Medical Guide Wire Tapered Helical Coil Steerability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Medical guide wires face challenges in navigating blood vessels with constrictions and calcified lesions due to issues with steerability, penetrability, and buckling, particularly when encountering hard tissues and plaque, as existing designs either lack sufficient flexibility or rigidity, leading to failure in reaching the true lumen.
Innovation Solution
A medical guide wire with a flexible core and a helical coil structure, featuring a tapered shape, a diameter decreasing coil portion, and a middle connector, where the helical coil has a tightly wound design with a specific diameter ratio and length ratio, providing enhanced steerability and penetrability by maintaining a high spring constant and reducing torsion angle, and optionally coated with a lubricant for improved navigation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the rigidity of the guide wire tip is increased to improve penetrability, then penetration capability is improved, but steerability deteriorates due to reduced flexibility
Solution Approach 1:
The guide wire employs different structural characteristics at different locations: the tip portion has a helical coil structure with high rigidity for penetration, while the proximal portion has a core structure with high flexibility for steering. This local differentiation allows each region to optimize its function independently, resolving the contradiction between penetrability and steerability.
Solution Approach 2:
The guide wire is divided into distinct functional segments: a flexible core portion for steering and a rigid helical coil tip portion for penetration. The middle connector region transitions between these segments. This segmentation allows the wire to exhibit both high flexibility in the proximal region and high rigidity in the distal region, simultaneously achieving steerability and penetrability.
2Ease of operation
If the guide wire tip is made more flexible to improve steerability, then steerability is improved, but penetrability deteriorates
Solution Approach 1:
The guide wire employs different structural characteristics at different locations: the tip portion has a helical coil structure with high rigidity for penetration, while the proximal portion has a core structure with high flexibility for steering. This local differentiation allows each region to optimize its function independently, resolving the contradiction between penetrability and steerability.
3Ease of operation
If the guide wire uses a helical coil structure to improve flexibility, then flexibility is improved, but penetration force is reduced
Solution Approach 1:
The guide wire employs different structural characteristics at different locations: the tip portion has a helical coil structure with high rigidity for penetration, while the proximal portion has a core structure with high flexibility for steering. This local differentiation allows each region to optimize its function independently, resolving the contradiction between penetrability and steerability.
4Strength
If the guide wire tip has high rigidity to penetrate hard tissue, then penetration capability is improved, but the guide wire buckles when encountering resistance
Solution Approach 1:
The guide wire is divided into distinct functional segments: a flexible core portion for steering and a rigid helical coil tip portion for penetration. The middle connector region transitions between these segments. This segmentation allows the wire to exhibit both high flexibility in the proximal region and high rigidity in the distal region, simultaneously achieving steerability and penetrability.
Solution Approach 2:
The guide wire combines different material properties in a composite structure: a flexible core material (such as nitinol or stainless steel wire) combined with a rigid helical coil structure (such as tungsten or gold). This composite construction provides both flexibility for navigation and rigidity for penetration, preventing buckling while maintaining steerability.
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 guide wire achieves high rotational force transmission and penetration capability, effectively navigating through constrictions and calcified lesions with reduced buckling and entanglement, ensuring efficient access to the true lumen while maintaining structural integrity.
Implementation Method 1
A helical coil (13) is attached to the core elongated component (12)... The helical coil includes an equiradial coil portion (13a)... A diameter decreasing coil portion (13b) has the coil distal end, is disposed to extend forwards from the equiradial coil portion (13a)
Implementation Method 2
A diameter decreasing coil portion (13b) has the coil distal end, is disposed to extend forwards from the equiradial coil portion (13a), has a decreasing diameter, and has a length equal to or more than 25 mm
Data Source
AI summary
A medical guide wire includes a flexible long core. A core elongated component is disposed to extend forwards from the core, and has a tapered shape. A helical coil is disposed about the core elongated component, secured by attachment of a coil distal end and a coil proximal end to the core elongated component. The helical coil includes an equiradial coil portion having the coil proximal end, disposed at a portion of the core elongated component on a side of the core. A diameter decreasing coil portion has the coil distal end, extends forwards from the equiradial coil portion, has a decreasing diameter, and has a length 25 mm or more. A diameter ratio D1/D2 of the diameter decreasing coil portion is 1.22-2.31, where D1 is a proximal end diameter of the diameter decreasing coil portion, and D2 is a distal end diameter of the diameter decreasing coil portion.