Dual-Coil Guide Wire Structure to Limit Distal Bending Spread
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Solution Overview
Problem
Existing guide wires tend to experience bending at the distal end that spreads to the proximal end when encountering resistance in curved or constricted blood vessels, posing safety concerns.
Innovation Solution
A guide wire design featuring a core shaft with a first coil body surrounded by a second coil body, where the second coil body's bending stiffness is greater than the first, and a tubular body with fixed portions to prevent bending spread, enhancing safety and torquability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a guide wire is advanced through a tortuous catheter path, then the guide wire can reach difficult-to-access positions, but the guide wire may become kinked or buckled and fail to advance further
Solution Approach 1:
The guide wire incorporates a shape memory alloy section that can dynamically change its shape in response to temperature changes. The wire is supplied in a first shape that allows it to navigate tortuous catheter paths, and can be transformed into a second shape with improved pushability and kink resistance by applying heat or mechanical tension, thereby resolving the contradiction between adaptability and advanceability
Solution Approach 2:
The guide wire utilizes temperature-dependent shape memory alloy properties to change its physical parameters. By heating the wire (changing temperature parameter), the alloy transitions from a compliant state suitable for navigation to a stiffer state that resists kinking and improves advanceability through the catheter
2Strength
If the guide wire is made more rigid to resist kinking, then kink resistance improves, but the guide wire becomes harder to navigate through tortuous paths
Solution Approach 1:
The guide wire employs a shape memory alloy section that allows dynamic adjustment of rigidity. The wire can be transformed from a flexible configuration optimized for navigation to a rigid configuration optimized for kink resistance and advanceability, depending on the procedural requirements at different stages
Solution Approach 2:
The guide wire is supplied in a pre-formed first shape that is optimized for navigating tortuous catheter paths. This preliminary configuration allows easy navigation, and can be transformed in situ into a second shape with superior kink resistance when needed
3Ease of operation
If the guide wire has high pushability to advance through the catheter, then advanceability improves, but the guide wire may become more prone to kinking
Solution Approach 1:
The guide wire utilizes a shape memory alloy section that can dynamically adjust its mechanical properties. The wire can be transformed from a flexible navigation-optimized shape to a rigid advanceability-optimized shape with improved pushability and kink resistance simultaneously
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 design prevents bending from spreading to the proximal end, improving safety and usability by allowing controlled bending at the distal end and maintaining flexibility.
Implementation Method 1
The shape memory alloy section is transformable from a first shape to a second shape
Data Source
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AI summary
A guide wire includes a core shaft having an elongated outer shape, a first coil body disposed to surround a distal end portion of the core shaft, a second coil body disposed radially outside from the first coil body, and a distal tip fixing a distal end of the core shaft and a distal end of the first coil body. In the longitudinal direction of the core shaft, a distal end of the second coil body is positioned between the distal end of the first coil body and a proximal end of the first coil body, a proximal end of the second coil body is positioned on the more proximal end side than the proximal end of the first coil body, and bending stiffness of the first coil body is smaller than bending stiffness of the second coil body.