Anti-reflux ureteral stent
By setting a hollow expansion section and an internal valve structure in the bladder segment of the ureteral stent, the problem of urine reflux in the ureteral stent was solved, achieving antegrade drainage and reliable anti-reflux effect, ensuring the convenience and safety of the surgical procedure.
Patent Information
- Application Number
- CN202521198263.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-12
- Publication Date
- 2026-05-15
- Estimated Expiration
- 2035-06-12
AI Technical Summary
Existing ureteral stents are prone to causing reflux of urine into the bladder after placement, leading to increased intrarenal pressure and complications, and there is a lack of effective anti-reflux solutions.
A reflux-resistant ureteral stent is designed by setting a hollow expansion section in the bladder segment of the stent and embedding a multi-leaflet one-way valve. The automatic opening and closing of the valve enables one-way drainage and prevents urine from flowing back.
This method achieves antegrade drainage from the kidney to the bladder while reliably sealing the lumen to prevent retrograde reflux of urine, reducing the risk of complications such as lower back pain and hydronephrosis, and maintaining the convenience and safety of the surgical procedure.
Smart Images
Figure CN224235896U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of ureteral stent technology, and in particular to an anti-reflux ureteral stent. Background Technology
[0002] Kidney stones, ureteral stones, and ureteral strictures of various causes leading to upper urinary tract obstruction and hydronephrosis are common clinically. After the obstruction is relieved following percutaneous nephrolithotomy, ureterolithotomy, or ureteral stricture dilation, doctors usually place a ureteral stent to drain the stones or prevent postoperative ureteral stricture. Although the placement of a ureteral stent delays or prevents further damage to kidney function and facilitates patient recovery, it also presents corresponding post-stent complications, such as bladder irritation and urine reflux. More than 80% of patients experience urine reflux, where urine from the bladder flows back into the ureter and renal pelvis, causing increased intrarenal pressure and leading to complications such as lower back pain, hydronephrosis, and pyelonephritis. Currently, there is no satisfactory solution that can maintain the stent's ability to drain urine while achieving a significant anti-reflux effect. Therefore, there is an urgent need for a ureteral stent that can smoothly drain urine from the renal pelvis and ureter while significantly preventing bladder reflux. Utility Model Content
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an anti-reflux ureteral stent. By setting a hollow expansion section in the bladder segment wall of the stent and integrating a one-way valve composed of multiple valve-like structures inside it, the valve controls the opening and closing of the lumen by automatically opening and closing the leaflets according to the flow direction to achieve one-way drainage. While allowing the guide wire to pass smoothly, it ensures both antegrade drainage from the kidney to the bladder and reliably closes the lumen to prevent retrograde reflux of urine.
[0004] To achieve the above objectives, this utility model provides an anti-reflux ureteral stent, which includes a stent renal pelvis segment, a stent ureteral segment, and a stent bladder segment, wherein the stent ureteral segment connects the stent renal pelvis segment and the stent bladder segment.
[0005] The stent bladder segment has at least one hollow expansion portion on its tube wall;
[0006] An anti-reflux valve is provided inside the lumen of the enlarged part, and the anti-reflux valve includes multiple valve-like structures;
[0007] Each of the multiple lobe-like structures includes a fixed end and a free end;
[0008] The fixed ends of the plurality of petal-shaped structures are all connected to the inner wall of the enlarged portion, and the free ends are all directed toward the distal end of the bladder segment of the stent.
[0009] The free ends of the plurality of valve-like structures are adapted to come together to close the lumen of the stent bladder segment when subjected to fluid pressure from the stent bladder segment toward the stent renal pelvis segment, and to separate to open the lumen when the fluid pressure disappears or when subjected to fluid pressure from the stent renal pelvis segment toward the stent bladder segment.
[0010] Furthermore, two enlarged portions are provided at axial intervals along the bladder segment of the stent.
[0011] Furthermore, the number of the plurality of petal-like structures is three.
[0012] Furthermore, in at least one of the two enlarged portions, the interior of the enlarged portion is provided with three of the petal-shaped structures.
[0013] Furthermore, when the free ends of the plurality of petal-shaped structures are separated by force to open the lumen, the petal-shaped structures abut against the inner wall of the enlarged portion, so that a smooth guide wire channel is formed inside the enlarged portion.
[0014] Furthermore, the fixed ends of the plurality of petal-shaped structures converge at the same point on the inner wall of the enlarged portion.
[0015] Furthermore, the stent renal pelvis segment has multiple first drainage holes on its wall.
[0016] Furthermore, the stent ureter segment is provided with multiple second drainage holes on its wall.
[0017] Furthermore, the free ends naturally converge to partially or completely close the lumen.
[0018] Furthermore, the stent renal pelvis segment is used to be placed in the patient's renal pelvis, the stent ureteral segment is used to be placed in the patient's ureter, and the stent bladder segment is used to be placed in the patient's bladder.
[0019] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:
[0020] (1) Compared to the difficulty and easy failure of installing one-way valves in narrow lumens, or the use of spiral structures that can only dissipate energy, this invention fundamentally solves the problem of urine reflux in ordinary ureteral stents by setting a hollow expansion section and incorporating a multi-leaf one-way valve in the bladder segment of the stent. The valve structure of this invention can actively and completely close the lumen when the bladder pressure increases, and the anti-reflux effect is more direct and reliable. At the same time, its integrated design avoids the stimulation and displacement risks brought by additional components, and achieves a highly efficient and integrated anti-reflux function.
[0021] (2) The unique enlarged structure of this utility model provides ample space for the internal valve-like structure to be fully accommodated when opened, allowing it to fit completely against the inner wall of the tube. This ensures that the guidewire channel remains unobstructed during stent placement or removal, solving the problem that some existing anti-reflux stents increase surgical difficulty and risk due to valve structure interference with guidewire passage. It maintains the same simple clinical operation procedure as traditional stents, while ensuring the convenience and safety of clinical operation.
[0022] (3) In the preferred embodiment of this utility model, two independent valve systems are arranged axially, forming a double redundancy protection, which significantly improves reliability through the dual valve design. Compared with the prior art that relies on a single valve or a single anti-reflux mechanism, this series dual-valve design provides higher safety. Even if one valve fails to close completely due to the influence of small stones or blood clots, the second valve can still effectively prevent urine reflux, thereby greatly improving the reliability of the stent for long-term use in complex physiological environments.
[0023] (4) This utility model preferably uses a valve composed of three lobed structures. Compared with the single-lobed structure, the trilobed valve is more stable in structure and can close symmetrically towards the center point to form a tighter and more reliable seal, thereby effectively preventing leakage. At the same time, this structure can open efficiently under slight pressure from urinary flow, achieving a better balance between ensuring smooth drainage and achieving tight anti-reflux. The trilobed valve structure ensures efficient and stable opening and closing. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the novel anti-reflux ureteral stent structure described in this utility model;
[0025] Figure 2 This is a schematic diagram of the valve-like structure of the novel anti-reflux ureteral stent described in this utility model when closed;
[0026] Figure 3 This is a schematic diagram of the valve-like structure of the novel anti-reflux ureteral stent described in this utility model when the guide wire is passed through it;
[0027] Figure 4 This is a schematic diagram of the valve-like structure of the novel anti-reflux ureteral stent of this utility model, which allows for antegrade drainage of urine.
[0028] Figure 5 This is a schematic diagram of the valve-like structure of the novel anti-reflux ureteral stent of this utility model to prevent retrograde urine reflux;
[0029] Labeling explanation: 1. Stent renal pelvis segment; 2. Stent ureter segment; 3. Stent bladder segment; 4. Guide wire; 5. Urine; 11. First drainage hole; 21. Second drainage hole; 31. Enlarged part; 32. Valve structure. Detailed Implementation
[0030] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.
[0031] In the description of this utility model, it should be understood that the terms "upper," "lower," "horizontal," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0032] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0033] like Figures 1-5 As shown, this embodiment provides an anti-reflux ureteral stent, which includes a stent renal pelvis segment 1, a stent ureteral segment 2, and a stent bladder segment 3, which are sequentially connected to form a passage.
[0034] At least one hollow expansion portion 31 is provided on the wall of the stent bladder segment 3;
[0035] An anti-reflux valve is provided inside the lumen of the enlarged part 31, and the anti-reflux valve includes multiple valve-like structures 32;
[0036] Each of the multiple petal-like structures 32 includes a fixed end and a free end;
[0037] The fixed ends of the multiple petal-like structures 32 are all connected to the inner wall of the enlarged portion 31, and the free ends are all directed toward the distal end of the stent bladder segment 3.
[0038] The free ends of the multiple valve-like structures 32 are adapted to come together to close the lumen of the stent bladder segment 3 when subjected to fluid pressure from the stent bladder segment 3 toward the stent renal pelvis segment 1, and to separate to open the lumen when the fluid pressure disappears or when subjected to fluid pressure from the stent renal pelvis segment 1 toward the stent bladder segment 3.
[0039] This invention, by incorporating a hollow, enlarged portion 31 within the bladder segment 3 of the stent and integrating a one-way valve composed of multiple valve-like structures 32 inside, effectively achieves one-way urine drainage without adding extra components or altering the stent's overall shape. It allows urine to flow antegradely from the kidneys into the bladder and automatically closes the lumen when bladder pressure increases, reliably preventing urine reflux and resolving complications such as lower back pain, hydronephrosis, and infection caused by reflux in existing technologies.
[0040] Furthermore, two bulges 31 are axially spaced along the bladder segment 3 of the stent. The two tandem bulges effectively create a dual-valve system. This design provides redundancy protection; even if one valve fails to completely close, the other valve can still prevent regurgitation, thus greatly improving the stability and reliability of the anti-reflux function.
[0041] Specifically, there are three of the multiple valve-like structures 32, forming a stable tricuspid valve structure. This structure can efficiently open symmetrically towards the center with minimal resistance when subjected to antegrade urine pressure, and can quickly and evenly close towards the center when subjected to retrograde pressure, forming a strong seal that ensures unobstructed drainage and tight anti-reflux properties.
[0042] Furthermore, in at least one of the two enlarged portions, three of the said petal-shaped structures 32 are disposed inside the enlarged portion. This simplifies the structure and saves costs.
[0043] Specifically, when the free ends of the multiple valve-like structures 32 are separated by force to open the lumen, the valve-like structures 32 abut against the inner wall of the enlargement 31, so that a smooth guidewire channel is formed inside the enlargement 31. The design of the enlargement 31 provides sufficient space for the valve-like structures 32 when they open, allowing them to completely abut against the inner wall of the enlargement. This ensures that the guidewire 4 passes through a smooth and unobstructed path when the stent is inserted or removed, maintaining the same inner diameter as a regular stent, avoiding the risk of the guidewire being caught on the valve structure, and simplifying the doctor's clinical operation.
[0044] Furthermore, the fixed ends of multiple petal-shaped structures 32 converge at the same point on the inner wall of the enlarged portion 31. This convergence of the fixed ends of the multiple petal-shaped structures 32 at the same point on the inner wall simplifies the overall valve structure and improves the ease and consistency of the manufacturing process. Simultaneously, this structure ensures that all leaflets can move collaboratively and synchronously, contributing to a more uniform and reliable central closure seal.
[0045] Specifically, multiple first drainage holes 11 are provided in the renal pelvis segment 1 of the stent, so that the stent can collect urine from multiple locations in the renal pelvis, ensuring comprehensive and efficient drainage of the renal urine collection system and avoiding poor drainage and increased intrarenal pressure caused by blockage of a single opening.
[0046] Furthermore, multiple second drainage holes 21 are provided on the wall of the stent ureter segment 2, which further enhances the drainage capacity of the stent. Even if a segment of the ureter becomes edematous or is slightly blocked by stones, urine can still enter the stent lumen through these side holes, ensuring that the drainage pathway from the entire ureter to the bladder remains unobstructed.
[0047] Furthermore, the free ends naturally converge to partially or completely close the lumen, and the valve structure 32 is in a converged or closed state under natural pressure-free conditions, putting the anti-reflux function in a "default on" mode. This allows for complete closure with only a small amount of retrograde bladder pressure, improving the valve's sensitivity to pressure changes and its response speed, making the anti-reflux effect more immediate and effective.
[0048] Specifically, the stent renal pelvis segment 1 is placed in the patient's renal pelvis, the stent ureteral segment 2 is placed in the patient's ureter, and the stent bladder segment 3 is placed in the patient's bladder. By clearly defining the corresponding placement positions of each part of the stent within the body, it ensures that structures with specific functions (such as the fixation structure of the renal pelvis segment and the anti-reflux valve of the bladder segment) can be precisely placed in the correct anatomical locations. This precise positioning is the fundamental guarantee for the stent to safely and effectively perform its dual functions of drainage and anti-reflux.
[0049] The workflow of this utility model is as follows:
[0050] Insertion process: such as Figure 3 As shown, during stent placement, guidewire 4 is inserted through the stent's renal pelvis segment 1, passing through the stent's ureteral segment 2 and bladder segment 3. As guidewire 4 passes through, the valve-like structure 32 opens anterogradely with guidewire 4. After opening, valve-like structure 32 adheres tightly to the inner side of the stent's enlarged portion 31, ensuring a consistent stent diameter and facilitating guidewire 4 exit.
[0051] Forward traffic generation: such as Figure 4As shown, after the stent is successfully placed, the urine 5 in the renal pelvis can flow smoothly into the bladder through the open valve structure 32 along the renal pelvis segment 1 and ureteral segment 2 of the stent, thus realizing the urine flow function of the stent.
[0052] Anti-backflow function: such as Figure 5 As shown, when the bladder contracts due to increased urine volume, the urine attempting to reflux flows into the stent bladder segment 3. The pressure causes the free end of the valve structure 32 to contract and close, thereby sealing the stent lumen and effectively preventing urine from refluxing from the bladder into the ureter and renal pelvis.
[0053] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. An anti-reflux ureteral stent, comprising a stent renal pelvis segment (1), a stent ureteral segment (2), and a stent bladder segment (3), wherein the stent renal pelvis segment (1), the stent ureteral segment (2), and the stent bladder segment (3) are sequentially connected to form a passage, characterized in that, The stent bladder segment (3) has at least one hollow expansion portion (31) on its tube wall; The cavity of the enlarged part (31) is provided with an anti-reflux valve, which includes multiple valve-like structures (32); Each of the multiple petal-like structures (32) includes a fixed end and a free end; Among them, the fixed ends of the multiple petal structures (32) are all connected to the inner wall of the enlarged part (31), and the free ends are all facing the distal end of the stent bladder segment (3); The free ends of the plurality of valve-like structures (32) are adapted to come together to close the lumen of the stent bladder segment (3) when subjected to fluid pressure from the stent bladder segment (3) toward the stent renal pelvis segment (1), and to separate to open the lumen when the fluid pressure is removed or when subjected to fluid pressure from the stent renal pelvis segment (1) toward the stent bladder segment (3).
2. The anti-reflux ureteral stent according to claim 1, characterized in that, Two enlarged portions (31) are provided at axial intervals along the bladder segment (3) of the stent.
3. The anti-reflux ureteral stent according to claim 1, characterized in that, The number of the plurality of petal-like structures (32) is three.
4. The anti-reflux ureteral stent according to claim 2, characterized in that, Of the two enlarged portions, at least one enlarged portion has three of the three petal-shaped structures (32) disposed inside.
5. The anti-reflux ureteral stent according to claim 1, characterized in that, When the free ends of the plurality of petal structures (32) are separated by force to open the lumen, the petal structures (32) abut against the inner wall of the enlarged portion (31) so that a smooth guide wire channel is formed inside the enlarged portion (31).
6. The anti-reflux ureteral stent according to claim 1, characterized in that, The fixed ends of the plurality of petal structures (32) converge at the same point on the inner wall of the enlarged portion (31).
7. The anti-reflux ureteral stent according to claim 1, characterized in that, The stent renal pelvis segment (1) has multiple first drainage holes (11) on its tube wall.
8. The anti-reflux ureteral stent according to claim 7, characterized in that, The stent ureter segment (2) has multiple second drainage holes (21) on its wall.
9. The anti-reflux ureteral stent according to claim 1, characterized in that, The free ends naturally converge to partially or completely close the lumen.
10. The anti-reflux ureteral stent according to claim 1, characterized in that, The stent renal pelvis segment (1) is used to be placed in the patient's renal pelvis, the stent ureter segment (2) is used to be placed in the patient's ureter, and the stent bladder segment (3) is used to be placed in the patient's bladder.