Migration Resistant Stent Graft with Segmented Sealing Gasket
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current stent grafts for treating abdominal aortic aneurysms face challenges such as migration, lack of flexibility, and interference with renal blood flow due to their design, which affects their stability and deployment.
Innovation Solution
A prosthetic vascular stent graft with a sealing gasket made from shape memory materials like Nitinol, featuring a cylindrical stent segment with a framing bracket that divides into two portions for graft legs, inward and outward barbs for securement, and a compressible foam to prevent blood leakage, allowing for individual deployment and improved flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a stent graft uses a long circumferential stent structure for supra-renal stabilization, then positional stability is improved, but flexibility and renal blood flow are compromised
Solution Approach 1:
The stent graft is divided into multiple modular segments including a sealing gasket portion, a stabilizer portion, and framing brackets that can be independently deployed. This segmentation allows each component to perform its specific function - the stabilizer provides anchoring while the graft legs maintain flexibility for renal artery patency.
Solution Approach 2:
The framing bracket extends in the radial dimension from the stent segment, creating a three-dimensional structure that provides stabilization without requiring excessive longitudinal length. This dimensional transition allows the stabilizing function to be achieved perpendicular to the main stent axis, preserving flexibility along the longitudinal axis.
2Stability of the object's composition
If a stent graft uses a long circumferential stent structure for supra-renal stabilization, then positional stability is improved, but renal blood flow is obstructed
Solution Approach 1:
The stent graft is divided into multiple modular segments including a sealing gasket portion, a stabilizer portion, and framing brackets that can be independently deployed. This segmentation allows each component to perform its specific function - the stabilizer provides anchoring while the graft legs maintain flexibility for renal artery patency.
Solution Approach 2:
Different portions of the stent graft have specialized local properties - the stabilizer portion has rigid circumferential structure for anchoring, while the graft leg portions have flexible, open architectures specifically designed to maintain renal artery patency. Each segment's structure is optimized for its local function.
3Ease of operation
If a stent graft is designed for percutaneous insertion, then ease of deployment is improved, but positional stability after deployment may be compromised
Solution Approach 1:
The stent graft components are nested within a delivery catheter during percutaneous insertion. The sealing gasket, stabilizer, and graft legs are crimped together in a compressed state within the delivery system, allowing minimally invasive insertion through the femoral artery. Upon deployment, the nested structure expands to its final configuration with all stabilization features engaged.
Solution Approach 2:
The stent graft is pre-assembled in a compressed, deliverable state within the catheter system before insertion. The framing brackets and stabilizer components are pre-positioned to engage with the vessel wall and iliac arteries immediately upon deployment, ensuring positional stability is achieved as part of the deployment process itself rather than requiring separate stabilization steps.
4Reliability
If a stent graft uses barbs for securement, then migration resistance is improved, but vessel wall damage may increase
Solution Approach 1:
The barbs are localized to specific regions of the stent graft - primarily on the framing brackets and stabilizer portion that contact the vessel wall and iliac arteries. The graft leg portions that contact the renal arteries have smoother surfaces to minimize damage while maintaining patency. Each region's surface properties are optimized for its specific functional requirements.
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 solution enhances positional stability, reduces migration, and maintains adequate blood flow to renal arteries by providing superior flexibility and secure attachment, addressing the limitations of existing stent grafts.
Implementation Method 1
Structure of the sealing gasket preferably comprises a shape memory material, more preferably Nitinol and/or an alloy comprising Nitinol
Data Source
AI summary
A prosthetic stent graft for the treatment of AAA includes a plurality of graft legs, each secured in a deployed position by a sealing gasket within a stent segment of the sealing gasket and to one side of a framing bracket. The framing bracket traverses the diameter of the stent segment and extends axially away, dividing the first stent segment into two portions, each portion for receiving a graft leg of the stent graft. The sealing gasket can include a stabilizer having a second generally cylindrical stent segment, and an extension bracket traversing the diameter of the second stent segment and extending away from the second stent segment. The extension bracket and the first bracket are connected with one another at a mutual generally central position.