An Analysis Method of Dose Error Caused by the Couch Tilt of CT Simulation Machine
Radiation Science and Technology
Volume 6, Issue 3, September 2020, Pages: 27-31
Received: Aug. 17, 2020;
Accepted: Aug. 25, 2020;
Published: Sep. 10, 2020
Views 227 Downloads 99
Yang Bo, Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
Zhang Jing, Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
Li Lei, Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
Liu Xiaolong, Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
Pang Haowen, Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
Purpose: If the horizontal plane is inconsistent between computer tomography (CT) couch and line accelerator (LA) couch, the position of the isocenter point in the radiotherapy treatment planning system (TPS) should deviate from that of it on the accelerator couch board. Then, the actual dose distribution was different from the radiotherapy plan we designed in TPS. This paper introduces a method to evaluate the dose deviation caused by the tilt of CT couch. Methods: We calculated the isocenter points of the position coordinates both in CT couch and LA couch, and compared the dose distribution when the twopositions of isocenter points were applied in radiotherapy plan independently in TPS. The dose distribution difference of a breast radiotherapyplan was analyzed as a demonstration with this method. Results: The distance between the two isocenter positions increased with angle of CT couch. The tilt of the couch had an impact on the dose distribution, especially in larynx's maximum dose parameter. Conclusion: This method could quantitatively analyze the dose distribution deviationcaused by the tilt of CT couch plate. The results can provide a valuable suggestion for clinical medical strategy.
An Analysis Method of Dose Error Caused by the Couch Tilt of CT Simulation Machine, Radiation Science and Technology.
Vol. 6, No. 3,
2020, pp. 27-31.
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