Commissioning and Quality Assurance of Catalyst⁺ HD Surface-guided Radiotherapy on TrueBeam HyperArc Linear...

In this study, we describe and critically review our experience in the commissioning of the surface-guided radiation therapy (SGRT) system from C-RAD (Uppsala, Sweden), integrated with a Varian TrueBeam HyperArc linear accelerator (LINAC).

The C-RAD SGRT system was commissioned according to the guidelines of the American Association of Physicists in Medicine Task Group 147 and the European Society for Radiotherapy and Oncology-Advisory Committee for Radiation Oncology Practice report. The commissioning tests included the isocenter, camera thermal drift, reproducibility, static localization accuracy with a 6-degree-of-freedom (DOF) couch, dynamic gating delivery, and an end-to-end test. The tools and phantoms employed for this verification included: (a) Sentinel 4DCT daily check device, (b) Catalyst⁺ HD daily check device, (c) Penta-guide, (d) gating phantom, (e) calibration board, (f) Winston-Lutz phantom, and (g) the Little John anthropomorphic phantom.

The reproducibility of both the Sentinel 4DCT and Catalyst⁺ HD cameras demonstrated accuracy within ± 1 mm. The radiation isocenter measurements for both the Sentinel 4DCT and Catalyst⁺ HD cameras were found to be <1 mm, well within the recommended reports of the relevant international guidelines. The static localization accuracy of the Catalyst⁺ HD camera with a 6DOF couch was determined to be 0.15 ± 0.13 mm, 0.42 ± 0.23 mm, and 0.20 ± 0.15 mm for the vertical, longitudinal, and lateral directions, respectively. The rotational accuracy for roll, pitch, and yaw was found to be 0.05°±0.05°, 0.12°±0.18°, and 0.13°±0.10°, respectively. All results were within the tolerances recommended by the international recommendations and highlight the accuracy and precision of the C-RAD SGRT system in conjunction with the TrueBeam HyperArc LINAC.

The newly installed advanced C-RAD SGRT systems have been successfully integrated with the Varian TrueBeam LINAC for clinical use, marking a significant milestone as the first deployment of SGRT technology of its kind in India.