MAUDE Adverse Event Report: NIHON KOHDEN CORPORATION NEUROMASTER G1; NEURAL FUNCTION MEASURING SYSTEM

Model Number	DC-200B
Medical Device Problem Codes	Application Program Problem (2880); Unintended Application Program Shut Down (4032)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	02/07/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
The biomedical engineer (bme) reported that they are having a similar issue as in complaint (b)(4).They were in the middle of obtaining baseline data when the mee-2000a shutdown.All the signals went black out of nowhere, and then there was an error message for a main unit failure.Then the program would not close, and it kept stimulating sseps when trying to close it.They are able to reboot it, and it seems to resolve the issue.However, the issue reoccurs.They do not know if it was in patient use.No patient harm reported.Nihon kohden continues to investigate the reported event.Nihon kohden will submit a supplemental report in accordance with 21 cfr section 803.56 when additional information becomes available.
Event or Problem Description
The biomedical engineer (bme) reported that they are having a similar issue as in complaint (b)(4).They were in the middle of obtaining baseline data when the mee-2000a shutdown.All the signals went black out of nowhere, and then there was an error message for a main unit failure.Then the program would not close, and it kept stimulating sseps when trying to close it.They are able to reboot it, and it seems to resolve the issue.However, the issue reoccurs.They do not know if it was in patient use.No patient harm reported.
Additional Manufacturer Narrative
The biomedical engineer (bme) reported that they are having a similar issue as in complaint (b)(4).They were in the middle of obtaining baseline data when the mee-2000a shutdown.All the signals went black out of nowhere, and then there was an error message for a main unit failure.Then the program would not close, and it kept stimulating sseps when trying to close it.They are able to reboot it, and it seems to resolve the issue.However, the issue reoccurs.They do not know if it was in patient use.No patient harm reported.Investigation conclusion: cause and additional information: the phenomenon could not be reproduced on the actual product where the phenomenon occurred.Nka requested that the investigation be suspended because the phenomenon could not be reproduced.Countermeasures to prevent recurrence: since the necessary information for the investigation was not provided, no recurrence prevention measures will be implemented.Additional device information: d10: concomitant medical device: model: mee-2000a.Sn: (b)(6).Additional information: b4 date of this report.G3 date received by manufacturer.G6 type of report.H2 if follow-up, what type? h3 device evaluated by manufacturer.H6 event problem and evaluation codes.H11 additional manufacturer narrative.
Event or Problem Description
The biomedical engineer (bme) reported that they are having a similar issue as in complaint (b)(4).They were in the middle of obtaining baseline data when the mee-2000a shutdown.All the signals went black out of nowhere, and then there was an error message for a main unit failure.Then the program would not close, and it kept stimulating sseps when trying to close it.They are able to reboot it, and it seems to resolve the issue.However, the issue reoccurs.They do not know if it was in patient use.No patient harm reported.

• Brand Name: NEUROMASTER G1
• Common Device Name: NEURAL FUNCTION MEASURING SYSTEM
• Manufacturer (Section D): NIHON KOHDEN CORPORATION; attn: shama mooman; 1-31-4 nishiochia; shinjuku-ku, tokyo 161-8 560; JA 161-8560
• Manufacturer (Section G): NIHON KOHDEN TOMIOKA CORPORATION; attn: shama mooman; 1-1 tajino; tomioka city, gunma 370-2 314; JA 370-2314
• Manufacturer Contact: shama mooman ; seibu bldg 2, 4th floor 1-11-2; kusunokidai tokorozawa, saitama 359-8-580 ; JA 359-8580
• MDR Report Key: 21531882
• Report Number: 8030229-2025-04754
• Device Sequence Number: 12775055
• Product Code: GWF
• UDI-Device Identifier: 04931921118054
• UDI-Public: (01)04931921118054
• Combination Product (Y/N): N
• Initial Reporter State: TN
• Initial Reporter Country: US
• PMA/510(K) Number: K142624
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: User Facility
• Initial Reporter Occupation: Biomedical Engineer
• Type of Report: Initial,Followup
• Report Date (Section B): 09/11/2025

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Model Number: DC-200B
• Device Catalogue Number: DC-200BA
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 02/14/2025
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 02/07/2025
• Supplement Date Received by Manufacturer: 09/10/2025
• Initial Report FDA Received Date: 03/05/2025
• Supplement Report FDA Received Date: 09/11/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 08/10/2023
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Reuse
• Patient Sequence Number: 1
• Concomitant Medical Products and Therapy/Usage Dates: MEE-2000A. SN (B)(6).; NA.
• Patient Sex: Unknown