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This report is being supplemented to provide additional information based on the legal manufacturer's final investigation.A review of the device history record found no deviations that could have caused or contributed to the reported issue.Based on the investigation results, a likely mechanism causing the broken cutting wire might be the following: -high frequency current was applied between the cutting wire and the tissue at the point of the contact.As a result, the current density at the contact area increased, and the cutting wire became instantly hot.-high frequency current was applied when the cutting wire and the tissue were being close to each other.As a result, an electrical discharge occurred, and the cutting wire became instantly hot.-high frequency current was applied when the distal end of the device was not protruded enough from the endoscope until the rear end of the cutting wire was in the field of view.The cutting wire and the tissue were being close to each other.As a result, an electrical discharge between the cutting wire and the distal end of the endoscope occurred, and the cutting wire became instantly hot.Since the device was not returned for evaluation, the definitive root cause of the reported issue could not be determined.The following information is stated in the instructions for use: "since the cutting wire is very thin, it may break off in the following cases: the distance between the papilla of vater and the cutting wire is very short, the output is too high or activated while the cutting wire touches metal parts of the endoscope, or the cutting wire is tightened too strong.When the cutting wire breaks off, its proximal end will be retracted toward the endoscope if the slider is pulled.If the slider is pushed, the cutting wire will be pushed out toward the papilla or move sideways.If the cutting wire breaks off, stop the output immediately and pull the slider completely to retract the broken cutting wire into the tube.Then withdraw the sphincterotome from the papilla.Otherwise, patient injury, such as perforations, bleeding, or lacerations within the biliary duct, and/or damage of the endoscope could result.Please follow the instructions below when carrying out sphincterotomy with the guidewire in place.Failure to observe these warnings could lead to injury to the patient, operator, and/or assistant, and may damage the endoscope, instrument, and/or endotherapy accessory.Do not use the guidewire in combination with any high-frequency therapeutic device that is not intended for sphincterotomy.-do not use the guidewire in combination with any high-frequency therapeutic device whose electrode is in direct contact with the guidewire.-set the output mode of the electrosurgical unit to ¿cut¿ or ¿blend¿.-activate the unit after confirming that the cutting wire of the sphincterotome is in contact with the target tissue.-do not use the guidewire if it has excessive bends, broken areas on the guidewire surface, or other damages.-the portion of the guidewire extending from the endoscope¿s biopsy valve should be kept away from the patient, operator, and assistant.-do not withdraw the guidewire during a sphincterotomy.When inserting the instrument into the endoscope, be sure that the cutting wire is parallel to the tube.Otherwise, the metal part of the forceps elevator may contact the cutting wire and peel off the coating material.Do not insert the instrument into the endoscope when the cutting wire is tightened.Doing so may extend the distal end of the insertion portion from the endoscope tip abruptly.This could cause patient injury, such as perforations, bleeding, or mucous membrane damage.It could also damage the endoscope and/or sphincterotome.Do not activate output while tissue is in contact with the torn or damaged coated portion of the distal end.If output is activated while tissue is contacting the torn or damaged coated portion due to insertion into or withdrawal from an endoscope, leakage current, decreased output, and/or thermal injury could result.Do not activate output while the torn or damaged coated portion is in contact with the forceps elevator.Such activation could break the cutting wire at the tear or damage of the coated portion.It may also cause the coated portion to drop into the body.Be sure that the rear end of the cutting wire is extended from the distal end of the endoscope.In case the cutting wire contacts the forceps elevator, insufficient output or unintended tissue injury may occur.When activating output, set the output mode of the electrosurgical unit to ¿cut¿ or ¿blend¿.Activating output in the ¿coagulation¿ mode could break the cutting wire." olympus will continue to monitor field performance for this device.
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