Urethral stent made of degradable high polymer material

Abstract

The invention discloses a degradable high polymer material urethral stent, and belongs to the technical field of medical repair and tissue engineering, the degradable high polymer material urethral stent comprises a urethral stent body, the urethral stent body comprises an outer support ring, a net-shaped pipeline and an inner support ring, and the outer support ring and the inner support ring are integrally formed at the two ends of the net-shaped pipeline respectively; the urethral stent body is prepared from a completely degradable high polymer material, and the completely degradable high polymer material is prepared from polylactic acid, polycaprolactone, polycyclohexanone, polyglycolic acid and polylactide. Lactic acid, glycolic acid and the like can be finally degraded into non-toxic small molecules in a human body, the small molecules can be discharged through a metabolic pathway of the human body, and therefore the problem of long-term foreign matter residue is avoided; therefore, the patient does not need to suffer from pain and risk of taking out the stent through a secondary operation, and the body and economic burden of the patient is relieved.

Description

Technical Field

[0001] The invention relates to the technical field of medical repair and tissue engineering, and in particular to a urethral stent made of degradable polymer material. Background Art

[0002] Urethral stenting has been developed significantly in my country in recent years. Currently, the commonly used method in clinical practice is to place a urethral stent at the urethral stricture to expand the urethral stricture or obstruction. This stent is made of stainless steel, synthetic fiber silicone or nickel-titanium alloy, and can be placed in the urethral stricture through a cystoscope to expand the originally narrow and closed posterior urethra. Most patients with dysuria can restore urination function after the placement of a urethral stent.

[0003] The patent document with publication number CN215739691U discloses a simple anti-falling urethral stent. In view of the fact that the existing urethral stents do not have the anti-falling function, the patient's inadvertent actions will cause the position of the urethral stent to shift, and the supporting effect is poor, which will affect the treatment effect and make the treatment effect fail to reach the expected, the work efficiency is low, and the use effect is poor. The following scheme is proposed, including a urethral stent body, the outer side of the urethral stent body is provided with a plurality of transversely arranged through holes, the plurality of through holes are arranged at equal intervals, the outer side of the urethral stent body is provided with a plurality of anti-slip rings, and the inner wall of the urethral stent body is fixedly connected with a plurality of support rings.

[0004] In the above technical solution, the urethral stent is made of non-degradable materials and needs to be removed through a secondary operation, which brings additional physical and economic burdens to the patient; therefore, we propose a urethral stent made of degradable polymer materials to solve this problem. Summary of the invention

[0005] The object of the present invention is to provide a urethral stent made of a degradable polymer material to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A urethral stent made of a degradable polymer material, comprising: a urethral stent body, the urethral stent body comprising an outer support ring, a mesh pipe and an inner support ring, the outer support ring and the inner support ring are respectively integrally formed at two ends of the mesh pipe;

[0008] The urethral stent body is made of completely degradable polymer materials, and the completely degradable polymer materials are made of polylactic acid, polycaprolactone, polycyclohexanone, polyglycolic acid, and polylactide.

[0009] Preferably, when preparing the fully degradable polymer material, a PLA raw material with good biocompatibility and suitable mechanical strength is selected, and the shape and size of the urethral stent body are designed according to the anatomical structure of the urethra. The material is processed and formed by extrusion, injection molding or 3D printing. The biocompatibility of the surface of the degradable polymer material is improved by coating technology to reduce tissue reaction. The degradable polymer material is cleaned and disinfected, and the biocompatibility and mechanical properties are tested.

[0010] Preferably, the inside of the outer support ring is fixedly connected with a reinforcing ring, and the outside of the outer support ring is fixedly connected with an anti-slip ring. The appropriate catalyst and conditions are selected to synthesize PCL through ring-opening polymerization of ε-caprolactone monomer, and its surface biological activity is enhanced by plasma treatment or chemical modification. After all processing is completed, the urethral stent body is disinfected and aseptically packaged.

[0011] Preferably, when preparing the fully degradable polymer material, a polycyclohexanone raw material with good biocompatibility is selected, and according to the design parameters of the urethral stent body, a suitable molding technology such as injection molding or 3D printing is used to manufacture and shape it, and the biocompatibility of the surface of the urethral stent body is improved by specific chemical or physical methods, and disinfection and aseptic packaging are performed.

[0012] Preferably, the fully degradable polymer material is prepared by synthesizing PGA through the polymerization reaction of glycolic acid, and is made into the designed urethral stent body shape by injection molding or other suitable molding techniques. The surface of the urethral stent body is treated to enhance its performance in the body, ensure the sterility of the fully degradable polymer material, and perform strict quality control during the production process.

[0013] Preferably, when preparing the fully degradable polymer material, a polylactide material suitable for medical use is selected, the specifications of the urethral stent body are designed according to the needs of urethral support, and it is formed by methods such as injection molding, and its surface biocompatibility and stability are improved by coating or other technologies. After an appropriate post-processing process, the finished product is disinfected to ensure sterility.

[0014] Preferably, after the urethral stent body is manufactured, the surface is modified and antibacterial drugs are added to construct a superhydrophilic polycationic surface, which effectively inhibits protein adhesion and the formation of bacterial biofilms, so that the urethral stent body has antibacterial properties and further reduces the possibility of urinary tract infection.

[0015] The beneficial effects of the present invention are:

[0016] 1. In the present invention, the urethral stent made of a degradable polymer material can be finally degraded into non-toxic small molecules in the body by lactic acid, glycolic acid, etc. These small molecules can be excreted through the metabolic pathway of the human body, thereby avoiding the problem of long-term foreign body residue. Since the stent can degrade by itself after completing its function, the patient does not need to undergo the pain and risk of a second operation to remove the stent, thereby reducing the physical and economic burden on the patient;

[0017] 2. In the present invention, although the support force of the degradable polymer urethral stent may not be as good as that of the metal stent, it can have sufficient mechanical properties to keep the urethra unobstructed through material selection and structural design, thereby reducing the impact of stenosis on renal function. Good elastic recovery can prevent the stent from being completely closed when compressed, ensuring the drainage of urine;

[0018] 3. In the present invention, the urethral stent made of a degradable polymer material is specially treated, such as constructing a super-hydrophilic polycationic surface, to effectively inhibit protein adhesion and bacterial biofilm formation, thereby reducing the risk of infection. By modifying the surface of the material or adding antibacterial drugs, the degradable stent can also have antibacterial properties, thereby further reducing the possibility of urinary tract infection.

[0019] 4. In the present invention, the urethral stent made of a degradable polymer material can reduce the risk of complications such as stone formation, bacterial infection, inflammation and restenosis compared with the traditional non-degradable stent. Since secondary surgery is avoided and complications are reduced, the overall quality of life of the patient is significantly improved;

[0020] 5. In the present invention, the urethral stent made of a degradable polymer material can accurately control the degradation time of the stent according to clinical needs by adjusting the molecular weight, crystallinity, copolymer ratio, etc. of the material to match the ureteral recovery cycle. Although the visibility of the degradable stent under X-ray is poor, researchers are working hard to improve its imaging ability so that it can be accurately tracked after implantation;

[0021] 6. In the present invention, the urethral stent made of a degradable polymer material avoids secondary surgery, reduces the additional treatment costs caused by complications, and thus alleviates the overall medical burden. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the three-dimensional structure of a urethral stent made of a degradable polymer material proposed in the present invention.

[0023] In the figure: 1. urethral stent body; 101. mesh tube; 102. outer support ring; 1021. reinforcement ring; 1022. anti-slip ring; 103. inner support ring. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0025] Reference Figure 1 A urethral stent made of a degradable polymer material comprises: a urethral stent body 1, the urethral stent body 1 comprises an outer support ring 102, a mesh pipe 101 and an inner support ring 103, the outer support ring 102 and the inner support ring 103 are integrally formed at both ends of the mesh pipe 101;

[0026] The urethral stent body 1 is made of completely degradable polymer materials, and the completely degradable polymer materials are made of polylactic acid, polycaprolactone, polycyclohexanone, polyglycolic acid, and polylactide.

[0027] In this embodiment, PLA raw materials with good biocompatibility and suitable mechanical strength are selected when preparing fully degradable polymer materials, and the shape and size of the urethral stent body 1 are designed according to the anatomical structure of the urethra. The material is processed and formed by extrusion, injection molding or 3D printing. The biocompatibility of the surface of the degradable polymer material is improved by coating technology to reduce tissue reaction. The degradable polymer material is cleaned and disinfected, and the biocompatibility and mechanical properties are tested.

[0028] In this embodiment, the inner part of the outer support ring 102 is fixedly connected with a reinforcing ring 1021, and the outer side of the outer support ring 102 is fixedly connected with an anti-slip ring 1022. Suitable catalysts and conditions are selected to synthesize PCL through ring-opening polymerization of ε-caprolactone monomer, and its surface biological activity is enhanced by plasma treatment or chemical modification. After all processing is completed, the urethral stent body 1 is disinfected and aseptically packaged.

[0029] In this embodiment, a polycyclohexanone raw material with good biocompatibility is selected when preparing the fully degradable polymer material. According to the design parameters of the urethral stent body 1, a suitable molding technology such as injection molding or 3D printing is used to manufacture and shape it. The biocompatibility of the surface of the urethral stent body 1 is improved by specific chemical or physical methods, and disinfection and aseptic packaging are performed.

[0030] In this embodiment, the fully degradable polymer material is prepared by synthesizing PGA through the polymerization reaction of glycolic acid, and is made into the designed shape of the urethral stent body 1 by injection molding or other suitable molding techniques. The surface of the urethral stent body 1 is treated to enhance its performance in the body, ensure the sterility of the fully degradable polymer material, and perform strict quality control during the production process.

[0031] In this embodiment, a polylactide material suitable for medical use is selected when preparing the fully degradable polymer material, the specifications of the urethral stent body 1 are designed according to the needs of urethral support, and it is formed by injection molding and other methods, and its surface biocompatibility and stability are improved by coating or other technologies. After appropriate post-processing processes, the finished product is disinfected to ensure sterility.

[0032] In this embodiment, after the urethral stent body 1 is manufactured, the surface is modified and antibacterial drugs are added to construct a superhydrophilic polycationic surface, which effectively inhibits protein adhesion and the formation of bacterial biofilms, so that the urethral stent body 1 has antibacterial properties and further reduces the possibility of urinary tract infection.

[0033] In this embodiment, lactic acid, glycolic acid, etc. can be finally degraded into non-toxic small molecules in the body, and these small molecules can be excreted through the body's metabolic pathways, thereby avoiding the problem of long-term foreign body residues. Since the stent can degrade by itself after completing its function, the patient does not need to undergo the pain and risk of a second operation to remove the stent, thereby reducing the patient's physical and economic burden. Although the supporting force of the degradable stent may not be as good as that of a metal stent, through material selection and structural design, it can have sufficient mechanical properties to keep the urethra unobstructed, thereby reducing the impact of stenosis on renal function. Good elastic recovery can prevent the stent from being completely closed when compressed, thereby ensuring the drainage of urine. By special treatment of the urethral stent, such as constructing a super-hydrophilic polycationic surface, protein adhesion and the formation of bacterial biofilms can be effectively inhibited, reducing sensitivity. In order to reduce the risk of infection, the biodegradable stent can also have antibacterial properties through material surface modification or adding antibacterial drugs, further reducing the possibility of urinary tract infection. Compared with traditional non-degradable stents, biodegradable stents can reduce the risks of complications such as stone formation, bacterial infection, inflammation and restenosis. Since secondary surgery is avoided and complications are reduced, the overall quality of life of patients is significantly improved. By adjusting the molecular weight, crystallinity, copolymer ratio, etc. of the material, the degradation time of the stent can be precisely controlled according to clinical needs to match it with the ureteral recovery cycle. Although the visibility of the biodegradable stent under X-ray is poor, researchers are working hard to improve its imaging ability so that it can be accurately tracked after implantation. Since secondary surgery is avoided, the additional treatment costs caused by complications are reduced, thereby reducing the overall medical burden.

[0034] The above is a detailed introduction to a urethral stent made of a degradable polymer material provided by the present invention. Specific embodiments are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A urethral stent made of degradable polymer material, characterized in that: include: A urethral stent body (1), the urethral stent body (1) comprising an outer support ring (102), a mesh pipe (101) and an inner support ring (103), the outer support ring (102) and the inner support ring (103) being integrally formed at two ends of the mesh pipe (101); The urethral stent body (1) is made of completely degradable polymer materials, and the completely degradable polymer materials are made of polylactic acid, polycaprolactone, polycyclohexanone, polyglycolic acid, and polylactide.

2. The urethral stent made of degradable polymer material according to claim 1, characterized in that: When preparing the fully degradable polymer material, a PLA raw material with good biocompatibility and suitable mechanical strength is selected, and the shape and size of the urethral stent body (1) are designed according to the anatomical structure of the urethra. The material is processed and formed by extrusion, injection molding or 3D printing. The biocompatibility of the surface of the degradable polymer material is improved by coating technology to reduce tissue reaction. The degradable polymer material is cleaned and disinfected, and biocompatibility and mechanical property tests are performed.

3. The urethral stent made of degradable polymer material according to claim 1, characterized in that: The inner part of the outer support ring (102) is fixedly connected with a reinforcing ring (1021), and the outer side of the outer support ring (102) is fixedly connected with an anti-slip ring (1022). The PCL is synthesized by ring-opening polymerization of ε-caprolactone monomer by selecting suitable catalysts and conditions, and its surface biological activity is enhanced by plasma treatment or chemical modification. After all processing is completed, the urethral stent body (1) is disinfected and aseptically packaged.

4. The urethral stent made of degradable polymer material according to claim 1, characterized in that: When preparing the fully degradable polymer material, a polycyclohexanone raw material with good biocompatibility is selected. According to the design parameters of the urethral stent body (1), a suitable molding technology such as injection molding or 3D printing is used to manufacture and mold the material. The biocompatibility of the surface of the urethral stent body (1) is improved by a specific chemical or physical method, and the material is disinfected and aseptically packaged.

5. The urethral stent made of degradable polymer material according to claim 1, characterized in that: The fully degradable polymer material is prepared by synthesizing PGA through the polymerization reaction of glycolic acid, and is made into the designed shape of the urethral stent body (1) by injection molding or other suitable molding techniques. The surface of the urethral stent body (1) is treated to enhance its performance in the body, ensure the sterility of the fully degradable polymer material, and perform strict quality control during the production process.

6. The urethral stent made of degradable polymer material according to claim 1, characterized in that: When preparing the fully degradable polymer material, a polylactide material suitable for medical use is selected, the specifications of the urethral stent body (1) are designed according to the requirements of urethral support, and it is formed by injection molding or other methods, and its surface biocompatibility and stability are improved by coating or other technologies. After appropriate post-processing processes, the finished product is disinfected to ensure sterility.

7. The urethral stent made of degradable polymer material according to claim 1, characterized in that: After the urethral stent body (1) is manufactured, the surface is modified and antibacterial drugs are added to construct a super-hydrophilic polycationic surface, which effectively inhibits protein adhesion and the formation of bacterial biofilms, so that the urethral stent body (1) has antibacterial properties, further reducing the possibility of urinary tract infection.

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