This report is being submitted to provide investigation findings.Device evaluation: two subject devices were returned for investigation.#1 the model number was nm-401l-0425.The lot no.Of subject device was k0514.(manufacturing date:2020/05/14).The needle could extend from the outer tube.It was not possible to inject liquid when the slider was pushed.However, it was possible to inject liquid when the slider was pulled.The outer tube was not buckled.The needle tube presented compressive buckling.No other abnormalities that could lead to the phenomenon of the reported event could not be confirmed.#2 the model number was nm-401l-0425.The lot no.Of subject device was k0514.(manufacturing date:2020/05/14).The needle could extend from the outer tube.It was not possible to inject liquid when the slider was pushed.However, it was possible to inject liquid when the slider was pulled.The outer tube was not buckled.The needle tube presented compressive buckling.No other abnormalities that could lead to the phenomenon of the reported event could not be confirmed.The device history record (dhr) was reviewed for the lot and there was no anomaly with the event-related items.The record includes the following.-process inspection sheet -quality inspection sheet -nonconforming product report.The instruction manual contains the following instructions related to the reported event: ·straighten out the instrument before inspecting it.The instrument can be damaged if it is coiled while the handle is operated.·operate the slider slowly, otherwise the tube could buckle.·do not coil the insertion portion with a diameter of less than 15 cm.This could damage the insertion portion.·when inserting the instrument into the endoscope, retract the needle into the sheath, hold the instrument close to the biopsy valve, and keep it as straight as possible relative to the biopsy valve.Otherwise, the instrument could be damaged.·insert the instrument slowly.Abrupt insertion could damage the endoscope and/or instrument.·stop using the instrument if the insertion portion bends excessively during use.This could result in malfunction, such as failing to extend the needle or inject a fluid.Conclusion summary: it is determined that liquid could not be injected due to compressive buckling of the needle tube.Since friction resistance between the outer tube and needle tube has increased, compressive buckling might have occurred when the needle was extended.A likely mechanism causing friction resistance between outer tube and needle tube might be the following: - the tube was coiled during the inspection for operation - the slider was pushed abruptly.
|