivered to the cochlea again to determine whether any of the acoustic signals trigger or induce an electrical potential having a matching fundamental frequency 415. In this manner, electrical potentials can be generated and measured at each location while acoustic signals of varying frequencies are delivered to evaluate the respective acoustic transmission characteristics at each location of the cochlea.

[0075] Each of FIGs. 5 A, 5B, 6, 7, and 8 is a flowchart of an embodiment of a method related to measuring an electrical potential in a cochlea, in accordance with embodiments presented herein. It should be noted that any of the methods can be performed differently than depicted. For example, an additional operation of any of the methods can be performed, and / or an operation of any of the method can be performed differently, performed in a different order, and / or not performed. Moreover, the respective operations of each method can be performed in any suitable manner relative to one another, such as in response to and / or in parallel to one another.

[0076] FIG. 5 A is a flowchart of a method 517A for evaluating acoustic transmission characteristics of a cochlea of a recipient. At least a portion of the method 517A can be performed by a cochlear implant at least partially implanted in the recipient. At block 519, an electrical potential is generated at a location of the cochlea. For instance, a stimulating electrode sources current and a grounding electrode sinks current to create an ionic potential in perilymph fluid in the cochlea. The ionic potential causes ions to move and create a potential gradient between the stimulating electrode and the grounding electrode.

[0077] At block 521, acoustic signals are delivered to vibrate the cochlea. In particular, the acoustic signals are delivered into an ear of the recipient, and the acoustic signals generate vibrations of structure in the ear, which propagate to the cochlea. The acoustic signals can vibrate the perilymph fluid, thereby oscillating the ions within the perilymph fluid and affecting the potential gradient created by movement of the ions. In some embodiments, acoustic signals of varying frequencies are delivered, and the acoustic signals of varying frequencies can cause different oscillations of ions. In certain implementations, an operation of a microphone of theAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIcochlear implant is suspended to avoid unwanted operation of the cochlear implant in response to the acoustic signals. For example, suspending operation of the microphone can avoid operation of the cochlear implant to receive and process the acoustic signals (e.g., and subsequently convert the acoustic signals to stimulation signals used to stimulate the cochlea), even while a sound processor of the cochlear implant remains active.

[0078] At block 523, the electrical potential is measured at the location of the cochlea. In some embodiments, the electrical potential is directly measured as a potential difference between the stimulating electrode and the grounding electrode. In additional or alternative embodiments, electrodes immediately adjacent to the stimulating electrode and the grounding electrode are used to measure the electrical potential at the location. For instance, a first electrical potential around the stimulating electrode is determined based on the potential difference between the electrodes immediately adjacent to the stimulating electrode, a second electrical potential around the grounding electrode is determined based on the potential difference between the electrodes immediately adjacent to the grounding electrode, and a difference between the first electrical potential and the second electrical potential is then determined as the electrical potential at the location of the cochlea.

[0079] At block 525, acoustic transmission characteristics of the cochlea are evaluated based on the measured electrical potential. In particular, oscillation of the ions caused by the acoustic signals can fluctuate the potential gradient between the stimulating electrode and the grounding electrode, thereby oscillating the electrical potential measured at the location where an electrical potential is generated. Thus, the oscillation of the measured electrical potential can indicate the ability of the cochlea to transmit sound at the location.

[0080] It should be noted that the operations of 519, 521, 523, and 525 could be performed for a single location, or multiple locations, before the operations of 525 are performed. For example, in some embodiments, the evaluation / analysis at 525 is related to a single cochlea location. However, in other examples, the evaluation / analysis at 525 is related, or based on, a plurality of locations. In these embodiments, the operations of 519, 521, 523, and 525 would be performed at a plurality of different locations, and the resulting measurements would be collectively evaluated / analyzed at 525.

[0081] In certain examples, the method 517 A can be repeated over time to monitor the acoustic transmission characteristics of the cochlea over time. For example, the change in acoustic transmission characteristics of the cochlea can indicate a change in health (e.g., a growth inAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIfibrous tissue, a growth in ossification) and / or a change in functionality (e.g., a change in residual hearing ability) of the cochlea over time.

[0082] It should also be noted that the method 517A can be repeated for multiple locations in the cochlea. That is, electrical potentials (e.g., of similar values / amplitudes) can be generated at different locations while acoustic signals are delivered to the cochlea, and the generated electrical potentials can be measured to evaluate acoustic transmission characteristics of each location. Thus, an overall evaluation of the cochlea can be performed, such as by correlating acoustic frequencies with corresponding locations, as well as electrodes positioned at the locations, in the cochlea to indicate the acoustic frequencies that can be readily transmitted at different locations of the cochlea. In embodiments in which the method 517A is repeated, the ionic potential in the perilymph fluid is recovered between iterations of performing the method 517A.

[0083] For example, a charge balancing pulse (e.g., a stimulation of inverse polarity) is delivered to the cochlea and / or the stimulating electrode and the grounding electrode are short circuited (e.g., to an internal resistor bank of a cochlea implant). Recovering the ionic potential can avoid changing a structural integrity of the electrodes and / or of the cochlea, which otherwise could be caused by a lingering ionic potential. Moreover, recovering the ionic potential can more quickly place the perilymph fluid in condition to repeat the method 517A without a lingering ionic potential affecting stimulation to generate another electrical potential. Regardless, a threshold amount of time can elapse between iterations of performing the method 517A to ensure that a lingering ionic potential does not affect stimulation. In certain implementations, electrical potentials can continue to be measured before the threshold amount of time elapses to provide a sufficient amount of electrical potential measurements that can be used to evaluate acoustic transmission characteristics (e.g., to confirm a frequency of oscillation of the electrical potential measurements).

[0084] Furthermore, in embodiments in which the method 517A is repeated for multiple locations, the delivery of acoustic signals can be adjusted based on the acoustic transmission characteristics already evaluated for previous locations. By way of example, based on a first performance of the method 517A, a first location of the cochlea is determined to be able to transmit sound at a particular frequency. Thus, there is no need to determine whether a second location of the cochlea is also able to transmit sound at the particular frequency. That is, determining whether the second location is able to transmit sound at the particular frequency is redundant in view of the ability of the first location to transmit sound at the particularAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIfrequency. Therefore, while performing the method 517A for the second location, an acoustic signal of the particular frequency is not delivered. In this way, fewer acoustic signals (e.g., a smaller frequency sweep) can be utilized in subsequent iterations of the method 517A as determinations are made that locations of the cochlea are able to transmit sound at particular frequencies (e.g., as additional acoustic frequencies are correlated with locations).

[0085] FIG. 5B illustrates another method 517B that is similar to method 517A, except that in this example generation of the electrical potential is preceded, at 527, by delivery of a forward masker to cause the nerve cells at the location to enter a refractory period (e.g., an operation is performed to suppress nerve activity, which otherwise could interfere with electrical potential measurements, prior to measuring electrical potentials). In one example, the forward masker comprises one or more electrical signals (e.g., a biphasic masker pulse). As another example, forward masker comprises an agent (e.g., an anesthetic) that can be delivered to selectively suppress nerve activity. As such, in this example, oscillations of the electrical potential are isolated (from nerve firing) to avoid obfuscation with nerve responses.

[0086] In some embodiments, correlating acoustic frequencies with cochlea locations can then be used to establish or adjust how stimulation is being provided to different locations of the cochlea to help the recipient perceive sound more suitably. For instance, an acoustic transmission characteristic indicating that a location of the cochlea can readily transmit an acoustic signal of a particular frequency can suggest some residual hearing ability of the recipient to perceive sound at the particular frequency. Therefore, electrical stimulation that enables the recipient to perceive sound at the particular frequency can be avoided to, instead, allow the recipient to perceive such sound using the residual hearing ability.

[0087] For example, acoustic stimulation that amplifies sound at the particular frequency can be used instead. However, an acoustic transmission characteristic indicating that no location of the cochlea can readily transmit an acoustic signal of a particular frequency can suggest that the recipient does not have residual hearing ability to perceive sound at the particular frequency. Thus, electrical stimulation that enables the recipient to perceive sound at the particular frequency can be provided. In this manner, electrical stimulation can be established / adjusted based on the acoustic transmission characteristics to avoid electrically invoking the recipient to perceive sounds at frequencies that are readily transmitted by the perilymph fluid while electrically invoking the recipient to perceive sounds at frequencies that are not readily transmitted by the perilymph fluid.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0088] Additionally or alternatively, the tonotopic mapping of the cochlea can be established based on the acoustic transmission characteristics. As an example, an acoustic transmission characteristic indicating that a location of the cochlea can readily transmit an acoustic signal of a particular frequency can suggest that the location of the cochlea naturally receives sound at the particular frequency. In response, the electrode configured to stimulate the location can be mapped to the particular frequency (e.g., a range of frequencies encompassing the particular frequency) such that the electrode activates to help the recipient perceive sound at that particular frequency to mimic natural hearing. In either case, acoustic frequencies are correlated with electrodes based on their locations in the cochlea, and a frequency allocation table, which maps each electrode to a respective frequency or a respective range of frequencies of acoustic signals that causes activation of the electrode, can be calibrated accordingly based on the acoustic transmission characteristics.

[0089] FIG. 6 is a flowchart of a method 629 providing additional details regarding blocks 521 and 523 of the method 517A of FIG. 5A. In particular, blocks 631, 633, and 635 of the method 629 correspond to block 521 to illustrate a manner in which an acoustic signal can be generated and delivered to the cochlea, and blocks 637 and 639 of the method 629 correspond to block 523 to illustrate a manner in which electrical potentials are measured.

[0090] At block 631, an acoustic frequency signal is selected for analyzing the response in the cochlea. In some embodiments, the acoustic frequency signal is selected as a part of a frequency sweep for evaluating acoustic transmission characteristics. A certain acoustic frequency signal can be excluded, such as based on empirical data indicating that a location of the cochlea where electrical potentials are to be measured does not transmit such an acoustic frequency signal. At block 633, a magnitude / amplitude of the acoustic signal is selected. In particular, a sufficient magnitude / amplitude is selected to induce a vibration of perilymph fluid so that corresponding oscillation of electrical potential that can be captured (e.g., within the range of a sensor, such as an amplifier). At block 635, the acoustic signal is activated and delivered. Consequently, the acoustic signal vibrates the cochlea, such as perilymph fluid in the cochlea.

[0091] At block 637, a measurement sweep of electrical potentials across electrodes of an electrode array in the cochlea is performed while the acoustic signal is activated. That is, each electrode is positioned at a different location in the cochlea, and the measurement sweep includes measuring the electrical potential across each electrode and at each location. At block 639, the electrical potential measurement signal at each el ectrode / section of the electrode arrayAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIis output for further processing. For example, the electrical potential measurement at each section indicates an acoustic transmission characteristic at a corresponding location of the cochlea at where the section of the electrode is positioned. In particular, the acoustic signal can vibrate the perilymph fluid and oscillate the electrical potential measurement. Therefore, the oscillation of the electrical potential measurement, or lack thereof, indicates the ability of the cochlea to transmit the acoustic signal.

[0092] FIG. 7 is a flowchart of a method 745 of one embodiment of performing block 523 of the method 517A regarding measuring electrical potentials. In particular, the method 745 occurs while an acoustic signal is delivered (e.g., in accordance with block 521 of the method 517A) such that the perilymph fluid in the cochlea can vibrate.

[0093] At block 747, a section of an electrode array for measuring electrical potential is determined. In particular, a location of the cochlea of interest is selected, and one or more electrodes of the electrode array proximate to the location is determined. At block 749, a pair of electrodes is established to provide bipolar monophasic stimulation in which a stimulating electrode of the pair of electrodes sources current and a grounding electrode of the pair of electrodes sinks current.

[0094] At block 751, at least a pair of recording electrodes is established to measure an electrical potential difference for determining the electrical potential at the location of the cochlea. In some embodiments, the recording electrodes include the stimulating electrode and the grounding electrode (i.e., the electrical potential between the stimulating electrode and the grounding electrode is directly measured). In additional or alternative embodiments, the recording electrodes include electrodes that are immediately adjacent to the stimulating electrode and the grounding electrode. That is, the immediately adjacent electrodes are used to measure respective electrical potentials around the stimulating electrode and the grounding electrode, and a difference between the electrical potentials is used to measure the electrical potential at the location of the cochlea.

[0095] At block 753, a schedule of electrode stimulation and recording commands is derived. The schedule includes a timing between when current is provided to the electrode array (i.e., to flow between the stimulating electrode and the grounding electrode), thereby generating an electrical potential, and when the generated electrical potential is measured. At block 755, stimulating and recording commands, including the previously derived schedule, are provided to hardware to initiate stimulation and recording operations.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0096] At block 757, operation of a first timer initiates to trigger stimulation operations to initiate. At block 759, while operation of the first timer is ongoing, bipolar monophasic stimulation is provided via the established pair of electrodes by sourcing current at the stimulating electrode and sinking current at the grounding electrode. At block 761, the time increment of the first timer increases. At block 763, a determination is made regarding whether the time increment of the first timer indicates stimulation operations are to be suspended. In response to a determination that the time increment of the first timer does not indicate stimulation operations are to be suspended, bipolar monophasic stimulation, as performed at block 759, continues, and the time increment of the first timer continues to increase. However, in response to a determination that the time increment of the first timer indicates stimulation operations are to be suspended, bipolar monophasic stimulation is suspended, and operation of the first timer is also suspended.

[0097] Afterwards, at block 765, operation of a second timer initiates to trigger recording operations to initiate. At block 767, electrical potential at the selected location of the cochlea is measured using the established recording electrodes. For example, an amplifier is used to measure the electrical potential. Because recording operations occurs after stimulation has been suspended, cochlear stimulation and electrical potential measurement occur sequentially. At block 769, an individual electrical potential at a particular time increment indicated by the second timer is recorded. At block 771, the time increment of the second timer increases. At block 773, a determination is made regarding whether the time increment of the second timer indicates recording operations are to be suspended. In response to a determination that the time increment of the second timer does not indicate recording operations are to be suspended, the electrical potential continues to be measured, as performed at blocks 767 and 769, by recording another individual electrical potential measurement at another particular time increment (i.e., the newly increased time increment) as the time increment of the second timer continues to increase. Thus, electrical potential measurements at different particular time increments are repeatedly recorded to establish a timeseries of electrical potential measurements indicating a change in electrical potential over the time during which the recording operations are performed.

[0098] In response to a determination that the time increment of the second timer indicates recording operations are to be suspended, measurement of electrical potentials is suspended, and operation of the second timer is also suspended. Afterwards, at block 775, frequency analysis is conducted on the timeseries of electrical potential measurements. As discussed, theAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIacoustic signal can vibrate the perilymph fluid. As a result, the electrical potential can oscillate, and the frequency analysis includes determining a frequency of the possible oscillations of electrical potential measurements as caused by the acoustic signal.

[0099] At block 777, a phase analysis is conducted between the timeseries of electrical potential measurements and the acoustic signal being delivered. By way of example, the phase analysis includes comparing the frequency of the oscillation of electrical potential measurements, as indicated by the timeseries of electrical potential measurements, to the frequency of the acoustic signal. At block 779, a concordance between the timeseries of electrical potential measurements and the acoustic signal is determined. For example, the concordance is determined based on a difference between the frequency of the oscillation of electrical potential measurements and the frequency of the acoustic signal. In particular, the difference being below a threshold indicates that the acoustic signal at the frequency causes corresponding oscillations of the perilymph fluid and electrical potential measurements and, therefore, the perilymph fluid readily transmits such an acoustic signal. In other words, the selected section of the electrode array correlates to the frequency of the acoustic signal. At block 781, a determination is made regarding whether electrical potentials have been measured at all sections of the electrode array. In response to a determination that electrical potentials have not been measured at all sections of the electrode array, a new section of the electrode array is determined, and the method 745 is repeated for the new section (i.e., by performing stimulating operations, recording operations, and frequency / phase analysis associated with the new section). However, in response to a determination that electrical potentials have been measured at all sections of the electrode array, the method 745 is completed.[ooioo] FIG. 8 is a flowchart of a method 845 of another embodiment of performing block 523 of the method 517A regarding measuring electrical potentials. The method 845 also occurs while an acoustic signal is delivered (e.g., in accordance with block 521 of the method 517A) such that the perilymph fluid in the cochlea can vibrate.[ooioi] At block 847, a section of an electrode array for measuring electrical potential is determined, such as by determining one or more electrodes at a location of the cochlea to be evaluated. At block 849, a pair of electrodes is established to provide bipolar monophasic stimulation. At block 851, at least a pair of recording electrodes is established to measure an electrical potential difference for measuring the electrical potential at the location of the cochlea, such by using a stimulating electrode and a grounding electrode and / or by using electrodes immediately adjacent to the stimulating electrode and the grounding electrode.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0102] At block 853, a schedule of electrode stimulation and recording commands is derived. At block 855, stimulating and recording commands are provided to hardware to initiate stimulation and recording operations. At block 857, a timer initiates to trigger both stimulation operations and recording operations to initiate. At block 859, while operation of the timer is ongoing, bipolar monophasic stimulation is provided. Additionally, at block 867, electrical potential at the selected location of the cochlea is measured using the established recording electrodes.

[0103] At block 869, an individual electrical potential is recorded at a particular time indicated by the timer. In this manner, cochlear stimulation and electrical potential measurement occur in parallel (e.g., concurrently) in that electrical potential measurement occurs while stimulation is being provided. At block 861, the time increment of the timer increases. At block 863, a determination is made regarding whether the time increment of the timer indicates stimulation operations and recording operations are to be suspended. In response to a determination that the time increment of the timer does not indicate stimulation operations and recording operations are to be suspended, bipolar monophasic stimulation, as performed at block 859, and recording operations, as performed at blocks 867 and 869, continue, and the time increment of the timer continues to increase. Accordingly, electrical potential measurements at different particular time increments are repeatedly recorded to establish a timeseries of electrical potential measurements indicating a change in electrical potential over the time during which the recording operations are performed. However, in response to a determination that the time increment of the timer indicates stimulation operations and recording operations are to be suspended, bipolar monophasic stimulation, recording operations, and operation of the timer are suspended.

[0104] Afterwards, at block 875, frequency analysis is conducted on the timeseries of electrical potential measurements, such as to determine a frequency of possible oscillations of electrical potential measurements as caused by an acoustic signal. At block 877, a phase analysis is conducted between the timeseries of electrical potential measurements and the acoustic signal being delivered, such as by comparing the frequency of the oscillation of electrical potential measurements to the frequency of the acoustic signal. At block 879, a concordance between the timeseries of electrical potential measurements and the acoustic signal is determined, such as based on a difference between the frequency of the oscillation of electrical potential measurements and the frequency of the acoustic signal. At block 881, a determination is made regarding whether electrical potentials have been measured at all sections of the electrodeAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIarray. In response to a determination that electrical potentials have been measured at all sections of the electrode array, a new section of the electrode array is determined, and the method 845 is repeated for the new section. However, in response to a determination that electrical potentials have been measured at all sections of the electrode array, the method 845 is completed.

[0105] Although each of the methods 745, 845 includes performing operations for a single acoustic signal for each section of the electrode array, it should be noted that each method 745, 845 can also be performed for multiple acoustic signals for each section of the electrode array. For instance, acoustic signals having varying frequencies (e.g., of a frequency sweep) can be delivered to the cochlea, and stimulating operations, recording operations, and frequency / phase analysis can concurrently be performed to determine whether a location of the cochlea is more readily able to transmit an acoustic signal of a particular frequency (e.g., and not able to transmit an acoustic signal of a different frequency). Thus, the methods 745, 845 can be repeated for a single section of the electrode array with acoustic signals before being performed for a new section of the electrode array.

[0106] As previously described, the technology disclosed herein can be applied in any of a variety of circumstances and with a variety of different devices. An example device that can benefit from technology disclosed herein is described in more detail in FIG. 9, which illustrates a tinnitus therapy device 900 (e.g., a tinnitus implant, a tinnitus management stimulator) including a sound input unit 902 (e.g., a microphone) configured to receive acoustic inputs. In some embodiments, the sound input unit 902 is implanted adjacent to an outer ear 903 to position a diaphragm 916 of the sound input unit 902 such that the diaphragm 916 is configured to be displaced (vibrate) in response to the acoustic inputs. The tinnitus therapy device 900 further includes an implant body 904 in which circuitry, such as a processor and / or a memory, is disposed. The implant body 904 is also coupled to a coil 908 to enable transfer of power / data between the tinnitus therapy device 900 and an external device. The implant body 904 is electrically coupled to the sound input unit 902 to receive the acoustic input. The tinnitus therapy device 900 is then configured to convert the acoustic input to tinnitus therapy control signals (e.g., based on a classification of the acoustic input).

[0107] The tinnitus therapy control signals are provided to an actuator 906 electrically coupled to the implant body 904 for delivery to the recipient. By way of example, a coupling member 940 couples the actuator 906 to an ossicular chain 936 (i.e., the malleus, the incus, and the stapes bones) positioned in a middle ear cavity between a tympanic membrane 913 and aAtty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIcochlea 938 of the recipient, and the actuator 906 is configured to deliver the tinnitus therapy control signals. The actuator 906 is attached to a temporal bone 915 of the recipient via a fixation system 942 and is configured to impart motion to (e.g., vibrate) the ossicular chain 936, which is typically configured to amplify sound waves received via an ear canal 911. In operation, the actuator 906 is configured to impart motion based on the tinnitus therapy control signals, and such vibration creates waves of fluid motion of perilymph within the cochlea 938 to activate hair cells within the cochlea 938. Activation of the hair cells causes nerve impulses to be generated and transferred through spiral ganglion cells, an auditory nerve, and a brain, where the vibration is perceived as sounds to provide relief of tinnitus symptoms experienced by the recipient.

[0108] Techniques discussed herein can be applied to the tinnitus therapy device 900 to operate the tinnitus therapy device 900 based on characteristics (e.g., acoustic transmission characteristics) at different locations of the cochlea 938. For example, the tinnitus therapy device 900 can be used to stimulate a location of the cochlea 938 to generate an electrical potential therein. Meanwhile, an acoustic signal is delivered to vibrate the cochlea 938. The electrical potential is monitored while the acoustic signal is being delivered, and a frequency of oscillations of the electrical potential is compared to a frequency of the acoustic signal to determine ability of the location of the cochlea 938 to transmit the acoustic signal. In response to determining the acoustic transmission characteristics of the cochlea 938 indicate a location of the cochlea 938 is more readily able to transmit sounds of a particular frequency, operation of the tinnitus therapy device 900 can be adjusted / established to stimulate the location of the cochlea 938 to perceive sounds of that particular frequency. As a result, the tinnitus therapy device 900 can help the recipient perceive sound more suitably (e.g., clearly) and can therefore operate more effectively to provide relief of tinnitus symptoms experienced by the recipient.

[0109] It is to be appreciated that FIG. 9 is merely illustrative of devices / sy stems that can implement aspects of the techniques presented herein. In other embodiments, the techniques presented herein can be implemented in / by / with sleep disorder devices (e.g., sleep apnea devices), seizure devices (e.g., devices for monitoring and / or treating epileptic events), balance or movement disorder devices (e.g., vestibular stimulation devices), other tinnitus management devices, visual implants (e.g., bionic eyes) and other neuromodulation devices (e.g., braincomputer interfaces). For example, these different devices can be configured to generate electrical potentials at one or more locations in a recipient (e.g., in an inner ear or fluid-filled body chamber / cavity). In accordance with such embodiments, the corresponding device (e.g.,Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIthe sleep disorder device, seizure devices, balance or movement disorder device, tinnitus management device, visual implant, and / or another neuromodulation device) or another device (e.g., external device, associated computing device, etc.) delivers an input signal to vibrate the fluid at the one or more locations (e.g., the fluid in the body chamber). In turn, the corresponding device monitors / captures / measures / records / obtains the electrical potential responsive to delivery of the input signal. The corresponding device (e.g., the sleep disorder device, seizure devices, balance or movement disorder device, tinnitus management device, visual implant, and / or another neuromodulation device) or another device (e.g., external device, associated computing device, etc.) evaluate s / analyzes one or more characteristics of the body chamber based on the electrical potential.[oono] Although the above examples are primarily described with respect to evaluating acoustic transmission characteristics of a cochlea based on electrical potential, it should be noted that the techniques can be performed to evaluate other characteristics, such as blood viscosity. For example, electrodes of a stent and / or of a deep brain stimulator can be used to generate an electrical potential and measure the electrical potential to measure the other characteristics.[oom] FIG. 10 is a block diagram illustrating one example arrangement for a computing device 1000 configured to perform one or more operations in accordance with certain embodiments presented herein. As shown in FIG. 10, in its most basic configuration, the computing device 1000 includes at least one processing unit 1083 and a memory 1084. The processing unit 1083 includes one or more hardware or software processors (e.g., Central Processing Units) that can obtain and execute instructions. The processing unit 1083 can communicate with and control the performance of other components of the computing device 1000. The memory 1084 is one or more software or hardware-based computer-readable storage media operable to store information accessible by the processing unit 1083. The memory 1084 can store, among other things, instructions executable by the processing unit 1083 to implement applications or cause performance of operations described herein, as well as other data. The memory 1084 can be volatile memory (e.g., RAM), non-volatile memory (e.g., ROM), or combinations thereof. The memory 1084 can include transitory memory or non-transitory memory. The memory 1084 can also include one or more removable or non-removable storage devices. In examples, the memory 1084 can include RAM, ROM) EEPROM (Electronically-Erasable Programmable Read-Only Memory), flash memory, optical disc storage, magnetic storage, solid state storage, or any other memory media usable to store information for later access. By way of example,Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIand not limitation, the memory 1084 can include wired media, such as a wired network or direct-wired connection, and wireless media, such as acoustic, RF, infrared, other wireless media, or combinations thereof. In certain embodiments, the memory 1084 comprises logic 1095 that, when executed, enables the processing unit 1083 to perform aspects of the techniques presented. For example, logic 1095 could be executed to analyze electrical potential measurements obtained from a body chamber of a recipient and, accordingly, characterize / evaluate one or more characteristics of the body chamber, as described in greater detail elsewhere herein.

[0112] In the illustrated example of FIG. 10, the computing device 1000 further includes a network adapter 1086, one or more input devices 1087, and one or more output devices 1088. The computing device 1000 can include other components, such as a system bus, component interfaces, a graphics system, a power source (e.g., a battery), among other components. The network adapter 1086 is a component of the computing device 1000 that provides network access (e.g., access to at least one network 1089). The network adapter 1086 can provide wired or wireless network access and can support one or more of a variety of communication technologies and protocols, such as Ethernet, cellular, Bluetooth, near-field communication, and RF, among others. The network adapter 1086 can include one or more antennas and associated components configured for wireless communication according to one or more wireless communication technologies and protocols. The one or more input devices 1087 are devices over which the computing device 1000 receives input from a user. The one or more input devices 1087 can include physically-actuatable user-interface elements (e.g., buttons, switches, or dials), a keypad, keyboard, mouse, touchscreen, and voice input devices, among other input devices that can accept user input. The one or more output devices 1088 are devices by which the computing device 1000 is able to provide output to a user. The output devices 1088 can include a display 1090 (e.g., a liquid crystal display (LCD)) and one or more speakers 1091, among other output devices for presentation of visual or audible information to the recipient, a clinician, an audiologist, or other user.

[0113] It is to be appreciated that the arrangement for the computing device 1000 shown in FIG. 10 is merely illustrative and that aspects of the techniques presented herein can be implemented at a number of different types of systems / devices including any combination of hardware, software, and / or firmware configured to perform the functions described herein. For example, the computing device 1000 can be a personal computer (e.g., a desktop or laptop computer), a hand-held device (e.g., a tablet computer), a mobile device (e.g., a smartphone),Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCIa surgical system, and / or any other electronic device having the capabilities to perform the associated operations described elsewhere herein.

[0114] As should be appreciated, while particular uses of the technology have been illustrated and discussed above, the disclosed technology can be used with a variety of devices in accordance with many examples of the technology. The above discussion is not meant to suggest that the disclosed technology is only suitable for implementation within systems akin to that illustrated in the figures. In general, additional configurations can be used to practice the processes and systems herein and / or some aspects described can be excluded without departing from the processes and systems disclosed herein.

[0115] This disclosure described some aspects of the present technology with reference to the accompanying drawings, in which only some of the possible aspects were shown. Other aspects can, however, be embodied in many different forms and should not be construed as limited to the aspects set forth herein. Rather, these aspects were provided so that this disclosure was thorough and complete and fully conveyed the scope of the possible aspects to those skilled in the art.

[0116] As should be appreciated, the various aspects (e.g., portions, components, etc.) described with respect to the figures herein are not intended to limit the systems and processes to the particular aspects described. Accordingly, additional configurations can be used to practice the methods and systems herein and / or some aspects described can be excluded without departing from the methods and systems disclosed herein.

[0117] According to certain aspects, systems and non-transitory computer readable storage media are provided. The systems are configured with hardware configured to execute operations analogous to the methods of the present disclosure. The one or more non-transitory computer readable storage media comprise instructions that, when executed by one or more processors, cause the one or more processors to execute operations analogous to the methods of the present disclosure.

[0118] Similarly, where steps of a process are disclosed, those steps are described for purposes of illustrating the present methods and systems and are not intended to limit the disclosure to a particular sequence of steps. For example, the steps can be performed in differing order, two or more steps can be performed concurrently, additional steps can be performed, and disclosed steps can be excluded without departing from the present disclosure. Further, the disclosed processes can be repeated.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI

[0119] Although specific aspects were described herein, the scope of the technology is not limited to those specific aspects. One skilled in the art will recognize other aspects or improvements that are within the scope of the present technology. Therefore, the specific structure, acts, or media are disclosed only as illustrative aspects. The scope of the technology is defined by the following claims and any equivalents therein.

[0120] It is also to be appreciated that the embodiments presented herein are not mutually exclusive and that the various embodiments can be combined with another in any of a number of different manners.

Claims

Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCICLAIMSWhat is claimed is:

1. A method, comprising:generating an electrical potential at a first location in recipient;delivering one or more acoustic signals to vibrate body fluid at the first location; contemporaneously with delivery of the one or more acoustic signals, measuring the electrical potential at the first location; andevaluating acoustic transmission characteristics of at least the first location based on the measured electrical potential at the first location.

2. The method of claim 1, wherein the first location is a cochlea of the recipient and wherein delivering the one or more acoustic signals to vibrate fluid at the first location comprises:delivering the one or more acoustic signals to vibrate perilymph at the first location in the cochlea.

3. The method of claim 1 or 2, wherein the one or more acoustic signals are delivered as part of a frequency sweep.

4. The method of claim 1 or 2, comprising:generating an electrical potential at a second location in the recipient;delivering one or more additional acoustic signals to vibrate body fluid at the second; contemporaneously with delivery of the one or more additional acoustic signals, measuring the electrical potential at the second location; andevaluating acoustic transmission characteristics of at least the second location based on the measured electrical potential at the first location and at the second location.

5. The method of claim 1 or 2, wherein generating the electrical potential at the first location comprises:delivering at least one monophasic stimulation signal to the recipient at the first location.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI6. The method of claim 1 or 2, wherein delivering at least one monophasic stimulation signal to the recipient at the first location comprises:sourcing current via a first electrode implanted in the recipient; andsinking the current at a second electrode implanted in the recipient.

7. The method of claim 6, wherein at least one of the first electrode or the second electrode is implanted in the recipient proximate to the first location.

8. The method of claim 7, wherein both the first electrode and the second electrode are implanted in the recipient proximate to the first location.

9. The method of claim 7, wherein the first electrode and the second electrode are part of an electrode array implanted in the recipient, and wherein the first electrode and the second electrode are adjacent electrodes of the electrode array.

10. The method of claim 7, wherein the first electrode and the second electrode are part of an electrode array implanted in the recipient, and wherein the first electrode and the second electrode are separated by one or more other electrodes of the electrode array.

11. The method of claim 6, comprising:after measuring the electrical potential at the first location, delivering a charge balancing pulse to the recipient or short circuiting the first and second electrodes.

12. The method of claim 1 or 2, wherein a plurality of electrodes is implanted in the recipient, and wherein evaluating acoustic transmission characteristics of at least the first location based on the measured electrical potential at the first location comprises:correlating acoustic frequencies and electrode location within the recipient.

13. The method of claim 1 or 2, wherein a plurality of electrodes is implanted in the recipient, and wherein evaluating acoustic transmission characteristics of at least the first location based on the measured electrical potential at the first location comprises:determining a frequency allocation table for the plurality of electrodes.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI14. The method of claim 1 or 2, wherein evaluating acoustic transmission characteristics of at least the first location based on the measured electrical potential at the first location comprises:characterizing an amount of fibrosis at the first location.

15. The method of claim 1 or 2, further comprising:suppressing nerve activity by the recipient prior to measuring the electrical potential at the first location.

16. The method of claim 15, wherein suppressing nerve activity comprises at least one of:performing forward masking or applying an anesthetic to the recipient.

17. A system, comprising:a stimulating assembly configured to be implanted in a recipient and to generate an electrical potential at a location of a cochlea of the recipient;an acoustic source configured to deliver an acoustic signal to vibrate the cochlea; and a processor configured to monitor the electrical potential at the location following delivery of the acoustic signal to the cochlea.

18. The system of claim 17, wherein the processor is configured to monitor changes in the electrical potential at the location caused by vibration induced by delivery of the acoustic signal to the cochlea.

19. The system of claim 17, further comprising:at least one electrode disposed proximate to the location; andat least one amplifier circuit configured to capture electrical potential measurements via the at least one electrode,wherein the processor is configured to use the electrical potential measurements to monitor the electrical potential at the location.

20. The system of claim 17, 18, or 19, wherein the processor is configured to measure the electrical potential at the location based on a potential difference between at least a pair of electrodes of the stimulating assembly.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI21. The system of claim 20, wherein the stimulating assembly comprises a first electrode and a second electrode, and wherein the stimulating assembly is configured to generate the electrical potential at the location of the cochlea by sourcing current at the first electrode and sinking current at the second electrode.

22. The system of claim 21, wherein the pair of electrodes of the stimulating assembly used by the processor to measure the electrical potential at the location comprises the first electrode and the second electrode.

23. The system of claim 21, wherein the stimulating assembly comprises an intermediate electrode immediately adjacent to each of the first electrode and the second electrode, and the pair of electrodes used by the processor to measure the electrical potential at the location comprises the intermediate electrode.

24. The system of claim 21, wherein the stimulating assembly comprises a first outer electrode immediately adjacent to the first electrode and a second outer electrode immediately adjacent to the second electrode, and the pair of electrodes used by the processor to measure the electrical potential at the location comprises at least one of the first outer electrode or the second outer electrode.

25. The system of claim 20, wherein the processor is configured to determine a frequency allocation table for the stimulating assembly based on the electrical potential.

26. The use of the system according to any one of claims 17, 18, 19, 20, 21, 22, 23, 24, or 25 in a tinnitus management system.

27. The system according to any one of claims 17, 18, 19, 20, 21, 22, 23, 24, or 25, wherein the system is a tinnitus management system.

28. A method, comprising:generating an electrical potential within fluid of a body chamber of a recipient; delivering an input signal to vibrate the fluid in the body chamber;monitoring the electrical potential responsive to delivery of the input signal; and determining one or more characteristics of the body chamber based on the electrical potential.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI29. The method of claim 28, wherein determining one or more characteristics of the body chamber comprises:determining an acoustic transmission characteristic of the body chamber based on the electrical potential.

30. The method of claim 29, wherein determining the acoustic transmission characteristic of the body chamber comprises comparing a first frequency of the electrical potential to a second frequency of the input signal.

31. The method of claim 29, wherein generating the electrical potential within the fluid of the body chamber comprises:delivering one or more current signals to the body chamber.

32. The method of claim 31, wherein delivering one or more current signals to the body chamber comprises:delivering the one or more current signals via a stimulating assembly implanted in the body chamber.

33. The method of claim 31, wherein delivering one or more current signals to the body chamber comprises:delivering the one or more current signals via one or more electrodes adjacent to the body chamber.

34. The method of claim 29, wherein the electrical potential is measured as a potential difference between at least a pair of electrodes.

35. The method of claim 29, wherein determining the acoustic transmission characteristic of the body chamber based on the electrical potential includes:determining a frequency of a change to the electrical potential induced by the delivery of the input signal to the body chamber; anddetermining the acoustic transmission characteristic of the body chamber based on a comparison between the frequency of the change to the electrical potential and a frequency of the input signal.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI36. The method of claim 35, wherein the electrical potential is generated at a first location of the body chamber, and wherein the method comprises:correlating the frequency of the electrical potential with the first location in response to a difference between the frequency of the electrical potential and the frequency of the input signal being below a threshold.

37. The method of claim 29, wherein a plurality of electrodes is implanted in the body chamber, and wherein determining the acoustic transmission characteristic of the body chamber comprises:correlating acoustic frequencies and electrode location within the body chamber.

38. The method of claim 29, wherein a plurality of electrodes is implanted in the body chamber, and wherein determining the acoustic transmission characteristic of the body chamber comprises:determining a frequency allocation table for the plurality of electrodes.

39. The method of claim 29, wherein determining the acoustic transmission characteristic of the body chamber comprises:characterizing an amount of fibrosis at one or more locations of the body chamber.

40. The method of claim 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or 39, wherein delivering the input signal to vibrate the fluid in the body chamber comprises:delivering one or more acoustic signals to vibrate the fluid in the body chamber.

41. The method of claim 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or 39, wherein delivering one or more acoustic signals to vibrate the fluid in the body chamber comprises:delivering a plurality of acoustic signals as part of a frequency sweep.

42. The method of claim 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or 39, wherein generating the electrical potential within the fluid of the body chamber comprises:delivering at least one monophasic stimulation signal to the body chamber at a first location.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI43. The method of claim 42, wherein delivering at least one monophasic stimulation signal to the body chamber a at the first location comprises:sourcing current via a first electrode configured to be implanted in the recipient; and sinking the current at a second electrode configured to implanted in the recipient.

44. The method of claim 43, wherein at least one of the first electrode or the second electrode is implanted in the body chamber proximate to the first location.

45. The method of claim 43, wherein both the first electrode and the second electrode are implanted in the body chamber proximate to the first location.

46. The method of claim 43, wherein the first electrode and the second electrode are part of an electrode array implanted in the body chamber, and wherein the first electrode and the second electrode are adjacent electrodes of the electrode array.

47. The method of claim 43, wherein the first electrode and the second electrode are part of an electrode array implanted in the body chamber, and wherein the first electrode and the second electrode are separated by one or more other electrodes of the electrode array.

48. The method of claim 43, comprising:after monitoring the electrical potential, delivering a charge balancing pulse to the body chamber or short circuiting the first and second electrodes.

49. The method of claim 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or 39, further comprising:suppressing nerve activity by the recipient prior to monitoring the electrical potential.

50. The method of claim 49, wherein suppressing nerve activity comprises at least one of:performing forward masking or applying an anesthetic to the recipient.

51. The use of a system according to any one of claims 28-50 in a sleep disorder system, a seizure system, a balance or movement disorder system, a tinnitus management system, a hearing device system, or a visual system.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI52. One or more non-transitory computer readable storage media comprising instructions that, when executed by one or more processors, cause the one or more processors to:generate an electrical potential within fluid of a body chamber of a recipient, wherein the electrical potential is generated at a first location on the body chamber;vibrate the fluid in the body chamber;contemporaneously with vibration of the fluid, monitor the electrical potential at the first location; anddetermine or more characteristics of the body chamber based on the monitoring of the electrical potential.

53. The one or more non-transitory computer readable storage media of claim 52, wherein the instructions to vibrate the fluid in the body chamber comprise instructions that, when executed by the one or more processors, cause the one or more processors to:deliver one or more acoustic signals to the body chamber.

54. The one or more non-transitory computer readable storage media of claim 53, wherein the one or more acoustic signals are delivered as part of a frequency sweep.

55. The one or more non-transitory computer readable storage media of claim 52, 53, or 54, wherein the instructions to generate the electrical potential at the first location comprise instructions that, when executed by the one or more processors, cause the one or more processors to:deliver at least one monophasic stimulation signal to the body chamber.

56. The one or more non-transitory computer readable storage media of claim 52, 53, or 54, wherein determining one or more characteristics of the body chamber comprises:determining at least one acoustic transmission characteristic of the body chamber based on the electrical potential.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI57. A system, comprising:one or more electrodes configured to generate electrical potential at a location of a body chamber of a recipient;an acoustic source configured to deliver one or more acoustic signals to vibrate fluid in the body chamber;at least one electrode disposed proximate to the location;at least one amplifier circuit configured to capture electrical potential measurements via the at least one electrode; anda processor configured to use the electrical potential measurements to monitor the electrical potential at the location, and to determine at least one characteristic of the body chamber based on the monitoring of the electrical potential.

58. The system of claim 57, wherein the processor is configured to monitor changes in the electrical potential at the location caused by vibration induced by delivery of the acoustic signal to a cochlea.

59. The system of claim 57 or 58, wherein the processor is configured to measure the electrical potential at the location based on a potential difference between at least a pair of electrodes of the one or more electrodes.

60. The system of claim 59, wherein the one or more electrodes comprise a first electrode and a second electrode, and wherein the one or more electrodes are configured to generate the electrical potential at the location of the cochlea by sourcing current at the first electrode and sinking current at the second electrode.

61. The system of claim 60, wherein the pair of electrodes of the one or more electrodes used by the processor to measure the electrical potential at the location comprises the first electrode and the second electrode.

62. The system of claim 60, wherein the one or more electrodes comprise an intermediate electrode immediately adjacent to each of the first electrode and the second electrode, and the pair of electrodes used by the processor to measure the electrical potential at the location comprises the intermediate electrode.Atty. Docket No. 3065.0874i Client Ref. No. CID04075 WOPCI63. The system of claim 60, wherein the one or more electrodes comprise a first outer electrode immediately adjacent to the first electrode and a second outer electrode immediately adjacent to the second electrode, and the pair of electrodes used by the processor to measure the electrical potential at the location comprises at least one of the first outer electrode or the second outer electrode.

64. The system of claim 59, wherein the processor is configured to determine a frequency allocation table for the one or more electrodes based on the electrical potential.

65. The system according to any one of claims 57-64, wherein the system is a sleep disorder system, a seizure system, a balance or movement disorder system, a tinnitus management system, a hearing device system, or a visual system.

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