Proximal-to-Distal Stent Deployment via Lubricous Elastic Membrane
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Solution Overview
Problem
Current stent deployment devices primarily use a distal-to-proximal deployment method, which is undesirable in scenarios requiring precise placement of the stent's proximal edge, such as at the origin of a lumen side branch or overlapping with a previously installed stent, and lacks the capability for pre-defining the stent's position for accurate proximal-to-distal placement.
Innovation Solution
A stent deployment system with an inner and outer catheter, a lubricous elastic membrane, and retractable ring with pull wires, allowing for the precise alignment and deployment of the stent from its proximal end to distal end, enabling accurate placement of the stent's proximal edge within the lumen.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If distal-to-proximal deployment method is used, then deployment simplicity is maintained, but proximal edge placement precision deteriorates
Solution Approach 1:
The patent inverts the conventional deployment sequence by deploying the stent from proximal to distal instead of distal to proximal. The proximal end of the stent is deployed first while the proximal catheter remains stationary, followed by deployment of the distal end. This inversion allows precise positioning of the proximal edge at critical locations such as side branch origins or stent overlaps, while maintaining operational feasibility through the dual-catheter system.
2Manufacturing precision
If proximal-to-distal deployment is implemented, then proximal edge placement precision is improved, but device complexity increases
Solution Approach 1:
The patent segments the stent deployment process into two independent phases: proximal end deployment and distal end deployment. Two separate catheters (proximal catheter and distal catheter) are used to deliver different portions of the stent. This segmentation allows independent control and positioning of each stent end, enabling precise proximal edge placement while managing device complexity through modular catheter design.
Solution Approach 2:
The patent introduces an intermediary mechanism in the form of a pull wire system that connects the distal catheter to the proximal catheter. The pull wire allows the distal catheter to be advanced relative to the proximal catheter, enabling controlled deployment of the distal stent portion after the proximal end is positioned. This intermediary mechanism facilitates the complex proximal-to-distal deployment sequence without requiring a completely new device architecture.
3Manufacturing precision
If proximal edge positioning is pre-defined, then placement accuracy is improved, but deployment flexibility is reduced
Solution Approach 1:
The patent implements a dynamic deployment system where the proximal catheter is initially held stationary to define the proximal stent edge position, but can be moved if needed. The distal catheter can be advanced independently through the pull wire mechanism, allowing the deployment sequence to adapt to different anatomical situations. This dynamic control maintains placement accuracy for the proximal edge while preserving flexibility to adjust the distal end position based on procedural requirements.
Data Source
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AI summary
Methods and devices for delivering a stent in a proximal to distal fashion are disclosed. The delivery device includes a sheath catheter, an outer catheter and an inner catheter over a guide wire. A crimped stent is positioned over the distal end of the outer catheter and is held in place by a lubricous elastic membrane attached to a retractable ring. The retractable ring is connected to pull wires and slidably deployed between the inner and outer catheters. The proximal end of the stent is aligned at the treatment location, and the lubricous elastic membrane is pulled back into the space between inner catheter and outer catheter, releasing and deploying the stent from its proximal to its distal end.