Biodegradable Double-J Stent Preventing Ureteral Obstruction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional double-J stents often remain in place for too long, leading to encrustation and kidney stone formation, causing ureteral obstruction, hydronephrosis, and potential renal failure due to forgetfulness in timely removal.
Innovation Solution
A biodegradable double-J stent made from materials like extracellular matrix-derived materials or pure collagen, with varying degradation rates for different components and a hydrophilic lubrication layer to facilitate insertion and reduce friction, and a radiopaque contrast agent for visibility, ensuring spontaneous degradation and preventing obstruction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional double-J stent is placed in the ureter for long-term use, then it provides continuous urinary drainage and prevents hydronephrosis, but encrustation and kidney stone formation occur leading to ureteral obstruction
Solution Approach 1:
The patent applies parameter changes by transitioning from a permanent non-degradable stent to a biodegradable stent that changes its material properties over time. The stent gradually degrades from a solid structural support to complete decomposition, changing the parameter of material persistence from indefinite to controlled degradation period, thereby preventing long-term encrustation while maintaining initial drainage function
Solution Approach 2:
The patent implements the disposable principle by designing a single-use biodegradable stent that performs its function temporarily and then degrades naturally in the body. This eliminates the need for removal surgery and prevents the harmful effects of long-term indwelling, as the stent is intentionally designed with limited lifespan to match the treatment period
2Duration of action of moving object
If a double-J stent is left in place for an extended period, then it maintains urinary flow, but forgotten removal leads to severe complications including renal failure
Solution Approach 1:
The biodegradable stent is designed with inherent limited lifespan, automatically eliminating the need for patient or physician intervention for removal. The stent's material composition ensures it degrades after a predetermined period, making the removal process foolproof and eliminating the risk of forgotten retention
Solution Approach 2:
The stent performs self-removal through biodegradation, eliminating the need for external intervention. The material automatically breaks down and is absorbed or excreted by the body, making the removal process autonomous and independent of human memory or scheduling
3Object-generated harmful factors
If a biodegradable material is used for the stent, then spontaneous degradation prevents obstruction, but the mechanical strength decreases over time
Solution Approach 1:
The patent manages the time-dependent parameter changes of biodegradable materials by selecting materials and formulations that maintain adequate mechanical strength during the required functional period, then progressively degrade. The degradation rate is controlled to match the treatment duration, ensuring strength is sufficient when needed and decreases only after the stent has fulfilled its drainage function
Solution Approach 2:
The stent may have non-uniform material composition or structure in different regions, with some areas designed to degrade faster than others. This local differentiation allows critical structural regions to maintain strength longer while non-critical regions degrade earlier, optimizing the balance between mechanical support and degradation timing
4Ease of operation
If a lubrication layer is added to the stent, then insertion ease and friction reduction improve, but device complexity increases
Solution Approach 1:
The stent is constructed as a composite structure combining the biodegradable base material with a lubrication coating layer. This composite approach integrates the lubrication function directly into the stent structure, providing smooth insertion and reduced friction without requiring separate lubrication mechanisms or additional components
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The biodegradable double-J stent effectively prevents ureteral obstruction by degrading over time, reducing mechanical strength, and enhancing visibility under X-ray, thus addressing the issues of encrustation and stone formation associated with conventional stents.
Implementation Method 1
a biodegradable double-J stent made of a biodegradable material with biocompatibility
Implementation Method 2
the biodegradable material for double-J stent is selected from either extracellular matrix-derived material or pure collagen
Implementation Method 3
a lubrication layer made of a biocompatible, hydrophilic material
Implementation Method 4
the lubrication layer is coated on: (i) the main tube, the first retaining tube, and the second retaining tube
Implementation Method 5
a contrast agent made of a biocompatible radiopaque material, wherein the contrast agent is coated on: (i) the main tube, the first retaining tube, and the second retaining tube
Data Source
AI summary
A biodegradable double-J stent and a method of manufacturing a biodegradable double-J stent are provided. The stent comprises a main tube, a first retaining tube, and a second retaining tube, each fabricated from a biodegradable material. The first and second retaining tubes are curl-shaped and are connected to two ends of the main tube, respectively. The method of manufacturing a biodegradable double-J stent comprises the steps of: (a) providing a tube made of a biodegradable material; and (b) bending two ends of the tube to render the two ends curl-shaped and keeping a middle segment between the two ends straight. The two curl-shaped ends define a first retaining tube and a second retaining tube, respectively, and the middle segment defines a main tube. The biodegradable double-J stent precludes a ureteral obstruction which might otherwise occur with conventional double-J stents not removed in a timely manner.