Reported Reactions

Devices › Stimulator, autonomic nerve, implanted for epilepsy

Device brand name · Generator

Pulse Gen Model 103: medical device reports filed with FDA

4,518 reports name it, 2008–2026. Manufacturer given most often on reports: Cyberonics. Product code LYJ.

4,518
device reports naming the brand
0% of all MAUDE reports · about 244 a year
34
reports, 12 months to August 2026
40 in the 12 months before
29.8%
classified as malfunction
58.7% across the product code
8.5%
classified as death, as reported
384 reports · not verified by FDA

4,518 medical device reports received by FDA name the brand "Pulse Gen Model 103" (generator); the manufacturer given most often on reports is Cyberonics; received from January 2008 to July 2026. Brand names are as the reporter or manufacturer wrote them, so one product can appear under several spellings.

34 reports arrived in the 12 months to August 2026, down 15% from 40 in the 12 months before. FDA releases MAUDE data monthly; reports can arrive months after an event, so the newest months grow in later releases. The event types recorded are injury (61.7%), malfunction (29.8%) and death (8.5%); across all stimulator, autonomic nerve, implanted for epilepsy reports (product code LYJ) death is recorded in 5.6% and malfunction in 58.7%. Event type is the reporter's classification of the report, not a verified outcome.

The device problems coded most often are insufficient device problem information (23%), device operates differently than expected (7.4%) and battery problem (6.9%). The patient problems coded most often are seizures, therapeutic response, decreased and death. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."

Reports by month, five years

0815Sep 2021: 6Oct 2021: 10Nov 2021: 10Dec 2021: 72022Jan 2022: 6Feb 2022: 8Mar 2022: 11Apr 2022: 4May 2022: 8Jun 2022: 10Jul 2022: 10Aug 2022: 7Sep 2022: 9Oct 2022: 15Nov 2022: 4Dec 2022: 122023Jan 2023: 6Feb 2023: 4Mar 2023: 7Apr 2023: 3May 2023: 7Jun 2023: 5Jul 2023: 4Aug 2023: 7Sep 2023: 2Oct 2023: 7Nov 2023: 8Dec 2023: 82024Jan 2024: 3Feb 2024: 2Mar 2024: 6Apr 2024: 4May 2024: 1Jun 2024: 2Jul 2024: 2Aug 2024: 1Sep 2024: 6Oct 2024: 6Nov 2024: 7Dec 2024: 22025Jan 2025: 3Feb 2025: 1Mar 2025: 3Apr 2025: 6May 2025: 2Jun 2025: 2Jul 2025: 2Aug 2025: 0Sep 2025: 1Oct 2025: 2Nov 2025: 2Dec 2025: 82026Jan 2026: 10Feb 2026: 0Mar 2026: 0Apr 2026: 2May 2026: 4Jun 2026: 2Jul 2026: 3Aug 2026: 0

Reports by the month FDA received them. FDA releases MAUDE data monthly; reports can arrive months after an event, so the newest months grow in later releases.

By year received

03166312008: 6720082009: 1082010: 20520102011: 3582012: 44820122013: 6312014: 58020142015: 4852016: 35920162017: 2932018: 24120182019: 2192020: 12620202021: 1312022: 10420222023: 682024: 4220242025: 322026: 212026

Event type and report source

Event type, as classified on the report

Death8.5%384
Injury61.7%2,786
Malfunction29.8%1,347
Other0%0
Not given0%1

Who filed the report

Manufacturer report100%4,517
Voluntary report0%0
User facility report0%0
Distributor report0%0
Not given0%1

Grey bar: all 52,004 reports carrying product code LYJ. Event type is the filer's classification and is not verified by FDA.

Device problems coded

Device problem (FDA code)ReportsShareShare across product code
Insufficient device problem information1,03723%9%
Device operates differently than expectedthe device behaved unexpectedly3347.4%4.5%
Battery problema problem with the battery3116.9%3.4%
High impedance2786.2%18.1%
Device displays incorrect message1112.5%2.1%
Failure to interrogate992.2%2.5%
Migration or expulsion of device851.9%1.1%
Device inoperablethe device could not be used841.9%1.5%
Premature discharge of battery801.8%1.3%
Improper or incorrect procedure or method691.5%0.8%
Unexpected therapeutic results541.2%0.4%
Low battery451%0.4%
Premature end-of-life indicator431%1.3%
Use of incorrect control/treatment settings420.9%2.3%
Communication or transmission problemthe device could not communicate or transmit400.9%1.6%
Extrusion320.7%0.3%
Programming issue270.6%1.3%
Loose or intermittent connection260.6%0.6%
Human-device interface problem250.6%0.3%
Device remains implanted230.5%4.9%

FDA's device problem codes as entered on the report; one report can carry several. Generic codes such as "no apparent adverse event" are left out.

Patient problems coded

Patient problem (FDA code)ReportsShare
Seizures1,49733.1%
Therapeutic response, decreased60813.5%
Deaththe patient died; cause not stated by this term3638%
Painpain, site not specified3146.9%
Convulsion, clonic1593.5%
Apnea1042.3%
Chest painchest pain811.8%
Bradycardiaslow heart rate801.8%
Dyspneashortness of breath791.7%
Bacterial infectiona bacterial infection661.5%
Discomfortdiscomfort661.5%
Neck painneck pain631.4%
Arrhythmia581.3%
Swellingswelling581.3%
Falla fall571.3%

Patient problem codes are present mainly in reports filed since 2019 and are often blank.

In context

MeasurePulse Gen Model 103Product code LYJAll MAUDE reports
Reports4,51852,00426,136,888
Share of that pool—8.7%0%
Classified as death, per 1,000 reports85569
Classified as injury61.7%35.5%36.2%
Classified as malfunction29.8%58.7%62.3%
Filed by the manufacturer100%99.5%94.9%

Shares are of reports, not of devices in use. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."

Other brands with product code LYJ

BrandReportsLatest 12 monthsClassified as death
Programming Software7,45310%
Lead Model 3027,2591360%
Pulse Gen Model 1025,9031412.2%
Pulse Gen Model 1064,0231445.1%
Pulse Gen Model 10003,6015495.7%
Lead Model 3043,3292720.1%
Bipol Lead Model 3001,955120.1%
Pulse Gen Model Unk1,914713.6%
Ncp Pulse Generator1,272030%
Lead Model Unknown1,253461.6%
Pulse Gen Model 1011,210012.6%
Pulse Gen Model 1051,19176.7%
Vns Therapy Pulse1,064010.7%
Pulse Gen Model 102r985010.9%
Pulse Gen Model 10486449%

Ordered by report count for navigation only. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA also states that "common products may have a higher number of adverse events due to the higher total number of people using the product."

Questions about Pulse Gen Model 103 reports

How many FDA reports name Pulse Gen Model 103?

4,518 medical device reports in the openFDA MAUDE release of 28 Sep 2026, covering reports received through August 2026; 34 in the latest 12 months.

What kinds of events are reported?

injury (61.7%), malfunction (29.8%) and death (8.5%). "Event type" is how the report was classified when filed: death, injury, malfunction or other.

What device problems are coded?

insufficient device problem information (23%), device operates differently than expected (7.4%), battery problem (6.9%), high impedance (6.2%) and device displays incorrect message (2.5%). These are FDA's device problem codes as entered on the report.

Who files these reports?

manufacturer reports (100%). Manufacturers and user facilities are required to report; voluntary reports come from health professionals and the public.

Do these reports show that Pulse Gen Model 103 was at fault?

No. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA adds that "a causal relationship cannot be established between product and reactions listed in a report."

How do I report a problem with a medical device?

Through FDA MedWatch (Form FDA 3500 for health professionals and consumers), or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Device Adverse Event (MAUDE) bulk export released 28 Sep 2026, which holds reports FDA received through 31 Aug 2026. Brand, generic and manufacturer names are as written on the reports; product code names come from FDA's device classification. A report counts here when any device it lists carries this brand name after punctuation and capitalisation are normalised. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.