Stent With ECM Coating and Microporous Voids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current medical stents face challenges in maintaining luminal patency while minimizing migration and allowing for removability, as they either experience tissue ingrowth leading to re-occlusion or migration issues due to coating and design limitations.
Innovation Solution
A stent design featuring a micropatterned surface with protrusions and voids coated with an extracellular matrix material, which acts as a mucosal adhesive to secure the stent initially and promote tissue ingrowth for long-term anchorage, while being bioabsorbable to facilitate removal without trauma.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a stent is coated with adhesive material to prevent migration, then migration is reduced, but tissue ingrowth may lead to re-occlusion
Solution Approach 1:
The stent surface is segmented into multiple functional layers: a microporous polymer coating layer and an outer extracellular matrix layer. This segmentation allows the inner layer to provide adhesive anchorage while the outer layer controls tissue interaction, preventing harmful tissue ingrowth that causes re-occlusion while maintaining reliable stent positioning.
Solution Approach 2:
The stent coating applies local quality by providing different properties at different depths: the microporous polymer layer provides adhesive properties for initial anchorage, while the outer extracellular matrix layer provides a controlled interface for tissue interaction. This localized differentiation allows simultaneous achievement of secure anchorage and prevention of harmful tissue ingrowth.
2Reliability
If a stent uses a coating to maintain luminal patency, then patency is improved, but the stent becomes difficult to remove without trauma
Solution Approach 1:
The coating materials are selected to be bioabsorbable, meaning their physical and chemical properties change over time through controlled degradation. The extracellular matrix layer and microporous polymer layer gradually break down into biocompatible products, allowing the stent to be removed without trauma while maintaining luminal patency during the absorption period.
Solution Approach 2:
The bioabsorbable coating acts as a temporary, disposable protective layer that fulfills its function of maintaining luminal patency and providing anchorage, then degrades completely. This allows the underlying stent to be removed without trauma, as the coating no longer provides adhesive resistance after degradation.
3Ease of manufacture
If a stent uses traditional coating methods, then manufacturing is simple, but the stent cannot simultaneously achieve migration prevention and removability
Solution Approach 1:
The stent employs a composite coating structure consisting of a microporous polymer coating layer and an outer extracellular matrix layer. This composite structure can be applied using conventional dip-coating or spray-coating methods, maintaining manufacturing simplicity while providing the dual functionality of initial adhesive anchorage and subsequent bioabsorbable degradation for trauma-free removal.
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 stent effectively reduces migration and allows for tissue ingrowth to maintain patency, while being removable without causing trauma, addressing the limitations of existing stent designs.
Implementation Method 1
an extracellular matrix material coating disposed over the polymeric covering and within the plurality of voids
Implementation Method 2
applying a liquid extracellular matrix hydrogel over the polymeric covering and drying the extracellular matrix hydrogel to form an extracellular matrix material
Data Source
AI summary
An implantable medical device may comprise an elongated tubular body having a scaffolding forming a plurality of cells. A polymeric covering may be disposed over at least a portion of the stent. The covering may include a plurality of voids formed in an outer surface thereof. An extracellular matrix material coating may be disposed over the polymeric covering and within the plurality of voids.