N+ Ultra™ Neuro Micro-Guidewire (Chikai Series): Advanced Multi-Layer Coil System for Superselective Navigation

Structural Engineering & Material Innovation

1. Multi-Layer Coil Architecture

• Outer Platinum-Nickel Alloy Coil: Premium 90% platinum / 10% nickel composition providing exceptional radiopacity (density: 20.5 g/cm³) while maintaining optimal flexibility for cerebral vessel navigation.

• Intermediate Stainless Steel Reinforcement Layer: SUS304 stainless steel coil designed for structural integrity and torque transmission enhancement.

• Inner Core Coil System: Precision-wound stainless steel inner coil creating a low-friction lumen for optimal guidewire control and kink resistance.

2. Enhanced Radiopacity Configuration

• Extended Tip Visualization: 5 cm platinum-nickel distal segment ensures continuous high-visibility under fluoroscopy during critical navigation phases.

• Tri-Material Radiopaque System: Strategic integration of platinum-nickel, stainless steel, and tungsten markers creates a graduated visibility profile for precise depth perception.

3. Advanced Hydrophilic Coating Technology

• Extended Coating Coverage: 170 cm hydrophilic polymer coating (activated upon saline contact) provides consistent low-friction performance throughout the working length.

• Multi-Stage Coating Process:

• Base layer: Polyurethane primer for enhanced adhesion

• Intermediate layer: Covalently-bonded hydrogel matrix

• Surface layer: Ultra-smooth cross-linked polymer interface

• Performance Characteristics: Coefficient of friction <0.03 when hydrated; maintains lubricity through >15 passes in simulated tortuous anatomy.

Performance Characteristics

Mechanical Properties

• Torque Response: 1:1 transmission accuracy up to 270° rotation

• Tip Load Options: 1.5g (ultra-soft), 3.0g (standard), 4.5g (enhanced) configurations

• Column Strength: 180 gf buckling resistance

• Recovery Time: Returns to straight configuration within 0.3 seconds at 90° deflection

Navigation Performance

• Trackability: Successfully navigates 360° loops with 1.5 mm radius

• Crossing Capability: 0.012" (0.30 mm) distal profile for superselective access

• Visualization: Continuous 5 cm radiopaque segment with three discrete marker bands

• Friction Reduction: >80% reduction compared to uncoated guidewires

Clinical Application Advantages

Neurovascular Procedures

• Aneurysm Coiling: Enhanced visibility during microcatheter positioning

• Mechanical Thrombectomy: Optimal trackability through tortuous cervical anatomy

• AVM Embolization: Precise superselective catheterization capability

• Flow Diverter Placement: Stable platform for device delivery systems

Peripheral & Specialty Applications

• Retinal Artery Cannulation: Ultra-fine tip control for ophthalmic interventions

• Spinal Interventions: Extended coating for prolonged navigation in spinal vasculature

• Pediatric Neurovascular: Reduced profile with maintained visibility for pediatric anatomy

Quality & Safety Features

Manufacturing Excellence

• Laser-Welded Junctions: Precision welding between coil segments ensures fracture resistance

• Automated Coating Application: Computer-controlled dip coating for uniform thickness

• 100% Visual Inspection: High-magnification quality control of all critical components

Biocompatibility & Safety

• Material Certification: ISO 10993 biocompatibility testing completed

• Latex-Free Construction: Eliminates risk of latex allergy reactions

• MRI Compatibility: Non-ferromagnetic materials suitable for 1.5T and 3T MRI environments

• Sterilization: Ethylene oxide sterilization with <5 ppm residual levels