Spring coils and their anti-untwisting components

Abstract

The present invention provides a spring coil and its anti-untwisting component. The rigidity of the end portion of the anti-untwisting component is lower than that of the middle portion. This achieves the desired "hard center, soft ends" effect while still providing anti-untwisting properties. The spring coil of the present invention, incorporating the anti-untwisting component, exhibits a "hard center, soft ends" flexibility, meeting the flexibility requirements of different coil locations during embolization.

Description

Technical Field

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

[0002] With the continuous improvement of people's living standards, the number of patients with cerebral aneurysms has increased. The main treatment methods for cerebral aneurysms are surgical clipping and endovascular intervention. Due to the high risks of surgery, endovascular intervention has become increasingly popular among doctors and patients in recent years. Currently, endovascular intervention mainly uses coil embolization therapy, which involves implanting several coils into the aneurysm to redirect blood flow and ultimately heal the aneurysm.

[0003] Existing coil products typically consist of three components when implanted: an embolic spring, a distal cap, and an anti-untwisting component. The anti-untwisting component primarily serves a simple function, connecting the two ends of the embolic spring and providing an anti-untwisting mechanism. This prevents the embolic spring from straightening due to external forces during implantation and use, thereby maintaining its spring structure.

[0004] Furthermore, during the embolization process, different parts of the coil require different softness. The distal end is usually the first to contact the aneurysm wall, and this distal end has the potential to flip (change its extension direction) during the embolization process, so it requires higher softness. The middle part of the coil needs to be stably formed and requires slightly higher hardness. The proximal end of the coil is used for internal packing after basket formation and also requires better softness. In other words, the coil needs to be "hard in the middle and soft at both ends" during the embolization process. However, existing coil products all achieve the purpose of adjusting the softness of the implanted coil by processing the embolization spring portion, such as changing the softness of the spring wire itself. However, adjusting the softness of the implanted coil by only processing the embolization spring portion makes it difficult to achieve the "hard in the middle and soft at both ends" state of the coil in terms of technology. Summary of the Invention

[0005] The object of the present invention is to provide a spring coil and its anti-unrotation component, which can make the anti-unrotation component present a "hard in the middle and soft at both ends" state effect, so that the softness of the spring coil with the anti-unrotation component also presents a "hard in the middle and soft at both ends" state effect, meeting the softness requirements of different parts of the spring coil during the embolization process.

[0006] To achieve the above object, the present invention provides an anti-unrotation component for a spring coil, wherein the anti-unrotation component has two ends and a middle portion extending between the two ends, wherein the stiffness of the middle portion is greater than the stiffness of each of the end portions.

[0007] Optionally, the anti-untwisting component includes at least two strands of wire to form the two end portions and the middle portion, and a structure formed by the wires at the end portions is different from a structure formed by the wires at the middle portion.

[0008] Optionally, the wires at the end portions are arranged in parallel with each other to form end parallel segments, and the wires at the middle portion are at least partially entangled with each other to form at least one braided segment.

[0009] Optionally, the middle portion includes multiple braided segments and at least one middle parallel segment, the braided segments and the middle parallel segments are arranged alternately, and the wires between adjacent braided segments are parallel to each other to form the middle parallel segment.

[0010] Optionally, the length of the braided segment is 3 to 4 times the length of the middle parallel segment.

[0011] Optionally, the middle portion includes a plurality of braided segments that are arranged continuously and have different structures.

[0012] Optionally, the multiple braided segments are different in at least one of their lengths, winding methods, and arrangement structures in the longitudinal cross-section, so that the structures of the multiple braided segments are not completely the same.

[0013] Optionally, the middle portion is divided into at least two sections along the axial direction of the anti-untwisting component, the number of strands of the wire in each section is the same or different, and the number of strands of the wire at the end is less than or equal to the number of strands of the wire in each section of the middle portion.

[0014] Optionally, the anti-untwisting component is a cylindrical structure, and the outer diameter of the end portion is smaller than the outer diameter of the middle portion.

[0015] Optionally, the anti-untwisting component is a cylindrical structure, the end portion is a hollow cylindrical structure, and the middle portion is a solid cylindrical structure.

[0016] Optionally, the length of the middle portion is 60% to 80% of the total length of the anti-untwisting component, and the length of each of the end portions is 10% to 20% of the total length of the anti-untwisting component.

[0017] Optionally, the material of the anti-untwisting component includes polymer material and / or metal material.

[0018] The present invention also provides a spring coil, which includes a spring and the anti-unrotation component described in the present invention. The anti-unrotation component is inserted into the interior of the spring, and the two ends of the anti-unrotation component are respectively connected to the two ends of the spring.

[0019] Optionally, the spring coil further includes connecting pieces provided at both ends of the spring for connecting the spring coil and the anti-untwisting component.

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0021] 1. The anti-untwisting component of the present invention has a stiffness at its ends that is smaller than that at its middle portion, thereby achieving the effect of "hard in the middle and soft at both ends" while achieving the anti-untwisting effect.

[0022] 2. The spring coil of the present invention has the anti-untwisting component of the present invention. Therefore, the softness of the spring coil of the present invention also presents a state effect of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, so as to achieve the purpose of making the distal end of the spring coil easier to flip, the middle part more stably formed, and the proximal end easier to fill during the implantation process, thereby improving the filling density of the spring coil and making the implantation process smoother.

[0023] 3. Since the middle portion of the anti-untwisting component of the present invention can have different stiffnesses, the stiffness of the anti-untwisting component can show a certain variation pattern, thereby making the softness of the spring coil also show a certain variation pattern, thereby meeting the different softness requirements of multiple parts of the spring coil during the embolization process. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic cross-sectional structural diagram of the anti-untwisting component and the spring coil according to the first embodiment of the present invention.

[0025] Figures 2A-2B It is a schematic cross-sectional structural diagram of the anti-untwisting component and the spring coil according to the second embodiment of the present invention.

[0026] Figure 3 It is a schematic cross-sectional structural diagram of the anti-untwisting component and the spring coil according to the third embodiment of the present invention.

[0027] Figures 4A-4B It is a schematic cross-sectional structural diagram of the anti-untwisting component and the spring coil according to the fourth embodiment of the present invention.

[0028] Figure 5 It is a schematic cross-sectional structure diagram of the anti-unrotation component and the spring coil according to the fifth embodiment of the present invention.

[0029] Figures 6A-6C It is a schematic cross-sectional structure diagram of the anti-unrotation component and the spring coil according to the sixth embodiment of the present invention.

[0030] The reference numerals therein are as follows:

[0031] 1-spring; 2-anti-untwisting component; 2a, 2c-ends of the anti-untwisting component; 2b-middle part of the anti-untwisting component; 3-connector; 22, 22a-end parallel sections; 21-braided section; 22b-middle part parallel sections; 21a-first braided section; 21b-second braided section; 23-solid cylinder with small outer diameter; 24-solid cylinder with large outer diameter; 25-hollow cylinder; 26-wire material (also called silk thread) used to form the middle part, 27-wire material (also called silk thread) used to form the end part; 26a, 26b, 26c-wires used to form different sections of the middle part. DETAILED DESCRIPTION

[0032] To make the objectives and features of the present invention more readily apparent, the technical solutions of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in various forms and should not be limited to the embodiments described. Furthermore, the term "and / or" herein refers to either or both of the above.

[0033] Example 1

[0034] Please refer to Figure 1 This embodiment provides an anti-untwisting component 2 for a spring coil, the anti-untwisting component 2 having two end portions 2a, 2c and a middle portion 2b extending between the two end portions 2a, 2c. The anti-untwisting component 2 includes at least two strands of wire (also referred to as threads) to form the two end portions 2a, 2c and the middle portion 2b, and the structure formed by the wires at the end portions 2a, 2c is different from the structure formed by the wires at the middle portion 2b. Each wire extends from one end portion 2a of the anti-untwisting component 2 along the axial direction of the anti-untwisting component 2 to the other end portion 2c, thereby making the number of wire strands in the middle portion 2b equal to the number of wire strands at the two end portions 2a, 2c.

[0035] The anti-untwisting component 2 of this embodiment is divided into an end parallel segment 22 constituting the two end portions 2a and 2c, and a braided segment 21 constituting the middle portion 2b. The braided segment 21 refers to a structure formed by winding the strands of wire together using the same braiding or knotting method, while the end parallel segment 22 refers to a structure formed by arranging the strands of wire in parallel and not entangled with each other. The middle portion 2b formed by the braided segment 21 has greater rigidity (or better) and less flexibility (or poorer), while the end portions 2a and 2c formed by the end parallel segment 22 have less rigidity (or poorer) and greater flexibility (or better). That is to say, in the anti-untwisting component 2 of this embodiment, since the structure formed by all the wire materials of the two end portions 2a and 2c is different from the structure formed by all the wire materials of the middle portion 2b, the overall stiffness of the middle portion 2b is greater than the overall stiffness of the end portions 2a and 2c, thereby achieving the effect of "hard in the middle and soft at both ends", and the stiffness of the middle portion 2b can be uniform or uneven, and the stiffness of the end portions 2a and 2c can be uniform or uneven.

[0036] In addition, the material of the wire of the anti-untwisting component 2 includes but is not limited to non-degradable polymer materials (i.e., polymer materials) or non-degradable metal materials including alloys, and the polymer materials include but are not limited to polypropylene (PP), polyethylene (PE) and polyisoprene (PI), etc.; the metal materials include but are not limited to nickel-titanium alloy, platinum-tungsten alloy, titanium-nickel-copper alloy, titanium-nickel-iron alloy, titanium-nickel-chromium alloy, copper-nickel alloy, copper-aluminum alloy, copper-zinc alloy, zinc alloy, magnesium alloy, etc.

[0037] The length L1 of the middle portion 2b (i.e., the length of the braided segment 21) accounts for 60% to 80% of the overall length (i.e., the total length) L of the anti-untwisting component 2; the lengths of the end portions 2a and 2c are both L2 (i.e., the length of one end parallel segment 22), and L2 accounts for 10% to 20% of the overall length (i.e., the total length) L of the anti-untwisting component 2.

[0038] In addition, in this embodiment, the lengths of the ends 2a and 2c connected to the two sides of the middle portion 2b are equal or substantially equal, and the structures formed by the arrangement of the silk threads are the same (for example, the spacing between the two parallel strands of silk threads in the two ends 2a and 2c is the same). The anti-untwisting component 2 as a whole has a structure that is soft at both ends and hard in the middle, and is generally symmetrical. It should be noted that in other embodiments of the present invention, the lengths of the ends 2a and 2c connected to the two sides of the middle portion 2b may also be unequal, and the spacing between adjacent strands of silk threads in the end parallel sections 22 of the two ends 2a and 2c may be different. That is, when the number of silk threads in each end 2a, 2c and the middle portion 2b is the same, as long as the stiffness of the middle portion 2b is greater than the stiffness of the ends 2a and 2c, it will be sufficient.

[0039] Please continue to refer to Figure 1 This embodiment also provides a spring coil comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect to the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the tumor wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0040] The spring 1 is wound with wire. The wire material of the spring 1 includes, but is not limited to: 1) metal materials including alloys, including at least one of nickel-titanium alloy, platinum-tungsten alloy, titanium-nickel-copper alloy, titanium-nickel-iron alloy, titanium-nickel-chromium alloy, copper-nickel alloy, copper-aluminum alloy, copper-zinc alloy, zinc alloy, and magnesium alloy; 2) degradable materials, such as bioresorbable / biodegradable metal or polymer materials, wherein bioresorbable / biodegradable polymer materials include, but are not limited to, at least one of polylactic acid (PLA), polyglycolic acid (PGA), polyurethane (PU), and polylactic-co-glycolic acid (PLGA / PGLA). PLA, PGA, and PGLA are preferred, making the spring 1 degradable and having a short degradation cycle and high degradation rate, which facilitates the elimination of the space-occupying effect in a relatively short period of time. In addition, the surface of the spring 1 can optionally be coated with a biomodified material, such as nylon (PA) or PLGA, by means of coating or winding, to enhance the embolic effect.

[0041] Connector 3 is a smooth, round cap structure that is fixedly connected to the distal end of spring 1, with no gap between the distal end and the spring 1. The connection methods between connector 3 and the distal end of spring 1 include, but are not limited to: 1) connector 3 is glued to the distal end of spring 1; 2) connector 3 is welded to the distal end of spring 1; 3) connector 3 is formed by hot-melting the end 2a of anti-untwisting component 2 facing connector 3, i.e., connector 3 and anti-untwisting component 2 are integrally formed; 4) connector 3 is fixed to the distal end of spring 1 by connecting to end 2a of anti-untwisting component 2. The purpose of connector 3 is to increase the smoothness of the distal end of the spring coil, thereby reducing the pushing resistance of the spring coil within the catheter or introduction sheath, and reducing the potential damage to the tumor wall caused by the spring coil when it is inserted into the tumor. In addition, it also serves to connect spring 1 to anti-untwisting component 2.

[0042] In addition, the two end portions 2a and 2c of the anti-untwisting component 2 are respectively connected to the distal end and the proximal end of the spring 1, and the connection methods between the end portions 2a and 2c of the anti-untwisting component 2 and the corresponding ends of the spring 1 include but are not limited to: 1) the end portions 2a and 2c of the anti-untwisting component 2 are connected to the corresponding ends of the spring 1 by welding; 2) the end portions 2a and 2c of the anti-untwisting component 2 are connected to the corresponding ends of the spring 1 by gluing; 3) the end portions 2a and 2c of the anti-untwisting component 2 are connected to the corresponding ends of the spring 1 by mechanical connection methods such as knotting; 4) other components such as fasteners are added between the end portions 2a and 2c of the anti-untwisting component 2 and the corresponding ends of the spring 1 to connect the end portions 2a and 2c of the anti-untwisting component 2 to the corresponding ends of the spring 1.

[0043] The anti-untwisting component 2 connects the two ends of the spring 1. On the one hand, it can play an "anti-untwisting" role, that is, preventing the spring 1 from untwisting (i.e., being straightened by external forces) during use. On the other hand, because the overall stiffness of the middle portion 2b of the anti-untwisting component 2 is greater than the overall stiffness of the end portions 2a and 2c, the anti-untwisting component 2 can make the spring coil present a "hard center and soft ends" state, thereby facilitating the internal packing of the spring 1 after it is formed into a basket and the smooth embolization process of the spring coil. Even if the distal end flips, it will not affect the smooth embolization process, thus meeting the softness requirements of different parts of the spring 1 during the embolization process. In addition, because the spring coil of this embodiment achieves the purpose of adjusting its softness solely through the anti-untwisting component 2, it is easy to implement and has low manufacturing costs.

[0044] Example 2

[0045] Please refer to Figure 2A This embodiment provides an anti-untwisting component 2 for a spring coil, the anti-untwisting component 2 having two end portions 2a, 2c and a middle portion 2b extending between the two end portions 2a, 2c. The anti-untwisting component 2 includes at least two strands of wire to form the two end portions 2a, 2c and the middle portion 2b, and the structure formed by the wire at the end portions 2a, 2c is different from the structure formed by the wire at the middle portion 2b. Each strand of wire extends from one end portion 2a of the anti-untwisting component 2 to the other end portion 2c along the axial direction of the anti-untwisting component 2, thereby making the number of wire strands in the middle portion 2b equal to the number of wire strands in each end portion 2a, 2c.

[0046] The difference between the anti-untwisting component 2 of this embodiment and the anti-untwisting component of Example 1 is that the middle part 2b includes multiple braided segments 21 and at least one intermediate parallel segment 22b, the braided segments 21 and the intermediate parallel segments 22b are arranged alternately, and the wires between adjacent braided segments 21 are parallel to each other to form the intermediate parallel segments 22b. Specifically, the end portions 2a and 2c of the anti-untwisting component 2 of this embodiment are respectively the end parallel segments 22a, and the middle portion 2b of the anti-untwisting component 2 of this embodiment is constituted by the braided segments 21 and the middle parallel segments 22b arranged alternately along the axial direction of the anti-untwisting component 2, and the braided segments 21 refer to a structure formed by winding each strand of wire together by the same braiding method or the same knotting method, that is, the winding method of each braided segment 21 is the same; the end parallel segments 22a and the middle parallel segments 22b are both structures formed by each strand of wire arranged in parallel and not entangled with each other, and the middle parallel segments 22b in the middle portion 2b can be the same (that is, the length is equal, the spacing between the wires arranged in parallel is the same, and the shape of each strand of wire is the same), or they can be not completely the same (that is, the length, the spacing between the wires arranged in parallel, and the shape of each strand of wire are the same). The braided segments 21 may be identical (i.e., the length, winding method, and arrangement structure of the braided segments in the longitudinal cross-section along the axial direction of the anti-untwisting component are the same), or may be different (i.e., the length, winding method, and arrangement structure of the braided segments in the longitudinal cross-section along the axial direction of the anti-untwisting component are different in at least one aspect). The length L2 of the end portion 2a and the length L4 of the end portion 2c (i.e., the length of the end parallel segment 22a) are both 10% to 20% of the overall length (i.e., the total length) L of the anti-untwisting component 2. The length L1' of the braided segment 21 is 3 to 4 times the length L3 of the middle parallel segment 22b, and the length of each end parallel segment 22a (i.e., the length L2 of the end portion 2a and the length L4 of the end portion 2c) are both greater than the length L3 of the middle parallel segment 22b.

[0047] In this embodiment, because the middle portion 2b is formed by alternating braided segments 21 and intermediate parallel segments 22b, its stiffness changes in a pattern of alternating between the greater stiffness corresponding to the braided segments 21 and the smaller stiffness corresponding to the intermediate parallel segments 22b. However, because the length L1' of the braided segments 21 is greater than the length L3 of the intermediate parallel segments 22b, the overall stiffness of the middle portion 2b is greater (or better) and the softness is smaller (or worse). Compared to the middle portion 2b, the end portions 2a and 2c are composed only of parallel wires and do not contain a braided segment structure, so the overall stiffness is smaller (or worse) and the softness is greater (or better). In other words, in the anti-untwisting component 2 of this embodiment, the overall stiffness of the middle portion 2b can be greater than the overall stiffness of each end portion 2a and 2c because the structure formed by all the wires of the end portions 2a and 2c is different from the structure formed by all the wires of the middle portion 2b, thereby achieving the effect of "hard in the middle and soft at both ends." In addition, in this embodiment, the lengths L2 and L4 of the end parallel sections 22a are greater than the length L3 of the middle parallel section 22b, thereby further increasing the stiffness difference between the middle portion 2b and the end portions 2a and 2c, respectively, so that the spring coil presents a more obvious "hard in the middle and soft at both ends" state.

[0048] Furthermore, the wire material of the anti-untwisting component 2 is the same as that in the first embodiment. The overall length L1 of the middle portion 2b is 60% to 80% of the overall length (i.e., total length) L of the anti-untwisting component 2. The lengths L2 of the end portions 2a and L4 of the end portions 2c (i.e., the lengths of the end parallel segments 22a) are respectively 10% to 20% of the overall length (i.e., total length) L of the anti-untwisting component 2. In this embodiment, the lengths of the end portions 2a and 2c (i.e., the lengths of the two end parallel segments 22a) on either side of the middle portion 2b are different, i.e., L2 ≠ L4. However, because the length L2 of the end parallel segments 22a is greater than the length L3 of the middle parallel segment 22b, the "hard center, soft ends" effect is still achieved. In other embodiments of the present invention, the lengths and structures of the two end portions 2a and 2c are identical, i.e., L2 = L4. As a result, the anti-untwisting component 2 as a whole has a soft end, hard center, and a generally symmetrical structure.

[0049] In addition, it should be noted that the present invention does not require that the various braided segments 21 in the middle portion 2b are completely identical, nor does it require that the various intermediate parallel segments 22b are completely identical. That is, the technical solution of the present invention allows the lengths, winding methods, and at least one aspect of the arrangement structure on the axial longitudinal section along the anti-untwisting component of the multiple braided segments 21 in the middle portion 2b to be different, so that the structures of the multiple braided segments 21 are not completely identical, and allows the lengths of the multiple intermediate parallel ends 22b, and at least one aspect of the arrangement structure on the axial longitudinal section along the axial anti-untwisting component (including the shape of each strand of wire extending along the axial direction of the anti-untwisting component 2, the arrangement layout, and the spacing between the parallel arranged wires) to be different, so that the structures of the multiple intermediate parallel segments 22b are not completely identical. Specifically, in other embodiments of the present invention, the lengths of the various braided segments 21 in the middle portion 2b may not be completely equal when using the same winding method (i.e., braiding method or knotting method); in the case of equal lengths, such as Figure 2B As shown, different winding methods (i.e., braiding or knotting methods) may be used; or different lengths and different braiding and knotting methods may be used, thereby making the structures of the multiple braided segments different by making them different in at least one of the following aspects: length, winding method, and arrangement structure in a longitudinal cross-section along the axial direction of the anti-untwisting component. Similarly, the intermediate parallel segments 22b in the intermediate portion 2b may have different lengths while having the same arrangement structure in a longitudinal cross-section (i.e., a cross-section perpendicular to the axial direction of the anti-untwisting component 2) (i.e., the arrangement layout and spacing of all filaments are the same). Alternatively, the intermediate parallel segments 22b may have the same length but different arrangement structure in a longitudinal cross-section (i.e., a cross-section perpendicular to the axial direction of the anti-untwisting component 2) (i.e., different arrangement layout and spacing of filaments), or alternatively, the intermediate parallel segments 22b may have different lengths and different longitudinal cross-sectional structures (i.e., cross-sectional structures perpendicular to the axial direction of the anti-untwisting component 2) of the parallel arrangement.

[0050] Please refer to Figure 2A and 2B This embodiment also provides a spring coil, comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the aneurysm wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0051] The connection method of the anti-untwisting component 2, spring 1 and connecting member 3 in the spring coil of this embodiment is the same as that in the first embodiment, and the materials of the anti-untwisting component 2, spring 1 and connecting member 3 are also the same as those in the first embodiment, which will not be repeated here.

[0052] The spring coil of this embodiment achieves the purpose of adjusting the softness through its anti-untwisting component 2, achieving a state of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, is easy to implement, and has low production cost.

[0053] Example 3

[0054] Please refer to Figure 3 This embodiment provides an anti-untwisting component 2 for a spring coil, the anti-untwisting component 2 having two end portions 2a, 2c and a middle portion 2b extending between the two end portions 2a, 2c. The anti-untwisting component 2 includes at least two strands of wire to form the two end portions 2a, 2c and the middle portion 2b, and the structure formed by the wire at the end portions 2a, 2c is different from the structure formed by the wire at the middle portion 2b. Each strand of wire extends from one end portion 2a of the anti-untwisting component 2 to the other end portion 2c, thereby making the number of wire strands in the middle portion 2b equal to the number of wire strands in each end portion 2a, 2c.

[0055] The anti-untwisting component 2 of this embodiment differs from the anti-untwisting component of Example 1 in that the intermediate portion 2b comprises multiple, sequentially arranged braided segments with varying structures. Specifically, the braided segments comprising the intermediate portion 2b are alternating first and second braided segments 21a, 21b, of the same length (both L1') but with different winding methods (i.e., braiding or knotting). Both the first and second braided segments 21a, 21b are formed by twisting individual strands of wire together using corresponding winding methods (i.e., braiding or knotting).

[0056] In this embodiment, because the middle portion 2b is formed by alternating the first braided segment 21a and the second braided segment 21b, the change pattern of its stiffness is that the stiffness corresponding to the first braided segment 21a and the stiffness corresponding to the second braided segment 21b change alternately. However, because the structure of the middle portion 2b is a braided structure and the structures of the end portions 2a and 2c are parallel structures, the overall stiffness of the middle portion 2b is larger (or better) and the softness is smaller (or worse), while the overall stiffness of the end portions 2a and 2c is smaller (or worse) and the softness is larger (or better) relative to the middle portion 2b. In other words, in the anti-untwisting component 2 of this embodiment, the overall stiffness of the middle portion 2b can be greater than the overall stiffness of each end portion 2a and 2c because the structure formed by all the wire materials of the end portions 2a and 2c is different from the structure formed by all the wire materials of the middle portion 2b, thereby achieving the effect of "hard in the middle and soft at both ends."

[0057] Furthermore, the wire material of the anti-untwisting component 2 is the same as that in the first embodiment. The overall length L1 of the middle portion 2b is 60% to 80% of the overall length (i.e., total length) L of the anti-untwisting component 2. The lengths of the end portions 2a and 2c are both L2 (i.e., the length of the end parallel segments 22), and L2 is 10% to 20% of the overall length (i.e., total length) L of the anti-untwisting component 2. In this embodiment, the lengths and structures of the end portions 2a and 2c connected to the middle portion 2b are identical or substantially identical. The anti-untwisting component 2 as a whole has a soft structure at both ends and a hard structure in the middle, and is generally symmetrical.

[0058] In addition, it should be noted that the present invention does not require that the braided segments in the middle portion 2b be limited to only two braided segments. It can also be n (or not less than 3) braided segments, and the n braided segments differ in at least one of their length, winding method, and arrangement structure in a longitudinal cross-section (i.e., a cross-section perpendicular to the axial direction of the anti-untwisting component 2), so that the structures of the n braided segments are not completely identical. Specifically, when the middle portion 2b is composed of n braided segments, the n braided segments can be named "braided segment 1," "braided segment 2," "braided segment 3," ..., "braided segment n" along the axial direction of the anti-untwisting component 2 and starting from a braided segment near the end 2a or 2c. Specifically, for example, while using the same winding method (i.e., braiding method or knotting method), the lengths of the n braided segments are not completely identical. Alternatively, for example, while the lengths are equal, the winding methods (i.e., braiding method or knotting method) of the n braided segments are not completely identical. Alternatively, for example, the lengths of the n braided segments are not completely identical and the winding methods (i.e., braiding method and knotting method) of the n braided segments are not completely identical. The stiffness of each braided segment is greater than that of the parallel end 22, and the stiffness of different braided segments is not identical. In some embodiments of the present invention, the middle portion 2b is composed of three or more braided segments. By designing the axial arrangement of these braided segments in the anti-untwisting component 2, the anti-untwisting component 2 can be made to have a generally axially symmetrical structure, with an overall structure that is soft at both ends and hard in the middle.

[0059] Please refer to Figure 3 This embodiment also provides a spring coil comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect to the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the tumor wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0060] The connection method of the anti-untwisting component 2, spring 1 and connecting member 3 in the spring coil of this embodiment is the same as that in the first embodiment, and the materials of the anti-untwisting component 2, spring 1 and connecting member 3 are also the same as those in the first embodiment, which will not be repeated here.

[0061] The spring coil of this embodiment achieves the purpose of adjusting the softness through its anti-untwisting component 2, achieving a state of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, is easy to implement, and has low production cost.

[0062] Example 4

[0063] Please refer to Figure 4A This embodiment provides an anti-untwisting component 2 for a spring coil, wherein the anti-untwisting component 2 has two end portions 2a, 2c and a middle portion 2b extending between the two end portions 2a, 2c.

[0064] The anti-unrotation component 2 of this embodiment is different from the anti-unrotation component of the first embodiment in that the anti-unrotation component 2 is made of cylindrical material and is cylindrical as a whole (that is, the anti-unrotation component 2 is a cylindrical structure). The outer diameter of the anti-unrotation component 2 changes along the axial direction, wherein the outer diameters of the end portions 2a and 2c are both smaller than the outer diameter of the middle portion 2b.

[0065] In this embodiment, because the outer diameter of the middle portion 2b is larger than that of the end portions 2a and 2c, the middle portion 2b has greater rigidity (or better) and less flexibility (or worse), while the end portions 2a and 2c have less rigidity (or worse) and greater flexibility (or better) than the middle portion 2b. In other words, in this embodiment, the anti-untwisting component 2 has a greater rigidity in the middle portion 2b than in the end portions 2a and 2c due to the different outer diameters of the end portions 2a and 2c and the middle portion 2b, thereby achieving the effect of "hard in the middle and soft at the ends."

[0066] Furthermore, the cylindrical material of the anti-untwisting component 2 is made of the same material as the wire material in Example 1. The length L1 of the middle portion 2b is 60% to 80% of the overall length (i.e., total length) L of the anti-untwisting component 2; the lengths L1 of the ends 2a and 2c are both 10% to 20% of the overall length (i.e., total length) L of the anti-untwisting component 2. In this embodiment, the lengths and structures of the ends 2a and 2c connected to the middle portion 2b are identical or substantially identical. The anti-untwisting component 2 has a generally symmetrical structure and is generally soft at both ends and hard in the middle. In other embodiments of the present invention, the ends 2a and 2c may have different outer diameters when the lengths are identical, or may have different outer diameters when the outer diameters are identical, or may have different outer diameters and lengths.

[0067] In addition, it should be noted that the present invention does not require that the middle portion 2b and the end portions 2a and 2c be integrally formed. The end portions 2a and 2c and the middle portion 2b may also be connected together by bonding, welding, etc. In addition, the present invention does not limit the outer diameter of the middle portion 2b to be uniform. It may also be a combination of cylindrical materials with various outer diameters, as long as the outer diameters of the end portions 2a and 2c are smaller than the smallest outer diameter of the middle portion 2b. For example, please refer to Figure 4BThe outer diameter of the middle portion 2b changes in a pattern that it gradually decreases from the middle position to the end portions 2a and 2c along the axial direction of the anti-unrotation component 2. As a result, not only can the overall stiffness of the middle portion 2b be greater than the overall stiffness of the end portions 2a and 2c, thereby achieving the effect of "hard in the middle and soft at both ends", but the middle portion 2b can also present a gradual change in stiffness, so that the overall stiffness of the anti-unrotation component 2 presents a gradual trend, which is more conducive to the smooth progress of the implantation process.

[0068] Please refer to Figure 4A and 4B This embodiment also provides a spring coil comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect to the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the tumor wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0069] The connection method of the anti-untwisting component 2, spring 1 and connecting member 3 in the spring coil of this embodiment is the same as that in the first embodiment, and the materials of the anti-untwisting component 2, spring 1 and connecting member 3 are also the same as those in the first embodiment, which will not be repeated here.

[0070] The spring coil of this embodiment achieves the purpose of adjusting the softness through its anti-untwisting component 2, achieving a state of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, is easy to implement, and has low production cost.

[0071] Example 5

[0072] Please refer to Figure 5 This embodiment provides an anti-untwisting component 2 for a spring coil. The anti-untwisting component 2 has two end portions 2a and 2c, and a middle portion 2b extending between the two end portions 2a and 2c. The anti-untwisting component 2 is made of cylindrical material and has an overall cylindrical shape, i.e., the anti-untwisting component 2 has a cylindrical structure.

[0073] The anti-untwisting component 2 of this embodiment differs from the anti-untwisting component of the fourth embodiment in that the anti-untwisting component 2 has a uniform outer diameter, the middle portion 2b is a solid cylindrical structure, and the end portions 2a and 2c are both hollow cylindrical structures.

[0074] In this embodiment, because the end portions 2a and 2c are hollow cylindrical structures and the middle portion 2b is a solid cylindrical structure, the middle portion 2b has greater overall rigidity (or better) and less flexibility (or worse), while the end portions 2a and 2c have less overall rigidity (or worse) and greater flexibility (or better) than the middle portion 2b. In other words, in this embodiment, the anti-untwisting component 2 can also achieve greater overall rigidity of the middle portion 2b than that of the end portions 2a and 2c due to the different internal structures of the cylindrical materials of the end portions 2a and 2c and the middle portion 2b, thereby achieving the effect of "hard in the middle, soft at both ends."

[0075] Furthermore, the cylindrical material of the anti-untwisting component 2 is made of the same material as the wire material in Example 1. The length L1 of the middle portion 2b is 60% to 80% of the overall length L of the anti-untwisting component 2. The lengths L2 of the ends 2a and 2c are both 10% to 20% of the overall length L of the anti-untwisting component 2. In this embodiment, the lengths and structures of the ends 2a and 2c connected to the middle portion 2b are identical or substantially identical. The anti-untwisting component 2 has a generally symmetrical structure with soft ends and a hard center.

[0076] In this embodiment, the ends 2a and 2c are both tubular structures, that is, the hollow areas of the ends 2a and 2c are cylindrical, and the inner diameters of the ends 2a and 2c are uniform. However, in the present invention, the ends 2a and 2c are not limited to tubular structures, but can be hollow cylindrical structures with hollow areas of any shape, that is, as long as the volume and shape of the hollow areas in the ends 2a and 2c are sufficient to change their rigidity, so that the overall rigidity of each end 2a and 2c can be significantly lower than that of the middle part 2b. Therefore, in other embodiments of the present invention, when the two ends 2a and 2c have the same length, the shape or inner diameter of the hollow areas of the two can be different, or, when the shape and inner diameter of the hollow areas are the same, the lengths of the two can be different, or, the shape and inner diameter of the hollow areas of the two can be different and the lengths can be different. In addition, the ends 2a and 2c can each be an axisymmetric structure so that the rigidity of each end is uniformly distributed along its own circumference.

[0077] In addition, it should be noted that the present invention does not require the middle portion 2b and the end portions 2a, 2c to be integrally formed. The end portions 2a, 2c and the middle portion 2b may also be connected together by bonding, welding, or the like.

[0078] Please refer to Figure 5This embodiment also provides a spring coil comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect to the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the tumor wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0079] The connection method of the anti-untwisting component 2, spring 1 and connecting member 3 in the spring coil of this embodiment is the same as that in the first embodiment, and the materials of the anti-untwisting component 2, spring 1 and connecting member 3 are also the same as those in the first embodiment, which will not be repeated here.

[0080] The spring coil of this embodiment achieves the purpose of adjusting the softness through its anti-untwisting component 2, achieving a state of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, is easy to implement, and has low production cost.

[0081] Example 6

[0082] Please refer to Figure 6A This embodiment provides an anti-untwisting component 2 for a spring coil, the anti-untwisting component 2 having two end portions 2a, 2c and a middle portion 2b extending between the two end portions 2a, 2c. The anti-untwisting component 2 includes at least two strands of wire to form the two end portions 2a, 2c and the middle portion 2b, and the structure formed by the wire at the end portions 2a, 2c is different from the structure formed by the wire at the middle portion 2b.

[0083] The anti-untwisting component 2 of this embodiment differs from the anti-untwisting component of the first embodiment in that at least one strand of the wire of the anti-untwisting component 2 is only located in the middle portion 2b and does not extend axially to the end portions 2a and 2c of the anti-untwisting component 2, thereby making the number of strands of the wire in the end portions 2a and 2c smaller than the number of strands of the wire in the middle portion 2b.

[0084] In this embodiment, because the number of strands of wire in the middle portion 2b is greater than the number of strands of wire in the end portions 2a and 2c, and the radial dimensions of the individual strands of wire in the end portions 2a and 2c are the same as those in the middle portion 2b, the resulting middle portion 2b has a greater overall rigidity (or better) and a lesser (or lesser) flexibility. In contrast, the resulting end portions 2a and 2c each have a lesser (or lesser) overall rigidity and a greater (or more) flexibility relative to the middle portion 2b. In other words, in this embodiment, the anti-untwisting component 2 can also achieve a greater overall rigidity in the middle portion 2b than in the individual end portions 2a and 2c because the structure formed by all the wires in the end portions 2a and 2c is different from the structure formed by all the wires in the middle portion 2b, thereby achieving the effect of "hard in the middle, soft at both ends."

[0085] In this embodiment, the lengths and structures of the ends 2a and 2c connected to the middle portion 2b are identical or substantially identical, and the anti-untwisting component 2 has a roughly symmetrical structure and is overall soft at both ends and hard in the middle.

[0086] Please refer to Figure 6A In this embodiment, there is one strand of wire in each of the end portions 2a and 2c, and four strands of wire in the middle portion 2b, and these four strands of wire are only wound together at both ends to connect with the end portions 2a and 2c. The radial dimensions of the wires in the end portions 2a and 2c are the same as the radial dimensions of each strand of wire in the middle portion 2b. However, the technical solution of the present invention is not limited thereto. In some embodiments of the present invention, when there is one strand of wire in each of the end portions 2a and 2c, and there are two or more strands of wire in the middle portion 2b, and each strand of wire in the middle portion 2b extends to the entire length L1 of the middle portion 2b along the axial direction of the anti-untwisting component 2, the middle portion 2b can be divided into at least two sections along the axial direction of the anti-untwisting component, and the number of strands of the wire in each section is the same or different, and the number of strands of the wire in the end portions 2a and 2c is less than or equal to the number of strands of the wire in each section of the middle portion 2b. The winding method, length, etc. of the wire in each section of the middle portion 2b may not be exactly the same, for example, it may be Figure 2A 、 2B as well as Figure 3 In some other embodiments of the present invention, when there is a strand of wire in each of the end portions 2a and 2c, the number of strands of wire in different regions of the middle portion 2b is not exactly the same, that is, at least one strand of wire in the middle portion 2b does not extend along the axial direction of the anti-untwisting component 2 to the entire length L1 of the middle portion 2b, as shown in FIG. Figure 6BAs shown; In some other embodiments of the present invention, there are two or more strands of wire in the end portions 2a and 2c, and the end portions 2a, 2c and the middle portion 2b can be divided into multiple sections according to the number of strands of the wire, and the maximum number of wire strands in all sections of the end portions 2a and 2c is less than the minimum number of wire strands in all sections of the middle portion 2b, and the greater the number of wire strands, the greater the stiffness, as shown in FIG. Figure 6C As shown. Furthermore, the material of the wire of the anti-untwisting component 2 in these embodiments is the same as that in the first embodiment. The overall length L1 of the middle portion 2b is 60% to 80% of the overall length (i.e., total length) L of the anti-untwisting component 2. The lengths of the end portions 2a and 2c are both L2 (i.e., the length of the end portions parallel to the end 22), and L2 is 10% to 20% of the overall length (i.e., total length) L of the anti-untwisting component 2. Of course, in other embodiments of the present invention, the lengths of the end portions 2a and 2c may be different, and the number of wire strands in the end portions 2a and 2c may also be different.

[0087] Please refer to Figures 6A-6C This embodiment also provides a spring coil comprising the anti-untwisting component 2 of this embodiment, a spring 1, and a connector 3. The spring 1 is an embolic spring coil, generally in the shape of a hollow cylinder. The connector 3 is disposed at the distal end of the spring 1. The anti-untwisting component 2 extends through the interior (or lumen) of the spring 1. The two ends 2a and 2c of the anti-untwisting component 2 connect to the proximal and distal ends of the spring 1, respectively. The distal end of the spring 1 is the end that first contacts the tumor wall, while the proximal end of the spring 1 is used for internal packing after basket formation.

[0088] The connection method of the anti-untwisting component 2, spring 1 and connecting member 3 in the spring coil of this embodiment is the same as that in the first embodiment, and the materials of the anti-untwisting component 2, spring 1 and connecting member 3 are also the same as those in the first embodiment, which will not be repeated here.

[0089] The spring coil of this embodiment achieves the purpose of adjusting the softness through its anti-untwisting component 2, achieving a state of "hard in the middle and soft at both ends", which can meet the softness requirements of different parts of the spring coil during the embolization process, is easy to implement, and has low production cost.

[0090] In addition, although Figures 6A-6CIn the anti-untwisting component shown, the middle part 2b is a braided segment, and the end parts 2a and 2b are also braided segments, but the technical solution of the present invention is not limited to this. In other embodiments of the present invention, the middle part 2b is divided into at least two sections along the axial direction of the anti-untwisting component, and the number of strands of the wire in each section of the middle part 2b is the same or different; the end parts 2a and 2c can also be divided into at least two sections along the axial direction of the anti-untwisting component, and the number of strands of the wire in each section of the end parts 2a and 2c is the same or different; and the maximum number of wire strands in each section of the end parts 2a and 2c is less than or equal to the minimum number of wire strands in each section of the middle part 2b. In addition, the end portions 2a, 2c, and the middle portion 2b may each include multiple braided segments and at least one parallel segment, or may each include multiple braided segments that are continuously arranged and have different structures, wherein in the respective regions of the end portions 2a, 2c, and the middle portion 2b, the lengths of the multiple braided segments, the number of strands of wire, the winding method, and the arrangement structure on the longitudinal cross-section (i.e., the cross-section perpendicular to the axial direction of the anti-untwisting component 2) are different, so that the structures of the multiple braided segments are not completely the same, and the lengths of the multiple parallel ends, the number of strands of wire, and the arrangement structure on the longitudinal cross-section (i.e., the cross-section perpendicular to the axial direction of the anti-untwisting component 2) (including the shape of each strand of wire extending along the axial direction of the anti-untwisting component, the arrangement layout, and the spacing between the parallelly arranged wires) are different, so that the structures of the multiple parallel segments are not completely the same.

[0091] In addition, it should be noted that the technical solutions of the present invention are not limited to the examples in the above embodiments. Those skilled in the art can arbitrarily combine the technical means in the above embodiments to derive solutions of other embodiments of the present invention. In these solutions, although the materials of the middle part and each end of the anti-untwisting component are the same, the structure of the middle part can still be made different from the structure of any one of the ends, achieving a state of "hard in the middle and soft at both ends". For example, the end of the hollow cylindrical structure in Example 5 and the middle part with the braided segment in Examples 1 to 3 are combined together to form an anti-untwisting component. The materials of the middle part and each end of the anti-untwisting component are the same, and the structure of the middle part is different from the structure of any one of the ends, which can achieve a state of "hard in the middle and soft at both ends".

[0092] Obviously, those skilled in the art may make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the invention fall within the scope of the claims and their equivalents, the invention is intended to include such modifications and variations.

Claims

1. An anti-untwisting component for a spring coil, characterized in that: The anti-unrotation component has two ends and a middle portion extending between the two ends, and the stiffness of the middle portion is greater than the stiffness of each of the end portions. The anti-unrotation component is passed through the interior of the spring of the spring coil, and the two ends of the anti-unrotation component are respectively connected to the distal end and the proximal end of the spring. The anti-unrotation component is used to prevent the spring from unrotating during use and to make the softness of the spring coil hard in the middle and soft at both ends.

2. The anti-untwisting component according to claim 1, characterized in that: The anti-untwisting component includes at least two strands of wire to form the two end portions and the middle portion, and a structure formed by the wires at the end portions is different from a structure formed by the wires at the middle portion.

3. The anti-untwisting component according to claim 2, characterized in that: The wires at the end portions are arranged in parallel with each other to form end parallel segments, and the wires at the middle portion are at least partially entangled with each other to form at least one braided segment.

4. The anti-untwisting component according to claim 3, characterized in that: The middle portion includes a plurality of braided segments and at least one middle parallel segment. The braided segments and the middle parallel segments are arranged alternately. The wires between adjacent braided segments are parallel to each other to form the middle parallel segment.

5. The anti-untwisting component according to claim 4, characterized in that: The length of the braided segment is 3 to 4 times the length of the middle parallel segment.

6. The anti-untwisting component according to claim 3, characterized in that: The middle portion includes a plurality of braided segments which are arranged continuously and have different structures.

7. The anti-untwisting component according to claim 6, characterized in that: The multiple braided segments are different in at least one of their lengths, winding methods, and arrangement structures in the longitudinal cross-section, so that the structures of the multiple braided segments are not completely the same.

8. The anti-untwisting component according to claim 2, wherein: The middle portion is divided into at least two sections along the axial direction of the anti-untwisting component, the number of strands of the wire in each section is the same or different, and the number of strands of the wire at the end portion is less than or equal to the number of strands of the wire in each section of the middle portion.

9. The anti-untwisting component according to claim 1, wherein: The anti-untwisting component is a cylindrical structure, and the outer diameter of the end portion is smaller than the outer diameter of the middle portion.

10. The anti-untwisting component according to claim 1, wherein: The anti-untwisting component is a cylindrical structure, the end portion is a hollow cylindrical structure, and the middle portion is a solid cylindrical structure.

11. The anti-untwisting component according to any one of claims 1 to 10, characterized in that: The length of the middle portion is 60% to 80% of the total length of the anti-untwisting component, and the length of each of the end portions is 10% to 20% of the total length of the anti-untwisting component.

12. The anti-untwisting component according to any one of claims 1 to 10, characterized in that: The material of the anti-untwisting component includes polymer material and / or metal material.

13. A spring coil, characterized in that: The spring coil includes a spring and the anti-unrotation component according to any one of claims 1 to 12. The anti-unrotation component is arranged inside the spring, and two ends of the anti-unrotation component are respectively connected to two ends of the spring.

14. The spring coil according to claim 13, wherein The spring coil further includes connecting pieces arranged at both ends of the spring for connecting the spring coil and the anti-untwisting component.

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