Tapering Coil Catheter with Varying Durometer Jacket

Solution Overview

Problem

Medical catheters face challenges in navigating through tortuous vasculature due to buckling and kinking, especially when engaging with guidewires, which limits their ability to reach distal tissue sites effectively.

Innovation Solution

A catheter design featuring an outer jacket with varying durometer sections and a structural support member that tapers in diameter, combined with a seamless inner liner, to provide flexibility and structural integrity, resisting geometric deformation when engaged with guidewires and maintaining a large inner lumen for effective aspiration and device delivery.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the catheter uses a uniform rigid structure to resist buckling and maintain shape, then structural integrity is improved, but the catheter cannot navigate tortuous vasculature due to lack of flexibility

Engineering Contradiction:

Improvestructural integrityVSAvoidability to navigate tortuous vasculature

Core Design Contradiction:

StrengthVSAdaptability or versatility

Solution Approach 1:

The catheter is divided into multiple sections with different durometer values along its length. The proximal section has a higher durometer (more rigid) to provide structural integrity and resistance to buckling, while the distal section has a lower durometer (more flexible) to navigate tortuous vasculature. This segmentation allows each section to perform its specialized function independently.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the catheter are assigned different material properties (durometer values) based on their specific functional requirements. The proximal portion near the operator's hand is made stiffer for control and pushability, while the distal portion at the treatment site is made softer for navigation through curved vessels. This local differentiation of material properties resolves the contradiction between overall structural integrity and local flexibility.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If the catheter uses a softer, more flexible structure to navigate tortuous anatomy, then adaptability is improved, but the catheter buckles and kinks when engaging with guidewires

Engineering Contradiction:

Improveability to navigate tortuous vasculatureVSAvoidresistance to buckling and kinking

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The catheter is divided into multiple sections with different durometer values along its length. The proximal section has a higher durometer (more rigid) to provide structural integrity and resistance to buckling, while the distal section has a lower durometer (more flexible) to navigate tortuous vasculature. This segmentation allows each section to perform its specialized function independently.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the catheter are assigned different material properties (durometer values) based on their specific functional requirements. The proximal portion near the operator's hand is made stiffer for control and pushability, while the distal portion at the treatment site is made softer for navigation through curved vessels. This local differentiation of material properties resolves the contradiction between overall structural integrity and local flexibility.

Inventive Principle:

Principle #3Local quality

3Productivity

If the catheter reduces outer diameter to maintain a large inner lumen, then aspiration efficiency is improved, but the catheter becomes more prone to buckling and kinking

Engineering Contradiction:

Improveaspiration efficiencyVSAvoidresistance to buckling and kinking

Core Design Contradiction:

ProductivityVSStrength

Solution Approach 1:

The catheter is divided into multiple sections with different durometer values along its length. The proximal section has a higher durometer (more rigid) to provide structural integrity and resistance to buckling, while the distal section has a lower durometer (more flexible) to navigate tortuous vasculature. This segmentation allows each section to perform its specialized function independently.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the catheter are assigned different material properties (durometer values) based on their specific functional requirements. The proximal portion near the operator's hand is made stiffer for control and pushability, while the distal portion at the treatment site is made softer for navigation through curved vessels. This local differentiation of material properties resolves the contradiction between overall structural integrity and local flexibility.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS11219740B2Catheter including tapering coil member

Publication Date: 2022.01.11 COVIDIEN LP

AI summary

In some examples of a method of forming a catheter, a structural support member is positioned over an inner liner. Prior to being positioned over the inner liner, the structural support member tapers in diameter along at least a portion of a length of the structural support member.