Alternating Annular Stent Segments for Tortuous Vessel Trackability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing in-vivo stents face challenges with insufficient expansion force and trackability, particularly in tortuous blood vessels, leading to complications such as thrombus formation and damage to the blood vessel wall.
Innovation Solution
The development of an in-vivo indwelling stent with a design featuring alternately arranged first and second pattern annular bodies, connected by curved connection portions, which provides excellent radial compression retractability and blood vessel trackability, ensuring a satisfactory vasodilating effect.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a stent with conventional design is used, then the stent can be inserted into the blood vessel, but the expansion force is insufficient and trackability is poor in tortuous blood vessels
Solution Approach 1:
The stent is divided into multiple annular bodies (first and second pattern annular bodies) that are alternately arranged and connected by connection portions. This segmentation allows each annular body to contribute to expansion force while the connection portions provide flexibility for trackability in tortuous vessels.
Solution Approach 2:
The connection portions are designed with curved shapes that allow the stent to follow the curvature of tortuous blood vessels. The alternating first and second pattern annular bodies create a flexible structure that can navigate complex vascular geometries while maintaining expansion capability.
2Ease of operation
If a stent is placed in a tortuous blood vessel, then the stent can reach the target site, but buckling occurs and stent strut enters the lumen causing thrombus formation
Solution Approach 1:
The stent structure with alternately arranged first and second pattern annular bodies connected by curved connection portions creates a dynamic, flexible configuration that adapts to vessel curvature. This reduces buckling and prevents stent struts from entering the lumen, thereby reducing thrombus formation risk.
3Strength
If a stent is expanded at the target site, then the lumen is maintained, but the stent may damage the blood vessel wall causing perforation or injury
Solution Approach 1:
The segmented structure with multiple annular bodies provides distributed support that maintains lumen patency while reducing localized stress concentration on the vessel wall. This segmentation allows for more uniform force distribution during expansion.
4Reliability
If antithrombotic therapy is continued after surgery, then thrombus risks are reduced, but the brain has poor medication accessibility due to the blood-brain barrier
Solution Approach 1:
The stent structure itself is designed to minimize thrombus formation through its excellent trackability and smooth strut configuration that prevents buckling and lumen encroachment. This self-service approach reduces reliance on pharmacological intervention that is limited by the blood-brain barrier.
Data Source
AI summary
This in-vivo indwelling stent has annular bodies constituted by a plurality of annular bodies arranged in the axial direction, and connection portions. The plurality of annular bodies includes first pattern annular bodies and second pattern annular bodies that are alternately arranged. The first pattern annular bodies each have an endless zigzag linear shape including one-end-side apexes, other-end-side apexes, and curved linear bodies that connects the apexes and protrudes in a first circumferential direction. The second pattern annular bodies each have an endless zigzag linear shape including one-end-side apexes, other-end-side apexes, and a plurality of curved linear bodies that connects the apexes and protrudes in a second circumferential direction. The one-end-side apex and the other-end-side apex of adjacent annular bodies are connected to each other with the connection portion.