A pseudo-neural electrode for precise cochlear nucleus stimulation

Abstract

The present invention discloses a pseudo-neural electrode for precise stimulation of the cochlear nucleus. It is made of a flexible material and includes at least one implanted electrode wire, which is provided with a number of electrode points. Each electrode point at least includes: an outer ring electrode and a central electrode. The outer ring electrode is arranged around the periphery of the central electrode to form a concentric circle structure, and the central electrode is electrically insulated from the outer ring electrode. The present invention uses a flexible material to fabricate micron-level electrodes, whose size and material are close to the target neurons, can penetrate deep into the cochlear nucleus, and can achieve precise stimulation of the target neurons, reducing the stimulation of non-target neurons. Moreover, the present invention also designs a micro Laplace concentric circle electrode structure, and any two or more of the electrode arrays can form a current loop, which can effectively inhibit the diffusion of the stimulation current, making the stimulation more efficient, achieving more precise and efficient stimulation of the neurons in the deep part of the cochlear nucleus that respond to different frequencies of sound, and at the same time improving the auditory reconstruction effect.

Description

Technical Field

[0001] The present invention belongs to the field of medical devices, and relates to an implantable electrode, specifically to a pseudo-neural electrode for precise stimulation of the cochlear nucleus. Background Art

[0002] Artificial auditory brainstem implantation is the only method for treating severe or more profound deafness accompanied by severe cochlear and / or cochlear nerve lesions. Its principle is to implant an electrode at the central cochlear nucleus to generate hearing. However, since the cochlear nucleus has multiple histological and functional partitions, mainly composed of nerve cells with different electrophysiological characteristics; and there are neuron distributions that respond to different frequencies of sound from the surface to the depth of the cochlear nucleus, all of which increase the difficulty of generating meaningful hearing through surface electrical stimulation of the cochlear nucleus.

[0003] As Figure 1 shown, the currently clinically applied plate-shaped electrode 1' only stimulates the dorsal cochlear nucleus (DCN) part, and its shape and texture (hardness) do not exactly match the brain tissue at the stimulation site, and it cannot fit well with the surface curvature of the cochlear nucleus to form a good electrode-neural interface, resulting in the divergence of the stimulation current; and the frequency distribution characteristics deep in the cochlear nucleus are not fully utilized, resulting in an unsatisfactory auditory reconstruction effect for patients with auditory brainstem implantation at the present stage. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem of the divergence of the stimulation current existing in the existing electrodes. By providing a flexible electrode wire and implanting it inside the cochlear nucleus, and setting electrode points on the electrode wire, the divergence of the stimulation current is reduced.

[0005] To achieve the above purpose, the present invention provides a pseudo-neural electrode for precise stimulation of the cochlear nucleus, which is connected to a stimulation control device through a wire. The characteristics of the pseudo-neural electrode are that it is made of a flexible material and includes at least one implantable electrode wire. A plurality of electrode points are arranged on the implantable electrode wire. Each electrode point at least includes: an outer ring electrode and a central electrode. The outer ring electrode is arranged around the periphery of the central electrode to form a concentric circle structure, and the central electrode is electrically insulated from the outer ring electrode.

[0006] Optionally, the areas of the outer ring electrode and the central electrode are equal or substantially equal.

[0007] Optionally, each of the outer ring electrodes and the central electrodes is respectively led out through an electrode wire and electrically connected to the stimulation control device to form independent control or combined control of each electrode point. Further, any two or more electrodes can form a current loop to achieve multi-polar stimulation such as BP and TP, and even virtual channel stimulation.

[0008] Optionally, the outer diameter of the outer ring electrode is not greater than 300 μm.

[0009] Optionally, 6 - 40 electrode points are arranged on each implanted electrode wire, preferably 7 - 10 electrode points.

[0010] Optionally, the distance between adjacent electrode points is at least twice the outer diameter of the outer ring electrode.

[0011] Optionally, the distance between the distal electrode point and the distal end of the implanted electrode wire is 25 - 500 μm, and the distance between adjacent electrode points is 50 - 500 μm.

[0012] Optionally, any two or more electrode points on each implanted electrode wire form a current loop.

[0013] Optionally, the width of the implanted electrode wire is at the micron level.

[0014] Optionally, the surface of the electrode points is modified with Platinum black or PEDOT, etc.

[0015] Optionally, the flexible material of the electrode wire is an organic polymer material, such as any one or any combination of polyimide, parylene, polydimethylsiloxane, SU - 8, and carbon nanomaterials.

[0016] Optionally, the pseudo - neural electrode includes at least one group of implanted electrode wires, and each group of implanted electrode wires is composed of a first electrode wire and a second electrode wire, and the first electrode wire is longer than the second electrode wire.

[0017] Optionally, the pseudo - neural electrode includes 3 groups of implanted electrode wires, which are respectively implanted into the AVCN, PVCN, and / or DCN regions according to the corresponding cochlear nucleus frequency distribution characteristics.

[0018] Advantages of the present invention:

[0019] 1) By arranging electrode points with a concentric circle structure on the flexible electrode wire, the divergence of the stimulating current is restricted; further, by controlling the areas of the central electrode and the outer ring electrode to be equal or substantially equal, the anti - interference ability of the electrode is enhanced.

[0020] 2) By minimizing the volume of the implanted device (i.e., the implanted electrode wire) as much as possible, simulating the neuron morphology (cell body 10 - 20 μm), and setting the electrode points and the implanted electrode wire to the micron level close to the neuron size, it is easy to approach the neurons deep in the cochlear nucleus to achieve precise stimulation; and it can cooperate with the concentric circle structure electrode design of the electrode points to further restrict the current divergence, reduce the stimulation side effects, improve the stimulation efficiency, and achieve precise and efficient stimulation of the part to be stimulated.

[0021] 3) Adopt a flexible material with a texture close to the size of neurons, and try to simulate the cranial nerve parameters as much as possible. It can achieve a shape and texture that are as close as possible to the brain tissue at the stimulation site, reduce the tissue reaction after being implanted into the cochlear nucleus, and maintain the long-term stability of the electrode-neural interface.

[0022] 4) The flexible material and the neuron-like specification design can also improve the long-term tissue reaction of the brain tissue to the implanted device, reduce the loss of neurons (such as apoptosis) around the implant, and reduce the encapsulation of the electrode by fibrous tissue in the long term, ensuring the long-term stability of the electrode-neural interface and enhancing the long-term stimulation effect. Brief Description of the Drawings

[0023] Figure 1 It is a schematic diagram of the distribution of the auditory nerve in the cochlear nucleus.

[0024] Figure 2 It is a schematic structural diagram of a pseudo-neural electrode for precise stimulation of the cochlear nucleus according to the present invention.

[0025] Figure 3 It is a schematic diagram for comparing the current diffusion of the Laplace concentric circle electrode and the conventional electrode of the present invention.

[0026] Figure 4 It is a schematic diagram of the local electrode points on the implanted electrode wire of the present invention.

[0027] Figure 5 It is a schematic diagram of the wire routing of the electrode points on the implanted electrode wire of the present invention.

[0028] Figure 6 It is a schematic comparison diagram of the principle of the monopolar, bipolar, and tripolar stimulation current circuits.

[0029] Reference Signs in the Drawings:

[0030] Implanted electrode wire 10

[0031] First electrode wire 101

[0032] Second electrode wire 102

[0033] Electrode point 11

[0034] Central electrode 111

[0035] Outer ring electrode 112

[0036] Wire 2. Detailed Description of the Embodiment

[0037] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0039] As used herein, "distal end" refers to the end away from the operator, and "proximal end" refers to the end close to the operator.

[0040] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] As Figure 2 shown, the present invention provides a pseudo-neural electrode for precise stimulation of the cochlear nucleus, which is connected to a stimulation control device (not shown in the figure) through a wire 2. The pseudo-neural electrode includes at least one implanted electrode wire 10, and a plurality of electrode points 11 are arranged on the electrode wire.

[0042] In the prior art, the implanted electrode is prone to the divergence of the stimulation current. As Figure 3 shown in a of Figure 3 , it results in inaccurate and inefficient stimulation. To this end, the present application utilizes the Laplace principle to design the electrode points as a concentric circle structure, which can effectively reduce the current divergence, as

[0043] shown in b of Figure 4As shown, in order to reduce the divergence of the stimulating current, based on the Laplace principle, the electrode point 11 of the present invention is designed to include a set of concentric circle electrodes, that is, at least including a central electrode 111 and an outer ring electrode 112 arranged around the central electrode. The central electrode 111 and the outer ring electrode 112 are electrically isolated from each other. In this example, electrical isolation is achieved by setting a certain gap, and they are respectively led out through electrode wires and connected to the stimulating control device, so that each electrode point can be controlled separately or multiple electrode points can be controlled jointly. In this example, as Figure 5 shown (the dotted line represents the schematic of the electrode wire connected to the electrode point inside the electrode, and the left end is the distribution schematic of the electrode wire when it outputs at the end), the central electrode 111 is the negative electrode, the wire extends from the central part to the stimulating control device, and the outer ring electrode 112 is the positive electrode, and the wire extends from both sides of the outer ring electrode to the stimulating control device.

[0044] In some embodiments, any two or more electrode points (including the central electrode 111 or the outer ring electrode 112) on each electrode wire can form a current loop to achieve multi-pole stimulation such as BP (bipolar) and TP (tripolar), and even virtual channel stimulation. The principle of the stimulating current loop is as Figure 6 shown. This setting does not change the existing electrode wiring, which is similar to a series connection. It can be understood that the way the current flows in and out provided by the stimulating control device has changed, that is, it is controlled by changing the settings of the stimulating control device. The current loop formed by a pair of central electrodes and peripheral electrodes is extended to any two or even more non-concentric combinations of central-central electrodes, peripheral-peripheral electrodes or central-peripheral electrodes to form a current loop. The stimulation range of such a loop is larger than that of a single Laplace electrode. At the same time, forming a loop between two electrodes also restricts the current divergence to a certain extent, and can stimulate a larger area range more efficiently and with a certain degree of accuracy in practical applications; moreover, to a certain extent, it enriches the stimulation mode, which is beneficial to more detailed characterization of different external sound information by applying different combinations of stimulating electrodes.

[0045] In some embodiments, the present invention also controls the inner and outer diameters of the central electrode 111 and the outer ring electrode 112 to keep the areas of the central electrode 111 and the outer ring electrode 112 consistent, so that the impedances of the two electrodes are the same, the circuit symmetry is good, and the anti-interference ability is enhanced.

[0046] Existing surface electrodes cannot form precise and efficient stimulation for deep neurons. Moreover, the stimulating current of surface electrodes is relatively large, which is easy to activate non-target neurons.

[0047] In order to achieve precise and efficient stimulation of the site to be stimulated, the present invention designs the electrode points to be small enough to precisely stimulate the target neurons and avoid misactivation of non-target neurons. The outer diameter of the electrode point 11 designed in the present invention is not greater than 300 μm, and in some embodiments, the outer diameter is not greater than 25 μm. Such a small size enables the electrode wire 10 to be implanted closer to the target neurons inside the cochlear nucleus, achieving precise stimulation, and can cooperate with the concentric circle structure electrode design of the electrode point 11 to further limit the current divergence, reduce the stimulation side effects, and achieve the purpose of precision and efficiency.

[0048] The small size of the electrode points not only facilitates the precise stimulation of the electrodes implanted inside the cochlear nucleus, but also enables the number of electrode points to be increased as much as possible.

[0049] The existing number of electrodes in clinical practice is generally 21, far less than the number of neurons in the neural nucleus. In theory, increasing the number of electrodes for precise stimulation as much as possible can improve the stimulation resolution and the reconstruction effect, but at the same time, the possible current interference caused by too small electrode spacing needs to be considered. In the present invention, in order to make the total number of electrodes far exceed the existing electrodes, the number of electrode points on each electrode wire is controlled to be more than 6, such as 6 - 40, and 7 - 10 can be selected (for example, if 6 electrode wires are used, the number of electrode points reaches more than 42). However, increasing the number of electrode points is also likely to cause crosstalk. To prevent crosstalk, the present application controls the distance between adjacent electrode points 11 to be at least 2 times or more of the outer diameter of the electrode point 11.

[0050] Since the impedance will increase after the electrode points are reduced, affecting the electrode stimulation and recording effects, to solve this technical problem, the present invention also designs surface modification treatment of the electrodes, such as using Platinum black or PEDOT to modify the surface of the electrode points to optimize the electrochemical properties such as the electrode resistance and charge-discharge performance, ensuring the stimulation efficiency to a certain extent and making the stimulation division areas of each electrode more precise.

[0051] In some embodiments, the steps of using Platinum black to modify the Pt electrode points include: ① putting the electrode points to be modified with Platinum black into the sputtering chamber, using Pt as the target, and using a vacuum pump and a molecular pump to pump the vacuum in the chamber to 2 - 4×10 -4 Pascal; ② introducing argon gas, energizing to ionize the argon gas and generate plasma, and adjusting the appropriate pressure; ③ introducing oxygen gas, adjusting the pressure, opening the baffle, and starting the reactive sputtering process; ④ turning off the current and closing the baffle to end the reactive sputtering process.

[0052] In some embodiments, using Au / PIN-5NO 2 / PEDOT to modify the Au electrode points, the steps include:

[0053] (1) Electrochemical deposition is performed on an electrochemical workstation, in which a platinum sheet electrode is provided in a glass cell as a counter electrode, a saturated calomel electrode (SCE) is provided as a reference electrode, and the electrode to be modified is provided as a working electrode;

[0054] (2) PIN-5NO 2 Electrochemical deposition of acetonitrile with 0.05 mol / L 5-nitroindole and 0.1 mol / L lithium perchlorate (LiClO 4 ), potential deposition is performed in a potential range of -0.1-1.4 V;

[0055] (3) The electrochemical deposition of PEDOT was carried out in acetonitrile using 0.05 mol / L EODT and 0.1 mol / L LiClO 4 The deposition was carried out at a constant potential of 1.4 V and a deposition time of 1-2 min. After each deposition process, the electrode was cleaned in acetonitrile and water for 5 min.

[0056] The precise stimulation of the present invention is also reflected in synchronous stimulation. Each implanted electrode wire 10 or each electrode point 11 can be independently controlled or jointly controlled. Under the regulation of a stimulation control device (such as a sound processor), different discharge stimulation modes of different electrode points can be realized according to actual needs.

[0057] The neuromimetic electrode of the present invention is flexible, and its parameters simulate the parameters of brain nerves as much as possible, so that its shape and texture can be matched as completely as possible with the brain tissue to be stimulated, and it can better fit the curvature of the surface of the cochlear nucleus, reduce tissue reaction after implantation inside the cochlear nucleus, and maintain long-term stability of the electrode-nerve interface.

[0058] The neuromimetic electrode of the present invention is prepared by a flexible material. The flexible material may be an organic polymer material, such as polyimide (PI), polyparaxylene (Parylene), polydimethylsiloxane (PDMS), SU-8, and carbon nanomaterials. The principle of selecting the flexible material is to select the material currently approved for intracranial implantation, and to screen the Young's modulus, bending hardness parameters, etc. of the electrode made of the material, and try to select the material close to the parameters of brain tissue.

[0059] Current research results show that fiber wrapping around the implant and the death of surrounding target neurons are common problems with intracranial implants, and are also important reasons for the poor long-term function of implanted devices. Because fiber wrapping causes the distance between the electrode and the target neuron (cell body 10-20μm) to continue to increase, the level of electrical stimulation needs to be further increased to effectively activate the target neuron. However, the increased level of electrical stimulation may cause current divergence. In addition, the death of target neurons around the electrode also leads to the failure of the electrode and the target neuron to form a good interface, which in turn leads to poor stimulation efficiency.

[0060] The flexible implantable electrode with neuron-sized dimensions of the present invention can, to a certain extent, improve the above problems. The flexible material and neuron-like specifications reduce the long-term fibrous tissue encapsulation of the electrode and the apoptosis of surrounding neurons, ensuring the long-term stability of the electrode-neural interface.

[0061] In order to achieve the purpose of generating meaningful hearing through surface electrical stimulation at different frequency sites and achieve better hearing reconstruction effects, the present invention also adopts a long and short paired implantable electrode wire design based on the distribution characteristics of the auditory nerve in the cochlear nucleus, and implants them into the anterior ventral cochlear nucleus (AVCN) and the posterior ventral cochlear nucleus (PVCN) / dorsal cochlear nucleus (DCN) directions respectively, for simulating the natural course of the auditory nerve, so as to more precisely and efficiently stimulate the neurons in the deep part of the cochlear nucleus that respond to different frequency sounds, and at the same time improve the hearing reconstruction effect.

[0062] In some embodiments, the pseudo-neural electrode includes at least one set of implantable electrode wires 10. Each set of electrode wires is composed of a first electrode wire 101 and a second electrode wire 102, and the first electrode wire 101 is longer than the second electrode wire 102. Generally, the length of the first electrode wire 101 can be 1.5 - 3 mm, and the length of the second electrode wire 102 can be 0.5 - 1 mm. In theory, the number of the implantable electrode wires may be 1 - 5 groups. Experiments have found that the coverage of the functional areas of the relevant neural nuclei by 4 electrode wires (2 groups) is limited; 8 (4 groups) or 10 (5 groups) and more may not be all implanted into the narrow cochlear nucleus area, and implanting a large number of electrodes in the cochlear nucleus may not further improve the hearing reconstruction effect, and may also hinder the blood circulation of local neurons due to excessive implantation, resulting in a decline in the hearing reconstruction effect. In this example, the pseudo-neural electrode adopts 3 groups of implantable electrode wires 10, which are respectively implanted into the AVCN and PVCN / DCN sites to simultaneously stimulate or precisely stimulate the neurons that respond to different frequency sounds, so as to achieve the purpose of efficiently improving the hearing reconstruction effect.

[0063] The pseudo-neural electrode of the present invention is micron-sized, with specifications close to the neuron level, which can effectively reduce long-term tissue reactions. The implanted electrode wire 10 has dimensions (such as width, thickness, and electrode point size) in the micron range, and the width of the implanted electrode wire 10 is less than 500 um. The distal electrode point 11 is at a certain distance from the distal end of the implanted electrode wire 10 to prevent the terminal electrode point from directly breaking through the brain tissue during the implantation process, playing a certain protective role. This distance can be 25 - 500 μm, and 25 - 50 μm can be selected to minimize the size as much as possible; the distance between adjacent electrode points is 50 - 500 μm, and 50 - 100 μm can be selected to minimize the size as much as possible. By the physical space distance between the surface electrode points, the possible current interference can be avoided. In this example, the distance from the terminal electrode point of the short electrode (i.e., the second electrode wire) to the end of the short electrode wire is 25 um, and the distance between two adjacent electrode points is 50 um; the distance from the terminal electrode point of the long electrode (i.e., the first electrode wire) to the end of the long electrode wire is 50 um, and the distance between two adjacent electrode points is 100 um.

[0064] In summary, based on a long-term effective electrode-neural interface, a greatly increased number of electrode points, and precise stimulation current, the auditory reconstruction effect is improved.

[0065] Embodiment

[0066] In this example, six implanted electrode wires are used, which are respectively implanted into the cochlear nucleus regions responsible for low-frequency, mid-frequency, and high-frequency sound processing. One long and one short electrode wire are implanted in each region (for the distribution, see Figure 1 ). Usually, the diameter of the electrode points of clinical products is 700 μm. In this example, the outer diameter of the electrode points is 25 μm, the total diameter of all the wires together does not exceed 1 mm, and the total length is 150 mm. The manufacturing method is as follows:

[0067] 1. Select silicon wafers (or glass) with a thickness of 300 - 500 μm, put them into acetone, ethanol, and deionized water respectively, ultrasonically clean for 5 minutes, dry with a nitrogen gun, and dry in an oven at 120 °C for 1 - 2 h for standby;

[0068] 2. Sputter metal Al on the cleaned silicon wafer as a sacrificial layer;

[0069] 3. Deposit 1 - 2 μm thick Parylene C by chemical vapor deposition or spin-coat 1 - 2 μm thick PI on the sacrificial layer;

[0070] 4. Use sputtering, photolithography, and ion beam etching processes to form a patterned central electrode circuit layer, and sequentially sputter a layer of Cr (30 nm) and a layer of Au (100 - 200 nm) metal thin film layers;

[0071] 5. Deposit a 1 μm insulating layer of Parylene C or spin-coat 1 μm of PI;

[0072] 6. Etch Parylene C or PI on the central electrode connection line to expose the electrode connection points;

[0073] 7. Use sputtering, photolithography, and ion beam etching processes to form the patterned central electrode, ring electrode, and their circuit lines, and sequentially sputter a layer of Cr (30 nm) and a layer of Au (100 - 200 nm) metal thin film layers;

[0074] 8. Deposit 1 - 2 μm of insulating layer Parylene C or spin - coat 1 - 2 μm of PI;

[0075] 9. Etch Parylene C or PI on the central electrode, ring electrode points, and bonding pads to expose the electrode point areas, and the exposed bonding pad areas are used to connect to the backend stimulation control device;

[0076] 10. Etch the flexible electrode on the entire sample into the shape along the designed frame;

[0077] 11. Electrolyze the sacrificial layer metal Al to release the flexible electrode and obtain the pseudo - neural electrode of the present invention.

[0078] The usage method of the pseudo - neural electrode of the present invention is as follows:

[0079] S1, Heat and melt polyethylene glycol (PEG);

[0080] S2, Dip the surface of the implantation fine needle / wire with an appropriate amount of PEG, wait for natural cooling, and use the fine needle / wire to adhere to the implantation electrode wire of the present invention for guiding implantation; or, it is also possible to directly apply the implantation electrode wire to dip with PEG and perform implantation after cooling and hardening;

[0081] S3, The surgical operator implants the short electrode wire in the AVCN direction and the long electrode wire in the PVCN / DCN direction based on what is seen during the operation;

[0082] S4, After implantation, pause for a moment and wait for part of the PEG to dissolve (it will be metabolized and degraded after dissolution), then withdraw the implantation fine needle / wire at this time and leave the electrode wire at the target implantation position;

[0083] S5, Perform effective stimulation through the stimulation control device connected to the tail of the wire, and specific electrode wires or electrode points can be stimulated as needed.

[0084] In summary, the present invention uses flexible materials to fabricate micron-scale electrodes. Their size and material are close to those of the target neurons, enabling them to penetrate deep into the cochlear nucleus, achieving precise stimulation of the target neurons and avoiding the stimulation of non-target neurons. Moreover, the present invention also designs a micro Laplacian concentric circle electrode structure, which can effectively suppress the diffusion of the stimulation current, making the stimulation more efficient, realizing more precise and efficient stimulation of the neurons in the deep part of the cochlear nucleus that respond to different frequencies of sound, and simultaneously improving the effect of auditory reconstruction.

[0085] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. After those skilled in the art have read the above content, various modifications and alternatives to the present invention will be obvious. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims

1. A pseudo-neural electrode for precise stimulation of the cochlear nucleus, which is connected to a stimulation control device through a wire. It is characterized in that the pseudo-neural electrode is made of a flexible material and includes at least one implanted electrode wire. A number of electrode points are arranged on the implanted electrode wire. Each electrode point includes at least: an outer ring electrode and a central electrode. The outer ring electrode is arranged around the periphery of the central electrode to form a concentric circle structure. The central electrode is electrically isolated from the outer ring electrode; the areas of the outer ring electrode and the central electrode are equal or substantially equal; the outer diameter of the outer ring electrode is not greater than 300 μm; each of the outer ring electrodes and the central electrodes is led out through an electrode wire and electrically connected to the stimulation control device to form the control of each electrode point; the distance between adjacent electrode points is at least twice the outer diameter of the outer ring electrode.

2. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 1, It is characterized in that 6 to 40 electrode points are arranged on each implanted electrode wire.

3. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 1, It is characterized in that the distance between the distal electrode point and the distal end of the implanted electrode wire is 25 μm - 500 μm, and the distance between adjacent electrode points is 50 μm - 500 μm.

4. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 1, It is characterized in that any two or more electrode points on each implanted electrode wire form a current loop.

5. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 4, It is characterized in that the width of the implanted electrode wire is in the micron range.

6. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 1, It is characterized in that the surface of the electrode point is modified by Platinum black or PEDOT.

7. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 1, It is characterized in that the flexible material of the electrode wire is an organic polymer material.

8. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to any one of claims 1-7, It is characterized in that the pseudo-neural electrode includes at least one group of implanted electrode wires. Each group of implanted electrode wires is composed of a first electrode wire and a second electrode wire, and the first electrode wire is longer than the second electrode wire.

9. The pseudo-neural electrode for precise stimulation of the cochlear nucleus according to claim 8, It is characterized in that the pseudo-neural electrode includes 3 groups of implanted electrode wires, which are used to be implanted into the AVCN, PVCN and / or DCN parts respectively according to the corresponding cochlear nucleus frequency distribution characteristics.

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