Optical Surface Monitoring System{Align RT Plus} This is used on Varian's TrueBeam EDGE; Radiology: The AlignRT Plus system is indicated for use to position and monitor patients relative to the prescribed treatment isocentre, and to Withhold the beam automatically during radiation delivery.

Varian Medical Systems has received reports that unintended changes were made to planned couch parameters, specifically the couch rotation parameter, during patient set-up. This can occur when a user sets a different couch rotation from the plan couch rotation while performing patient alignment with Optical Surface Monitoring System [OSMS].

The firm, Visionrt, sent an "URGENT MEDICAL DEVICE CORRECTION NOTIFICATION-URGENT FIELD SAFETY NOTIFICATION" letter dated June 24, 2016 to all affected customers. Letters describe the product, problem and actions to be taken. The customers were instructed as follows: DO NOT USE the "Move Couch" function if the couch rotation value set in the AlignRT device DOES NOT match the planned couch rotation for the treatment field; retain a copy of this document along with your most current product labeling; pass the letter to all those who need to be aware of it within their organization; always confirm that the patient is correctly aligned prior to commencing treatment; is not required to return their devices; promptly inform Vision RT if they believe that patient harm occurred, and complete Appendix 1- Customer Acknowledgment Response and return it via email to [email protected]. Should you have any queries on this letter, please do not hesitate to contact Vision RT by telephone on +44 20 83464300 (866-778-2379 from the US) or as per http://www.visionrt.com/contact/details.