Controllably segmented de-coil spring system

Abstract

The present application relates to the field of medical devices, and discloses a controllable segmented release spring coil system, which comprises an implanted spring, an anti-release wire, a delivery rod and a delivery microcatheter, the anti-release wire is arranged in the implanted spring, and first exposed points and second exposed points separated by insulation areas are arranged along the length direction of the implanted spring at intervals. The present application sets the first exposed points and the second exposed points separated by insulation areas on the anti-release wire, and makes the delivery rod conductive with the anti-release wire, and the cathode developing member at the distal end of the delivery microcatheter conductive with the conductive support structure. When the target exposed point moves out of the distal end of the delivery microcatheter, the target exposed point can form a local electrolytic loop with the cathode developing member near the distal end of the delivery microcatheter, so that the electrolytic reaction occurs at the target exposed point, and the situation that the release waiting time is long and the target release point reaction is not concentrated due to the long distance of the cathode position is reduced.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more particularly to a controllable segmented release coil system. Background Technology

[0002] Currently, coil embolization is one of the commonly used embolization methods in interventional treatment of intracranial aneurysms and other vascular lesions. It usually involves delivering a microcatheter to insert an embolic coil into the aneurysm cavity, where the coil coils and baskets within the aneurysm cavity to form a thrombus, reducing the risk of aneurysm rupture. In current coil systems, some products use fixed-length coils, requiring the operator to repeatedly select different sizes of coils based on the aneurysm morphology and occlusion status. Other approaches attempt to achieve selectable length release through multiple segmented coils, multiple release points, or mechanical clamping structures to reduce the frequency of coil replacements.

[0003] A search revealed that CN218528814U discloses an embolization spring coil assembly, which includes two or more segmented spring coils. The connection position between two adjacent segmented spring coils has a snap-fit ​​device, which includes a first snap and a second snap. The snap-fit ​​device cooperates with the delivery tube to realize the connection and separation between adjacent segmented spring coils. This solution can use multiple snap-fit ​​devices to form multiple release points, thereby selecting the number and length of spring coils to be inserted into the patient's intracranial aneurysm as needed. However, its separation process mainly depends on the dimensional fit between the snap-fit ​​structure and the delivery tube.

[0004] The aforementioned mechanical snap-fit ​​segmented release structure has high requirements for the dimensional fit between the snap-fit, the conveying pipe, and the segmented spring coils. If the fit is too tight, it may affect the smooth separation after the segmented spring coils are removed from the conveying pipe; if the fit is too loose, it may affect the connection stability during the conveying process.

[0005] For electrolytically released spring coils, existing structures typically achieve spring coil release by electrolytically corroding specific release points. However, the distance between the cathode position and the target release point in the electrolytically released structure is relatively far, and the concentration of the electrolytic reaction near the target release point is insufficient, which can easily lead to a long release waiting time. Summary of the Invention

[0006] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a controllable segmented release spring coil system, which solves the problems of existing segmented release spring coils relying on mechanical snap-fit ​​structures for separation, where the separation reliability is greatly affected by dimensional fit, the electrolytic reaction near the target release point of the electrically released spring coil is not concentrated enough, the release waiting time is long, and non-target release points are prone to accidental corrosion.

[0007] (II) Technical Solution To achieve the above objectives, the present invention is implemented through the following technical solutions.

[0008] A controllable segmented release spring coil system includes an implanted spring, an anti-unwinding wire, a delivery rod, and a delivery microcatheter. The anti-unwinding wire is inserted into the implanted spring and has a first exposed point and a second exposed point separated by an insulating region along the length of the implanted spring. The delivery rod is connected to the anti-unwinding wire and is used to connect to the positive terminal of a power supply. The distal end of the delivery microcatheter has an exposed cathode imaging element, which is connected to a conductive support structure inside the delivery microcatheter and is used to connect to the negative terminal of a power supply. The delivery rod has a marking strip for indicating the position of the exposed point relative to the distal end of the delivery microcatheter. When any exposed point moves out of the distal end of the delivery microcatheter, the exposed point and the cathode imaging element form a local electrolytic circuit, causing the implanted spring to separate at that exposed point.

[0009] In one embodiment, the cathode developing element is a second developing ring, and the delivery microcatheter includes an outer resin layer. The outer resin layer has an annular break at a position corresponding to the second developing ring, and the second developing ring is exposed on the outer surface of the distal end of the delivery microcatheter through the annular break.

[0010] Preferably, the conductive support structure includes a winding wire and a braided tube, the cathode developing element is connected to the winding wire, the winding wire is connected to the braided tube, the braided tube is connected to the cathode needle, and the cathode needle is used to connect to the negative terminal of the power supply.

[0011] In one embodiment, the proximal end of the cathode developing element is welded to the distal end of the winding wire, the proximal end of the winding wire is welded to the braided tube, and the proximal end of the braided tube is welded to the cathode needle.

[0012] In one embodiment, multiple marker strips are of the same length and the interval between two adjacent marker strips is the same. The multiple marker strips are respectively set to correspond to multiple exposed points, which are used to determine whether the target exposed point exposes the distal end of the delivery microcatheter under X-ray.

[0013] In one embodiment, the distance between two adjacent exposed points is not less than 5 mm.

[0014] Preferably, the controllable segmented release spring coil system further includes a power control unit, which is used to provide short-term output to the local electrolysis circuit, and the power control unit is set to output for no more than 2 seconds at a time under 24V voltage conditions.

[0015] In one embodiment, the anti-derotation wire includes a metal core and an insulating layer covering the outside of the metal core, and the first exposure point and the second exposure point are both electrolytic exposure areas formed after the insulating layer is removed.

[0016] In a preferred embodiment, the metal core is a 316LVM stainless steel core, the insulation layer is a PI insulation layer, the first exposed point and the second exposed point are both formed by laser ablation of the PI insulation layer, the length of the first exposed point (5) is 0.015-0.035mm, the length of the second exposed point (12) is 0.03mm-0.07mm, the diameter of the 316LVM stainless steel core is 0.012mm-0.018mm, and the thickness of the PI insulation layer is 3μm-8μm.

[0017] In another preferred embodiment, the conveying rod includes an anode wire and an anode conductive tube, the anode conductive tube being connected to the proximal end of the anode wire, the distal end of the anode wire being connected to an anti-unwinding wire, and the anode conductive tube being used to connect to the positive terminal of the power supply.

[0018] (III) Beneficial Effects This invention provides a controllable segmented release spring coil system. Compared with the prior art, it has the following advantages: By setting a first and second exposed point separated by an insulating area on the anti-unwinding wire, and connecting the delivery rod to the anti-unwinding wire and the cathode developing element at the distal end of the delivery microcatheter to the conductive support structure, when the target exposed point moves out of the distal end of the delivery microcatheter, the target exposed point can form a local electrolytic circuit with the cathode developing element near the distal end of the delivery microcatheter. This concentrates the electrolytic reaction at the target exposed point, reducing the long waiting time for release and the lack of concentrated reaction at the target release point caused by the far-away cathode position.

[0019] By setting markers on the delivery rod to indicate the position of the exposed point relative to the distal end of the delivery microcatheter, and by setting multiple markers corresponding to multiple exposed points, the operator can determine under X-ray whether the first exposed point, the second exposed point, or other target exposed points expose the distal end of the delivery microcatheter, thereby improving the accuracy of the release position determination. At the same time, by ensuring that the distance between two adjacent exposed points is not less than 5mm, and by coordinating with the power control unit to ensure that the single output time does not exceed 2 seconds under 24V voltage conditions, the risk of accidental corrosion or synchronous breakage of non-target exposed points due to prolonged power supply or excessive distance can be reduced.

[0020] By setting the cathode developing element as the second developing ring, and making the second developing ring form a negative electrode conduction path through the winding wire, braided tube and cathode needle, the second developing ring can serve as both a developing positioning structure for the distal end of the delivery microcatheter and a cathode end for the local electrolysis circuit to participate in the release process, thus realizing the reuse of the developing structure and the cathode structure. The first and second exposed points on the anti-unwinding wire are formed by removing the insulation layer, which can limit the electrolytic breakage position while maintaining the insulation isolation of the non-exposed area, and take into account the flexibility of the spring coil, the anti-unwinding ability and the segmented release stability. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the controllable segmented release spring coil system of the present invention.

[0023] Figure 2 This is a partially enlarged structural diagram showing the connection relationship between the implanted spring, anti-unwinding wire, and the distal end of the conveying rod in this invention.

[0024] Figure 3 This is a cross-sectional schematic diagram of the microcatheter for delivery according to the present invention.

[0025] Figure 4 This is a schematic diagram of the overall structure of the delivery microcatheter of the present invention.

[0026] Figure 5 This diagram illustrates the combined use of the microcatheter and spring coil of the present invention.

[0027] Figure 6 This is a schematic diagram of the structure of the spring implanted in this invention when it is in a two-dimensional configuration.

[0028] Figure 7 This is a schematic diagram of the structure of the spring implanted in this invention when it is in a three-dimensional configuration.

[0029] Figure 8 This is a schematic diagram of the structure of the present invention, in which the implanted spring is loaded inside the insertion sheath.

[0030] The attached figures are labeled as follows: 1. Ball cap; 2. Anti-unwinding wire; 3. Implanted spring; 4. Fixing plate; 5. First exposed point; 6. First solder joint; 7. First adhesive point; 8. Second adhesive point; 9. Second solder joint; 10. First developing ring; 11. Anode wire; 12. Second exposed point; 13. Adhesive dot; 14. Support spring; 15. Conveyor steel pipe; 16. Marking tape; 17. Anode conductive tube; 18. Second developing ring; 19. Winding wire; 20. Braided tube; 21. Solder; 22. PTFE inner tube; 23. Outer resin layer; 24. Cathode needle; 25. Tube seat; 26. Introducing sheath. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides a controllable segmented electrolytically release coil system, including an implanted spring 3, an anti-unwinding wire 2, a delivery rod, and a delivery microcatheter. The implanted spring 3 is used to be delivered into the aneurysm cavity via the delivery microcatheter to form an embolized filling structure within the aneurysm cavity. The anti-unwinding wire 2 is inserted into the implanted spring 3 and extends along the length of the implanted spring 3 to reduce the risk of unwinding of the implanted spring 3 during the pushing, retraction, or shaping process.

[0033] The anti-derotation wire 2 is provided with multiple exposed points separated by insulating regions along the length direction of the implanted spring 3. The multiple exposed points include a first exposed point 5 and a second exposed point 12. The first exposed point 5 and the second exposed point 12 are respectively selected electrochemical fracture regions. When either the first exposed point 5 or the second exposed point 12 is used as the target exposed point and moved away from the distal end of the delivery microcatheter, the target exposed point can form a local electrolytic circuit with the cathode imaging element at the distal end of the delivery microcatheter, causing the implanted spring 3 to separate at the target exposed point, thereby releasing the implanted spring 3 of the corresponding length.

[0034] The anti-derotation wire 2 may include a metal core and an insulating layer covering the outside of the metal core. The first exposed point 5 and the second exposed point 12 are electrolytic exposure areas formed after the insulating layer is removed. Specifically, the metal core may be a 316LVM stainless steel core, the insulating layer may be a PI insulating layer, the first exposed point 5 and the second exposed point 12 may be formed by laser ablation of the PI insulating layer, the length of the first exposed point 5 is 0.015-0.035mm, the length of the second exposed point 12 is 0.03mm-0.07mm, the diameter of the 316LVM stainless steel core may be 0.012mm-0.018mm, and the thickness of the PI insulating layer may be 3μm-8μm.

[0035] In a preferred embodiment, the diameter of the metal core is 0.016 mm, the length of the first exposed point 5 is 0.02 mm, the length of the second exposed point 12 is 0.05 mm, and the thickness of the PI insulation layer is 6 μm. The above dimensions can ensure the basic mechanical strength of the anti-unwinding wire 2 while enabling the target exposed point to undergo electrochemical corrosion fracture quickly under energized conditions. The insulation area is used to reduce the possibility of non-target areas participating in electrochemical reactions.

[0036] The distal end of the implanted spring 3 is provided with a ball cap 1, which can be formed by curing with ultraviolet light-curing adhesive and is fixedly connected to the distal end of the anti-unwinding wire 2. The ball cap 1 is used to seal the distal end of the implanted spring 3 and reduce distal end jamming and scraping when the implanted spring 3 enters the inlet sheath 26, delivers the microcatheter or aneurysm cavity, while reducing the risk of the distal end of the implanted spring 3 puncturing the blood vessel wall or aneurysm wall.

[0037] A fixing plate 4 may also be provided inside the implanted spring 3. The fixing plate 4 may be made of platinum alloy, platinum-iridium alloy or other metal with imaging properties and biocompatibility. The fixing plate 4 is fixedly connected to the implanted spring 3 and to the anti-unwinding wire 2. It is used to keep the anti-unwinding wire 2 in the inner area of ​​the implanted spring 3, improve the stability of the pushing force transmission, and reduce the risk of uneven local force on the implanted spring 3 caused by the deviation of the anti-unwinding wire 2.

[0038] Specifically, the implanted spring 3 and the fixing plate 4 can be spot welded together to form a first weld point 6, and the fixing plate 4 and the anti-unwinding wire 2 can be fixed together with thermosetting adhesive to form a first bonding point 7. The first weld point 6 is used to improve the connection reliability between the fixing plate 4 and the implanted spring 3, and the first bonding point 7 is used to fix the position of the anti-unwinding wire 2 without significantly increasing the rigidity of the implanted spring 3.

[0039] The anti-unwinding wire 2 can extend into the implanted spring 3 in a wavy or loosely curved shape, so that while the anti-unwinding wire 2 undertakes the functions of anti-unwinding and conductivity, it will not excessively restrict the bending deformation of the implanted spring 3. When the implanted spring 3 is coiled in the aneurysm cavity, the wavy or loosely curved anti-unwinding wire 2 can adapt to the deformation of the implanted spring 3, thereby maintaining the flexibility and packing adaptability of the implanted spring 3.

[0040] The proximal end of the implanted spring 3 may be provided with a first radiopaque ring 10, which is fixedly connected to the implanted spring 3. Specifically, the implanted spring 3 and the first radiopaque ring 10 can be spot welded together by laser to form a second weld point 9. The first radiopaque ring 10 is used to indicate the proximal position of the implanted spring 3 under X-ray. When the implanted spring 3 undergoes abnormal unwinding or abnormal stretching of the proximal structure, the surgeon can identify it by the positional change between the first radiopaque ring 10 and the implanted spring 3.

[0041] The implanted spring 3, the anti-unwinding wire 2, and the conveying rod can also be further fixed by an adhesive structure. For example, a second bonding point 8 can be formed between the implanted spring 3, the anti-unwinding wire 2, and the anode wire 11 by a thermosetting adhesive. The second bonding point 8 is used to improve the connection stability between the proximal region of the implanted spring 3 and the distal region of the conveying rod, and to reduce shaking or swaying at the connection point during the pushing of the implanted spring 3.

[0042] This embodiment allows the operator to control the output length of the spring coil in real time according to the actual three-dimensional shape of the aneurysm when releasing the first spring coil, so as to achieve a tailored basket formation. When the spring coil forms a stable three-dimensional frame in the aneurysm sac and perfectly covers the aneurysm neck, the operator can immediately release it at the selected length without being bound by the preset length, so that the fit between the basket coil and the aneurysm is optimal.

[0043] The coils feature a continuous delivery and selectable length release design. Throughout the embolization process, it is not necessary to completely remove the push rod from the body to replace coils of different sizes. By continuously delivering the same coil and releasing it in segments as needed, the support force inside the microcatheter can be kept relatively constant. This avoids drastic fluctuations in system tension caused by changing instruments. Especially when dealing with small or fragile aneurysms, this ensures the stability of the microcatheter tip throughout the embolization process and improves the safety of the procedure.

[0044] In the final stage of embolization, for the remaining irregular micro-gaps in the tumor cavity, the surgeon can control the length of the last spring coil. When it is observed that the gap is just filled and there is no excessive pushing, it can be released instantly. This makes the achievement of dense embolization no longer dependent on whether there is a prefabricated spring coil of the right size, but on the surgeon's accurate judgment, which effectively improves the long-term cure rate.

[0045] Example 2 like Figure 1 and Figure 2 As shown, the delivery rod is used to push the implanted spring 3 to move axially within the delivery microcatheter and to form an anode conductive path with the anti-unwinding wire 2. The delivery rod includes an anode wire 11, a support spring 14, a delivery steel pipe 15, a marking strip 16, and an anode conductive tube 17, wherein the anode conductive tube 17 is connected to the proximal end of the anode wire 11, the distal end of the anode wire 11 is connected to the anti-unwinding wire 2, and the anode conductive tube 17 is used to connect to the positive terminal of the power supply.

[0046] The anode wire 11 can be a 316LVM stainless steel wire with a PI coating, and the anode conductive tube 17 can be a stainless steel tube or other conductive metal tube. The anode conductive tube 17 and the near end of the anode wire 11 can be connected by welding, crimping or bonding with conductive adhesive. The insulation layer can be removed from the far end of the anode wire 11 and the connection end of the anti-unwinding wire 2 and they can be hooked together to form a mechanical connection and electrical connection between the anode wire 11 and the anti-unwinding wire 2.

[0047] In the above connection relationship, the positive terminal of the power supply can be conducted to the first exposed point 5 or the second exposed point 12 in sequence through the anode conductive tube 17, the anode wire 11 and the anti-unwinding wire 2, so that the target exposed point selected to be moved out of the distal end of the delivery microcatheter is used as the anode electrolytic fracture area; by setting the anode conduction path in the delivery rod and the anti-unwinding wire 2, it is possible to avoid setting an independent anode wire outside the implanted spring 3, thereby reducing the impact on the flexibility of the implanted spring 3.

[0048] A support spring 14 is disposed at the distal end of the delivery rod to form a flexible distal end of the delivery rod to adapt to the tortuous anatomical structure of intracranial blood vessels. The support spring 14 and the anode wire 11 can be bonded together with thermosetting adhesive to form an adhesive dot 13. The adhesive dot 13 is used to limit the relative movement of the anode wire 11 within the support spring 14 and to improve the overall structural stability of the distal end of the delivery rod.

[0049] The conveying steel pipe 15 is located at the near end of the conveying rod to provide near-end support force and push force transmission capability of the conveying rod; the support spring 14 can be nested in the far end of the conveying steel pipe 15 and fixedly connected by solder 21. Solder 21 is used to form a reliable connection between the support spring 14 and the conveying steel pipe 15, so that the push force of the conveying steel pipe 15 can be smoothly transmitted to the support spring 14 and the implanted spring 3.

[0050] The distal end of the conveying steel pipe 15 may be provided with a grinding section, which forms a tapered gradual transition structure to improve the compliance of the distal end of the conveying rod; the middle section of the conveying steel pipe 15 may be a constant outer diameter section to provide better support force; the proximal end of the conveying steel pipe 15 may be provided with a short taper grinding section, and the anode conductive pipe 17 is sleeved on the outside of the short taper grinding section so that the anode conductive pipe 17 can be easily connected to the positive terminal of the power supply.

[0051] An insulating layer may be provided between the anode conductive tube 17 and the conveying steel pipe 15. This insulating layer may be a polyimide layer, a heat-shrinkable insulating tube, or an insulating coating. This insulating layer is used to reduce unintended conduction between the anode conductive tube 17 and the conveying steel pipe 15, and to prevent the current from forming a bypass through the conveying steel pipe 15, thereby improving the concentration of the electrolytic reaction at the target exposed point.

[0052] The conveying rod is provided with multiple marking strips 16, which are used to indicate the position of the first exposed point 5, the second exposed point 12, and other exposed points relative to the distal end of the conveying microcatheter. The marking strips 16 can be marking strips formed by laser marking, or they can be developing marking structures set on the conveying steel pipe 15 or other developing parts of the conveying rod.

[0053] Multiple marker bands 16 can have the same length, and the interval between two adjacent marker bands 16 can be the same. Multiple marker bands 16 are set to correspond to multiple exposed points respectively. The surgeon can determine whether the target exposed point has just moved out of the distal end of the delivery microcatheter based on the positional relationship between the marker band 16 and the cathode imaging element at the distal end of the delivery microcatheter under X-ray, thereby improving the accuracy of the target release position selection.

[0054] Example 3 like Figure 3 and Figure 4 As shown, the delivery microcatheter is used to deliver the implanted spring 3 and the delivery rod, and to form a cathode conductive path; the delivery microcatheter includes a cathode imaging element, a winding filament 19, a braided tube 20, a PTFE inner tube 22, an outer resin layer 23, a cathode needle 24, and a tube seat 25. The cathode imaging element is disposed at the distal end of the delivery microcatheter and is at least partially exposed on the outer surface of the distal end of the delivery microcatheter.

[0055] In this embodiment, the cathode imaging element is a second imaging ring 18. The second imaging ring 18 is used both to indicate the position of the distal end of the delivery microcatheter under X-rays and to serve as the cathode end in the local electrolysis circuit. The outer resin 23 has an annular break at the corresponding position of the second imaging ring 18, so that the second imaging ring 18 is exposed on the outer surface of the distal end of the delivery microcatheter through the annular break, thereby enabling the second imaging ring 18 to come into contact with blood and participate in the local electrolysis circuit.

[0056] The PTFE inner tube 22 passes through the delivery microcatheter and forms an inner cavity for the implanted spring 3 and the delivery rod to move. The PTFE inner tube 22 has a low coefficient of friction, which can provide a smoother delivery channel for the implanted spring 3 and the delivery rod, thereby reducing the frictional resistance when the implanted spring 3 is pushed through the delivery microcatheter.

[0057] The outer resin 23 can be made of TPU, Pebax, PA or a combination thereof, so that the delivery microcatheter forms a transitional structure from soft at the distal end to rigid at the proximal end; through the cooperation of the outer resin 23, the wound filament 19 and the braided tube 20, the delivery microcatheter can take into account distal compliance, proximal delivery and overall flexural strength.

[0058] The winding wire 19 is disposed in the middle layer of the distal soft section of the delivery microcatheter. The winding wire 19 can be a spring structure formed by winding stainless steel wire, which is used to improve the bending resistance and compliance of the distal soft section of the delivery microcatheter. The braided tube 20 is disposed in the middle layer of the proximal end of the delivery microcatheter. The braided tube 20 can be a tubular skeleton structure formed by braiding stainless steel flat wire, which is used to provide a stable skeleton and support for the proximal end of the delivery microcatheter.

[0059] The second developing ring 18 is connected to the winding wire 19, the winding wire 19 is connected to the braided tube 20, and the braided tube 20 is connected to the cathode needle 24. The cathode needle 24 is used to connect to the negative terminal of the power supply. Specifically, the proximal end of the second developing ring 18 can be fixedly connected to the distal end of the winding wire 19 by solder 21, the proximal end of the winding wire 19 can be fixedly connected to the braided tube 20 by solder 21, and the proximal end of the braided tube 20 can be fixedly connected to the cathode needle 24 by solder 21.

[0060] The second developing ring 18, the winding wire 19, the braided tube 20, and the cathode needle 24 together form a cathode conduction path within the delivery microcatheter. When the cathode needle 24 is connected to the negative terminal of the power supply, the second developing ring 18 serves as the cathode end of the distal end of the delivery microcatheter, enabling a local electrolytic circuit to be formed between the target exposed point and the second developing ring 18 near the distal end of the delivery microcatheter.

[0061] The tube seat 25 is located at the proximal end of the delivery microcatheter. The tube seat 25 is used for the delivery rod and implantation spring 3 to enter the delivery microcatheter, and is also used for the operator to hold, flush, or connect external accessories. The cathode needle 24 can be located near the tube seat 25 or inserted into the tube seat 25 to facilitate connection to the negative terminal of an external power supply.

[0062] In one alternative embodiment, the inner diameter of the delivery microcatheter is adapted to the outer diameter of the implanted spring 3, allowing the implanted spring 3 to move smoothly axially within the delivery microcatheter, while placing the non-target exposed point within the delivery microcatheter in a relatively confined liquid exchange environment; this structure can reduce the possibility of effective electrolytic reactions forming near the non-target exposed point while ensuring smooth delivery.

[0063] Example 4 like Figures 5-8 As shown, in use, the implanted spring 3 can be first loaded into the inlet sheath 26. The inlet sheath 26 is used to constrain and protect the implanted spring 3 before it enters the delivery microcatheter. Then, the inlet sheath 26 is connected to the proximal end of the delivery microcatheter, and the implanted spring 3 is pushed from the inlet sheath 26 into the delivery microcatheter through the delivery rod.

[0064] The operator delivers the microcatheter through the vascular access to the vicinity of the aneurysm cavity, so that the distal end of the microcatheter enters or approaches the aneurysm cavity; the operator continues to push the delivery rod, so that the implanted spring 3 is gradually delivered from the distal end of the microcatheter into the aneurysm cavity. During the pushing process, the operator can observe the positional relationship between the marker band 16, the second imaging ring 18 and the first imaging ring 10 through X-ray, and determine whether the first exposed point 5, the second exposed point 12 or other exposed points have reached the outer side of the distal end of the microcatheter.

[0065] When either the first exposed point 5 or the second exposed point 12 is selected as the target exposed point and removed from the distal end of the delivery microcatheter, the anode conductive tube 17 is connected to the positive terminal of the power supply, and the cathode needle 24 is connected to the same negative terminal of the power supply. At this time, the current is conducted sequentially through the anode conductive tube 17, the anode wire 11 and the anti-unwinding wire 2 to the target exposed point, and then through the blood to the second imaging ring 18, which is the cathode end, and then through the winding wire 19, the braided tube 20 and the cathode needle 24 back to the negative terminal of the power supply.

[0066] Since the second imaging ring 18 is located at the distal end of the delivery microcatheter and is at least partially exposed, and the target exposed point is located outside the distal end of the delivery microcatheter, the target exposed point and the second imaging ring 18 can form a local electrolytic circuit through blood near the distal end of the delivery microcatheter; in this local electrolytic circuit, the target exposed point is corroded and fractured as an electrochemical fracture area, causing the implanted spring 3 to separate at the target exposed point. After separation, the implanted spring 3 located on the distal side of the target exposed point remains in the aneurysm cavity, and the structure located on the proximal side of the target exposed point can be retracted with the delivery rod.

[0067] By selecting the first exposed point 5, the second exposed point 12, or other exposed points as the target release positions, implanted springs 3 of different lengths can be released. The implanted spring 3 can have a two-dimensional or three-dimensional configuration. When the implanted spring 3 has a two-dimensional configuration, it is suitable for forming a relatively regular annular or coiled filling structure in the aneurysm cavity. When the implanted spring 3 has a three-dimensional configuration, it is suitable for forming a spatial support and basket structure in the aneurysm cavity.

[0068] In one embodiment, the power supply voltage can be from 8V to 24V; in a preferred embodiment, the power supply voltage is 24V, and the single output time of the power control unit does not exceed 2 seconds; under 24V test conditions, the target exposed point can complete electrochemical fracture within 2 seconds. Compared with the conventional 24V electrolytic decomposition structure with a decomposition time of about 5 seconds, this embodiment can shorten the decomposition waiting time.

[0069] The output time of less than 2 seconds can be used as the single output control time. After a single output, the target exposed point can be confirmed by the retraction conveying system to see if it has been freed. If the target exposed point is not completely freed after a single output, a short output can be performed again. By combining short output with retraction confirmation, the risk of cumulative corrosion of non-target exposed points caused by long-term continuous power supply can be reduced.

[0070] The lengths of the first exposed point 5, the second exposed point 12, and other exposed points, the diameter of the metal core at the exposed point, and the axial distance between the second developing ring 18 and the target exposed point affect the desorption speed. Among them, the length of the exposed point and the diameter of the metal core affect the amount of corrosion required for electrochemical corrosion fracture, and the axial distance between the second developing ring 18 and the target exposed point affects the length of the local electrolytic circuit and the current density near the target exposed point.

[0071] To reduce the risk of misidentification of non-target exposed points, the spacing between two adjacent exposed points is preferably not less than 5 mm, so as to reduce the possibility that adjacent exposed points are simultaneously located in the local high-efficiency electrolysis area at the distal end of the delivery microcatheter; at the same time, multiple marking bands 16 are respectively set with multiple exposed points, which can help the operator to make the target exposed point just exposed on the outer side of the distal end of the delivery microcatheter.

[0072] When the target exposed point is just exposed outside the distal end of the delivery microcatheter, the distance between the target exposed point and the second imaging ring 18 is relatively close, and the local electrolytic reaction is more concentrated, while the non-target exposed point is not in this local high-efficiency electrolytic area; since the power control unit adopts short-time output control, and the single output time is preferably no more than 2 seconds, the risk of non-target exposed points being mis-desorbed due to continuous electrochemical corrosion can be reduced.

[0073] The controllable segmented electrolytic spring coil system of this embodiment does not rely on the mechanical snap-fit ​​structure between adjacent segmented spring coils to achieve separation. Instead, it uses the exposed second imaging ring 18 at the distal end of the delivery microcatheter as the cathode and the target exposed point on the anti-unwinding wire 2 as the anode fracture region to form a local electrolytic circuit. This embodiment can concentrate the electrochemical reaction near the target exposed point while retaining the selectable length release capability of the spring coil, thus achieving faster electrolytic separation.

[0074] The anti-unwinding wire 2 simultaneously serves as an anti-unwinding, conductive, and segmented fracture carrier, which can reduce the impact of additional mechanical release components outside the implanted spring 3 on the flexibility and passability of the spring coil; the second imaging ring 18 simultaneously serves as a distal imaging and cathode conduction function, allowing the imaging structure and electrolysis structure of the delivery microcatheter to be reused, reducing additional electrode components.

[0075] In summary, compared with the prior art, the controllable segmented release spring coil system proposed in this application has the following beneficial effects: By setting a first exposed point 5 and a second exposed point 12 separated by an insulating area on the anti-unwinding wire 2, and making the conveying rod connected to the anti-unwinding wire 2 and the cathode developing element at the distal end of the conveying microcatheter connected to the conductive support structure, when the target exposed point moves out of the distal end of the conveying microcatheter, the target exposed point can form a local electrolytic circuit with the cathode developing element near the distal end of the conveying microcatheter, so that the electrolytic reaction is concentrated at the target exposed point, reducing the long waiting time for release caused by the far position of the cathode and the non-concentrated reaction at the target release point.

[0076] By setting a marker strip 16 on the delivery rod to indicate the position of the exposed point relative to the distal end of the delivery microcatheter, and setting multiple marker strips 16 corresponding to multiple exposed points, the operator can determine under X-ray whether the first exposed point 5, the second exposed point 12, or other target exposed points expose the distal end of the delivery microcatheter, thereby improving the accuracy of the release position determination. At the same time, by ensuring that the distance between two adjacent exposed points is not less than 5mm, and by coordinating with the power control unit to ensure that the single output time does not exceed 2 seconds under 24V voltage conditions, the risk of accidental corrosion or synchronous breakage of non-target exposed points due to prolonged power supply or excessive distance can be reduced.

[0077] By setting the cathode developing element as the second developing ring 18, and making the second developing ring 18 form a negative electrode conduction path through the winding wire 19, the braided tube 20 and the cathode needle 24, the second developing ring 18 can serve as both a developing positioning structure for the distal end of the delivery microcatheter and a cathode end of the local electrolysis circuit to participate in the release process, thus realizing the reuse of the developing structure and the cathode structure. The first exposed point 5 and the second exposed point 12 on the anti-unwinding wire 2 are formed by removing the insulation layer, which can limit the electrolytic breakage position while maintaining the insulation isolation of the non-exposed area, and take into account the flexibility of the spring coil, the anti-unwinding ability and the segmented release stability.

[0078] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0079] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A controllable segmented release spring coil system, characterized in that, Includes implanted spring (3), anti-unwinding wire (2), delivery rod and delivery microcatheter; The anti-decoupling wire (2) is inserted into the implanted spring (3), and a first exposed point (5) and a second exposed point (12) separated by an insulating area are provided along the length direction of the implanted spring (3). The conveying rod is connected to the anti-decoupling wire (2) and is used to connect to the positive terminal of the power supply. The distal end of the delivery microcatheter is provided with an exposed cathode developing element, which is connected to the conductive support structure inside the delivery microcatheter and is used to connect to the negative terminal of the power supply. The delivery rod is provided with a marking strip (16) for indicating the position of the exposed point relative to the distal end of the delivery microcatheter; when any exposed point moves away from the distal end of the delivery microcatheter, the exposed point forms a local electrolytic circuit with the cathode imaging element so that the implanted spring (3) separates at the exposed point.

2. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, The cathode developing element is a second developing ring (18), and the delivery microcatheter includes an outer resin layer (23). The outer resin layer (23) has an annular break at the corresponding position of the second developing ring (18), and the second developing ring (18) is exposed on the outer surface of the distal end of the delivery microcatheter through the annular break.

3. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, The conductive support structure includes a winding wire (19) and a braided tube (20). The cathode developing element is connected to the winding wire (19), the winding wire (19) is connected to the braided tube (20), and the braided tube (20) is connected to the cathode needle (24). The cathode needle (24) is used to connect to the negative terminal of the power supply.

4. The controllable segmented electrically decoupling spring coil system according to claim 3, characterized in that, The proximal end of the cathode developing element is welded and fixed to the distal end of the winding wire (19), the proximal end of the winding wire (19) is welded and fixed to the braided tube (20), and the proximal end of the braided tube (20) is welded and fixed to the cathode needle (24).

5. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, Multiple marker bands (16) have the same length and the interval between two adjacent marker bands (16) is the same. Multiple marker bands (16) are set to correspond to multiple exposed points respectively, and are used to determine whether the target exposed point exposes the distal end of the delivery microcatheter under X-ray.

6. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, The distance between two adjacent exposed points shall not be less than 5mm.

7. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, It also includes a power control unit, which is used to provide short-time output to the local electrolysis circuit, and the power control unit is set to output for no more than 2 seconds at a time under 24V voltage conditions.

8. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, The anti-derotation wire (2) includes a metal core and an insulating layer covering the outside of the metal core. The first exposed point (5) and the second exposed point (12) are both electrolytic exposure areas formed after the insulating layer is removed.

9. The controllable segmented electrically decoupling spring coil system according to claim 8, characterized in that, The metal core is a 316LVM stainless steel core, and the insulation layer is a PI insulation layer. The first exposed point (5) and the second exposed point (12) are both formed by laser ablation of the PI insulation layer. The length of the first exposed point (5) is 0.015-0.035mm, the length of the second exposed point (12) is 0.03mm-0.07mm, the diameter of the 316LVM stainless steel core is 0.012mm-0.018mm, and the thickness of the PI insulation layer is 3μm-8μm.

10. The controllable segmented electrically decoupling spring coil system according to claim 1, characterized in that, The conveying rod includes an anode wire (11) and an anode conductive tube (17). The anode conductive tube (17) is connected to the proximal end of the anode wire (11), and the distal end of the anode wire (11) is connected to the anti-unwinding wire (2). The anode conductive tube (17) is used to connect to the positive terminal of the power supply.

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