Dosimetric verification of flattening filter free model based on TrueBeam accelerator using ArcCheck system

Abstract

To study the feasibility of ArcCheck verification system in dosimetric verification for stereotactic radiotherapy (SRT) the stereotactic radiotherapy (SRT) with flattening filter free (FFF) model. Methods: A total of 76 cases under SRT treatment plans were introduced into ArcCheck phantom and recalculated. Threshold criteria was set as (3%, 3 mm, 10%) or (2%, 2 mm, 10%). The calculated dose distribution and the measured dose distribution of ArcCheck phantom were compared by means of distance to agree (DTA) and Gamma analysis method respectively. Results: Based on the threshold criteria (3%, 3 mm, 10%), the relative and absolute mean pass rates of SRT treatment plans by DTA and Gamma analysis were greater than 95%. Based on the threshold criteria (2%, 2 mm, 10%), the relative and absolute mean pass rates of SRT treatment plan by DTA and Gamma analysis were about 90%. The dose pass rate of Gamma analysis method was slightly higher than that of DTA analysis method (P<0.001). Conclusion: The ArcCheck verification system is a rapid and accurate method for SRT dose verification, and discrepancies are found in different analysis methods.