MAUDE Adverse Event Report: ELEKTA SOLUTIONS AB MOSAIQ; ACCELERATOR, LINEAR, MEDICAL

Lot Number	VERSION 2.83.053
Medical Device Problem Code	Computer Software Problem (1112)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	08/05/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
H4: manufacturing date is not on the label, but it is known so field h4 has been completed with this information.The manufacturer's investigation is on-going and further information will be provided once the investigation has completed.
Event or Problem Description
The error consisted of the application of a radiotherapy session based on the treatment plan of another patient.Technicians selected the wrong patient in the mosaiq system.They did not follow the security procedures of verifying patient identification.
Additional Manufacturer Narrative
H6 updated.H11 updated: the investigation was completed by conducting a thorough evaluation of the product and the reported information.The customer reported that the error consisted of the application of a radiotherapy session based on the treatment plan of another patient.Technicians selected the wrong patient in the mosaiq system.They did not follow the security procedures of verifying patient identification.It was ascertained from the logs that the plan belonging to patient a was not delivered on (b)(6) 2025.However, the customer states that patient a was mistakenly treated with the plan of a different patient (patient b) in error.There is no way to confirm from the logs which patient was physically in the room at the time a particular treatment was given.Although the logs for the same day do show that the plan for patient b was delivered around 23.55 to 23.59 which is approximately within an hour of the timeframe patient a may have typically received treatment.The mistreatment of patient a is due to abnormal use and elekta physics assessed this as a serious radiation overdose.It is the user's responsibility to verify the patient (photo id display in mosaiq could help) and confirm the plan is correct prior to irradiating beam.Mosaiq did not have any malfunction and worked as designed and intended.

• Brand Name: MOSAIQ
• Common Device Name: ACCELERATOR, LINEAR, MEDICAL
• Manufacturer (Section D): ELEKTA SOLUTIONS AB; hagaplan 4; stockholm, 113 6 8; SW 113 68
• Manufacturer (Section G): ELEKTA SOLUTIONS AB; 400 perimeter center terrace; suite 50; atlanta GA 30346
• Manufacturer Contact: cornerstone; london road; crawley, west sussex RH10 -9BL
• MDR Report Key: 22963452
• Report Number: 3015232217-2025-00054
• Device Sequence Number: 8529613
• Product Code: IYE
• UDI-Device Identifier: 00858164002367
• UDI-Public: (01)00858164002367(10)2.83.053
• Combination Product (Y/N): N
• Initial Reporter Country: BR
• PMA/510(K) Number: K183034
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Health Professional,User Facility
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 10/28/2025

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?: No
• Operator of Device: Health Professional
• Device Lot Number: VERSION 2.83.053
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/08/2025
• Supplement Date Received by Manufacturer: Not provided
• Initial Report FDA Received Date: 09/04/2025
• Supplement Report FDA Received Date: 10/28/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 08/31/2021
• 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
• Patient Sex: Unknown