Abstract：Objective To explore the application feasibility of Mobius automatic verification system in the verification of volumetric
modulated arc therapy (VMAT). Methods A total of 90 patients receiving VMAT for tumors at different sites in the First Affiliated
Hospital of Xi’an Jiaotong University from April 2021 to January 2022 were randomly selected. Mobius and Delta4 methods were
used to verify the dosimetry differences in the target area of the two algorithms at different sites and the γ passing rate under multiple
criteria were calculated. The accuracy and feasibility of Mobius software in the verification of VMAT plans for different anatomical
sites were evaluated. Results The discrepancies of two algorithms of verification systems the in mean dose and 90% coverage of the
planning target volume all met the requirements of clinical dosimetric differences (<3%), and the difference between different sites
was statistically significant (P<0.05), of which the dose discrepancies in the pelvis was the smallest. When the 3%/3 mm criteria
was used, the VMAT γ passing rates of the two verification devices could meet the clinical verification requirements (γ>95%). The
γ passing rate of two systems in the criteria of 3%/3 mm, 3%/2 mm, 2%/2 mm had a good consistency (P>0.05) except the chest
VMAT plan. But the validation failed to pass the 2%/2 mm clinical standard (γ<90%). Conclusion When utilizing the 3%/3 mm γ
passing rate evaluation standard, the Mobius automatic verification system had a good consistency with the Delta4 verification device
based on the phantom, however, the deviations between different anatomical site should be noted.
西安交通大学第一附属医院 放疗科，陕西 西安 710061. Mobius自动验证系统在容积旋转调强放疗验证中的应用研究[J]. 中国医疗设备, 2023, 38(9): 31-35.
YUAN Wei, ZHANG Yuemei, LU Yongkai, HE Ruixin, TANG Fengwen, LI Yi. Research on Application of Mobius Automatic Verification System in the Verification of
Volumetric Modulated Arc Therapy. China Medical Devices, 2023, 38(9): 31-35.
