CN112107782A

CN112107782A - Ureteral stent

Info

Publication number: CN112107782A
Application number: CN202011074034.7A
Authority: CN
Inventors: 李星智; 冯耿超; 赵昱
Original assignee: Shenzhen Surgscience Medical Technology Co ltd
Current assignee: Shenzhen Surgscience Medical Technology Co ltd
Priority date: 2020-10-09
Filing date: 2020-10-09
Publication date: 2020-12-22

Abstract

The invention discloses a ureteral stent tube, which comprises a hollow tubular self-expansion part and hollow holding parts arranged at two ends or one end of the self-expansion part, wherein the self-expansion part and the holding parts at two ends or one end of the self-expansion part are combined into an integral structure and are communicated with each other, the self-expansion part comprises a working part and transition parts integrally formed with two ends or one end of the working part, one end of the transition part is communicated with the working part, and the other end of the transition part is communicated with the holding part. The self-expandable portion includes a support frame and a thin film covering the support frame. The holding portion is used for hanging and holding in the kidney and/or bladder. The ureteral stent tube provided by the invention can be more firmly fixed in a ureter, the working part of the ureteral stent tube is more attached and stable with the ureter, and the ureteral stent tube can not cause the stent to move upwards and/or downwards due to the movement of a patient.

Description

Ureteral stent

Technical Field

The invention relates to the technical field of medical instruments, in particular to a ureteral stent tube which can be placed into a human body.

Background

The ureter is a tubular passage in the body that transports urine from the kidney to the bladder. Ureteral stent tubes are used in a very wide range of urological and gynecological procedures, for facilitating drainage of urine from the kidney to the bladder, overcoming narrowing of the ureter and blockage of the duct by lesions, during or after surgery in patients with ureteral obstruction or injury, or for protecting the integrity of the ureter in various surgical procedures.

At present, the ureteral stent on the market is mainly a double J tube, that is, one end or two ends of the ureteral stent can be coiled into a ring-shaped pigtail shape and is used for being fixed on a renal pelvis and a bladder respectively to prevent the stent from migrating upwards and/or downwards due to the movement of a patient and perform internal drainage from the kidney to the bladder, however, clinically, pathological stenosis of the ureter sometimes causes the ureteral stent tube to be difficult to place or the stent is not matched with the ureter to cause stent displacement or deformation, the double J tube ureteral stent tube cannot expand the stenosis of the ureter after being placed, and cannot be well fitted with the ureter or even cannot fix the ureteral stent tube on the ureter.

Disclosure of Invention

The invention aims to solve the problems of ureter stenosis, difficulty in taking out a ureter stent tube and the like in the prior art and simultaneously also solves the problems that the ureter stent tube is easy to slide and the like. The invention provides a ureteral stent, which comprises a hollow tubular self-expansion part and hollow holding parts arranged at two ends or one end of the self-expansion part, wherein the self-expansion part and the holding parts at two ends or one end of the self-expansion part are combined into an integral structure and are communicated with each other, the self-expansion part comprises a working part and transition parts integrally formed with two ends or one end of the working part, the holding parts comprise straight cylinder parts and curled parts, one end of each transition part is communicated with the working part, and the other end of each transition part is communicated with the straight cylinder parts.

Optionally, the transition part is a hollow conical part, and a sleeving overlapping part exists between the transition part and the straight barrel part and is welded together by ultrasonic wave, electromagnetic wave, laser or infrared, or is welded together by heating, or is firmly connected together by an adhesive.

Optionally, when the ureteral stent tube comprises a self-expansion part in a hollow round tube shape and hollow holding parts arranged at two ends of the self-expansion part, the position of the self-expansion part is close to any curled part of the ureteral stent tube or is positioned in the middle of the ureteral stent tube.

Optionally, the length of the self-expanding portion is 1/8-1/2 of the total length of the ureteral stent tube.

Optionally, the length of the self-expanding portion is 1/3-1/2 of the total length of the ureteral stent tube.

Optionally, the ratio of the diameter of the working portion to the diameter of the holding portion is in the range of 1.5:1 to 15: 1.

Optionally, the ratio of the diameter of the working portion to the diameter of the holding portion is 8: 1.

Optionally, the self-expandable portion includes a support skeleton and a thin film covering the support skeleton.

Optionally, the supporting skeleton is in a net structure or a sine or cosine wave structure which rises or falls in a spiral manner.

Optionally, the supporting framework of the self-expanding portion is a sine or cosine wave-shaped structure processed by the same framework.

Optionally, the material of the supporting framework is metal or alloy.

Optionally, the material of the support skeleton is a shape memory alloy.

Optionally, the material of the support skeleton is a two-way shape memory alloy.

Optionally, both ends of the working portion are provided with developing portions.

Optionally, the film is of a single-layer structure and covers the inner side or the outer side of the support skeleton.

Optionally, the film is of a double-layer structure and includes an inner layer film and an outer layer film, and the inner layer film and the outer layer film respectively cover the inner side and the outer side of the support framework.

Optionally, the curl is in the shape of one or more loops of a pigtail, the curl being for retention in the kidney and/or bladder.

Optionally, the tube wall of the curled part has a plurality of through holes.

Optionally, the exterior surface of the ureteral stent tube is coated with a hydrophilic coating.

Optionally, the self-expanding portion has a break-away portion.

The invention also provides a kit comprising a ureteral stent tube as described in any of the above.

The invention has the beneficial effects that:

(1) compared with the prior art, the ureteral stent tube can be more firmly fixed in a ureter, and the working part of the ureteral stent tube is more attached to and firmer with the ureter.

(2) The shape of the retention portion of the ureteral stent tube is such that the ureteral stent tube does not migrate the stent up and/or down due to patient movement, thereby generally enhancing the stability of the ureteral stent tube in the renal pelvis, ureter, and bladder of the human body.

(3) At low temperature, the ureteral stent contracts and is easy to take out from the body, and the damage to tissues and organs of the body is small.

The above discussion is intended to be merely illustrative of each and every aspect of the present related art in the technical field of the present invention, and should not be construed as negating the scope of the claims.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a schematic view of an exemplary embodiment of a ureteral stent of the present application;

FIG. 2 is a schematic view of another exemplary embodiment of a ureteral stent of the present application;

FIG. 3 is a schematic view of yet another exemplary embodiment of a ureteral stent of the present application;

FIG. 4 is a schematic view of yet another exemplary embodiment of a ureteral stent of the present application;

FIG. 5 is a schematic view of the ureteral stent tube of FIG. 1 with a break away;

FIG. 6 is a schematic view of the ureteral stent tube of FIG. 2 with a break away;

FIG. 7 is a schematic view of the ureteral stent tube of FIG. 3 with a break away;

fig. 8 is a schematic view of the ureteral stent tube of fig. 4 with a break away.

Detailed Description

The following description of certain embodiments of the invention is not limited in its application to the details of construction and the arrangement of components set forth in the accompanying drawings and description. The illustrated embodiments of the invention are capable of being practiced or being incorporated in other embodiments, variations and modifications, and may be practiced or carried out in various ways. Furthermore, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative embodiments of the present invention for the convenience of the reader and are not for the purpose of limiting the invention.

It should be understood that the term "end" as used herein should be understood to refer to a longitudinal boundary, or a surface representing such a boundary. "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In addition, it is to be understood that any one or more of the following-described embodiments, expressions of embodiments, examples, etc. can be combined with any one or more of the other following-described embodiments, expressions of embodiments, examples, etc.

Fig. 1 is a schematic structural diagram of an embodiment of a ureteral stent provided in the present application. Referring to fig. 1, a ureteral stent 100 according to the present invention includes a self-expanding portion 110 having a hollow circular tube shape and hollow holding portions 120 provided at both ends of the self-expanding portion 110, and the self-expanding portion 110 and the holding portions 120 at both ends thereof are integrated into an integral structure and communicate with each other. The self-expanding part 110 is made of a material capable of radially expanding and supporting a narrow ureter, so that the ureter is free from obstruction and the ureter is kept smooth. The self-expanding portion 110 and the holding portion 120 are combined to form an integral body through a certain process. Since the ureteral stent is used for treating diseases in ureter to assist the urine of human body to smoothly flow into the bladder from renal pelvis, the whole ureteral stent is communicated, and the urine can smoothly pass through the ureteral stent. The self-expanding portion 110 includes a working portion 111 and transition portions 112 integrally formed with both ends of the working portion. One end of the transition portion 112 communicates with the working portion 111 and the other end thereof communicates with the holding portion 120. The holding portion includes a straight tube portion 121 and a curled portion 122 integrally molded from the same material. The two crimps at both ends of the ureteral stent tube may be the same or different shapes and may be located on different sides or the same side of the working portion 111. One of the two crimps 122 is placed into the renal pelvis and suspended therein, and the other is placed into the bladder and retained therein. The length of the straight cylinder portions on both sides of the self-expanding portion 110 may be selected according to actual needs, for example, the length of the straight cylinder portion on one side is longer, and the length of the straight cylinder portion on the other side is shorter; or the lengths of the straight cylinder parts on both sides are the same. The length of the straight tube part on both sides of the self-expansion part 110 is determined according to the specific part of the ureteral stenosis or lesion, and the length of the working part is just enough to cover the part of the stenosis or lesion.

Fig. 2 is a schematic structural diagram of another embodiment of a ureteral stent provided in the present application. Referring to fig. 2, the ureteral stent 200 according to the present invention includes a self-expanding portion 210 having a hollow circular tube shape and a hollow holding portion 220 disposed at one end of the self-expanding portion 210, the self-expanding portion 210 and the holding portion 220 at one end thereof are integrated into a single structure and communicate with each other, and the self-expanding portion 210 includes a working portion 211 and a transition portion 212 integrally formed with one end of the working portion. The holding portion 220 includes a straight tube portion 221 and a curl portion 222 integrally formed of the same material. One end of the transition portion 212 communicates with the working portion 211 and the other end thereof communicates with the straight portion 221. This curl 222 can be placed into and retained within the renal pelvis. The length of the straight barrel portion 221 can be selected according to the needs of the physician. The length of the straight tube portion 221 is selected primarily based on the fact that the length of the working portion of the ureteral stent is just sufficient to function at the specific location of the ureteral stenosis or lesion.

Preferably, the transition portions 112,212 each comprise a hollow conical portion. More preferably, the transition portion 112,212 includes, in addition to the hollow conical portion, a connecting portion extending from a distal end of the hollow conical portion in communication with the straight portion. The diameter of the connecting part is slightly larger or smaller than that of the straight cylinder part. The hollow conical part and the connecting part are integrally formed by the same material.

The connecting portion may have the holding portion 120,220 formed thereon by over-molding so that the connecting portion and the holding portion 120,220 are integrated. Also, a bell-spigot overlapping portion may exist between the joining portion and the

straight portions

121 and 221 and the bell-spigot overlapping portions are welded together by ultrasonic, electromagnetic, laser, or infrared welding, or are welded together by heating, or are firmly joined together by an adhesive.

In one embodiment, the muff-coupling overlapping portions between the coupling portion and the straight tube portion 121,221 are coupled together by a method comprising the steps of: (1) placing the connecting part into the straight cylinder part or placing the straight cylinder part into the connecting part so as to form a sleeving and overlapping part; (2) the sleeve overlapping portions of the straight tube portion and the holding portion are welded together by ultrasonic waves, electromagnetic waves, laser light, or infrared rays, or are welded by heating, or are firmly connected by an adhesive, so that the connecting portion and the straight tube portion are firmly connected together into a single body.

The ureter may be sequentially divided into an upper segment, a middle segment, and a lower segment in the order from the renal pelvis to the bladder, and the stricture portion of the ureter may be located at any one or several positions of the upper segment, the middle segment, and the lower segment. In one embodiment, the self-expandable portion is positioned near any of the retention portions of the ureteral stent tube, when the stricture portion of the corresponding ureter is near the renal pelvis or bladder, i.e., at an upper or lower segment of the entire ureteral stent tube, e.g., fig. 3-4 or fig. 7-8. In addition, the location of the self-expanding section may also be located in the middle of the ureteral stent tube, where the corresponding stricture of the ureter is located in the middle of the ureter, e.g. fig. 1 or 5. When the ureteral stricture portion may be located at a plurality of positions, a plurality of self-expandable portions may be provided, or the length of the self-expandable portion may be increased.

The length of the self-expanding portion (more specifically, the length of the working portion) is selected according to the length of the ureteral stricture site. In one embodiment, when the ureteral stent tube comprises a self-expansion part in a hollow round tube shape and holding parts arranged at two ends of the self-expansion part, the length of the self-expansion part accounts for 1/8-1/2 of the whole length of the ureteral stent tube. In one embodiment, the length of the self-expanding portion is 1/3-1/2 of the overall length of the ureteral stent tube.

In one embodiment, both ends of the working portion are provided with the developing portions. The visualization portion is a radiopaque visualization portion. The developing part is a fixed anchor point, i.e., an anchor point, for displaying a fixed position under fluoroscopy or X-ray and thus confirming whether the stent tube is correctly placed, i.e., the stent tube is placed at a lesion position or a position requiring expansion. The material of the anchor points is a metal developed under X-rays, for example, tantalum, platinum.

The self-expanding portion 110,210 and the holding portion 120,220 are both hollow structures so that they allow urine to smoothly circulate. The diameter ratio of the working portion 111,211 to the holding portion 120,220 is: 1.5:1 to 15:1, e.g., 2:1, 3:1, 5:1, 8:1, 10:1, or 15: 1. Preferably, the ratio of the diameter of the working portion to the diameter of the holding portion is 8: 1. Depending on the diameter size of the ureter, the working portion 111,211 may have an inner diameter of 5-15mm, e.g., 5mm, 8mm, 10mm, 12mm, 13mm, or 15 mm; depending on the length of the ureter, the adult ureter may have an overall length of 25 to 35 cm, and the working portion may have a working length of 5 to 25cm, for example, 5cm, 10cm, 15cm, 18cm, 20cm, 23cm, 24cm, or 25 cm. The working portion and the retaining portion have a difference in diameter and are therefore connected and transitioned through the transition portion 112, 212. The end of the transition portion 112,212 that is contiguous with the working portion 111,211 (i.e., the end of the hollow conical portion) has the same diameter as the working

portion

111, 211. The other end of the transition portion 112,212, which is connected to the holding portion 120,210, is the smallest in diameter. The retaining portion 120,220 has a constant diameter or tapers in diameter from its connection with the transition portion. Preferably, the retaining portion has a fixed diameter. The retaining portion has an inner diameter in the range of 0.5-1.3mm, e.g., 0.5mm, 0.8mm, 1.0mm, or 1.3 mm. There is a difference in diameter between the working portion 111,211 and the holding portion 120,220, the working portion 111,211 being held in the ureter and abutting against the wall of the ureter, and acting to expand a lesion (or stricture) in the ureter, the straight tube portion remaining in the ureter, and the coil portion being held in the renal pelvis and/or bladder.

The ureteral stent tube 100,200 according to the embodiment of the present invention is used in an operation, the ureteral stent tube 100,200 is inserted into the natural passage urethra of the human body, one end of the ureteral stent tube 100,200 is passed through the bladder and the ureter to reach the renal pelvis and is retained in the renal pelvis, and the other end is naturally suspended in the bladder and is retained therein (if any). The working portion 111,211 is held in the narrow part of the ureter. After the ureteral stent tube 100 is placed into the ureter, one of the two curled parts 122 is clamped into the bladder and the other is clamped into the renal pelvis, so that the whole ureteral stent tube 100 is not easy to move up and down, and the effects of supporting the ureter and draining urine are achieved. After the ureteral stent tube 200 is placed into the ureter, the curled portion 222 is snapped into the renal pelvis, so that the entire ureteral stent tube is not easy to slip out of the renal pelvis. Urine produced in the renal pelvis of the human body is guided into the bladder of the human body through the ureteral stent tube and is discharged through the bladder.

In one embodiment, the self-expanding portion 111,211 comprises a support armature 114,214 and a membrane 115 overlying the support armature. Preferably, the supporting framework 114,214 is a net structure forming a tubular hollow structure, or a sine or cosine wave structure spirally rising or falling, and has the function of supporting the ureter and can be attached to the wall of the ureter when self-expanding. The net structure of the ureteral stent wall or the sine or cosine wave structure which ascends or descends in a spiral mode has high bending resistance, so that the

support frameworks

114 and 214 still keep soft after being repeatedly bent, and meanwhile, folds cannot be generated to influence the flow guide of urine. The contact area between the working part and the ureter can be effectively increased, and the friction force between the bracket and the inner wall of the ureter is increased, so that the ureter bracket is not easy to slip and move in the ureter. Since the supporting skeleton has a sine or cosine waveform, the thin film is embedded in the metal stent after the metal stent is expanded or contracted to be deformed.

The support frame is divided into metals or alloys, such as stainless steel, titanium or titanium alloys, etc., from the material from which the stent is made. Stainless steel stents have good elasticity and tension, but stainless steel is very easily eroded in chloride ions of body fluids, and when the eroded chloride ions enter surrounding tissues, adverse reactions including inflammatory pain, discoloration, fibrosis and the like are generated.

The ureteral stent of the invention proposes to use shape memory alloy to make the supporting

framework

114, 214. More preferably, the ureteral stent tubes of the present invention employ support backbones 114,214 made of a two-way shape memory alloy, preferably a nickel titanium two-way shape memory alloy. The titanium or titanium alloy stent has shape memory effect, superelasticity, high corrosion resistance, good biocompatibility and tissue tolerance, and is ideal as a permanent in vivo stent. When the supporting frame 114,214 has two-way shape memory, it has double memory points. When the bracket is delivered, ice water or low-temperature normal saline is required to be injected to keep the temperature of the bracket below the body temperature, after the ureteral bracket tube is applied to a preset position in a human body, the injection of the ice water or the low-temperature saline is stopped, the body temperature of the human body causes the self-expansion fixation to be generated in the process that the supporting framework of the self-expansion part 110,210 of the ureteral bracket tube is raised from the room temperature to the temperature of the human body, and therefore the working part of the ureteral bracket tube 100,200 is jointed with the wall of the ureter. When the ureteral stent 100,200 is taken out, circulating ice water or low-temperature normal saline is introduced into the saccule to reduce the temperature in the urinary tract lumen, so that the support framework is contracted to the second memory state, namely, the support framework is restored to the low-temperature shape, and the ureteral stent 100,200 is convenient to take out from the ureter. The support frame 114,214 is in a contracted memory configuration at 5-15 degrees Celsius (i.e., the temperature of the low temperature saline solution) and an expanded memory configuration at 36 degrees Celsius (i.e., the temperature after warming, the temperature of the human body).

The frozen memory makes the operation convenient. The ureteral stent can automatically recover and expand in a body temperature state, has a shape memory function, is tightly jointed with a urethral wall, and is not easy to slide out or shift, and meanwhile, the titanium-nickel alloy has good biocompatibility, tissue tolerance and high corrosion resistance, so that the reliability is good.

The alloy with memory effect includes Au-Cd, Ag-Cd, Cu-Zn, Ti-Ni-Pd, Ti-Nb, etc. the present invention preferably uses TiNi alloy with good memory effect. The material of the two-way shape memory alloy spring is TiNi alloy.

The support frame 114,214 is preferably a unitary structure to ensure the integrity of the support frame 114,214 and the strength of the connection throughout. Preferably, the supporting framework of the working portion 111,211 and the transition portion 112,212 is made of the same framework. The support frame 114,214 may be fabricated in a woven manner, a laser engraving method, or a 3D printing method. In this embodiment, a 3D printing method is preferably used to improve the production efficiency of the supporting

frames

114, 214. The 3D printing method is a rapid forming method, and is a technology for constructing an object by using a bondable material such as powdered metal or plastic and the like in a layer-by-layer printing mode on the basis of a digital model file, so that the manufacturing efficiency is high, and the limitation on the manufacturing shape and the used material of a product is small.

A film covered on the supporting framework 114,214, wherein the material is any one or any combination of the following groups: PTFE, ePTFE, polyurethane, SEBS, silicone-modified polyurethane, EVA, silicone-modified polyurethane, TPE, polyester fiber, silicone gel, or thermoplastic elastomer, and the like. The film may be a single layer structure covering the inside or outside of the

support frame

114, 214. A film is preferably applied over the outside of the support frame 114,214 to improve the seal of the film against the ureteral lesion. The film may also be a bilayer structure, i.e., comprising an outer film and an inner film, which cover the outer and inner sides of the supporting armatures 114,214, respectively. The outer layer film and the inner layer film can be supported by the same material in the materials or made of different materials. In order to avoid the problem that films made of the same material are easy to be simultaneously problematic, when the films have a double-layer structure, the films are preferably made of different materials. For example, the inner layer film can be made of smooth hydrophobic materials, and has good hydrophobic performance and good drainage effect. The inner film mainly has the function of providing a smooth inner surface for the ureteral stent, so that fluid (such as urine) can smoothly pass through the inner surface, the smoothness of the inner cavity of the ureteral stent is improved, the surface of the inner film is smooth, and the fluid can conveniently pass through the inner surface. The inner film may be made of various materials that can be used for human body, for example, in some embodiments of the present invention, the inner film is made of vinyl, or fluorine-containing materials. Preferably, the portions of the outer and inner films that are positioned in the hollow-outs of the support frame 114,214 are bonded together, such as by adhesive bonding, to improve the integrity of the entire working

portion

111, 211.

The holding part 120,220 is a hollow circular tube and is non-expanded, and its curled part is bent inward or outward in a circle shape such as a pigtail shape for holding in the kidney and/or bladder without falling off. In one embodiment, the curl 122,222 forms a pigtail-like structure (i.e., loop-like) in the operative state. The purpose of the crimp 122,222 is to prevent the ureteral stent tube from migrating up and/or down due to patient movement. Preferably, the pigtail of the coil may have a shape having a loop structure of one or more loops. The outer diameter of the annular structure is 10-30 mm. The holding portion 120,220 is formed by a material having a good elasticity, and may be any one or any combination selected from the following group: silica gel, natural rubber, polyurethane, silicone-modified polyurethane, EVA, silicone-modified polyurethane, TPE, polyvinyl chloride (PVC), and the like. These materials are soft and durable and have high bending resistance. For example, in some embodiments of the present invention, the retaining portions 120,220 are made of a polyurethane material, which has good memory properties.

In one embodiment, the retention portion 120,220 has a plurality of through holes 123,223 in the wall thereof to guide more urine in the ureteral stent 100 to exit through the ureteral stent, and these through holes are mainly located in the curled portion. The specific number of the through holes 123,223 is not particularly limited, and may be set according to actual needs. In some embodiments of the invention, the holding portions at both ends or one end of the ureteral stent tube are each provided with 3 to 15 through holes. The shape of the through hole is preferably a circular hole. The diameter of the through hole is 1-1.2 mm. Furthermore, in this embodiment, the ureteral stent tube has a greater drainage effect.

In one embodiment, the exterior surface of the ureteral stent tube may be coated with a hydrophilic coating. The hydrophilic coating material comprises, for example, a hydrophilic polymer polyvinylpyrrolidone 15, can be easily combined with water to form a hydrophilic gel, has excellent biocompatibility, and has a super-lubricating effect in clinical use, so that the smoothness of the surface of the ureteral stent tube is improved, the smoothness of the catheter placement is further facilitated, and the urinary calculus probability of the external surface of the ureteral stent tube is reduced.

In one embodiment, the self-expanding portion has a break-away portion. The self-expanding portion of the ureteral stent tube as shown in fig. 5-8 has a break-away

portion

115, 215. The part of disassembling, nick or recess promptly, can be disassembled into a rectangular along this ureteral stent's of this part of disassembling working part and transition portion, smoothly and take out the ureteral stent who disassembles in following the human body fast, cause as little injury as possible to the human body.

In one embodiment, the self-expanding portion may or may not have a break-away portion. The ureteral stent tube shown in fig. 1-4 does not have a disassembled portion.

In another aspect of the embodiments of the present invention, there is provided a kit including: the

ureteral stent tubes

100 and 200 of any one of the above items further comprise a booster tube, a guide wire and the like. The boosting tube is a hollow long tube, both ends of the boosting tube are open, and the tube wall of the boosting tube is formed by wrapping a spring ring made of nickel-titanium alloy in polytetrafluoroethylene. The booster tube has a length in the range of 8 to 60cm, for example, 40cm, 45cm, 50cm, etc. The outside diameter of the booster tube wall is in the range of 4F-10F, such as 4F, 5F, 7F, 8F, 10F. The boosting tube has the advantages of super-strong compression resistance, large thrust and 5-turn/mm spring ring density. The boosting tube is used for pushing the ureteral stent tube to promote the ureteral stent tube to enter a human body. The present kit has the same structure and benefits as the ureteral stent tube 100 in the previous embodiment. The kit may also include a pusher, a guidewire, a retaining clip, and the like. Since the structure and advantageous effects of the ureteral stent 100,200 have been described in detail in the foregoing embodiments, no further description is given here.

In the description herein, references to the terms "one embodiment," "an embodiment," "as shown in FIG. …," "for example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.

Although embodiments of the present invention have been shown and described, it is understood that the embodiments are illustrative and not restrictive, and that all equivalent modifications or changes that may be made by those skilled in the art without departing from the spirit and scope of the present invention as disclosed herein are intended to be covered by the appended claims.

Claims

1. A ureteral stent is characterized by comprising a hollow tubular self-expansion part and hollow holding parts arranged at two ends or one end of the self-expansion part, wherein the self-expansion part and the holding parts at two ends or one end of the self-expansion part are combined into an integral structure and are communicated with each other, the self-expansion part comprises a working part and transition parts integrally formed with two ends or one end of the working part, the holding parts comprise a straight cylinder part and a curled part which are integrally formed by the same material, one end of the transition part is communicated with the working part, and the other end of the transition part is communicated with the straight cylinder part.

2. The ureteral stent tube according to claim 1, wherein the transition portion is a hollow conical portion, a sleeving overlap portion exists between the transition portion and the straight tube portion, and the sleeving overlap portion is welded together by ultrasonic, electromagnetic, laser or infrared welding, or welded together by heating, or firmly connected together by an adhesive.

3. The ureteral stent tube according to claim 2, wherein, when the ureteral stent tube includes a self-expanding portion in a hollow round tube shape and hollow holding portions provided at both ends of the self-expanding portion, the self-expanding portion is located near any one of the crimping portions of the ureteral stent tube or at a middle portion of the ureteral stent tube.

4. The ureteral stent tube according to claim 3, wherein the length of the self-expanding portion is 1/8-1/2 of the overall length of the ureteral stent tube.

5. The ureteral stent of claim 4, wherein the length of the self-expanding section is 1/3-1/2 of the overall length of the ureteral stent tube.

6. The ureteral stent tube according to claim 2, wherein a ratio of the diameter of the working portion to the diameter of the retention portion ranges from 1.5:1 to 15: 1.

7. The ureteral stent tube according to claim 6, wherein a ratio of the diameter of the working portion to the diameter of the retention portion is 8: 1.

8. The ureteral stent tube according to claim 2, wherein the self-expanding portion includes a support skeleton and a film covering the support skeleton.

9. The ureteral stent tube according to claim 8, wherein the support scaffold is in a mesh structure, or in a sine or cosine wave structure that rises or falls helically.

10. The ureteral stent tube according to claim 9, wherein the support skeleton of the self-expanding portion is a sine or cosine wave-shaped structure processed from the same skeleton.

11. The ureteral stent tube according to claim 10, wherein the material of the support scaffold is a metal or an alloy.

12. The ureteral stent tube of claim 11, wherein the material of the support scaffold is a shape memory alloy.

13. The ureteral stent tube according to claim 12, wherein the material of the support scaffold is a two-way shape memory alloy.

14. The ureteral stent tube according to claim 8, wherein both ends of the working portion are provided with visualization portions.

15. The ureteral stent tube according to claim 8, wherein the film is a single layer structure and covers the inside or outside of the support scaffold.

16. The ureteral stent tube according to claim 8, wherein the thin film has a double-layer structure and includes an inner film and an outer film, the inner film and the outer film respectively covering the inner side and the outer side of the support frame.

17. The ureteral stent tube according to any of claim 2, wherein the shape of the coil is one or more turns of a pigtail shape, the coil being for retention in the kidney and/or bladder.

18. The ureteral stent tube according to claim 17, wherein the wall of the crimp portion has a plurality of through holes therein.

19. The ureteral stent tube according to claim 2, wherein an outer surface of the ureteral stent tube is coated with a hydrophilic coating.

20. The ureteral stent tube of any of claims 1 to 19, wherein the self-expanding portion has a break-away portion.

21. A kit comprising the ureteral stent tube of any of claims 1 to 20.