Cochlear implant and its application

Abstract

The present invention relates to a cochlear electrode implant and its application, belonging to the technical field of surgical medical equipment, comprising: a stimulation electrode part, a connector connected to the stimulation electrode part, the stimulation electrode part comprising 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 comprises a plurality of semi-ring electrodes arranged side by side at the end of the first electrode wire, and a flexible insulating suture crossing the semi-ring electrode is provided on one side of the end of the first electrode wire. The cochlear electrode implant of the present invention can be more easily and stably implanted in the cochlea of ​​a small rodent experimental animal, and can measure the auditory nerve response and perform electrical stimulation when the small rodent experimental animal is awake and free to move.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical medical devices, and particularly to a cochlear implant electrode implant and its application. Background Art

[0002] A cochlear implant converts sound into electrical signals and directly electrically stimulates the peripheral auditory nerve to reconstruct the auditory function. With the gradual improvement of cochlear implant technology, the clinical indications for cochlear implant implantation have gradually widened, and more hearing-impaired people have begun to benefit from this technology.

[0003] Although cochlear implant technology has enabled many people to regain a part of their hearing, there are still significant differences between artificial hearing and natural hearing. In addition, the diversity of hearing impairments has also led to differences in the cochlear implant effects of 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 the hearing impairment conditions of different populations. Therefore, there is a need for cochlear implant electrodes suitable for small rodents such as mice to combine with gene-edited mice to further explore the effects and roles of peripheral electrical stimulation on different disease states of the periphery and the central nervous system, in order to explore more suitable electrical stimulation patterns for each patient.

[0004] Conventional cochlear implant electrodes for animals are relatively large in volume and weight. Although they can be applied to guinea pigs and rats with relatively large cochleas and round windows, the inner ear structures of small rodents such as mice are smaller and more delicate, and the size requirements and surgical requirements for the implant are relatively high. A specially designed implant for mice will reduce the difficulty of animal surgery and the sustainability of the implant to achieve 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 structures of small rodents such as mice, and thus provide a cochlear implant electrode implant and its application.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] One technical solution of the present invention is to provide a cochlear implant electrode implant, including: a stimulating electrode part, and a connector connected to the stimulating electrode part.

[0008] The stimulating electrode part includes a first electrode wire and a plurality of second electrode wires connected to the connector, an electrode array provided at the end of the first electrode wire, and a common electrode provided at the end of the second electrode wire. Insulating tapes are wound around the first electrode wire and the second electrode wires respectively, and the electrode array and the common electrode are exposed. The electrode array includes a plurality of semi-circular electrodes arranged side by side at the end of the first electrode wire. A flexible insulating suture is provided on one side of the end of the first electrode wire and crosses the semi-circular electrodes.

[0009] In some specific embodiments, the diameter of the flexible insulating suture is 0.05 mm.

[0010] In some specific embodiments, there are 3 semi-circular electrodes, with a diameter of 0.25 mm, a spacing of 0.5 mm, a width of 0.3 mm, and the maximum distance from the semi-circular electrodes to the end of the first electrode wire is 2.1 mm.

[0011] In some specific embodiments, insulating tape is gradually wound around the first electrode wire 1 cm behind the electrode array, so that the diameter of the wound first electrode wire is 0.4 - 0.5 mm, and the winding length of the insulating tape is 3 - 4 cm.

[0012] In some specific embodiments, the length of the stimulating electrode part is 5 - 6 cm.

[0013] In some specific embodiments, the first electrode wire and a plurality of second electrode wires are connected to the connector through a flexible flat cable, and the length of the flexible flat cable is 10 cm.

[0014] In some specific embodiments, the mass of the cochlear electrode implant is 0.5 - 0.6 g.

[0015] In some specific embodiments, there are two second electrode wires and two common electrodes.

[0016] In some specific embodiments, latex fixing strips with a length of 0.3 mm are symmetrically provided on the first electrode wire 2 cm away from the electrode array.

[0017] The second technical solution of the present invention is to provide an application of the cochlear electrode implant as described in one of the above technical solutions. The cochlear electrode implant is used to implant into the cochlea of small rodent experimental animals, and measure the auditory nerve response and perform electrical stimulation on small rodent experimental animals in a conscious and freely moving state.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) Due to the significant difference in the cochlear anatomical structure between mice and the traditional guinea pig implantation model, and the presence of the stapedial artery running beneath the round window, the implantation difficulty and material requirements are very high. The cochlear electrode implant of the present invention has the characteristics of smaller volume and mass, enabling it to be more easily and stably implanted into the mouse cochlea. In the mouse cochlear implantation path, the present invention adopts the approach along the posterior edge of the sternocleidomastoid muscle, only opening a small part above the round window of the auditory bulla, bypassing all major arteries and important structures, and can retain the mouse's hearing to the greatest extent. The electrode used in the present invention causes minimal damage to the stapedial artery running beneath the round window, greatly reducing the probability of artery damage during the implantation process and electrical stimulation process, and improving the survival rate of mice.

[0020] (2) The cochlear electrode implant of the present invention reduces the diameter of the stimulating electrode part, increases its durability and toughness. The present invention replaces the traditional circular electrode with a semi-circular electrode, which not only reduces the diameter but also increases the durability, enhancing the adhesion between the electrode and the flexible insulating suture, and reducing the possibility of electrode damage and detachment during and after the operation. Since the biggest problem in 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 implantation. The present invention can greatly improve the success rate of the implant by using a flexible insulating suture in combination with a semi-circular electrode, almost reaching the success rate and postoperative survival rate of traditional guinea pig cochlear implantation.

[0021] (3) The cochlear electrode implant of the present invention can be connected to the stimulation decoder outside the animal through a connector to measure the auditory nerve response and perform electrical stimulation when the mouse is awake and freely moving.

[0022] (4) The miniaturization of the cochlear electrode implant of the present invention is a great progress, making it possible to implant cochlear implants in mice and enabling combined use with other scientific research. Therefore, the cochlear electrode implant provided by the present invention can be widely applied to a variety of gene-edited mice for studying cochlear implantation and its effects in different disease scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of the present invention.

[0024] Figure 2 It is a schematic structural diagram of the first electrode wire and the electrode array of the present invention.

[0025] Figure 3 It is a schematic structural diagram of the electrode array of the present invention.

[0026] Figure 4 It is a schematic diagram of the mouse implantation surgical position and anatomical structure.

[0027] Figure 5Another partial structural schematic diagram of the present invention.

[0028] The markings in the figure are as follows:

[0029] 101 is an electrode array, 102 is a common electrode, 2 is a stimulation electrode part, 301 is a first electrode wire, 302 is a second electrode wire, 4 is a flexible flat cable, 5 is a half-ring electrode, 6 is a flexible insulating suture, 7 is an insulating tape, 8 is the position of the surgical incision, 9 is the mastoid, 10 is the facial nerve, 11 is the stapedial artery, 12 is the round window, 13 is the auditory bulla, and 14 is a latex fixing strip. Specific embodiments

[0030] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0031] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0032] The following will describe in detail some embodiments of the present invention with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0033] In the following embodiments, if there is no specifically described functional component or structure, it means that they are all conventional components or conventional structures adopted in the art to achieve the corresponding functions.

[0034] Embodiment 1

[0035] As Figures 1 to 3 shown, it is a cochlear implant electrode implant, including: a stimulation electrode part 2 and a connector connected to the stimulation electrode part 2. Among them, the stimulation electrode part 2 includes 1 first electrode wire 301 and 2 second electrode wires 302 connected to the connector through a flexible flat cable 4, an electrode array 101 provided at the end of the first electrode wire 301, and a common electrode 102 provided at the end of the second electrode wire 302. The first electrode wire 301 and the second electrode wire 302 are each wound with an insulating tape 7 and the electrode array 101 and the common electrode 102 are exposed. The electrode array 101 includes 3 half-ring electrodes arranged side by side at the end of the first electrode wire 301. The insulating tape 7 can be a silicone tape, and the silicone material has less rejection reaction when implanted into an animal body.

[0036] 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 when implanted in animals.

[0037] 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 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.

[0038] 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.

[0039] The length of the stimulation electrode 2 is 5~6 cm.

[0040] One first electrode wire 301 and two second electrode wires 302 are connected to a connector through a flexible flat cable 4. The length of the flexible flat cable 4 is 10 cm, and a silicone tape is wound around the periphery of the connection. The silicone material rarely causes rejection reactions when implanted into animals. Both the flexible flat cable 4 and the connector are commercially available. Preferably, the flexible flat cable 4 has a specification of 0.5×6P×100 MM. The connector can be flexibly adjusted according to the activity range of the mouse and the size of the special mouse cage. The main purpose of using the connector is to separate it from the decoder and then connect an external decoder when needed. On the one hand, it enables the decoder to be reused, reducing costs. On the other hand, it reduces the weight and volume borne by the animal, helping to reduce trauma and infection and facilitating the animal's self-activity. At the same time, using the flexible flat cable 4 and the connector can make the joint quality smaller than before, which is more suitable for mice with more flexible activities and can reduce the damage probability of the electrodes due to the frequent activities of the experimental animals. The mass of the cochlear implant electrode implant in this embodiment is 0.5 - 0.6 g.

[0041] Example 2

[0042] Based on the cochlear implant electrode implant of Example 1, this example provides the application of the cochlear implant electrode implant, and implants the cochlear implant electrode implant into the cochlea of small rodent experimental animals.

[0043] The following implantation method can be referred to, including the following steps:

[0044] After shaving the skin of a mouse weighing 20 - 30 g, make an incision about 1×1 cm behind the ear, as Figure 4 shown in the surgical incision position 8. Use the posterior auricular nerve as a marker to locate the sternocleidomastoid muscle. Separate the muscle fascia tissue along the posterior edge of the sternocleidomastoid muscle to expose the auditory bulla. Use the mastoid 9, facial nerve 10, and posterior belly of the digastric muscle as markers to open the auditory bulla and expose the round window. Use a 0.3 mm drill bit to open the auditory bulla in the anterosuperior direction, taking care not to damage the stapedial artery 11 below the round window. Taking the stapedial artery 11 as a marker, expand the opening area of the auditory bulla upward to fully expose the round window 12. After piercing the round window membrane with a 0.1 mm platinum wire, push the electrode array 101 into the cochlea along the direction of the scala vestibuli. Use the mouse muscle or fascia tissue to fill the round window to prevent the continuous outflow of lymphatic fluid. Wind the remaining electrode wires into the auditory bulla and fix them, then seal the notch of the auditory bulla with dental bone cement. Then bury the common electrode 102 into the subcutaneous tissue on both sides of the electrode array 101. After suture fixation, fix the electrode implant with a special mouse backpack. 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, it can transmit current or signals.

[0045] Example 3

[0046] 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 properly fixed.

[0047] So if Figure 5 As shown in the figure, based on Example 1, a latex fixing strip 14 with a length of 0.3 mm is symmetrically arranged 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 in 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.

[0048] The above description of the embodiments is to facilitate the understanding and use of the invention by ordinary technicians in the technical field. It is obvious that those familiar with the technical field can easily make various modifications to these embodiments and apply the general principles described here to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments. 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), a connector connected to the stimulation electrode section (2), the stimulation electrode section (2) comprising 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) comprising a plurality of semi-ring electrodes (5) arranged side by side at the end of the first electrode wire (301), a flexible insulating suture (6) crossing the semi-ring electrode (5) is provided on one side of the end of the first electrode wire (301), the diameter of the flexible insulating suture (6) is 0.05 mm, and the semi-ring electrodes (5) are provided with three electrodes, each with a diameter of 0.25 mm, a spacing of 0.5 mm, and a width of 0.3 mm. mm, and the farthest distance from the semi-ring electrode (5) to the end of the first electrode wire (301) is 2.1 mm; when in use, the cochlear electrode implant is implanted into the cochlea of ​​a small rodent experimental animal.

2. 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.

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

4. 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.

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

6. 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.

7. 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).

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