Guide Wire Inclined Coil Structure for Vascular Selectivity

Solution Overview

Problem

Existing guide wires face issues with selectivity in navigating bifurcation regions, discriminability in distinguishing between healthy and lesioned regions, and prevention of falling off from bent regions within blood vessels.

Innovation Solution

A guide wire design featuring a core shaft with a coil body that includes inclined and flat portions, where the wire is wound obliquely in the inclined portions to enhance frictional resistance and selectivity, and flat portions to facilitate passage through constricted areas, with elliptical cross-sections to prevent damage to vessel walls.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the guide wire is made with a conventional coil body structure, then the guide wire can pass through blood vessels, but the guide wire slips on the inner wall of blood vessels at bifurcation regions, resulting in insufficient selectivity

Engineering Contradiction:

ImproveselectivityVSAvoidslipping on inner wall

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The coil body is divided into different regions with distinct wire cross-sectional shapes: an inclined portion with non-circular cross-section for enhanced selectivity at bifurcation regions, and a flat portion with elliptical cross-section for passage through constricted regions. This local differentiation allows each region to perform its specific function optimally.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The wire cross-sectional shape is changed from a symmetric circular shape to asymmetric non-circular shapes (inclined and flat portions). The inclined portion has a specific orientation angle that creates asymmetric contact with the vessel wall, improving selectivity by preventing slippage in the radial direction while allowing controlled movement.

Inventive Principle:

Principle #4Asymmetry

2Productivity

If the guide wire is pushed through a thrombosis in an atheroma state, then the guide wire can advance with relatively small resistance, but it becomes difficult to determine whether the guide wire has reached the lesioned region

Engineering Contradiction:

Improvepassage through lesioned regionVSAvoiddiscriminability

Core Design Contradiction:

ProductivityVSLoss of information

Solution Approach 1:

The guide wire incorporates a radiopaque member that is visible on X-ray images. This allows the operator to visually detect the position of the guide wire and determine whether it has reached the lesioned region, providing critical visual feedback that was previously unavailable when resistance was low.

Inventive Principle:

Principle #32Color changes

3Adaptability or versatility

If the guide wire enters a bent region of a blood vessel, then the guide wire can navigate the curve, but the guide wire falls off from the bent region due to elastic restoration

Engineering Contradiction:

Improveentry into bent regionVSAvoidfalling off from bent region

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The coil body is divided into different regions with distinct wire cross-sectional shapes: an inclined portion with non-circular cross-section for enhanced selectivity at bifurcation regions, and a flat portion with elliptical cross-section for passage through constricted regions. This local differentiation allows each region to perform its specific function optimally.

Inventive Principle:

Principle #3Local quality

4Reliability

If the wire is wound obliquely in inclined portions to enhance frictional resistance, then selectivity is improved, but the guide wire may cause damage to vessel walls

Engineering Contradiction:

ImproveselectivityVSAvoidvessel wall damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The coil body is divided into different regions with distinct wire cross-sectional shapes: an inclined portion with non-circular cross-section for enhanced selectivity at bifurcation regions, and a flat portion with elliptical cross-section for passage through constricted regions. This local differentiation allows each region to perform its specific function optimally.

Inventive Principle:

Principle #3Local quality

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

Improves selectivity and discriminability in navigating complex vascular structures, reduces the risk of the guide wire falling off from bent regions, and minimizes vessel damage while providing differential resistance for forward and backward motion.

Implementation Method 1

the coil body includes an inclined portion where an angle formed by a long axis of the wire and an axial line of the coil body is acute with respect to a first direction along the axial line of the coil body

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentEP3815733B1Guide wire

Publication Date: 2025.08.06 ASAHI INTECC CO LTD

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AI summary

A guide wire includes a core shaft and a coil body formed by winding a wire around the core shaft. The wire includes a long axis and a short axis in a transverse section. The coil body includes an inclined portion where an angle formed by the long axis of the wire and an axial line of the coil body is acute with respect to a first direction along the axial line of the coil body.