Commissioning of a new commercial Optically Stimulated Luminescence (OSL) dosimetry system for VMAT treatments verifications

A new commercial OSL dosimetry system was studied to analyze the possibility of its use for VMAT planning checks with end-to-end approach. The system was characterized and tested in conventional dose range (0,25-3 Gy). NanoDots (Landauer (R)), with new readout system MicroSTARii (TM), were characterized in terms of: signal decrease for repeated readings; angular, energy and dose-rate dependence. A calibration curve was obtained using 6 MV photon beam. Two VMAT plans, regarding lung lesions, were designed and optimized with: 6 MV, 600 MU/min, Eclipse TPS and Acuros XB algorithm for TrueBeam 2.5. Verification plans were created and performed both in RW3 and in anthropomorphic phantom, using end-to-end approach. The measurements in RW3 were compared to ion chamber measurement values. In anthropomorphic phantom, the OSLDs were allocated in apposite inserts, with different densities. NanoDots with new readout system MicroSTARii (TM) exhibited to be suitable for VMAT verifications with end-to-end approach in conventional fractionated treatments.