Helical Stent With Segmented Ends For Tortuous Vessels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stents face challenges in navigating tortuous anatomy and maintaining patency in vessels while being deliverable through small profiles, requiring enhanced flexibility and adaptability.
Innovation Solution
The design incorporates a helical winding stent with varying undulations and a coupling portion, along with distinct end and intermediate portions, to provide flexibility and maintain patency, featuring a tubular structure with struts and bridges that allow for self-expansion and navigation through tortuous vessels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a stent is designed with a rigid structure to maintain patency in vessels, then it can provide structural support, but it becomes difficult to navigate tortuous anatomy and deliver through small profiles
Solution Approach 1:
The stent is divided into multiple interconnected rings with connecting linkages, creating a modular structure that can flex and adapt to tortuous anatomy while maintaining overall structural integrity for patency support
Solution Approach 2:
The stent employs a dynamic lattice framework where rings and linkages can relative move against each other, allowing the structure to conform to irregular vessel paths during delivery while providing rigid support once deployed
2Adaptability or versatility
If a stent is made highly flexible to navigate tortuous anatomy, then it can adapt to vessel geometry, but it may lack the structural strength to maintain patency
Solution Approach 1:
The segmented ring structure allows localized flexibility at connection points while maintaining overall structural coherence, enabling the stent to bend and adapt without compromising the structural integrity needed for patency maintenance
Solution Approach 2:
The stent utilizes composite construction combining flexible connecting linkages with stronger ring structures, creating a hybrid framework that simultaneously provides adaptability and structural strength
3Ease of operation
If a stent uses a simple lattice structure for easy delivery, then it can be compressed to small profiles, but it may insufficiently maintain appropriate longitudinal spacing between rings
Solution Approach 1:
The segmented design with discrete rings and linkages allows the stent to be compressed segment by segment during delivery, while the connecting linkages maintain controlled longitudinal spacing between rings even in the compressed state
Solution Approach 2:
The dynamic connection between rings allows the structure to transition from a compressed low-profile state during delivery to an expanded state with maintained longitudinal spacing once deployed in the vessel
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 stent effectively adapts to tortuous anatomy, ensuring patency and easy delivery through small profiles, with enhanced flexibility and mechanical stability, reducing distortion and interference during expansion and compression.
Implementation Method 1
The most common metal alloy utilized by these examples is Nitinol, which has strong shape memory characteristics so that the Nitinol self-expands when placed in the duct or vessel of a mammalian body at normal body temperature.
Data Source
Figure 1A~1B
Figure 1C
Figure 1D
AI summary
Preferred embodiments of an implantable medical device with a high degree of flexibility is shown and described. One aspect includes an implantable stent (100) having an intermediate portion (14) with a helical winding and first (10) and second (12) end portions. The implantable stent further includes a coupling portion (15) with a helical winding, and bridges (26a) joining struts of defining the helical windings. The stent also includes a paddle (19a) providing a bridge (18a) joining the ends of the helical windings. Another aspect relates to a radially self-expansible stent with a plurality of radiopaque markers (20a) attached to it. The markers are shaped and located at the stent end such that the compressive stress exerted on the end.annulus of the stent during release of the stent is shared between the markers and the inflection zones that do not carry a marker.