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dennis100
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« on: February 07, 2019, 01:40:18 AM »

Model Number 303-20
Device Problems Corroded ; High impedance; Mechanical Problem
Event Date 05/15/2012
Event Type  Malfunction   
Manufacturer Narrative
 
Event Description
Patient underwent generator and lead explant surgery due to lack of efficacy. The devices were returned for analysis. In the lab, the device output signal was monitored for more than 24-hrs, while the pulse 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. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. There were no performance or any other type of adverse conditions found with the pulse generator. In the lead assembly returned for analysis, an abraded opening was noted on the silicone tubing resulting in portion of the positive coil being exposed. Scanning electron microscopy images of the connector pin and connector ring show that pitting or electro-etching condition have occurred on both the connector pin and connector ring exposed surfaces. An energy dispersive spectrometry analysis was performed on a sample of the deposits observed on the pin. The analysis showed the presence of elements present in stainless steel 316. The higher percentage of iron in this sample suggests oxidation may have occurred. Though it is difficult to state conclusively the observed condition of the connector pin mentioned above may confirm this to be a contributing factor for the reported ¿high impedance¿ allegation. Since the electrode array portion was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead. Other than the above mentioned observations and typical wear and explant related observations, no other anomalies were identified in the returned lead portion. Internal investigation determined that in the event that the lead becomes compromised through wear or trauma (e. G. An abraded opening in the lead¿s silicone tubing), a charge imbalance may form at this location as a result of the alternate current pathway associated with the original model 105 generator design (e. G. Sn<20000). As a result of this charge imbalance and the low pitting potential of quadfilar coil, coil corrosion can occur resulting in a lead discontinuity.

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dennis100
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« Reply #1 on: February 07, 2019, 01:41:26 AM »

Model Number 103
Event Date 07/02/2014
Event Type  Malfunction   
Event Description
Initially, it was reported that high impedance was observed and the patient was experiencing an increase in seizures. It was reported that the patient had recently suffered a fall during ice skating. The physician assistant believes the device was damaged during the fall. X-rays were taken and sent to manufacturer for review. X-rays identified that the lead pin did not appear to be fully inserted into the generator header. The patient underwent surgery. The surgeon opened the chest pocket to check the connection and when the generator was removed the lead pin fell out of the header confirming a generator/lead connection issue. The surgeon implanted a new generator and lead. The explanted lead and generator were received for analysis. Analysis of the lead was completed on (b)(4) 2015. During the visual analysis of the returned 289mm portion what appeared to be rust-like deposits and pitting were observed on the connector pin surface. Scanning electron microscopy was performed and identified evidence of pitting on the surface of the connector pin. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed on the connector pin rust-like deposit and identified the area as consisting of chromium, iron, nickel, silicone and phosphorus. Another eds procedure was performed on the clean surface of the connector pin and identified the area as consisting of chromium, iron, nickel, sodium, manganese, silicone and sulphur. A definite cause for the pitting could not be determined based on the lead portion returned. No other obvious anomalies were noted except for the set of setscrew marks found near the end of the connector pin indicating the lead had not been fully inserted into the cavity of the generator at one time. Additional setscrew marks found on the connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified. Analysis of the generator was completed on (b)(4) 2015. A comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. There were no additional performance or any other type of adverse conditions found with the pulse generator. The generator decoder identified that the high impedance occurred prior to (b)(6) 2014.
 
Manufacturer Narrative
Manufacturer reviewed x-rays of implanted device. X-rays reviewed by the manufacturer, lead pin not fully inserted past the connector block of generator.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=4576543
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dennis100
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« Reply #2 on: February 07, 2019, 01:42:16 AM »

Model Number 302-20
Event Date 12/22/2014
Event Type  Malfunction   
Event Description
X-rays were taken and were reported by the physician to be unremarkable. It was reported that the patient underwent full revision surgery on (b)(6) 2015 to replace the lead. The generator was replaced prophylactically. The explanted devices were returned to the manufacturer. Analysis of the devices is currently underway.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Analysis of the returned lead portions was completed on 02/27/2015 and it identified pitting on the pin surface; reddish deposits on the pin surface were found with a high percentage of iron that suggests that oxidation may have occurred, but the impact of this condition cannot be determined. No other anomalies were identified in the returned lead portion. Note that since the electrode array portion was not returned for analysis, an evaluation cannot be made on that portion of the lead. Analysis of the generator was completed on 03/04/2015 proper functionality of the pulse generator was verified. The device provided the expected level of output current. The battery showed an ifi=no condition. The as-received internal device data showed that the last 25% change in the impedance value was estimated to have occurred during replacement surgery on (b)(6) 2015, where the impedance value changed from high lead impedance to a normal limits range. No adverse conditions were identified for the generator.
 
Manufacturer Narrative
Describe event or problem; corrected data: the previously submitted mdr inadvertently did not include the assessment of the x-rays by the health professional.
 
Event Description
It was reported that device diagnostics resulted in high impedance. It was reported that the patient had recently undergone generator replacement on (b)(6) 2014 for end of service. It was reported that device diagnostics in the operating room were within normal limits (2000 ohms). It was reported that the lead impedance increased gradually following surgery and that on (b)(6) 2014 the high impedance was first observed. It was reported that x-rays were scheduled and surgical revision was planned. No known surgical intervention has been performed to date.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to death. Only a portion of the lead was returned for analysis which did not reveal any lead fractures. A lead fracture is suspected in the lead portion not returned.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=4430709
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dennis100
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« Reply #3 on: February 07, 2019, 01:43:01 AM »

Model Number 300-30
Device Problem Corroded
Event Date 01/01/2018
Event Type  Malfunction   
Manufacturer Narrative
 
Event Description
It was reported that the patient stated that device did not work for him and the patient did want to replace the battery. Follow up with the physician's office revealed that the vns did not change to patient's seizure frequency. The patient did not elect to replace the vns. However, the patient was referred for and underwent full vns replacement surgery due to an end of service condition and the lead compatibility with the new generator. The explanted lead was received by the manufacturer. Lead product analysis is completed. The lead assembly was returned in four portions. What appeared to be rust-like deposits and pitting were observed on the unmarked connector pin surface. Set-screw marks were observed and indicated that proper mechanical contact was present. Scanning electron microscopy, or sem, was performed and identified evidence of pitting and surface irregularities. Continuity checks of the returned lead portions were performed with no discontinuities identified. Based on the findings in the pa lab, there is no evidence to suggest an anomaly with the returned portions of the lead. No additional relevant information has been received to date.
 
https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=7923517
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dennis100
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« Reply #4 on: February 07, 2019, 01:43:51 AM »

Model Number 302-20
Event Date 12/08/2011
Event Type  Malfunction   
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Additional information was received on (b)(4) 2012, when product analysis was completed on the section of the lead assembly that was returned. The lead's electrodes were not returned for evaluation. Scanning electron microscopy images of the pin shows that pitting or electro-etching conditions have occurred on the connector pin at the region where the reddish-brown deposits were noted. An energy dispersive spectrometry analysis performed on a sample of the reddish-brown deposits identified fe, cr, ni, p, mo, na, si, and ca as the composition for the substance. The higher percentage of iron in this sample suggests oxidation may have occurred. Since a portion of the lead, including the electrode array, was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead. Other than the mentioned observations and typical wear and explant related observations, no other anomalies were identified in the returned lead portion. Product analysis on the generator was completed on (b)(4) 2012. In the product analysis lab, 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. Magnet activations performed at the bench (at a distance of one-inch, spacer block, from generator) demonstrate the appropriate magnet output for the programmed settings. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications; there were no performance or any other type of adverse conditions found with the pulse generator.
 
Event Description
Additional information was received on (b)(6) 2012 when the physician reported that no x-rays had been taken by the physician. The patient has been scheduled for a full revision surgery in (b)(6) 2012.
 
Event Description
On (b)(6) 2011 a vns treating physician reported that the vns patient has high impedance. The patient stated that in the past couple of months he has been noticing that when he swipes his magnet he doesn't feel the "tickle" he normally feels. There has been no trauma. The physician has referred the patient for a full revision surgery. The patient's settings were output=2. 5ma/frequency=20hz/pulse width=250usec/on time=30sec/off time=1. 8min/magnet output=2. 75ma/magnet on time=60sec/magnet pulse width=250usec. A battery life calculation was performed which showed 0. 41 years until eri=yes. Although surgery is likely, it has not yet occurred. No further information regarding the high impedance has been received from the physician to date.
 
Manufacturer Narrative
Only a portion of the lead was returned for analysis which did not reveal any anomalies. Device failure is suspected in the lead portion not returned, but did not cause or contribute to a death or serious injury.
 
Event Description
Additional information was received on (b)(6) 2012 when it was discovered that the vns patient had a full revision surgery on (b)(6) 2012. The generator had been replaced for prophylactic reasons and the leads were replaced due to high impedance. The lead impedance after surgery was reported to be within normal limits. The explanted lead and generator were returned to the manufacturer for product analysis on (b)(6) 2012 that has not yet been completed.
 
Event Description
Additional information was received on (b)(6) 2012 when it was discovered that the vns patient was scheduled for surgery on (b)(6) 2011 but it was cancelled because the patient had something to drink. The surgery will be rescheduled. The patient was last seen by the physician on (b)(6) 2011 and this was when the high impedance was first observed. A system diagnostics test showed results of lead impedance=high/near end of service=no. The patient's device was then disabled that day due to the high impedance. Although surgery is likely it has not yet occurred.

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dennis100
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« Reply #5 on: February 07, 2019, 01:44:44 AM »

Model Number 302-20
Event Date 02/12/2014
Event Type  Malfunction   
Event Description
It was reported that the vns patient was experiencing an increase in seizures. The device could not be interrogated so the reported event was suspected to be due to end of service. Additional information was received stating that the patient underwent generator and lead replacement surgery on (b)(6) 2014. Prior to the case, diagnostic results revealed high impedance (dc dc ¿ 7) and end of service. The generator was replaced first and diagnostic results with the existing lead revealed high impedance (impedance value >= 10,000 ohms). The lead was then replaced and diagnostic results revealed lead impedance within normal limits. The surgeon noted that fluid appeared from the explanted lead when it was transected. Additionally, the surgeon stated that one of the wires looked rusted. The explanted generator and lead have not been returned. Review of the available programming and diagnostic history showed normal diagnostic results through (b)(6) 2012.
 
Event Description
Additional information was received stating that the neurologist did not have any issues communicating with other patients¿ devices and that his programming system was functioning normally. The neurologist was unaware of the reported high lead impedance so x-rays were not taken and the patient¿s device was not programmed off. No patient manipulation or trauma was reported. Attempts for product return have been unsuccessful.
 
Manufacturer Narrative
Only a portion of the lead was returned for analysis which did not reveal any anomalies. Device failure is suspected in the lead portion not returned, but did not cause or contribute to a death or serious injury.
 
Manufacturer Narrative
Review of the available programming and diagnostic history. Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
The explanted generator and lead were returned to the manufacturer for analysis. Based on the bench analysis and the electrical test results, the generator exhibited current consumption rates that were within specification; thereby, demonstrating normal battery depletion to an end of service condition. Monitoring of the device output signal showed no signs of variation in the pulse generator¿s output signal and demonstrated that the device provided the expected level of output current. The pulse generator diagnostics were as expected for the programmed parameters. With the exception of the parameters that associated with a low battery condition, the device performed according to functional specifications. Analysis determined normal functionality and normal electrical performance of the pulse generator, which will be used to conclude that no abnormal performance or any other type of adverse condition was found with this device. Analysis of the returned lead portion is currently underway.
 
Event Description
Product analysis was completed on the lead. Note that a large portion of the lead assembly including the electrodes was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. The condition of the returned lead portion is consistent with conditions that typically exist following an explant procedure. No obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portion were performed, during the visual analysis, and no discontinuities were identified. Based on the findings in the product analysis lab, there is no evidence to suggest discontinuities in the returned portion of the device which may have contributed to the stated allegation of high impedance. Note that since a large portion of the lead assembly including the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3677778
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dennis100
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« Reply #6 on: February 07, 2019, 01:45:33 AM »

Model Number 300-20
Event Date 04/08/2014
Event Type  Malfunction   
Manufacturer Narrative
Only a portion of the lead was returned for analysis which did not reveal any anomalies. Device failure is suspected in the lead portion not returned, but did not cause or contribute to a death or serious injury.
 
Event Description
On august 18, 2014 product analysis was completed on the explanted generator. Results of diagnostic testing indicated that the battery status indicated ifi=no in the product analysis lab. The battery voltage was 2. 895 volts (not at ifi) as measured during completion of the final electrical test. Electrical test results showed that the pulse generator performed according to functional specifications. There were no adverse functional, mechanical, or visual issues identified with the returned generator. The review of the device's internal memory showed the impedance went from 9799ohms to 12299ohms on (b)(6) 2014, both of which are high impedance. Product analysis was completed on the lead on 9/2/14. Except for slight observed pitting on the negative connector pin and one abraded outer tubing observation, there were no observed product related issues with the returned lead portions. Scanning electron microscopy images of the unmarked connector pin show that pitting or electro-etching conditions have occurred on the connector pin surface at the areas where reddish-brown deposits were noted. An energy dispersive spectrometry (eds) analysis performed on the sample of the reddish-brown deposits observed on the pin showed the presence of some elements typically observed on stainless steel 316/316l. The higher percentage of iron observed in this sample suggests that an oxidation process may have occurred. The exact impact of this condition on any on the reported "high impedance" allegation is unknown. Note that since a portion of the lead (including the electrode array) was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead. The outer silicone tubing is abraded open and the lead assembly has dried remnants of what appear to have once been body fluids inside the inner and the outer silicone tubing of the second portion of the returned lead. No obvious point of entrance was noted other than the identified tubing openings and the end of the returned lead portion.
 
Event Description
On (b)(6) 2014 it was reported that the generator and lead would be returned for product analysis. A full revision surgery had taken place on (b)(6) 2014 due to the high impedance. The generator and lead were received for product analysis on (b)(4) 2014. Product analysis is still underway and has not yet been completed.
 
Manufacturer Narrative
Device manufacturing records were reviewed. Review of manufacturing records confirmed that the lead passed all functional tests prior to distribution. Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
It was reported that a vns patient received a high impedance warning during diagnostic testing and that the patient¿s generator was disabled as a result. Last successful diagnostic results were reportedly obtained seven (7) months earlier. Surgery has not occurred to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3786843
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dennis100
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« Reply #7 on: February 07, 2019, 01:46:20 AM »

Model Number 302-20
Event Date 12/27/2012
Event Type  Malfunction   
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Reporter indicated that during a prophylactic vns generator replacement surgery, the lead was noted to be broken when the generator was removed from the patient. It is not known if the lead was accidentally cut in the surgery or broke prior to the surgery. Vns diagnostics testing immediately prior to the surgery revealed normal results. A new lead and generator were implanted. The explanted lead and generator have been returned and are pending analysis. Attempts for additional information are in progress.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death or serious injury. Additionally, the failure was due to significant patient manipulation of the lead.
 
Event Description
Analysis of the returned vns generator and lead was completed. The generator performed according to functional specifications. During the product analysis there were no anomalies found with the pulse generator. During the lead visual analysis of the returned 43mm portion what appeared to be rust-like deposits and pitting were observed on the connector pin surface. Scanning electron microscopy was performed and identified evidence of pitting on the surface of the connector pin. Eds (energy dispersion spectroscopy - provides chemical or element identity/composition analysis) was performed on the connector pin rust-like deposit and identified the area as consisting of chromium, iron, nickel and molybdenum. Another eds procedure was performed on the clean surface of the connector pin and identified the area as consisting of chromium, iron, fluorine, nickel and molybdenum. A definite cause for the pitting could not be determined based on the lead portion returned. During the visual analysis of the returned 43mm portion the ends of the quadfilar coils appeared to be twisted together inside the connector boot. Scanning electron microscopy was performed and identified the area as being twisted together and mechanically damaged which prevented identification of the coil fracture type with residual material and no pitting. It is unknown if the breaks occurred while stimulation was present due to the absence of metal pitting on the broken coil wire surfaces. These findings are consistent with patient manipulation/rotation of the device while it was implanted (twiddler). The condition of the remaining portions of the returned lead is consistent with that which typically exists following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified. However, based on the overall condition of the returned lead, there appears to be evidence of significant manipulation, which may have contributed to the observed stress-induced fractures. Note that since a large portion of the lead assembly (body) including the electrodes was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.

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« Reply #8 on: February 07, 2019, 01:47:40 AM »

Model Number 103
Event Date 02/07/2012
Event Type  Malfunction   
Manufacturer Narrative
Manufacturer reviewed x-rays of implanted device. X-rays reviewed by manufacturer, no gross lead discontinuities visualized. A lead pin not being fully inserted into the header of the generator cannot be confirmed. Additionally filter feedthrough wires could not be assessed fully.
 
Event Description
Device history review was performed and all items signed off on prior to distribution.
 
Event Description
The patient had full revision surgery performed on (b)(6) 2013. Their explanted products have not at this time been returned for analysis.
 
Manufacturer Narrative
Device malfunction suspected, but did not cause or contribute to a death.
 
Event Description
Additional information was received that since the patient's vns has been disabled the patient has been having an increase in seizures. The patient will have surgery scheduled to check the lead pin and possibly a full revision. Unknown at this time if the battery will be replaced. At this time no surgery date is set.
 
Event Description
The generator was returned for analysis. Results of diagnostic testing indicated that the battery status indicated ifi=no in the pa lab. The battery voltage was 2. 951 volts, (not at ifi) as measured during completion of test parameter 7. 16. 10. 2 of the final electrical test. The data in the diagaccumconsumed memory locations revealed that 41. 803% of the battery had been consumed. Electrical test results showed that the pulse generator performed according to functional specifications. There were no adverse functional, mechanical, or visual issues identified with the returned generator. An analysis was performed on the returned lead portions. Note that the electrodes were not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis of the returned 88mm portion what appeared to be rust-like deposits and pitting were observed on the connector pin surface. Visual analysis was performed and identified evidence of pitting and deposits on the surface of the connector pin. A definite cause for the pitting could not be determined based on the lead portion returned. The condition of the remaining portions of the returned lead is consistent with that which typically exists following an explant procedure. No other obvious anomalies were noted except for the setscrew marks observed near the end of the connector pin, indicating the connector pin had not been fully inserted into the cavity of the pulse generator at one time. The marks are evidence of a potentially insufficient mechanical contact between conductive surfaces of the generator and connector ring, resulting in a suspect electrical connection to the lead. However, based on the location of the setscrew marks on the pin, it is unknown whether a good electrical connection was present for the connector ring. Continuity checks of the returned lead portions were performed, during the visual analysis, and no discontinuities were identified. Based on the findings in the product analysis lab, there is no evidence to suggest discontinuities in the returned portions of the device. Note that since the electrodes array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.
 
Event Description
An update was received in regards to the patient. Their device has been disabled for about a month, and is going to be left off for now. The family feels the vns may not be beneficial for the patient's seizures; however, their treating physician feels it is beneficial since their medication has been increased since the high impedance/device disablement occurred. Since the family feels it has not been beneficial, they have elected not to have the patient's device replaced at this point. In three months, the patient will have an eeg to evaluate if anything has changed. At that point, it will be decided if a replacement will occur.
 
Event Description
A vns treating physician reported that their was a vns patient showing high lead impedance on his generator. When system diagnostics were performed (high lead impedance >10000 ohms) was noted. The patient's device was disabled at that time and they were referred for x-rays. The physician reviewed the x-rays and didn't notice anything. At this time they have not been sent to the manufacture for review. The patient is a wrestler at school and specifically noted that on (b)(6), he got a really strong jolt twice in the neck while wrestling. The patient now reported that he could no longer feel the stimulation during normal mode and magnet mode, but when did a magnet swipe in the appointment, he had some voice alteration, which is normal for him. The physician initially believed that the patient wasn't getting any efficacy from the therapy since there wasn't a change in the seizures, but since (b)(6), the patient has had an increase in his grand mal and petit mal seizures (baseline above). The parents feel that the patient was receiving efficacy from the therapy. No surgery is planned at this time.
 
Manufacturer Narrative
Suspected medical device: 1, 2, 4 corrected data: updated to generator information. Device manufacture date (mo/day/yr) corrected data to generator information.
 
Event Description
The patient's explanted lead was returned for analysis and is pending completion. It was noted that it was reported that their lead was broken and the patient was having a shock sensation in their neck on the return product form.
 
Manufacturer Narrative
 
Event Description
The site feels the patient not feeling their stimulation is related to their high impedance and seizures are possibly related, but still under investigation at the site. X-rays were received for review. The generator is present in the left chest. The lead wires appear intact at the connector pin. However, the connector pins do not appear to be fully inserted in the x-ray images provided. It appears that one feedthru wire may be bent, but since there is only one angle of the x-rays with the feedthru wires visible, it is unable to be assessed whether the wires are intact. The electrodes appear to be in the correct orientation, but the strain relief is not placed per labeling. A strain relief bend is present, however no strain relief loop is present. The first tie-down is placed lateral to the anchor tether, and the second tie-down is placed lateral to the strain relief bend. However, there is no tie-down securing a strain relief loop. There is a portion of the lead not visible upon the superior portion of the generator, so continuity in that portion of the lead cannot be assessed. There were no acute angles or lead discontinuities seen in the visible portion of the lead body. Based on the x-ray images provided, the cause for the reported high impedance is possibly attributed to the connector pin not being fully inserted into the connector block but unable ot be confirmed as only one view reviewed. In addition, it cannot be assessed whether the feedthru wires are intact. The presence of a microfracture in the lead or a lead discontinuity in the portion of the lead that was behind the generator cannot be ruled out. Surgery has not been scheduled at this time.
 
Manufacturer Narrative
Type of report corrected data; omitted on initial report, 30 day report.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=2527830
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dennis100
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« Reply #9 on: February 07, 2019, 01:48:28 AM »

Model Number MODEL 250
Event Date 03/30/2012
Event Type  Malfunction   
Event Description
It was reported that the physician's vns handheld computer was not able to hold a charge even after being plugged in overnight. Troubleshooting was unable to be performed due to the issue. Information was later received confirming that the handheld computer was non-responsive and no charging indicator lights or activity from the handheld were seen. The faulty handheld was returned and underwent analysis. Analysis confirmed the non-functionality. The printed circuit board appeared to be damaged due to fluid ingress however a hairline crack was also observed in one of the solder connections for the sync connector. Rust was observed on some surfaces inside the handheld computer. The broken solder connection could result in intermittent ability to charge or power the handheld computer. After the solder connection was repaired, the handheld computer remained non-functional due to the fluid damage. Both of the anomalies would result in the scenario as reported by the physician and it cannot be determined when either anomaly began. As a result, it is uncertain if the broken solder connection, the fluid ingress, or both was present at the time of the report by the physician. No adverse events have been reported as a result of the issue.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death or serious injury.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=2551804
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« Reply #10 on: February 07, 2019, 01:49:45 AM »

Model Number 102
Event Date 08/25/2011
Event Type  Injury   
Event Description
On (b)(6) 2012, additional information was received when the surgeon requested a copy of the product analysis results for the generator as he said the generator looked like it "might have leaked".
 
Event Description
On december 6, 2011 additional information was received from the surgeon. The surgeon has no evidence that there was any patient manipulation that could have caused the high impedance or infection. No x-rays were taken. The surgeon stated that cultures were taken during surgery and both aerobic and anaerobic cultures were negative. The surgeon believes that the patient's events are directly related to the vns. He stated that the patient developed an increased seizure frequency in 2009 and a decision was made to replace the vns generator. When the new generator was turned on, the patient experienced significant pain and has had vocal cord paralysis since that point in time, approximately (b)(6) 2009. The lead was then replaced. The patient's vocal cord paralysis had not recovered by (b)(6) 2010 and she underwent operative nerve transposition to help with the vocal weakness. The patient was seen in (b)(6) 2011 with pain at the generator site. The patient had stated that she had been experiencing pain for several months prior and the surgeon stated that there was necrotic-appearing tissue at the incision site itself. The surgeon said he was concerned that there was a possible infection, but there was not purulent material at the time of surgery. The surgeon instead said there was very unusual appearing changes to the tissue surrounding the device, and the device itself had a hard metallic build up around it. The surgeon stated that therefore, the device was removed to prevent further injury. The surgeon did not say whether he was aware that the patient had high impedance since (b)(6) 2010 and whether or not the patient's device had been disabled.
 
Event Description
On (b)(6) 2011, a vns implanting neurosurgeon reported that the after the patient's generator was replaced in (b)(6) 2009, the patient was experiencing vocal cord paralysis where her left vocal cord did not move and had to have a re-innervation procedure. The patient was seen again as she developed what looked like a burn or fungating mass over the generator site. The surgeon removed the generator on (b)(6) 2011 and he reported that it had appeared to have leaked into the pocket; there was metal and scar tissue on histology and the device looked like a rusted battery. Clinic notes from the surgeon were also received. The notes dated (b)(6) 2011 revealed that the patient was experiencing worsening pain at the generator pocket site and had gone to the hospital and been evaluated for any cardiac disease. No cardiac disease was found. She started using a heating pad over the device and she reported that she developed significant blistering at the incision site of the generator and that this has been slowly improving. The device has become more prominent and more painful over the last few weeks however. The surgeon reported that the patient's skin is black and convoluted over the patient's generator incision scar. The device is easily palpable and somewhat mobile. He stated that the patient has likely a burn with some necrosis of the skin at the generator site. It also seems that she may be developing an infection at the generator site and that it should be removed. The surgeon said the patient's seizure control is now much worse without the vns functioning. The operative report from the date of explant, (b)(6) 2011, was also received by the surgeon. The report reveals that the patient had an existing 5cm linear skin incision from the implant of the generator and that a central area of this had turned black and widened to about 0. 5 cm in size. Therefore, an incision was performed to ellipse out the prior scar. The subcutaneous fat was found to be relatively normal in appearance; however, a capsule was encountered with significant fluid and samples were taken for cultures. The capsule was relatively black in color and there appeared to be a wall of possible hemosiderin-stained tissue, several millimeters thick, all within the generator pocket. The surgeon reported that the color of the titanium close to the header of the generator was altered and pictures were taken of it. The surgeon also stated that there was also a collection of very hard black porous material intimately attached to the device. The generator was explanted and the skin biopsy was sent for pathological evaluation. The generator pocket was then copiously irrigated and all of the black material within the scar capsule was removed mechanically. The wound was then closed. The patient's programming history was reviewed in the manufacturer's database which revealed that high impedance was detected on (b)(6) 2010 with a system diagnostics test and normal mode diagnostics test showing results of output=limit/lead impedance =high/dcdc=7/eri=no. The patient was disabled that day to output =0ma/frequency=30hz/pulse width=500usec/on time=30sec/off time=3min/magnet output=0ma/magnet pulse width=500usec/magnet on time=60sec. The manufacturer's consultant reported that she obtained the explanted generator from the surgeon on (b)(6) 2011 and will be sending it back to the manufacturer for product analysis. It has not yet been received by the manufacturer to date. When additional information is received, it will be reported.
 
Manufacturer Narrative

Event Description
Additional information was received on (b)(6) 2011 when product analysis was completed on the explanted lead. A large portion of the lead assembly body, including the electrodes, was not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. The connector pin quadfilar coil appeared to be broken approximately 213mm from the end of the connector boot. The area was identified as being thin which prevented identification of the coil fracture type with evidence of electro-etching, pitting and residual material on the surface. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Discoloration was observed inside the majority of the outer silicone tubing. Discoloration was observed throughout the inside of the connector pin inner silicone tubing and on the quadfilar coil. What appeared to be pieces of inner silicone tubing were observed inside the outer silicone tubing. The tubing discoloration suggests that fluid was present in the tubing at some point in time. Based on the returned lead portion, the initial location of fluid ingress into the tubing cannot be determined. With the exception of the identified discontinuity, pitting, and the discoloration observed, the condition of the returned lead portion is consistent with conditions that typically exist following an explant procedure; no other obvious issues were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Additional information has been requested from the surgeon but no further information has been received to date.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death.
 
Event Description
Additional information was received on (b)(6) 2011 when the explanted generator and lead were returned to the manufacturer for product analysis. Product analysis was completed on the generator on (b)(6) 2011. Bodily fluid remnants were observed in the negative connector block and header cavity. The anomalies in the header area may have been a contributing factor to the adverse events. Corrosion/dried fluids and pitting conditions in the negative connector block and setscrew were observed and are most likely related to the observed fluid ingress of the lead that was returned with this pulse generator. The septum was not cored. In the product analysis lab, 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. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. Other than the visual observation of the header area, there were no performance or any other type of adverse conditions found with the pulse generator. Although initial visual analysis of the lead showed fluid ingress, full product analysis on the lead is still pending.
 
Manufacturer Narrative
There were observed corrosion/dried fluids and pitting conditions in the negative connector block and setscrew that were most likely related to the observed fluid ingress of the lead that was returned with this pulse generator. In the product analysis lab, 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. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. Other than the visual observation of the header area, there were no performance or any other type of adverse conditions found with the pulse generator. Product analysis on the lead has not yet been completed.

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dennis100
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« Reply #11 on: March 20, 2019, 10:37:16 AM »

Model Number 304-20
Device Problem Fracture
Event Date 10/14/2015
Event Type  Malfunction   
Event Description
It was reported that the patient had a fractured lead but underwent replacement on (b)(6)2015. It is unknown what specific devices were replaced (generator and/or lead). It is also currently unknown how the lead was determined to be fractured. No additional relevant information has been obtained to date.
 
Event Description
Additional information was received which clarified that both the generator and lead were explanted on (b)(6) 2015. No additional relevant information has been obtained to date.
 
Event Description
The explanted generator and lead were received on 01/29/2016. The reported "fracture of lead" allegation was not verified. Scanning electron microscopy images of the connector pin verified that pitting or electro-etching conditions have occurred on the connector pin. An energy dispersive spectrometry (eds) analysis performed on a sample of the reddish-brown deposits observed on the pin showed the presence of some elements present in stainless steel 316. The higher percentage of iron in this sample suggests oxidation may have occurred. An abraded opening of the outer tubing was observed in one location. Since a portion of the lead (including the electrode array) was not returned for analysis, an evaluation and resulting commentary could not be made on that portion of the lead. Other than the above mentioned observations and typical wear and explant related observations, no other anomalies were identified in the returned lead portions. The reported allegation of "high impedance" was not duplicated in the pa lab. Various electrical loads were attached to the pulse generator and results of diagnostic tests demonstrate that accurate resistance measurements were obtained in all instances. In the pa lab, 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. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. The battery, 3. 036 volts, shows an ifi=no condition. In addition, signs of discoloration were also observed on the pulse generator case, which is consistent with the adhered remnants of dried body fluids following an explant process. No other surface abnormalities (such as sharp edges, header delamination, open pockets, decomposition, corrosion or voids) were noted on this device. Observations under pa lab bench microscope revealed pitting on the negative connector block and setscrew. Other than the noted visual anomalies, there were no performance or any other type of adverse conditions found with the pulse generator.

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dennis100
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« Reply #12 on: April 24, 2019, 01:33:03 AM »

Model Number 304-20
Device Problem High impedance
Event Date 11/22/2016
Event Type  Malfunction   
Event Description
It was reported by a medical professional to a company representative that a vns patient¿s device has high lead impedance. The impedance value was noted to be high. It was provided the patient did not have any side effects as a result. The impedance value at surgery was within normal limits. The patient was referred for lead revision. During surgery, the surgeon opened the pocket and noticed the lead pin was not fully tightened into the generator. The surgeon used fluoroscopy to examine the lead and did not find anything abnormal. The lead impedance was then tested and was within normal limits. The surgeon then properly inserted and tightened down the lead and the lead impedance was within normal limits again. The patient was closed and the generator was turned back on to the most recent settings. Additional relevant information has not been received to-date.
 
Event Description
Follow-up from the company representative provided that the patient¿s device is showing high lead impedance still. It was stated that there has not been any trauma or manipulation. X-rays were reported to have been taken by the physician and they stated there were no apparent issues. It was stated that lead impedance was high, when the patient was sitting down, standing up, and laying down. The patient was referred for revision surgery. No known surgery has occurred to-date.
 
Event Description
Lead revision surgery occurred and the explanted device was received by the manufacturer on (b)(6) 2017. Analysis is underway, but has not been completed to-date.
 
Manufacturer Narrative
(b)(4).
 
Event Description
Analysis was completed on the returned lead portion (b)(6) 2017. The electrodes were not returned for analysis and a complete evaluation could not be performed on the entire lead product. During the visual analysis what appeared to be rust like deposits were observed on the connector pin surface. Scanning electron microscopy was performed and identified evidence of rust like deposits and pitting on the connector pin surface. A definite cause for the pitting could not be determined based on the lead portion returned. The condition of the returned lead portion is consistent with that which typically exists following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portion were performed, and no discontinuities were identified. There is no evidence to suggest discontinuities in the returned portion of the device.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=6191004
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