Adhesive Polymer Coating for Anti-Migration Covered Stents
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stents, particularly fully covered stents, are prone to migration in body lumens due to their compressible and flexible properties, which complicates their deployment and increases the risk of reocclusion and invasive removal procedures.
Innovation Solution
A dissolvable or degradable adhesive polymer is applied to the stent's outer surface, which adheres to the body lumen upon deployment, hindering migration and allowing for removal without invasive procedures by dissolving or degrading over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a stent is made compressible and flexible for delivery, then ease of delivery is improved, but stent migration risk increases
Solution Approach 1:
The adhesive polymer is applied to the stent surface before deployment, creating a tacky coating that will prevent migration once the stent is in place. This preliminary action addresses the migration risk that arises from the necessary flexibility of the stent for delivery.
Solution Approach 2:
The adhesive polymer acts as an intermediary between the stent and the body lumen tissue. It provides the necessary adhesion to prevent migration while allowing the stent to maintain its compressible and flexible properties for delivery. The polymer coating serves as a mediating layer that enables both ease of delivery and migration prevention.
2Ease of repair
If a stent is made fully covered to prevent tissue ingrowth, then ease of removal is improved, but stent migration increases
Solution Approach 1:
The adhesive polymer is applied in advance to the outer surface of the covered stent, providing immediate adhesion upon deployment. This preliminary action counteracts the migration tendency of fully covered stents while maintaining their ease of removal through dissolution or degradation of the adhesive layer.
Solution Approach 2:
The adhesive polymer's properties are designed to change over time - initially providing strong adhesion to prevent migration, then gradually dissolving or degrading to allow for easy removal. This parameter change in the adhesive's structural integrity resolves the contradiction between preventing migration and enabling removal.
3Reliability
If an adhesive polymer is applied to prevent migration, then stent position stability is improved, but device complexity increases
Solution Approach 1:
The adhesive polymer is applied as a thin film or coating on the stent surface, providing migration prevention without significantly increasing the device's structural complexity. The thin film approach maintains the stent's original design while adding the necessary adhesive function.
Solution Approach 2:
The stent system becomes a composite structure combining the stent framework with an adhesive polymer coating. This composite material approach integrates multiple functions (structural support and adhesion) into a single device, preventing migration without requiring separate complex components.
4Ease of repair
If a dissolvable adhesive polymer is used, then ease of removal is improved, but adhesion strength may be reduced
Solution Approach 1:
The adhesive polymer's properties are made dynamic rather than static - it provides strong adhesion initially to prevent migration, then gradually dissolves or degrades to enable removal. This temporal dynamic in adhesion strength resolves the contradiction between maintaining strong bonding and allowing for easy removal.
Solution Approach 2:
The adhesive polymer undergoes parameter changes in its molecular structure over time, transitioning from a strong, intact polymer network to a dissolved or degraded state. This parameter change allows the adhesive to provide strong initial bonding while ultimately enabling easy removal through controlled dissolution or degradation.
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 adhesive polymer effectively prevents stent migration while ensuring easy removal, maintaining the stent's position and reducing the need for invasive procedures.
Implementation Method 1
A dissolvable or degradable adhesive polymer is applied to the stent's outer surface, which adheres to the body lumen upon deployment, hindering migration
Implementation Method 2
the dissolvable adhesive polymer dissolves over time in an aqueous environment
Implementation Method 3
a dissolvable or degradable adhesive polymer... the dissolvable adhesive polymer or the degradable polymer has a surface tack
Data Source
AI summary
A stent having an inner surface and an outer surface, at least a portion of the outer surface of the stent comprising a dissolvable adhesive polymer or a degradable adhesive polymer disposed on at least a portion of the outer surface of the stent, the adhesive is activated by exposure to an aqueous environment, the dissolvable adhesive polymer dissolves over time in an aqueous environment, the dissolvable adhesive polymer or the degradable adhesive polymer has a surface tack of about 2 psi to about 14 psi.