Physics Biology Technique
Commissioning and testing of treatment planning system model of an Edge accelerator with a high-definition multi-leaf collimator
Yangguang Ma, Tao Wang, Jinyan Hu, Zheng Zhang, Fangna Wang, Xuemin Wang, Yuexin Guo
Published 2019-02-15
Cite as Chin J Radiat Oncol, 2019, 28(2): 113-118. DOI: 10.3760/cma.j.issn.1004-4221.2019.02.007
Abstract
ObjectiveTo investigate the commissioning and testing of the Eclipse model of an Edge accelerator with high-definition multi-leaf collimator (HD-MLC).
MethodsThe percentage depth dose (PDD), profile, output factor measured by Razor and CC13 were statistically compared with the standard data. Penumbra, transmission factor (TF), leakage, concave-convex groove, accuracy of movement and dosimetry leaf gap (DLG) were measured with EBT3, electronic portal image device (EPID) and PTW SRS1000&SRS1500. The optimal DLG/TF was acquired when the γ pass rate of test cases was the highest. The point dose of regular fields, intensity-modulated radiation therapy (IMRT) and volume-modulated radiation therapy (VMAT) was verified with FC65-G. The planar dose of these case was verified with Octavius 4D and EBT3.
ResultsThe measured PDD data were consistent with the standard data. The measured penumbra of 3 cm and 4 cm square fields was smaller, whereas that of 6 cm square field was larger than the standard values. The left and right edge, field size, center of the field were distributed within the range of -1.0-0.4 mm、0.2-1.7 mm, -0.3-1.9 mm and -0.1-0.8 mm, respectively. The mean penumbra of the left and right MLC in different positions were (2.5±0.042) mm and (2.7±0.005) mm. The leakage of MLC was 0.009-0.016. The measured DLG/TF was 0.1861 cm/0.0116 and the optimal DLG/TF was 0.015 cm/0.014. The differences of point dose of all the test cases except the one which was in the low-dose area were within ±3%. Local and global γ pass rates of all IMRT were 79.81%-100% and 96.3%-100% (3%/3 mm), 71.3%-98.9% and 94.3%-99.8% for VMAT cases.
ConclusionsThis method can accurately test and commission the Eclipse treatment planning model of Edge Linac equipped with HD-MLC.
Key words:
Commission of treatment planning model; Small-field measurement; HD-MLC feature parameter testing; Edge Linac
Contributor Information
Yangguang Ma
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
Tao Wang
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
Jinyan Hu
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
Zheng Zhang
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
Fangna Wang
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
Xuemin Wang
Department of Radiotherapy Hospital Unit Radiation Therapy, Shanxi Provincial Tumor Hospital, Xi′an 710061, China
Yuexin Guo
Department of Radiation Oncology, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
