Braided Stent with Opposing Helix Filaments for Radial Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current stent designs, particularly for treating aneurysms, face challenges in balancing structural support and blood flow restriction while minimizing trauma and deformation, especially in complex vascular geometries.
Innovation Solution
A braided stent structure featuring first and second filaments spiraling in opposite directions, with a third stiffer filament extending only in one direction, providing enhanced structural support and blood flow restriction by varying helix angles to optimize expansion and compression without binding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If traditional stent designs are used to provide structural support, then radial strength is improved, but blood flow restriction increases and trauma to vessels worsens
Solution Approach 1:
The stent is divided into multiple struts of varying thicknesses (first, second, and third struts with different cross-sectional dimensions). This segmentation allows different regions to provide different levels of support, with thinner struts reducing blood flow restriction and trauma while thicker struts maintain necessary radial strength in critical areas.
Solution Approach 2:
Different struts are designed with locally optimized properties - first struts have one cross-sectional configuration, second struts have another, and third struts have yet another. This local quality variation enables the stent to provide enhanced radial strength where needed while minimizing blood flow restriction and vessel trauma in other regions through strategically placed thinner struts.
2Strength
If stent expansion is increased to improve vessel support, then radial strength is improved, but deformation and trauma to vessels worsen
Solution Approach 1:
The stent employs a dynamic structure with struts of varying thicknesses that can flex and deform at different rates during expansion. The thinner struts (second and third struts) can deform more easily to accommodate vessel movement and geometry changes, reducing trauma, while thicker first struts maintain overall structural integrity and support.
Solution Approach 2:
The stent functions as a composite structure with struts of different thicknesses and material properties working together. The combination of thicker struts for structural support and thinner struts for flexibility creates a composite system that achieves both strong vessel support and reduced deformation trauma during expansion.
3Ease of manufacture
If stent structure is simplified for easier manufacture, then manufacturing precision is improved, but adaptability to complex vascular geometries worsens
Solution Approach 1:
The stent is segmented into multiple strut types (first, second, and third struts with different configurations) that can be manufactured using standardized processes. Each strut type is designed with specific characteristics for different locations, allowing complex geometries to be achieved through repeated patterns of simpler modular elements rather than requiring entirely custom manufacturing for each unique shape.
Solution Approach 2:
The different strut configurations serve multiple functions - first struts provide primary structural support, second struts reduce blood flow restriction, and third struts provide additional localized support. This multi-functionality allows a single stent design to adapt to various vascular geometries and patient-specific requirements while maintaining manufacturability through standardized production methods for each strut type.
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 braided stent effectively restricts blood flow into aneurysms, promoting clotting while maintaining flexibility and conforming to vessel shapes, reducing the risk of deformation and trauma, and facilitating faster recovery.
Implementation Method 1
Stents may be self-expanding so that they elastically expand out to a preset larger diameter
Implementation Method 2
Self-expanding stents are usually made of shape memory materials or other elastic materials that act like a spring
Data Source
AI summary
A stent is provided with braided filaments. First and second filaments (12, 14) are braided with each other and extend spirally around the stent wall in opposite directions. One or more third filaments (16) are braided with the first filaments (12) and extends spirally around the stent wall only in the direction of the second filaments (14). The third filament (16) is stiffer than the first and second filaments (12, 14), and there are fewer third filaments (16) than the first and second filaments (12, 14).