Stent Wire Radiopacity via Drawn Fill Tube Composite
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vascular prostheses, such as stents, face challenges in visualization and deployment due to the need for radiopaque markers, which can increase the profile and stiffness, making it difficult to conform to tortuous anatomical sites and maintain proper apposition within the vasculature.
Innovation Solution
The use of drawn filled tube wires (DFT wires) with a radiopaque inner core and a flexible shape memory alloy outer jacket, combined with pre-shaped connecting wires, allows for improved visualization and flexibility, reducing the need for additional markers and enhancing the stent's ability to expand and anchor within the vasculature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Difficulty of detecting and measuring
If radiopaque markers are added to stents for visualization, then visibility under radiography is improved, but the profile and stiffness increase making it difficult to conform to tortuous vessels
Solution Approach 1:
The patent combines the radiopaque marker function with the structural wire itself by incorporating radiopaque material into the stent wire composition. This integration eliminates the need for separate radiopaque marker components while maintaining visualization capability and preserving the wire's flexibility and conformability to tortuous vessels.
Solution Approach 2:
The patent employs composite materials by creating stent wires with radiopaque material embedded within or coated on the structural wire. This composite construction provides both the radiopacity needed for visualization and the mechanical properties required for vessel conformability, resolving the contradiction between visibility and adaptability.
2Difficulty of detecting and measuring
If radiopaque markers are added to stents for visualization, then visibility under radiography is improved, but the stent stiffness increases making deployment difficult
Solution Approach 1:
The patent merges the radiopaque marker function with the structural wire by incorporating radiopaque material into the wire composition. This integration maintains visualization capability while avoiding the stiffness increase associated with separate rigid marker components, as the radiopaque material is distributed throughout the wire structure.
Solution Approach 2:
The use of composite materials with radiopaque components integrated into the wire matrix provides visualization without significantly increasing overall stent stiffness. The radiopaque material is distributed in a way that maintains the wire's flexibility and deployability while enabling radiographic detection.
3Quantity of substance
If DFT wires with radiopaque inner core are used, then visualization is improved and marker quantity is reduced, but manufacturing complexity increases
Solution Approach 1:
The patent combines multiple functions (structural support and radiopacity) into a single integrated wire component. This merging reduces the total quantity of radiopaque material needed while improving visualization, and although it increases manufacturing complexity, the integrated design simplifies assembly by eliminating separate marker components.
Solution Approach 2:
The composite wire structure with radiopaque inner core and flexible outer jacket creates a multi-functional component that reduces the number of separate radiopaque markers needed. The manufacturing complexity increase is offset by the elimination of separate marker assembly steps and the reduction in total radiopaque material quantity.
Data Source
AI summary
A vascular implant may comprise at least a first layer having one or more drawn fill tube wires (DFT wires) and at least a second layer having one or more non-DFT wires. The first layer may be braided from only a single DFT wire, and the second layer may be braided from a plurality of non-DFT wire. A vascular implant may also include a connecting wire composed of a shape memory alloy and that is shape set prior to connection to one or more implant layers composed of DFT wires.