Anti-backflow and anti-displacement woven ureter covered stent

Abstract

The anti-backflow and anti-displacement woven ureter covered stent comprises a stent body formed by splicing a plurality of metal wire woven units in the circumferential direction, and the stent body sequentially comprises a first anti-displacement section, a radial supporting section, an anti-backflow section, a bundling extension section and a second anti-displacement section from the far end to the near end. The diameter of the first anti-displacement section is gradually increased from the near end to the far end, the anti-backflow section is connected with the far end of the bundling extension section through a funnel-shaped structure, an anti-backflow structure is arranged at the funnel-shaped structure, and the second anti-displacement section is composed of a plurality of metal wire anchor hooks. Each metal wire weaving unit on the radial supporting section is composed of a plurality of circumferential wave sections and axial straight line sections which repeatedly appear in the axial direction, and every two adjacent metal wire weaving units on the radial supporting sections are spliced and fixed through first locking pieces locked on the axial straight line sections close to each other. The support has the advantages of being high in axial supporting capacity and radial supporting capacity, good in durability, and meanwhile good in backflow resistance and displacement prevention capacity.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of medical devices, and particularly relates to an anti-reflux and anti-migration braided ureteral covered stent. BACKGROUND

[0002] Ureteral stents are mainly used to relieve ureteral obstruction and promote postoperative ureteral healing. For ureteral stone surgery, a general ureteral stent can be used, but for patients with ureteral stenosis, a long-term indwelling ureteral stent is sometimes required. Reflux and migration are two major complications of traditional ureteral stents in clinical application. The traditional ureteral stent is designed as a two-way channel, which destroys the anti-reflux mechanism at the ureteral bladder opening. When the intravesical pressure rises (such as urination, coughing), urine will reflux to the renal pelvis, causing upper urinary tract infection, hydronephrosis, and even renal function damage. Studies have shown that the incidence of reflux of traditional ureteral stents can reach more than 50%, and is significantly related to ureteral stent-related symptoms. In addition, due to insufficient friction between the traditional ureteral stent and the ureteral wall, about 10%-30% of patients will experience stent migration or complete shedding, leading to drainage failure and the need for repositioning surgery. The risk is higher in children, patients with ureteral dilation, or patients with strenuous activities.

[0003] Ureteral stents can be mainly divided into polymer material stents and metal material stents. Polymer material stents include polyethylene (PE), silicone, polyurethane (PU), etc. Polymer material stents have the problems of easy encrustation, infection, and poor mechanical strength, and are generally implanted for a short time (within 6 months) in clinical practice. Metal material stents include composite metal material stents and inflatable metal stents. Composite metal material stents: Resonance stents are made of nickel-cobalt-chromium-molybdenum composite materials, which have strong tensile strength and corrosion resistance. Inflatable metal stents: Memokath-051 spiral stents are made of nickel-titanium alloy, which is soft before placement and expands and fixes after heating, with a retention time of up to 4 years, but has the disadvantage of easy migration. Uventa stents are made of nickel-titanium alloy and have a polytetrafluoroethylene surface that can reduce irritation symptoms and encrustation, but perform poorly in chronic ureteral obstruction. Alium large-diameter stents are made of nickel-titanium alloy and are covered with a polymeric material that prevents tissue ingrowth, and have acceptable results in treating chronic ureteral stenosis, but have the problem of reflux.

[0004] Although the metal material stent has better compression resistance than the polymer material stent, when facing the situation that both axial and radial support force of the stent are required to be higher (poor axial support force will cause the stent to shrink excessively in the axial direction when loaded into the conveyor, resulting in that the stent cannot be fully expanded after being released; poor radial support force will not be able to effectively expand the narrow section of the ureter), the stent body composed of a single helical wave-shaped metal wire still cannot meet the use requirements, and the stent body formed by the interlaced metal wires has sufficient axial and radial support force, but the interlaced part is prone to breakage or damage to the covering film due to wear between the wires. Therefore, it is necessary to design a new metal material stent which has better axial and radial support force, is not prone to wear and breakage, and has anti-reflux and anti-migration functions. SUMMARY

[0005] The present application provides an anti-reflux and anti-migration woven ureteral covering stent, which aims to overcome the above-mentioned deficiencies of the conventional metal material ureteral stent in the prior art.

[0006] The technical scheme for solving the above-mentioned technical problems is as follows: an anti-reflux and anti-migration woven ureteral covering stent, comprising a stent body composed of a plurality of metal wire weaving units spliced in the circumferential direction, wherein the stent body comprises, from the distal end to the proximal end, a first anti-migration section, a radial support section, an anti-reflux section, a bunching extension section and a second anti-migration section, a covering layer is arranged on the first anti-migration section and the radial support section, the radial support section is in a cylindrical shape, the diameter of the first anti-migration section gradually increases from the proximal end to the distal end, the anti-reflux section is connected to the distal end of the bunching extension section through a funnel-shaped structure, the funnel-shaped structure is provided with an anti-reflux structure, the second anti-migration section is composed of a plurality of metal wire anchors uniformly and spaced apart in the circumferential direction at the proximal end of the bunching extension section, each metal wire weaving unit on the radial support section is composed of a plurality of circumferential wave sections and axial straight sections which repeatedly appear in the axial direction, two adjacent circumferential wave sections in the axial direction are connected through the axial straight section, and two adjacent metal wire weaving units on the radial support section are spliced and fixed through a locking piece one locked on the axial straight sections close to each other, and a plurality of metal wires in the bunching extension section which are parallel to each other and close to each other are fixed into a bundle by a locking piece two.

[0007] On the basis of the above-mentioned technical scheme, the present application can also be improved as follows.

[0008] Further, each metal wire weaving unit is bent and woven from a metal wire.

[0009] The improved advantage lies in that each braiding unit is braided by one metal wire without cutting, which ensures good integrity and higher braiding efficiency. The multiple braiding units constituting the same stent body can be braided simultaneously, standby, and then assembled uniformly, which is high in production efficiency.

[0010] Further, both ends of the same metal wire constituting the metal wire braiding unit are located at the funnel-shaped structure and locked and fixed by the locking member three. The adjacent two metal wire braiding units are also spliced and fixed at the funnel-shaped structure by the locking member three.

[0011] The improved advantage lies in that the funnel-shaped structure is contracted to the center of the stent body, so that after being placed in the ureter, the funnel-shaped structure is basically not subjected to repeated compression of the ureter wall, and there is no repeated deformation and rebound, so that the risk of the two ends of the metal wire being fixed at the funnel-shaped structure and being separated from each other is small.

[0012] Further, each metal wire braiding unit has circumferentially adjacent circumferential wave segments, and the adjacent two circumferential wave segments are fixedly connected by the locking member one locked on the corresponding axial straight segment close to each other.

[0013] The improved advantage lies in that the same metal wire braiding unit has two circumferentially adjacent circumferential wave segments, that is, the same metal wire is first braided from bottom to top to form one half of the structure in the unit, and then folded back to be braided from top to bottom to form the other half of the structure, so that the two ends of the same metal wire can be close to each other and fixed to form a closed loop after folding back, and the integrity of the metal wire braiding unit is better.

[0014] Further, the metal wire of each metal wire braiding unit is bent into a circular arc shape and gradually turned outward at the first anti-displacement segment, and the adjacent two metal wire braiding units are spliced and fixed by the developing ring arranged at the intersection of the first anti-displacement segment and the radial support segment.

[0015] The improved advantage lies in that the gradually turned outward circular arc structure makes the diameter of the stent body gradually expand and increase, so that it can be clamped in the ureter and play a role in preventing displacement; the developing ring can display the position of the stent body placed in the ureter under X-ray irradiation, which is convenient for precise implantation.

[0016] Further, the metal wire of each metal wire braiding unit is bent into a double-stranded wire form to form a metal wire anchor hook at the second anti-displacement segment.

[0017] The improved wire is folded back to form a double wire, and then is bent to form the wire anchor hook, so that the hook tip of the anchor hook is the folded back end of the wire, the hook tip is smooth and has no sharp tip, and the double wire has better strength and can prevent displacement.

[0018] Further, the funnel-shaped structure is formed by a plurality of inclined wires which are spaced apart in the circumferential direction of the stent body and gradually converge towards the central axis of the stent body from the distal end to the proximal end.

[0019] The improved wire is folded back to form a double wire, and then is bent to form the wire anchor hook, so that the hook tip of the anchor hook is the folded back end of the wire, the hook tip is smooth and has no sharp tip, and the double wire has better strength and can prevent displacement.

[0020] Further, each of the inclined wires is connected to the proximal end of the radial support segment through the axial straight segment.

[0021] Further, the anti-reflux structure is composed of a plurality of valves arranged outside the funnel-shaped structure to form a valve for reflux, the distal end of the valve is fixedly connected to the thick end of the funnel-shaped structure, and the proximal end of each valve converges and closes at the thin end of the funnel-shaped structure.

[0022] The improved wire is folded back to form a double wire, and then is bent to form the wire anchor hook, so that the hook tip of the anchor hook is the folded back end of the wire, the hook tip is smooth and has no sharp tip, and the double wire has better strength and can prevent displacement.

[0023] Further, the number of the wire weaving units is three, the first locking member is a double-lumen tube, the second locking member is a six-lumen tube, and the hook tips of the wire anchor hooks are connected in series by a traction rope.

[0024] The improved wire is folded back to form a double wire, and then is bent to form the wire anchor hook, so that the hook tip of the anchor hook is the folded back end of the wire, the hook tip is smooth and has no sharp tip, and the double wire has better strength and can prevent displacement.

[0025] Compared with the prior art, the present application has the following advantages:

[0026] The ureteral covered stent provided by the application is formed by splicing and fixing a plurality of wire weaving units in the circumferential direction, and the circumferential wave section in the radial support section is locked and fixed in the circumferential direction by a locking piece. Compared with a stent body formed by a single spiral wave-shaped wire, the support capability in the axial and radial directions is significantly enhanced. Compared with a stent body formed by crossing wires, the problem of easy breakage or damage of the covering film due to wear between the wires at the intersection point does not exist, and the durability is better. Meanwhile, the plurality of locking pieces distributed on the radial support section form anti-skid protrusions on the stent body, which can appropriately increase the positioning effect of the stent in the ureter and reduce the risk of displacement.

[0027] In addition, the ureteral covered stent provided by the application has a first anti-displacement section at the distal end and a second anti-displacement section at the proximal end, and the two anti-displacement sections can better ensure that the stent does not displace or fall off after being placed, thereby avoiding possible drainage failure and secondary replacement. In addition, the stent is provided with an anti-reflux section at the proximal end of the radial support section, the anti-reflux section has a funnel-shaped structure that contracts toward the central axis of the stent body, the funnel-shaped structure is provided with an anti-reflux structure, and the anti-reflux section is separately provided from the radial support section, so that the anti-reflux section basically does not affect the anti-reflux effect of the anti-reflux structure due to changes in the radial pressure of the stent, and the performance is more stable.

[0028] Each wire weaving unit of the ureteral stent provided by the application can be independently made of a wire, the structure is relatively simple, laser cutting or other complex processes are not required, the cost is relatively low, and by controlling the length of the wire, the length of the circumferential bending section and the length of the axial support section, the length and diameter of the stent can be arbitrarily adjusted. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.

[0030] Figure 2 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure. Figure 1 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.

[0031] Figure 3 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure. Figure 1 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.

[0032] Figure 4 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure. Figure 1 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.

[0033] Figure 5 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure. Figure 1 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.

[0034] Figure 6 A front view of an anti-reflux and anti-displacement woven ureteral covered stent provided by the application is shown in the figure.Figure 1 Front view of the stent shown when placed horizontally;

[0035] Figure 7 For Figure 6 Sectional view of the stent shown, with locking member three;

[0036] Figure 8 For Figure 1 Axonometric view of the stent shown (each wire anchor is connected by a traction cord);

[0037] Figure 9 For Figure 1 Front view of one wire weaving unit of the stent shown (located at the rear side);

[0038] Figure 10 For Figure 9 Right view of the stent shown;

[0039] Figure 11 For Figure 9 Enlarged view of the circled portion C in the wire weaving unit shown;

[0040] Figure 12 For Figure 9 Schematic of wire bending and wire routing direction when weaving the wire weaving unit shown (black and red are only for convenience, in essence, different parts of the same wire, arrows are used to show the wire bending and routing direction);

[0041] Figure 13 For Figure 8 Schematic of the stent shown placed in the human body.

[0042] In the drawings, the components represented by each reference numeral are listed as follows:

[0043] 1. First anti-migration section; 2. Radial support section; 3. Anti-regurgitation section; 4. Bundle extension section; 5. Second anti-migration section; 6. Film covering layer; 7. Circumferential wavy section; 8. Axial straight section; 9. Locking member one; 10. Locking member two; 11. Locking member three; 12. Visualization ring; 13. Valve; 14. Traction cord. DETAILED DESCRIPTION

[0044] The technical solutions provided by the present application will be described in detail below with reference to the drawings and specific embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0045] In the description of the present application, if the terms of "upper", "lower", "left", "right", "top", "bottom", "inner", "outer" and the like indicating the orientation are used, the indicated orientation or position relationship is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0046] As shown in Figures 1 to 13 The present application provides an anti-reflux anti-migration woven ureteral covered stent, which comprises a stent body composed of a plurality of wire weaving units spliced in the circumferential direction, the stent body is sequentially provided with a first anti-migration section 1, a radial support section 2, an anti-reflux section 3, a bunching extension section 4 and a second anti-migration section 5 from the distal end to the proximal end, the first anti-migration section 1 and the radial support section 2 are both provided with a covering layer 6, the radial support section 2 is cylindrical, the first anti-migration section 1 gradually increases in diameter from the proximal end to the distal end, the anti-reflux section 3 is connected with the distal end of the bunching extension section 4 through a funnel-shaped structure, the funnel-shaped structure is provided with an anti-reflux structure, the second anti-migration section 5 is composed of a plurality of wire anchors uniformly and spaced apart in the circumferential direction at the proximal end of the bunching extension section 4, each wire weaving unit on the radial support section 2 is composed of a plurality of circumferential wave sections 7 and axial straight sections 8 which repeatedly appear in the axial direction, two adjacent circumferential wave sections 7 in the axial direction are connected through the axial straight section 8, and two adjacent wire weaving units on the radial support section 2 are spliced and fixed through a locking member I 9 locked on the axial straight section 8 close to each other, and a plurality of parallel and close metal wires in the bunching extension section 4 are fixed into a bundle by a locking member II 10.

[0047] It should be noted that the metal wires of each wire weaving unit of the above-mentioned ureteral covered stent provided by the present application are nickel-titanium alloy wires, which can be as thin as 0.02mm, and the nickel-titanium alloy wires have the characteristics of realizing deformation at different phase transition temperatures and have superelasticity. In the present application, the metal wires used to weave each wire weaving unit have the characteristic of softening at low temperature (preferably <5℃). The covering layer on the stent body mainly covers the first anti-migration section, the entire radial support section and the distal end region of the anti-reflux section, i.e. the covering layer is mainly distributed in the region of the stent body which is easy to contact with the inner wall of the ureter, the membrane layer blocks the growth of tissue on the inner wall of the ureter into the stent lumen, reduces the risk of restenosis and facilitates subsequent stent removal. The forming process of the covering layer can be dipping, spraying, laminating, hot melting and sewing, etc. The locking member I and the locking member II can be a metal multi-lumen tube or a silk thread with good biocompatibility, and the fixing method can be extrusion deformation and locking or binding fixation.

[0048] The radial support section of the ureter covered stent provided by the application mainly covers the ureter narrow section, and the plurality of circumferential wave sections are fixed through the locking member one on the circumference of the stent body, which can effectively improve the radial support force of the section, so as to achieve the purpose of mechanically expanding the ureter narrow section. When the stent needs to be taken out of the ureter, the stent body is softened through cooling treatment, and the circumferential wave section can be contracted to reduce the diameter of the stent, thereby facilitating the taking out.

[0049] In an embodiment of the present application, as shown in Figures 9-12 , each of the metal wire weaving units is bent and woven from one metal wire. Both ends of the same metal wire constituting the metal wire weaving unit are located at the funnel-shaped structure and are locked and fixed by the locking member three 11. Adjacent two metal wire weaving units are also spliced and fixed at the funnel-shaped structure by the locking member three 11, as shown in Figure 6 , 7 , 9, 11 and 12. Each of the metal wire weaving units has the circumferential wave sections 7 adjacent in the circumferential direction, and adjacent two circumferential wave sections 7 are fixedly connected by the locking member one 9 locked on the corresponding axial straight section 8 close to each other.

[0050] It should be noted that one metal wire is not cut off, but is bent and wired according to the bending mode shown in Figure 12 , and is locked and fixed by the locking member three 11 after meeting at the funnel-shaped structure. The locking member three can be a three-lumen tube. Two lumens of one three-lumen tube are used for respectively inserting and locking two ends of one metal wire weaving unit (as shown in Figure 10 , and the three-lumen tube is not shown), and the other lumen is used for the metal wire of the metal wire weaving unit to pass through when splicing with the adjacent metal wire weaving unit. Figure 10 One lumen of the locking member three 11 shown in the figure is penetrated by one metal wire of the metal wire editing unit shown in the figure, and the other two lumens of the locking member three are respectively inserted by two ends of the metal wire of the other metal wire weaving unit adjacent thereto (not shown in the figure).

[0051] In an embodiment of the present application, as shown in Figure 9 and Figure 10 , the metal wire of each metal wire weaving unit is bent into a circular arc shape at the first anti-displacement section 1 and gradually turned outward. In addition, as shown in Figure 1 and Figure 2 , adjacent two metal wire weaving units are spliced and fixed by the developing ring 12 arranged at the joint of the first anti-displacement section 1 and the radial support section 2.

[0052] It can be understood that, as shown in Figure 8As shown, after the three wire braiding units are spliced into the stent body, the first anti-displacement section is in the shape of a trumpet mouth and uniformly distributes three developing rings in the circumferential direction. The design of the trumpet mouth can not only prevent the stent from moving in the direction of the bladder, but also more effectively collect and drain urine.

[0053] In an embodiment of the present application, as shown in Figure 8 , Figure 9 As shown, the wire of each wire braiding unit is bent into a wire anchor hook in the form of a double-stranded wire at the second anti-displacement section 5.

[0054] It should be noted that, as shown in Figure 12 , in this embodiment, the wire anchor hook bent in the form of a double-stranded wire refers to that the wire extends obliquely downward from the funnel-shaped structure, then bends to extend vertically downward (used to form part of the bundle extension section), extends downward for a period of time, then bends to extend upward while continuing to extend downward, then turns around by 180 degrees and extends upward along the structure just bent (at this time the wire anchor hook has been formed), and then extends symmetrically in another direction obliquely upward to the tip of the funnel-shaped structure, and then extends upward to braid the radial support section.

[0055] In an embodiment of the present application, as shown in Figure 1 and Figure 2 , the funnel-shaped structure is surrounded by multiple inclined wires spaced apart in the circumferential direction of the stent body, and the inclined wires gradually converge to the central axis of the stent body from the distal end to the proximal end.

[0056] In other words, the funnel-shaped structure is in the shape of a tapered cylinder, which gradually shrinks from the distal end to the proximal end and shrinks to near the central axis of the stent body at the distal end of the bundle extension section, as can be seen from Figure 2 , the funnel-shaped structure is a frame composed of three inclined wires, the lower ends (proximal ends) of the three inclined wires extend downward after approaching each other, and the downward extension section is the bundle extension section. The upper part of the inclined surface of the funnel-shaped structure can have a film layer, but the film layer at this position should be in a relaxed state and not affect the opening and closing of the valve arranged thereon.

[0057] In an embodiment of the present application, each of the inclined wires is connected to the proximal end of the radial support section 2 through the axial straight section 8.

[0058] It should be noted that, as shown in Figure 1 , in addition to the funnel-shaped structure at the lower part, the anti-reflux section also has a cylindrical structure (with a film layer) arranged in the circumferential direction by several axial straight sections, which plays a certain buffering role and ensures that the radial support section does not affect the valve arranged on the funnel-shaped structure at the lower part when it is compressed and deformed.

[0059] In one embodiment of the present application, the anti-reflux structure is composed of multiple flaps of valve 13 arranged outside the funnel-shaped structure to prevent reflux, the distal end of valve 13 is fixedly connected with the thick end of the funnel-shaped structure, and the proximal end of each valve 13 is closed at the thin end of the funnel-shaped structure.

[0060] It should be noted that, as shown in Figure 2 and 3 , three wire weaving units are each provided with a valve at the corresponding funnel-shaped structure, each valve remains closed when not subjected to the liquid pressure in the lumen of the stent body, and can be expanded outward to open a passage for the downward flow of liquid when subjected to the liquid pressure in the lumen of the stent body, and each valve returns to the closed state by its own elasticity when there is no liquid pressure or the pressure is very small. When the liquid in the bladder is relatively large and the pressure is relatively large, each valve is pressed from below to tightly adhere to the inclined wire of the funnel-shaped structure, the passage cannot be opened, and the function of preventing the reflux of liquid in the bladder is achieved. The fixed connection of the valve and the funnel-shaped structure of the stent body can be achieved in various ways: for example, the valve can be integrally formed with the covering layer, and the selected material can be polyurethane with a certain elasticity, the stent is woven and spliced to form a bare stent without a covering layer, then the entire bare stent is sleeved on a special-shaped lining rod, and then immersed in a polyurethane covering liquid for extraction, and after solidification, the covering layer and each valve are obtained (if necessary, the valve can be cut and trimmed); or the stent body can be covered first, and then each valve is fixed after the covering layer is formed, at this time, the lower edge of the covering layer is sutured and fixed with the upper edge of each valve, and the upper part of the valve can be fixed with the inclined wire of the funnel-shaped structure by sutures during suturing.

[0061] In one embodiment of the present application, the number of wire weaving units is three, the locking member one 9 is a double-lumen tube, the locking member two 10 is a six-lumen tube, and the hook tips of each wire anchor hook are connected in series by a traction rope 14.

[0062] It can be understood that the number of wire weaving units is preferably three, and the corresponding wire anchor hooks are also three (the six wires of the three anchor hooks are fixed by the upper six-lumen tube), and as shown in Figure 13 , the anchor hooks are placed in the bladder below the ureteral orifice to prevent the stent from moving towards the kidney, and a closed and annular traction rope is used to connect the three wire anchor hooks in series, and pulling the traction rope downward can make the wire anchor hooks converge and straighten, so that the stent is removed through the urethra from the bladder. That is, when the stent is removed, low-temperature normal saline can be injected into the ureter to make the stent wire soft and reduce the overall strength of the stent. The foreign body forceps clamps the traction rope, the three anchor hooks are straightened and tightened, and are gradually collected into the lumen of the cystoscope, and the foreign body forceps is continuously pulled to recover the entire stent.

[0063] The above merely describes preferred embodiments of the present application, and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A braided ureteral stent with anti-reflux and anti-displacement properties, characterized in that, The support body comprises a bracket body spliced ​​together in the circumferential direction from multiple metal wire braided units. The bracket body consists of a first anti-displacement section (1), a radial support section (2), an anti-backflow section (3), a bundled extension section (4), and a second anti-displacement section (5) from the distal end to the proximal end. Both the first anti-displacement section (1) and the radial support section (2) are covered with a coating layer (6). The radial support section (2) is cylindrical. The diameter of the first anti-displacement section (1) gradually increases from the proximal end to the distal end. The anti-backflow section (3) is connected to the distal end of the bundled extension section (4) through a funnel-shaped structure. An anti-backflow structure is provided at the funnel-shaped structure. The second anti-displacement section (5) consists of multiple... The bundle extension section (4) is composed of metal wire anchors evenly spaced in the circumferential direction. Each metal wire braiding unit is composed of multiple circumferential wave segments (7) and axial straight segments (8) that repeat in the axial direction on the radial support section (2). Two adjacent circumferential wave segments (7) are connected by the axial straight segments (8). Two adjacent metal wire braiding units are spliced ​​and fixed on the radial support section (2) by locking member one (9) locked on the axial straight segments (8) that are close to each other. Multiple parallel and close metal wires in the bundle extension section (4) are fixed into a bundle by locking member two (10).

2. The anti-reflux and anti-displacement braided ureteral stent according to claim 1, characterized in that, Each of the aforementioned wire braided units is made by bending and weaving a single wire.

3. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 2, characterized in that, Both ends of the same metal wire constituting the metal wire braiding unit are located at the funnel-shaped structure and are locked and fixed by locking member three (11). Two adjacent metal wire braiding units are also spliced ​​and fixed at the funnel-shaped structure by locking member three (11).

4. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 2, characterized in that, Each of the wire braided units has circumferentially adjacent circumferential wave segments (7), and two adjacent circumferential wave segments (7) are fixedly connected by a locking member (9) locked on corresponding axial straight segments (8) that are close to each other.

5. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 2, characterized in that, The metal wires of each of the metal wire braiding units are bent into an arc shape and gradually turned outward at the first anti-displacement section (1). Two adjacent metal wire braiding units are spliced ​​and fixed by a developing ring (12) located at the junction of the first anti-displacement section (1) and the radial support section (2).

6. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 2, characterized in that, The wires of each of the wire braided units are bent into a wire anchor hook in the form of double strands in the second anti-displacement section (5).

7. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 2, characterized in that, The funnel-shaped structure is formed by multiple inclined metal wires spaced apart in the circumferential direction of the support body, and the inclined metal wires gradually converge towards the central axis of the support body from the distal end to the proximal end.

8. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 7, characterized in that, Each of the inclined metal wire segments is connected to the proximal end of the radial support segment (2) via the axial straight segment (8).

9. The anti-reflux and anti-displacement braided ureteral covered stent according to claim 1, characterized in that, The anti-reflux structure is composed of multiple valves (13) arranged on the outside of the funnel-shaped structure to perform the reflux function. The distal end of the valve (13) is fixedly connected to the thick end of the funnel-shaped structure, and the proximal end of each valve (13) is closed at the thin end of the funnel-shaped structure.

10. A braided ureteral stent with anti-reflux and anti-displacement properties according to any one of claims 1 to 9, characterized in that, The number of the metal wire braiding units is three, the locking element one (9) is a double-cavity tube, the locking element two (10) is a six-cavity tube, and the hook tips of each metal wire anchor hook are connected in series by a traction rope (14).

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