Implantable nerve stimulation electrode and preparation method thereof
By introducing an extended section of a spiral structure and a barrel-shaped stimulation end into the implanted neurostimulation electrode, the problem of insufficient electrode extensibility is solved, and the stability of the electrode and the continuity of the therapeutic effect are achieved during human activities.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-03-13
Smart Images
Figure CN121648459A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of implantable medical devices, and more specifically, to an implantable neurostimulation electrode and a method for preparing the implantable neurostimulation electrode. Background Technology
[0002] With the continuous development of neurostimulation technology, electrical stimulation has been proven to have significant therapeutic effects on a variety of diseases and symptoms, such as deep brain stimulation (DBS) for Parkinson's disease and essential tremor, vagus nerve stimulation (VNS) for epilepsy, sacral nerve modulation (SNM) for urinary dysfunction, and hypoglossal nerve stimulation for obstructive sleep apnea.
[0003] Electrodes, as key components of a neurostimulation system, are responsible for connecting pulse generators or extension leads and transmitting electrical stimulation signals to the target nerve or tissue. In some applications, the nerve structures to be stimulated by the electrodes are columnar, such as the vagus nerve and hypoglossal nerve located in the mandible and / or neck.
[0004] However, existing electrodes lack sufficient flexibility, making it difficult for them to adapt to tissue traction caused by daily activities or changes in body position after implantation. This not only easily causes discomfort to the user but also easily leads to electrode displacement, breakage, or poor contact with the target nerve, thereby affecting the stability of the stimulation effect and the overall therapeutic effect. Summary of the Invention
[0005] The purpose of this invention is to provide an implantable neurostimulation electrode and its preparation method, aiming to solve the defect of insufficient electrode extensibility in related technologies.
[0006] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.
[0007] According to a first aspect of the present invention, an implantable neurostimulation electrode is provided. The electrode is configured to transmit stimulation signals to a columnar nerve located in the mandible and / or neck of a human body; the electrode includes: a stimulation end, an extension end, and a connecting end; The connection end is located near the electrode and is used to connect to a pulse generator; The extension section is connected between the stimulation end and the connection end. The extension section includes a protective sleeve and a wire. The wire is configured to transmit the stimulation signal. The wire passes through the protective sleeve and is at least partially spiral in structure. The ratio of the outer diameter of the spiral structure to the diameter of the wire is set in the range of 3-10 when no external force is applied. The spiral structure has at least a partial deformation recovery capability. When subjected to tension, it can extend along the length direction of the protective sleeve and retract along the length direction of the protective sleeve after the tension is removed. The stimulation end is located at the distal end of the electrode and is configured to wrap around and fix the periphery of the columnar nerve so as to output the stimulation signal to the columnar nerve.
[0008] In an exemplary embodiment of the present invention, the axial length of the spiral structure is not less than 1 / 6 of the total length of the extended section.
[0009] In an exemplary embodiment of the present invention, the stimulation end includes a base, a coiled arm, and stimulation contacts disposed on the inner wall of the coiled arm and the base; the coiled arm extends outward from the end of the base, and when not subjected to external force, the coiled arm is in a coiled state and together with the base forms a barrel-shaped structure.
[0010] In one exemplary embodiment of the present invention, the diameter of the conductor is set in the range of 0.05-0.3 mm.
[0011] In an exemplary embodiment of the present invention, the wire is a composite structure, including a first conductive portion and a second conductive portion; The first conductive part is made of platinum-iridium alloy, nickel-cobalt-chromium-molybdenum alloy or stainless steel, and the second conductive part is made of silver, platinum or platinum-iridium alloy.
[0012] In one exemplary embodiment of the present invention, the first conductive portion covers the second conductive portion along the length direction of the wire; or... The second conductive part covers the first conductive part along the length of the wire.
[0013] In an exemplary embodiment of the present invention, the surface of the conductor is provided with an insulating coating, the thickness of which is set in the range of 0.01-0.05 mm.
[0014] In an exemplary embodiment of the present invention, the extension section is provided with a redundant buffer structure, which is configured to extend when subjected to tensile force.
[0015] According to a second aspect of the present invention, a method for preparing an implantable neurostimulation electrode is provided, comprising the following steps: The conductor is made into a spiral structure and inserted into a protective sleeve to form an extension section; The stimulation end is placed at the distal end of the extension section, and the stimulation contact in the stimulation end is electrically connected and fixed to the wire. Then the stimulation end is injection molded or molded. The connecting end is placed at the near end of the extension section, and the connecting contact point in the connecting end is electrically connected and fixed to the wire. Then the connecting end is injection molded or molded.
[0016] In one exemplary embodiment of the present invention, during the process of forming the wire into a spiral structure and inserting it into the protective sleeve: First, the wire is spirally wound around a core rod along the axial direction. Then, the wire and the core rod are inserted together into the protective sleeve. Finally, the core rod is removed from the protective sleeve.
[0017] Exemplary embodiments of the present invention may have some or all of the following beneficial effects: In an implantable neurostimulation electrode provided in an exemplary embodiment of the present invention, by setting the ratio of the outer diameter of the helical structure to the diameter of the lead wire in the extension section to 3-10, the lead wire can have a larger pitch within the protective sheath, thereby exhibiting good deformability. On one hand, the electrode can deform synchronously with the tissue during daily human activities. When human activity exerts a pulling force on the electrode, the helical structure can extend along the length of the protective sheath, and after the pulling force is removed, the helical structure can retract, thus reducing the pulling sensation on the human body. On the other hand, the protective sheath not only protects the lead wire but also guides its movement, giving the electrode good ductility and fracture resistance during use, effectively reducing the risk of electrode breakage or displacement, and ensuring the structural integrity of the electrode during long-term implantation. In summary, the aforementioned extension section structure gives the electrode good ductility, reducing not only the pulling sensation on the user during use but also the risk of electrode breakage or displacement.
[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description
[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.
[0020] Figure 1A schematic diagram of the structure of an implantable neurostimulation electrode according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of a connection end in an embodiment of the present invention is shown; Figure 3 A schematic diagram of another structure of the connection end in an embodiment of the present invention is shown; Figure 4 A partial schematic diagram of the internal structure of the extension section in an embodiment of the present invention is shown; Figure 5 This diagram illustrates the structure of the stimulation end in a curled state in an embodiment of the present invention. Figure 6 This diagram illustrates the structure of the stimulation end in the unfolded state in an embodiment of the present invention. Figure 7 A cross-sectional view of the conductor cross-section is shown in an embodiment of the present invention.
[0021] Explanation of reference numerals in the attached figures: 1. Stimulating end; 11. Stimulating contact point; 12. Barrel-shaped structure; 13. Substrate; 14. First coil arm; 141. First connecting wire; 15. Second coil arm; 151. Second connecting wire; 2. Extension section; 21. Protective sleeve; 22. Wire; 221. First conductive part; 222. Second conductive part; 223. Insulating coating; 3. Connecting end; 31. Connecting contact point; 32. Base; 4. Fixing anchor; 1. Outer diameter of the spiral structure; 2. Wire diameter. Detailed Implementation
[0022] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and the concept of the exemplary embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted. Furthermore, the drawings are merely illustrative of the invention and are not necessarily drawn to scale.
[0023] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples in the accompanying drawings. It is understood that if the device of the icon is flipped so that it is upside down, the component described as "upper" will become the component described as "lower." When a structure is "upper" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.
[0024] The terms “a,” “one,” “the,” and “at least one” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first” and “second” are used only as markers and are not a limitation on the number of objects. Example 1
[0025] Reference Figure 1 As shown, this embodiment provides an implantable neurostimulation electrode for applying electrical stimulation to columnar nerves (such as the hypoglossal nerve, the main trunk of the vagus nerve, or the accessory nerve) in the mandibular and / or cervical region of a human body. The electrode has a slender and flexible structure, including a stimulation end 1, an extension segment 2, and a connecting end 3 connected in sequence.
[0026] In the embodiments of this application, the end of the electrode that first enters the body during the implantation process and is closest to the target site (such as the columnar nerve) is the distal end, and the end of the electrode that is connected to the external device is the proximal end.
[0027] The connecting end 3 is located at the proximal end of the electrode for connecting to a pulse generator, and has a connecting contact 31 for contacting an external neurostimulator to receive electrical stimulation signals. The stimulation end 1 is located at the distal end of the electrode and has a stimulation contact 11 for releasing electrical stimulation signals to the target site. Depending on the number of connecting contacts 31, the connecting end 3 can adopt different structural forms.
[0028] Reference Figure 2 As shown, when the number of connecting contacts 31 is small (i.e., the number of connecting contacts 31 is one or two), the connecting end 3 can be constructed in the form of a pin contact. That is, the connecting end 3 includes a base 32, in which metal pin contacts are embedded, and some pins are exposed to achieve an interface electrical connection with the pulse generator.
[0029] Reference Figure 3 As shown, when the number of connecting contact points 31 is large (i.e., the number of connecting contact points 31 is three or more), the connecting end 3 can be constructed as a ring-shaped multi-contact structure. Multiple ring-shaped connecting contact points 31 are arranged axially at intervals on the outer periphery of the base 32. Each ring-shaped connecting contact point 31 can independently correspond to one or more stimulation contacts 11 of the stimulation end 1, thereby supporting complex stimulation pattern configurations. Regardless of the form adopted, the surface of the base 32 other than the connecting contact points 31 is covered with a biocompatible insulating material, such as medical silicone or polyurethane, to ensure electrical safety and tissue compatibility in long-term implantation environments.
[0030] The number and arrangement of the stimulation contacts 11 can be customized according to clinical needs. When the stimulation end 1 is in a curled state, the stimulation contacts 11 are a single ring contact or multiple segmented ring contacts set on the inner wall of the stimulation end, or a dotted array distributed along the nerve axis. The stimulation contacts 11 are made of inert conductive materials, such as platinum, platinum-iridium alloy, or titanium nitride. The overall shape of the stimulation end 1 can also be adapted according to the diameter and anatomical morphology of the target nerve, for example, designed as an openable C-shaped clamping structure, a semi-enclosed flexible support, or a fixation platform with suture wings, which facilitates precise intraoperative positioning and firm anchoring to the nerve or specific area, making it less prone to slippage or displacement postoperatively.
[0031] Reference Figure 1 and Figure 4 As shown, extension section 2 connects stimulation end 1 and connection end 3. Extension section 2 includes a protective sleeve 21 and a wire 22, with the wire 22 passing through the protective sleeve 21. The wire 22 is used to transmit the stimulation signal from connection end 3 to stimulation end 1.
[0032] Crucially, the lead wire 22 has at least a portion of a spiral structure inside the protective sleeve 21. This spiral structure extends axially along the protective sleeve 21 and possesses at least partial deformability to recover its deformation. When the electrode is subjected to axial tension during or after implantation due to head rotation, swallowing, or neck movement by the patient, this spiral structure can moderately extend along the length of the protective sleeve 21, effectively absorbing the traction force. After the external force is removed, relying on the material's own deformation capacity, at least a portion can recover its deformation, thus preventing the lead wire 22 from breaking or shifting. Therefore, this structure effectively improves the electrode's durability and long-term stability in dynamic physiological environments.
[0033] Preferably, the spiral structure can completely retract to its initial state after the external force is removed.
[0034] Furthermore, the axial length of the spiral structure is not less than 1 / 6 of the total length of the extension segment 2. For example, this ratio can be 1 / 6, 1 / 4, 1 / 3, or 1 / 2, etc. Of course, it is understood that in some embodiments, the lead wire 22 can be constructed as a spiral structure throughout the entire length of the extension segment 2, that is, the axial length of the spiral structure is equal to the total length of the extension segment 2. The above design can be flexibly adjusted according to the mobility of the implantation site, the required extension stroke, and the overall flexibility requirements of the electrode, ensuring that the lead wire can be fully stretched when subjected to tension, thereby reducing the user's pulling sensation and improving comfort.
[0035] In a preferred embodiment, the outer diameter of the spiral structure is set to be 1. The diameter of conductor 22 is set as follows: 2. 1 and The ratio of 2 is set in the range of 3-10, for example... 1: The ratio 2 can be 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, or 9:1, etc. A ratio range of not less than 3 ensures sufficient extension stroke to accommodate a wide range of neck movements, while a ratio range of not more than 10 ensures that the spiral structure can retract after being stretched. Meanwhile, the protective sleeve 21 is made of a soft and kink-resistant medical-grade polymer material, such as medical-grade silicone, highly elastic polyurethane, or expanded polytetrafluoroethylene. Its inner diameter is slightly larger than the maximum outer diameter of the spiral structure, providing ample space for the movement of the lead 22.
[0036] In practical applications, the implantable neurostimulation electrode of this invention can be implanted below the angle of the mandible or near the carotid sheath via minimally invasive surgery. The stimulation end 1 encircles the target nerve, the extension segment 2 extends along a subcutaneous tunnel to the subclavian region (chest), and the connecting end 3 connects to the implantable pulse generator. Thanks to the helical structure of the lead wire 22, it achieves elastic buffering characteristics, ensuring stable electrical performance and mechanical integrity even when the patient frequently turns their head or performs large-amplitude neck movements. This not only improves user comfort but also reduces the likelihood of electrode displacement, breakage, or poor contact with the target nerve, thereby enhancing the stability of the electrode stimulation effect and the overall therapeutic effect.
[0037] Reference Figure 5 and Figure 6 As shown, the stimulation end 1 is further constructed as a barrel-shaped structure 12, which surrounds and wraps around the periphery of the columnar target nerve, and the stimulation contact 11 is disposed on the inner wall of the barrel-shaped structure 12. The stimulation end 1 using the barrel-shaped structure 12 has the following advantages: Firstly, the target nerve passes through the center of the barrel-shaped structure 12, allowing the stimulation contact points 11 to be distributed circumferentially along the target nerve and to form a large-area adhesion with the target nerve epineurium, increasing the coverage area of the target nerve stimulation, thereby improving the uniformity and reliability of the electrical stimulation and ensuring the long-term stability of the stimulation effect.
[0038] Secondly, the barrel-shaped structure 12 forms a circumferential wrap around the nerves, which enhances the coupling between the stimulation end 1 and the target nerve, making it less likely for the electrode to slip axially or rotate due to neck movement or tissue peristalsis after surgery, thus significantly improving the stability of the fixation.
[0039] Thirdly, the barrel structure 12 is made of flexible biocompatible material, which has good radial compliance and can deform synchronously with the target nerve. It is not easy to restrict the bending of the target nerve, thereby reducing the shear stress and compression damage to the nerve.
[0040] In this embodiment of the invention, the stimulation end 1 includes a base 13, a first coiled arm 14, and a second coiled arm 15. The first coiled arm 14 and the second coiled arm 15 extend outwards from opposite ends of the base 13, forming a single, integral structure made of a flexible material with excellent elasticity and biocompatibility, such as medical silicone, polyurethane rubber, or other elastic polymer materials suitable for long-term implantation. When connecting the stimulation end 1 to the target columnar nerve, the user can pull the first coiled arm 14 and the second coiled arm 15 outwards, allowing the target columnar nerve to adhere to the inner side of the base 13. Then, the user releases the first coiled arm 14 and the second coiled arm 15. The first coiled arm 14 and the second coiled arm 15 will automatically coil and enclose the target columnar nerve.
[0041] To further facilitate user operation, the first coil arm 14 is connected to a first connecting line 141 at its end away from the base 13, and the second coil arm 15 is connected to a second connecting line 151 at its end away from the base 13. The first connecting line 141 and the second connecting line 151 are made of non-absorbable sutures, such as polyester fiber, expanded polytetrafluoroethylene sutures, or other high-strength medical sutures, and are used to apply controllable tension during implantation.
[0042] During surgical implantation, medical staff pull on the first connecting line 141 and the second connecting line 151, causing the first coil arm 14 and the second coil arm 15 to overcome their own elastic force and unfold radially along the outside of the base 13, thereby expanding the size of the opening formed by the base 13 and the two coil arms. Then, the target columnar nerve is placed into the central area of the opening, and the base 13 is initially attached to the nerve surface. When the tension on the first connecting line 141 and the second connecting line 151 is released, the first coil arm 14 and the second coil arm 15 automatically retract and curl under the action of the material's elastic restoring force, finally forming a complete barrel-shaped structure 12, which stably wraps the target nerve in the barrel-shaped structure 12 formed by its inner cavity.
[0043] Reference Figure 7 As shown, in this embodiment of the invention, the diameter of the lead wire 22 is set in the range of 0.05-0.3 mm, for example, it can be 0.05 mm, 0.08 mm, 0.1 mm, 0.13 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.25 mm, or 0.3 mm. Setting the diameter of the lead wire 22 within this range helps to reduce the overall cross-sectional area, improve flexibility and minimally invasive implantation, and is especially suitable for areas with limited anatomical space and frequent movement, such as the neck.
[0044] In this embodiment of the invention, the conductor 22 is a composite structure made of high-strength and low-resistivity materials. The conductor 22 includes a first conductive portion 221 and a second conductive portion 222. The first conductive portion 221 covers the second conductive portion 222 along the length of the conductor 22, and the second conductive portion 222 is disposed inside the first conductive portion 221 as the core of the conductor 22. The first conductive portion 221 and the second conductive portion 222 together serve as the load-bearing and conductive core of the conductor 22. The first conductive portion 221 is made of materials such as platinum-iridium alloy, nickel-cobalt-chromium-molybdenum alloy, or stainless steel, while the second conductive portion 222 is made of materials such as silver, platinum, or platinum-iridium alloy. One of the two conductive portions ensures the high strength of the conductor 22, and the other ensures the low resistivity of the conductor 22, achieving efficient and stable transmission of the stimulation signal. It should be noted that the above materials are only illustrative and not limiting. In some other embodiments, the second conductive portion 222 may also cover the first conductive portion 221 along the length of the conductor 22, with the first conductive portion 221 serving as the core of the conductor 22.
[0045] In this embodiment of the invention, the surface of the wire 22 is coated with an insulating coating 223. The thickness of the insulating coating 223 is set in the range of 0.01-0.05mm, for example, it can be 0.01mm, 0.02mm, 0.03mm, 0.04mm or 0.05mm. This thin layer design ensures reliable insulation performance while effectively controlling the overall outer diameter of the wire 22, which is beneficial to improving the flexibility and minimally invasive implantation of the electrode.
[0046] For example, the insulating coating 223 may be made of fluoroplastics (such as polytetrafluoroethylene PTFE, FEP or PFA), polyimide (PI), parylene polymer (Parylene C) or other medical polymer insulating materials suitable for long-term implantation.
[0047] In this embodiment of the invention, the extension section 2 (i.e., the overall structure of the protective sleeve 21 and the lead wire 22) is provided with a redundant buffer structure. The buffer structure is configured to extend along the length of the electrode when subjected to axial tensile force. The buffer structure may be partially or entirely in the form of a spiral, corrugated, or S-shaped shape, etc. Its core function is to absorb the tensile force generated by neck movement, swallowing, or head rotation, thereby providing a buffering effect and reducing the external force transmitted to the stimulation end 1 or the connection end 3, thus protecting the extension section 2 and making it less prone to breakage, electrode displacement, or nerve traction damage.
[0048] By setting up this buffer structure, the extension segment 2 effectively improves the durability and long-term stability of the electrode in dynamic physiological environments while maintaining the overall small diameter and flexibility. It is especially suitable for nerve stimulation that needs to be implanted in highly mobile anatomical areas (such as the mandible and neck) for a long time.
[0049] Furthermore, the buffer structure is preferably designed to automatically retract to its original state after the tension is removed.
[0050] In an embodiment of the present invention, an implantable neurostimulation electrode further includes a fixing anchor 4, which is sleeved on the extension section 2. The fixing anchor 4 can be fixedly connected to the extension section 2 or slidably connected to the extension section 2. The fixing anchor 4 can be provided with multiple annular fixing grooves, and the fixing grooves can be set to two or three. The fixing grooves are used to place medical binding wires, so as to facilitate the fixing anchor 4 to human tissue by binding wires.
[0051] Example 2 In this embodiment of the invention, a method for preparing an implantable neurostimulation electrode is also disclosed, which is applicable to the preparation of any one of the implantable neurostimulation electrodes in Example 1.
[0052] The preparation method includes the following steps: The conductor 22 is made into a spiral structure and inserted into the protective sleeve 21 to form the extension section 2; A fixed anchor 4 is installed on the extension section 2. The fixed anchor 4 can move along the extension section 2 or be fixed to the extension section 2, and there is no restriction on this. The stimulation end 1 is placed at the far end of the extension section 2. The stimulation contact 11 is electrically connected and fixed to the wire 22 by means of laser welding, resistance welding, mechanical connection, etc. Then, the stimulation end 1 is formed by injection molding or compression molding using tooling molds, etc. The connecting end 3 is placed near the end of the extension section 2. The connecting contact point 31 is electrically connected and fixed to the wire 22 by means of laser welding, resistance welding, mechanical connection, etc. Then, the connecting end 3 is formed by injection molding or compression molding using tooling molds and other methods.
[0053] The following steps can be taken in the specific operation of making the conductor 22 into a spiral structure and inserting it into the protective sleeve 21: First, tightly spiral the wire 22 onto a core rod to form a spiral structure with a preset pitch and outer diameter; Then, insert the core rod with the wire 22 wrapped around it into the inner cavity of the protective sleeve 21; After the conductor 22 and the core rod have fully entered the protective sleeve 21, the core rod is slowly pulled out, leaving the spiral conductor 22 inside the protective sleeve 21, thus forming an extension section 2 structure with elastic expansion and contraction capabilities.
[0054] This manufacturing process has advantages such as controllable operation, good structural consistency, and high yield. With the aid of mandrel forming, the helical parameters (such as pitch, outer diameter, or number of turns) can be precisely controlled to ensure stable extension and retraction performance in subsequent use; at the same time, it avoids deformation or damage to the wire 22 caused by direct insertion without support, and is especially suitable for assembling ultrafine wires 22 with a diameter of less than 0.1 mm.
[0055] It should be noted that the core rod can be made of stainless steel, polytetrafluoroethylene (PTFE) or other medical-grade materials with smooth surfaces and moderate rigidity. Its outer diameter is slightly smaller than the inner diameter of the protective sleeve 21 to ensure smooth insertion and withdrawal.
[0056] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments thereof. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not claimed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the appended claims.
Claims
1. An implantable neurostimulation electrode, characterized in that, The electrode is configured to transmit stimulation signals to a columnar nerve located in the mandible and / or neck of a human body; the electrode includes: a stimulation end, an extension end, and a connecting end; The connection end is located near the electrode and is used to connect to a pulse generator; The extension section is connected between the stimulation end and the connection end. The extension section includes a protective sleeve and a wire. The wire is configured to transmit the stimulation signal. The wire passes through the protective sleeve and is at least partially spiral in structure. The ratio of the outer diameter of the spiral structure to the diameter of the wire is set in the range of 3-10 when no external force is applied. The spiral structure has at least a partial deformation recovery capability. When subjected to tension, it can extend along the length direction of the protective sleeve and retract along the length direction of the protective sleeve after the tension is removed. The stimulation end is located at the distal end of the electrode and is configured to wrap around and fix the periphery of the columnar nerve so as to output the stimulation signal to the columnar nerve.
2. The implantable neurostimulation electrode according to claim 1, characterized in that, The axial length of the spiral structure is not less than 1 / 6 of the total length of the extended section.
3. An implantable neurostimulation electrode according to claim 1, characterized in that, The stimulation end includes a base, a coiled arm, and stimulation contacts disposed on the inner wall of the coiled arm and the base; the coiled arm extends outward from the end of the base, and when not subjected to external force, the coiled arm is in a coiled state and together with the base forms a barrel-shaped structure.
4. An implantable neurostimulation electrode according to claim 1, characterized in that, The diameter of the conductor is set in the range of 0.05-0.3 mm.
5. An implantable neurostimulation electrode according to claim 1, characterized in that, The wire has a composite structure, including a first conductive part and a second conductive part; The first conductive part is made of platinum-iridium alloy, nickel-cobalt-chromium-molybdenum alloy or stainless steel, and the second conductive part is made of silver, platinum or platinum-iridium alloy.
6. An implantable neurostimulation electrode according to claim 5, characterized in that, The first conductive portion covers the second conductive portion along the length of the wire; or... The second conductive part covers the first conductive part along the length of the wire.
7. An implantable neurostimulation electrode according to claim 1, characterized in that, The surface of the conductor is provided with an insulating coating, the thickness of which is set in the range of 0.01-0.05 mm.
8. An implantable neurostimulation electrode according to claim 1, characterized in that, The extension section is provided with a redundant buffer structure, which is configured to extend when subjected to tensile force.
9. A method for preparing an implantable neurostimulation electrode, characterized in that, Includes the following steps: The conductor is made into a spiral structure and inserted into a protective sleeve to form an extension section; The stimulation end is placed at the distal end of the extension section, and the stimulation contact in the stimulation end is electrically connected and fixed to the wire. Then the stimulation end is injection molded or molded. The connecting end is placed at the near end of the extension section, and the connecting contact point in the connecting end is electrically connected and fixed to the wire. Then the connecting end is injection molded or molded.
10. A method for preparing an implantable neurostimulation electrode according to claim 9, characterized in that, The process involves forming the wire into a spiral structure and inserting it into the protective sleeve: First, the wire is spirally wound around a core rod along the axial direction. Then, the wire and the core rod are inserted together into the protective sleeve. Finally, the core rod is removed from the protective sleeve.