Stent Expandable Elements Plastic Deformation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stents have limited expandability, requiring frequent replacements as patients grow, especially in pediatric cases, due to small initial vessel sizes and limited maximum cross-sectional expansion, leading to repeated invasive procedures.
Innovation Solution
The stent design incorporates geometrically unique expansion elements with varying directions and material properties that allow for significant plastic stretching, enabling a wider range of expansion from 2 mm to 18 mm, including zigzag and spiral configurations, and a predetermined breaking point for controlled expansion, allowing the stent to adapt to growing vessel sizes without needing replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional stents with fixed maximum expansion size are used, then the stent provides stable structural support, but the stent must be replaced frequently as patients grow
Solution Approach 1:
The stent incorporates expansion elements with variable geometry that allow the stent to dynamically change its cross-sectional dimensions. The expansion elements can be progressively activated to achieve multiple expansion stages (e.g., 2mm to 18mm diameter), transforming a static structure into a dynamic one that adapts to growing vessel sizes over time
Solution Approach 2:
The stent is divided into functional segments including expandable elements with different geometric configurations (zigzag, spiral patterns). These segmented expansion elements can be independently activated or combined to achieve different expansion levels, allowing progressive adaptation to vessel growth without requiring complete stent replacement
2Adaptability or versatility
If stents are designed for small initial vessel sizes, then the stent fits pediatric patients, but the stent reaches maximum expandability quickly and requires replacement
Solution Approach 1:
The stent is pre-configured with multiple expansion elements and geometric patterns that anticipate future vessel growth. The expansion elements are designed in advance to provide progressive expansion capabilities, allowing the stent to accommodate vessel growth from childhood through adulthood without replacement by activating additional expansion stages as needed
3Adaptability or versatility
If stents are designed with large maximum expansion, then the stent covers growth from childhood to adulthood, but the stent requires large initial cross-section which is not suitable for small vessels
Solution Approach 1:
The stent transitions from a static large-diameter design to a dynamic structure that starts with a small contracted cross-section suitable for pediatric vessels and progressively expands to large diameters for adult vessels. The expansion elements enable controlled progressive enlargement from 2mm to 18mm diameter, adapting to vessel growth rather than requiring a large initial size
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
This design allows for a much larger cross-sectional expansion range, potentially covering growth from childhood to adulthood, reducing the need for multiple stent replacements and minimizing invasive procedures by providing a stable vascular support.
Implementation Method 1
the material, thickness and web width of the expansion element are selected in such a way that by introducing force in the radial direction of the tubular implant, the expansion element can be brought into a permanently expanded state by plastic stretching
Data Source
Figure 1a~1c
Figure 1d
Figure 2
AI summary
The invention relates to a stent that can be implanted and redilated and that is tubularly constructed from elongate webs (11, 11', 11'') that form a wall of the implant, the webs being plastically deformable in such a way that the implant (10) remains permanently widened in the expanded state in the radial direction transverse to the longitudinal axis of the webs. The stent is characterized in that at least one of the webs (11) has an expandable element (12, 12'), which forms a web section within said web (11), in which web section the expandable element extends partially geometrically and transversely to the longitudinal axis of the web in the contracted state, wherein the course of the expandable element has several direction changes relative to said longitudinal axis. The stent is further characterized in that the material, thickness, and web width of the expandable element are selected in such a way that by applying force in the radial direction of the tubular implant, the expandable element can be put into a permanently expanded state by means of plastic elongation, in which permanently expanded state the web section that forms the expandable element has a greater geometric extent transversely to the longitudinal axis and a smaller extent in the direction of the longitudinal axis than in the contracted state. The expandability of the stent is thus increased considerably.