Embolism system based on wide-neck aneurysm

Abstract

The invention relates to an embolism system based on wide-neck aneurysm, and the embolism system comprises an embolism part which is made of shape memory polymer foam, and the embolism part sequentially comprises a compressed loading state, a limited expansion implantation state and a complete expansion preset state according to the relative volume from small to large; the anchoring arm is arranged in the embolism part in a penetrating mode, when the embolism part is in a preset state, the anchoring arm is embedded in the embolism part, and when the embolism part is in an implanted state, the end of the anchoring arm is exposed out of the embolism part and used for being anchored to the inner wall of the wide-neck aneurysm; the intervention catheter is used for accommodating the embolism piece in a loaded state; the delivery tube is arranged in the interventional catheter in a sliding and penetrating mode, the delivery tube and the embolism part have an opposite connecting state and an opposite releasing state, in the connecting state, the embolism part is located on the far end side of the exterior of the delivery tube, and in the releasing state, the embolism part is allowed to be separated from the delivery tube so as to be released into the wide-neck aneurysm.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vascular intervention treatment, in particular to an embolization system based on wide-necked aneurysm. BACKGROUND

[0002] In the field of clinical intervention of vascular diseases, the vascular embolization device made of high polymer material has shown important application value. With the development of minimally invasive treatment technology, shape memory polymer (SMP) can significantly reduce treatment trauma and reduce the incidence of postoperative complications due to its convenience of delivery through catheter and the characteristics of self-expansion in vivo, and has shown advantages in the treatment of various vascular diseases.

[0003] At present, such embolization devices are mainly polyurethane shape memory polymer foams, and the shape memory performance is mainly realized by monomer combination design and preparation process control. The synthesis of typical polyurethane SMP foam takes N,N,N',N'-tetra(2-hydroxypropyl)ethylenediamine (HPED), triethanolamine (TEA) and hexamethylene diisocyanate (HDI) as basic raw materials, and in some technical solutions, trimethylhexamethylene diisocyanate (TMHDI) is also introduced to control the hydrophobicity of the material to adapt to the expansion requirements in different in vivo environments.

[0004] Wide-necked aneurysm has a large opening size and a special aneurysm cavity structure, which puts high requirements on the fixation stability of the embolization device. However, the current conventional embolization devices, including polyurethane SMP foam, are prone to falling off and displacement in the wide-necked aneurysm cavity. Therefore, in view of the structural characteristics of wide-necked aneurysm, it is an urgent technical requirement to develop a high polymer vascular embolization device that is fixed and stable and not easy to fall off. SUMMARY

[0005] The present application provides a vascular embolization system for wide-necked aneurysm, which is more convenient to position and release, in order to overcome the position deviation problem of embolization device in wide-necked aneurysm at the initial release stage and after implantation.

[0006] The present application provides a vascular embolization system for wide-necked aneurysm, which is more convenient to position and release, in order to overcome the position deviation problem of embolization device in wide-necked aneurysm at the initial release stage and after implantation. The embolization device is made of shape memory polymer foam, and the embolization device comprises, in order from small to large relative volume, a compressed loading state, a restricted expansion implantation state and a fully expanded preset state. The anchor arm is arranged in the embolization device, and in the preset state, the anchor arm is embedded in the interior of the embolization device, and in the implantation state, the end of the anchor arm is exposed outside the embolization device for anchoring to the inner wall of the wide-necked aneurysm. The interventional catheter is used to accommodate the embolization device in the loading state. A delivery tube is slidably inserted within the interventional catheter, and the delivery tube has a relative connected state and a disengaged state with respect to the embolic element. In the connected state, the embolic element is located on the distal side outside the delivery tube, and in the disengaged state, the embolic element is allowed to detach from the delivery tube to be released into the wide carotid aneurysm.

[0007] This application also provides an embolization component based on a wide-necked aneurysm, comprising: The embolization device is made of shape memory polymer foam. The embolization device includes, in order of increasing relative volume, a compressed loading state, a restricted expansion implantation state, and a fully expanded preset state. An anchoring arm is inserted into the embolization member, wherein in a preset state, the anchoring arm is embedded inside the embolization member; in an implanted state, the end of the anchoring arm is exposed outside the embolization member for anchoring to the inner wall of the wide carotid aneurysm; and in a loaded state, the anchoring arm is abutted against the outer periphery of the distal segment.

[0008] Several alternative methods are provided below, but they are not intended as additional limitations on the overall solution above. They are merely further additions or optimizations. Provided there are no technical or logical contradictions, each alternative method can be combined individually with respect to the overall solution above, or multiple alternative methods can be combined with each other.

[0009] Optionally, the plug has a circumferentially arranged circumferential cut, and a retaining ring is embedded in the circumferential cut. In the plug, the part surrounded by the circumferential cut is clamped and fixed by the retaining ring. One end of the anchoring arm is fixed to the retaining ring, and the other end extends radially outward. In a preset state, the anchoring arm of the plug is embedded in the circumferential cut.

[0010] Optionally, the number of anchoring arms is three to eight, which are radially distributed around the outer periphery of the bundle ring. Each anchoring arm is straight, S-shaped, or self-circulated in a ring when unfolded.

[0011] Optionally, the plug is axially divided into a distal section and a proximal section by the ferrule, and in the loaded state, each of the anchoring arms is brought together against the outer periphery of the distal section.

[0012] Optionally, the embolization element is spherical and has a spatial axis, and the distal segment has a core wire extending along the axis fixed inside by pre-embedding or threading after molding. The core wire also serves as a radiopaque marker.

[0013] Optionally, the proximal segment is provided with an elastic wire, one end of which is integrally connected to the core wire or separately fixedly connected, and the other end of which is connected to a first sphere; The delivery tube is provided with a pull wire, the proximal end of which is the operating end, and the distal end of which is provided with a second ball. When the delivery tube and the embolization are connected, the first ball is placed in the delivery tube and is located near the proximal end of the second ball. The first ball is blocked by the second ball and remains in the delivery tube. With the delivery tube and the plug in the detached state, the first ball passes over the second ball to allow disengagement from the delivery tube.

[0014] Optionally, the elastic wire has an initial state of spiral winding and a straightened state after being stressed. In the straightened state, the first ball extends to the outside of the plug. The proximal segment has a receiving groove inside, and the receiving groove has an opening facing the proximal end. In the initial state, the elastic wire pulls the first ball into the receiving groove. In the preset state and the implanted state, the opening of the receiving groove is closed by the embolization member itself.

[0015] Optionally, the distal end of the delivery tube has a reduced diameter section, and in the connected state, both the first ball and the second ball are located within the reduced diameter section; The diameter of the reduced-diameter section is smaller than the sum of the diameters of the first sphere and the second sphere. In the connected state, the first sphere is restrained by the reduced-diameter section and moves to the distal end past the second sphere. In the unloaded state, the pull wire pulls the second sphere to the proximal end relative to the delivery tube, causing the first sphere and the second sphere to move to the proximal end side out of the reduced-diameter section. In the delivery tube, the diameter of the portion located near the reduced diameter section is greater than or equal to the sum of the diameters of the first sphere and the second sphere, which is used to release the restraint and allow the first sphere to pass over the second sphere to the distal end.

[0016] Optionally, the distal portion of the delivery tube is a straight tube as a whole, and a release hole is provided on the tube wall; The diameter of the delivery tube is smaller than the sum of the diameters of the first sphere and the second sphere. In the connected state, the delivery tube restricts the first sphere from passing over the second sphere at the distal end. In the released state, the pull wire pulls the second ball proximally relative to the delivery tube, causing the first ball and the second ball to move proximally until at least one of the first ball and the second ball partially enters the release hole, allowing the first ball to be transferred from the proximal side of the second ball to the distal side of the second ball.

[0017] Optionally, the release hole is a strip-shaped hole that extends spirally around the axis of the delivery tube and has a relative length and width, wherein the width of the release hole is smaller than the diameter of the first sphere and the second sphere, so as to restrict the first sphere and the second sphere from exiting the release hole.

[0018] This application improves the structure of the embolization device, achieving a better positioning and implantation effect within a wide-necked aneurysm, while also ensuring filling effect and safety. Furthermore, by combining it with the delivery tube, accurate control of the timing of release can be achieved. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram showing the displacement of the embolization device within the aneurysm in the prior art; Figure 2 This is a schematic diagram illustrating the change in the relative position of the plug component with respect to the end of the anchoring arm under different states in one embodiment of this application; Figure 3 This is a schematic diagram of the structure of the clamping ring and the anchoring arm in one embodiment of this application; Figure 4 This is a schematic diagram of the structure of the clamping ring and the anchoring arm in another embodiment of this application; Figure 5 This is a schematic diagram of the structure of the clamping ring and the anchoring arm in another embodiment of this application; Figure 6 This is a schematic diagram of the plug component in a loaded state according to one embodiment of this application; Figure 7 This is a schematic diagram of the processing of the embolization component in one embodiment of this application; Figure 8 This is a schematic diagram of an embolization system according to an embodiment of this application being used for intervention within a wide-necked aneurysm; Figure 9 This is a schematic diagram of another interventional route into a wide-necked aneurysm according to this application; Figure 10 for Figure 8 A schematic diagram of the distal section of the embolized component after expansion; Figure 11 for Figure 10 A schematic diagram showing the release of the embolized component after the end section expands. Figure 12 This is a diagram showing the embolization device located within the wide-necked aneurysm after the embolization is completed. Figure 13 This is a schematic diagram showing the connection between the embolization element and the delivery tube in the interventional catheter in one embodiment of this application; Figure 14 middle Figure 13 A schematic diagram showing the embolized component and delivery tube in a disengaged state; Figure 15 This is a schematic cross-sectional view of the delivery tube at the release hole in one embodiment of this application; Figure 16 for Figure 15 The unfolded diagram of the delivery tube at the release hole.

[0021] The component labels are as follows: 100. Blood vessel; 110. Hemangioma; 111. Opening site; 200, Plug; 201, Circumferential cut; 202, Axial hole; 203, Reception groove; 204, Distal section; 205, Proximal section; 210, Binding ring; 220, Anchoring arm; 221, Third imaging marker; 230, Core wire; 240, Elastic wire; 250, First sphere; 300. Delivery tube; 301. Release hole; 302. Second developing mark; 310. Pull wire; 320. Second sphere; 330. Reduction section; 400. Interventional catheter; 401. First contrast marker. Detailed Implementation

[0022] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0023] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0026] See Figure 1 For the treatment of hemangioma 110, polyurethane SMP foam can be used as the embolization element 200. It is generally pre-compressed and loaded into the interventional catheter and delivered in the body through the interventional catheter along the blood vessel 100. After reaching the predetermined implantation position, the embolization element 200 is pushed out of the distal end of the interventional catheter and exposed in the lumen of the hemangioma 110. Taking a wide-necked hemangioma as an example, its opening 111 is relatively large. The embolization element 200 may be dislodged from the opening 111 under the action of blood flow, deviating from the preset implantation position and causing safety hazards.

[0027] To address the issues of positioning and controlled release of embolization components within wide-necked aneurysms, one embodiment of this application provides an embolization system for wide-necked aneurysms, having a relative distal and proximal end. The proximal end generally refers to the side adjacent to the operator (e.g., a physician), while the distal end is the side relatively far away. Along the interventional path, each component itself has a relative distal and proximal end. When the proximal and distal ends are in a straight line, the axial direction is also defined, and correspondingly, the radial direction perpendicular to the axial direction and the circumferential direction arranged around the axial direction are also defined. When used to refer to a structure, "end" in this text indicates the endpoint of the structure, or a point or region in that lateral direction, or a specific structure connected to that point or region.

[0028] See Figures 2-8 The embolization system of this embodiment includes an embolization component 200, an anchoring arm 220, an interventional catheter 400, and a delivery tube 300. Based on the implant, it can be understood that an embodiment of this application also provides an embolization component based on a wide-necked aneurysm, including an embolization component 200 and an anchoring arm 220 connected to the embolization component 200. Both remain in the body after implantation, while the interventional catheter 400 and the delivery tube 300 serve as interventional delivery devices.

[0029] The embolization component 200 is block-shaped, and its overall shape is not strictly limited. It can be adapted to the physiological structure of the site to be embolized. For example, after full expansion, it can be cylindrical, frustum-shaped, spherical, ellipsoidal, or even various irregular shapes. Combined with the common shape of wide carotid aneurysms, it can be crown-shaped, for example. The embolization component 200 itself is made of shape memory polymer foam. Its material and preparation can be implemented using existing technologies, such as polyurethane memory foam. At relatively low temperatures, it can maintain its current molded shape and expand to a preset state when exposed to water and / or affected by body temperature. For example, based on the polyurethane shape memory foam disclosed in Chinese patent document CN120550217A, a polyurethane acrylate prepolymer can be prepared using macromolecular polyols, diisocyanates, chain extenders containing disulfide bonds, other small molecule chain extenders, and acrylate end-capping agents. Then, the polyurethane acrylate prepolymer, acrylate monomer diluent, foaming agent, foaming aid, photoinitiator, and high-boiling-point solvent are mixed evenly to form a foaming liquid. The foaming liquid is then subjected to photocuring and foaming in sequence to obtain a solid foam with an expansion rate of 100 to 150 times.

[0030] The interventional catheter 400 is used to accommodate the embolization component 200 in its loaded state. The interventional catheter 400 can be made of existing materials and is suitable for interventional delivery. The inner wall of the interventional catheter 400 may have a lubricating layer. An operating handle may be provided at the proximal end of the interventional catheter 400 as needed. The interventional catheter 400 may also be configured with a bending mechanism to adapt to complex and tortuous access paths. The distal end of the interventional catheter 400 can be changed by a corresponding drive mechanism on the operating handle. The distal end of the interventional catheter 400 may be provided with an annular first imaging mark 401.

[0031] The embolic component 200 has a porous internal structure, allowing its volume to be changed through compression to suit loading and transcatheter delivery. It expands within the body and occupies space at the implantation site, achieving an embolic effect. During use, it generally includes components in ascending order of relative volume in common configurations: The compressed loading state, for example, is contained within the interventional catheter 400 for interventional delivery; In the case of a restricted expansion implantation state, taking the aneurysm located inside a wide-necked aneurysm as an example, the restricted expansion can be understood as being slightly compressed by the surrounding tissues. Because it has a tendency to expand further, there is an interaction force between it and the surrounding tissues, which keeps it taut at the implantation site. The fully expanded preset state can be understood as the maximum volume that the plug 200 can expand to when there is no compressive force around it.

[0032] In terms of volume, the preset state can be 50 to 100 times the size of the loaded state. In some cases, the axial length of the plug remains basically unchanged in the preset state and the loaded state, only expanding radially outward, and the outer diameter can be expanded to about 10 times.

[0033] See Figure 2 To address the positioning of the embolization component 200, an anchoring arm 220 is also provided in this embodiment. The anchoring arm 220 is inserted into the embolization component 200. In the preset state, the anchoring arm 220 is embedded inside the embolization component 200. When the embolization component 200 is implanted, it is subjected to pressure from the surrounding tissue, and its foam material will deform and compress. However, the end of the anchoring arm 220 will remain in contact with the surrounding tissue for positioning. That is, the end will be exposed on the outer peripheral surface of the embolization component 200 and anchored to the inner wall of the wide carotid aneurysm. Here, the exposed length of the end of the anchoring arm 220 is not strictly limited. It is only emphasized that it is in contact with the surrounding tissue. Or it can be understood as the end of the anchoring arm 220 will extend further outward relative to the compression deformation of the embolization component 200 itself, thereby achieving positional anchoring by changing the local shape of the surrounding tissue.

[0034] See Figures 3-5 The anchoring arms 220 can be made of shape-memory metal materials, such as nickel-titanium alloy wire, and are pre-treated to obtain a shape corresponding to the extended state, tending to extend upon release within the body. There are three to eight anchoring arms 220, radially distributed around the outer periphery of the binding ring 210. In different embodiments, the anchoring arms 220 can also be configured with different shapes. Each anchoring arm 220 is independently configured, avoiding interference during loading and release, thus broadening its applicability.

[0035] Figure 3 In the figure, from the axial perspective, the anchoring arm 220 is a straight rod in the unfolded state, with a third visible mark 221 at each end. The binding ring 210 in the figure has an open part for installation around the plug 200. After it is in place, the binding ring 210 is squeezed to deform and close the open part.

[0036] Figure 4 In, with Figure 3 The difference is that, from an axial perspective, the anchoring arm 220 is S-shaped when deployed, while the binding ring 210 is shown in a closed position.

[0037] Figure 5 In, with Figure 4 The difference is that, from an axial perspective, the anchoring arm 220, when deployed, is arranged in a ring shape, forming a five-lobed structure overall.

[0038] In the above embodiments, the anchoring arms 220 do not overlap in the unfolded state, avoiding excessive radial space occupation in the compressed state. From a radial perspective, the anchoring arms 220 can expand radially outward and bend into an arc shape towards the distal end, or they can bend into an arc shape towards the proximal end. The end portion of the anchoring arm 220 can be upset or rounded to further reduce safety risks while ensuring positioning and coordination with surrounding tissues.

[0039] CombinationFigure 7 The process of machining the embolization component 200 is illustrated. In order to avoid interference with the exposed end of the anchoring arm 220 when the embolization component 200 is deformed, the embolization component 200 has a circumferential cutout 201 arranged around it. A retaining ring 210 is embedded in the circumferential cutout 201. In the embolization component 200, the part surrounded by the circumferential cutout 201 is clamped and fixed by the retaining ring 210. One end of the anchoring arm 220 can be pre-machined and fixed to the retaining ring 210, and the other end of the anchoring arm 220 extends outward in a radial direction. In the preset state, the anchoring arm 220 of the embolization component 200 is embedded in the circumferential incision 201. When the anchoring arm 220 tends to be implanted, it is compressed and deformed. During the deformation process, the presence of the circumferential incision 201 does not interfere with the anchoring arm 220. From the perspective of the implantation process in the body, the anchoring arm 220 is first released and its end abuts against and partially submerged in the surrounding tissue. During the subsequent expansion of the embolization component 200, since it is impossible to reach the pressure of the anchoring arm 220 on the tissue, the end of the anchoring arm 220 is exposed relative to the embolization component 200 (submerged in the surrounding tissue).

[0040] See Figure 6 The embolization component 200 is divided into a distal section 204 and a proximal section 205 along the axial direction by a binding ring 210. When the embolization component 200 is loaded, each anchoring arm 220 is brought together and abutted against the outer periphery of the distal section 204 to facilitate loading into the interventional catheter 400.

[0041] Considering the high positioning requirements and timing in wide-necked aneurysms, the embolization system of this embodiment also includes a delivery tube 300, which is slidably inserted into the interventional catheter 400. The delivery tube 300 and the embolization element 200 have a relative connected state and a disengaged state. In the connected state, the embolization element 200 is located on the distal side outside the delivery tube 300. When the position or posture is not good, the delivery tube 300 is moved proximally to pull the embolization element 200 into the interventional catheter 400, or to restrict the embolization element 200 from disengaging from the interventional catheter 400. Based on this, the timing of disengagement is controlled to ensure that the positioning of the embolization element 200 meets expectations. Then, the system switches to the disengaged state to allow the embolization element 200 to disengage from the delivery tube 300 and the interventional catheter 400, that is, to be released into the wide-necked aneurysm.

[0042] In order to cooperate with imaging equipment and observe the position of the embolization component 200 and the delivery tube 300 in real time, the distal end of the delivery tube 300 may be equipped with a second imaging mark 302. The binding ring 210 on the embolization component 200 can serve as an imaging mark. Taking the embolization component 200 as a spherical crown shape, it has a spatial axis. The interior of the distal section 204 is fixed with a core wire 230 extending along the axis by pre-embedding or molding and then threading. The core wire 230 can also serve as an imaging mark.

[0043] See Figure 7 , Figure 8In order to facilitate switching between the delivery tube 300 and the plug 200, the proximal section 205 is provided with an axial hole 202. An elastic wire 240 is provided in the axial hole 202. One end of the elastic wire 240 is integrally connected to the core wire 230 or separately fixedly connected, and the other end of the elastic wire 240 is connected to the first ball 250.

[0044] The delivery tube 300 is equipped with a pull wire 310, the proximal end of which is the operating end, and the distal end of which is equipped with a second ball 320. In the connected state, the first ball 250 is inserted into the delivery tube 300 and is located near the proximal end of the second ball 320. The first ball 250 is obstructed by the second ball 320 and remains within the delivery tube 300, thus preventing the plug 200 from completely disengaging. In the disengaged state, the first ball 250 passes over the second ball 320 to allow disengagement from the delivery tube 300. Of course, when disengagement is not required, the first ball 250 and the second ball 320 are restricted by the inner wall of the delivery tube 300 and cannot interchange positions. When disengagement is required, the inner wall of the delivery tube 300 can be released from the restriction. The first ball 250 and the second ball 320 can be metal balls with the same diameter, and the metal ball itself can also serve as a developing marker.

[0045] To accommodate the positional relationship between the first ball 250 and the plug 200 under different conditions, the elastic wire 240 has an initial spiral coiled state and a straightened state after being subjected to force. Figure 7 The diagram illustrates the straightened state. In this state, the first ball 250 extends beyond the embolization member 200. To prevent excessive dragging within the body after implantation, the proximal segment 205 has a receiving groove 203 formed by the outward expansion of the axial hole 202. The receiving groove 203 has an opening facing the proximal end. In the initial state, the elastic wire 240 pulls the first ball 250 into the receiving groove 203. In the preset and implanted states, the opening of the receiving groove 203 is closed by the embolization member 200 itself, thereby completely enveloping the elastic wire 240 and the first ball 250, further improving the safety of use.

[0046] The proximal end of the pull wire 310 is the operating end. The proximal end of the delivery tube 300 may be provided with an end cap. The operating end of the pull wire 310 is inside the delivery tube 300 and fixed to the end cap. The end cap is connected to the other parts of the delivery tube 300 through a breakable part. When in use, the delivery tube 300 and the end cap enclose the proximal end of the pull wire 3100 to avoid misoperation. When it is necessary to drive the pull wire 310 to move relative to the delivery tube 300, it can be broken or pulled at the breakable part to allow the end cap to pull the pull wire 310 and the second ball 320 towards the proximal end relative to the delivery tube 300.

[0047] Figures 8-12The illustration shows the implantation process of the embolic element 200 and also provides a corresponding structure for a delivery tube 300. The delivery tube 300 has a reduced-diameter section 330 at its distal end. In the connected state, both the first ball 250 and the second ball 320 are located within the reduced-diameter section 330, where the diameter of the reduced-diameter section 330 is smaller than the sum of the diameters of the first ball 250 and the second ball 320. In the connected state, under the constraint of the reduced-diameter section 330, the second ball 320 and the first ball 250 are difficult to misalign; that is, the first ball 250 cannot extend distally beyond the second ball 320. Since the second ball 320 is pulled by the pull wire 310 and cannot detach from the delivery tube 300, the first ball 250 and the embolic element 200 can remain connected. The delivery tube 300 can be used to adjust and restrict the implantation position of the embolic element 200, preventing it from deviating from the intended implantation position due to blood flow or compression from surrounding tissues.

[0048] When release is required, the pull wire 310 pulls the second ball 320 proximally relative to the delivery tube 300, causing the first ball 250 and the second ball 320 to move proximally out of the reduced diameter section 330. Figure 11 As can be seen, the delivery tube 300 is pushed against the plug 200 at the distal end to prevent it from shifting to the proximal end. Since part of the elastic wire 240 is still in a curved and tortuous filling position, the first ball 250 is allowed to move to the proximal side while the plug 200 remains in place.

[0049] In the delivery tube 300, the diameter of the proximal portion of the reduced-diameter section 330 is greater than or equal to the sum of the diameters of the first sphere 250 and the second sphere 320, allowing the second sphere 320 and the first sphere 250 to be misaligned, i.e., in a position where... Figure 11 In the middle of the release state, the restraint is released and the first ball 250 is allowed to pass over the second ball 320 to the distal side, so that the first ball 250 and the embolization member 200 are separated from the delivery tube 300, and the embolization member 200 is released.

[0050] See Figure 13 In another embodiment of this application, the delivery tube 300 is a straight tube as a whole, i.e., without a reduction in diameter. Although the distal end may be allowed to bend, its diameter remains basically unchanged, to distinguish it from the previously mentioned reduced-diameter section 330. Since the delivery tube 300 does not require a reduction in diameter, it can have a smaller overall diameter, making it suitable for complex interventional paths and applicable to a wider range of scenarios. In this embodiment, a release hole 301 is provided on the wall of the delivery tube 300. Of course, the diameter of the delivery tube 300 at the distal end is smaller than the sum of the diameters of the first sphere 250 and the second sphere 320. In the connected state, the second sphere 320 and the first sphere 250 are difficult to misalign due to the constraint of the delivery tube 300, i.e., the first sphere 250 cannot extend beyond the second sphere 320 to the distal end.

[0051] When release is required, the pull wire 310 pulls the second ball 320 proximally relative to the delivery tube 300, causing the first ball 250 and the second ball 320 to move proximally together until one of the first ball 250 and the second ball 320 partially enters the release hole 301, reducing interference with the other. At this point, the inner cavity of the delivery tube 300 allows the second ball 320 and the first ball 250 to be misaligned, i.e., in a state of... Figure 14 The first ball 250 is released from its detached state, allowing it to pass over the second ball 320 to the distal end, thereby detaching the first ball 250 and the embolic member 200 from the delivery tube 300 and releasing the embolic member 200.

[0052] In the connected state, since the first sphere 250 is located proximal to the second sphere 320, during disengagement, the first sphere 250 typically enters the disengagement hole 301 first, avoiding the second sphere 320 and moving further proximally until the first sphere 250 and the second sphere 320 are misaligned. However, because the first sphere 250 and the second sphere 320 are close together, in some cases, the second sphere 320 may enter the disengagement hole 301 first, avoiding the first sphere 250 and moving distally until the first sphere 250 and the second sphere 320 are misaligned.

[0053] See Figure 15 , Figure 16 In another embodiment of this application, to ensure accurate release, 2 to 4 release holes 301 are provided along the circumference of the delivery tube 300, for example, 3 holes. The diameter of each release hole 301 is smaller than the diameter of the first sphere 250 and the second sphere 320, so as to restrict the first sphere 250 and the second sphere 320 from exiting the release hole 301. Multiple release holes 301 can prevent the first sphere 250 and the second sphere 320 from directly missing the release hole 301 when moving towards the proximal end. Taking the first sphere 250 as an example in the figure, since the presence of multiple release holes 301 occupies most of the circumferential area of ​​the tube wall, the first sphere 250 will not miss the release hole 301 when moving towards the proximal end.

[0054] The release hole 301 can be a strip-shaped hole that extends spirally around the axis of the delivery tube 300 in space. When the delivery tube 300 is unfolded, it is an oblique strip-shaped hole with a relative length and width. The width of the release hole 301 is smaller than the diameter of the first sphere 250 and the second sphere 320, so as to restrict the first sphere 250 and the second sphere 320 from exiting the release hole.

[0055] Three release holes 301 are arranged circumferentially along the delivery tube 300. The central angle corresponding to the position of each release hole 301 is 60-150 degrees. For example, in the unfolded view, the area spanned by each release hole 301 (the horizontal direction in the figure) is greater than 1 / 3 of the area spanned by the delivery tube 300, which also ensures that the positions of all release holes 301 cover the entire circumferential area of ​​the delivery tube 300. Regardless of where the first sphere 250 and the second sphere 320 are in contact with the tube wall in the circumferential direction, at least one of them will contact and fall into the release hole 301 during the axial movement towards the proximal end, completely avoiding the possibility of release failure and improving the convenience and safety of operation.

[0056] Before the embolization component 200 and the anchoring arm 220 are housed in the interventional catheter 400, in order to keep the embolization component 200 in the loaded state and facilitate subsequent operations, a sheath can be wrapped around the outer periphery of the embolization component 200. The sheath also wraps around the anchoring arm 220. The sheath can be provided with a low-strength tear line or a tear guide port. When in use, the sheath is torn open and the embolization component 200 and the anchoring arm 220 are promptly transferred into the interventional catheter 400. This method allows for the separate storage and transportation of the interventional catheter 400 and other components, and the combination of different models of equipment is also more flexible.

[0057] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered to be within the scope of this specification. When technical features of different embodiments are embodied in the same drawing, it can be regarded as the drawing also disclosing examples of combinations of the various embodiments involved.

[0058] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. An embolization system based on wide-necked aneurysms, characterized in that, include: The embolization device is made of shape memory polymer foam. The embolization device includes, in order of increasing relative volume, a compressed loading state, a restricted expansion implantation state, and a fully expanded preset state. An anchoring arm is inserted into the embolization member. In a preset state, the anchoring arm is embedded inside the embolization member. In the implanted state, the end of the anchoring arm is exposed outside the embolization member for anchoring to the inner wall of the wide carotid aneurysm. An interventional catheter for receiving the embolic element in its loaded state; A delivery tube is slidably inserted within the interventional catheter, and the delivery tube has a relative connected state and a disengaged state with respect to the embolic element. In the connected state, the embolic element is located on the distal side outside the delivery tube, and in the disengaged state, the embolic element is allowed to detach from the delivery tube to be released into the wide carotid aneurysm.

2. The embolization system based on wide-necked aneurysms according to claim 1, characterized in that, The plug has a circumferentially arranged circumferential cut, and a retaining ring is embedded in the circumferential cut. In the plug, the part surrounded by the circumferential cut is clamped and fixed by the retaining ring. One end of the anchoring arm is fixed to the retaining ring, and the other end extends radially outward. In a preset state, the anchoring arm of the plug is embedded in the circumferential cut.

3. The embolization system based on wide-necked aneurysms according to claim 2, characterized in that, The number of anchoring arms is three to eight, and they are radially distributed around the outer periphery of the bundle ring. Each anchoring arm is straight, S-shaped, or self-circulated in a ring when unfolded.

4. The embolization system based on wide-necked aneurysms according to claim 2, characterized in that, The plug is axially divided into a distal section and a proximal section by the bundle ring. When the plug is loaded, each of the anchoring arms is brought together and abutted against the outer periphery of the distal section.

5. The embolization system based on wide-necked aneurysms according to claim 4, characterized in that, The embolization component is spherical and has a spatial axis. The distal segment has a core wire extending along the axis fixed inside by pre-embedding or threading after molding. The core wire also serves as a radiopaque marker.

6. The embolization system based on wide-necked aneurysms according to claim 5, characterized in that, The proximal segment is provided with an elastic wire, one end of which is integrally connected to the core wire or separately fixedly connected, and the other end of the elastic wire is connected to a first sphere; The delivery tube is provided with a pull wire, the proximal end of which is the operating end, and the distal end of which is provided with a second ball. When the delivery tube and the embolization are connected, the first ball is placed in the delivery tube and is located near the proximal end of the second ball. The first ball is blocked by the second ball and remains in the delivery tube. With the delivery tube and the plug in the detached state, the first ball passes over the second ball to allow disengagement from the delivery tube.

7. The embolization system based on wide-necked aneurysms according to claim 6, characterized in that, The elastic wire has an initial spiral coiled state and a straightened state after being stressed. In the straightened state, the first ball extends to the outside of the plug. The proximal segment has a receiving groove inside, and the receiving groove has an opening facing the proximal end. In the initial state, the elastic wire pulls the first ball into the receiving groove. In the preset state and the implanted state, the opening of the receiving groove is closed by the embolization member itself.

8. The embolization system based on wide-necked aneurysms according to claim 6, characterized in that, The distal end of the delivery tube has a reduced diameter section, and in the connected state, both the first sphere and the second sphere are located within the reduced diameter section. The diameter of the reduced-diameter section is smaller than the sum of the diameters of the first sphere and the second sphere. In the connected state, the first sphere is restrained by the reduced-diameter section and moves to the distal end past the second sphere. In the unloaded state, the pull wire pulls the second sphere to the proximal end relative to the delivery tube, causing the first sphere and the second sphere to move to the proximal end side out of the reduced-diameter section. In the delivery tube, the diameter of the portion located near the reduced diameter section is greater than or equal to the sum of the diameters of the first sphere and the second sphere, which is used to release the restraint and allow the first sphere to pass over the second sphere to the distal end.

9. The embolization system based on wide-necked aneurysms according to claim 6, characterized in that, The distal end of the delivery tube is a straight tube as a whole, and a release hole is provided on the tube wall; The diameter of the delivery tube is smaller than the sum of the diameters of the first sphere and the second sphere. In the connected state, the delivery tube restricts the first sphere from passing over the second sphere at the distal end. In the released state, the pull wire pulls the second ball proximally relative to the delivery tube, causing the first ball and the second ball to move proximally until at least one of the first ball and the second ball partially enters the release hole, allowing the first ball to be transferred from the proximal side of the second ball to the distal side of the second ball.

10. The embolization system based on wide-necked aneurysms according to claim 9, characterized in that, The release hole is a strip-shaped hole that extends spirally around the axis of the delivery tube and has a relative length and width, wherein the width of the release hole is smaller than the diameter of the first sphere and the second sphere, so as to restrict the first sphere and the second sphere from exiting the release hole.

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