Stent Covering With Polymeric Loops For Tissue Ingrowth

Solution Overview

Problem

Endoprostheses, such as stents, face challenges in preventing migration while minimizing trauma to the body lumen during removal, as bare stents require cutting away ingrown tissue for removal and fully covered stents are prone to migration.

Innovation Solution

A stent covering with polymeric tissue ingrowth features, including loops and hooks, that extend above the surface to allow tissue growth, preventing ingrowth into the stent lumen and facilitating secure placement while enabling easy removal by applying force to detach grown tissue.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If bare endoprosthesis is used to allow tissue ingrowth for preventing migration, then anti-migration capability is improved, but trauma to body lumen during removal worsens

Engineering Contradiction:

Improveanti-migration capabilityVSAvoidtrauma to body lumen

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The endoprosthesis is divided into two functional zones: a proximal uncovered section that allows tissue ingrowth for anchoring and preventing migration, and a distal covered section that provides a smooth surface to minimize trauma during removal. This segmentation allows each zone to perform its specific function independently.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the endoprosthesis are given different surface characteristics: the proximal end has an uncovered, rough surface to promote tissue ingrowth and secure anchoring, while the distal end has a covered, smooth surface to reduce trauma to the body lumen during removal procedures.

Inventive Principle:

Principle #3Local quality

2Ease of operation

If fully covered endoprosthesis is used to prevent tissue ingrowth for facilitating removal, then ease of removal is improved, but anti-migration capability worsens

Engineering Contradiction:

Improveease of removalVSAvoidanti-migration capability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The endoprosthesis is divided into two functional zones: a proximal uncovered section that allows tissue ingrowth for anchoring and preventing migration, and a distal covered section that provides a smooth surface to minimize trauma during removal. This segmentation allows each zone to perform its specific function independently.

Inventive Principle:

Principle #1Segmentation

3Reliability

If bare endoprosthesis is used to allow tissue ingrowth, then anti-migration capability is improved, but device complexity worsens due to tissue management

Engineering Contradiction:

Improveanti-migration capabilityVSAvoidtissue management complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The endoprosthesis is divided into two functional zones: a proximal uncovered section that allows tissue ingrowth for anchoring and preventing migration, and a distal covered section that provides a smooth surface to minimize trauma during removal procedures.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the endoprosthesis are given different surface characteristics: the proximal end has an uncovered, rough surface to promote tissue ingrowth and secure anchoring, while the distal end has a covered, smooth surface to reduce trauma to the body lumen during removal procedures.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS10195061B2Controlled tissue ingrowth stent covering

Publication Date: 2019.02.05 BOSTON SCIENTIFIC SCIMED INC

AI summary

A stent covering includes a polymeric tube having a first end, a second end and a length extending therebetween, the polymeric tube including an inner surface defining a lumen and an outer surface. A plurality of tissue ingrowth features are formed on the outer surface of the polymeric tube, at least some of the plurality of tissue ingrowth features including polymeric loops that extend above the outer surface such that, once implanted, tissue can grow between the outer surface and the polymeric loops. A stent may include such a stent covering.