Polymeric Stent Radiopaque Marker Structural Integration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Bioresorbable polymer stents face challenges in visibility under fluoroscopy due to low radiopacity, making accurate positioning difficult, especially in patients with larger mass or with suboptimal equipment, and increasing the number of radiopaque markers does not significantly improve visibility.

Innovation Solution

Incorporating radiopaque markers made of materials with higher radiopacity than the polymer substrate, strategically positioned to connect rings or link struts, ensuring their elimination results in a complete structural break, maintaining axial distance and structural integrity through retainers and surface coatings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Difficulty of detecting and measuring

If metallic radiopaque markers are attached to polymer stents to improve visibility under fluoroscopy, then visibility is improved, but structural integrity and mechanical strength are compromised

Engineering Contradiction:

Improvevisibility under fluoroscopyVSAvoidstructural integrity

Core Design Contradiction:

Difficulty of detecting and measuringVSStrength

Solution Approach 1:

The patent applies composite materials by integrating radiopaque particles directly into the polymer matrix of the stent struts, creating a homogeneous composite structure. This eliminates the need for separate metallic markers while maintaining both visibility and structural integrity, as the radiopaque material becomes an integral part of the load-bearing polymer structure rather than an attached component.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent merges the function of structural support and radiopacity into a single integrated component. The radiopaque marker and stent strut are combined into one unified structure where the radiopaque material is distributed within the polymer matrix, eliminating the distinction between structural element and radiopaque marker that exists in conventional designs.

Inventive Principle:

Principle #5Merging (Combining)

2Difficulty of detecting and measuring

If the number of radiopaque markers is increased to improve visibility, then visibility is improved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:

Improvevisibility under fluoroscopyVSAvoidnumber of radiopaque markers

Core Design Contradiction:

Difficulty of detecting and measuringVSDevice complexity

Solution Approach 1:

The patent applies local quality by concentrating radiopaque material specifically within the strut structures that are visible under fluoroscopy, rather than distributing discrete markers throughout the entire stent. This creates localized radiopacity where it is most needed for visualization while maintaining a simpler overall device architecture with fewer distinct components.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

By using composite materials with radiopaque particles embedded in the polymer, the patent eliminates the need for multiple separate radiopaque marker components. The radiopacity is achieved through the material composition itself rather than through the assembly of multiple discrete markers, significantly reducing device complexity.

Inventive Principle:

Principle #40Composite materials

3Difficulty of detecting and measuring

If radiopaque markers are attached to polymer stents, then visibility is improved, but manufacturing precision and alignment accuracy deteriorate

Engineering Contradiction:

Improvevisibility under fluoroscopyVSAvoidmarker positioning accuracy

Core Design Contradiction:

Difficulty of detecting and measuringVSManufacturing precision

Solution Approach 1:

The patent merges the radiopaque marker function with the stent strut manufacturing process itself. Since the radiopaque material is embedded within the polymer matrix during strut formation, the positioning accuracy is determined by the strut geometry and material distribution rather than by separate attachment operations, eliminating alignment and positioning errors associated with attaching discrete markers.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The use of composite materials allows radiopaque particles to be incorporated into the polymer during the extrusion or molding process that forms the struts. This integration ensures precise and consistent positioning of radiopaque material within the strut structure, eliminating the manufacturing variability and alignment issues that arise from attaching separate marker components.

Inventive Principle:

Principle #40Composite materials

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

Enhances the visibility of bioresorbable polymer stents under fluoroscopy without compromising mechanical strength or structural integrity, allowing for more accurate placement and minimizing disruption in blood flow.

Implementation Method 1

a radiopaque marker made of a material having a radiopacity greater than that of the polymer substrate material

Methodology Applied

Scientific EffectX-ray absorption: Absorption (EM radiation)

Data Source

PatentUS10098764B2Polymeric stent with structural radiopaque marker

Publication Date: 2018.10.16 ABBOTT CARDIOVASCULAR SYSTEMS INC

AI summary

An implantable sent comprises a radiopaque marker that provides a structural connection between two parts made of a polymer substrate material. The two parts can be one bending element of one radially expandable ring and another bending element of an adjacent expandable ring. The two parts can be two bending elements of the same radially expandable ring. The radiopaque marker can be in the form of an entire radially expandable ring.