SU-E-T-215: A Technique for Treating Patients outside the Mosaiq R&V System for TrueBeam Users (or 4DTC)

When the record and verify (R&V) system (Mosaiq, Elekta Medical Systems) is unavailable to send information to the treatment console of the linear accelerator (Varian Clinac, Varian Medical Systems), treatment is manually delivered by entering parameters into the treatment console and loading backed up MLC files. The new linear accelerator, the TrueBeam (Varian Medical Systems) lacks the ability to manually deliver treatment by entering machine parameters into the treatment console.

The TrueBeam can only deliver treatments using the R&V system or loading DICOM RT plan files directly in File Mode. Every time a prescription site is sent from the R&V system to the accelerator, a DICOM RT plan file is created by the R&V system. A script was created that reads the headers of these files, copies them to the treatment console and renames them in an identifiable form. At the end of each treatment day, the script is executed transferring only the DICOM RT plan files created that treatment day. A contingency report is then generated from the R&V system, which contains machine parameters for all fields for all patients under treatment. When the R&V system is unavailable the RT plan files are opened in file mode, and the machine parameters are verified using the contingency report before delivery. This system was tested on a cohort of patients. Each patient's plan was opened in file mode and the machine parameters were verified against the patient's planned treatment in the R&V system.

All files opened in file mode were identical to the information stored in the R&V system. This was tested both on the TrueBeam and accelerators having the 4DTC.

Our technique was validated and is an alternative method for delivering treatment when the R&V system is unavailable.