Stent weaving method, stent and stent delivery device

Abstract

The present disclosure provides a stent weaving method, a stent and a stent delivery device. At least two rows of hole positions without positioning piles are arranged on a columnar mandrel. A wire is used to pass through the bottom of a positioning pile and then to be bent up and down to pass through the positioning pile. The wire passes through two rows of hole positions without positioning piles and then passes through the lower positioning pile. The wire is wound on the positioning pile on the columnar mandrel to weave a stent with different flexibility in different regions. The flexibility of the woven mesh formed by the positions across the hole positions without positioning piles is higher, and the flexibility of the woven mesh at other positions is lower. The flexibility of the whole woven mesh is moderate, which prevents the stent from breaking during use and reduces the difficulty of loading and releasing the stent.

Description

Scaffold weaving method, scaffold and scaffold conveyor Technical Field

[0001] This disclosure relates to the field of medical device technology, and in particular to stent weaving methods, stents, and stent delivery devices. Background Technology

[0002] In the medical field, endoluminal prostheses are widely used for implantation into blood vessels, bile ducts, or other similar lumens within organisms. These prostheses, commonly referred to as stents, are used to maintain, open, or expand lumens or isolate lesions. Within tortuous lumens, stents that conform to the tortuous structure of the luminal space are needed to minimize adverse effects on the lumen while achieving therapeutic function. In both vascular and non-vascular applications, most sites requiring stent implantation exhibit tortuous or repetitive bending deformation. Existing stents suffer from the following problems: insufficient flexibility leading to stent breakage, stent port damage to the lumen, and stent occlusion or kinking. Highly flexible stents, on the other hand, present difficulties in loading and deployment, and the loading and deployment process is prone to problems such as excessive force, stent breakage, inaccurate positioning, and stent occlusion. Summary of the Invention

[0003] The purpose of this disclosure is to provide a stent weaving method, a stent, and a stent conveyor to solve the problem that insufficient or excessive flexibility of stents in the prior art affects the stent's performance.

[0004] The embodiments of this disclosure adopt the following technical solution: a bracket weaving method, which uses a columnar mandrel. The columnar mandrel has holes arranged in rows and columns at the intersection of its length dividing line and circumferential dividing line. The length dividing line is arranged along the length direction of the columnar mandrel, and the circumferential dividing line is arranged along the circumference of the columnar mandrel. The holes in adjacent rows are staggered. A positioning post protruding from the outer surface of the columnar mandrel is detachably provided in each hole. At least two columns of holes are arranged in a row without positioning posts, and positioning posts are provided at both ends of the holes in one of the columns without positioning posts.

[0005] Using any one of the positioning stakes as a reference point as the starting point, the wire is made to go around the bottom of the positioning stake and then bend up and down to go around the positioning stake. The wire crosses two rows of holes without positioning stakes and then goes around the next positioning stake. The wire is woven together on the columnar mandrel to form a mesh that includes a combination of diamond and circular structures.

[0006] In some embodiments, the following steps are included:

[0007] Step 1: Make the wire obliquely upward from the bottom of the first reference positioning pile in the first row of positioning piles corresponding to one end of the columnar mandrel, and make the wire obliquely downward from the upper part of the second reference positioning pile in the second row of positioning piles above the first row of positioning piles, with the second reference positioning pile close to the first reference positioning pile;

[0008] Step 2: Repeat Step 1 by moving the wire up and down between the first and second row of positioning posts until there is no corresponding positioning post to bypass in the second row. Then, move the wire diagonally upward across the two rows of holes and then diagonally downward around the positioning post in the fourth row. Next, move the wire diagonally upward around the bottom of one of the positioning posts in the third row. Continue winding the wire up and down between the third and fourth row of positioning posts in the same manner as in Step 1.

[0009] Step 3: Continue weaving the wire upwards along the length of the cylindrical mandrel until it reaches one of the last row of positioning posts at the other end of the mandrel. Then, the wire is wound diagonally downwards from the top of that positioning post to one of the positioning posts in the second-to-last row, where it crosses and wraps with the existing wire on that post. Finally, the wire is wound diagonally upwards from the bottom of that post to another positioning post in the last row. Repeat this back-and-forth, crisscrossing motion from the last row of positioning posts to the second-to-last row of positioning posts.

[0010] Step 4: Continue to weave the wire downwards along the length of the cylindrical mandrel, in the reverse direction of the winding method used in Step 1 and Step 2, crossing and weaving it with the existing wire until the wire wraps back to the first row of positioning stakes;

[0011] Step 5: Separate the positioning stakes to obtain the woven net.

[0012] In some embodiments, in step four, when the wire crosses downward across a hole where no positioning stake is provided, it intersects with the wire corresponding to the hole.

[0013] In some embodiments, in step three, the wire winds upward along the length of the columnar mandrel to the last row of positioning posts at the other end of the columnar mandrel. The row of positioning posts corresponds to the last row of holes on the columnar mandrel, and the row of holes corresponds to the odd-numbered row of holes on the columnar mandrel.

[0014] In some embodiments, the wires intersect at the positioning stakes to form a circular structure; the wires also intersect at four adjacent positioning stakes in three adjacent rows to form a rhomboid structure.

[0015] In some embodiments, in step five, the woven mesh on the columnar mandrel is heat-set before the positioning stake is separated.

[0016] This disclosure also provides a support, which is prepared by the above-described support weaving method, wherein the wire is constructed as a tough wire.

[0017] In some embodiments, the support is provided with a coating, which is a transparent film made of one of the following materials:

[0018] A transparent film made of expanded polytetrafluoroethylene; or a transparent film made of polyurethane; the film covering at least one end of the support.

[0019] In some embodiments, the wires form the same braided pattern on adjacent rows of positioning posts.

[0020] This disclosure also provides a support conveyor for conveying the aforementioned support; the support conveyor includes at least a tail end connector, a dual-cavity support tube, an outer tube connector, an outer tube, a mandrel tube, a conical head, and a rear release device. The tail end connector is connected to one end of the dual-cavity support tube, and the other end of the dual-cavity support tube is connected to one end of the outer tube via the outer tube connector. The other end of the outer tube is detachably connected to the conical head. The mandrel tube is installed in one of the cavities of the dual-cavity support tube. The rear release device includes a limiter, a pull handle, and a deploying wire. The retainer is disposed at one end of the mandrel tube near the conical head. The deploying wire passes through the pull handle disposed at the tail end connector into the other cavity of the dual-cavity support tube and extends to the conical head. The deploying wire cooperates with the limiter to keep the support in a non-folded state fixed to the mandrel tube.

[0021] In some embodiments, the retainer includes a retaining ring and a retaining coil. The retaining ring is secured to the outer circumferential surface of the mandrel tube, and a gap is formed between the retaining ring and the outer circumferential surface of the mandrel tube. One end of the retaining coil passes through the gap, and the retaining coil forms two corresponding loops on both sides of the retaining ring. One end of the retaining coil passes through a rhomboid or circular structure on the bracket. The unfolding wire passes through the two loops of the retaining coil.

[0022] In some embodiments, the end of the bracket near the dual-cavity support tube abuts against the end of the outer cavity support tube.

[0023] In some embodiments, the conical head is provided with a wire unfolding slot.

[0024] In some embodiments, the outer tube connector is provided with at least an outer tube flushing port, which is connected to the outer tube.

[0025] The beneficial effects of the embodiments disclosed herein are as follows:

[0026] The columnar mandrel has at least two rows of holes without positioning posts. A wire is wound around one of the positioning posts, then bends up and down repeatedly to bypass it. Simultaneously, the wire crosses two rows of holes without positioning posts before passing the next post, creating a woven mesh on the mandrel that combines diamond and circular structures. The mesh formed at the locations crossing the holes without positioning posts has higher flexibility, while the mesh at other locations has lower flexibility, resulting in a moderate overall flexibility. This prevents the risk of breakage during use and reduces the difficulty of loading and unloading the support. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 is a schematic diagram of the developed structure of the columnar mandrel of this disclosure (without the positioning stake installed);

[0029] Figure 2 is a schematic diagram of the developed structure of the cylindrical mandrel of this disclosure (with positioning stakes installed);

[0030] Figure 3 is a schematic diagram of the structure of the wire of this disclosure when it is braided from the bottom end of the columnar mandrel;

[0031] Figure 4 is a schematic view of the structure of the wire of this disclosure when it is braided to the last row of holes and begins to be hooked back; and a partial enlargement thereof.

[0032] Figure 5 is a schematic diagram of the structure after the braiding is reversed from the top of the columnar mandrel in this disclosure;

[0033] Figure 6 is a schematic diagram of the structure after the wire braiding of this disclosure is completed;

[0034] Figure 7 is a schematic diagram of the structure of the web formed by weaving according to the present disclosure;

[0035] Figure 8 is a structural schematic diagram of the support conveyor of this disclosure;

[0036] Figure 9 is a schematic diagram of another structure of the support conveyor disclosed in this invention;

[0037] Figure 10 is a schematic diagram of the structure when the developing wire of this disclosure is fully inserted into the developing wire slot;

[0038] Figure 11 is a schematic diagram of the structure when the unfolded yarn passes through two loops of the polyester thread;

[0039] Figure 12 is a schematic diagram of the structure when the end of the unfolded yarn detaches from one of the loops of the polyester yarn;

[0040] Figure 13 is a schematic diagram of the structure when the end of the unfolded yarn of this disclosure is separated from the polyester thread;

[0041] Figure 14 shows the state of the support on the mandrel tube after the end of the unfolded yarn detaches from the polyester yarn.

[0042] Reference numerals: 1-conical head, 101-developing wire slot, 102-rinsing tank, 2-limiter, 201-polyester wire, 202-fixing ring, 3-outer tube, 4-outer tube connector, 401-side tube, 402-rinsing port, 5-double-cavity support tube, 6-developing wire, 7-pull handle, 8-tail connector, 9-mandrel tube, 100-conveyor, 200-support, 300-column mandrel, 301-hole position, 302-positioning stake, 400 wire, L1-first row of holes, L2-second row of holes, Ln-last row of holes, Ln-1-second to last row of holes. Detailed Implementation

[0043] Various embodiments and features of this disclosure are described herein with reference to the accompanying drawings.

[0044] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this disclosure will be apparent to those skilled in the art.

[0045] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present disclosure and, together with the general description of the disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the disclosure.

[0046] These and other features of this disclosure will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0047] It should also be understood that although this disclosure has been described with reference to some specific examples, many other equivalent forms of this disclosure can be definitively implemented by those skilled in the art, which have the features of the claims and are therefore within the scope of protection defined herein.

[0048] The above and other aspects, features and advantages of this disclosure will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0049] Specific embodiments of this disclosure are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this disclosure, which may be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure this disclosure. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely to serve as the basis and representative basis for the claims to teach those skilled in the art to use this disclosure in a variety of substantially any suitable detailed structures.

[0050] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in still another embodiment,” all of which may refer to one or more of the same or different embodiments according to this disclosure.

[0051] To address the problems of insufficient flexibility in existing stents leading to breakage, deformation, or damage to the lumen, and excessive flexibility causing difficulties in loading and unloading, this disclosure provides a stent weaving method. As shown in Figure 1, this method uses a cylindrical mandrel 300. In various embodiments, the shape of the cylindrical mandrel is designed according to the needs of the stent, including but not limited to cylinders, elliptical cylinders, polygonal prisms, and other cylindrical shapes that can be constructed into a mandrel. In most cases, a cylindrical mandrel is chosen. The invention will be exemplified below using a cylindrical mandrel as an example. The cylindrical mandrel 300 has holes 301 arranged in rows and columns at the intersection of its length dividing line and circumferential dividing line. The length dividing line is arranged along the length direction of the cylindrical mandrel 300, and the circumferential dividing line is arranged along the circumference of the cylindrical mandrel 300. Specifically, the length dividing line is a ring around the circumference of the cylindrical mandrel 300, and the circumferential dividing line is a straight line along the length direction of the cylindrical mandrel 300. The spacing between the length dividing lines may be equal or unequal; the spacing between the circumferential dividing lines may be equal or unequal. The holes 301 corresponding to adjacent rows are staggered (the holes in adjacent columns are also staggered), that is, not all intersections of the length dividing lines and the circumferential dividing lines have holes. From the perspective of the row arrangement of holes, a hole can be set at every other intersection of a length dividing line and a circumferential dividing line, and the intersections of the holes in two adjacent rows are distributed on the holes in different columns.

[0052] As shown in Figures 1 and 2, the cylindrical mandrel 300 is used as an example for illustration. Positioning posts 302, protruding from the outer surface of the cylindrical mandrel 300, are detachably installed in the holes on the cylindrical mandrel 300. That is, one end of the positioning post 302 is detachably installed in the hole, and the other end extends as a free end away from the outer surface of the cylindrical mandrel 300. At least two rows of holes are not equipped with positioning posts; positioning posts are installed at both ends of the holes in one row of holes, with the positions of these positioning posts corresponding to the first and last rows of holes. The purpose of not installing positioning posts in the holes is to allow the woven mesh at these locations to have relatively high flexibility, thereby improving the overall flexibility of the mesh, i.e., the support structure.

[0053] Taking any one of the positioning stakes as the reference point as the starting point, the wire 400 is made to go around the positioning stake from the bottom and then bend up and down to go around the positioning stake. The wire 400 crosses two rows of holes without positioning stakes (and crosses two columns of holes at the same time) and then goes around the next positioning stake, so that the wire 400 is woven on the columnar mandrel 300 to form a mesh that includes a combination of diamond and circular structures.

[0054] In this weaving method, at least two rows of holes without positioning posts are set on the columnar mandrel 300. Wire 400 is used to wound around one of the positioning posts from its bottom, then repeatedly bent up and down to bypass the post. Simultaneously, wire 400 crosses two rows of holes without positioning posts before passing the next post, causing the wire 400 to be woven crosswise on the columnar mandrel 300 to form a mesh combining diamond and circular structures. The mesh formed at the locations crossing the holes without positioning posts has higher flexibility, while the mesh at other locations has lower flexibility, resulting in a moderate overall flexibility. This innovative weaving method achieves excellent bending resistance, flexural strength, and flexibility, preventing the risk of breakage during use and reducing the difficulty of loading and unloading the support.

[0055] In some embodiments, as shown in Figures 3-7, the weaving method includes the following steps:

[0056] Step 1: Starting from one end of the cylindrical mandrel, wire 400 is wound diagonally upwards around the bottom of the first reference positioning post in the first row of positioning posts. For clarity, the end from which wire 400 begins to wind around the cylindrical mandrel is the bottom end of the mandrel. After winding around the first reference positioning post, wire 400 is wound diagonally downwards around the second reference positioning post in the second row of positioning posts, which is immediately above and adjacent to the first row of positioning posts. The second reference positioning post is the one closest to the first reference positioning post in the second row of positioning posts.

[0057] Step Two: Repeat the winding pattern of wire 400 in Step One, moving it up and down between the first and second row positioning posts, until there are no corresponding positioning posts to bypass in the second row. Then, move wire 400 diagonally upwards across two rows of holes (including one hole in the second row and one hole in the third row), and then diagonally downwards around a positioning post in the fourth row. Finally, move wire 400 diagonally upwards around one of the positioning posts in the third row from its bottom. The number of rows of holes crossed by wire 400 depends on the number of rows of holes without positioning posts. Continue winding wire 400 up and down between the third and fourth row positioning posts in the same manner as in Step One. At this point, the shape formed by wire 400 between the first and second row positioning posts resembles a sine curve (except for the shape formed by wire 400 in holes without positioning posts), and the positions of the positioning posts correspond to the peaks and troughs of the sine curve. Similarly, the movement shape of wire 400 between the third and fourth row of positioning stakes is similar to the shape of a sine curve (except for the shape formed by wire 400 at the hole where no positioning stake is set), and the peak and trough positions of the two sine curves are the same.

[0058] Step 3: Continue braiding wire 400 upwards along the length of the cylindrical mandrel, following the same routing method as in Step 2. After wire 400 reaches one of the last row of positioning posts at the other end (top) of the cylindrical mandrel, wire 400 diagonally wraps downwards from the top of that positioning post to one of the positioning posts in the second-to-last row (the row closest to the last row). Wire 400 then crosses and wraps with the existing wire 400 on that positioning post before diagonally winding upwards from the bottom of that positioning post to another positioning post in the last row. The "crossing and wrapping" here refers to the following: assuming the wires 400 on either side of one of the positioning posts in the second-to-last row are the first and second segments of wire 400 respectively, the wire 400 winding from the last row to that positioning post first presses onto the first segment of wire 400, then passes through the bottom of the second segment of wire, meaning it is pressed down by the second segment of wire, and then wraps around the positioning post from the bottom. Then, make the wires move up and down, hooking and crisscrossing from the last row of positioning posts to the second-to-last row of positioning posts.

[0059] Step 4: Continue weaving the wire downwards along the length of the cylindrical mandrel, in the reverse direction of the winding method used in Steps 1 and 2, crossing and weaving it with the existing wires until the wire returns to the first row of positioning posts. Then, bend the wire upwards and wrap it around to form a closed loop with the subsequent wires (Figure 6). The shape formed by the wire hooking downwards from the top of the cylindrical mandrel onto the adjacent rows of positioning posts can be described as resembling a cosine curve (except for the shape formed at holes where no positioning posts are installed). The peak of this cosine curve corresponds to the trough of the sine curve formed by the wire on the two rows of positioning posts, and the trough of the cosine curve corresponds to the peak of the aforementioned sine curve. Similarly, the positioning posts are located at the peaks and troughs of the cosine curve. At this point, the area enclosed by the troughs of the sine curve, the peaks of the cosine curve, and the adjacent intersections of the sine and cosine curves in the three adjacent rows of positioning posts forms a diamond-shaped woven structure; the wires cross at the positioning posts to form a circular structure.

[0060] Step 5: Separate the positioning stakes from the columnar mandrel to obtain a woven organic whole, which serves as a mesh. Remove the mesh from the columnar mandrel; the resulting mesh is the support frame, which can be easily bent in three-dimensional space without breaking.

[0061] In some embodiments, in step four, when the wire crosses downwards across a hole where no positioning stake is provided, it intersects with the wire corresponding to the hole. Specifically, when the wire is bent downwards to form a shape, at least two inclined wires have been woven at the position where no positioning stake is provided. When the wire is bent downwards from the columnar core axis to cross this position, it first presses over one of the inclined wires and then passes through the bottom of the other inclined wire, that is, it is pressed down by the other inclined wire, thereby forming a cross-weave of wires.

[0062] In some embodiments, in step three, the wire is wound upward along the length of the columnar mandrel to the last row of positioning posts at the other end of the columnar mandrel. The row of positioning posts corresponds to the last row of holes on the columnar mandrel. The row of holes corresponds to the odd-numbered row of holes on the columnar mandrel. Positioning posts are detachably installed in all the holes corresponding to the row of holes.

[0063] In some embodiments, in step five, the woven mesh on the columnar mandrel is heat-set, for example, annealed, before the positioning stake is separated.

[0064] This disclosure also provides a stent 200 manufactured using the aforementioned stent weaving method. The filament is constructed from a tough filament, such as a filament made of metal or a filament made of a nickel-titanium alloy with superelasticity and shape memory function. During use, doctors may make appropriate adjustments based on the stent's characteristics, such as adding coatings, medications, or even films to the stent, depending on the patient's specific disease type. Furthermore, the weaving pattern formed on adjacent rows of positioning posts is identical. The stent also features radiopaque markers for indicating the key contour positions of the stent within the body.

[0065] In some embodiments, the support is covered with a film, which is made of an ultra-thin, transparent material such as eFTFE (expanded polytetrafluoroethylene) or PU (polyurethane). The film covers at least one end of the support. Reinforcing ribs are provided at the edge of the film-covered support, so that the edge of the ultra-thin film forms a whole under stress, and the film edge is fixed to prevent damage during loading and unloading. Specifically, a piece of ePTFE (a microporous membrane formed by expanding and stretching polytetrafluoroethylene) is rolled into a thin rope and folded into a double strand. The rope is placed between the inner and outer layers of the support, and the folded part of the support forms a semi-circle or ring (knotted near the fold) and is placed at the edge of the film. The rest of the rope faces the other end of the support. The rope and the film are made of the same material, which easily achieves material fusion. The rope fused within the film acts as a reinforcing rib. Therefore, when using an ultra-thin film, the above-mentioned reinforcing ribs can prevent the film-covered support from breaking under stress during loading and unloading. Meanwhile, the ultra-thin lining ensures a small compression cross-sectional area for the support, reducing the load cross-sectional area requirements of the conveyor. The lining section is designed according to the lining support scheme, with the lining edge covering a small section of the support structure. For controllable diameter lining supports and controllable diameter lining supports with bare sections, a smaller diameter lining cylinder is fitted over the lining section to constrain the outer diameter of the support. If necessary, the diameter of the support at this point is expanded by a balloon. The circumferential stretching generated by the lining cylinder material during high-pressure expansion reduces the need to control the support diameter, thus achieving diameter adjustment.

[0066] The aforementioned stents are moderately flexible, and after implantation, they can conform to the tortuous anatomical structure, maintain long-term patency of the lumen, and reduce the side effects of stent implantation.

[0067] Furthermore, the delivery system needs to be as small as possible to achieve minimally invasive treatment when the stent is delivered into the lumen. Stent loading and release typically involve relative movement between the stent and the delivery tubing. During loading and release, friction exists between the stent and the delivery tubing, which can easily lead to stent accumulation during loading, causing loading difficulties, and excessive release force during release, resulting in displacement, bouncing, or undesirable placement. Currently, stents designed for easy loading and release have axial fixing connections. However, these connections affect the stent's bending performance, resulting in poor bending performance or a clear directional requirement for bending. Covered stents require a thicker covering layer to ensure stent integrity during loading and release. A thicker covering, due to the membrane's inherent resistance, can severely affect the stent's bending performance. Increased membrane thickness directly increases the compressible volume of the covered stent, significantly increasing the required delivery system size and leading to excessive access trauma.

[0068] To address the requirements of stents simultaneously meeting the demands of arbitrary spatial bending, precise release, simple operation, and minimally invasive access, existing technologies constrain the stent to prevent displacement during its exit from the delivery tube. After passing through the tube, the constraint is released, achieving precise release.

[0069] Patent CN105943215B discloses a covered stent delivery and distal positioning and release system. This system uses a winding system and polyester thread to fix the stent and achieves distal-to-proximal positioning and release, improving positioning accuracy. Patent CN102961198B discloses a covered stent delivery device that uses a positioning post to lock the front section of the stent and then releases it to ensure the stent is placed in the intended surgical position. Patent CN106580530B discloses a precisely positioned distal-to-proximal post-release covered stent delivery system and method. By fixing and releasing the proximal and distal ends of the stent, it avoids axial shortening after stent loading and prevents inaccurate distal release from occluding branch vessels near the distal rupture site.

[0070] The existing publicly available stent delivery technology for precise release after constraint is mainly applicable to large aortic stents. If used as a delivery device for small and medium-sized lumbar stents, it will have the following shortcomings: 1. The constraint structure of the stent delivery device is complex, making implementation difficult, and requiring specialized equipment to bind the stent; 2. The constraint of the stent delivery device is large, resulting in a large stent release force or requiring the selection of a larger delivery tube, which is not conducive to reducing access requirements.

[0071] To address the aforementioned issues, this disclosure also provides a support conveyor. In this disclosure, the term "proximal end" of the conveying system refers to the end relatively close to the operator, and "distal end" refers to the end relatively far from the operator. This support conveyor 100 conveys the aforementioned support 200. As shown in Figures 8-14, the support conveyor 100 includes at least a tail connector 8, a double-lumen support tube 5, an outer tube connector 4, an outer tube 3, a mandrel tube 9, a conical head, and a small rear release device. The rear release device includes a limiter 2, a pull wire handle 7, and a deploying wire 6. The tail connector 8 is connected to one end of the double-lumen support tube 5. The tail connector 8 is a Y-type connector, meaning it has two ports: a side port for connecting the deploying wire 6 in the rear release device (the deploying wire 6 can be made of metal wire); and an axial port for connecting the mandrel tube 9. This effectively prevents the rear release pull wire from moving during transportation and feeding, thus avoiding rear release failure. The other end of the double-lumen support tube 5 is connected to one end of the outer tube 3 via the outer tube connector 4, and the mandrel tube 9 passes through one of the lumens of the double-lumen support tube 5. The mandrel tube 9 is a single-lumen tube, and its other end is axially connected to one end of the conical head. The outer tube connector 4 can be directly equipped with the side tube 401 as shown in Figure 8, or as shown in Figure 9, the outer tube connector 4 is equipped with a hemostatic valve and a flushing port 402. The flushing port 402 is connected to the outer tube connector 4 via the side tube 401, and the flushing port is connected to the outer tube. The end of the outer tube connector 4 is also equipped with a locking device. The outer tube can only be retracted to release the stent 200 by opening the locking device, which is used to prevent the stent from being released prematurely during transportation and delivery. In addition, the end of the outer tube connector 4 is equipped with a knob, which can be tightened to lock the relative position of the outer tube and the double-lumen support tube to prevent the stent system from being released accidentally. The other lumen of the double-lumen support tube is used to pass through the unfolding wire 6. The two lumens of the double-lumen support tube are arranged in parallel and are both linear lumens. The other end of the outer tube is detachably connected to the conical head, which has a rinsing groove 102. The conical head should fit snugly against the outer tube, and the transition between the two should be smooth and not scratchy. The conical head is a cone-shaped body made of soft polymer material, with a through hole in the central axis serving as the channel for the spreading wire 6; it also has a slot 101 for receiving the head end of the spreading wire 6. The retainer in the release device is located at the distal end of the mandrel tube 9, that is, near the conical head. The spreading wire 6 passes through the pull handle 7 located at the tail end connector into the other cavity of the double-cavity support tube and extends to the conical head. This pull handle is interference-fitted onto the side branch port. The conical head, mandrel tube 9, and tail end connector 8, when connected, form a connected cavity as a receiving channel for the spreading wire 6, ensuring that the support conveyor 100 can reach the target position under the guidance of the spreading wire 6 and that the receiving channel can be rinsed through the axial port of the tail end connector. The unfolding wire 6 cooperates with the limiter 2 to keep the bracket in a non-folded state and fixed to the mandrel tube. The conveyor only fixes one end of the bracket, and the end of the bracket near the double-cavity support tube abuts against the end of the outer cavity support tube, so that the volume of the rear release device and the bracket overlapping in the conveying system is minimized.

[0072] This delivery system, through the aforementioned small post-release device, enables the loading and release of highly compliant stents without stent stacking or displacement, with minimal release force and precise release. The loading area of ​​the delivery system itself has a small cross-sectional area, approaching the compressible cross-sectional area of ​​the stent. This delivery system utilizes a combination of a spreading wire 6 and a limiter 2 to secure the stent, resulting in a simple and easily implemented design. The delivery system is compact, safe, and reliable, effectively reducing the cross-sectional area of ​​the stent loading area and achieving the goal of minimally invasive flexible stent delivery. This stent delivery system solves the problem of minimally invasive delivery of highly compliant stents, and the small delivery system reduces access requirements and damage.

[0073] In some embodiments, the fixator includes a fixing ring 202 and a fixing coil. The fixing coil can be made of flexible polyester thread 201 or other materials. Both the polyester thread 201 and the unfolding wire 6 can be made very thin, occupying a small volume and ensuring the minimally invasive nature of the delivery system. At the same time, the structure is very simple; pulling the unfolding wire backward achieves 100% separation of the delivery system from the support, ensuring safety and reliability. The fixing ring 202 is secured to the outer circumferential surface of the mandrel tube, forming a gap between the fixing ring 202 and the outer circumferential surface of the mandrel tube. One end of the fixing coil passes through the gap, and the fixing coil forms two corresponding loops on both sides of the fixing ring 202. One end of the fixing coil passes through the diamond-shaped or circular structure on the support, and then the unfolding wire passes through the two loops of the fixing coil to fix one end of the support.

[0074] During use, after loosening the protective device during bracket release, the outer tube is pulled back to unfold the bracket. Once fully unfolded, the pull handle is loosened and pulled back to disengage the unfolding thread end from the loop formed by the polyester thread 201, thus detaching the bracket from the conveying system and fully releasing it. The front end of the bracket remains fixed relative to the front end of the conveying system, maintaining an axial single-layer state during loading and release within the conveying system. This avoids the problem of brackets easily stacking due to the lack of axial support during loading and release, which can lead to difficulties in loading and release, excessively large conveying system dimensions, and inaccurate release. In particular, the precise release of brackets has long been a challenge in the industry due to their compressed length being significantly longer than their unfolded length. While commonly the front end of the bracket is fixed to the conveying system, maintaining its position relative to the system during release, this conveyor, positioned by the front end, enables precise bracket release.

[0075] The foregoing has provided a detailed description of several embodiments of this disclosure. However, this disclosure is not limited to these specific embodiments. Those skilled in the art can make various variations and modifications based on the concept of this disclosure, and all such variations and modifications should fall within the scope of protection claimed by this disclosure.

Claims

1. A method for weaving a support frame, wherein the method uses a columnar mandrel, characterized in that, The cylindrical mandrel has holes arranged in rows and columns at the intersection of its length dividing line and circumferential dividing line. The length dividing line is arranged along the length of the cylindrical mandrel, and the circumferential dividing line is arranged along the circumference of the cylindrical mandrel. The holes in adjacent rows are staggered. Each hole has a detachable positioning post protruding from the outer surface of the cylindrical mandrel. At least two rows of holes are not equipped with positioning posts, while the holes at both ends of one row of holes are equipped with positioning posts. Using any one of the positioning posts as a reference point, the wire is wound around the bottom of the positioning post. Then, the wire bends back and forth, bypassing the positioning stakes. The wire crosses two rows of holes without positioning stakes before bypassing the next positioning stake. The wire is then woven across the columnar mandrel to form a mesh consisting of a combination of diamond and circular structures. The method includes the following steps: Step 1: The wire is diagonally upwards from the bottom of the first reference positioning stake in the first row of positioning stakes corresponding to one end of the columnar mandrel, and diagonally downwards from the top of the second reference positioning stake in the second row of positioning stakes above the first row of positioning stakes, with the second reference positioning stake adjacent to the first reference positioning stake. Step 1: Repeat Step 2: Move the wire up and down between the first and second row of positioning posts until there is no corresponding positioning post to bypass in the second row. Then, move the wire diagonally upwards across two rows of holes and then diagonally downwards around the positioning post in the fourth row. Next, move the wire diagonally upwards around the bottom of one of the positioning posts in the third row. Continue winding the wire up and down between the third and fourth row positioning posts in the same manner as in Step 1. Step 3: Continue weaving the wire upwards along the length of the cylindrical mandrel until the wire reaches the last row of positioning posts at the other end of the cylindrical mandrel. After one of the positioning posts, the wire is wound diagonally downwards from the top of the positioning post to one of the positioning posts in the second-to-last row, and the wire is intertwined with the existing wire on the positioning post before being wound diagonally upwards from the bottom of the positioning post to another positioning post in the last row; the wire is repeatedly hooked and intertwined from the last row of positioning posts to the second-to-last row of positioning posts; Step 4: the wire is continuously wound downwards along the length of the columnar mandrel in the opposite direction to the winding method of Step 1 and Step 2, intertwining with the existing wire, until the wire is wound back to the first row of positioning posts; Step 5: the positioning posts are separated to obtain the woven net.

2. The bracing method according to claim 1, characterized in that, In step four, when the wire crosses downward across a hole where no positioning stake is set, it intersects with the wire corresponding to the hole.

3. The bracing method according to claim 1, characterized in that, In step three, the wire is wound upwards along the length of the cylindrical mandrel to the last row of positioning posts at the other end of the cylindrical mandrel. This row of positioning posts corresponds to the last row of holes on the cylindrical mandrel, and this row of holes corresponds to the odd-numbered row of holes on the cylindrical mandrel.

4. The bracing method according to claim 1, characterized in that, The wires intersect at the positioning stakes to form a circular structure; the wires also intersect at the four adjacent positioning stakes in three adjacent rows to form a rhomboid structure.

5. The bracing method according to claim 1, characterized in that, In step five, the woven mesh on the columnar mandrel is heat-set before the positioning stake is separated.

6. A stent, characterized in that, The support is prepared by any one of the support braiding methods described in claims 1-5, and the wire is constructed as a tough wire.

7. The stent according to claim 6, characterized in that, The support is covered with a film, which is a transparent film made of one of the following materials: a transparent film made of expanded polytetrafluoroethylene; or a transparent film made of polyurethane; the film covers at least one end of the support.

8. The bracket according to claim 6, characterized in that, The wires form identical weave patterns on adjacent rows of positioning stakes.

9. A stent system comprising a stent conveyor and the stent according to claim 7 or 8, characterized in that, The support conveyor transports the support; the support conveyor includes at least a tail end connector, a double-cavity support tube, an outer tube connector, an outer tube, a mandrel tube, a conical head, and a rear release device. The tail end connector is connected to one end of the double-cavity support tube, and the other end of the double-cavity support tube is connected to one end of the outer tube through the outer tube connector. The other end of the outer tube is detachably connected to the conical head. The mandrel tube is installed in one of the cavities of the double-cavity support tube. The rear release device includes a retainer, a pull handle, and a deploying wire. The retainer is located at the end of the mandrel tube near the conical head. The deploying wire passes through the pull handle located at the tail end connector into the other cavity of the double-cavity support tube and extends to the conical head. The deploying wire cooperates with the retainer to keep the support in a non-folded state fixed to the mandrel tube.

10. The support system according to claim 9, characterized in that, The fixture includes a fixing ring and a fixing coil. The fixing ring is secured to the outer circumferential surface of the mandrel tube. A gap is formed between the fixing ring and the outer circumferential surface of the mandrel tube. One end of the fixing coil passes through the gap. The fixing coil forms two corresponding loops on both sides of the fixing ring. One end of the fixing coil passes through the rhomboid or circular structure on the bracket. The unfolding wire passes through the two loops of the fixing coil.

11. The support system according to claim 9, characterized in that, The end of the bracket near the double-lumen support tube abuts against the end of the double-lumen support tube.

12. The support system according to claim 9, characterized in that, The conical head is provided with a wire unfolding slot.

13. The support system according to claim 9, characterized in that, The outer tube connector is provided with at least one outer tube flushing port, which is connected to the outer tube.

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