Spring ring

Abstract

The invention discloses a spring ring, and belongs to the technical field of medical instruments. The spring ring comprises a spring ring body, and the spring ring body comprises a supporting part and a filling part. The supporting part has a shape memory effect, and can adapt to the shape of an opening of a tumor sac and support the neck of the tumor sac during expansion; one part of the supporting part is made of a degradable material, and the other part of the supporting part is made of a non-degradable material; the tumor sac is filled with the filling part, and the filling part is made of a degradable material. The spring ring can reduce the space occupying effect and can be stably implanted into the aneurysm sac.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a spring coil. Background Art

[0002] Intracranial aneurysms are formed by local bulging of the arterial wall. As the aneurysm grows, the compliance of the vascular wall decreases, the tension increases, and the aneurysm ruptures. Ruptured aneurysms can cause cerebral vasospasm, impaired consciousness, neurological dysfunction, and even death. Currently, the main surgical methods for intracranial aneurysms include microsurgical clipping, intravascular intervention, intracranial and extracranial arterial bypass surgery, and coil embolization. Among the many options, coil embolization has the advantages of safety, reliability, stable implantation, and convenient delivery.

[0003] At present, there are three main types of coils: the first type is a pre-shaped bare metal coil, which is prefabricated with platinum-tungsten alloy material into a two-dimensional or three-dimensional structure; the second type is a bio-modified coil with a surface covered with bioactive materials, which reduces the space-occupying effect by covering the surface of the metal coil with degradable biomaterials; the third type is a highly swellable hydrogel coil, which adds hydrophilic polypropylene hydrogel inside the metal coil. After implantation, the hydrogel absorbs a large amount of water and expands rapidly, so that the coil completely fills the cavity to reduce the recanalization rate of the aneurysm. The above three types of coils, whether bare metal coils or bio-modified coils and hydrogel coils prepared on their basis, can treat related diseases after filling, but because the large amount of residual metal will still remain in the body for a long time, its safety and space-occupying effect have not been completely solved.

[0004] If the spring coil is made of a degradable material, such as a magnesium alloy spring coil, the treatment effect will be affected because the single degradation cycle and the disease healing cycle cannot be perfectly matched.

[0005] It is also important that aneurysm filling devices such as coils need to be maintained in the aneurysm for a long time. However, aneurysms with larger openings have difficulties in placing and maintaining aneurysm filling devices in the aneurysm sac, especially for small and relatively thin coils. Before the aneurysm sac is completely embolized, the relatively compliant coils will inevitably lack sufficient mechanical strength to resist the impact of blood to maintain their filling posture in the aneurysm sac, so that they herniate from the aneurysm sac.

[0006] Therefore, a spring coil is needed to solve the above problems. Summary of the invention

[0007] The object of the present invention is to provide a spring coil which can reduce the space-occupying effect and can be stably implanted in the aneurysm sac.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] A spring coil comprises a spring coil body, wherein the spring coil body comprises:

[0010] The support part has a shape memory effect, and can adapt to the shape of the opening of the tumor sac when expanded and support the neck of the tumor sac; a part of the support part is made of a degradable material, and the other part is made of a non-degradable material;

[0011] The filling part is filled in the tumor capsule, and the filling part is made of degradable material.

[0012] In some possible implementations, the support portion is woven into a mesh by first braided wires and second braided wires, the first braided wires are made of a degradable material having a shape memory effect, and the second braided wires are made of a non-degradable material having a shape memory effect.

[0013] In some possible implementations, the first braided wire is formed by electrospinning a polymer material; and / or, the second braided wire is a nickel-titanium wire; and / or, the filling portion is a magnesium alloy wire.

[0014] In some possible implementations, the area of ​​the second braided wire accounts for 60%-80% of the total area of ​​the support portion, and the first braided wire is elastic to adapt to the shape of the opening of the tumor capsule.

[0015] In some possible implementations, the support portion can expand into an umbrella shape and at least a portion of the support portion is supported on the inner wall of the tumor capsule.

[0016] In some possible implementations, a core wire made of a degradable material is further included, wherein the core wire coincides with the center line of the spring coil body, one end of the core wire is connected to the proximal end of the support portion, and the other end is connected to the distal end of the filling portion.

[0017] In some possible implementations, a procoagulant drug is provided on the surface of the core wire.

[0018] In some possible implementations, a plurality of recessed grooves are arranged spirally and spaced apart along the length direction on the surface of the core wire, and the procoagulant drug is placed in the recessed grooves.

[0019] In some possible implementations, the depth of the recessed groove is h, and the diameter of the core wire is D, wherein h is 0.3D to 0.6D, and D is 0.05 mm to 0.1 mm.

[0020] In some possible implementations, the cross-sectional area of ​​the recessed groove close to the groove opening along the direction from the groove opening to the groove bottom is not less than the cross-sectional area close to the groove bottom.

[0021] In some possible implementations, the total volume of the plurality of recessed grooves accounts for 1%-5% of the volume of the spring coil.

[0022] In some possible implementations, the recessed groove is made by a plasma etching method, and the procoagulant drug is disposed on the core wire that has been plasma etched.

[0023] Beneficial effects of the present invention:

[0024] The present invention provides a spring coil, which comprises a spring coil body including a supporting portion and a filling portion. During the process of releasing the spring coil into the aneurysm sac, the filling portion fills the interior of the aneurysm sac, and then continues to push and open the supporting portion with a shape memory effect, so that the supporting portion expands to a preset state, that is, the supporting portion adapts to the shape of the opening of the aneurysm sac, seals at the opening and supports the neck of the aneurysm sac, thereby preventing blood from flowing into the aneurysm sac to flush the filling portion, preventing the spring coil from being displaced, and being able to be stably implanted in the aneurysm sac to avoid the spring coil herniating from the aneurysm sac before complete embolism is formed.

[0025] Since part of the support part is made of degradable material, the other part is made of non-degradable material, and the filling part is made of degradable material. After the coil is implanted, the support part is located at the opening and will come into contact with the blood in the blood vessel. Compared with the filling part in the tumor capsule, the degradable part of the support part will degrade faster to a certain extent, and finally the non-degradable part of the support part will be left to support the neck of the tumor capsule. On the one hand, the number of coils remaining in the body is reduced to avoid problems such as safety and space-occupying effect caused by their long-term stay in the body. On the other hand, the filling part and part of the support part degrade in a gradient to a certain extent, overcoming the problem of too fast degradation, so as to match the disease healing cycle and ensure the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of a spring coil provided by a specific embodiment of the present invention in a state of being transported in a microcatheter;

[0027] Figure 2 is a schematic diagram of a coil provided by a specific embodiment of the present invention in an expanded state within a tumor sac;

[0028] Figure 3 is a schematic diagram of a filling portion and a core wire provided in a specific embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the arrangement of the concave grooves on the core wire provided by a specific embodiment of the present invention;

[0030] Figure 5 It is a schematic diagram of the release of the procoagulant drug when the core wire is in a bent state provided by a specific embodiment of the present invention;

[0031] Figure 6 is a side view of a concave groove of a core wire provided in a specific embodiment of the present invention;

[0032] Figure 7 yes Figure 6 Enlarged view of point A.

[0033] In the figure:

[0034] 1. Spring coil body; 11. Support part; 12. Filling part;

[0035] 2. core wire; 21. recessed groove; 211. first groove portion; 212. second groove portion;

[0036] 3. Procoagulant drugs;

[0037] 4. Guide wire; 5. Limiting ball; 6. Microcatheter;

[0038] 100, blood vessels; 200, tumor cyst; 300, opening. DETAILED DESCRIPTION

[0039] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0040] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0042] like Figure 1-Figure 3 As shown, this embodiment provides a spring coil, including a spring coil body 1 and a core wire 2. The core wire 2 is inserted into the coil body of the spring coil body 1, and the head and tail ends of the core wire 2 correspond to the head and tail ends of the spring coil body 1, and are connected to form a whole through a welding process or an adhesive technology. The core wire 2 is at the center of the spring coil, that is, the center line of the core wire 2 coincides with the center line of the spring coil body 1. The spring coil is transported in the blood vessel 100 through the microcatheter 6, and the core wire 2 of the spring coil is fixed in the microcatheter 6 through the limiting ball 5, and the core wire 2 and the limiting ball 5 are connected by the guide wire 4. When transported to the position of the tumor capsule 200, the guide wire 4 breaks, thereby separating the limiting ball 5 and the core wire 2, and the spring coil enters the tumor capsule 200. Please refer to the prior art for details, which will not be repeated. By setting the core wire 2, the spring coil is subjected to more uniform force during the transportation stage.

[0043] The coil body 1 includes a support portion 11 and a filling portion 12. One end of the core wire 2 is connected to the proximal end of the support portion 11, and the other end is connected to the distal end of the filling portion 12. The support portion 11 has a shape memory effect, and can adapt to the shape of the opening 300 of the tumor capsule 200 when expanded and support the neck of the tumor capsule 200. Exemplarily, the support portion 11 can expand into an umbrella shape and at least part of the support portion 11 is supported on the inner wall of the tumor capsule 200. A part of the support portion 11 is made of a degradable material, and the other part is made of a non-degradable material. The filling portion 12 is filled inside the tumor capsule 200, and the filling portion 12 is made of a degradable material, such as a magnesium alloy wire.

[0044] Optionally, the support portion 11 is woven into a mesh by first braided wires and second braided wires, the first braided wires are made of a degradable material having a shape memory effect, such as a polymer filament formed by electrospinning a polymer material; the second braided wires are made of a non-degradable material having a shape memory effect, such as a nickel-titanium wire.

[0045] In particular, the area of ​​the second braided wire accounts for 60%-80% of the total area of ​​the support portion 11, that is, the nickel-titanium metal wire is used as the main braided wire, and the polymer filaments are interspersed therein as auxiliary braided wires. In this mixed braided structure, the first braided wire, namely the polymer filaments, provides excellent elasticity and shape memory effect, so that the support portion 11 can adapt to the shape of the opening 300 of the tumor sac 200 when expanded, and thus more stably support the neck of the tumor sac 200. The polymer filaments with shape memory effect can be polyurethane, polylactic acid polymer materials formed by electrospinning, and the proximal support portion 11 abuts against the inner wall of the aneurysm sac 200 after expansion.

[0046] Optionally, the core wire 2 is made of a degradable material, such as a magnesium alloy material.

[0047] By providing a spring coil body 1 including a supporting portion 11 and a filling portion 12, during the process of releasing the spring coil into the aneurysm sac 200, the filling portion 12 is filled in the aneurysm sac 200, and then the supporting portion 11 with a shape memory effect is continuously pushed open, so that the supporting portion 11 expands to a preset state, that is, the supporting portion 11 adapts to the shape of the opening 300 of the aneurysm sac 200, is sealed at the opening 300 and supported on the neck of the aneurysm sac 200, thereby preventing blood flow from flowing into the aneurysm sac 200 to flush the spring coil and preventing the spring coil from being displaced. The spring coil can be stably implanted in the aneurysm sac 200, and herniation of the spring coil from the aneurysm sac 200 is avoided before complete embolism is formed.

[0048] Since part of the support portion 11 is made of a degradable material, the other part is made of a non-degradable material, and the filling portion 12 is made of a degradable material. After the coil is implanted, the support portion 11 located at the opening 300 will come into contact with the blood in the blood vessel 100. Compared with the filling portion 12 in the tumor capsule 200, the degradable part of the support portion 11 will degrade faster to a certain extent, and then the filling portion 12 and the core wire 2 will degrade. Finally, the non-degradable part of the support portion 11 will remain in the body to support the neck of the tumor capsule 200, that is, the coil is a gradient-degradable embolization treatment device. On the one hand, it reduces the number of coils remaining in the body and avoids problems such as safety and space-occupying effect caused by its long-term stay in the body. On the other hand, the filling portion 12 and part of the support portion 11 degrade in a gradient to a certain extent, overcoming the problem of too fast degradation, so as to match the disease healing cycle and ensure the treatment effect.

[0049] like Figure 4-Figure 7As shown, the surface of the core wire 2 is provided with a procoagulant drug 3, and the entire or partial surface of the core wire 2 is covered with the procoagulant drug 3. The procoagulant drug 3 can be a procoagulant substance, which is one or more of snake venom hemocoagulase, vitamin K, freeze-dried human coagulation factor VIII, prothrombin complex, thrombin and freeze-dried human fibrinogen, aminobenzoic acid, tranexamic acid, aprotinin and aminocaproic acid, anloxin and phenolsulfonamide. In one embodiment, the surface of the core wire 2 is spirally arranged along the length direction, and the procoagulant drug 3 is placed in the recessed groove 21. The cross-sectional area of ​​the recessed groove 21 near the groove side along the groove mouth to the groove bottom direction is not less than the cross-sectional area near the groove bottom side, such as the recessed groove 21 is inverted cone shape. Exemplarily, the recessed groove 21 includes a first groove portion 211 and a second groove portion 212 along the groove mouth to the groove bottom direction, the first groove portion 211 gradually shrinks from the groove mouth to the groove bottom, and the second groove portion 212 is a groove located at the bottom of the first groove portion 211. Through the arrangement and shape structure design of the recessed grooves 21 on the core wire 2, on the one hand, when the soft core wire 2 is bent and filled with the spring coil, the recessed grooves 21 are deformed due to the bending of the core wire 2, and the notches of some recessed grooves 21 are further expanded, thereby immediately releasing the procoagulant drug 3 into the tumor sac 200, so that thrombus is generated in the far area of ​​the unfilled spring coil, thereby achieving an ideal filling effect with a smaller volume of the spring coil. On the other hand, the notches of some recessed grooves 21 are squeezed and contracted, thereby playing a role of sustained drug release. The procoagulant drug 3 in these recessed grooves 21 mainly relies on blood infiltration to generate thrombus in the near area of ​​the core wire 2 to fix the filling posture of the spring coil.

[0050] The concave groove 21 is made by plasma etching, and the procoagulant drug 3 is arranged on the plasma-etched core wire 2. The depth of the concave groove 21 is h, and the diameter of the core wire 2 is D, wherein h is 0.3D to 0.6D, and D is 0.05mm to 0.1mm, such as 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm or 0.1mm. The concave groove 21 on the surface of the core wire 2 is realized by plasma etching and other methods, and the depth of the appropriate concave groove 21 is controlled by setting plasma processing parameters, and the etched core wire 2 is immersed in a solution of the procoagulant drug 3 or the concave groove 21 is loaded with drugs by spraying. The formation of depressions on the surface of the core wire 2 and then covering the procoagulant drug 3 not only overcomes the problem of poor bonding between the drug coating and the untreated metal wire surface in the prior art, but also controls the drug loading by adjusting the depth and number of the depressions 21, so that an excessive amount of the procoagulant drug 3 will not cause harm to the human body. The total volume of the multiple depressions 21 accounts for 1%-5% of the volume of the spring coil.

[0051] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A spring coil, characterized in that: It comprises a spring ring body (1), wherein the spring ring body (1) comprises: The support portion (11) has a shape memory effect and can block the opening of the tumor sac (200) and support the neck of the tumor sac (200) when expanded; a part of the support portion (11) is made of a degradable material, and another part is made of a non-degradable material; The filling part (12) is filled in the tumor capsule (200), and the filling part (12) is made of a degradable material.

2. The spring coil according to claim 1, characterized in that: The support part (11) is woven into a mesh shape by first braided wires and second braided wires, the first braided wires are made of a degradable material having a shape memory effect, and the second braided wires are made of a non-degradable material having a shape memory effect.

3. The spring coil according to claim 2, characterized in that: The first braided wire is formed by electrostatic spinning of a polymer material; and / or, the second braided wire is a nickel-titanium metal wire; and / or, the filling part (12) is a magnesium alloy metal wire.

4. The spring coil according to claim 2, characterized in that: The area of ​​the second braided wire accounts for 60%-80% of the total area of ​​the support portion (11), and the first braided wire has elasticity to adapt to the shape of the opening of the tumor capsule (200).

5. The spring coil according to claim 1, characterized in that: The support portion (11) can expand into an umbrella shape, and a portion of the support portion (11) is supported on the inner wall of the tumor capsule (200).

6. The spring coil according to any one of claims 1 to 5, characterized in that: It also includes a core wire (2) made of a degradable material, wherein the core wire (2) coincides with the center line of the spring coil body (1), one end of the core wire (2) is connected to the proximal end of the support portion (11), and the other end is connected to the distal end of the filling portion (12).

7. The spring coil according to claim 6, characterized in that: The surface of the core wire (2) is provided with a coagulant-promoting drug (3).

8. The spring coil according to claim 7, characterized in that: The surface of the core wire (2) is provided with a plurality of recessed grooves (21) arranged in a spiral pattern at intervals along the length direction, and the procoagulant drug (3) is contained in the recessed grooves (21).

9. The spring coil according to claim 8, characterized in that: The depth of the recessed groove (21) is h, and the diameter of the core wire (2) is D, wherein h is 0.3D to 0.6D, and D is 0.05mm to 0.1mm.

10. The spring coil according to claim 8, characterized in that The cross-sectional area of ​​the concave groove (21) close to the groove opening along the direction from the groove opening to the groove bottom is not less than the cross-sectional area close to the groove bottom.

11. The spring coil according to claim 8, characterized in that The total volume of the plurality of recessed grooves (21) accounts for 1%-5% of the volume of the spring coil.

12. The spring coil according to claim 8, characterized in that The recessed groove (21) is made by a plasma etching method, and the procoagulant drug (3) is arranged on the core wire (2) that has been plasma etched.

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