Abstract

Info

Title:: Application of statistical process control in mechanical performance monitoring of linear accelerators

Author(s):: LIANG Lan; XIAO Qing; ZHANG Xiangyu; SONG Ying; LI Guangjun; BAI Sen; Department of Radiation Oncology, West China Hospital of Sichuan University, Chengdu 610041, China

Keywords:: Keywords: medical linear accelerator statistical process control machine performance chech quality assurance

Abstract:: Objective To analyze the long-term performance of the medical linear accelerator, monitor the accelerator state and evaluate the mechanical performance of the accelerator by statistical process control method. Methods The daily quality assurance data from June 2019 to April 2021 were collected. The control charts for individuals were draw to monitor the process state, and the process quality was evaluated using process capability indexes (Cpk and Cp). Results The mechanical accuracy of the accelerator was obviously better than the specification limits recommended by the current manufacturer, while almost all mechanical indexes had process shifts to varying degrees according to the results of control chart. The process capability analysis showed that the Cpk and Cp of all test items were greater than 1.33, indicating excellent process quality. Conclusion When accelerator performance meets the current machine performance chech specifications, process shifts may still occur. The statistical process control method can detect the shifts immediately, and process capability index can evaluate the process quality effectively, guiding the quality management and clinical decision making.