MAUDE Adverse Event Report: VIEWRAY, INCORPORATED MRIDIAN LINAC SYSTEM; MEDICAL CHARGED-PARTICLE RADIATION THERAPY SYSTEM

Model Number 20000-01

Device Problem Radiation Overexposure (3017)

Patient Problem Unintended Radiation Exposure (4565)

Event Date 01/19/2023

Event Type  malfunction  

Event Description

A user of viewray's mridian linac system reported an issue with the a3i delivery calendar.The site revised a patient's plan after two (2) fractions.The revised plan was placed into a new delivery calendar.The remaining fractions of the original delivery calendar were locked on the treatment planning system (tps) as per the mridian linac operator's manual (l-0240), but when the therapist went to treat the patient they noticed that the locked fractions within the original plan were still available for delivery.The site indicated that this is different behavior as compared to the way the delivery calendar used to perform in the v2 software version.With the a3i software, the site was unclear per the mridian linac operator's manual (l-0240) how to deactivate unused fractions in the partially delivered delivery calendar and also how to deactivate some fractions on the new delivery calendar.

Manufacturer Narrative

The root cause of the event was identified as the mridian linac operator's manual (l-0240) contains instructions regarding how to disable fractions which is inconsistent with the software's implementation.The instructions were carried over from v2.0 software version in error, the manual should describe the a3i and 3.0 workflow rather than the v2.0 process.The investigation into this issue is as follows: 1.For the a3i and v3.0 software, when a fraction is locked on the tps the fraction "appears" to be locked as per the l-0240 rev.B "operator's manual for the mridian a3i system version 5.5.2.When opening the same patient's fraction calendar on the tds, though, the fraction does not appear locked as described in the l-0240 rev.B "operator's manual for the mridian a3i system version 5.5.3.A review of l-0240 rev.B "operator's manual for the mridian a3i system version 5.5" has been performed for the fraction lock functionality.For the fraction locking function l-0240 rev.B says "you can lock fractions so they cannot be delivered unless unlocked by an authorized user".There is no mention as to the fraction locking function working on the tps but not the tds.4.The complaint describes a potential issue that was avoided due to the existing mitigations in the system.No patient was mistreated, no harm occurred, and no locked fractions were delivered because the mitigations for plan selection and approval did as they were designed.5.When the physician adapts and creates a replacement plan after starting the first plan, there is no requirement to lock the remaining fractions of the first plan.There are multiple ways to deal with this situation, and locking the remaining fractions is just one potential method.None of the methods are required to be used.The hospital workflow determines how the situation is managed in the system.

• Brand Name: MRIDIAN LINAC SYSTEM
• Type of Device: MEDICAL CHARGED-PARTICLE RADIATION THERAPY SYSTEM
• Manufacturer (Section D): VIEWRAY, INCORPORATED; 815 e. middlefield road; mountain view CA 94043
• Manufacturer (Section G): VIEWRAY, INCORPORATED; 815 e. middlefield road; mountain view CA 94043
• Manufacturer Contact: patrick jones ; 815 e. middlefield road; mountain view, CA 94043 ; 7196495345
• MDR Report Key: 16311656
• MDR Text Key: 309509867
• Report Number: 3011233554-2023-00001
• Device Sequence Number: 1
• Product Code: IYE
• UDI-Device Identifier: 10868029000305
• UDI-Public: 011086802900030511200218
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K212958
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Health Professional
• Reporter Occupation: Physician
• Remedial Action: Relabeling
• Type of Report: Initial
• Report Date: 02/06/2023

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 02/07/2023
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: 20000-01
• Device Catalogue Number: 20000-01
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 01/19/2023
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 11/18/2022
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Reuse
• Patient Sequence Number: 1
• Patient Outcome(s): Other