Particle stent for portal vein, particle stent for cavity and kit thereof

Abstract

The present invention discloses a particle stent for portal vein, a particle stent for cavity and a kit thereof. The particle stent includes a fixing portion; a first parallel portion, including a plurality of first edges parallel to the length direction of the particle stent; a second parallel portion, including a plurality of second edges parallel to the length direction of the particle stent; a supporting portion, extending along the circumferential direction of the particle stent to provide radial supporting force for the first edge and the second edge; a particle filling portion, wherein each group of nickel-titanium alloy wires are mutually wound from the first end to the support starting point to form a first edge; and the first edge is dispersed into two nickel-titanium alloy wires from the support starting point, each nickel-titanium alloy wire is bent at the support end point, and is mutually wound with the adjacent group of nickel-titanium alloy wires from the support end point to the second end to form a second edge. The particle stent can not only realize the precise arrangement of radiation particles, but also avoid the displacement of cancer thrombi.

Description

Technical Field

[0001] The invention relates to a particle stent for portal vein, also relates to a particle stent for cavity, and also relates to a particle stent kit comprising the particle stent, belonging to the technical field of medical devices. Background Art

[0002] Treatment options for portal vein main trunk cancer thrombus include surgical resection, liver transplantation, targeted drugs, and portal vein stent implantation. Among them, surgical resection has a poor therapeutic effect, with a median survival period of only 6 months. Liver transplantation has a low long-term survival rate and is prone to waste liver resources. Targeted drugs are expensive, and the survival period is often only 2 to 3 months. Portal vein stent implantation has no therapeutic effect on cancer thrombus, and the blood flow is short.

[0003] At present, in order to achieve the treatment of portal vein main trunk cancer thrombus, on the basis of ordinary portal vein stent implantation, some people have proposed a portal vein stent that can be loaded with particles, and the treatment of cancer thrombus is achieved by loading radioactive particles. However, there is no internal radiotherapy stent for portal vein cancer thrombus treatment on the market, only ordinary stents for portal hypertension shunt. Such ordinary stents can only achieve palliative treatment of portal hypertension, and their stent structure is only used to dilate the portal vein, and there is no long-term radiotherapy treatment effect on cancer thrombus, so there is no need to place radioactive particles. Moreover, due to the limitation of the stent delivery path in portal vein cancer thrombus surgery, the radial size of the portal vein stent cannot be very large. Therefore, the ordinary portal vein stent with a mesh structure does not have much space to store radioactive particles, nor can it achieve accurate arrangement of radioactive particles, so that the dose of radioactive particles cannot meet the treatment needs. In addition, due to the fluidity of blood, it is very easy to cause the risk of cancer thrombus metastasis. Therefore, the industry is in urgent need of a special particle stent for portal vein cancer thrombus treatment. Summary of the invention

[0004] The primary technical problem to be solved by the present invention is to provide a particle stent for portal vein.

[0005] Another technical problem to be solved by the present invention is to provide a particle support for a cavity.

[0006] Another technical problem to be solved by the present invention is to provide a particle holder kit including the above-mentioned particle holder.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, there is provided a particle stent for portal vein, which is woven from nickel-titanium alloy wires and comprises:

[0009] A fixing part, including a first end and a second end, located at two ends of the particle support, and used to fix the particle support in the portal vein;

[0010] A first parallel portion is located in the middle area of ​​the particle support and close to the first end of the particle support, and the first parallel portion includes a plurality of first edges parallel to the length direction of the particle support;

[0011] A second parallel portion is located in the middle area of ​​the particle support and close to the second end of the particle support, and the second parallel portion includes a plurality of second edges parallel to the length direction of the particle support;

[0012] A support portion, connected between the first parallel portion and the second parallel portion, extending along the circumferential direction of the particle support to provide radial support force to the first edge and the second edge, each first edge or second edge is obtained by winding two nickel-titanium alloy wires;

[0013] The particle filling part includes a plurality of particle capsules for filling radioactive particles, wherein the plurality of particle capsules are evenly arranged on the first edge and the second edge.

[0014] The first parallel portion and the second parallel portion are woven differently from the fixed portion, so that the supporting force of the fixed portion is greater than that of the first parallel portion and the second parallel portion; and the first edge and the second edge are of equal length.

[0015] Each group of nickel-titanium alloy wires are mutually wound from the first end to the support starting point to form the first edge; and the first edge is dispersed into two nickel-titanium alloy wires from the support starting point, each nickel-titanium alloy wire is bent at the support end point, and is mutually wound with the adjacent group of nickel-titanium alloy wires from the support end point to the second end to form the second edge.

[0016] Preferably, the plurality of first edges and the plurality of second edges are staggered and parallel to each other;

[0017] A plurality of dispersed support wires are connected between the plurality of first edges and the plurality of second edges, and each of the support wires is arranged around the circumferential direction of the particle support to jointly constitute the support portion.

[0018] Preferably, a plurality of the first edges correspond to a plurality of the second edges one by one, and each of the first edges and the corresponding second edge are located on the same straight line;

[0019] A plurality of dispersed support wires are formed between the plurality of first edges and the plurality of second edges, and each of the support wires is arranged in a circumferential direction around the particle support to jointly constitute the support portion.

[0020] Preferably, the plurality of first edges are a plurality of mutually parallel first spiral wires, and the plurality of second edges are a plurality of mutually parallel second spiral wires;

[0021] The plurality of first spiral wires and the plurality of second spiral wires form a preset angle, and a plurality of dispersed support wires are formed between the plurality of first spiral wires and the plurality of second spiral wires, and each of the support wires is arranged around the circumferential direction of the particle support to jointly constitute the support portion.

[0022] Preferably, the particle capsule is formed on the first edge and the second edge by using a jet spinning process, so as to increase the supporting force of the first edge and the second edge and reduce the thickness of the particle capsule.

[0023] Preferably, the jet spinning process comprises the following steps:

[0024] S1: installing a preform mold on a first edge and a second edge in sequence; wherein the preform mold comprises particles and a fixing structure, wherein the particles are larger than the radioactive particles and are made of a soluble or heat-fusible material, and the fixing structure fixes the particles on one side of the first edge or the second edge;

[0025] S2: spraying a solution of the vascular membrane material in the form of a thread onto each preformed mold by a jet spinning device to form a particle capsule having a preset size encapsulating the preformed mold;

[0026] S3: Stop for a preset time until each particle capsule is cooled and shaped;

[0027] S4: immersing the entire particle support in a special solution to completely dissolve the preformed mold, thereby exposing the capsule structure of the particle capsule;

[0028] S5: cleaning the entire particle support to form a particle support having a plurality of particle capsules.

[0029] Preferably, a first support grid is formed between two adjacent first edges, and a second support grid is formed between two adjacent second edges;

[0030] The first support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the first edges; the second support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the second edges,

[0031] In the circumferential direction of the stent, the first support grid and the second support grid do not cover the entire circumference.

[0032] According to a second aspect of an embodiment of the present invention, there is provided a particle support for a cavity, which is woven from metal wires and includes:

[0033] A fixing part, including a first end and a second end, located at two ends of the particle support, and used to fix the particle support in the portal vein;

[0034] A first parallel portion is located in the middle area of ​​the particle support and close to the first end of the particle support, and the first parallel portion includes a plurality of first edges parallel to the length direction of the particle support;

[0035] A second parallel portion is located in the middle area of ​​the particle support and close to the second end of the particle support, and the second parallel portion includes a plurality of second edges parallel to the length direction of the particle support;

[0036] A support portion, connected between the first parallel portion and the second parallel portion, extending along the circumferential direction of the particle support to provide radial support force to the first edge and the second edge;

[0037] The particle filling part includes a plurality of particle capsules for filling radioactive particles, wherein the plurality of particle capsules are evenly arranged on the first edge and the second edge.

[0038] Wherein, the first parallel portion and the second parallel portion are woven differently from the fixing portion, so that the supporting force of the fixing portion is greater than that of the first parallel portion and the second parallel portion;

[0039] Wherein, each group of metal wires are mutually wound from the first end to the support starting point to form the first edge; and the first edge is dispersed into two metal wires from the support starting point, each metal wire is bent at the support end point, and is mutually wound with the adjacent group of metal wires from the support end point to the second end to form the second edge.

[0040] Preferably, the particle capsule is formed on the first edge and the second edge by using a jet spinning process, so as to increase the supporting force of the first edge and the second edge and reduce the thickness of the particle capsule.

[0041] Preferably, a first support grid is formed between two adjacent first edges, and a second support grid is formed between two adjacent second edges;

[0042] The first support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the first edges; the second support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the second edges,

[0043] In the circumferential direction of the stent, the first support grid and the second support grid do not cover the entire circumference.

[0044] According to a third aspect of an embodiment of the present invention, there is provided a particle support kit, comprising:

[0045] The particle stent for portal vein as described above, or the particle stent for cavity as described above;

[0046] A plurality of radioactive particles are used to be respectively filled into the particle capsules of the particle holder based on the TPS (treatment planning system) preoperative planning;

[0047] The expandable stent is braided into a cylindrical shape so as to be in a contracted state when under stress and in an expanded state when not under stress;

[0048] The expansion stent can be delivered into the particle stent in a contracted state, and provide radial support force to the particle stent in an expanded state.

[0049] Compared with the prior art, the present invention has the following technical effects:

[0050] 1. It can achieve precise arrangement of radioactive particles.

[0051] First, the fixed parts at both ends of the particle stent have a mesh structure that is woven differently from the parallel parts in the middle region, so the fixed parts have greater support, making the support at both ends of the stent stronger, thereby fixing the particle stent in the portal vein to prevent the stent from shifting.

[0052] Secondly, two or more parallel parts parallel to each other are formed in the middle area of ​​the particle holder, and each parallel part is arranged with a particle capsule for filling with radioactive particles; and the parallel parts are interconnected with supporting wires to increase the supporting force of the two parallel parts, prevent the parallel parts from collapsing, and ensure that the parallel parts have a certain supporting strength, thereby avoiding radial deviation of the radioactive particles and affecting the dosage accuracy, thereby achieving precise arrangement of the radioactive particles.

[0053] Thirdly, the axial length of the seed stent remains unchanged in the compressed or expanded state, so the radioactive particles in the seed capsule will not shift in position, thereby ensuring accurate positioning of the radioactive particles and improving the radiotherapy effect.

[0054] Fourthly, since the middle part of the particle stent has only a plurality of parallel parts and a plurality of particle capsules, the size is small in the contracted state, and it is suitable for stent delivery in tortuous cavities.

[0055] Fifth, the particle capsule formed by the jet spinning process is more advantageous because it has a compact and stable structure, with strong connections between fibers, and is not prone to falling off from the parallel part or shifting relative to the parallel part. Therefore, compared with the sewing process, the particle capsule is not easily deformed, damaged or shifted during use, thereby keeping the radiation particles in the position planned before TPS surgery, improving accuracy.

[0056] 2. It can prevent the displacement of cancer thrombus.

[0057] First, the supporting wires connected to each other between the two parallel parts can increase the supporting force of the two parallel parts, so that the supporting force of the parallel parts can be used to squeeze the particle capsule toward the inner wall of the cavity, thereby supporting and fixing the cancer thrombus to avoid the metastasis of the cancer thrombus under the action of blood flow.

[0058] Secondly, more preferably, a support grid may be provided in a partial area on the two parallel portions, so as to support the cancer thrombus by using the support grid, thereby improving the fixation effect on the cancer thrombus.

[0059] Third, if the support of the parallel parts is not enough to support the cancer thrombus, an internal stent can be released between the parallel parts for support, or a balloon can be used to expand the stent to ensure stable support for the cancer thrombus and avoid displacement of the cancer thrombus. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A schematic structural diagram of a particle stent for portal vein provided by the first embodiment of the present invention;

[0061] Figure 2 A schematic diagram of particle dosage of a particle stent for portal vein provided by the first embodiment of the present invention;

[0062] Figure 3 A schematic structural diagram of another particle stent for portal vein provided by the first embodiment of the present invention;

[0063] Figure 4 A schematic structural diagram of a particle stent for portal vein provided by the second embodiment of the present invention;

[0064] Figure 5 A schematic diagram of particle dosage of a particle stent for portal vein provided by the second embodiment of the present invention;

[0065] Figure 6 A schematic structural diagram of a particle stent for portal vein provided by the third embodiment of the present invention;

[0066] Figure 7 A schematic diagram of particle dosage of a particle stent for portal vein provided in the third embodiment of the present invention;

[0067] Figure 8 A schematic structural diagram of a particle stent kit for portal vein provided by a fourth embodiment of the present invention;

[0068] Fig. 9 This is a schematic diagram of the front view of the expanded stent in the fourth embodiment of the present invention;

[0069] Fig.10 A schematic structural diagram of another particle stent kit for portal vein provided in the fourth embodiment of the present invention. DETAILED DESCRIPTION

[0070] The technical content of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0071] The particle stent and kit for portal vein provided in the embodiments of the present invention can be used in cavities, including blood vessels, airways, urethra, cervix, etc., and only the portal vein is used as an example for illustration, but this does not constitute a limitation of the present invention.

[0072] As is known to all, obstruction of portal vein blood flow is one of the main causes of portal hypertension. Increased portal vein pressure will form collateral circulation. Therefore, portal vein stents need to ensure smooth blood flow to avoid inducing or aggravating portal hypertension due to the stent. In other words, the stent as a whole (whether it is the end of the stent or the middle) needs to have sufficient wall adhesion to ensure that the stent has the least effect on the flow rate of blood flow. Moreover, the tortuosity of the portal vein makes stent design more difficult (the compliance of the stent should be high during delivery; the support force of the stent should be high during release). Therefore, conventional grid-like vascular stents often have insufficient support force and are easy to fall off after implantation. To this end, the particle stent for the portal vein provided in an embodiment of the present invention can solve these problems.

[0073] First embodiment

[0074] like Figure 1 and Figure 2 As shown, a particle stent 10 for portal vein provided by the first embodiment of the present invention comprises a fixing portion 11, a supporting portion 12, a first parallel portion 13, a second parallel portion 14 and a particle filling portion 15. The fixing portion 11, the supporting portion 12, the first parallel portion 13, the second parallel portion 14 and the particle filling portion 15 are all distributed in the circumferential direction of the particle stent, thereby avoiding obstruction of blood flow and ensuring that the expanded stent is delivered to the inside of the particle stent (described in detail later).

[0075] Specifically, in the present embodiment, the fixing part 11 is located at the two ends of the particle support 10 and matches the size of the portal vein, so as to fix the particle support 10 in the portal vein. Under the release state (expanded state) not subject to external force, the weaving mode of the fixing part 11 is different from the parallel part, so that the supporting force of the fixing part is greater than the first parallel part and the second parallel part. Such a design makes the fixing part 11 have a greater supporting force on the inner wall of the cavity after being released in the portal vein, so that the positioning effect is better. However, because the supporting force of the first parallel part and the second parallel part is less than the fixing part, and the particle capsule and the radioactive particles are fixed, the first parallel part and the second parallel part are difficult to expand in the radial direction.

[0076] The first parallel portion 13 is located in the middle area of ​​the particle support 10 and close to the first end of the particle support (i.e. Figure 1 The first parallel portion 13 includes a plurality of first edges 101 parallel to the length direction of the support. The second parallel portion 14 is located in the middle area of ​​the particle support 10 and close to the second end of the particle support (i.e. Figure 1 D end in the middle), the second parallel portion 14 includes a plurality of second edges 102 parallel to the length direction of the stent. The support portion 12 is connected between the first parallel portion 13 and the second parallel portion 14 to support the inner wall of the cavity of the portal vein, and to keep the plurality of first edges 101 parallel, and the plurality of second edges 102 parallel. The particle filling portion 15 includes a plurality of particle capsules 151 for filling radioactive particles, and the plurality of particle capsules 151 are evenly arranged on the first edge 101 and the second edge 102. Here, the parallel first edge and the second edge only extend in the length direction and do not extend in the circumferential direction. Here, the parallel first edge and the second edge only extend in the length direction and do not extend in the circumferential direction. Such a design ensures that the length of the first parallel portion and the second parallel portion will not change in the length direction, that is, the stent does not have an axial shrinkage phenomenon.

[0077] In this embodiment, the particle stent 10 is woven into a cylindrical shape by a plurality of nickel-titanium alloy wires 1, so that the two ends of the particle stent respectively form a fixing portion 11, and the middle of the particle stent is formed with a support portion 12 for supporting the inner wall of the portal vein. Each nickel-titanium alloy wire 1 corresponds to a preset path, so that each nickel-titanium alloy wire can be wound and formed according to its own preset path. The nickel-titanium alloy wires with overlapping paths are intertwined to form edges; each nickel-titanium alloy wire 1 is bent in the middle of the particle stent 10 to form a support wire of a preset length, and all the support wires located in the middle of the particle stent together constitute the support portion 12.

[0078] Specifically, in this embodiment, the plurality of nickel-titanium alloy wires of the particle support 10 are divided into a plurality of groups. Here, only nickel-titanium alloy wires are used as an example for illustration, and other metal wires (magnesium alloy) may also be used. The number of nickel-titanium alloy wires is twice the number of parallel portions. That is, each first edge or second edge in the parallel portion is obtained by winding two nickel-titanium alloy wires. Each group of nickel-titanium alloy wires is wound from the first end (i.e., Figure 1 The A end of the support) is wound around each other to the starting point of the support (i.e. Figure 1 The first edge 101 is formed by the support starting point B and the plurality of first edges 101 together form the first parallel portion. In addition, the first edge 101 is dispersed into two nickel-titanium alloy wires from the support starting point B, each of which is bent at the support end point C, and is intertwined with the adjacent group of nickel-titanium alloy wires from the support end point C to the second end of the particle support (i.e. Figure 1 The D end of the particle support 10 is formed by winding the adjacent or opposite first edges 101 at the A end and winding the adjacent or opposite second edges 102 at the D end to form the second parallel portion. Thus, the fixing portions 11 are formed at both ends of the particle support 10. Accordingly, all the dispersed nickel-titanium alloy wires between the support starting point B and the support end point C together constitute the support portion 12. In other words, each of the first edges 101 is wound by two nickel-titanium alloy wires; each of the second edges 102 is wound by two nickel-titanium alloy wires.

[0079] For example, the first first edge is wound by X11 and X12 (X11 and X12 are mutually called "pair wires", the second first edge is wound by X21 and X22; the third first edge is wound by X31 and X32, and the fourth first edge is wound by X41 and X42. The first second edge is wound by Y11 and Y12, the second second edge is wound by Y21 and Y22; the third second edge is wound by Y31 and Y32, and the fourth second edge is wound by Y41 and Y42. At point B, X11 to X42 are divided into 8 nickel-titanium alloy wires (at a point perpendicular to the support The first edge is an example of a first edge. At point B, the intertwined X11 and X12 are divided into single wires and dispersed into supporting parts 12 in the circumferential direction. X11 is adjacent to X42 of the fourth first edge, and X11 and X42 are respectively wound as Y11 and Y12 as the first second edge. Similarly, X12 is adjacent to X21 of the second edge, and X12 and X21 are respectively wound as Y21 and Y22 as the second second edge.

[0080] More preferably, the first edge 101 and the second edge 102 are equal or nearly equal in length. Such a design enables the support portion to be located in the middle in the length direction, thus providing a better support effect.

[0081] It is understandable that the fixing parts 11 at both ends of the particle holder 10 can not only conform to the shape of the portal vein, so as to facilitate insertion into the portal vein, but also provide a certain support effect to ensure the stability of the particle holder 10 and prevent the holder from shifting. In addition, since the middle area of ​​the particle holder 10 is formed with a support part 12 extending in the circumferential direction, it is possible to avoid the middle area of ​​the particle holder 10 from collapsing or closing together, thereby providing stable support for the radioactive particles, avoiding the relative position of the radioactive particles and the cancer thrombus from shifting, and thus ensuring the radiotherapy effect.

[0082] In addition, in this embodiment, the plurality of first edges 101 and the plurality of second edges 102 are mutually offset and parallel, and a plurality of dispersed support wires are connected between the plurality of first edges 101 and the plurality of second edges 102, and each support wire is arranged in the circumferential direction of the particle holder 10 to jointly constitute the support portion 12. Thus, the support portion 12 can increase the support force of the two parallel portions, prevent the parallel portions from collapsing, and ensure that the two parallel portions have a certain support strength, thereby avoiding radial deviation of the radiation particles and affecting the dosage accuracy, which is conducive to the accurate arrangement of the radiation particles.

[0083] In addition, in the above embodiment, preferably, the fixing portion 11 can be elastically contracted along the axial direction of the particle stent 10, and since the middle region of the particle stent forms two parallel portions, which have no compression-elongation characteristics in the length direction of the stent, the axial length of the parallel portions remains unchanged in the compressed state or the expanded state, thereby ensuring reliable positioning in the length direction of the stent of the particle filling portion. Thus, by radially compressing the particle stent 10, it is convenient to deliver the particle stent 10 into the cavity, and since the axial length of the particle stent 10 remains unchanged when changing between the contracted state and the expanded state, the radioactive particles installed on the particle stent 10 will not be displaced, thereby facilitating accurate radiotherapy of the radiation particle dose.

[0084] like Figure 2 As shown, in the above embodiment, the monofilaments in the support portion 12 extend in both the length direction and the circumferential direction of the stent, so the first edge 101 and the second edge 102 are offset parallel (that is, any one of the first edges 101 and any one of the second edges are not on the same straight line, but deviate from each other in the circumferential direction). Such offset parallelism improves the radial support force of the stent. Therefore, preoperative planning can be carried out through the radiotherapy planning system (TPS, Treatment Planning System) to determine the particle dose size, which is conducive to the accurate implementation of the particle dose. In addition, accurate postoperative evaluation can be carried out to safely and effectively exert the effect of internal radiotherapy.

[0085] In the above embodiment, preferably, as the length of the fixing portion 11 is shortened, the support strength of the particle holder 10 is increased. It is understandable that, since the supporting portion 12 provides a supporting force, the length of the fixing portion 11 can be shortened (properly reducing the supporting force), so that when multiple particle holders 10 are placed, adjacent particle holders can be closer together to avoid the distance between adjacent particle holders 10 being too large (radiation particles cannot be arranged in this area) and radiotherapy cannot be achieved, which is conducive to improving the effect of radiotherapy.

[0086] In the above embodiment, preferably, the particle capsule 151 is made of vascular membrane material or silicone material, which is conducive to compressing the particle capsule 151 so as to facilitate the overall delivery into the cavity. In addition, the outer surface of the particle capsule 151 is coated with a super lubricating coating to reduce the friction between the blood and the particle capsule 151, thereby avoiding the formation of thrombus and improving the safety of particle stent implantation. In addition, the inner surface of the particle capsule 151 is also sprayed with a sustained-release targeted drug, so that while using radioactive particles for radiotherapy, it is also possible to use sustained-release targeted drugs for drug therapy to provide a more effective treatment plan.

[0087] In the above embodiment, preferably, Figure 3 As shown, a first support grid 110 is also formed between two adjacent first edges 101, and a second support grid 120 is also formed between two adjacent second edges 102. Among them, the first support grid 110 and / or the second support grid 120 are formed by interlacing multiple nickel-titanium alloy wires. The first support grid is a grid formed by winding multiple nickel-titanium alloy wires between the first edges; the second support grid is a grid formed by winding multiple nickel-titanium alloy wires between the second edges. Moreover, in the circumferential direction of the stent, neither the first support grid nor the second support grid covers the entire circumference. For example, among the four first edges, the first support grid is formed between the first and second first edges; and the first support grid is formed between the third and fourth first edges. However, there is no first support grid between the second and third, and the first and fourth first edges. Such a design takes into account the stent design requirements of greater support force (improving wall adhesion) and smaller radial size (convenient delivery).

[0088] It can be understood that the use of the first support grid 110 and the second support grid 120, in conjunction with the support portion 12, can further improve the support strength of the particle stent 10, so as to ensure the support effect of the particle stent 10 on the inner wall of the portal vein, and avoid collapse or close-up of any position of the particle stent 10. In addition, in the above embodiment, preferably, the first support grid 110 and / or the second support grid 120 are also formed with a structural reinforcement point 130 ( Figure 3 Only one reinforcement point is shown in the figure) to further increase the structural strength of the particle support 10.

[0089] Second embodiment

[0090] like Figure 4 and Figure 5 As shown, the particle stent for portal vein provided by the second embodiment of the present invention is different from the first embodiment in that the structure of the particle stent is different.

[0091] Specifically, in this embodiment, the plurality of first edges 101 correspond to the plurality of second edges 102 one by one, and each first edge 101 is located on the same straight line as the corresponding second edge 102. In addition, a dispersed support wire is formed between adjacent first edges 101. Each support wire is arranged in the circumferential direction of the particle support 10 to connect adjacent first edges 101, and all support wires together constitute the support portion 12.

[0092] It is understandable that in this embodiment, the winding path of each nickel-titanium alloy wire is different from the winding path of each nickel-titanium alloy wire in the first embodiment, thus forming two different structural forms of particle stents. Among them, in this embodiment, the winding path of each nickel-titanium alloy wire can be adaptively set as needed, which is not specifically explained here, but what needs to be ensured is: first, the winding method cannot be too complicated; second, no breakpoints or overlaps can occur during the winding process; third, the size of the particle stent after winding needs to be able to be delivered into the portal vein.

[0093] In this embodiment, the functions of the fixing portion 11 and the supporting portion 12 are the same as those of the first embodiment, except that the specific structural forms are slightly different, which will not be described in detail here.

[0094] In addition, it should be noted that, since each first edge 101 is located on the same straight line as the corresponding second edge 102 , it is easier to sew the particle capsule 151 , thereby improving the convenience of production.

[0095] Third embodiment

[0096] like Figure 6 and Figure 7 As shown, the particle stent for portal vein provided by the third embodiment of the present invention is different from the first embodiment in that the structure of the particle stent 10 is different.

[0097] Specifically, in this embodiment, the plurality of first edges 101 are a plurality of mutually parallel first spiral wires, and the plurality of second edges 102 are a plurality of mutually parallel second spiral wires. In addition, the plurality of first spiral wires 101 and the plurality of second spiral wires 102 form a preset angle, and a plurality of support wires are formed between the plurality of first spiral wires 101 and the plurality of second spiral wires 102, each support wire being arranged in the circumferential direction of the particle support to jointly constitute the support portion 12. Here, the parallel first edges and second edges extend not only in the length direction, but also in the circumferential direction.

[0098] In this embodiment, the functions of the fixing portion 11 and the supporting portion 12 are the same as those of the first embodiment, except that the specific structural forms are slightly different, which will not be described in detail here.

[0099] Fourth embodiment

[0100] like Figure 8 As shown, a particle stent kit for portal vein provided by the fourth embodiment of the present invention comprises the particle stent 10 of the first embodiment or the second embodiment and a plurality of radioactive particles 20. The particle stent 10 is used to be delivered to the lesion position of the portal vein to support the portal vein; the plurality of radioactive particles 20 are respectively filled in the particle capsule 151 at specific positions based on the TPS preoperative planning for radiotherapy.

[0101] In this embodiment, each particle capsule 151 is formed on the first edge 101 or the second edge 102 by a process of jet spinning or sewing, and a particle capsule 151 is arranged at a specific interval (e.g., 10 mm) on the first edge 101 and the second edge 102, thereby forming a plurality of particle capsules 151 (e.g., 3 to 5). One end of each particle capsule 151 is closed, and the other end forms a cutout with a preset angle, so that the radioactive particles 20 can be filled into the bottom of the particle capsule from the cutout, so that the number of radioactive particles loaded can be selected according to needs to adapt to radiotherapy in different situations.

[0102] It can be understood that in this embodiment, a support portion 12 can be formed on the particle bracket 10 to increase the supporting force of the particle bracket 10, and a particle capsule can be formed around the first edge and / or the second edge of the particle bracket 10 by cooperating with the jet spinning or sewing process, thereby ensuring that the particle bracket 10 has sufficient supporting strength and reducing the overall size of the particle bracket 10 for easy delivery.

[0103] It should be noted that the use of jet spinning technology to form particle capsules can improve the support of the parallel part of the particle support to increase the support force of the support. The jet spinning process closely and reliably attaches the fiber to the nickel-titanium alloy wire, and the closely attached fiber is equivalent to increasing the nickel-titanium alloy wire diameter, thereby improving the rigidity of the nickel-titanium alloy wire, and then improving the support force of the parallel part. Moreover, since the particle capsule fibers formed by the jet spinning process are firmly connected and not easy to fall off or move, a particle capsule with a thinner thickness can be used, which is conducive to reducing the size of the support (or increasing the number of the first edge and the second edge at the same size, thereby increasing the number of particle capsules, and then increasing the number of particles that can be loaded, to improve the range and intensity of radiotherapy). The jet spinning process has the characteristics of a short process flow, and the fiber is directly made into cloth, thereby reducing the time and labor required in the sewing process, and significantly improving production efficiency. Moreover, since the first edge and the second edge are disconnected by the supporting wire in the first embodiment of the present invention, it is impossible to sew the particle capsule on the first edge and the second edge at the same time using a sewing process, which requires sewing twice, increasing the manufacturing cost. However, the particle capsule can be formed on the first edge and the second edge at the same time by jet spinning. For the parallel part of the spiral, since it is not a straight line, the sewing process is not applicable and only the jet spinning process can be used.

[0104] In this embodiment, the process of forming the radioactive particles 20 by jet spinning is as follows:

[0105] S1: installing the preforming mold on the first edge 101 and the second edge 102 in sequence; wherein the preforming mold includes particles and a fixing structure, the particles are larger than the radioactive particles and are made of soluble or heat-meltable materials, and the fixing structure fixes the particles on one side of the first edge 101 or the second edge 102;

[0106] S2: spraying a solution of the vascular membrane material in the form of a thread onto each preformed mold by a jet spinning device to form a particle capsule having a preset size encapsulating the preformed mold;

[0107] S3: Stop for a preset time until each particle capsule is cooled and shaped;

[0108] S4: immersing the entire particle support 10 in a special solution to completely dissolve the preformed mold, thereby exposing the capsule structure of the particle capsule;

[0109] S5: Cleaning the entire particle holder 10 to form a particle holder 10 having a plurality of particle capsules.

[0110] In the above embodiment, preferably, the particle stent kit further includes an expansion stent 30. Specifically, Fig. 9As shown, the expansion stent 30 is woven into a tube shape so as to be in a contracted state under stress and in an expanded state under no stress. Thus, the expansion stent 30 can be delivered to the inside of the particle stent 10 in a contracted state and then released to provide sufficient support force to the particle stent in an expanded state. It is understandable that Fig.10 As shown, in this embodiment, the expansion stent 30 is used as an auxiliary support tool. When the support strength of the particle stent 10 itself in a specific cavity cannot meet the support requirements, the expansion stent 30 can be inserted into the particle stent 10 to improve the support capacity of the particle stent 10.

[0111] It is understandable that the expansion stent 30 can directly use the internal stent commonly used in the art, which will not be described in detail here.

[0112] In summary, the particle stent for portal vein provided by the embodiment of the present invention has the following technical effects:

[0113] 1. It can achieve precise arrangement of radioactive particles.

[0114] First, the mesh structure of the fixed part at both ends of the particle stent is obtained by a different weaving method relative to the parallel part in the middle area, so the supporting force of the fixed part is greater, thereby making the supporting force at both ends of the stent stronger, thereby fixing the particle stent in the portal vein to prevent the stent from shifting.

[0115] Secondly, two or more parallel parts parallel to each other are formed in the middle area of ​​the particle holder, and each parallel part is arranged with a particle capsule for filling with radioactive particles; and the parallel parts are interconnected with supporting wires to increase the supporting force of the two parallel parts, prevent the parallel parts from collapsing, and ensure that the parallel parts have a certain supporting strength, thereby avoiding radial deviation of the radioactive particles and affecting the dosage accuracy, thereby achieving precise arrangement of the radioactive particles.

[0116] Thirdly, the axial length of the seed stent remains unchanged in the compressed or expanded state, so the radioactive particles in the seed capsule will not shift in position, thereby ensuring accurate positioning of the radioactive particles and improving the radiotherapy effect.

[0117] Fourthly, since the particle stent has only a plurality of parallel parts and a plurality of particle capsules in the middle, the size is small in the contracted state, and is suitable for stent delivery in tortuous cavities.

[0118] Fifth, the particle capsule formed by the jet spinning process is more advantageous because it has a compact and stable structure, with strong connections between fibers, and is not prone to falling off from the parallel part or shifting relative to the parallel part. Therefore, compared with the sewing process, the particle capsule is not easily deformed, damaged or shifted during use, so that the radiation particles remain in the position planned before TPS surgery.

[0119] 2. It can prevent the displacement of cancer thrombus.

[0120] First, the supporting wires connected to each other between the two parallel parts can increase the supporting force of the parallel parts, which can avoid the displacement of the particle stent to reduce the detachment and metastasis of the cancer thrombus, and use the supporting force of the parallel parts to squeeze the particle capsule toward the inner wall of the cavity, thereby supporting and fixing the cancer thrombus to avoid the metastasis of the cancer thrombus under the action of blood flow.

[0121] Secondly, more preferably, a support grid may be provided in a partial area on the two parallel portions, so as to support the cancer thrombus by using the support grid, thereby improving the fixation effect on the cancer thrombus.

[0122] Third, if the support of the parallel parts is not enough to support the cancer thrombus, an internal stent can be released between the parallel parts for support, or a balloon can be used to expand the stent to ensure stable support for the cancer thrombus and avoid displacement of the cancer thrombus.

[0123] Fourthly, the particle capsule is formed by the jet spinning process, and the fiber is used to increase the supporting force of the parallel part to avoid the metastasis of cancer thrombus.

[0124] 3. Support wires are used to ensure that after the stent is released, both the end and the parallel part can adhere to the wall well (radially expand) to maintain smooth blood flow; and the jet spinning process is used to reduce the thickness of the particle capsule, which is more conducive to improving the wall adhesion effect of the parallel part.

[0125] 4. Use jet spinning technology to improve production efficiency and reduce costs.

[0126] It should be noted that the above-mentioned multiple embodiments are only examples, and the technical solutions of various embodiments can be combined, all of which are within the protection scope of the present invention.

[0127] It should be understood that the orientation or positional relationship indicated by the terms "thickness", "up", "down", "horizontal", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0128] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0129] The particle stent for portal vein, the particle stent for cavity and the kit thereof provided by the present invention are described in detail above. For a person skilled in the art, any obvious modification made to the particle stent without departing from the essence of the present invention will constitute an infringement of the patent right of the present invention and the person shall bear the corresponding legal liability.

Claims

1. A particle stent for portal vein, woven from nickel-titanium alloy wire, characterized in that include: A fixing part, including a first end and a second end, located at two ends of the particle support, and used to fix the particle support in the portal vein; A first parallel portion is located in the middle area of ​​the particle support and close to the first end of the particle support, and the first parallel portion includes a plurality of first edges parallel to the length direction of the particle support; A second parallel portion is located in the middle area of ​​the particle support and close to the second end of the particle support, and the second parallel portion includes a plurality of second edges parallel to the length direction of the particle support; A support portion, connected between the first parallel portion and the second parallel portion, extending along the circumferential direction of the particle support to provide radial support force to the first edge and the second edge, each first edge or second edge is obtained by winding two nickel-titanium alloy wires; A particle filling part, comprising a plurality of particle capsules for filling radioactive particles, wherein the plurality of particle capsules are evenly arranged on the first edge and the second edge; The first parallel portion and the second parallel portion are woven differently from the fixing portion, so that the fixing portion has a greater supporting force than the first parallel portion and the second parallel portion; and the first edge and the second edge are of equal length; Each group of nickel-titanium alloy wires are mutually wound from the first end to the support starting point to form the first edge; and the first edge is dispersed into two nickel-titanium alloy wires from the support starting point, each nickel-titanium alloy wire is bent at the support end point, and is mutually wound with the adjacent group of nickel-titanium alloy wires from the support end point to the second end to form the second edge; A plurality of dispersed support wires are connected between the plurality of first edges and the plurality of second edges, and each of the support wires is arranged around the circumferential direction of the particle support to jointly constitute the support portion.

2. The particle support according to claim 1, characterized in that: The plurality of first edges and the plurality of second edges are staggered and parallel to each other.

3. The particle support according to claim 1, characterized in that: A plurality of the first edges correspond to a plurality of the second edges one by one, and each of the first edges and the corresponding second edge are located on the same straight line.

4. The particle support according to claim 1, characterized in that: The plurality of first edges are a plurality of mutually parallel first spiral wires, and the plurality of second edges are a plurality of mutually parallel second spiral wires; The plurality of first spiral wires and the plurality of second spiral wires form a preset angle.

5. The particle support according to any one of claims 1 to 4, characterized in that: The particle capsule is formed on the first edge and the second edge by using a jet spinning process, so as to increase the supporting force of the first edge and the second edge and reduce the thickness of the particle capsule.

6. The particle support as claimed in claim 5, characterized in that The jet spinning process comprises the following steps: S1: installing a preform mold on a first edge and a second edge in sequence; wherein the preform mold comprises particles and a fixing structure, wherein the particles are larger than the radioactive particles and are made of a soluble or heat-fusible material, and the fixing structure fixes the particles on one side of the first edge or the second edge; S2: spraying a solution of the vascular membrane material in the form of a thread onto each preformed mold by a jet spinning device to form a particle capsule having a preset size encapsulating the preformed mold; S3: Stop for a preset time until each particle capsule is cooled and shaped; S4: immersing the entire particle support in a special solution to completely dissolve the preformed mold, thereby exposing the capsule structure of the particle capsule; S5: cleaning the entire particle support to form a particle support having a plurality of particle capsules.

7. The particle support according to claim 5, characterized in that: A first support grid is formed between two adjacent first edges, and a second support grid is formed between two adjacent second edges; The first support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the first edges; the second support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the second edges, In the circumferential direction of the stent, the first support grid and the second support grid do not cover the entire circumference.

8. A particle stent for a cavity, woven from metal wires, characterized in that include: A fixing part, including a first end and a second end, located at two ends of the particle support, and used to fix the particle support in the portal vein; A first parallel portion is located in the middle area of ​​the particle support and close to the first end of the particle support, and the first parallel portion includes a plurality of first edges parallel to the length direction of the particle support; A second parallel portion is located in the middle area of ​​the particle support and close to the second end of the particle support, and the second parallel portion includes a plurality of second edges parallel to the length direction of the particle support; A support portion, connected between the first parallel portion and the second parallel portion, extending along the circumferential direction of the particle support to provide radial support force to the first edge and the second edge; The particle filling part includes a plurality of particle capsules for filling radioactive particles, wherein the plurality of particle capsules are evenly arranged on the first edge and the second edge. The first parallel portion and the second parallel portion are woven differently from the fixing portion, so that the fixing portion has a greater supporting force than the first parallel portion and the second parallel portion; Each group of metal wires is mutually wound from the first end to the support starting point to form the first edge; and the first edge is dispersed into two metal wires from the support starting point, each metal wire is bent at the support end point, and is mutually wound with the adjacent group of metal wires from the support end point to the second end to form the second edge; A plurality of dispersed support wires are connected between the plurality of first edges and the plurality of second edges, and each of the support wires is arranged around the circumferential direction of the particle support to jointly constitute the support portion.

9. The particle support according to claim 8, characterized in that: The particle capsule is formed on the first edge and the second edge by using a jet spinning process, so as to increase the supporting force of the first edge and the second edge and reduce the thickness of the particle capsule.

10. The particle support according to claim 9, characterized in that: A first support grid is formed between two adjacent first edges, and a second support grid is formed between two adjacent second edges; The first support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the first edges; the second support grid is a grid formed by winding a plurality of nickel-titanium alloy wires between the second edges, In the circumferential direction of the stent, the first support grid and the second support grid do not cover the entire circumference.

11. A particle support kit, characterized in that include: The particle stent for portal vein according to any one of claims 1 to 7, or the particle stent for cavity according to any one of claims 8 to 10; A plurality of radioactive particles are used to be respectively filled into the particle capsules of the particle stent based on the TPS preoperative planning; The expandable stent is braided into a cylindrical shape so as to be in a contracted state when under stress and in an expanded state when not under stress; The expansion stent can be delivered into the particle stent in a contracted state, and provide radial support force to the particle stent in an expanded state.

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