Verification of the accuracy of localization and dose based on optical surface monitoring system for tracking moving targets(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2019年第6期
- Page:
- 641-646
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Verification of the accuracy of localization and dose based on optical surface monitoring system for tracking moving targets
- Author(s):
- JIN Huaizhi1; SHI Juntian2; DAI Zhenhui1; WANG Xuetao1
- 1. Radiotherapy Area, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510006, China; 2. Department of Radiotherapy, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Keywords:
- ; Keywords: optical surface monitoring system; cone beam computed tomography; motion tracking; phantom; radiotherapic dosage; location accuracy
- PACS:
- R318；TL72
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.06.005
- Abstract:
- Abstract: Objective To evaluate the geometric accuracy of target motion measurement and dose accuracy in radiotherapy with optical surface monitoring system (OSMS) to track moving targets. Methods The positions of abdominal phantom were monitored with OSMS and cone beam computed tomography (CBCT), separately. The displacement and rotation of the phantom were achieved by moving treatment couch. Finally, the measurements of phantom position between two methods were compared. MatriXX two-dimensional ionization chamber array mounted on a respiratory motion platform was used to measure the relative dose in phantom under different tracking thresholds. The obtained doses were compared with planned doses, thereby analyzing the gamma passing rates of verification plans with different tracking thresholds. Results The difference between OSMS and CBCT system in measuring the preset displacements of phantom translation and rotation was trivial. When using OSMS gating technology, the smaller the threshold of OSMS was, the higher the gamma pass rate was, and the consistency between relative dose distribution and planned dose was better. Conclusion OSMS which has a high accuracy in monitoring the phantom surface position can be applied to the assistant positioning in radiotherapy. Using OSMS gating technology to track moving targets can improve the dose accuracy of target areas, without adding ionizing radiation to patients. OSMS is suitable for inter-fractional assistant positioning and inter-fractional target tracking.
Last Update: 2019-06-25