Stenting Ring Marker Nested Within Strut Radial Envelope
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stenting rings face a challenge in balancing stent flexibility and deployment force while maintaining precise marker visibility, as existing markers often interfere with delivery and deployment due to their size and placement, and current designs compromise between visibility and stent performance.
Innovation Solution
A marker with a radial thickness less than the stent ring, overlapping with struts of smaller radial thickness, is used, allowing for precise placement without increasing the stent's radial thickness, combined with advanced laser cutting techniques to create secure, frusto-conical joining surfaces and precise bonding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the marker is made bigger to improve radiologist visibility, then the marker visibility is improved, but the stent delivery and deployment performance deteriorates
Solution Approach 1:
The marker is positioned in a radial dimension that overlaps with the struts rather than extending axially beyond the stent ends. This dimensional repositioning allows the marker to be visible in x-ray images while not interfering with the stent's delivery through narrow tortuous lumens or its deployment at the stenting site.
Solution Approach 2:
The marker is nested within the radial space occupied by the struts, with the marker thickness being less than the characteristic wall thickness of the stent ring. This nesting allows the marker to be contained within the stent's radial envelope, eliminating the need for larger delivery systems while maintaining visibility.
2Adaptability or versatility
If the radial thickness of the stent annulus is reduced to improve flexibility for transluminal delivery, then the flexibility is improved, but the stenting force deteriorates
Solution Approach 1:
The struts are designed with non-uniform radial thickness, being thinner at the ends and thicker in the middle section. This local variation in thickness allows the stent to maintain high flexibility at the ends for navigation through tortuous lumens while providing sufficient stenting force in the middle section where it is needed for vessel support.
3Measurement precision
If the marker thickness is increased to improve visibility, then the marker visibility is improved, but the radial thickness of the stent annulus increases
Solution Approach 1:
The marker thickness is set to be less than the characteristic wall thickness of the stent ring, providing sufficient radiopacity for visibility while deliberately avoiding the excessive thickness that would interfere with delivery. This partial thickness is adequate for the marker's visibility function without compromising stent performance.
Data Source
AI summary
A stenting ring made of a tube or rolled-up sheet that has a characteristic wall thickness. The ring defines a lumen and is equipped with at least one marker made of a material different from that of the ring. The ring is expansible from a radially compact disposition with a relatively small circumference to a radially expanded disposition with a relatively large circumference. The ring exhibits in the compact disposition a serpentine arrangement of succeeding struts lying in alternate opposite directions to the longitudinal axis of the lumen. The marker has a thickness in the radial direction of the ring that is less than the characteristic wall thickness, and has a width that extends circumferentially around an arc of the ring. The marker is attached to the ring at a zone located at a point intermediate in the extent of said arc. The marker overlaps with a respective one of said struts, at each end of its circumferential arc, when the ring is in the compact disposition, the respective struts moving away from each other, and from the marker, when the ring expands towards said radially expanded disposition.