Fully-implanted cochlear implant device based on biomimetic basement membrane sensor

Abstract

The application relates to a full-implant artificial cochlea device based on a biomimetic basement membrane sensor, which comprises an ABM biomimetic array sensing module, a preamplifier, a filter, a gain amplifier, an implant stimulating electrode, a bias voltage feedback adjusting module and an external interface, the ABM biomimetic array sensing module comprises a plurality of narrow-band frequency ABM sensors, each ABM sensor only responds to acoustic excitation in a certain specific narrow-band frequency range, and each ABM sensor has conjugate characteristics; the ABM biomimetic array sensing module, the implant stimulating electrode, the bias voltage feedback adjusting module and the external interface constitute an EcochG feedback tracing module, the EcochG feedback tracing module is used for acquiring a CM signal under the stimulation of the external interface in response to the implant stimulating electrode, and realizes the optimized matching of each ABM sensor and the implant stimulating electrode. Compared with the prior art, the application has the advantages of improving the hearing experience, improving the feasibility and stability and the like.

Description

Technical Field

[0001] This invention relates to the field of surgical medical devices, specifically to a cochlear implant, and more particularly to a fully implantable cochlear implant device based on a biomimetic basilar membrane sensor. Background Technology

[0002] Current cochlear implant technology involves extracting the full-frequency sound signal, performing a Fourier transform (FT) to extract components of the sound signal at different frequencies, and then allocating the stimulation current intensity of the implanted electrodes based on the amplitude spectrum of the frequency components. To achieve real-time hearing transmission in the cochlear implant, the frequency division processing of the signal and the delay in current delivery cannot be too high. High-speed processing with short delays requires high-power processor chips, increasing the power burden on the entire system. Meanwhile, wideband sensors, due to their simple one-piece molding process, cannot finely adjust the frequency response curve, are prone to local signal drift, and cannot be adjusted after implantation. Traditional cochlear implants use integrated microphones, such as external neodymium magnet microphones or other single piezoelectric materials (lead zirconate titanate PZT, polyvinylidene fluoride PVDF, aluminum nitride AlN, etc.), all designed with resonant frequencies far from the sampling range to obtain a relatively flat frequency response curve. Although one-piece molding offers relatively good durability, the frequency response curve still drifts, and its sensitivity and minimum response intensity in the relatively low and high frequency ranges of human hearing remain insufficient. Therefore, in practical use, the effective frequency range is only applicable to a portion of human hearing. Currently, the external microphone response frequency range of most cochlear implants is 100-8000Hz, which covers commonly used speech frequencies (500-4000Hz). However, the actual range of human hearing is 20-20000Hz, and the microphone in the high and low frequency ranges still cannot effectively monitor acoustic signals. As a result, many patients have poor speech recognition in noisy environments and cannot appreciate wide-frequency musical works.

[0003] Since the 1970s, patients with cochlear implants have relied on the magnetic coil of an external cochlear implant to power the internal stimulation electrodes. This has led to several drawbacks associated with the external device. These include: 1. Facial anxiety and shame caused by wearing the external device; 2. The time and financial costs of reconfiguring a lost external device; 3. The inability to wear the external device during rain, swimming, or bathing to avoid water damage; 4. Damage to the magnetic coil connecting the external device to the subcutaneous temporal bone, requiring surgical repair or replacement, causing additional harm to the patient. Therefore, achieving complete implantation of the cochlear implant, eliminating the need for an external implant to reduce the risk of damage, loss, and further harm to the patient, is one of the most pressing technical challenges in cochlear implant technology.

[0004] Due to potential millimeter-level insertion depth errors during surgical implantation, as well as individual anatomical variations in cochlear depth and width, the implanted stimulation electrodes may not reach the preset position during actual implantation. This results in a difference between the frequency of the nerve impulses generated by the electrode rings in the auditory center and the actual sound frequency. To address this critical issue, traditional cochlear implants use EABR (Electrically Evoked Auditory Brainstem Response) and ECAP (Electrically Evoked Auditory Neurological Compound Action Potential) for approximate localization. Then, chip algorithms adjust the output electrode rings, re-pairing them with new electrode rings after frequency resolution to achieve adjustment. The drawback of this method is that both EABR and ECAP require active output current pulses to activate the auditory pathway feedback, leading to inaccurate frequency localization. EABR can only roughly determine the position based on amplitude, and because it is a far-field potential, it is susceptible to interference from various noise potentials. Furthermore, due to significant individual variations in its baseline amplitude, the adjustment results are often inaccurate, frequently resulting in a misalignment between the patient's auditory perception generated by the cochlear implant and the actual sound signal, leading to auditory drift. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a fully implantable cochlear implant based on a biomimetic basilar membrane sensor that can improve the auditory experience, feasibility and stability.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A fully implantable cochlear implant device based on a biomimetic basilar membrane sensor includes an ABM biomimetic array sensing module, a preamplifier, a filter, a gain amplifier, an implantable stimulation electrode, a bias voltage feedback adjustment module, and an external interface. The ABM biomimetic array sensing module, preamplifier, filter, gain amplifier, implantable stimulation electrode, and external interface are connected sequentially. The bias voltage feedback adjustment module is connected to the ABM biomimetic array sensing module, implantable stimulation electrode, and external interface.

[0008] The ABM bionic array sensing module includes multiple narrowband frequency ABM sensors. Each ABM sensor responds only to acoustic excitation within a specific narrowband frequency range, and each ABM sensor has conjugate characteristics.

[0009] The ABM bionic array sensing module, implanted stimulation electrode, bias voltage feedback adjustment module, and external interface constitute the EcochG feedback recording module. This EcochG feedback recording module is used to acquire and receive CM signals from the implanted stimulation electrode in response to stimulation from the external interface, thereby achieving optimized matching between each ABM sensor and the implanted stimulation electrode.

[0010] Furthermore, the ABM biomimetic array sensing module is a helical composite cantilever beam structure, including a helical base shaft, with one end of each ABM sensor being a fixed end located on the helical base shaft, and the other end being a free end.

[0011] Furthermore, the fixed ends of all the ABM sensors point to the center point of the helical base shaft.

[0012] Furthermore, the ABM sensor includes a protective layer, a PDMS encapsulation layer, a P(VDF-TrFE) piezoelectric layer, a graphene layer, and an alloy layer. The P(VDF-TrFE) piezoelectric layer, the graphene layer, and the alloy layer are arranged sequentially to form a sandwich structure with adjustable performance. The PDMS encapsulation layer and the protective layer encapsulate the sandwich structure from the inside out. Electrode layers are also provided on both sides of the P(VDF-TrFE) piezoelectric layer.

[0013] Furthermore, the properties include elastic modulus, Poisson's ratio, and density.

[0014] Furthermore, through reverse calculation, the properties of different materials in the ABM sensor are adjusted so that the basic resonant frequency of the ABM sensor meets a specific narrowband frequency range.

[0015] Furthermore, by designing the length and width of the P(VDF-TrFE) film, the thickness of the graphene layer, the thickness of the alloy layer, and the thickness of the PDMS layer, the properties of different materials in the ABM sensor can be adjusted.

[0016] Furthermore, achieving optimized matching between each of the ABM sensors and the implanted stimulation electrodes specifically includes:

[0017] The location of the implantable stimulation electrode that best matches that specific frequency is determined by finding the electrode corresponding to the maximum CM amplitude using a narrow-band short pure tone at a specific frequency corresponding to the ABM sensor; or...

[0018] By gradually varying the frequency, the optimal matching frequency for a given implant stimulation electrode is found, and the ABM sensor is designed accordingly.

[0019] Furthermore, adjusting the ABM sensor specifically involves:

[0020] The bias voltage feedback adjustment module generates a bias voltage based on the recording results of the EcochG feedback recording module, corrects the resonant frequency of the ABM sensor, and matches the position of the ABM sensor with the implanted stimulation electrode.

[0021] Furthermore, the helical base shaft is a carbon fiber base shaft.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. This invention employs a combination of different technical specifications of composite materials to adjust the overall Poisson's ratio, elastic modulus, and density of the sensor, thereby controlling the resonant frequency of the sensor's cantilever beam. Combined with a filter, this achieves a narrowband acoustic sensor that closely approximates the physiological working mode of the human ear's basilar membrane, resulting in a higher degree of positional matching with the implanted stimulation electrodes and superior auditory experience. The array of ABM acoustic sensors allows for a wider frequency range and a more balanced frequency response. This invention increases the spectral coverage of the acoustic sensor, resulting in a smoother frequency response curve and enhanced auditory experience.

[0024] 2. This invention uses intracochlear electrocochleography (IC ECochG) technology to determine the position of the implanted stimulation electrode and utilizes the cochlear microphonic potential (CM) for positioning calibration of the implanted stimulation electrode. CM is a near-field potential with a higher signal-to-noise ratio, and it can also match the positional relationship between the positioning electrode and the hair cell response frequency based on auditory frequency matching, resulting in higher accuracy in position verification and frequency matching. This invention can reduce chip operating load and system power consumption, increase the feasibility and stability of the fully implantable cochlear implant system, and improve the matching degree between the sensor signal output logic and the current release logic of the stimulation electrode.

[0025] 3. This invention adjusts the resonant frequency by biasing the voltage, and can still make minor corrections to the relatively fixed resonant frequency after production to improve the accuracy of the system. This compensation mechanism makes the system more flexible and personalized, and realizes precision medicine.

[0026] 4. Traditional cochlear implant sensors typically consist of an external unit, an internal unit, and a cochlear implant stimulation electrode. This invention, however, is a fully implantable cochlear implant device. The implant is entirely within the body, with no external components, resulting in minimal surgical scarring and significantly reducing patient anxiety and shame regarding appearance. Because there is no external unit (the external unit of traditional cochlear implants is replaced by an ABM sensor implanted in the middle ear), there is no risk of loss. The ABM sensor and other implanted structures are all located within a closed cavity of the body (the ABM sensor is isolated from the outside by the tympanic membrane in the middle ear), eliminating the risk of external liquids entering the device and causing damage. All implants are located deep within the temporal bone (specifically, the ABM sensor, chip, cochlear implant, etc., are all located deep within the temporal bone), making them impervious to normal bumps and knocks, reducing the risk of device damage and bodily injury from impacts. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention;

[0028] Figure 2This is a schematic diagram of the ABM biomimetic array sensing module of the present invention;

[0029] Figure 3 This is a schematic diagram of a single ABM sensor according to the present invention. Detailed Implementation

[0030] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0031] like Figure 1 As shown, this embodiment provides a fully implantable cochlear implant device based on a bionic basic membrane sensor, including an ABM (artificial basic membrane) bionic array sensing module 1, a preamplifier 2, a filter 3, a gain amplifier 4, an implant stimulation electrode 5, a bias voltage feedback adjustment module 6, and an external interface 7. The ABM bionic array sensing module 1, preamplifier 2, filter 3, gain amplifier 4, implant stimulation electrode 5, and external interface 7 are connected in sequence. The bias voltage feedback adjustment module 6 is connected to the ABM bionic array sensing module 1, implant stimulation electrode 5, and external interface 7 respectively. The ABM bionic array sensing module 1 serves as a sound receiving device, comprising multiple narrowband frequency ABM sensors. Each ABM sensor responds only to acoustic excitation within a specific narrowband frequency range, and each ABM sensor possesses conjugate characteristics. Its main functions include sound signal collection, sound signal processing, and partial distribution of stimulation current. The ABM bionic array sensing module 1, the implanted stimulation electrode 5, and the external interface 7 constitute the EcochG feedback recording module. This EcochG feedback recording module acquires the CM signal received from the implanted stimulation electrode, achieving optimized matching between each ABM sensor and the implanted stimulation electrode. The bias voltage feedback adjustment module 6 generates a bias voltage based on the optimized matching result of the EcochG feedback recording module, correcting the resonant frequency of the ABM sensors to match their position with the implanted stimulation electrode. In the aforementioned fully implantable cochlear implant device, each ABM acoustic sensor, after receiving the gain signal from the preamplifier, undergoes individual filtering. Only the mV-level voltage signal generated by the target frequency excitation is allowed as a valid signal, while voltage signals less than 1mV are filtered as noise signals. The output voltage signal is transmitted to the gain amplifier through a platinum-iridium alloy wire, and then converted into a pulse current released by the implant stimulation electrode.

[0032] Existing electrode fabrication technologies and current diffusion effects mean that the position, number, and density of the electrode rings in cochlear implant stimulation electrodes are almost fixed. Unless there are major technological breakthroughs or changes in the stimulation logic, cochlear implant stimulation electrodes worldwide generally stimulate the spiral ganglion corresponding to the basilar membrane in the 400-20000Hz range, based on the different morphological distribution of the hair cells outside the basilar membrane, to produce hearing at the corresponding frequency. In the ABM bionic array sensing module described in this embodiment, the frequency range of each ABM sensor is designed based on the existing frequency range of cochlear implant stimulation electrode arrays, so that each ABM acoustic sensor only responds to acoustic excitation near a specific frequency.

[0033] In this embodiment, all ABM sensors in the ABM bionic array sensing module have conjugate characteristics, meaning that acoustic excitation activates the sensor response through the same conduction path. To achieve this conjugate characteristic, this embodiment designs the overall ABM bionic array sensing module as a helical composite cantilever beam structure, referencing... Figure 2 As shown, each ABM sensor 12 forms a cantilever sensor, with the free end of the cantilever located inside the tympanic cavity and the fixed end located on a spirally distributed helical base shaft 11 to achieve maximum space utilization. The helical base shaft 11 is made of carbon fiber. The bottom of the base shaft is connected to the stapes footplate and loosely fixed with a small amount of bone cement material to form a new joint structure. The excitation sound travels through the natural air conduction hearing path of the human ear, i.e., collected by the auricle—focused by the external auditory canal—vibrated by the tympanic membrane—amplified step by step by the lever action of the ossicular chain, and finally the excitation sound vibration with a physiological gain of 40-60dB of the original external sound is transmitted to the fixed shaft of the ABM sensor, causing the vibration of all the cantilever sensors on the shaft. In this embodiment, the fixed ends of all narrowband ABM sensors 12 point to the center point of the spiral, and the free vibrating ends point outward, forming a conjugate structure, which enables the multi-sensor array to output signals with better synchronization and signal extraction efficiency.

[0034] In the aforementioned ABM bionic array sensing module, the spiral base shaft is used to connect all narrowband frequency ABM sensor arrays, providing a holistic design. The spiral base shaft has high space utilization efficiency, making it convenient for applications with small size requirements. All fixed ends of the narrowband sensors point to the center point of the spiral, while the free vibrating ends point outwards, forming a conjugate structure that enables the multi-sensor array to output signals with good synchronization and signal extraction efficiency.

[0035] In this embodiment, each acoustic sensor can only generate a response signal to a specific frequency and a narrow band of acoustic excitation in its surrounding spectrum. To achieve this function, the target frequency is set by adjusting the overall resonant frequency of the sensor cantilever.

[0036] In this embodiment, reference Figure 3As shown, the structure of a single ABM sensor 12 consists of a Ti film protective layer 125, a PDMS encapsulation layer 124, a P(VDF-TrFE) piezoelectric layer 121, an Au electrode layer 126, a graphene layer 122, and an alloy layer 123.

[0037] The fabrication process of a single ABM sensor is as follows: The ternary polymer PVDF material is reacted with polyethylene fluoride to form a vinylidene fluoride-trifluoroethylene polymer (P(VDF-TrFE)) material. The PVDF-TrFE material is repeatedly rinsed with an organic solvent and then dissolved in dimethylformamide solvent. A 2 mm x mm x a μm P(VDF-TrFE) thin film is prepared by solution drying. 20 nm gold electrodes are deposited on both sides of the film using magnetron sputtering, and a 0.05 mm diameter platinum wire is bonded to each side of the film using conductive silver paste. A b μm thick graphene film is deposited on a rectangular plane on one side of the P(VDF-TrFE)-Au device using vapor deposition. A c μm thick alloy plate is placed on the graphene layer, forming an alloy-graphene-P(VDF-TrFE) sandwich structure. The purpose of this structure is to harmonize the overall elastic modulus, Poisson's ratio, and density of the sensor by utilizing the different elastic moduli, Poisson's ratio, and densities of the different materials. The outer side of this structure is entirely encapsulated with PDMS with a thickness of d μm to achieve insulation, protect the internal structure from contact with biological tissue fluid, improve durability, and prevent short circuits in piezoelectric components from affecting signal output. A 20nm titanium film is then deposited on the outer layer of PDMS using magnetron sputtering to further enhance overall biocompatibility and PDMS durability.

[0038] Because an object resonates under external excitation at the same resonant frequency, the energy of the vibration and the corresponding piezoelectric material signal output are amplified by several orders of magnitude. Therefore, by setting the resonant frequency of the sensor and using a filter with a high threshold to filter out signals with responses below the resonant frequency, the response at the resonant frequency can be output, thus realizing the function of a narrowband acoustic sensor.

[0039] The aforementioned single sensor was laser-welded to a prefabricated carbon fiber spiral support, forming a cantilever beam structure. Using the calculation formula for the first mode vibration resonant frequency of the cantilever beam, the target frequency was set to the frequency corresponding to the stimulation electrode ring of the implant. AI was used to reverse-engineer the technical specifications and proportions of each material that met the above conditions and actual manufacturing precision (i.e., to solve for the values ​​of x, a, b, c, and d under different resonant frequency designs). The narrowband acoustic sensor unit was then manufactured according to the AI ​​calculation results.

[0040] The fundamental resonant frequency (first mode resonant frequency) of a cantilever beam can be calculated using the following formula:

[0041]

[0042] In the formula, f It is the fundamental resonant frequency of the cantilever beam. E It is the Young's modulus of the material. I It is the area moment of inertia of the cross section. ρ It refers to the density of the material. A It is the cross-sectional area of ​​the beam. L It is the length of the beam.

[0043] Calculate the area moment of inertia of the cross section I For rectangular cross-sections (width) b ,thickness h The formula for calculating the moment of inertia is as follows:

[0044]

[0045] Due to different clinical needs, commercially available implantable stimulation electrodes have different numbers and positional density ratios of electrode rings. The advantage of the above calculation is that different frequencies of implantable stimulation electrodes can be adapted through simple adjustment of technical specifications.

[0046] In this embodiment, the frequency distribution of common CI622 implant stimulation electrodes is used as an example: Electrode 1: approximately 16,000 Hz; Electrode 2: approximately 12,800 Hz; Electrode 3: approximately 10,240 Hz; Electrode 4: approximately 8,192 Hz; Electrode 5: approximately 6,553 Hz; Electrode 6: approximately 5,242 Hz; Electrode 7: approximately 4,193 Hz; Electrode 8: approximately 3,355 Hz; Electrode 9: approximately 2,684 Hz; Electrode 10: approximately 2,147 Hz; Electrode 11: approximately 1,718 Hz; Electrode 12: approximately 1,375 Hz; Electrode 13: approximately 1,100 Hz; Electrode 14: approximately 880 Hz; Electrode 15: approximately 704 Hz; Electrode 16: approximately 563 Hz; Electrode 17: approximately 450 Hz; Electrode 18: approximately 360 Hz. Hz; Electrode 19: approximately 288 Hz; Electrode 20: approximately 230 Hz; Electrode 21: approximately 184 Hz; Electrode 22: approximately 147 Hz.

[0047] The key physical properties of the composite layer material are listed below:

[0048] P(VDF-TrFE): Elastic modulus E PVDF =2.2×10 9 N / m 2 Density: ρ PVDF =1750kg / m 3

[0049] Graphene: Elastic modulus E Graphene =1.0×10 12 N / m 2 density ρ Graphene =2200kg / m 3

[0050] Alloy: Elastic modulus: E Alloy =2×10 11 N / m2, density ρ Alloy =8000kg / m 3

[0051] PDMS: Elastic modulus: E Silicone =0.75×10 6 N / m 2 Density: ρ Silicone =970kg / m 3

[0052] Taking a target frequency of 147Hz as an example, the reverse calculation yields a solution that meets the current processing precision requirements:

[0053] Design a cantilever beam structure with a rectangular shape, a width of 2mm, a length of 4mm, and an overall thickness of T: t PVDF =0.042 mm; t Alloy =0.044 mm; t Graphene =0.054 mm; t Silicone =0.05 mm; Total thickness T=0.24 mm,

[0054] The calculated equivalent elastic modulus and equivalent density of the material as a whole are as follows:

[0055] E composite = = 2.62365×10 11 N / m 2

[0056] ρ composite = = 2672.08kg / m 3

[0057] Substituting into the natural frequency calculation formula, we get:

[0058] I= = 2.88×10 −19 m 4

[0059] A = 0.002 × 0.00024 = 4.8 × 10 −7 m 2

[0060] f 1= 147Hz

[0061] This means that the sensor can output a voltage signal a hundred times greater than that at the same sound pressure level of 147Hz. Actual production verification has shown that the sensor exhibits a piezoelectric effect several times greater than that at its preset resonant frequency.

[0062] Verification of the accuracy of electrode implantation position-frequency coupling:

[0063] In this embodiment, intracochlear electrocochleography (ICECochG) is used to verify accuracy. Precise localization can be achieved as long as the patient has residual hearing (residual functional hair cells at any location). This is because ICECochG can test the cochlear michrophonic (CM) potential, which is generated by hair cells and has the characteristic of faithfully reproducing sound signals; that is, the generated potential signal has the same phase and frequency as the original sound signal, and the amplitude is positively correlated. When a single-frequency narrowband short pure tone (tone burst) is applied, the generated CM is a sinusoidal voltage signal. Furthermore, the CM is a near-field potential; the recording electrode is located close to the hair cells that generate the potential and is also in the perilymph, a good conductor, thus experiencing less interference from other biopotentials. Accuracy verification method: Sound stimulation is applied through the external auditory canal, and electrode rings at different locations within the cochlea are used as cochlear recording electrodes to receive CM signals. Since the amplitude of the near-field potential CM is positively correlated with the electrode-response hair cell distance, the position of the electrode best matched to that frequency can be determined by finding the electrode corresponding to the maximum CM amplitude when a narrow-band short pure tone is applied. Conversely, the optimal matching frequency for a given electrode can be found by stepwise frequency changes. Based on this, the matching degree between the acoustic sensor and the implanted stimulation electrode can be further adjusted to improve the auditory experience.

[0064] In the EcochG feedback recording module described above, the implanted stimulation electrode 5 mainly serves as the recording electrode, reference electrode, and ground electrode during cochlear symptom (CM) testing, and is a necessary structural element for recording CM. The external interface 7 connects to a computer, which in turn connects to a sound player. When the sound player plays a pure-tone acoustic signal, the external interface 7 receives the stimulation sound information. The computer records the CM signal transmitted from the implanted stimulation electrode 5 and plots the waveform, recording the amplitude of the CM wave. This process completes one CM test. Based on the obtained CM test results, the position information of the implanted stimulation electrode (corresponding to the physiological frequency-specific position of the cochlea) and the resonant frequency information of the ABM sensor are matched. In most cases, the preset position and sensor resonant frequency meet the usage requirements. In a few cases of mismatch, the position of the implanted stimulation electrode is adjusted according to the aforementioned adjustment scheme (inserting the entire implanted stimulation electrode deeper or shallower into the cochlea) or the resonant frequency of the ABM sensor is fine-tuned through the bias voltage. This process completes one feedback adjustment.

[0065] The implanted stimulation electrode 5 consists of several electrode rings (or semi-rings) evenly distributed on a thin silicone strip. Each electrode is individually connected to the internal organ via a platinum wire passing through the silicone. Three electrodes are required for CM recording: a recording electrode, a reference electrode, and a ground electrode. In actual use, the position of the recording electrode has a significant impact on the acquired signal. In the setup, any three electrodes from multiple electrodes can be selected as the recording electrode, reference electrode, and ground electrode. For example, using electrode 1 at the tip of the implanted silicone tube as the recording electrode, electrode 2 as the reference electrode, and electrode 3 as the ground electrode, changing the frequency of the external stimulation pure tone will record the corresponding change in the CM signal. When the CM amplitude is at its maximum, it indicates that the outer hair cell of the cochlea producing the maximum response (i.e., the location where the CM potential is generated) is closest to the recording electrode, thus establishing a positional correspondence.

[0066] Feedback adjustment of sensor resonant frequency:

[0067] P(VDF-TrFE) exhibits both piezoelectric effect and the ability to convert voltage into internal stress. By applying a bias voltage at a specific location on P(VDF-TrFE), prestress can be generated within it, altering its frequency response characteristics. Utilizing this principle, the resonant frequency of the acoustic sensor can be corrected based on the CM feedback frequency matching results from the previous steps, aligning it with the position of the cochlear implant stimulation electrode. This matches the resonant frequency of the ABM sensor with the neural response frequency at the corresponding location on the basilar membrane where the implant stimulation electrode is located. This step can be completed during the implantation surgery. The bias voltage can be easily adjusted by activating different numbers of channels in a pre-built microcontroller. Once set, the position of the implant stimulation electrode remains unchanged, and the resonant frequency of the acoustic sensor does not change, thus eliminating the need for additional chip analysis. Even with this feedback adjustment process, the overall power consumption of the system remains significantly lower than that of traditional sensors and cochlear implant systems.

[0068] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A fully implanted cochlear implant device based on a biomimetic basement membrane sensor, characterized in that, The cochlear microphonic potential signal of the cochlea microphone under the stimulation of the external interface receiving the implant stimulation electrode is acquired, and the optimal matching of each artificial basement membrane sensor and the implant stimulation electrode is realized. The cochlear microphonic potential amplitude corresponding to the frequency narrowband tone found by the artificial basement membrane sensor is determined, and the position of the implant stimulation electrode most matched with the frequency is determined. The optimal matching frequency corresponding to the implant stimulation electrode is found through step-by-step frequency change, and the artificial basement membrane sensor is adjusted and designed. The artificial basement membrane sensor is adjusted, and specifically, The bias voltage feedback adjustment module generates a bias voltage based on the recording results of the cochlear microphonic feedback recording module, corrects the resonance frequency of the artificial basement membrane sensor, and matches the position of the artificial basement membrane sensor and the implant stimulation electrode. The artificial basement membrane sensor is a spiral composite cantilever beam structure, including a spiral basement shaft, one end of each artificial basement membrane sensor is a fixed end and is located on the spiral basement shaft, and the other end is a free end. All the fixed ends of the artificial basement membrane sensors point to the center point of the spiral basement shaft. The artificial basement membrane sensor includes a protective layer, a PDMS packaging layer, a P(VDF-TrFE) piezoelectric layer, a graphene layer and an alloy layer, the P(VDF-TrFE) piezoelectric layer, the graphene layer and the alloy layer are sequentially arranged to form a sandwich structure with adjustable performance, the PDMS packaging layer and the protective layer are wrapped from the inside to the outside to encapsulate the sandwich structure, and the P(VDF-TrFE) piezoelectric layer is further provided with an electrode layer on both sides.

2. The bionic basement membrane sensor-based fully-implanted cochlear implant device according to claim 1, wherein, The performance includes elastic modulus, Poisson's ratio and density.

3. The bionic basement membrane sensor-based fully-implanted cochlear implant device according to claim 2, wherein, The performance of different materials in the artificial basement membrane sensor is adjusted through reverse operation, so that the basic resonance frequency of the artificial basement membrane sensor meets the certain narrowband frequency range.

4. The bionic basement membrane sensor-based fully-implanted cochlear device according to claim 1 or 2, characterized in that, The length and width of the P(VDF-TrFE) film, the thickness of the graphene layer, the thickness of the alloy layer and the thickness of the PDMS layer are designed to adjust the performance of different materials in the artificial basement membrane sensor.

5. The bionic basement membrane sensor-based fully-implanted cochlear device according to claim 4, wherein, The spiral basement shaft adopts a carbon fiber basement shaft.

6. The bionic basement membrane sensor-based fully-implanted cochlear device of claim 4, wherein, ​ 7. The bionic basement membrane sensor-based fully-implanted cochlear device according to claim 6, wherein, ​ 8. The bionic basement membrane sensor-based fully-implanted cochlear device of claim 2, wherein, ​

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