Steerable Catheter Axial Member Structure for Lateral Deflection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional steerable catheters face challenges such as undesired lateral deflection and limited bendability, leading to inaccurate positioning within bodily cavities, and require solutions that do not increase catheter dimensions or pose safety risks.
Innovation Solution
A steerable catheter design with an elongate shaft member featuring a cross-section with distinct edge portions of varying radii of curvature and symmetrical configurations to resist lateral deflection, allowing precise steering and positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If high forces are applied by axial steering members to deflect the catheter, then the catheter can be steered to desired positions, but the steerable portion deflects laterally from the pre-determined plane causing inaccurate positioning
Solution Approach 1:
The axial member is designed with an asymmetric cross-section where one edge portion has a larger radius of curvature than the other edge portion. This asymmetric geometry creates differential stiffness along the cross-section, allowing the catheter to resist lateral deflection forces while maintaining controlled deflection in the desired steering plane, thereby improving positioning accuracy during steering operations
2Ease of operation
If compressive loading is provided by axial steering members to deflect the catheter, then the catheter can change direction, but the elongate catheter shortens providing false indication of distal end position
Solution Approach 1:
The asymmetric cross-section of the axial member with different radii of curvature on opposite edges creates a structural configuration that resists compressive loading-induced shortening. The differential geometry allows the catheter to maintain its longitudinal length while still achieving directional deflection through the steering members, ensuring accurate position indication during steering
3Adaptability or versatility
If the catheter is designed to allow greater deflection amounts, then the catheter can reach difficult positions within bodily cavities, but the catheter dimensions increase hindering percutaneous delivery
Solution Approach 1:
The asymmetric cross-section design optimizes the structural efficiency of the axial member, allowing the catheter to achieve greater deflection ranges without proportionally increasing overall dimensions. The differential radius of curvature configuration enables enhanced bending capability while maintaining a compact profile suitable for percutaneous delivery through restrictive access sites
Data Source
AI summary
Steerable catheters are provided, some of which include an axial member incorporated in an elongate shaft member, where, in some instances, different edge portions of the axial member exhibit different radii of curvature. In some instances, a furthest-apart pair of points on an external boundary of a cross-section of the axial member is closer to an interior edge than an exterior edge of a tubular member of the elongate shaft member.