Artificial cochlea electrode implant and application thereof

Abstract

The invention relates to an artificial cochlea electrode implant and application thereof, and belongs to the technical field of surgical medical equipment. The artificial cochlea electrode implant comprises a stimulating electrode part and a connector connected with the stimulating electrode part; the stimulating electrode part comprises a first electrode wire and a plurality of second electrode wires which are connected with the connector, an electrode array arranged at the end of the first electrode wire, and a common electrode arranged at the end of the second electrode wire; the first electrode wire and the second electrode wire are respectively wound with an insulating tape, the electrode array and the common electrode are exposed, the electrode array comprises a plurality of semi-ring electrodes which are arranged at the end of the first electrode wire side by side, and one side of the end of the first electrode wire is provided with a flexible insulating suture which transversely penetrates through the semi-ring electrodes. The artificial cochlea electrode implant can be more easily and stably implanted into the cochlea of a small rodent experimental animal, and auditory nerve response can be measured and electrical stimulation can be carried out in the state that the small rodent experimental animal is sober and freely moves.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical medical equipment, and in particular to an artificial cochlear electrode implant and application thereof. Background Art

[0002] Cochlear implants convert sound into electrical signals and stimulate the peripheral auditory nerves through direct electrical stimulation, thereby reconstructing hearing function. As cochlear implant technology gradually improves, the clinical indications for cochlear implants are gradually broadening, and more people with hearing impairments are beginning to benefit from this technology.

[0003] Although cochlear implant technology has restored some hearing to many people, there is still a big difference between artificial hearing and natural hearing. In addition, the diversity of hearing impairments also leads to differences in the effects of cochlear implants in different patients, and cochlear implant technology still needs further improvement and research. In recent years, with the maturity of gene editing technologies such as CRISPR / Cas9, more and more gene-edited mice have been used to simulate hearing impairments in different populations. Therefore, cochlear implant electrodes suitable for small rodents such as mice are needed to combine gene-edited mice to further explore the effects and functions of peripheral electrical stimulation on different peripheral and central disease states, in order to explore electrical stimulation patterns that are more suitable for each patient.

[0004] Previous cochlear implants for animals were large in size and weight. Although they can be used in guinea pigs and rats with larger cochleas and round windows, the inner ear structures of small rodents such as mice are smaller and more delicate, and the size and surgical requirements of the implants are higher. Implants designed specifically for mice will reduce the difficulty of animal surgery and the sustainability of the implants, achieving short-term and long-term implant effects. Summary of the invention

[0005] The purpose of the present invention is to adapt to the inner ear structure of small rodents such as mice, thereby providing a cochlear electrode implant and its application.

[0006] The purpose of the present invention can be achieved by the following technical solutions: One of the technical solutions of the present invention is to provide a cochlear implant electrode, comprising: a stimulation electrode portion, a connector connected to the stimulation electrode portion, The stimulation electrode part includes a first electrode wire and a plurality of second electrode wires connected to the connector, an electrode array arranged at the end of the first electrode wire, and a common electrode arranged at the end of the second electrode wire. The first electrode wire and the second electrode wire are each wrapped with insulating tape and the electrode array and the common electrode are exposed. The electrode array includes a plurality of semi-ring electrodes arranged side by side at the end of the first electrode wire, and a flexible insulating suture is provided on one side of the end of the first electrode wire to cross the semi-ring electrode.

[0007] In some specific embodiments, the diameter of the flexible insulating suture is 0.05 mm.

[0008] In some specific embodiments, there are three semi-ring electrodes with a diameter of 0.25 mm, a spacing of 0.5 mm, a width of 0.3 mm, and a maximum distance from the semi-ring electrode to the end of the first electrode wire is 2.1 mm.

[0009] In some specific embodiments, an insulating tape is gradually wound around the first electrode wire at 1 cm behind the electrode array, so that the diameter of the first electrode wire after winding is 0.4-0.5 mm, and the winding length of the insulating tape is 3-4 cm.

[0010] In some specific embodiments, the length of the stimulation electrode portion is 5 to 6 cm.

[0011] In some specific embodiments, the first electrode wire and the plurality of second electrode wires are connected to the connector via a flexible flat cable, and the length of the flexible flat cable is 10 cm.

[0012] In some specific embodiments, the mass of the cochlear implant electrode is 0.5-0.6 g.

[0013] In some specific embodiments, two second electrode wires are provided, and two common electrodes are provided.

[0014] In some specific embodiments, a latex fixing strip with a length of 0.3 mm is symmetrically provided on the first electrode wire at a distance of 2 cm from the electrode array.

[0015] A second technical solution of the present invention is to provide an application of a cochlear electrode implant as described in one of the above technical solutions, wherein the cochlear electrode implant is used to be implanted into the cochlea of ​​a small rodent experimental animal to measure the auditory nerve response and perform electrical stimulation when the small rodent experimental animal is awake and freely moving.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) Since the anatomical structure of the mouse cochlea is quite different from that of the traditional implant model guinea pig, and there is a stapedial artery running below the round window, the difficulty of implantation and the material requirements are very high. The cochlear implant electrode of the present invention has the characteristics of small size and mass, and can be implanted in the mouse cochlea more easily and stably. The implant of the present invention adopts the posterior edge of the sternocleidomastoid muscle approach on the mouse cochlear implantation path, only opens a small part above the round window of the auditory bulla, bypasses all the large arteries and important structures, and can preserve the hearing of the mouse to the greatest extent. The electrode used in the present invention causes minimal damage to the stapedial artery running below the round window, which greatly reduces the probability of damage to the artery during the implantation process and electrical stimulation process, and improves the survival rate of the mouse.

[0017] (2) The cochlear implant electrode of the present invention reduces the diameter of the stimulation electrode part and increases its durability and toughness. The present invention replaces the traditional circular electrode with a semi-ring electrode. In addition to reducing the diameter, it also increases durability, increases the adhesion between the electrode and the flexible insulating suture, and reduces the possibility of electrode damage and detachment during and after surgery. The biggest problem with electrodes with extremely small diameters is that as the diameter decreases, the toughness of the electrode will decrease, which will increase the failure rate of the implant. The present invention can greatly improve the success rate of the implant by combining flexible insulating sutures with semi-ring electrodes, almost reaching the success rate and postoperative survival rate of traditional guinea pig cochlear implants.

[0018] (3) The cochlear implant electrode of the present invention can be connected to a stimulation decoder outside the animal's body through a connector, so as to measure the auditory nerve response and perform electrical stimulation while the mouse is awake and moving freely.

[0019] (4) The miniaturization of the cochlear implant electrode of the present invention is a great advancement, which makes cochlear implantation in mice possible and can be used in conjunction with other scientific research. Therefore, the cochlear implant electrode implant provided by the present invention can be widely applied to a variety of gene-edited mice to study cochlear implantation and its effects in different disease scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the first electrode wire and the electrode array of the present invention.

[0022] Figure 3 Schematic diagram of the structure of the electrode array of the present invention.

[0023] Figure 4 Schematic diagram of surgical location and anatomy for mouse implantation.

[0024] Figure 5It is another partial structural schematic diagram of the present invention.

[0025] The following are marked in the figure: 101 is the electrode array, 102 is the common electrode, 2 is the stimulation electrode part, 301 is the first electrode wire, 302 is the second electrode wire, 4 is the soft flat cable, 5 is the semi-ring electrode, 6 is the flexible insulating suture, 7 is the insulating tape, 8 is the surgical incision position, 9 is the mastoid process, 10 is the facial nerve, 11 is the stapedial artery, 12 is the round window, 13 is the auditory bulla, and 14 is the latex fixing strip. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In conjunction with the accompanying drawings, some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0029] In the following embodiments, unless otherwise specified, functional components or structures are conventional components or conventional structures used in the art to achieve corresponding functions.

[0030] Example 1 like Figures 1 to 3 As shown, a cochlear implant electrode body comprises: a stimulation electrode part 2, and a connector connected to the stimulation electrode part 2. The stimulation electrode part 2 comprises a first electrode wire 301 and two second electrode wires 302 connected to the connector via a flexible flat cable 4, an electrode array 101 arranged at the end of the first electrode wire 301, and a common electrode 102 arranged at the end of the second electrode wire 302. The first electrode wire 301 and the second electrode wire 302 are each wrapped with an insulating tape 7 to expose the electrode array 101 and the common electrode 102. The electrode array 101 comprises three semi-ring electrodes arranged side by side at the end of the first electrode wire 301. The insulating tape 7 can be made of silicone tape, and silicone material rarely causes rejection reaction when implanted in an animal.

[0031] Due to the special anatomical structure of the cochlea of ​​small rodents such as mice, there is a stapedial artery below the round window, and the implant difficulty and material requirements for the cochlear implant electrode are very high. Based on the premise that the mouse is small and light, the diameter of the electrode is reduced to increase the implantation success rate, but the biggest problem in the electrode with a very small diameter is that the toughness of the electrode will decrease as the diameter decreases. Since the round window diameter of the mouse is about 0.3 mm, after practice, the toughness of the electrode head will decrease sharply after the electrode diameter is less than 0.5 mm. Simply reducing the electrode diameter cannot meet the requirements of implanting mice and increase the failure rate of implantation. Therefore, in this embodiment: a flexible insulating suture 6 that crosses the semi-ring electrode 5 is provided on one side of the end of the first electrode wire 301 to increase the toughness and tolerance of the electrode array 101, reduce the resistance during the implantation process, and make it more smoothly implanted into the mouse round window, reducing the possibility of damage and falling off of the electrode array 101 during and after the operation. Preferably, the flexible insulating suture 6 is a surgical suture and is wrapped with silicone tape, and the overall diameter is 0.05 mm. Surgical sutures can be made of nylon or polypropylene, or other non-metallic threads to improve toughness and strength; the silicone material of silicone tape is less likely to cause rejection reactions when implanted in animals.

[0032] The arrangement of the three semi-ring electrodes 5 in the electrode array 101 is as follows: the diameter R of the semi-ring electrode 5 is 0.25 mm, and the width h1 is 0.3 mm. The present invention reduces the diameter of the semi-ring electrode 5 as much as possible, providing the possibility for round window implantation in small rodents. The three semi-ring electrodes 5 are not connected, and the spacing h2 therebetween is 0.5 mm. The farthest distance h3 from the semi-ring electrode 5 to the end of the first electrode wire 301 is 2.1 mm, which is basically the same as the length of the cochlear basal turn of a normal adult mouse. The common electrode 102 is a conventional electrode in the art.

[0033] The insulating tape 7 is gradually wound around the first electrode wire 301 at 1 cm behind the electrode array 101, so that the diameter of the wound first electrode wire 301 is 0.4-0.5 mm, and the winding length of the insulating tape 7 is 3-4 cm, so as to achieve the effect of stabilizing the electrode position after implantation, that is, after the electrode is wound into the auditory bulla, its movement in the tissue is reduced by increasing its diameter, so as to achieve the purpose of long-term electrical stimulation while the mouse is free to move. And the silicone material rarely has a rejection reaction when implanted in the animal body.

[0034] The length of the stimulation electrode part 2 is 5 to 6 cm.

[0035] One first electrode wire 301 and two second electrode wires 302 are connected to the connector through a soft flat cable 4. The length of the soft flat cable 4 is 10 cm, and a silicone tape is wrapped around the periphery of the connection. The silicone material rarely causes rejection reaction in the implanted animal. Both the soft flat cable 4 and the connector are commercially available. As a preferred embodiment, the specification of the soft flat cable 4 is 0.5×6P×100 MM. The connector can be flexibly adjusted according to the range of mouse activities and the size of the special mouse cage. The main purpose of using the connector is to separate it from the decoder and connect the external decoder when needed. On the one hand, the decoder can be reused to reduce costs, and on the other hand, the weight and volume carried by the animal can be reduced, which helps to reduce trauma and infection, and facilitates the animal's self-activity. At the same time, the use of the soft flat cable 4 and the connector can make the joint mass smaller than the previous ones, which is more suitable for mice with more flexible activities, and can reduce the probability of damage to the electrode due to the frequent activities of the experimental animals. The mass of the cochlear implant electrode in this embodiment is 0.5~0.6g.

[0036] Example 2 Based on the cochlear implant electrode of Example 1, this example provides an application of the cochlear implant electrode, wherein the cochlear implant electrode is implanted into the cochlea of ​​a small rodent experimental animal.

[0037] The following implantation method may be referred to, including the following steps: After skin preparation of mice weighing 20 to 30 g, an incision of approximately 1 × 1 cm was made behind the ear. Figure 4 The surgical incision position 8 is shown, the sternocleidomastoid muscle is positioned with the post-auricular nerve as a marker, the muscle fascia tissue is separated along the posterior edge of the sternocleidomastoid muscle to expose the auditory bulla, the mastoid process 9, the facial nerve 10, and the posterior belly of the digastric muscle are used as marks to open the auditory bulla and expose the round window, a 0.3 mm drill is used to open the auditory bulla in the anterior-upward direction, and care is taken not to damage the stapedial artery 11 below the round window, the stapedial artery 11 is used as a marker to expand the opening area of ​​the auditory bulla upward to fully expose the round window 12, the round window membrane is punctured with a 0.1 mm platinum wire, and the electrode array 101 is pushed into the cochlea along the direction of the vestibular scala, the round window is filled with mouse muscle or fascia tissue to prevent the continued outflow of lymph, the remaining electrode wire is wrapped around the auditory bulla for fixation, and the auditory bulla gap is closed with dental bone cement, and then the common electrode 102 is buried in the subcutaneous tissue on both sides of the electrode array 101, and the electrode implant is fixed with a dedicated mouse backpack after suturing. The connector is placed outside the skin and connected to the decoder when needed. Since the connector connects the common electrode 102 and the electrode array 101, current or signals can be transmitted.

[0038] Example 3 Since the auditory bulla of mice is small, the contact area of ​​the electrode array 101 after implantation in mice is small, and there is a possibility of dislocation. In addition, since mice are more active, they need to maintain a long-term implantation state when awake, so the electrode array 101 needs to be reasonably fixed.

[0039] Therefore, Figure 5 As shown, on the basis of Example 1, a latex fixing strip 14 with a length of 0.3 mm is symmetrically provided on the first electrode wire 301 at a distance of 2 cm from the electrode array 101, so that after the electrode array 101 is wrapped around the auditory bubble, the latex fixing strip is stretched out at the exit, which can effectively prevent the electrode array 101 from falling out when the mouse is active.

[0040] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A cochlear implant electrode, characterized in that: include: A stimulation electrode section (2) and a connector connected to the stimulation electrode section (2); the stimulation electrode section (2) comprises a first electrode wire (301) and a plurality of second electrode wires (302) connected to the connector, an electrode array (101) arranged at the end of the first electrode wire (301), and a common electrode (102) arranged at the end of the second electrode wire (302); the first electrode wire (301) and the second electrode wire (302) are each wrapped with an insulating tape (7) to expose the electrode array (101) and the common electrode (102); the electrode array (101) comprises a plurality of semi-ring electrodes (5) arranged side by side at the end of the first electrode wire (301); and a flexible insulating suture (6) is provided on one side of the end of the first electrode wire (301) to cross the semi-ring electrode (5).

2. The cochlear implant electrode according to claim 1, characterized in that: The diameter of the flexible insulating suture (6) is 0.05 mm.

3. The cochlear implant electrode according to claim 1, characterized in that: There are three semi-ring electrodes (5) with a diameter of 0.25 mm, a spacing of 0.5 mm, and a width of 0.3 mm. The maximum distance from the semi-ring electrode (5) to the end of the first electrode wire (301) is 2.1 mm.

4. The cochlear implant electrode according to claim 1, characterized in that: An insulating tape (7) is gradually wound around the first electrode wire (301) at a position 1 cm behind the electrode array (101), such that the diameter of the wound first electrode wire (301) is 0.4-0.5 mm, and the winding length of the insulating tape (7) is 3-4 cm.

5. The cochlear implant electrode according to claim 1, characterized in that: The length of the stimulation electrode part (2) is 5 to 6 cm.

6. The cochlear implant electrode according to claim 1, characterized in that: The first electrode wire (301) and a plurality of second electrode wires (302) are connected to the connector via a flexible flat cable (4), and the length of the flexible flat cable (4) is 10 cm.

7. The cochlear implant electrode according to claim 1, characterized in that: The mass of the cochlear implant electrode is 0.5-0.6 g.

8. The cochlear implant electrode according to claim 1, characterized in that: Two second electrode wires (302) are provided, and two common electrodes (102) are provided.

9. The cochlear implant electrode according to claim 1, characterized in that: A latex fixing strip (14) with a length of 0.3 mm is symmetrically provided on the first electrode wire (301) at a distance of 2 cm from the electrode array (101).

10. A use of the cochlear implant electrode according to any one of claims 1 to 9, characterized in that: The cochlear implant electrode is used to be implanted into the cochlea of ​​a small rodent experimental animal, and the auditory nerve response is measured and electrical stimulation is performed when the small rodent experimental animal is awake and moves freely.

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