Moveable Fenestration Stent Graft for Branch Vessel Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stent grafts with fenestrations face challenges in accommodating branch vessels, leading to potential blockage and complications due to severe loading conditions and precise alignment requirements, which can impede blood flow and pose risks to patients.
Innovation Solution
An endoluminal prosthesis with a tubular graft body featuring moveable fenestrations created using a second biocompatible graft material that is more flexible than the primary material, allowing for relative movement and alignment with branch vessels, and a method of producing this prosthesis by weaving yarns to form a protrusion with a fenestration, enabling better accommodation of branch vessels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional fixed fenestrations are used in stent grafts, then alignment with branch vessels can be achieved, but severe loading conditions and precise alignment requirements cause deterioration of secondary stents and potential blockage of branch vessels
Solution Approach 1:
The fenestration is made movable relative to the graft body surface plane through a flexible mechanism. This dynamic capability allows the fenestration to adjust its position and orientation to maintain alignment with the branch vessel under pulsatile blood flow conditions, reducing severe loading on the secondary stent while ensuring continuous patency.
Solution Approach 2:
The flexibility parameter of the fenestration interface is changed by introducing a movable mechanism that allows relative movement between the fenestration and the graft body. This parameter change enables the system to adapt to physiological movements and reduce stress concentrations that would otherwise deteriorate the secondary stent.
2Strength
If fixed fenestrations are used in stent grafts, then structural integrity is maintained, but there is little room for error during deployment and precise alignment is required to avoid blocking branch vessels
Solution Approach 1:
The fenestration is designed with movable capability relative to the graft body, allowing it to self-adjust during and after deployment. This dynamic feature provides tolerance for deployment variations while maintaining proper alignment with branch vessels, significantly reducing the precision requirements for the deployment procedure.
Solution Approach 2:
The degree of freedom parameter of the fenestration is changed from fixed to movable, enabling it to accommodate deployment variations. This parameter change transforms the system from requiring precise initial positioning to allowing adaptive positioning, thereby easing operational requirements.
3Adaptability or versatility
If a second biocompatible graft material with different characteristics is used around the fenestration, then flexibility and movement capability are improved, but device complexity increases
Solution Approach 1:
A second biocompatible graft material with different characteristics is applied locally around the fenestration area rather than throughout the entire graft. This localized application provides the necessary flexibility and movement capability at the critical fenestration interface while maintaining the structural integrity of the main graft body, thus limiting the increase in device complexity.
Solution Approach 2:
The graft is constructed as a composite structure with a first biocompatible material for the main body and a second biocompatible material with different characteristics around the fenestration. This composite construction allows optimization of each region for its specific function while maintaining overall system integrity.
Data Source
AI summary
An endoluminal prosthesis with a moveable fenestration including a tubular graft body having a proximal end, a distal end, a surface plane at least one fenestration having a perimeter disposed in a sidewall of the tubular body between the proximal end and the distal end, a first biocompatible graft material, and a second biocompatible graft material adjacent to and surrounding the perimeter of the at least one fenestration. The second biocompatible graft material has at least one characteristic different from the first biocompatible graft material and is more flexible than the first biocompatible graft material and is movable relative to the surface plane of the tubular graft body.