Personalized neural health condition-based stimulation

Abstract

Techniques for determination and use of neural health maps are presented herein. As used herein, a neural health map refers to a mapping that indicates neural health conditions of neurons within different regions of a neuron group. A neurological health condition indicated in / by the neurological health map indicates the ability of the neuron to respond to the stimulus. Thus, the neural health map may indicate whether a particular region of the neuron group provides a normal response to a stimulus, provides a reduced response to a stimulus, does not provide a response to a stimulus (i.e., neuronal death), etc.

Description

background Technical Field

[0002] The present invention generally relates to techniques for determining the health of neurons and their application to neuronal stimulation. Background Art

[0003] Medical devices have provided a wide range of therapeutic benefits to recipients over the last several decades. Medical devices may include internal or implantable components / devices, external or wearable components / devices, or combinations thereof (e.g., devices having external components that communicate with implantable components). Medical devices, such as traditional hearing aids, partially or fully implantable hearing prostheses (e.g., bone conduction devices, mechanical stimulators, cochlear implants, etc.), pacemakers, defibrillators, functional electrical stimulation devices, and other medical devices, have been successful over the years in performing life-saving and / or lifestyle-improving functions and / or recipient monitoring.

[0004] Over the years, the types of medical devices and the range of functions performed by them have increased. For example, many medical devices, sometimes referred to as "implantable medical devices," now typically include one or more instruments, devices, sensors, processors, controllers, or other functional mechanical or electrical components that are permanently or temporarily implanted in a recipient's body. These functional devices are typically used to diagnose, prevent, monitor, treat, or manage disease / injury or its symptoms, or to study, replace, or modify anatomical structures or physiological processes. Many of these functional devices utilize power and / or data received from an external device that is part of or operates in conjunction with the implantable component. Summary of the invention

[0005] In some aspects, the technology described herein relates to a method comprising: determining, for each electrode of a plurality of electrodes, a distance between each electrode of the plurality of electrodes and one or more neurons; determining a stimulation threshold for each electrode of the plurality of electrodes to induce a response in the one or more neurons; correlating the stimulation threshold for each electrode of the plurality of electrodes with the distance between each electrode of the plurality of electrodes and the one or more neurons; and generating a neural health map of the one or more neurons based on correlating the stimulation threshold for each electrode of the plurality of electrodes with the distance between each electrode of the plurality of electrodes and the one or more neurons.

[0006] According to other aspects, the technology described herein relates to a method comprising: determining a neural health map of a plurality of neurons stimulated by a plurality of electrodes; determining stimulation characteristics of the plurality of neurons based on the neural health map; and stimulating the plurality of neurons through the plurality of electrodes based on the stimulation characteristics.

[0007] According to yet other aspects, the technology described herein relates to a method comprising: determining a neural health map of multiple neurons stimulated by multiple electrodes; determining sound processing characteristics based on the neural health map; and processing an audio signal based on the sound processing characteristics to generate stimulation signals for the multiple electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Embodiments of the present invention are described herein with reference to the accompanying drawings, in which:

[0009] Figure 1A is a schematic diagram illustrating a cochlear implant system with which aspects of the technology presented herein may be implemented;

[0010] Figure 1B Yes Wear Figure 1A A side view of a recipient of a sound processing unit of a cochlear implant system;

[0011] Figure 1C yes Figure 1A A schematic diagram of components of a cochlear implant system;

[0012] Figure 1D yes Figure 1A Block diagram of a cochlear implant system;

[0013] Figure 2 is a schematic diagram showing a first arrangement of electrodes and neurons of the neural health map determination technique presented herein;

[0014] Figure 3 is a schematic diagram illustrating a second arrangement of electrodes and neurons of the neural health map determination technique presented herein;

[0015] Figure 4 is a schematic diagram illustrating a third arrangement of electrodes and neurons for the neural health map determination technique presented herein;

[0016] Figure 5 is a flow chart illustrating a process flow for implementing the neural health map determination techniques presented herein;

[0017] Figure 6 is a schematic diagram illustrating a neural health map determined by the neural health map determination technique presented herein;

[0018] Figure 7 is a flow chart showing a generalized process for determining neuron stimulation characteristics based on a neuron health map;

[0019] Figure 8 is a flow chart illustrating a specific exemplary embodiment of a process flow for determining neuron stimulation characteristics based on a neural health map;

[0020] Fig. 9is a comparison of audio signals and neuron excitation energies to which the neuron excitation characteristics determination technique presented in this paper can be applied;

[0021] Fig.10 is a functional block of an audio signal processing chain to which the audio signal processing characteristic determination technique presented in this article can be applied;

[0022] Fig.11 is a functional block of a warped filter bank to which the audio signal processing characteristic determination technique presented in this paper can be applied;

[0023] Fig.12 is a flow chart showing a generalized process flow for determining audio signal processing characteristics based on a neural health map;

[0024] Fig.13 is a schematic diagram illustrating an implantable stimulator system with which aspects of the technology presented herein may be implemented;

[0025] Fig.14 A schematic diagram illustrating a vestibular stimulator system with which aspects of the technology presented herein may be implemented;

[0026] Fig.15 is a schematic diagram illustrating a retinal prosthesis system with which aspects of the technology presented herein may be implemented; and

[0027] Fig.16 is a schematic diagram illustrating a computing system with which aspects of the techniques presented herein may be implemented. DETAILED DESCRIPTION

[0028] Techniques for determining and using neural health maps are presented herein. As used herein, a neural health map refers to a map that indicates the neural health of neurons in different regions of a neuron group. The neural health indicated in / by the neural health map indicates the ability of the neuron to respond to a stimulus. Thus, a neural health map can indicate whether a particular region of a neuron group provides a normal response to a stimulus, provides a reduced response to a stimulus, does not provide a response to a stimulus (i.e., neuronal death), etc.

[0029] Determining the response of a neuron group (e.g., a nerve, such as the auditory nerve) to stimulation has been addressed in conventional systems, but with limited success. Typically, after surgical implantation of a neurostimulator (e.g., a cochlear implant, a vestibular stimulator, a retinal prosthesis, or other devices known to those skilled in the art), the stimulator is adapted or customized to meet the specific recipient needs. This involves collecting and determining patient-specific parameters, such as the threshold level (T level) and maximum comfort level (C level) for each stimulation channel.

[0030] One method of querying the performance of an implanted neurostimulator and objectively measuring patient-specific data (e.g., T-levels and C-levels) is to directly measure the response of the nerve to electrical stimulation. Directly measuring the neural response is generally referred to as electrically evoked compound action potential (ECAP) in the context of cochlear implants, which provides an objective measurement of the response of the nerve to electrical stimulation. After electrical stimulation, the neural response is caused by the superposition of a single neural response at the outside of the axonal membrane. The measured neural response is usually transmitted to an external system via a telemetry system. As a result, ECAP is measured from within the cochlea in response to various stimulation signals. The measurements performed to determine whether a neural response or ECAP has occurred are referred to herein as ECAP measurements by a general term. The minimum amount of stimulation that determines the occurrence of a neural response or ECAP is referred to herein as an ECAP threshold, or more simply as a neural response threshold. As described in more detail below, the technology disclosed herein can combine the above-mentioned objective measurements of patient-specific data with physical measurements of electrode placement to determine a neural health map of a neuron group stimulated by the electrodes of an implanted stimulator.

[0031] For ease of description only, the technology presented herein is mainly described with reference to a specific implantable medical device system, i.e., a cochlear implant system. However, it should be understood that the technology presented herein can also be partially or completely implemented by other types of implantable medical devices. For example, the technology presented herein can be implemented by other auditory prosthesis systems including one or more other types of auditory prostheses (e.g., middle ear auditory prostheses, bone conduction devices, direct sound stimulators, electroacoustic prostheses, auditory brain stimulators, combinations or variations thereof, etc.). The technology presented herein can also be implemented by proprietary tinnitus treatment devices and tinnitus treatment device systems. In other embodiments, the technology presented herein can also be implemented by vestibular devices (e.g., vestibular implants), visual devices (i.e., bionic eyes), sensors, pacemakers, drug delivery systems, defibrillators, functional electrical stimulation devices, catheters, epileptic seizure devices (e.g., devices for monitoring and / or treating epileptic events), sleep apnea devices, electroporation devices, etc., or used in combination with them.

[0032] Figures 1A-1D An exemplary cochlear implant system 102 is shown with which aspects of the technology presented herein may be implemented. The cochlear implant system 102 includes an external component 104 / implantable component 112. Figures 1A-1D In the example of a cochlear implant, the implantable component is sometimes referred to as a "cochlear implant." Figure 1A The cochlear implant 112 is shown implanted in the head 154 of the recipient, and Figure 1B is a schematic diagram of the outer member 104 worn on the head 154 of the recipient. Figure 1C is another schematic diagram of a cochlear implant system 102, and Figure 1DAdditional details of cochlear implant system 102 are shown. For ease of description, the Figures 1A-1D .

[0033] Cochlear implant system 102 includes an external component 104 configured to be attached directly or indirectly to the body of a recipient, and an implantable component 112 configured to be implanted in the body of the recipient. Figures 1A-1D In the example of , external component 104 includes a sound processing unit 106, and cochlear implant 112 includes an implantable coil 114, an implant body 134, and an elongated stimulation assembly 116 configured to be implanted in the cochlea of ​​a recipient.

[0034] exist Figures 1A-1D In the example of the present invention, the sound processing unit 106 is an outside-the-ear (OTE) sound processing unit (sometimes referred to herein as an OTE component) that is configured to send data and power to the implantable component 112. Generally speaking, the OTE sound processing unit is a component having a generally cylindrical housing 111 and configured to be magnetically coupled to the head of the recipient (e.g., including an integrated external magnet 150 configured to be magnetically coupled to an implantable magnet 152 in the implantable component 112). The OTE sound processing unit 106 also includes an integrated external (head component) coil 108 configured to be inductively coupled to the implantable coil 114.

[0035] It should be appreciated that the OTE sound processing unit 106 is merely illustrative of an external device that can operate with the implantable component 112. For example, in alternative examples, the external component can include a behind-the-ear (BTE) sound processing unit or a micro-BTE sound processing unit and a separate external component. Generally speaking, the BTE sound processing unit includes a housing that is shaped to be worn on the recipient's outer ear and connected to a separate external coil assembly via a cable, wherein the external coil assembly is configured to be magnetically coupled and inductively coupled to the implantable coil 114. It should be appreciated that alternative external components can be located in the recipient's ear canal, worn on the body, etc.

[0036] As described above, cochlear implant system 102 includes sound processing unit 106 and cochlear implant 112. However, as further described below, cochlear implant 112 can operate independently of sound processing unit 106 for at least a period of time to stimulate a recipient. For example, cochlear implant 112 can operate in a first general mode (sometimes referred to as an "external hearing mode"), in which sound processing unit 106 captures sound signals, which are then used as a basis for delivering stimulation signals to the recipient. Cochlear implant 112 can also operate in a second general mode (sometimes referred to as an "invisible hearing" mode), in which sound processing unit 106 cannot provide sound signals to cochlear implant 112 (e.g., sound processing unit 106 is not present, sound processing unit 106 is powered off, sound processing unit 106 is malfunctioning, etc.). Therefore, in the invisible hearing mode, cochlear implant 112 captures the sound signals itself via an implantable sound sensor, and then uses these sound signals as a basis for delivering stimulation signals to the recipient. Further details regarding the operation of cochlear implant 112 in the external hearing mode are provided below, followed by details regarding the operation of cochlear implant 112 in the invisible hearing mode. It should be understood that the references to the external hearing mode and the invisible hearing mode are merely illustrative, and cochlear implant 112 may also operate in alternative modes.

[0037] exist Figure 1A and 1C , a cochlear implant system 102 is shown with an external device 110 configured to implement various aspects of the presented technology. The external device 110 is a computing device, such as a computer (e.g., a laptop, a desktop computer, a tablet), a mobile phone, a remote control unit, etc. As further described below, the external device 110 includes a telephone enhancement module, as further described below, which is configured to implement various aspects of the auditory rehabilitation technology presented herein for independent telephone use. The external device 110 and the cochlear implant system 102 (e.g., an OTE sound processing unit 106 or a cochlear implant 112) communicate wirelessly via a two-way communication link 126. The two-way communication link 126 may include, for example, short-range communications, such as a Bluetooth link, a Bluetooth low energy (BLE) link, a proprietary link, etc.

[0038] Return to Figures 1A-1DIn the example of the OTE sound processing unit 106, one or more input devices are configured to receive input signals (e.g., sound or data signals). The one or more input devices include one or more sound input devices 118 (e.g., one or more external microphones, audio input ports, telecoils, etc.), one or more auxiliary input devices 128 (e.g., audio ports, such as direct audio input (DAI), data ports, such as universal serial bus (USB) ports, cable ports, etc.), and wireless transmitter / receiver (transceiver) 120 (e.g., for communicating with external devices 110). However, it should be understood that the one or more input devices may include additional types of input devices and / or fewer input devices (e.g., the wireless short-range radio transceiver 120 and / or one or more auxiliary input devices 128 may be omitted).

[0039] The OTE sound processing unit 106 also includes an external coil 108, a charging coil 130, a tightly coupled transmitter / receiver (RF transceiver) 122 (sometimes referred to as a radio frequency (RF) transceiver 122), at least one rechargeable battery 132, and an external sound processing module 124. The external sound processing module 124 may include, for example, one or more processors and a memory device (memory) including sound processing logic. The memory device may include any one or more of the following: 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 memory storage devices. The one or more processors are, for example, microprocessors or microcontrollers that execute instructions of the sound processing logic stored in the memory device.

[0040] The implantable component 112 includes an implant body (main module) 134, a lead region 136, and an intracochlear stimulation assembly 116, all configured to be implanted beneath the skin / tissue (tissue) 115 of a recipient. The implant body 134 generally includes a hermetically sealed housing 138 in which an RF interface circuit system 140 and a stimulator unit 142 are disposed. The implant body 134 also includes an internal / implantable coil 114, which is generally external to the housing 138 but is connected to the stimulator unit 142 via a hermetic feedthrough ( Figure 1D ) is connected to the RF interface circuit system 140.

[0041] As described, the stimulation assembly 116 is configured to be at least partially implanted in the cochlea of ​​a recipient. The stimulation assembly 116 includes a plurality of longitudinally spaced intracochlear electrical stimulation contacts (electrodes) 144 that collectively form a contact or electrode array 146 for delivering electrical stimulation (electrical current) to the cochlea of ​​the recipient.

[0042] The stimulation assembly 116 extends through an opening in the recipient's cochlea (e.g., a cochlear fenestration, a round window, etc.) and has a lead region 136 and an airtight feedthrough ( Figure 1D 144 is connected to the proximal end of the stimulator unit 142. The lead region 136 includes a plurality of conductors (wires) that electrically couple the electrode 144 to the stimulator unit 142. The implantable component 112 also includes an electrode outside the cochlea, sometimes referred to as an extracochlear electrode (ECE) 139.

[0043] As described, the cochlear implant system 102 includes an external coil 108 and an implantable coil 114. An external magnet 152 is fixed relative to the external coil 108, and the implantable magnet 152 is fixed relative to the implantable coil 114. The magnets fixed relative to the external coil 108 and the implantable coil 114 facilitate 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 implantable component 112 via a tightly coupled wireless link 148 formed between the external coil 108 and the implantable coil 114. In some examples, the tightly coupled wireless link 148 is a radio frequency (RF) link. However, various other types of energy transfer (e.g., infrared (IR), electromagnetic, capacitive, and inductive transfer) may be used to transfer power and / or data from the external component to the implantable component, and thus, Figure 1D Only one exemplary arrangement is shown.

[0044] As described above, the sound processing unit 106 includes an external sound processing module 124. The external sound processing module 124 is configured to convert an input signal received (received at one or more of the input devices) into an output signal for stimulating the first ear of the recipient (i.e., the external sound processing module 124 is configured to perform sound processing on the input signal received at the sound processing unit 106). In other words, the one or more processors in the external sound processing module 124 are configured to execute the sound processing logic in the memory to convert the received input signal into an output signal representing electrical stimulation for delivery to the recipient.

[0045] As referenced below Fig.10 and 11 As explained in detail, a specific exemplary embodiment of external sound processing module 124 may be configured with a warping filter bank through which application of a neural health map is implemented in cochlear implant system 102 .

[0046] As mentioned above, Figure 1DAn embodiment is shown in which an external sound processing module 124 in the sound processing unit 106 generates an output signal. In an alternative embodiment, the sound processing unit 106 can send less processed information (e.g., audio data) to the implantable component 112, and the sound processing operations (e.g., conversion of sound to output signals) can be performed by a processor within the implantable component 112.

[0047] Return to Figure 1D In a specific example, the output signal is provided to the RF transceiver 122, which transmits the output signal (e.g., in an encoded manner) transcutaneously to the implantable component 112 via the external coil 108 and the implantable coil 114. That is, the output signal is received at the RF interface circuit system 140 via the implantable coil 114 and provided to the stimulator unit 142. The stimulator unit 142 is configured to utilize the output signal to generate an electrical stimulation signal (e.g., a current signal) for delivery to the cochlea of ​​the recipient. In this way, the cochlear implant system 102 electrically stimulates the auditory nerve cells of the recipient, thereby bypassing the missing or defective hair cells that normally convert acoustic vibrations into neural activity in a manner that causes the recipient to perceive one or more components of the received sound signal.

[0048] As described in detail 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 the sound signals for electrical stimulation of the recipient's auditory nerve cells. Figure 1D As shown in , the cochlear implant 112 includes a plurality of implantable sound sensors 160 and an implantable sound processing module 158. Similar to the external sound processing module 124, the implantable sound processing module 158 may include, for example, one or more processors and a memory device (memory) including sound processing logic. The memory device may include any one or more of the following: 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 memory storage devices. The one or more processors are, for example, microprocessors or microcontrollers that execute instructions of the sound processing logic stored in the memory device.

[0049] A specific exemplary embodiment of implantable sound processing module 158 may be configured with a warp filter bank through which application of a neural health map is implemented in cochlear implant system 102, as described below with reference to Fig.10 and 11 Described in detail.

[0050] In the invisible hearing mode, the implantable sound sensor 160 is configured to detect / capture a signal (e.g., an acoustic sound signal, a vibration, etc.), which is provided to the implantable sound processing module 158. The implantable sound processing module 158 is configured to convert a received input signal (received at one or more implantable sound sensors 160) into an output signal for stimulating the first ear of the recipient (i.e., the processing module 158 is configured to perform a sound processing operation). In other words, the one or more processors in the implantable sound processing module 158 are configured to execute the sound processing logic in the memory to convert the received input signal into an output signal 156 provided to the stimulator unit 142. The stimulator unit 142 is configured to generate an electrical stimulation signal (e.g., an electric current signal) for delivery to the cochlea of ​​the recipient using the output signal 156, thereby bypassing the missing or defective hair cells that normally convert the acoustic vibrations into neural activity.

[0051] It should be understood that the above description of the so-called external hearing mode and the so-called invisible hearing mode is merely illustrative, and that the cochlear implant system 102 may operate differently in different embodiments. For example, in an alternative embodiment of the external hearing mode, the cochlear implant 112 may use the signals captured by the sound input device 118 and the implantable sound sensor 160 to generate stimulation signals for delivery to the recipient.

[0052] As described above, the present invention is presented herein for use in accordance with components (e.g., Figure 1D The present invention relates to a technique for determining and using a neural health map using objective measurements obtained / captured by an electrode assembly 146 of a neurostimulator. In some embodiments, these objective measurements are combined with physical measurements of electrode placement to determine the neural health of neurons stimulated by a neurostimulator.

[0053] Reference now Figure 2 , depicted herein is a series of electrodes 205a-e arranged relative to a group 210 of neurons (e.g., neurons arranged around the modiolus of the cochlea). As explained below, the distances 220a-e between the electrodes 205a-e and the neurons 210 are obtained from physical measurements of the electrode placement, such as computed tomography (CT), x-ray, or magnetic resonance imaging of the electrodes.

[0054] Additional techniques for determining electrode placement may include electrode voltage tomography (EVT) techniques. According to certain EVT techniques, an EVT measurement includes a plurality of sequential measurement sets, each of which involves one of the intracochlear electrodes of a cochlear implant (e.g., Figure 1D The electrodes 144 of the implant are connected to the extra-cochlear electrodes (e.g., Figure 1DCurrent delivery between the extracochlear electrodes 139). With each delivery of current between one of the intracochlear electrodes and the extracochlear electrode, a voltage measurement is obtained between the extracochlear electrode and each of the other intracochlear electrodes. This process can be repeated for one or more (or all) of the other intracochlear electrodes that serve as current delivery electrodes. Based on the measurements obtained, the placement or distance of the electrode relative to the neuron can be determined. The EVT measurements can be stored in a matrix called a transimpedance matrix (TIM). The values ​​of the TIM characterize the electrical properties of the electrode and the tissue surrounding the electrode assembly.

[0055] To determine the stimulus components (e.g. Figure 1D The TIM of each electrode of the electrode assembly 146 of the stimulating electrode assembly is calculated by applying a current i to the first electrode at a known current level and recording / measuring the resulting voltage v at all other electrodes. The transimpedance z of each combination of the stimulating electrode and the recording electrode is calculated as shown in Equation 1 below:

[0056] z i,j =v i / i j , (1)

[0058] where v i is the voltage measured at the recording electrode, i j is the current delivered at the stimulation electrode, z i,j is the transimpedance measured therebetween. The calculated transimpedances of all electrode pairs are combined to form a full transimpedance matrix (Z). For a 22-electrode assembly, the result is a 22x22 transimpedance matrix. The values ​​stored in the TIM can be used to determine the positioning of the electrodes relative to the neurons of the cochlea.

[0059] Regardless of the method used to determine the distances 220a-e, the techniques of the present disclosure relate the distances 220a-e to the stimulation signals (stimuli) 215a-e necessary to induce a response in the neuron group 210 in the regions 225a-e, respectively. For purposes of the present disclosure, the graphical magnitudes of the stimulation signals 215a-e (represented by the shaded areas) generally indicate the stimulation levels / thresholds necessary to induce a response in the neuron group 210 within the regions 225a-e, respectively.

[0060] exist Figure 2 In the example of FIG. 1 , the correlation between distances 220a-e and stimulation signals 215a-e can be used to determine the neural health status within regions 225a-e, respectively. More specifically, Figure 2 The electrodes 205a-e are shown to be all relatively equally spaced from the neuron group 210. Thus, the distances 220a-e are all of similar magnitude. Figure 2Also shown are the intensities of the stimulation signals 215a-e used to induce responses, which are also relatively equal, as indicated by the illustrated magnitudes of the stimulation signals 215a-e. Therefore, because the distances 220a-e between the electrodes 205a-e and the neuron group 210 are relatively equal, respectively, and the magnitudes of the stimulation signals 215a-e required to induce responses in the neuron group 210 in the regions 225a-e are relatively the same, it can be inferred that the regions 225a-e share similar neural health levels. Moreover, because both the estimated distances 220a-e from the electrodes 205a-e to the neuron group 210 and the stimulation signals 215a-e are low, it is determined that all neurons within the regions 225a-e have good neural health levels. Therefore, a neural health map of the regions 225a-e can be determined, in which all regions have normal neural health levels.

[0061] Go to Figure 3 , where electrodes 305a-e and neuron group 310 are shown, similar to Figure 2 Electrodes 205a-e and neuron group 210. Similar to Figure 2 , the distances 320a-e between electrodes 305a-e and neurons 310 are obtained from physical measurements. The graphical magnitudes of stimulation signals 315a-e (represented by shaded areas) generally indicate the stimulation levels required to induce a response in neuronal group 310 within regions 325a-e, respectively.

[0062] As shown, the distances 320a, 320b, 320d and 320e between electrodes 305a, 305b, 305d and 305e and neuron group 310 are substantially the same, but electrode 305c is substantially further away from neuron group 310. In addition, the magnitude of the stimulation signal 315c necessary to induce a response in region 325c is similarly greater than the magnitude of the stimulation signal 315a, 315b, 315d and 315e. However, the increase in the magnitude of the stimulation 315c does not indicate that the health of the neurons arranged in region 325c is poor. In fact, by correlating the distance with the stimulation level / threshold, it is determined that the stimulation required to increase for electrode 305c is to induce a response in region 325c because the distance 320c is greater than the distance 320a, 320b, 320d and 320e, rather than because the neural health in region 325c is reduced. Therefore, a neural health map of regions 325a-e can be determined, in which all regions have normal neural health levels.

[0063] exist Figure 2 and 3, a monotonic relationship between the distance of the electrodes 215a-e, 305a-e from the neuron groups 210, 310 and the stimulation signal 215a-e, 315a-e required to induce a response in the regions 225a-e, 325a-e is shown. As the distance between the electrodes 215a-e, 305a-e and the neuron groups 210, 310 decreases, the magnitude of the stimulation required to induce a response also decreases. As the distance 220a-e, 320a-e between the electrodes 215a-e, 305a-e and the regions 225a-e, 325a-e increases, the magnitude of the stimulation required to induce a response also increases. Thus, a large stimulation 315c associated with electrode 305c does not indicate poor neural health within region 325c because the distance 320c is also correspondingly larger. Turning to Figure 4 , large stimulation 415c of electrode 405c, on the other hand, indicates poor nerve health.

[0064] More specifically, Figure 4 Electrodes 405a-e and neuron group 410 are shown, similar to Figure 2 Electrodes 205a-e and neuron group 210. Similar to Figure 2 , the distances 420a-e between electrodes 405a-e and neurons 410 are obtained from physical measurements. The illustrated magnitudes of stimulation signals 415a-e (represented by shaded areas) generally indicate the stimulation levels required to induce a response in neuronal group 410 within regions 425a-e, respectively.

[0065] Stimulation signal 415c is associated with a larger magnitude of stimulation that induces a response in neuron group 410 in region 425c (as indicated by the larger magnitude of shaded region 415c). Because distance 420c is not significantly greater than distances 420a, 420b, 420d, and 420e, but the magnitude of stimulation signal 415c is significantly greater than the magnitudes of stimulation signals 415a, 415b, 415d, and 415e, the magnitude of stimulation signal 415c actually indicates that the neuron health in region 425c is poor. Similarly, if stimulation signal 415c increases without detecting any response from region 425c, this can be used as an indication of neuron death within region 425c. Therefore, a neural health map of regions 425a-e can be determined, where regions 425a, 425b, 425d, and 425e have normal neural health levels and region 425c has poor neural health levels.

[0066] Reference now Figure 5, depicted therein is a flowchart 500 illustrating a generalized process for determining a neural health map according to the techniques disclosed herein. Flowchart 500 begins at operation 505, where a distance from each of a plurality of electrodes to one or more neurons is determined, wherein the plurality of electrodes may include all electrodes implanted in a recipient or only a subset of the electrodes (e.g., a set of two electrodes, a set of three electrodes, etc.). Thus, operation 505 may be a process by which the distances 220a-e, 320a-e, and / or 420a-e are determined. For example, CT imaging, x-ray imaging, or magnetic resonance imaging may be used to determine the distances of an electrode array (e.g., Figure 1D The positioning of each electrode in the electrode assembly 146 relative to the neuron that the electrode is intended to stimulate. Other methods of determining the positioning of one or more electrodes may also be used, such as the EVT / TIM technique described above.

[0067] Next, in operation 510, for each of the plurality of electrodes, a threshold for eliciting a response in one or more neurons is determined. For example, operation 510 may include a process by which the magnitude of stimulation signals 215a-e, 315a-e, and / or 415a-e is determined. For a cochlear implant recipient, operation 510 may be embodied as determining a neural response threshold for each of the plurality of electrodes of the implant. Specifically, telemetry software may be used in conjunction with the plurality of electrodes to calculate a neural response threshold for each electrode. For other types of neurons (e.g., as described below with reference to Figure 13-15 Operation 510 may determine different types of thresholds, so long as the determined threshold is a threshold that correlates a stimulation level with eliciting a response in one or more neurons.

[0068] According to one specific example of calculating a neural response threshold in operation 510, software with a built-in algorithm can be used that marks the negative and positive peaks of the ECAP from the auditory nerve of the cochlear implant recipient, the software calculates the peak-to-peak magnitude difference, and then plots the difference as a function of the current level. This plot is called an amplitude growth function or an input-output function. The neural response threshold is derived from a linear regression applied to the data points in the growth function.

[0069] Monopolar stimulation may be used in operation 510 to determine a neural response threshold for a region of neurons. However, the techniques disclosed herein are not limited to monopolar stimulation only. Bipolar, tripolar, or focused multipolar stimulation techniques may be used to generate a more focused electric field. Thus, bipolar, tripolar, or focused multipolar stimulation techniques may be used to generate a more detailed neural health map.

[0070] To determine the neural health of the area between electrodes, virtual channel stimulation techniques can be used. According to these techniques, the absolute and relative ratios of the currents of virtual channels (e.g., a pair of adjacent electrodes that are activated simultaneously) can be adjusted to produce inter-electrode stimulation placement in the cochlea. Figure 2 , virtual channel technology can be used to determine the neural health of regions 230a-d.

[0071] return Figure 5 In operation 515, the threshold of each electrode in the plurality of electrodes is correlated with the distance between each electrode in the plurality of electrodes and one or more neurons. Figure 2-4 As described, the relationship between the distance from the electrode to the neuron and the amount of stimulation required to excite the neuron can indicate the neural health. Correlating the distance between the electrode and the neuron with a threshold allows determining the neural health of the neuron stimulated by each of the plurality of electrodes.

[0072] Finally, in operation 520, a neural health map of one or more neurons is generated based on the correlations that occurred in operation 515. Figure 2-4 As an example, the neural health map for regions 225a-e, 325a-e, and 425a-e would indicate good neural health in regions 225a-e, 325a-e, 425a, 425b, 425d, and 425e, and poor neural health or neuronal death in region 425c.

[0073] Reference now Figure 6 , which depicts a neural health map 600 of a cochlea 640, the neural health of which has been mapped according to the techniques disclosed herein. Figure 6 The modiolar wall 620 (e.g., the wall of the scala tympani 608 adjacent to the modiolar axis 612) and the lateral wall 618 (e.g., the wall of the scala tympani 608 located opposite the modiolar axis 612) are shown in FIG. Figure 6 Also shown is a cochlear opening 642, which may be, for example, a natural opening (e.g., a round window) or a surgical opening (e.g., a cochleostomy). The cochlea 640 includes a map of its neurological health in the form of regions 625a-e. As shown by its shading, region 625c has been mapped as having poor neurological health, while regions 625a, 625b, 625d, and 625e have been mapped as having good neurological health.

[0074] The neural health map 600 will allow control of a stimulation unit of an implantable medical device (e.g. Figure 1D Stimulation unit 142) and electrode array (e.g. Figure 1DThe electrode array 146 of the cochlea 640 can be adjusted to address the specific neural health needs of the cochlea 640. For example, by using the neural health map 600 and additional information (e.g., TIM), stimulation parameters can be adjusted to compensate for various limitations in the electrode-neuron interface. The adjusted stimulation parameters can include, for example, the degree of focus of the focused multipolar stimulation (also referred to herein as the defocus index (DI)) and / or the assumed excitation spread. These techniques can be used to define other stimulation parameters, such as current manipulation, number of activated electrodes, stimulation rate, and other parameters known to those skilled in the art. The selection process for these parameters can include objective metrics, which can be performed intraoperatively on a personalized first trial fit map.

[0075] Reference now Figure 7 , which depicts the neural health map (e.g., reference above Figure 2-6 Flowchart 700 of a method for determining a neural health map (determined based on the description) applied to stimulation characteristics of an implanted medical device. Flowchart 700 begins at operation 705, where a neural health map of a plurality of neurons stimulated by a plurality of electrodes (e.g., all or only a subset of the electrodes implanted in a recipient) is determined. According to a specific exemplary embodiment, the determination of operation 705 may be based on correlating the stimulation necessary to induce a response in the electrode with the distance between the electrode and the neuron. According to other exemplary embodiments, the neural health map of operation 705 may be determined by other techniques known to those skilled in the art. For example, the neural health may be determined by other techniques such as the slope of the ECAP amplitude growth function (AGF), the effect of interphase gap (IPG) changes on the AGF curve, the spread of excitation (SOE) measurement using panoramic ECAP (PECAP), the effect of polarity changes on the stimulation of the AGF curve (also referred to herein as "polarity effect"), and the effect of measurement latency of the neural response, as well as other techniques known to those skilled in the art. Because the EVT and / or TIM techniques described above characterize the electrical properties of the electrodes and the tissue surrounding the electrode assembly, a neural health map can be determined by creating channels using EVT measurements and / or TIMs determined from EVT measurements. These methods can determine neural health independent of electrode distance and may not obtain knowledge of electrode placement.

[0076] In operation 710, stimulation characteristics for the plurality of neurons are determined based on the neural health map. The determination of the stimulation characteristics may include determining stimulation characteristics for each of the plurality of regions associated with the plurality of neurons. The characteristics determined in operation 710 may include determining which regions associated with the plurality of neurons should be stimulated, the type of stimulation (e.g., monopolar, bipolar, tripolar, etc.), the number or type of stimulation channels (e.g., actual stimulation channels versus virtual stimulation channels), the degree of focus of multipolar stimulation, the excitation spread of the stimulation, the stimulation level, and other characteristics understood by those skilled in the art. Operation 710 may also include additional information, such as a TIM, when determining the stimulation characteristics. Examples utilizing a TIM are described below with reference to Figure 8 describe.

[0077] Finally, in operation 715 , a plurality of neurons are stimulated through the electrodes based on the stimulation characteristics determined in operation 710 .

[0078] Now refer to Figure 8 Flowchart 800 describes a specific example of determining stimulation parameters using a neural health map. The specific example of flowchart 800 uses a TIM in conjunction with a neural health map to set stimulation parameters for electrodes used in stimulation of neurons. Flowchart 800 begins at operation 805 and proceeds to operation 810, where a TIM for an electrode to be used in stimulation is determined.

[0079] As discussed above, TIM refers to a matrix of electrical measurements that can be used to infer the state of electrode array insertion into the cochlea (e.g., positioning, integrity of the electrode array, and abnormal events). In other words, TIM characterizes the electrical properties of the electrode and the tissue surrounding the electrode assembly. For example, TIM can be used to define stimulation channels, such as controlling Figure 2-4 By using TIM, the width of the stimulus 215a-e, 315a-e and 415a-e can be aimed in a wide or narrow manner, respectively, depending on how much the channel should be focused. Figure 2-4 Other uses of TIM may include determining that an electrode is experiencing "tip folding" (ie, when the electrode array folds over itself) and inferring electrode positioning using EVT techniques.

[0080] Once the TIM is determined in operation 810, the flowchart 800 proceeds to operation 815, where a neural health map is determined. Operation 815 may be referred to above. Figure 2-7 Specifically, the position of the electrode relative to the neuron can be determined based on imaging or another physical measurement value. The position of the electrode can also be determined based on the TIM determined in operation 810.

[0081] Once the locations of the electrodes are determined, the neural response thresholds for each electrode may be determined. The neural response thresholds for each electrode may then be correlated with their known distances to determine a neural health map for the neuron to be stimulated. According to other exemplary embodiments, the neural health map of operation 815 may be determined by other techniques known to those skilled in the art. For example, the neural health map may be determined using ECAP AGF slope, the effect of varying IPG on the AGF curve, and SOE measurements using panoramic PECAP. These methods may determine neural health independent of electrode distance and may not require knowledge of electrode placement.

[0082] As described above, EVT techniques and / or TIMs may also be used when determining the neural health map. Moreover, depending on the manner in which the neural health map is determined, operation 815 may precede operation 810 without departing from the techniques disclosed herein. For example, if operation 815 is performed by Figure 5 If the process illustrated in flowchart 500 is embodied, the neural health map may be determined before or after determining the TIM without departing from the techniques disclosed herein.

[0083] Once the TIM and the neural health map are determined, stimulation parameters are set for the stimulation electrodes in operation 820 and flowchart 800 ends in operation 825 .

[0084] An example of operation 820 may include setting stimulation parameters for channels with good neural survival. Channels in a region with good estimated neural survival indicated by good neural health status in a neural health map may use a greater degree of focus. For the TIM, parameters for this greater degree of focus may be determined. Thus, the greater degree of focus is based on both the neural health map (which identifies the region receiving the greater degree of focus) and the TIM (based on which specific stimulation parameters that will produce the greater degree of focus are determined). According to other examples, if it is assumed that a channel has good neural survival but has a larger electrode-modiolar distance, the amplitude of the stimulated current will be increased on the focused channel based on an increase in the neural response threshold. The channel may be defocused only when required due to compliance. In contrast, channels with poor neural survival indicated by poor neural health status in a neural health map may benefit from being defocused (i.e., providing more monopolar stimulation) to ensure that a sufficient number of neural fibers are replenished. Thus, the neural health map identifies the region receiving defocused stimulation, and the TIM determines the specific stimulation parameters that will produce defocused stimulation.

[0085] According to other examples of operation 820, the number and spacing of stimulation sites from within the electrode array may also be set based on the electrode-modiolar distance and DI, under the assumption that a larger distance and less focus should produce a wider excitation spread. The assumed excitation spread may be set on a per-channel basis or using an average across channels for a simplified solution. For example, Fig. 9 , a graph 910 is shown showing a neural excitation pattern 912 based on a received audio signal 914. Specifically, graph 910 shows areas of the cochlea corresponding to specific frequencies on the x-axis and energy levels at those frequencies on the y-axis. Excitation graph 912 shows how energy would be distributed across areas of the cochlea if the stimulation signal were made proportional to the energy in audio signal 914. As shown, excitation graph 912 does not match audio signal graph 914 due to the concentration of stimulation sites resulting in excitation across overlapping areas. Excitation graph 912 has a loss in fidelity relative to audio signal 914, which can result in a corresponding loss in fidelity in the signal perceived by a cochlear implant recipient.

[0086] Graph 920 similarly illustrates a neural excitation pattern 922 based on a received audio signal 924. Unlike graph 910, excitation graph 922 takes into account a hypothetical excitation spread by widening the spacing of stimulation sites, such that the fidelity of excitation graph 922 is improved compared to excitation graph 912, which can be accompanied by a corresponding increase in fidelity in the signal perceived by a cochlear implant recipient. Techniques for selecting stimulation energies and regions that produce excitation graph 922 distribute energy among regions of the cochlea. However, if energy is distributed to regions of poor neural health, the benefits of these techniques may not be realized. Therefore, neural health maps can be used to better determine stimulation regions and energies to provide improved fidelity for cochlear implant recipients.

[0087] The neural health map can also be used for purposes other than setting stimulation parameters. For example, the sound processing module of a cochlear implant (e.g., Figure 1D The external sound processing module 124 or the implantable sound processing module 158 may include a Fast Fourier Transform (FFT) filter bank. These transforms have a limited resolution. Fig.10 and 11 Explained in more detail, the neural health map can be used in conjunction with warped delay lines to tailor the resolution of the FFT to the specific frequencies of each recipient.

[0088] Fig.10 The signal processor (eg, Figure 1DThe processing chain 1000 in the external sound processing module 124 or the implantable sound processing module 158 of the embodiment of the present invention receives the input audio signal. The processing chain 1000 includes a buffer block 1005, a warp delay line (WDL) block 1010, a fast Fourier transform (FFT) block 1015, and a channel in-line combination (CIC) block 1020. The WDL block 1010 includes N W -1 cascade of first-order all-pass filter sections, such as through Fig.11 The all-pass filter section 1105a-w is shown in FIG. The all-pass section 1105a-w has a transfer function A(z) of the following form:

[0089]

[0090] Where λ is a warping coefficient with a value between -1<λ<1 and z is a complex variable. The parameter λ is responsible for the frequency warping. In particular, by appropriately selecting the value of λ, the resolution of certain frequencies of the input audio signal can be improved. When a single global λ is used for the entire WDL block 1010, a change in λ will increase the resolution of higher frequencies but will be detrimental to the resolution of lower frequencies, or vice versa, depending on the sign of λ. If a corresponding local λ is used for each of the all-pass filter sections 1105a-w, the frequency resolution can be customized for a specific frequency region / band.

[0091] Similar to the above reference Figure 2-9 As discussed, the use of a neural health map can aid in selecting λ appropriately for a particular cochlear implant recipient. For example, a recipient with good neural health at high frequencies can have the global λ value set to increase resolution at higher frequencies, while decreasing resolution at lower frequencies as neural health decreases. On the other hand, a recipient with good neural health at low frequencies can have the global λ value set to increase resolution at lower frequencies while decreasing resolution at high frequencies. If a corresponding local λ is used for each of the all-pass filter sections 1105a-w, the local λ can be set so that the recipient receives increased resolution for the specific frequencies at which the recipient has good neural health.

[0092] Reference now Fig.12 , wherein a flowchart 1200 is depicted, which shows a generalized process for implementing the sound processing techniques of the present disclosure.

[0093] Flowchart 1200 begins at operation 1205, where a neural health map of a plurality of neurons stimulated by a plurality of electrodes (e.g., all or only a subset of the electrodes implanted in a recipient) is determined. According to a specific exemplary embodiment, the determination of operation 1205 can be based on correlating the stimulation necessary to induce a response in the electrode with the distance between the electrode and the neuron. According to other exemplary embodiments, the neural health map of operation 1205 can be determined by other techniques known to those skilled in the art. For example, the neural health map can be determined by techniques such as ECAP AGF slope, the effect of IPG on the AGF curve, and SOE measurement using panoramic PECAP. These methods can determine neural health independent of electrode distance and may not require knowledge of electrode placement.

[0094] In operation 1210, a sound processing characteristic of a signal processor associated with the electrode is determined. The determination of the sound processing characteristic is based on the neural health map. For example, operation 1210 can be embodied as setting a warping coefficient λ of a warping filter bank of the signal processor. The warping coefficient λ of the warping filter bank can be a global warping coefficient of the entirety of the warping filter bank or a local warping coefficient of an all-pass filter portion of the warping filter bank.

[0095] Finally, in operation 1215, the audio signal is processed based on the sound processing characteristics to generate stimulation signals for the plurality of electrodes. For example, operation 1215 may be embodied using Fig.10 The buffer block 1005, WDL block 1010, FFT block 1015 and CIC block 1020 process the signal.

[0096] As previously mentioned, the technology disclosed herein can be applied to any of a variety of situations and used with a variety of different devices. Figure 13-15 An exemplary device that may benefit from the techniques disclosed herein is described in more detail in Figure 2-12 Neural Health Graph Technical Configuration Reference Figure 13-15 The technology disclosed herein can be applied to other medical devices, such as neurostimulators, pacemakers, defibrillators, sleep apnea management stimulators, epilepsy treatment stimulators, tinnitus management stimulators, and vestibular stimulation devices, as well as other medical devices that deliver stimulation to tissues. In addition, the technology described herein can also be applied to consumer devices. These various systems and devices can benefit from the technology described herein.

[0097] Fig.131 is a functional block diagram of an implantable stimulator system 1300 that can benefit from the technology described herein. The implantable stimulator system 1300 includes a wearable device 1301 that acts as an external processor device and an implantable device 1303 that acts as an implanted stimulator device. In an example, the implantable device 1303 is an implantable stimulator device that is configured to be implanted beneath the tissue (e.g., skin) of a recipient. In an example, the implantable device 1303 includes a biocompatible implantable housing 1302. Here, the wearable device 1301 is configured to be percutaneously connected to the implantable device 1303 via a wireless connection to provide additional functionality to the implantable device 30.

[0098] In the example shown, the wearable device 1301 includes one or more sensors 1312, a processor 1314, a transceiver 1318, and a power supply 1348. The one or more sensors 1312 may be one or more units configured to generate data based on sensed activity. In the example where the stimulation system 1300 is a hearing prosthesis system, the one or more sensors 1312 include a sound input sensor, such as a microphone, an electrical input for an FM hearing system, other components for receiving sound input, or a combination thereof. In the case where the stimulation system 1300 is a visual prosthesis system, the one or more sensors 1312 may include one or more cameras or other visual sensors. In the case where the stimulation system 1300 is a cardiac stimulator, the one or more sensors 1312 may include a cardiac monitor. The processor 1314 may be a component (e.g., a central processing unit) configured to control the stimulation provided by the implantable device 30. The stimulation may be controlled based on data from the sensor 1312, a stimulation schedule, or other data. In the case where the stimulation system 1300 is a hearing prosthesis, the processor 1314 can be configured to convert the sound signal received from the sensor(s) 1312 (e.g., acting as a sound input unit) into a signal 1351. The transceiver 1318 is configured to send the signal 1351 in the form of a power signal, a data signal, a combination thereof (e.g., by interleaving the signal), or other signals. The transceiver 1318 can also be configured to receive power or data. The stimulation signal can be generated by the processor 1314 and sent to the implantable device 1303 using the transceiver 1318 for providing stimulation.

[0099] In the illustrated example, implantable device 1303 includes transceiver 1318, power source 1348, and medical device 1311 including electronics module 1310 and stimulator assembly 1330. Implantable device 1303 also includes a hermetically sealed biocompatible implantable housing 1302 that encloses one or more of the components.

[0100] The electronic module 1310 may include one or more other components to provide a medical device function. In many examples, the electronic module 1310 includes one or more components for receiving a signal and converting the signal into a stimulation signal 1315. The electronic module 1310 may also include a stimulator unit. The electronic module 1310 may generate a stimulation signal 1315 or control the delivery of the stimulation signal to the stimulator assembly 1330. In an example, the electronic module 1310 includes one or more processors (e.g., a central processing unit or a microcontroller) connected to a memory component (e.g., a flash memory), the memory component storing instructions that, when executed, cause an operation to be performed. In an example, the electronic module 1310 generates and monitors parameters (e.g., output voltage, output current, or line impedance) associated with generating and delivering stimulation. In an example, the electronic module 1310 generates a telemetry signal (e.g., a data signal) including telemetry data. The electronic module 1310 may send a telemetry signal to the wearable device 1301 or store the telemetry signal in a memory for later use or retrieval.

[0101] Stimulator assembly 1330 can be a component configured to provide stimulation to target tissue. In the example shown, stimulator assembly 1330 is an electrode assembly, which includes an electrode contact array arranged on a lead. The lead can be arranged near the tissue to be stimulated. In the case where system 1300 is a cochlear implant system, stimulator assembly 1330 can be inserted into the cochlea of ​​the recipient. Stimulator assembly 1330 can be configured to deliver a stimulation signal 1315 (e.g., an electrical stimulation signal) generated by electronic module 1310 to the cochlea so that the recipient experiences auditory perception. In other examples, stimulator assembly 1330 is a vibration actuator, which is arranged inside or outside the housing of implantable device 1303 and is configured to generate vibration. The vibration actuator receives stimulation signal 1315 and generates a mechanical output force in the form of vibration based on the stimulation signal. The actuator can deliver vibration to the recipient's skull in a manner that generates movement or vibration of the recipient's skull, thereby generating auditory perception by activating the hair cells in the recipient's cochlea via cochlear fluid movement.

[0102] The transceiver 1318 may be a component configured to transcutaneously receive and / or transmit a signal 1351 (e.g., a power signal and / or a data signal). The transceiver 1318 may be a collection of one or more components that form part of a transcutaneous energy or data transmission system to transmit a signal 1351 between the wearable device 1301 and the implantable device 30. Various types of signal transmission, such as electromagnetic, capacitive, and inductive transmission, may be used to effectively receive or transmit the signal 1351. The transceiver 1318 may include or be electrically connected to the coil 20.

[0103] As shown, the wearable device 1301 includes a coil 1308 for transcutaneously transmitting signals with a coil 1320. As described above, transcutaneously transmitting signals between the coil 1308 and the coil 1320 may include transmitting power and / or data from the coil 1308 to the coil 1320 and / or transmitting data from the coil 1320 to the coil 1308. The power supply 1348 may be one or more components configured to provide operating power to other components. The power supply 1348 may be or include one or more rechargeable batteries. The power of the battery can be received from the power supply and stored in the battery. The power can then be distributed to other components for operation as needed.

[0104] As should be understood, although combined Fig.13 Although specific components are described, the technology disclosed herein can be applied to any of a variety of situations. The above discussion is not intended to indicate that the disclosed technology is only suitable for use in similar Fig.13 In general, the methods and systems herein may be practiced using additional configurations and / or some aspects described may be excluded without departing from the methods and systems disclosed herein.

[0105] Fig.14 An exemplary vestibular stimulator system 1402 is shown, which can be used to implement the embodiments presented herein. As shown, the vestibular stimulator system 1402 includes an implantable component (vestibular stimulator) 1412 and an external device / component 1404 (e.g., an external processing device, a battery charger, a remote control, etc.). The external device 1404 includes a transceiver unit 1460. Thus, the external device 1404 is configured to transmit data (and possibly power) to the vestibular stimulator 1412.

[0106] The vestibular stimulator 1412 includes an implant body (main module) 1434, a lead region 1436, and a stimulation assembly 1416, all configured to be implanted beneath the skin / tissue (tissue) 1415 of a recipient. The implant body 1434 generally includes an airtight sealed housing 1438 in which an RF interface circuit system, one or more rechargeable batteries, one or more processors, and a stimulator unit are disposed. The implant body 134 also includes an internal / implantable coil 1414, which is generally external to the housing 1438 but connected to a transceiver via an airtight feedthrough (not shown).

[0107] Stimulation assembly 1416 includes a plurality of electrodes 1444(1)-(3) disposed in a carrier member (e.g., a flexible silicone body). In this particular example, stimulation assembly 1416 includes three (3) stimulation electrodes, referred to as stimulation electrodes 1444(1), 1444(2), and 1444(3). Stimulation electrodes 1444(1), 1444(2), and 1444(3) serve as an electrical interface for delivering electrical stimulation signals to the vestibular system of a recipient.

[0108] The stimulation assembly 1416 is configured so that a surgeon can implant the stimulation assembly near the recipient's otolith organ via, for example, the recipient's oval window. It should be appreciated that this particular embodiment with three stimulation electrodes is merely illustrative, and that the techniques presented herein can be used with stimulation assemblies with different numbers of stimulation electrodes, stimulation assemblies with different lengths, and the like.

[0109] In operation, the vestibular stimulator 1412, the external device 1404, and / or another external device can be configured to implement the techniques presented herein. That is, the vestibular stimulator 1412, possibly in combination with the external device 1404 and / or another external device, can include an induced bio-response analysis system as described elsewhere herein.

[0110] Fig.15 A retinal prosthesis system 1501 is shown, which includes an external device 1510 (which may correspond to the wearable device 1301) configured to communicate with the retinal prosthesis 1500 via a signal 1551. The retinal prosthesis 1500 includes an implanted processing module 1525 (e.g., which may correspond to the implantable device 1303), and a retinal prosthesis sensor-stimulator 1590 positioned proximate to the recipient's retina. The external device 1510 and the processing module 1525 may communicate via coils 1508, 1520.

[0111] In an example, sensory input (e.g., photons entering the eye) is absorbed by a microelectronic array of a sensor-stimulator 1590 that is hybridized with a glass piece 1592 that includes, for example, an embedded microwire array. The glass may have a curved surface that conforms to the inner radius of the retina. The sensor-stimulator 1590 may include a microelectronic imaging device that may be made of thin silicon containing an integrated circuit system that converts incident photons into electronic charges.

[0112] The processing module 1525 includes an image processor 1523 that communicates with the sensor-stimulator 1590 signals via, for example, leads 1588 extending through a surgical incision 1589 formed in the eye wall. In other examples, the processing module 1525 communicates with the sensor-stimulator 1590 wirelessly. The image processor 1523 processes the inputs into the sensor-stimulator 1590 and provides control signals back to the sensor-stimulator 1590 so that the device can provide outputs to the optic nerve. That is, in alternative examples, the processing is performed by a component adjacent to the sensor-stimulator 1590 or integrated therewith. The charge generated by the conversion of the incident photons is converted into a proportional amount of electronic current, which is input to the nearby retinal cell layer. The cells are excited, and signals are sent to the optic nerve, thereby inducing visual perception.

[0113] The processing module 1525 may be implanted in the recipient and function by communicating with an external device 1510, such as a behind-the-ear unit, a pair of glasses, etc. The external device 1510 may include an external light / image capture device (e.g., located in / on a behind-the-ear unit or a pair of glasses, etc.), while as noted above, in some examples, the light / image is captured by a sensor-stimulator 1590, which is implanted in the recipient.

[0114] Fig.16 16 is a functional block diagram of a computing device 1610 configured to implement aspects of the presented techniques (e.g., to implement aspects of one or more methods described herein). The computing device 1610 is, for example, a personal computer, a server computer, a handheld device, a laptop device, a multiprocessor system, a microprocessor-based system, a programmable consumer electronic product (e.g., a smartphone), a network PC, a minicomputer, a mainframe computer, a tablet computer, a remote control unit, a distributed computing environment including any of the above systems or devices, etc. The computing device 1610 can be a single virtual or physical device operating in a networked environment through a communication link to one or more remote devices, such as an implantable medical device or an implantable medical device system.

[0115] In its most basic configuration, computing device 1610 includes at least one processing unit 1683 and memory 1684. Processing unit 1683 includes one or more hardware or software processors (e.g., central processing units) that can obtain and execute instructions. Processing unit 1683 can communicate with other components of computing system 1610 and control the execution of the other components.

[0116] Memory 1684 is one or more software or hardware-based computer-readable storage media that can be operated to store information that can be accessed by processing unit 1683. Among other things, memory 1684 can store instructions and other data that can be executed by processing unit 1683 to implement applications or enable operations described herein to be performed. Memory 1684 can be volatile memory (e.g., RAM), non-volatile memory (e.g., ROM), or a combination thereof. Memory 884 can include temporary memory or non-temporary memory. Memory 1684 can also include one or more removable or non-removable storage devices. In an example, memory 1684 can include RAM, ROM, EEPROM (electrically erasable programmable read-only memory), flash memory, optical disk storage, magnetic storage, solid-state storage, or any other storage medium that can be used to store information for later access. In an example, memory 1684 contains a modulated data signal (e.g., a signal whose one or more characteristics are set or changed in a manner to encode information in the signal), such as a carrier or other transmission mechanism, and includes any information transfer medium. By way of example and not limitation, memory 1684 may include wired media (e.g., a wired network or direct wired connection), as well as wireless media (e.g., acoustic, RF, infrared, and other wireless media), or a combination thereof. In some embodiments, memory 1684 includes neural graph logic 1685, which, when executed, enables processing unit 1683 to perform various aspects of the presented techniques.

[0117] In the example shown, system 1610 also includes a network adapter 1686, one or more input devices 1687, and one or more output devices 1688. System 1610 may include other components such as a system bus, component interfaces, a graphics system, a power source (e.g., a battery), and other components.

[0118] The network adapter 1686 is a component of the computing system 1610 that provides network access (e.g., access to at least one network 1689). The network adapter 1686 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 (radio frequency), etc. The network adapter 1686 may include one or more antennas and associated components configured to communicate wirelessly according to one or more wireless communication technologies and protocols.

[0119] One or more input devices 1687 are devices through which the computing system 1610 receives input from a user. One or more input devices 1687 may include physically actuatable user interface elements (e.g., buttons, switches, or dials), touch screens, keyboards, mice, pens, and voice input devices, among other input devices.

[0120] One or more output devices 1688 are devices through which computing system 1610 can provide output to a user. Output devices 1688 may include a display 1690 and one or more speakers 1691, among other output devices.

[0121] In one embodiment, the network adapter 1686 (or another type of input / interface) can be configured to send instructions to an implantable device (e.g., a cochlear implant) or receive data from the implantable device, or receive data from a component that communicates with the implantable device (e.g., directly with the cochlear implant or with a sound processor inductively coupled to the cochlear implant). The processing unit 1683 can execute the neural graph logic 1685 to perform one or more of the calculations, correlations, and other operations described herein to, for example, generate a neural graph. The output device 1688 can be used to provide the results to a user.

[0122] It should be appreciated that the arrangement of the computing system 1610 shown in FIG. 1E is merely illustrative, and aspects of the technology presented herein can be implemented on many different types of systems / devices. For example, the computing system 1610 can be a laptop, a tablet computer, a mobile phone, a surgical system, etc.

[0123] It should be understood that although specific uses of the present technology have been illustrated and discussed above, the disclosed technology can be used with various devices according to many examples of the present technology. The above discussion is not intended to indicate that the disclosed technology is only suitable for implementation in systems similar to those shown in the accompanying drawings. 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.

[0124] The present disclosure describes some aspects of the present invention technology with reference to the accompanying drawings, in which only some possible aspects are shown. However, other aspects may be embodied in many different forms and should not be construed as being limited to the aspects set forth herein. Instead, these aspects are provided to make the present disclosure detailed and complete and to fully convey the scope of possible aspects to those skilled in the art.

[0125] It should be understood that the various aspects (e.g., parts, components, etc.) described herein with respect to the figures are not intended to limit the systems and processes to the specific aspects described. Therefore, 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.

[0126] According to certain aspects, a system and a non-transitory computer-readable storage medium are provided. The system is configured with hardware, and the hardware is configured to perform operations similar to the method of the present disclosure. One or more non-transitory computer-readable storage media include instructions, and the instructions, when executed by one or more processors, cause the one or more processors to perform operations similar to the method of the present disclosure.

[0127] Similarly, where steps of a process are disclosed, these steps are described for the purpose of illustrating the present methods and systems, and are not intended to limit the present disclosure to a particular sequence of steps. For example, the steps may be performed in a different order, two or more steps may be performed simultaneously, additional steps may be performed, and disclosed steps may be eliminated without departing from the present disclosure. Furthermore, the disclosed processes may be repeated.

[0128] Although specific aspects are described herein, the scope of the present technology is not limited to these specific aspects. Those skilled in the art will recognize other aspects or improvements within the scope of the present technology. Therefore, specific structures, actions or media are disclosed only as illustrative aspects. The scope of the present technology is limited by the following claims and any equivalents therein.

[0129] It should also be understood that the embodiments presented herein are not mutually exclusive and that various embodiments can be combined with another embodiment in any of a variety of different ways.

Claims

1. A method comprising: for each electrode in the plurality of electrodes, determining a distance between each electrode in the plurality of electrodes and one or more neurons; determining a stimulation threshold for each of the plurality of electrodes to induce a response in the one or more neurons; correlating the stimulation threshold for each of the plurality of electrodes to the distance between each of the plurality of electrodes and the one or more neurons; as well as Based on correlating the stimulation threshold of each of the plurality of electrodes with the distance between each of the plurality of electrodes and the one or more neurons, a neural health map of the one or more neurons is generated.

2. The method of claim 1 , wherein determining the stimulation threshold at which each of the plurality of electrodes induces a response in the one or more neurons comprises: An electrically evoked compound action potential (ECAP) threshold is determined for each electrode of the plurality of electrodes.

3. The method according to claim 1 or 2, wherein generating a neural health map of the plurality of electrodes based on the mutual correlation comprises: comparing a distance between a first electrode of the plurality of electrodes and a first region associated with the one or more neurons to the stimulation threshold of the first electrode of the plurality of electrodes; as well as A health level of the first region is determined based on the comparison of the distance between the first electrode of the plurality of electrodes and the first region associated with the one or more neurons and the stimulation threshold of the first electrode.

4. The method of any one of claims 1 or 2, wherein the plurality of electrodes comprises a plurality of electrodes of a cochlear implant.

5. The method of claim 4, wherein the one or more neurons comprise neurons disposed within a cochlea of ​​a recipient of the cochlear implant.

6. The method of any one of claims 1 or 2, wherein the plurality of electrodes comprises a plurality of electrodes of an implantable stimulator system.

7. The method of any one of claims 1 or 2, wherein the plurality of electrodes comprises a plurality of electrodes of a vestibular stimulator system.

8. The method of any one of claims 1 or 2, wherein the plurality of electrodes comprises a plurality of electrodes of a retinal prosthesis system.

9. The method of any one of claims 1 or 2, wherein determining the distance between each of the plurality of electrodes and one or more neurons comprises imaging each electrode using computed tomography imaging.

10. The method of any one of claims 1 or 2, wherein determining the distance between each electrode of the plurality of electrodes and one or more neurons comprises imaging each electrode using magnetic resonance imaging.

11. The method of any one of claims 1 or 2, wherein the plurality of electrodes is a subset of electrodes implanted in a recipient.

12. A method comprising: determining a neural health map of a plurality of neurons stimulated by a plurality of electrodes; determining stimulation characteristics for the plurality of neurons based on the neural health map; as well as The plurality of neurons are stimulated via the plurality of electrodes based on the stimulation characteristics.

13. The method of claim 12, wherein determining the neural health map comprises determining neural health of a plurality of regions associated with the plurality of neurons. The method of claim 13 , wherein determining the stimulation characteristic comprises determining a stimulation characteristic for each of the plurality of regions.

15. The method of claim 12, wherein determining the neural health map of the plurality of neurons comprises: for each electrode in the plurality of electrodes, determining a distance between each electrode in the plurality of electrodes and one or more neurons in the plurality of neurons; determining a stimulation threshold for each of the plurality of electrodes to induce a response in the one or more neurons; correlating the stimulation threshold for each of the plurality of electrodes to the distance between each of the plurality of electrodes and the one or more neurons; as well as The neural health map of the plurality of neurons is generated by correlating the stimulation threshold of each of the plurality of electrodes with the distance between each of the plurality of electrodes and the one or more neurons.

16. The method of any one of claims 12-15, wherein the plurality of electrodes comprises a plurality of electrodes of a cochlear implant.

17. The method of any one of claims 12-15, further comprising determining a transimpedance matrix of the plurality of electrodes.

18. The method of claim 17, wherein determining the stimulation characteristic comprises determining the stimulation characteristic based on the transimpedance matrix.

19. The method of any one of claims 12-15, wherein determining the stimulation characteristic comprises determining a degree of focus of a focused multipolar stimulation of the plurality of neurons.

20. A method comprising: determining a neural health map of a plurality of neurons stimulated by a plurality of electrodes; determining a sound processing characteristic based on the neural health map; as well as The audio signal is processed based on the sound processing characteristic to generate stimulation signals for the plurality of electrodes.

21. The method of claim 20, wherein determining the sound processing characteristics comprises determining settings for a warp filter bank included into a cochlear implant sound processor.

22. The method of claim 21, wherein determining the sound processing characteristics comprises setting a warping coefficient of the warping filter bank based on the neural health map.

23. The method of claim 22, wherein the warping coefficient comprises a global warping coefficient for the entirety of the warping filter bank.

24. The method of claim 22, wherein the warping coefficient comprises a local warping coefficient of an all-pass filter portion of the warped filter bank.

25. The method of claim 20, wherein determining the neural health map of the plurality of neurons comprises: for each electrode in the plurality of electrodes, determining a distance between each electrode in the plurality of electrodes and one or more neurons in the plurality of neurons; determining a stimulation threshold for each of the plurality of electrodes to induce a response in the one or more neurons; correlating the stimulation threshold for each of the plurality of electrodes to the distance between each of the plurality of electrodes and the one or more neurons; as well as The neural health map of the plurality of neurons is generated by correlating the stimulation threshold of each of the plurality of electrodes with the distance between each of the plurality of electrodes and the one or more neurons.

26. One or more non-transitory computer-readable storage media comprising instructions that, when executed by a processor, cause the processor to: For each electrode in the plurality of electrodes, obtaining a distance between each electrode in the plurality of electrodes and one or more neurons; obtaining a stimulation threshold at which each electrode of the plurality of electrodes induces a response in the one or more neurons; correlating the stimulation threshold for each of the plurality of electrodes to the distance between each of the plurality of electrodes and the one or more neurons; as well as The hearing device is configured based on the correlation of the stimulation threshold of each electrode of the plurality of electrodes and the distance between each electrode of the plurality of electrodes and the one or more neurons.

27. The one or more non-transitory computer-readable storage media of claim 26, wherein the instructions operable to obtain the stimulation threshold at which each of the plurality of electrodes induces a response in the one or more neurons comprises instructions operable to: An electrically evoked compound action potential threshold is determined for each electrode of the plurality of electrodes.

28. The one or more non-transitory computer-readable storage media of any one of claims 26 or 27, wherein the instructions operable to correlate the stimulation threshold for each of the plurality of electrodes to the distance between each of the plurality of electrodes and the one or more neurons comprise instructions operable to: comparing a distance between a first electrode of the plurality of electrodes and a first region associated with the one or more neurons to the stimulation threshold of the first electrode of the plurality of electrodes; and A health level of the first region is determined based on the comparison of the distance between the first electrode of the plurality of electrodes and the first region associated with the one or more neurons and the stimulation threshold of the first electrode.

29. The one or more non-transitory computer-readable storage media of any one of claims 26 or 27, wherein the instructions operable to obtain the distance between each electrode of the plurality of electrodes and one or more neurons comprise instructions operable to: The distance between each electrode of the plurality of electrodes and one or more neurons is determined based on imaging data.

30. The one or more non-transitory computer-readable storage media of claim 29, wherein the imaging data comprises computed tomography imaging data.

31. The one or more non-transitory computer-readable storage media of claim 29, wherein the imaging data comprises magnetic resonance imaging data.

32. The one or more non-transitory computer-readable storage media of claim 29, wherein the instructions operable to configure the hearing device based on the correlation between the stimulation threshold of each of the plurality of electrodes and the distance between each of the plurality of electrodes and the one or more neurons comprise instructions operable to: Stimulation characteristics are determined for use by the hearing device when stimulating each neuronal region of the plurality of neuronal regions.

33. The one or more non-transitory computer-readable storage media of claim 32, further comprising instructions operable to: A transimpedance matrix for the plurality of electrodes is determined.

34. The one or more non-transitory computer-readable storage media of claim 32, wherein the instructions operable to determine stimulation characteristics to be used by a hearing device in stimulating each of a plurality of neuronal regions comprise instructions operable to: A degree of focus of the focused multipolar stimulation is determined for use by the hearing device in stimulating each neuronal region of the plurality of neuronal regions.

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