ESTRO 2024 - Abstract Book

S3318

Physics - Detectors, dose measurement and phantoms

ESTRO 2024

Thus, for SRS and SBRT treatments, where high accuracy is of paramount importance, caution must be used if and when using electronic devices. Following these results we decided to maintain our current standard of film dosimetry for these treatments.

Keywords: SBRT, Quality Assurance, Film Dosimetry

2259

Digital Poster

Can PTW Octavius ® 1600 SRS be used to verify Varian SRS HyperArc ® and SABR plans?

Max Morris, Alison Starke, Jacqueline Poxon, Niall MacDougall

Barts Health NHS Trust, Radiotherapy, London, United Kingdom

Purpose/Objective:

Figure 1 PTW Octavius® 1600 SRS in a 4D rotation phantom.

We evaluated the PTW Octavius ® 1600 SRS detector array with 4D modular rotation phantom and Octavius ® Top SRS for the patient specific quality control (PSQC) of Varian SRS and SABR plans. Specifically designed for non-coplanar SRS applications, coplanar measurements are reconstructed to a 3D measured dose volume by applying the couch angles of the treatment plan. However, a dose-rate and field size dependence has been previously demonstrated for this device for 6FFF beams, impacting the ability to use the device for PSQC of multi-metastases brain plans [1]. The aim of this study was to extend this work by evaluating the Octavius 1600 SRS array for the PSQC of both 6FFF and 10FFF SABR and SRS Hyperarc ® plans.

Material/Methods: