Stent Delivery Core Assembly Compression Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stent delivery systems are susceptible to compression and elongation during navigation through a catheter, which can alter the performance characteristics such as flexibility, column strength, and navigability, leading to reduced responsiveness during operation.
Innovation Solution
A core assembly comprising a longitudinally extending wire with a helically cut tube affixed at proximal and distal portions to prevent compression or elongation, ensuring consistent performance and improved navigability through tortuous vasculature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional stent delivery system is used, then the system can be inserted into the vascular system, but the core member is susceptible to compression and elongation during navigation, altering performance characteristics
Solution Approach 1:
The core member is segmented into a proximal wire portion and a distal tube portion, with the tube affixed to the wire at specific locations. This segmentation allows the wire to provide dimensional stability while the tube provides flexibility and navigability, resolving the contradiction between reliability and compositional stability.
Solution Approach 2:
The core member functions as a composite structure combining a wire (providing tensile strength and dimensional stability) with a tube (providing flexibility and navigability). This composite approach allows simultaneous achievement of performance consistency and resistance to compression/elongation.
2Ease of operation
If the core member is made more flexible to improve navigability, then navigation through tortuous vasculature is easier, but the system becomes more susceptible to compression and elongation
Solution Approach 1:
By dividing the core member into wire and tube segments with selective affixing, the distal tube portion can bend and navigate tortuous vessels while the proximal wire portion maintains dimensional stability. This segmentation allows flexibility for navigation without sacrificing overall reliability.
Solution Approach 2:
Different portions of the core member have different mechanical properties: the distal tube portion is more flexible for navigation, while the proximal wire portion is stiffer for stability. This local differentiation of properties resolves the contradiction between ease of operation and reliability.
3Adaptability or versatility
If the tube is made thinner to reduce profile, then the delivery system can access smaller vessels, but the tube becomes more prone to compression and elongation
Solution Approach 1:
The thin-walled tube is combined with the wire to form a composite core member. The tube provides access to small vessels with its thin profile, while the wire provides the necessary strength and resistance to compression, resolving the contradiction between adaptability and strength.
Solution Approach 2:
The tube is affixed to the wire in advance during manufacturing, creating a pre-reinforced structure. This preliminary action ensures that even thin-walled tubes maintain sufficient strength and compression resistance when navigating through the vascular system.
Data Source
Figure 1
Figure 2A~2B
Figure 3~5
AI summary
A stent delivery system can include a core assembly sized for insertion into a corporeal lumen and configured for advancing a stent toward a treatment location in the corporeal lumen. The core assembly can include a longitudinally extending tube having a lumen and a helical cut extending along the tube. An elongate wire can extend through the tube lumen. The wire can have an intermediate portion disposed distal to the tube. The system can also include a stent carried by the intermediate portion.