Installation product acceptance of Varian Halcyon accelerator
10.3760/cma.j.cn113030-20191108-00456
- VernacularTitle:瓦里安Halcyon加速器的安装验收测试
- Author:
Qiaoqiao HU
1
;
Hao WU
;
Fan JIANG
;
Ruoxi WANG
;
Meijiao WANG
;
Yibao ZHANG
Author Information
1. 北京大学肿瘤医院暨北京市肿瘤防治研究所放疗科恶性肿瘤发病机制及转化研究教育部重点实验室 100142
- Keywords:
Halcyon accelerator;
Installation product acceptance;
Quality assurance
- From:
Chinese Journal of Radiation Oncology
2021;30(7):712-716
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To understand the components, performance, acceptance test and quality assurance (QA) protocols of the new Varian Halcyon accelerator through the procedures of installation product acceptance (IPA).Methods:Per Varian IPA protocol, TG-142 for LINAC and TG-148 for tomotherapy QA protocols, the software license, safety interlock, mechanical accuracy, dosimetric performance and imager system were checked thoroughly. Some parameters were benchmarked to the conventional TrueBeam system.Results:The system has been fully licensed. Safety interlock was normal. Mechanical accuracy: The maximum deviation of beam stability per gantry rotation was 1.13%. The size of isocenter was>0.59mm. The offsets of MV imager, collimation rotation and absolute gantry rotation were 0.09mm, -0.21° and 0.11°, respectively. The maximum offsets of couch, virtual-to-isocenter were 0.15mm (vertical) and -0.04mm (vertical), respectively. Beam performance: The depth deviation of maximum dose was 0.1cm. The offset of percentage depth dose at 10cm was 0.5%. The maximum deviations of off-axis-intensity, symmetry, and repeatability were 0.9%, 0.94% and -0.44%, respectively. MV imager: The dark field mean pixel value, noise, corrected pixels, defective lines, sensitivity and linearity disparity of dose were 614, 4.4, 3626, 0, 19177, and 0.47%, respectively. All values were within the range of tolerance. Visual check of contrast resolution and small object detection was all satisfactory.Conclusions:Without Halcyon-specific TG report or guidelines, manufacture-provided IPA manual can be helpful with the installation of acceptance and QA protocols. IPA has been successfully performed for Halcyon at Peking University Cancer Hospital. The automated workflow improves the clinical efficiency by simplifying the operations.