Integrally Formed Tissue-Removing Element with Segmented Cutting Teeth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tissue-removing catheters face challenges in effectively cutting and removing plaque tissue from blood vessel walls, particularly in chronic total occlusion and stenoses, due to limitations in cutting efficiency and tissue engagement mechanisms.
Innovation Solution
A tissue-removing catheter with an integrally formed, one-piece tissue-removing element featuring alternating primary and secondary cutting components, including cutting teeth and inner shearing members, designed to rotate and advance through the body lumen, effectively cutting and shearing tissue through a combination of cutting teeth with positive rake angles and inner shearing members that impact tissue radially inwardly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional cutting catheters are used, then the device structure is simple, but the cutting efficiency and tissue removal capability are insufficient
Solution Approach 1:
The tissue-removing element is divided into multiple discrete cutting teeth and shearing members arranged around the circumference. Each cutting tooth functions as an independent cutting unit, allowing simultaneous engagement with tissue at multiple points, thereby significantly increasing cutting efficiency while maintaining a relatively simple overall structure
Solution Approach 2:
The invention combines two distinct tissue-removal mechanisms (cutting teeth for initial engagement and shearing members for radial shearing) into a single integrated tissue-removing element. This merging of functions enables both cutting and shearing actions to occur simultaneously during rotation, improving productivity without requiring separate devices
2Productivity
If cutting teeth with positive rake angles are used, then the cutting efficiency is improved, but the device complexity increases due to integral formation requirements
Solution Approach 1:
Multiple functional components (cutting teeth with positive rake angles, shearing members, and support structures) are merged into a single integrally formed tissue-removing element. This eliminates the need for assembly of multiple parts, simplifying manufacturing while enabling complex cutting geometries that improve cutting efficiency
Solution Approach 2:
The cutting teeth are designed with specific positive rake angle parameters that optimize cutting efficiency. By carefully controlling geometric parameters during integral formation, the design achieves superior cutting performance while maintaining manufacturability through single-piece construction
3Reliability
If multiple primary and secondary tissue-removing components are used, then the tissue engagement is enhanced, but the device complexity increases
Solution Approach 1:
The tissue-removing element is segmented into multiple cutting teeth and shearing members distributed around the circumference, with primary components spaced at specific intervals and secondary components positioned between them. This segmentation provides multiple simultaneous tissue engagement points, enhancing reliability through redundant contact points while maintaining a simple single-piece structure
Solution Approach 2:
Different regions of the tissue-removing element have specialized local functions: primary cutting teeth for main tissue engagement, secondary cutting teeth for additional cutting capacity, and shearing members for radial shearing. This local differentiation of component qualities enhances overall tissue engagement reliability without requiring a large number of identical components
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 catheter achieves efficient removal of both hard and soft tissue by engaging tissue in multiple ways, enhancing cutting efficiency and reducing tissue removal challenges, such as plaque from blood vessel walls, while maintaining structural robustness and minimizing tissue disengagement.
Implementation Method 1
the cutting teeth cut into and/or through tissue in the lumen
Implementation Method 2
Some tissue rides along a radially inner surface of the cutting teeth as the tissue rotates and is sheared radially inwardly by the inner shearing member
Data Source
AI summary
A tissue-removing catheter includes a tissue-removing element operably connected to a drive shaft for rotation of the tissue-removing element about an axis of rotation in a cutting direction. The tissue-removing element is an integrally formed, one-piece body and has an annular tissue-removing head at the distal end of a tissue-removing element body. In some embodiments, primary tissue-removing components include an integrally formed cutting tooth and inner shearing member and are spaced angularly around the tissue-removing blade. Secondary tissue-removing components include cutting teeth and are interposed between the primary tissue-removing components around the tissue-removing blade. The tissue-removing element is made by removing material from a blank to form the primary and secondary tissue-removing components.