Tissue-removing Catheter Head with Adjustable Cross-section
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Tissue-removing catheters with smaller diameters than occlusive tissue may fail to maintain contact with the lumen wall, reducing their efficacy in restoring patency to body lumens.
Innovation Solution
A tissue-removing catheter with a rotatable tissue-removing head that is adjustable from an initial to an expanded cross-sectional dimension, utilizing an elastically deformable member and expansion mechanisms such as a balloon, elastomer, or movable tube to increase the head's circumference, ensuring consistent contact with the lumen wall.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the tissue-removing element has a smaller diameter than the occlusive tissue, then the catheter can be advanced more easily through the body lumen, but the tissue-removing element cannot maintain contact with the occlusion or lumen wall, reducing efficacy
Solution Approach 1:
The catheter employs a dynamically adjustable tissue-removing head that can change its cross-sectional dimension from a compressed state during advancement to an expanded state during tissue removal. This dynamic transformation allows the head to transition from a smaller profile for easy navigation to a larger profile for effective contact and tissue removal, resolving the contradiction between ease of advancement and contact maintenance.
Solution Approach 2:
The invention changes the physical parameter of the tissue-removing head's cross-sectional dimension by applying radial expansion force through an elastically deformable member. This parameter change enables the head to expand beyond the diameter of the occlusive tissue, ensuring continuous contact and effective tissue removal while maintaining the ability to be compressed for initial advancement.
2Reliability
If the tissue-removing head is expanded to maintain contact with the lumen wall, then tissue removal efficacy is improved, but the device complexity increases due to additional expansion mechanisms
Solution Approach 1:
The elastically deformable member functions as a self-service mechanism that automatically expands the tissue-removing head when subjected to radial compression forces. The elastic properties of the deformable member create a self-regulating system where the expansion and compression occur naturally in response to applied forces, eliminating the need for complex external actuation systems while maintaining effective tissue removal capability.
Solution Approach 2:
The invention utilizes an elastically deformable member that acts as a flexible structure to achieve head expansion. This flexible component allows the rigid tissue-removing head to dynamically change its cross-sectional dimension through elastic deformation, providing a simple yet effective mechanism that avoids complex mechanical expansion systems while ensuring reliable contact with the lumen wall.
3Adaptability or versatility
If multiple head sizes are used to treat different lumen diameters, then treatment versatility is improved, but the cost and device complexity increase
Solution Approach 1:
The tissue-removing head is designed with universal adaptability through its ability to dynamically adjust its cross-sectional dimension. A single head design can treat lumens of varying diameters by expanding to match the specific lumen size, eliminating the need for multiple specialized heads. This multi-functional capability provides treatment versatility while reducing device complexity and cost.
Solution Approach 2:
The dynamic dimension-adjustment capability of the tissue-removing head allows one head to perform the function of multiple fixed-size heads. By changing its cross-sectional dimension in response to the specific lumen diameter, the head adapts to different treatment scenarios, providing versatility without requiring a collection of different head sizes.
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 adjustable cross-sectional dimension of the tissue-removing head ensures effective contact and removal of occlusive tissue, enhancing the catheter's ability to restore lumen patency without relying on high-speed motors or multiple head sizes, thereby reducing costs and improving treatment versatility.
Implementation Method 1
an elastically deformable member disposed inside the tissue-removing head, wherein the elastically deformable member is selectively elastically compressible to increase a cross-sectional dimension of the elastically deformable member from an initial cross-sectional dimension to an expanded cross-sectional dimension larger than the initial cross-sectional dimension
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A tissue-removing catheter includes a drive shaft (12) and a tissue- removing head (14). The tissue-removing head is at the distal end of the drive shaft and is configured to rotate about a longitudinal axis of the drive shaft. The tissue-removing head is selectively adjustable from an initial cross-sectional dimension (D1) to an expanded cross- sectional dimension larger than the initial cross-sectional dimension.