A passive cochlear implant device

Abstract

The application belongs to the field of biomedical engineering / sensory function assistance, and discloses a passive cochlear implant device, which comprises a soft substance matrix (1) and at least two piezoelectric units (4), wherein any piezoelectric unit comprises piezoelectric material and electrodes connected to the piezoelectric material on both sides of the piezoelectric material, any two adjacent piezoelectric units are electrically insulated from each other, and each electrode is led out to the outside of the soft substance matrix (1) for stimulating the spiral ganglion under the basilar membrane. Through improvement on the principle of the cochlear implant device and the design of the corresponding components, compared with the existing active electronic cochlear implant, the passive cochlear implant can convert the vibration signals of sound waves into electrical signals with the characteristics of biological cochlea position coding and time coding, can greatly improve the feeling ability of users to music and tone, and can reduce the influence of the traditional electronic cochlear implant on the normal life of people.

Description

Technical Field

[0001] This invention belongs to the field of biomedical engineering / sensory function assistance, and more specifically, relates to a passive cochlear implant device that can be used to restore hearing in hearing-impaired patients. Background Technology

[0002] The main cause of moderate to severe hearing loss is the reduction of auditory hair cells in the cochlea, which restricts sound transmission to the auditory nerve within the cochlea. Currently, the primary clinical approach for treating moderate to severe hearing loss is the implantation of a cochlear implant based on a rigid electronic device. Existing cochlear implants utilize external acoustic sensors to convert sound signals into electrical impulses, which are then further stimulated by electrode sequences implanted within the cochlea to reconstruct auditory function. While existing cochlear implants are effective in restoring functional hearing (such as conversations in quiet environments), they lack precise positional encoding (positional encoding function, i.e., different frequencies perceived at different cochlear positions) and temporal encoding function (temporal encoding function, i.e., the rate of vibration perceived at a single cochlear position, i.e., different frequencies), making it difficult to restore natural hearing in patients with hearing loss. Specifically, cochlear implant users often struggle to appreciate music or distinguish different tones (e.g., difficulty differentiating between different speakers, animals, or vehicles in noisy environments). Meanwhile, cochlear implants also have some issues with ease of use and safety: First, most existing devices are rigid metal components, which do not match the modulus of human tissue well and are prone to infection; second, as active devices with external components, the manufacturing and maintenance costs of existing devices are relatively high, and the waterproofing and battery life issues of the external unit will impose significant limitations on users' lives.

[0003] To address the usability issues inherent in cochlear implants, some patents have attempted to utilize piezoelectric materials to aid in hearing restoration. However, the current patent (CN104602654A) only uses a single piezoelectric material to cover the basilar membrane of the cochlea, failing to achieve the decomposition of sound frequencies at different spatial locations to stimulate the auditory nerves in different parts of the cochlea (the cochlea's positional encoding function). Furthermore, the rigid resonant structure makes it difficult for the overall material to deform significantly to conform to the spiral shape of the scala tympani. Therefore, there is currently no novel cochlear implant product design that can overcome the limitations of electronic cochlear implants. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the existing technology, the purpose of this invention is to provide a passive cochlear implant device. By improving the working principle and corresponding component design of the cochlear implant device, a passive cochlear implant with stronger frequency resolution can be obtained. Compared with the existing active electronic cochlear implant, the cochlear implant of this invention can convert the vibration signal of sound waves into an electrical signal with biological cochlear position encoding and time encoding characteristics, which can significantly improve the user's ability to perceive music and tone, while reducing the impact of traditional electronic cochlear implants on people's normal life.

[0005] To achieve the above objectives, according to the present invention, a passive cochlear implant device is provided, characterized in that it comprises: a soft material substrate (1) and at least two piezoelectric units (4) located on or inside the substrate and distributed along the length of the substrate, wherein each piezoelectric unit (4) comprises a piezoelectric material and electrodes located on both sides of the piezoelectric material and connected to the piezoelectric material, any two adjacent piezoelectric units (4) do not contact each other, and each electrode is led out to the outside of the soft material substrate (1) for electrical stimulation to activate the spiral ganglion below the cochlear basilar membrane.

[0006] As a further preferred embodiment of the present invention, the soft material matrix (1) is a flexible deformable material, preferably a hydrogel, ionogel, organic gel, silicone rubber, polyurethane, thermoplastic elastomer or thermoplastic rubber.

[0007] The piezoelectric material is a solid material with a piezoelectric effect, preferably a composite material of polyvinylidene fluoride and its copolymers, barium titanate, lead zirconate titanate and the above materials;

[0008] The electrode is an alloy electrode, a metal element electrode, an organic conductive material electrode, or an electrode made of any combination of the above materials, preferably gold, silver, copper, or platinum.

[0009] As a further preferred embodiment of the present invention, the piezoelectric material in any one of the piezoelectric units (4) is in the form of a sheet.

[0010] As a further preferred embodiment of the present invention, the soft material matrix (1) is elongated and can be bent into a shape that matches the human cochlea, so as to facilitate implantation into the human cochlea;

[0011] Preferably, the soft material matrix (1) is wedge-shaped and elongated.

[0012] As a further preferred embodiment of the present invention, the length of the soft material matrix (1) is 10-30 mm, and the cross-sectional area of ​​any one cross section is 0.01-4 mm². 2 .

[0013] As a further preferred embodiment of the present invention, the soft material matrix (1) is in a spiral-curved shape that matches the human cochlea.

[0014] As a further preferred embodiment of the present invention, the piezoelectric material is either completely encapsulated inside the soft material matrix (1), or adhered to the surface of the soft material matrix (1), or partially inserted into the soft material matrix (1).

[0015] As a further preferred embodiment of the present invention, along the direction of sound wave transmission, the spacing between the piezoelectric material portions of two adjacent piezoelectric units (4) monotonically increases or monotonically decreases; preferably, the direction of sound wave transmission is denoted as the x-direction, and each piezoelectric unit satisfies:

[0016] x(n)=Aa n +Bn a +Cn+m

[0017] Where x(n) represents the position of the piezoelectric material portion of the nth piezoelectric unit in the x direction; a is any positive number greater than 1; A, B, C, and m are any real numbers.

[0018] Compared with the prior art, the cochlear implant of this invention, employing a passive design of piezoelectric materials, electrodes, and a substrate, can convert sound wave vibration signals into electrical signals with biological cochlear position and time encoding characteristics. When a vibration wave (the manifestation of sound in a solid) enters from one end of the device and propagates within it, the attenuation of the vibration wave at different frequencies and the structural modulation characteristics allow different frequencies of sound waves to stimulate the piezoelectric material at different locations with varying intensities. The piezoelectric material then directly converts the vibration into an electrical signal, stimulating the corresponding spiral ganglion within the cochlea, thereby completing the biological cochlear position and time encoding characteristics.

[0019] In the passive cochlear implant device of this invention, each piezoelectric unit is independent, and the piezoelectric materials in each unit are distributed at a certain distance, with different units not in contact with each other and maintaining mutual electrical insulation (of course, one of the two electrodes of these units can also share a ground wire on the outside by means of an extension line, etc.). When the soft material matrix is ​​laid flat, adjacent piezoelectric materials can be arranged in an approximately parallel manner (of course, they can also be arranged at an angle; the plane where the piezoelectric material is located is as close to perpendicular to the direction of sound wave transmission as possible, and the plane where the electrode plate is located is also as close to perpendicular to the direction of sound wave transmission as possible; regarding the direction of sound wave transmission, when the passive cochlear implant of this invention is implanted into the human cochlea, the cochlear axis can be regarded as the direction of sound wave transmission, at which time the soft material matrix is ​​curved). The entire device can be naturally bent into a spiral shape similar to the internal canal of the cochlea, inserted into the scala tympani of the cochlea, naturally surrounding the cochlear axis, with the exposed electrode part approaching or inserted into different positions of the basilar membrane of the cochlea. During operation, vibration waves (the manifestation of sound in a solid) enter from one end of the device and propagate within it. Based on the device design and the physical characteristics of the vibration, they stimulate piezoelectric materials at different locations. The piezoelectric materials then directly convert the vibration into electrical signals, stimulating the corresponding spiral ganglion in the cochlea on-site, thereby completing the biological cochlear position encoding and time encoding characteristics.

[0020] The soft material matrix of the passive cochlear implant device of this invention can be elongated and bent into a shape that matches the human cochlea for easy implantation. The cross-sectional area of ​​the soft material matrix is ​​0.01–4 mm². 2 The cross-sectional shape can be elliptical, circular, polygonal, or an irregular single-connected shape. The base length is 10-30mm, which can be inserted into the cochlea and encircle the cochlea 2.5 times. The soft material strip can be wedge-shaped after being straightened. The soft material strip can be pre-bent or shaped in a straightened state and then naturally bent before being inserted into the cochlea.

[0021] In use, one end of the device can be adhered to, welded to, or inserted into the ossicular chain to receive sound directly from the ossicles (including the stapes, etc.), while the other end is inserted into the cochlea. Alternatively, the device can be fully inserted into the cochlea, receiving sound from the sound transmitted into the cochlea.

[0022] This invention's device can utilize the user's existing intact outer and middle ear sound transmission amplification systems, easily expanding the number of stimulation channels within the cochlea (corresponding to the number of piezoelectric units in the device) to over 150 (for example, when the length of the soft material substrate is 25 mm, the width of the piezoelectric unit along its length is 60 micrometers, and the spacing between the piezoelectric material portions of two adjacent piezoelectric units remains equal at 100 micrometers, the number of piezoelectric units can easily reach 150 or more). Simultaneously, because this invention utilizes vibration in the device substrate to excite the piezoelectric material to vibrate, the electrical signal generated by the piezoelectric material can completely reproduce the time-domain oscillation information of sound signals (such as rapidly changing signals exceeding 10 kHz exemplified in the later embodiments), allowing patients to not only engage in normal conversation but also better appreciate music and distinguish the sounds of different animals, vehicles, etc., possessing different frequency characteristics. Furthermore, unlike existing active devices, this invention's device eliminates concerns about water ingress, damage, or charging issues with the external unit, exhibits virtually no electromagnetic interference, and can perform magnetic resonance imaging normally without magnets, greatly facilitating the daily life of implant recipients.

[0023] In summary, the passive cochlear implant device of this invention can help patients with hearing loss due to damage or degeneration of cochlear auditory hair cells to restore natural hearing, while maximizing the restoration of their normal life. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the basic structure of the human ear.

[0025] Figure 2 This is a schematic diagram of the cochlear structure and the distribution of the device of the present invention.

[0026] Figure 3 This is a side view of the structure of the first embodiment.

[0027] Figure 4 This is a side view of the structure of the second embodiment.

[0028] Figure 5 This is a side view of the structure of the third embodiment.

[0029] Figure 6 This is a top view of the structure of the fourth embodiment.

[0030] Figure 7 This is a top view of the structure of the fifth embodiment.

[0031] Figure 8 This is a top view of the device in the fifth embodiment, which is bent into a spiral shape.

[0032] Figure 9 This is a top view of the structure of the sixth embodiment.

[0033] Figure 10 This is a top view of the structure of the seventh embodiment.

[0034] Figure 11 This is a simulation diagram of the stress field distribution of the device in the first embodiment under the condition of a vibration wave incident at a frequency of 5.4 kHz.

[0035] Figure 12 This is a simulation diagram of the stress field distribution of the device in the first embodiment under the condition of incident vibration wave with a frequency of 12.6kHz.

[0036] Figure 13 This is a simulation diagram of the stress field distribution of the device in the first embodiment under the condition of incident vibration wave with a frequency of 20kHz.

[0037] Figure 14 This is a simulation diagram of the displacement field distribution of the device in the sixth embodiment under the condition of a vibration wave incident at a frequency of 2.1 kHz.

[0038] Figure 15 This is a simulation diagram of the displacement field distribution of the device in the sixth embodiment under the condition of a vibration wave incident at a frequency of 4.4 kHz.

[0039] Figure 16 This is a simulation diagram of the displacement field distribution of the device in the sixth embodiment under the condition of a vibration wave incident at a frequency of 12kHz.

[0040] Figure 17 This is a simulation diagram of the stress field distribution of the device in the seventh embodiment under the condition of a vibration wave incident at a frequency of 2.1 kHz.

[0041] Figure 18 This is a simulation diagram of the stress field distribution of the device in the seventh embodiment under the condition of a vibration wave incident at a frequency of 2.9 kHz.

[0042] Figure 19 This is a simulation diagram of the stress field distribution of the device in the seventh embodiment under the condition of an incident vibration wave with a frequency of 8.3 kHz.

[0043] The meanings of the labels in the figures are as follows: 1-Soft material matrix, 2-Piezoelectric material sheet, 3-Electrode, 4-Piezoelectric unit (i.e., the unit composed of piezoelectric material 2 and electrode 3); 100-Outer ear, 101-Auricle, 102-Ear canal, 103-Tympanic membrane; 200-Middle ear, 201-Ossicles; 300-Inner ear, 301-Cochlea, 302-Campioid process, 303-Chamfered process, 304-Chamfered process, 305-Basilar membrane, 306-Hair cell, 307-Tectonic membrane, 308-Spinal ganglion, 309-Auditory nerve (i.e., spiral ganglion cell bundle). Additionally, Figures 3 to 10In the structural schematic diagram shown, the structure only represents the geometric topological relationship between different components (i.e. whether they are connected or in contact). The scale of the schematic diagram does not constrain the size and shape of the invention device (for example, the cross-sectional shape of the soft material matrix 1, the piezoelectric material sheet 2, and the electrode 3 shown in the figure is rectangular, but in fact these units can be any shape such as circles, polygons, triangles, etc.). Figures 3 to 7 , Figures 9 to 10 In this example, the number of units 4 is 16. In reality, the number of piezoelectric materials can be any integer greater than or equal to 2, such as an integer greater than or equal to 8. Figures 3 to 5 The middle electrode is located on the two longer sides (left and right sides) of the piezoelectric material, or the electrode can be located on the two shorter sides (top and bottom sides) of the piezoelectric material. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0045] To facilitate understanding, the basic structure of the ear will be described first before introducing the technical solution of the present invention. For example... Figure 1 The diagram shows the basic structure of the human ear. The human ear mainly consists of three parts: the outer ear 100, the middle ear 200, and the inner ear 300. External sound is filtered and collected by the auricle 101, passes through the ear canal 102, and excites the tympanic membrane 103 to vibrate. The tympanic membrane 103 transmits the vibration to the ossicles 201 connected to the tympanic membrane. The ossicles filter and amplify the vibration and conduct it to the cochlea 301. The cochlea is a spiral tube that spirals upwards approximately two and a half times. Figure 2 This is a cross-sectional view of the cochlear structure. Sound propagates in the cochlea 301, causing the basilar membrane 305 to vibrate. The basilar membrane 305 drives the hair cells 306 at the corresponding locations to vibrate. The hair cells 306 convert the vibration signal into an electrical signal in real time and stimulate the connected spiral ganglion 308. The various parts of the auditory nerve 309 (that is, the spiral ganglion cell bundle) transmit the stimulation signal to the brain to form hearing.

[0046] In summary, the passive cochlear implant device of this invention comprises: an external flexible soft material substrate 1 and at least two independent piezoelectric material sheets 2 (different piezoelectric materials not in direct contact), with independent electrodes 3 covering both ends of the piezoelectric materials. The electrodes 3 are extended outside the soft material substrate 1 (that is, a portion of the electrodes 3 is exposed outside the soft material substrate 1). The piezoelectric sheets are distributed at a certain distance, and adjacent piezoelectric materials are approximately parallel to each other.

[0047] Taking polyvinyl alcohol hydrogel as the soft material matrix, polyvinylidene fluoride-trifluoroethylene copolymer as the piezoelectric material, and conductive polyethylene as the electrode material as an example, the following are specific implementation examples:

[0048] First implementation method:

[0049] The passive cochlear implant device corresponding to this embodiment is shown in the side view as follows. Figure 3 As shown, at this point, the piezoelectric material is completely located inside the soft matter matrix.

[0050] During operation, vibration waves (the manifestation of sound in a solid) enter from one end of the device and propagate within it. Utilizing the attenuation of vibration waves at different frequencies within the device and the structural modulation characteristics, sound waves of different frequencies stimulate piezoelectric materials at different locations with varying intensities. The piezoelectric materials then directly convert the vibrations into electrical signals, stimulating the corresponding spiral ganglion within the cochlea on-site. This completes the biological cochlear position and time encoding characteristics and activates previously interrupted auditory pathways.

[0051] Taking a substrate with a length of 24mm and a height of 1.4mm; piezoelectric material with a thickness of 0.16mm and a height of 1mm; electrode material with a thickness of 0.16mm and a height of 1mm (the protruding part of the electrode has a negligible impact on the simulation and is not considered for now); and piezoelectric elements maintaining equal spacing with a center-to-center distance of 1.5mm between adjacent elements as an example, Figures 11 to 13 The strain distribution of different parts of the device was simulated when different sound waves were incident on the device from one end. The white (brighter) areas in the figure represent the locations with larger strains. The piezoelectric material at the corresponding locations is the frequency channel that is mainly activated at the current incident frequency. At this time, the piezoelectric material generates voltage to stimulate the spiral ganglion, completing the position encoding stimulation of the sound wave at the current frequency.

[0052] Second implementation method:

[0053] The passive cochlear implant device corresponding to this embodiment is shown in the side view as follows. Figure 4 As shown, at this time, part or all of the piezoelectric material is located on the surface of the soft matter matrix.

[0054] Third implementation method:

[0055] The passive cochlear implant device corresponding to this embodiment is shown in the side view as follows. Figure 5 As shown, at this time, the protruding electrode portions on both sides of the piezoelectric material are distributed on different sides of the soft material matrix.

[0056] Fourth implementation method:

[0057] The passive cochlear implant device corresponding to this embodiment is shown in the top view as follows. Figure 6As shown, the projection of the soft matter matrix has a wedge-shaped shape (the wedge cross-sectional shape remains unchanged, and the cross-sectional area monotonically increases or decreases along the length of the matrix). This structure can assist the propagation of vibration waves inside the device and enhance the position encoding effect (low-frequency and high-frequency sound waves mainly excite different piezoelectric materials).

[0058] Fifth implementation method:

[0059] The passive cochlear implant device corresponding to this embodiment is shown in the top view as follows. Figure 7 As shown; compared to the fourth embodiment, the lengths of the piezoelectric material and electrodes within the soft material matrix also gradually change monotonically from a top-down perspective; the projected shape of the outer matrix can be wedge-shaped, or it can be a rectangle or any other arbitrary shape as described above. This configuration is beneficial for further enhancing the position encoding effect.

[0060] Because the substrate material is a flexible strip, the device can be naturally bent into a spiral shape. Figure 8 The diagram shows a top view of the device in the fifth embodiment, bent into a spiral shape. Unit 4 is the unit where the piezoelectric material 2 and electrode 3 are assembled. Depending on the required frequency coverage, the device can be bent from less than half a turn to 2.5 turns. The bending radius is close to the actual radius of the cochlear canal structure. Furthermore, to better maintain the spiral bending shape, the soft material matrix can be fabricated into a similar shape during the initial material molding process. Figure 8 The spiral shape makes the device more likely to maintain its spiral bending shape when it is not constrained.

[0061] Sixth implementation method:

[0062] The passive cochlear implant device corresponding to this embodiment is shown in the top view as follows. Figure 9 As shown; at this time, the distance between the piezoelectric materials and the shorter side length of the piezoelectric material and the corresponding electrode material monotonically increase or monotonically decrease along the direction of sound wave propagation. For example, x(n) = Aa n +Bn b The distance variation between piezoelectric materials (including corresponding electrode materials) is represented by +Cn+m. Here, x(n) represents the position of the piezoelectric material portion of the nth piezoelectric unit in the x-direction, a and b are any positive numbers greater than 1, and A, B, C, and m are any real numbers. The electrodes of adjacent units only need to be electrically insulated from each other and not in contact. For example, the sum of the widths of the nth piezoelectric material and the electrodes on both sides can be from |x(n+1)-x(n)| / 100 to 99×|x(n+1)-x(n)| / 100.

[0063] With the piezoelectric unit position x(n) = 1.02 n-1-1 (unit: millimeters), the height of the piezoelectric material and the electrodes on both sides is 1 mm, and the width is x(n) = 0.004 × 1.02. n-1 (Unit: millimeters), taking a total of 168 piezoelectric units as an example. Figures 14 to 16 The strain distribution of different parts of the device was simulated when different sound waves were incident on the device from one end. In the figure, the white (brighter) areas represent the locations with larger strains. The piezoelectric material at these locations is the frequency channel that is mainly activated at the current incident frequency. At this time, the piezoelectric material generates voltage to stimulate the spiral ganglion, which can realize the position-encoded stimulation of the sound wave at the current frequency. It can be seen that the sixth embodiment has a better frequency-selective focusing effect than the first embodiment.

[0064] Seventh implementation method:

[0065] The passive cochlear implant device corresponding to this embodiment is shown in the top view as follows. Figure 10 As shown; at this time, the lengths of the long sides of the piezoelectric material and the corresponding electrode material monotonically increase or monotonically decrease. For example, w(n) = Aa n +Bn b The length of the long side of the piezoelectric material (including the corresponding electrode material) is represented by +Cn+m. Here, w(n) represents the height of the nth piezoelectric material, a and b can be any positive numbers greater than 1, and A, B, C, and m are any real numbers.

[0066] With the piezoelectric unit position x(n) = 1.02 n-1 -1 (unit: millimeters), height w(n) of the piezoelectric material and electrodes on both sides = 0.04 × 1.02 n-1 (Unit: millimeters), width is x(n) = 0.004 × 1.02 n-1 (Unit: millimeters), taking a total of 168 piezoelectric units as an example. Figures 17 to 19 The stress distribution in various parts of the device was simulated when different sound waves were incident from one end onto the device (configured according to the seventh embodiment). The white (brighter) areas in the figure represent locations with higher stress. The piezoelectric material at these locations represents the frequency channels primarily activated at the current incident frequency. At this time, this portion of the piezoelectric material generates voltage to stimulate the spiral ganglion, completing the positional encoding stimulation of the sound wave at the current frequency. It is evident that the seventh embodiment exhibits better frequency-selective focusing effect compared to the first embodiment.

[0067] The above embodiments are merely examples. The soft material substrate, piezoelectric material, and electrode material can be flexibly adjusted according to actual conditions. The number and distribution of piezoelectric units, as well as the detailed dimensions of each component, can also be adjusted. As long as the passive cochlear implant device in this invention can generate a piezoelectric effect under sound waves with frequencies of 20-20000Hz, and the entire device can be implanted into the cochlea with the electrodes close to or in contact with the cochlear basilar membrane (of course, the voltage amplitude generated by the piezoelectric effect of the device should not be too large; considering that this device is a cochlear implant and needs to be housed in the human cochlea, under the size limitation of the cochlea, the voltage amplitude generated by normal volume will not exceed the safe voltage of the human body; this invention does not require a specific voltage amplitude because humans have strong learning abilities, and even a small voltage amplitude can activate the human auditory pathway without affecting the human brain's learning; for example, under the condition of 90 decibels of sound incidence, the voltage amplitude generated by the device can be 40mV to 4V). For example, the matrix in this invention can be a known soft material (also called a soft condensed matter), such as polymers, liquid crystals, colloids, foams, particulate matter, living system materials, solid-liquid mixtures, liquid-liquid mixtures, liquid-gas mixtures, etc., which are substances between solids and ideal fluids. Furthermore, the entire device can naturally bend into a spiral shape similar to the cochlear canal, inserted into the scala tympani 304 or scala vestibular 302 of the cochlea 301, naturally surrounding the cochlear axis. The exposed portion of the electrode 3 maintains a certain distance (within 1 mm) from the basilar membrane (including the membranes separating regions 302, 303, and 304) or directly contacts or penetrates the basilar membrane (e.g., ...). Figure 2 As shown, Figure 2 Due to viewing angle limitations, only the substrate material 1 and the electrode 3 in the piezoelectric unit 4 of the invention device can be observed in the cross section.

[0068] Furthermore, the device of the present invention can be fabricated using existing processes (such as photolithography), and the specific process parameters and condition settings can be adjusted according to actual size requirements.

[0069] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A passive cochlear implant device, characterized in that, include: A soft material matrix (1) and at least two piezoelectric units (4) located on or inside the matrix and distributed along the length of the matrix, wherein each piezoelectric unit (4) includes a piezoelectric material and electrodes located on both sides of the piezoelectric material and connected to the piezoelectric material. Any two adjacent piezoelectric units (4) do not contact each other, and each electrode is led out to the outside of the soft material matrix (1) and contacts or penetrates the cochlear basilar membrane. Different electrodes contact or penetrate different positions of the cochlear basilar membrane for local electrical stimulation to activate the spiral ganglion at the corresponding position below the cochlear basilar membrane.

2. The passive cochlear implant device as described in claim 1, characterized in that, The soft material matrix (1) is a flexible and deformable material; The piezoelectric material is a solid material exhibiting the piezoelectric effect; The electrode is an alloy electrode, a metal element electrode, an organic conductive material electrode, or an electrode made of any combination of the above materials.

3. The passive cochlear implant device as described in claim 2, characterized in that, The soft material matrix (1) is made of hydrogel, ionogel, organic gel, silicone rubber, polyurethane, thermoplastic elastomer or thermoplastic rubber; The piezoelectric material is a composite material of polyvinylidene fluoride and its copolymers, barium titanate, lead zirconate titanate, and the above materials. The electrodes are made of gold, silver, copper, or platinum.

4. The passive cochlear implant device as described in claim 1, characterized in that, The piezoelectric material in any one of the piezoelectric units (4) is in sheet form.

5. The passive cochlear implant device as described in claim 1, characterized in that, The soft material matrix (1) is elongated and can be bent into a shape that matches the human cochlea so as to be implanted into the human cochlea.

6. The passive cochlear implant device as described in claim 5, characterized in that, The soft matter matrix (1) is wedge-shaped and elongated.

7. The passive cochlear implant device as described in claim 5, characterized in that, The soft material matrix (1) has a length of 10-30 mm and a cross-sectional area of ​​0.01-4 mm² at any given cross-section. 2 .

8. The passive cochlear implant device as described in claim 1, characterized in that, The soft material matrix (1) is in a spiral-curved shape that matches the human cochlea.

9. The passive cochlear implant device as described in claim 1, characterized in that, The piezoelectric material is either completely encapsulated inside the soft material matrix (1), or adhered to the surface of the soft material matrix (1), or partially inserted into the soft material matrix (1).

10. The passive cochlear implant device as described in claim 1, characterized in that, Along the direction of sound wave transmission, the spacing between the piezoelectric material portions of two adjacent piezoelectric units (4) increases or decreases monotonically.

11. The passive cochlear implant device as described in claim 10, characterized in that, Let the direction of sound wave propagation be... x Orientation, each piezoelectric unit satisfies: in, x ( n ) indicates the first n The piezoelectric material portion of each piezoelectric unit is in x Position in the direction; a It is any positive number greater than 1; A , B , C , m Let be any real number.

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