Mevion S250 Proton Radiation Therapy System Software Defect Recall
Mevion Medical Systems is recalling six MEVION S250 Proton Radiation Therapy Systems due to a software defect that causes 2D contour projections to appear off from their true position.
The agency’s classification
FDA (Devices): Class II
Class II is a situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences, or where the probability of serious adverse health consequences is remote.
This is the agency’s own classification, taken from its notice. The severity score below is our assessment, not the agency’s. How recall classes work
What this means for you
Our assessment, not the agency’s: severity 3/5 (High).
Real risk of harm even if no illness or injury has been reported yet. Stop using the product and follow the agency's guidance.
Our severity reasoning: The recall involves a medical device with a software defect that affects the accuracy of radiation therapy planning. While no injuries are reported, the potential for misalignment in a high-risk treatment modality fits the criteria for a risk-of-harm product where injury has not yet been reported.
Plain-English summary
Mevion Medical Systems, Inc. is recalling six MEVION S250 Proton Radiation Therapy Systems. The affected units have serial numbers ranging from S250-0001 through S250-0006. These systems were distributed nationwide in the states of Florida, Missouri, New Jersey, Ohio, and Oklahoma.
The recall is due to a software defect in the Verity system involving the 2D projection of contours. This defect causes structures to appear off from their true position in the DRR and the radiograph. The error increases with the distance of the structure from the isocenter.
Healthcare facilities that have purchased or received these specific serial numbers should contact Mevion Medical Systems, Inc. for instructions on how to resolve the software defect. Consumers should not use the affected systems until the issue is addressed by the manufacturer.
The recalled product
- Product
- MEVION S250 Product Usage: Proton Radiation Therapy System
- Manufacturer
- Mevion Medical Systems, Inc.
- Affected units
- 6
Is your product affected?
Check your packaging against the codes below. If any of them match, the product is part of this recall.
Lot numbers (1)
- Serial Numbers: S250-0001 through S250-0006
Distribution
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