Spring-Actuated Stent Delivery Sheath Retraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stent deployment systems require cumbersome manual retraction of sheaths over the entire length of stents, often necessitating two hands or repeated motions, especially for long stents, which complicates the deployment process.
Innovation Solution
A method involving a slider coupled to the sheath, connected to an engagement plate, which is disengaged from a housing to allow a spring to automatically retract the sheath for complete stent deployment, enabling single-handed operation and simplifying the deployment of long stents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If manual retraction of sheath is used to deploy stent, then deployment control is maintained, but operation becomes cumbersome requiring two hands or repeated motions for long stents
Solution Approach 1:
The spring mechanism automatically retracts the sheath without requiring continuous manual operation. Once initiated, the system self-propels the sheath retraction process, eliminating the need for repeated manual motions or two-handed operation that plagued previous manual systems.
Solution Approach 2:
The deployment process is divided into two distinct phases: initial manual retraction to initiate deployment, followed by automatic spring-driven retraction to complete the process. This periodic action separates the control phase from the execution phase, improving ease of operation.
2Ease of operation
If automatic spring retraction is used for complete deployment, then operation is simplified to single-handed, but initial control and positioning becomes difficult
Solution Approach 1:
The physician performs preliminary manual retraction to position the stent at the desired location before the automatic spring mechanism takes over. This preliminary action ensures accurate positioning and secure engagement within the parent vessel before automatic deployment begins.
Solution Approach 2:
The deployment process is segmented into two distinct stages: manual initiation phase for positioning and control, followed by automatic spring-driven phase for completion. This segmentation allows each phase to optimize for its specific function, maintaining reliability while improving ease of operation.
3Productivity
If sheath retraction is performed over entire length of long stent, then complete deployment is achieved, but deployment time and physician effort increase significantly
Solution Approach 1:
The spring mechanism replaces the physician's manual mechanical retraction effort with elastic potential energy conversion. This substitution dramatically reduces the time and effort required to retract the sheath over the entire length of long stents, improving deployment efficiency.
Solution Approach 2:
The deployment process uses periodic action with initial manual retraction followed by automatic spring-driven retraction. This approach completes the entire sheath retraction process much faster than continuous manual operation, significantly reducing deployment time for long stents.
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
This method allows for controlled initial deployment of stents with manual effort, followed by automatic completion using a spring, simplifying the process and reducing the effort required for deploying long stents, making it more efficient and user-friendly.
Implementation Method 1
a source of stored energy coupled to the engagement plate
Data Source
AI summary
The initial deployment of a self-expanding stent is performed by the physician manually retracting the sheath of a delivery system. This provides the physician with complete control of the initial deployment of the stent. Further, once the stent is securely engaged within the parent vessel, the remaining deployment over the remaining length of the stent is performed automatically by retraction of the sheath by a spring. Since the physician simply initiates the deployment of the stent, the deployment is readily performed using only a single hand of the physician.