14. Commissioning of the RayStation treatment planning system and dosimetric comparison with Pinnacle

Abstract

Purpose To present our results regarding the commissioning of the RayStation TPS and to compare its dosimetric accuracy with the clinical Pinnacle TPS. Methods A 6 MV beam quality of an Elekta Synergy was considered for modeling in RayStation. The dose calculation accuracy was tested in several situations. Firstly, measured PDD and profiles were compared with calculations using the 1D-gamma analysis. Secondly, using the test fields from the ESTRO booklet No. 7, absolute point doses were measured in a water phantom and compared with calculated values. Then, IMRT and VMAT techniques were tested performing pre-treatment verifications with the PTW-Octavius4D system. For this purpose, the AAPM TG-119 test cases as well as 20 clinical patients with various treatment sites were considered. The agreement between measurements and calculations was assessed with 3D-gamma analysis. Finally, 10 VMAT clinical cases optimized with Pinnacle were recalculated in RayStation. Dose distributions from both TPSs were compared with measurements. Results maximum values of 1D-gamma confidence-level were 0.6 for PDDs (2%-2 mm, local normalization, Table 1 ) and 0.75 for profiles (3%-2 mm, local normalization). Absolute point dose measurements agreed with calculated values within 1.5%. 3D-gamma pass-rates for the TG-119 cases and patient-specific verifications were within the ranges [97.2%-99.7%] and [89.0%-97.5%] for 3%-3 mm global and local normalization, espectively. Absolute differences between average gamma pass-rates of patient-specific verifications were 0.1% (3%-3 mm, global normalization) and 1.1% (3%-3 mm, local normalization). These differences were not statistically significant (minimum p-value for a Wilcoxon-signed-rank test was 0.51, Fig. 1). Conclusions RayStation was commissioned for a 6 MV beam quality of an Elekta Synergy. The dosimetric accuracy was tested in several situations, including standard international protocols. The agreement between measurements and calculations was clinically acceptable. Furthermore, RayStation accuracy was comparable with the clinically established Pinnacle TPS.