Proteus 235, ProteusPLUS or Proteus ONE produces and delivers a proton beam for the treatment of patients with localized tumors and other conditions susceptible to treatment by radiation.

Reason: When switching from Pencil Beam Scanning treatment mode to Uniform Scanning treatment mode, the tuning setpoints of the scanning magnets are not always taken into account when the proton beam is requested. The mismatch between the setpoint and feedback leads to an error message. Depending on user action, two scenarios are possible: 1. The user resumes the treatment field without analyzing the cause for the error message. This may lead to under-irradiation. 2. The user reboots the Scanning Magnets Power Supply Electronic Unit. This may lead to delay in patient treatment and the patient may need to be re-aligned, which leads to an additional X-ray dose.

Code information: Affected version: PTS-7.X.X and PTS-8.X.X Serial numbers PAT.107 (EU); PAT.108, PAT.112, PAT.113, PAT.116 (US)

Distribution pattern: Consignees in four states: VA, IL, NJ, and WA. One consignee located in Germany.