It was reported that the patient wanted to get her vns removed.She stated that she doesn¿t think it¿s working anymore.She says it worked and helped her in the beginning, but stopped working for her later on and has been that way for a while.Information was received that the patient¿s device was fully explanted.The explanted generator and lead were received for analysis.Product analysis for the generator was completed and approved.During the analysis, there was no indication from the device that an end of service condition existed.The device output signal was monitored for more than 24-hrs, while the generator was placed in a simulated body temperature environment.Results showed no signs of variation in the pulse generator¿s output signal and demonstrated that the device provided the expected level of output current for the entire monitoring period.The pulse generator diagnostics were as expected for the programmed parameters.The device performed according to functional specifications.Product analysis on the lead was completed and approved.During the visual analysis of the returned 42mm portion quadfilar coil 1 appeared to be broken approximately 9mm from the end of the cut outer / inner silicone tubes.Scanning electron microscopy was performed and identified the area as having extensive pitting which prevented identification of the coil fracture type.The area on the remaining broken coil strands was identified as having extensive pitting which prevented identification of the coil fracture type.Pitting and residual material was observed on the coil surface.It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting.Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution.The abraded opening found on the outer silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids inside the outer silicone tubing.No other obvious anomalies were noted.Based on the findings in the product analysis lab, there is evidence to suggest a discontinuity with the returned portions of the device.Note that since the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.No additional information has been received to date.
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