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This report is being submitted as follow up no.1 to provide the device return date in section d9, update section h3, and to provide the completed investigation results.Visual and microscopic inspections: the actual device upon receipt was only a runthrough ns.The platinum coil section and niti-core wire had been fractured.The platinum coil section had been elongated (the coil pitch had been opened).The niti-core wire had been exposed approximately 26mm from the fractured section.No anomaly was found in other sections.Electron microscopic inspection of the fractured section: dimple patterns were found on the top surface at the fractured section.The side surface at the fractured section had been tapered.It was inferred that since pulling force was applied, it was fractured.Confirmation of dimensions: the platinum coil section had been severely damaged and could not be measured.Dimensions of the stainless-steel coil section and the shaft met the factory's specifications.No anomaly was found.Confirmation of the missing length: length of the niti-core wire from the fractured section of main body to the joint of the stainless- steel coil and platinum coil, and niti-core wire: approximately.26mm.Since the length of platinum coil section is 30mm, it was inferred that the missing length was approximately 4mm.No anomaly was found in the manufacturing record and the shipping inspection record.Past simulation test: the distal end of device was trapped and pulling force was applied.As a result, the niti-core wire was fractured at the platinum coil section.The dimple patterns and the taper were found at the fractured surface.Based on the investigation result, no anomaly was found in the manufacturing record and the shipping inspection record.As a possible cause of this case, it was likely that the distal end of device was trapped for some factor, and pulling force was applied in that state, causing it to fracture.However, since the details of procedure were unknown, it was not possible to clarify the cause of occurrence.Ashitaka factory has been making efforts in maintaining the quality of the product by performing following controls.After the product assembling process, the outer diameter is measured on 100% basis to confirm that there is no anomaly in it.In the shipping inspection, pulling strength is measured on sampling basis for each lot number to confirm that there is no anomaly in it.The instructions for use (ifu) of this product includes the following warning: "if any resistance to the runthrough ns or the dilatation catheter is felt during manipulation or if the shape, behaviour or position of the guide wire's tip seems improper, e.G., in a case where the tip is trapped due to vessel spasm or some other cause or the tip is folded, stop manipulating the guide wire (and the catheter) and determine the cause carefully by fluoroscopy and take suitable remedial actions.Then remove the guide wire slowly, without turning, to exchange it for a new one.Continuing guide wire or catheter manipulation in the said situations may result in damage to the vessel, damage to or separation of the guide wire's tip, and/or damage to the dilatation catheter.".
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