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Visual inspection of the actual sample: length of the fragment: approximately 54 mm.Length of the main body: approximately 2542 mm.Total length: approximately 2596 mm the total length of the actual sample was confirmed to be within our control standards.Magnifying inspection of the actual sample: [main body] the fractured end of outer layer seemed like it had been torn off.The core wire was protruding from the outer layer in the vicinity of the fractured end.No anomaly such as a scratch was found in other sections.[fragment] the vicinity of the fractured end had been curved and wrinkled.The core wire was exposed at the fractured section.The fractured end of outer layer seemed like it had been torn off.Electron microscopic inspection of the actual sample: the edge of fractured outer layer of the main body had been ripped.The outer layer of the main body was wrinkled the winkles seemed to have been caused when this part was stretched.The fractured end of the fragment had been scratched.From this, it was inferred that some hard object came into contact with the ripped and scratched parts of the actual sample.Dimensions: outer diameter (undamaged hydrophilic-coated section and undamaged ptfe-coated section): within our control standards.There were no abnormalities.The outer layer of actual sample was removed, and electron microscopic inspection of core wire was performed for the state of the fractured section.No tapering was observed in any of the core wires.Dimple pattern was observed on the core wire fracture surface of both portions.Simulation test: we have been aware that the guidewire may be fractured when the following force a) - d) is applied.Furthermore, regarding the core wire, we have also been aware that the characteristics of shape of the side surface of the fractured part and the fracture surface differs as follows depending on the mechanism leading to the fracture.A) when repeated bending force (repeated 90° bending force) is applied.No taper is found on the side surface of fractured section, and dimple patterns (hole-shaped patterns) is generated on the fracture surface.This state was considered to be similar to that of the actual sample.B) when tensile force is applied to a looped guidewire.The side surface of fractured section on the wire is curved and tapered, and the fracture surface is roughened.C) when continuous torque force is applied in the same direction to a curved guidewire.No taper is found on the side surface of fractured section, and radial patterns are generated on the fracture surface.D) when pulling force is applied.The fractured part is tapered.Based on the investigation result, no anomaly was found in the manufacturing record, the shipping inspection record, and dimensions of the actual sample.In this case, as one of the possibilities, it was inferred that the core wire was exposed to an excessive bending load repeatedly and fractured due to metal fatigue, and subsequently, a tensile load was applied to the actual sample while its part near the fracture of core wire was trapped by some kind of hard object, which resulted in the outer layer at the involved site having stretched and fractured.The total length of the actual sample was confirmed to be within our control standards, and it was likely that there was no portion missing from the actual sample.Ashitaka factory has been making efforts in maintaining the quality of this product by performing following work and inspections.The outer diameter of this product is controlled.Before the packaging process, 100% visual inspection is performed.Instructions for use (ifu) of this product indicates as follows: "if any resistance is felt or if the tip's behavior and/or location seems improper, stop manipulating the glidewire advantage and/or the catheter and determine the cause by fluoroscopy.Continuing to manipulate or rotate the glidewire advantage or failure to exercise proper caution may result in bending, kinking, separation of the guide wire's tip, damage to the catheter, or damage to the vessel.".
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