Embolic coil

Abstract

The present invention provides an embolization spring coil, comprising a spring coil body and an anti-untwisting wire arranged in the spring coil body, wherein the wire diameter of the proximal end of the anti-untwisting wire is smaller than the wire diameter of the distal end; the anti-untwisting wire comprises a curved section, wherein the proximal end of the curved section is fixedly connected to the proximal end of the spring coil body, and the distal end of the curved section is fixedly connected to the distal end of the spring coil body; or, the anti-untwisting wire comprises a curved section and a straight section, wherein the proximal end of the curved section is fixedly connected to the proximal end of the spring coil body, the distal end of the curved section is connected to the proximal end of the straight section, and the distal end of the straight section is fixedly connected to the distal end of the anti-untwisting wire. The embolization spring coil of the present invention provides a certain elongation margin for the anti-untwisting wire through the coordination of the curved section or the curved section and the straight section, and the wire diameter of the proximal end of the anti-untwisting wire becomes smaller, thereby improving the flexibility of the proximal end thereof, thereby preventing the spring coil body from being squeezed in the aneurysm cavity and elongating and hardening, and preventing the embolization spring coil from kicking the delivery catheter out of the aneurysm cavity.

Description

Technical Field

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

[0002] Intracranial aneurysm is an abnormal bulge formed by the gradual expansion of intracranial arteries under the influence of hemodynamic load or other factors. It is caused by congenital abnormalities or acquired injuries. Once an intracranial aneurysm ruptures and bleeds, the mortality and disability rates are extremely high. It is a cerebrovascular disease with high morbidity and mortality rates, and is the main cause of subarachnoid hemorrhage. The mortality rate of ruptured intracranial aneurysms is as high as 51%, and the disability rate of survivors is close to 50%.

[0003] Currently, there are two ways to treat intracranial aneurysms clinically: one is surgical craniotomy to clip or ligate the aneurysm. Its disadvantages are long operation time and great trauma to the patient. It is also very difficult to use surgical treatment for aneurysms in special parts such as the internal carotid artery and the main trunk of the vertebral basilar artery. The other is interventional endovascular treatment, which has the advantages of being minimally invasive, safe and effective. It has become the preferred clinical treatment option for many medical experts. The most commonly used method is percutaneous vascular puncture under the guidance of X-rays, and the embolic coil is embolized into the aneurysm cavity through a delivery catheter to form a solid aneurysm and seal it.

[0004] However, during the embolization process, as the length of the embolization coil filled into the aneurysm cavity becomes longer and longer, the space available for the embolization coil to fill the aneurysm cavity becomes smaller and smaller, especially in the later stage of embolization, the embolization coil is squeezed more and more severely when filled into the aneurysm cavity, which will cause the embolization coil to elongate and harden. It is easy for the embolization coil to kick the delivery catheter out of the aneurysm cavity into the parent artery, resulting in embolization failure. The tail end of the embolization coil will hang in the parent artery and cause vascular embolism. Therefore, it is necessary to remove the embolization coil and replace it with a new one and then refill it, which prolongs the operation time, increases the surgical risk and patient pain. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes an embolic coil to solve the problem that the embolic coil is easy to kick the delivery catheter out of the aneurysm cavity to the tumor-bearing artery during embolization.

[0006] In order to achieve one of the above-mentioned purposes of the invention, an embodiment of the present invention provides an embolic spring coil, comprising a spring coil body and an anti-untwisting wire disposed in the spring coil body, wherein the wire diameter of the proximal end of the anti-untwisting wire is smaller than the wire diameter of the distal end;

[0007] The anti-untwisting line includes a curved section, the proximal end of the curved section is fixedly connected to the proximal end of the spring coil body, and the distal end of the curved section is fixedly connected to the distal end of the spring coil body;

[0008] Alternatively, the anti-untwisting line includes a curved segment and a straight segment, the proximal end of the curved segment is fixedly connected to the proximal end of the spring coil body, the distal end of the curved segment is connected to the proximal end of the straight segment, and the distal end of the straight segment is fixedly connected to the distal end of the anti-untwisting line.

[0009] As a further improvement of one embodiment of the present invention, the diameter of the anti-untwisting wire gradually decreases from the distal end to the proximal end.

[0010] As a further improvement of an embodiment of the present invention, in the proximal direction of the anti-untwisting line, the line length per unit length of the proximal end of the anti-untwisting line is greater than the line length per unit length of the distal end.

[0011] As a further improvement of an embodiment of the present invention, in the distal direction of the anti-untwisting line, the line length per unit length of the anti-untwisting line gradually increases from the distal end to the proximal end.

[0012] As a further improvement of an embodiment of the present invention, the curved section is a variable pitch helix, and the pitch of the curved section gradually decreases from the distal end to the proximal end.

[0013] As a further improvement of an embodiment of the present invention, the curved section is a wave line of equal height, and the distance between adjacent wave peaks of the curved section gradually decreases from the distal end to the proximal end.

[0014] As a further improvement of an embodiment of the present invention, the anti-unwinding line is a sawtooth line with equal height, and the spacing between adjacent sawtooths of the anti-unwinding line gradually decreases from the distal end to the proximal end.

[0015] As a further improvement of one embodiment of the present invention, the length of the anti-untwisting line is 105-150% of its straight line length along the proximal and distal directions.

[0016] As a further improvement of one embodiment of the present invention, the diameter of the anti-unwinding wire is 0.02 to 0.1 mm.

[0017] As a further improvement of one embodiment of the present invention, the diameter of the anti-unwinding wire is 0.03 to 0.06 mm.

[0018] Compared with the prior art, the present invention has the following beneficial effects: the embolic spring coil of the present invention, the curved section provides a certain elongation margin for the anti-untwisting wire, during the embolization process, when the spring coil body is squeezed and elongated in the aneurysm cavity, the anti-untwisting wire can be elongated, thereby avoiding the elongation and hardening of the spring coil body, and the wire diameter of the proximal end of the anti-untwisting wire becomes smaller to improve the flexibility of the proximal end, further alleviating the hardening of the proximal end of the spring coil body during the embolization process, especially in the late stage of embolization, and the combined effect of the two can prevent the proximal end of the spring coil body from Elongation and hardening can prevent the proximal end of the embolization coil from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, thereby avoiding the proximal end of the embolization coil from being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, greatly shortening the operation time, reducing the risk of surgery, and alleviating the patient's pain; through the coordination of the curved segment and the straight segment, the elongation margin distribution of the proximal and distal ends of the anti-untwisting line can be different according to the different squeezing conditions of the distal and proximal ends of the embolization coil, thereby reducing the processing difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings provided herein are used to further illustrate the understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 It is a schematic structural diagram of a partial cutaway of the distal end portion of the embolic spring coil according to Example 1 of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the anti-unwinding line of Example 1 of the present invention;

[0022] Figure 3 This is a schematic structural diagram of the anti-unwinding line of Example 2 of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of the anti-unwinding line of Example 3 of the present invention;

[0024] Figure 5 This is a schematic diagram of the structure of the anti-unwinding line of Example 4 of the present invention;

[0025] Figure 6 This is a schematic diagram of the structure of the anti-unwinding line of Example 5 of the present invention;

[0026] Figure 7 This is a schematic structural diagram of the anti-unwinding line of Example 6 of the present invention;

[0027] Figure 8 This is a schematic diagram of the structure of the shaping device of Example 2 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of this application clearer, the technical solution of this application will be clearly and completely described in combination with the specific embodiments of this application and the corresponding drawings. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0029] In various drawings of the present invention, for the sake of convenience of illustration, some sizes of structures or parts are exaggerated relative to other structures or parts, and thus, only the basic structure of the subject matter of the present invention is illustrated.

[0030] Example 1

[0031] See also Figure 1 The present invention proposes an embolic spring coil 100, comprising a spring coil body 1 and an anti-untwisting wire 2 arranged in the spring coil body 1, the proximal end of the anti-untwisting wire 2 is fixedly connected to the proximal end of the spring coil body 1 through a first connecting portion arranged at the proximal end thereof, and the distal end of the anti-untwisting wire 2 is fixedly connected to the distal end of the spring coil body 1 through a second connecting portion arranged at the distal end thereof, that is, the two ends of the anti-untwisting wire 2 are respectively connected to the two ends of the spring coil body 1, thereby limiting the untwisting of the spring coil body 1.

[0032] In the present invention, the terms "distal" and "proximal" should be understood as viewed from the direction of the clinician, the proximal end being the end facing the clinician, and the distal end being the end away from the clinician, and the direction indicated by the arrow in the figure is from the distal end to the proximal end.

[0033] The first connection part and the second connection part of the anti-untwisting line 2 can be fixedly connected to the spring coil body 1 by welding, tying or gluing, and the glue can be medical glue such as instant glue, epoxy glue or UV glue.

[0034] The primary spiral of the coil body 1 has a diameter of 0.22-0.5 mm, so as to fill the aneurysm cavity; the coil body 1 is made of shape memory material, preferably platinum-tungsten alloy. The anti-unwinding wire 2 can be made of PP, POE, PET, nylon, etc.

[0035] It should be understood that the embolic spring coils 100, spring coil bodies 1, and anti-untwisting wires 2 described in the present invention and in the various diagrams are all in a straightened state along the proximal and distal directions, and during use and movement, they will bend synchronously with the environment and external forces.

[0036] During embolization, under the guidance of X-rays, the embolization coil 100 is delivered to the aneurysm cavity through the delivery catheter, that is, the delivery catheter is delivered to its distal end into the aneurysm cavity, and then the embolization coil 100 is pushed so that it gradually enters the aneurysm cavity from the distal end to the proximal end and fills the aneurysm cavity.

[0037] See also Figure 1 to Figure 2 In this embodiment, the anti-untwisting wire 2 includes a curved segment, the proximal end of the curved segment is fixedly connected to the proximal end of the spring coil body 1, the distal end of the curved segment is fixedly connected to the distal end of the spring coil body 1, and the wire diameter of the proximal end of the anti-untwisting wire 2 is smaller than the wire diameter of the distal end. In this way, the curved section provides a certain elongation margin for the anti-untwisting wire 2. During the embolization process, when the spring coil body 1 is squeezed and elongated in the aneurysm cavity, the anti-untwisting wire 2 can be elongated, thereby avoiding the elongation and hardening of the spring coil body 1, and the wire diameter of the proximal end of the anti-untwisting wire 2 becomes smaller, which improves the flexibility of its proximal end, further alleviating the hardening of the proximal end of the spring coil body 1 during the embolization process, especially in the late stage of embolization. The combined effect of the two can prevent the elongation and hardening of the proximal end of the spring coil body 1, thereby preventing the proximal end of the embolization spring coil 100 from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, avoiding the proximal end of the embolization spring coil 100 from being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, greatly shortening the operation time, reducing the surgical risk, and alleviating the patient's pain.

[0038] Furthermore, the wire diameter of the anti-untwisting wire 2 gradually decreases from the distal end to the proximal end, so that the flexibility of the anti-untwisting wire 2 from the distal end to the proximal end can be improved. In this way, the flexibility of the embolization spring coil 100 can be improved in a targeted manner according to the different degrees of compression of the embolization spring coil 100 from the distal end to the proximal end, and the hardness of the embolization spring coil 100 can be reduced step by step from the distal end to the proximal end, especially the hardness of the proximal end of the embolization spring coil 100 can be significantly reduced, so as to solve the problem that the hardness of the spring coil body 1 gradually increases from the distal end to the proximal end due to the increasingly severe compression of the embolization spring coil 100 caused by the increasingly smaller space in the aneurysm cavity during the embolization process, thereby preventing the embolization spring coil 100 from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, and avoiding the proximal end of the embolization spring coil 100 from being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, thereby greatly shortening the operation time, reducing the operation risk, and alleviating the patient's pain.

[0039] It can be understood that the diameter of the anti-untwisting line 2 described here gradually decreases from the distal end to the proximal end. The diameter of the anti-untwisting line 2 can be continuously reduced from the distal end to the proximal end, or the diameter of the anti-untwisting line 2 can be reduced in a step-like manner from the distal end to the proximal end, or the diameter of the anti-untwisting line 2 can be reduced in stages from the distal end to the proximal end or in other ways, as long as it can achieve better and better flexibility of the anti-untwisting line 2 from the distal end to the proximal end.

[0040] Furthermore, in the proximal and distal directions of the anti-untwisting wire 2, which is the direction from the distal end to the proximal end of the anti-untwisting wire 2, the length of the proximal end of the anti-untwisting wire 2 per unit length is greater than the length of the distal end per unit length. Thus, the anti-untwisting wire 2 not only has an elongation margin, but also greatly increases the elongation of its proximal end, thereby alleviating the hardening of the proximal end of the coil body 1 due to elongation during the embolization process, especially in the late stage of embolization, thereby preventing the proximal end of the embolization coil 100 from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, thereby avoiding the proximal end of the embolization coil 100 from being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, thereby greatly shortening the operation time, reducing the operation risk, and alleviating the patient's pain.

[0041] Preferably, in the proximal and distal directions of the anti-untwisting wire 2, the length of the anti-untwisting wire 2 per unit length gradually increases from the distal end to the proximal end, that is, the elongation amount of the anti-untwisting wire 2 from the distal end to the proximal end becomes larger and larger, so that the elongation margin of the spring coil body 1 becomes larger and larger from the distal end to the proximal end. During the embolization process, when the spring coil body 1 is elongated due to different degrees of compression in the aneurysm cavity, the distal and proximal ends of the anti-untwisting wire 2 can provide sufficient elongation margins accordingly, especially for the situation that the elongation margin required for the proximal end of the anti-untwisting wire 2 is greater than the elongation margin required for the distal end, which significantly increases the embolization efficiency. By increasing the elongation of the proximal end of the embolization coil 100, the problem of the embolization coil 100 being squeezed more and more severely during the embolization process, which causes the coil body 1 to straighten from the distal end to the proximal end and gradually harden, is solved. This prevents the embolization coil 100 from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, and avoids the proximal end of the embolization coil 100 being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, thereby greatly shortening the operation time, reducing the operation risk, and alleviating the patient's pain.

[0042] Furthermore, the length of the anti-untwisting wire 2 is 105-150% of its straight length in the proximal and distal directions, which not only allows the anti-untwisting wire 2 to be stretched, especially the stretchable amount of the anti-untwisting wire 2 gradually increases from the distal end to the proximal end within this range, which can prevent the spring coil body 1 from being straightened and the hardness increased due to the length limitation of the anti-untwisting wire 2 during the embolization process, thereby causing the remaining part of the embolization spring coil 100 to be unable to be delivered into the aneurysm, and the tail end of the embolization spring coil 100 hanging in the tumor-bearing artery to cause vascular embolism, and can also prevent the spring coil body 1 from untwisting during the embolization process.

[0043] Furthermore, the wire diameter of the anti-untwisting wire 2 is 0.02-0.1 mm, preferably, the wire diameter of the anti-untwisting wire 2 is 0.03-0.06 mm, which can prevent the coil body 1 from untwisting during the embolization process on the one hand, and ensure that the anti-untwisting wire 2 has a certain flexibility on the other hand. In particular, the wire diameter of the anti-untwisting wire 2 gradually decreases from the distal end to the proximal end within this range, which can prevent the embolization coil 100 from kicking the delivery catheter out of the aneurysm entrance into the tumor-bearing artery, thereby causing the remaining part of the embolization coil 100 to be unable to be delivered into the aneurysm, the tail end of the embolization coil 100 hanging in the tumor-bearing artery, and causing vascular embolism.

[0044] See also Figure 2 Specifically, in this embodiment, the curved section is configured as a spiral line, and the pitch is 0.2 to 1 mm.

[0045] Preferably, the helical wire is of variable pitch, and the pitch of the curved section gradually decreases from the distal end to the proximal end, that is, the density of the helical coil of the curved section gradually increases from the distal end to the proximal end, that is, the elongation amount of the anti-untwisting wire 2 from the distal end to the proximal end gradually increases, so that the elongation margin of the spring coil body 1 becomes larger and larger from the distal end to the proximal end. During the embolization process, when the spring coil body 1 is elongated due to different degrees of compression in the aneurysm cavity, the anti-untwisting wire 2 can provide sufficient elongation margin correspondingly at different positions from the distal end to the proximal end, thereby specifically improving the problem that the embolization spring coil 100 is squeezed more and more seriously due to the increasing length of the embolization spring coil 100 entering the aneurysm cavity, thereby causing the hardness of the spring coil body 1 to gradually increase from the distal end to the proximal end, thereby preventing the embolization spring coil 100 from kicking the delivery catheter out of the aneurysm cavity entrance to the tumor-bearing artery.

[0046] The spiral line of the curved section can be set to have a constant diameter to adapt to the size of the spring coil body 1 and reduce the difficulty of processing.

[0047] Preferably, the curved section is configured to be variable in diameter, so that the spiral diameter of the curved section gradually increases from the distal end to the proximal end, thereby further increasing the elongation margin of the embolic spring coil 100 .

[0048] During processing, the curved section can be wound on a rod and heat-set to prepare a spiral line, the setting temperature is 80-130°C, the setting time is 15-120 minutes, the pitch of the curved section can be controlled to gradually decrease from the distal end to the proximal end by the density of the winding, and the thread diameter of the anti-unwinding line 2 can be further controlled by selecting the diameter of the rod. For example, by selecting the rod to gradually increase the diameter, the thread diameter of the curved section can be gradually increased from the proximal end to the distal end. Of course, other shaping methods can also be used to process the curved section, as long as the shape and size of the curved section can meet the requirements.

[0049] Example 2

[0050] Please refer to Figure 3 As shown, another embodiment of the present invention is shown, and the difference between this embodiment 2 and embodiment 1 is that:

[0051] The curved section is set as a wavy line with an amplitude of 0.05 to 1 mm, and the spacing between adjacent wave peaks of the curved section gradually decreases from the distal end to the proximal end, that is, the wave peak density of the curved section gradually increases from the distal end to the proximal end, so that the elongation amount of the anti-untwisting line 2 gradually increases from the distal end to the proximal end, so that the elongation margin of the spring coil body 1 becomes larger and larger from the distal end to the proximal end. During the embolization process, when the spring coil body 1 is elongated due to different degrees of compression in the aneurysm cavity, the anti-untwisting line 2 can provide sufficient elongation margins at different positions from the distal end to the proximal end, which can specifically improve the problem of the gradual increase in hardness of the spring coil body 1 from the distal end to the proximal end due to the increasing length of the embolization spring coil 100 entering the aneurysm cavity, which makes the embolization spring coil 100 more and more severely squeezed, thereby preventing the embolization spring coil 100 from kicking the delivery catheter out of the aneurysm entrance to the tumor-bearing artery.

[0052] In this embodiment, the wavy lines of the curved section are set to be of the same height to adapt to the size of the spring coil body 1 and reduce the difficulty of processing; in other embodiments, the wavy lines of the curved section can also be set to have an amplitude that gradually increases from the distal end to the proximal end to further increase the elongation margin of the embolic spring coil 100.

[0053] During processing, the anti-unwinding line 2 can be placed Figure 8 The shaping device 200 shown in the figure performs heat shaping so as to prepare the curved section into a wavy line, wherein the shaping temperature is 80-130°C and the shaping time is 15-120 minutes. The curved shape of the curved section can be controlled by selecting the corrugation shape of the shaping device 200, and the spacing between adjacent wave peaks of the curved section can be controlled to gradually decrease from the distal end to the proximal end by selecting the corrugation density of the shaping device 200. The spacing between adjacent wave peaks of the curved section can also be controlled to gradually decrease from the distal end to the proximal end by selecting the corrugation height of the shaping device 200. Figure 3 The anti-untwisting line 2 shown is prepared by using a shaping device 200 whose corrugation density gradually increases from one end to the other end.

[0054] Except for the above differences, the other aspects of Example 2 are the same as those of Example 1, and will not be described in detail here.

[0055] Example 3

[0056] Please refer to Figure 4 As shown, another embodiment of the present invention is shown. The difference between the embodiment 3 and the embodiment 2 is that:

[0057] The curved section is set as a sawtooth line with a sawtooth height of 0.05 to 1 mm, and the spacing between adjacent sawtooths of the anti-untwisting line 2 gradually decreases from the distal end to the proximal end, that is, the sawtooth density of the anti-untwisting line 2 gradually increases from the distal end to the proximal end, so that the elongation amount of the anti-untwisting line 2 gradually increases from the distal end to the proximal end, so that the elongation margin of the spring coil body 1 becomes larger and larger from the distal end to the proximal end. During the embolization process, when the spring coil body 1 is elongated due to different degrees of compression in the aneurysm cavity, the anti-untwisting line 2 can provide sufficient elongation margin correspondingly at different positions from the distal end to the proximal end, which can specifically improve the problem of the gradual increase in the hardness of the spring coil body 1 from the distal end to the proximal end due to the increasing length of the embolization spring coil 100 entering the aneurysm cavity, which makes the embolization spring coil 100 more and more severely squeezed, thereby preventing the embolization spring coil 100 from kicking the delivery catheter out of the aneurysm cavity entrance to the tumor-bearing artery.

[0058] In this embodiment, the serrations of the curved section are set to be of equal height to match the size of the spring coil body 1 and reduce the difficulty of processing; in other embodiments, the serrations of the curved section can also be set to gradually increase the serration height from the distal end to the proximal end to further increase the elongation margin of the embolic spring coil 100.

[0059] During processing, the sawtooth shape of the shaping device 200 can be selected to control the bending shape of the bending section, the sawtooth density of the shaping device 200 can be selected to control the spacing between adjacent sawteeth of the bending section to gradually decrease from the distal end to the proximal end, and the sawtooth height of the shaping device 200 can be selected to control the spacing between adjacent sawteeth of the bending section to gradually decrease from the distal end to the proximal end.

[0060] Except for the above differences, the other aspects of Example 3 are the same as those of Example 2, and will not be described in detail here.

[0061] Example 4

[0062] Please refer to Figure 5 As shown, it is another embodiment of the present invention. The difference between this embodiment 4 and embodiment 1 is that:

[0063] The anti-untwisting wire 2 includes a curved segment and a straight segment, the proximal end of the curved segment is fixedly connected to the proximal end of the coil body 1, the distal end of the curved segment is connected to the proximal end of the straight segment, and the distal end of the straight segment is fixedly connected to the distal end of the anti-untwisting wire 2. In this way, not only can the processing difficulty be reduced, but also the different requirements for the elongation of the distal and proximal ends of the anti-untwisting wire 2 can be met, and the proximal end of the embolization coil 100 is prevented from kicking the delivery catheter out of the aneurysm entrance to the tumor-bearing artery, thereby preventing the remaining part of the embolization coil 100 from being delivered into the aneurysm, and the tail end of the embolization coil 100 hanging in the tumor-bearing artery, resulting in vascular embolism.

[0064] In this embodiment, the structure of the bending section is the same as that of Embodiment 1, and will not be described in detail here.

[0065] Except for the above differences, the fourth embodiment is the same as the first embodiment, and will not be described in detail here.

[0066] Example 5

[0067] Please refer to Figure 6 As shown, it is another embodiment of the present invention. The difference between this embodiment 5 and embodiment 2 is that:

[0068] The anti-untwisting wire 2 includes a curved segment and a straight segment, the proximal end of the curved segment is fixedly connected to the proximal end of the coil body 1, the distal end of the curved segment is connected to the proximal end of the straight segment, and the distal end of the straight segment is fixedly connected to the distal end of the anti-untwisting wire 2. In this way, not only can the processing difficulty be reduced, but also the different requirements for the elongation of the distal and proximal ends of the anti-untwisting wire 2 can be met, and the proximal end of the embolization coil 100 is prevented from kicking the delivery catheter out of the aneurysm entrance to the tumor-bearing artery, thereby preventing the remaining part of the embolization coil 100 from being delivered into the aneurysm, and the tail end of the embolization coil 100 hanging in the tumor-bearing artery, resulting in vascular embolism.

[0069] In this embodiment, the structure of the bending section is the same as that of Embodiment 2, and will not be described in detail here.

[0070] Except for the above differences, the other aspects of Example 4 are the same as those of Example 2, and will not be described in detail here.

[0071] Example 6

[0072] Please refer to Figure 7 As shown, it is another embodiment of the present invention. The difference between this embodiment 6 and embodiment 3 is that:

[0073] The anti-untwisting wire 2 includes a curved segment and a straight segment, the proximal end of the curved segment is fixedly connected to the proximal end of the coil body 1, the distal end of the curved segment is connected to the proximal end of the straight segment, and the distal end of the straight segment is fixedly connected to the distal end of the anti-untwisting wire 2. In this way, not only can the processing difficulty be reduced, but also the different requirements for the elongation of the distal and proximal ends of the anti-untwisting wire 2 can be met, and the proximal end of the embolization coil 100 is prevented from kicking the delivery catheter out of the aneurysm entrance to the tumor-bearing artery, thereby preventing the remaining part of the embolization coil 100 from being delivered into the aneurysm, and the tail end of the embolization coil 100 hanging in the tumor-bearing artery, resulting in vascular embolism.

[0074] In this embodiment, the structure of the bending section is the same as that of Embodiment 3, and will not be described in detail here.

[0075] Except for the above differences, the other aspects of Example 6 are the same as Example 3, which will not be described in detail here.

[0076] In summary, the embolization coil 100 proposed in the present invention, the curved section provides a certain elongation margin for the anti-unwinding wire 2. During the embolization process, when the coil body 1 is squeezed and stretched in the aneurysm cavity, the anti-unwinding wire 2 can be stretched, thereby avoiding the elongation and hardening of the coil body 1, and the wire diameter of the proximal end of the anti-unwinding wire 2 is reduced to improve the flexibility of its proximal end, further alleviating the hardening of the proximal end of the coil body 1 during the embolization process, especially in the late stage of embolization. The combined effect of the two can prevent the elongation and hardening of the proximal end of the coil body 1, thereby preventing the proximal end of the embolization coil 100 from kicking the delivery catheter out of the aneurysm cavity into the tumor-bearing artery, and avoiding the proximal end of the embolization coil 100 from being unable to be delivered into the aneurysm cavity and causing its tail end to hang in the tumor-bearing artery to cause vascular embolism, greatly reducing The operation time is shortened, the operation risk is reduced, and the patient's pain is alleviated; further, the coordination of the curved segment and the straight segment, the gradually decreasing diameter of the anti-untwisting wire 2 from the distal end to the proximal end, the proximal unit length of the anti-untwisting wire 2 in the proximal and distal directions of the anti-untwisting wire 2 is greater than the distal unit length, and the unit length of the anti-untwisting wire 2 gradually increases from the distal end to the proximal end, all of which can make the flexibility of the anti-untwisting wire 2 from the distal end to the proximal end better or increase the elongation, thereby meeting the different requirements of the distal and proximal ends of the anti-untwisting wire 2 for its elongation, and preventing the proximal end of the embolization coil 100 from kicking the delivery catheter out of the aneurysm entrance to the tumor-bearing artery, thereby preventing the remaining part of the embolization coil 100 from being delivered into the aneurysm, and the tail end of the embolization coil 100 hanging in the tumor-bearing artery, causing vascular embolism.

[0077] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0078] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all fall within the protection scope of the present invention.

Claims

1. An embolic coil, characterized in that: It comprises a spring coil body and an anti-untwisting wire arranged in the spring coil body, wherein the wire diameter of the proximal end of the anti-untwisting wire is smaller than the wire diameter of the distal end, and in the proximal and distal directions of the anti-untwisting wire, the wire length per unit length of the anti-untwisting wire gradually increases from the distal end to the proximal end; The anti-untwisting line includes a curved section, the proximal end of the curved section is fixedly connected to the proximal end of the spring coil body, and the distal end of the curved section is fixedly connected to the distal end of the spring coil body; Alternatively, the anti-untwisting line includes a curved segment and a straight segment, the proximal end of the curved segment is fixedly connected to the proximal end of the spring coil body, the distal end of the curved segment is connected to the proximal end of the straight segment, and the distal end of the straight segment is fixedly connected to the distal end of the anti-untwisting line.

2. The embolic coil according to claim 1, characterized in that: The diameter of the anti-untwisting line gradually decreases from the distal end to the proximal end.

3. The embolic coil according to any one of claims 1 to 2, characterized in that: The curved section is a variable pitch helix, and the pitch of the curved section gradually decreases from the distal end to the proximal end.

4. The embolic coil according to any one of claims 1 to 2, characterized in that: The curved section is a wave line of equal height, and the distance between adjacent wave crests of the curved section gradually decreases from the far end to the near end.

5. The embolic coil according to any one of claims 1 to 2, characterized in that: The anti-unwinding line is a sawtooth line with equal height, and the spacing between adjacent sawtooths of the anti-unwinding line gradually decreases from the distal end to the proximal end.

6. The embolic coil according to claim 1, characterized in that: The length of the anti-untwisting line is 105-150% of its straight line length along the proximal and distal directions.

7. The embolic coil according to claim 1, characterized in that: The anti-unwinding wire has a wire diameter of 0.02 to 0.1 mm.

8. The embolic coil according to claim 7, characterized in that: The anti-unwinding wire has a wire diameter of 0.03 to 0.06 mm.

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