The subject device was not returned to olympus medical systems corp.(omsc) for evaluation.Therefore, the exact cause of the reported event could not be conclusively determined.Since the serial number is unknown, the device history record could not be reviewed.However, omsc has only shipped devices that passed the inspection.In the literature, there is no description of the device's malfunction.
|
Olympus medical systems corp.(omsc) received the following report from the user.During an endoscopic mucosal resection for a 40s woman, the subject device was used.The wire of the subject device broke at the part between the thumb and index finger of the slider after the loop was tied on the base of the stalk-shaped polyp.The user cuts the sheath with pliers due to the loop was not released.After that, the scope was removed, the scope was reinserted, and the mucosal side of the loop was excised with the kd-1u as in the esd procedure to remove the loop (because there was no gap between the coil sheath and the loop stopper).The intended procedure was canceled, the patient was needed unscheduled hospitalization due to massive bleeding of the procedure.
|
The subject device was returned to olympus medical systems corp.(omsc) for evaluation.As it was pointed out, the loop was not detached.The operation pipe and the operating wire were deformed and broken.The tube sheath, the coil sheath and the operating wire were broken near the operating portion.The shape of the broken surface indicates that the area was severed mechanically by using a tool.When the loop was pulled, it came off from the distal end of the coil sheath.A part of the tissue had been tied to the distal end of the loop, and one clip was placed to the tissue.It was confirmed that a part of the loop at the proximal side was being crushed.Investigation was carried out by disassemble the subject device to confirm the shape of the hook.It was confirmed that the distal end of the hook was chipped and broken.The broken portion of the distal end of the hook was not returned for investigation.The manufacturing record was reviewed and found no irregularities.The exact cause of the reported event could not be conclusively determined.Since a part of the loop at the proximal side was being crushed, the following mechanism may cause that the loop tried to be release but the slider was difficult to be operated and the loop was not detached from the hook, then the operating pipe into the handle and the operating wire into it were deformed and broken.The loop was unhooked while the coil sheath was retracted into the tube sheath, or the loop was unhooked while the loop was hooked around the tissue to affix the distal end of the tube sheath.The tube sheath was pulled toward the proximate side while the hook was extended from the distal end of the coil sheath.Since the tube sheath had been pulled to the proximal side, the tube pulled the loop and the loop was retracted into the coil sheath.As a result of the situation stated above, the loop was caught in between the hook and inside of the coil.As a result, the loop stopped moving.The slider was forcefully operated while the loop stopped moving, causing the operation pipe to deform and break.Since a part of the loop at the proximal side was being crushed, the hook might have broken off due to an excessive force applied to the hook, after the loop was not detached from the hook while the loop was caught in between the hook and inside of the coil.However, aomori olympus could not identify how the hook was broken.Due to an emergency situation, the tube sheath and the coil sheath were severed by using a mechanical tool.This caused the tube sheath and the coil sheath to break near the operating portion.The above device handling has warned in the instruction manual.
|