Effects of respiratory baseline fluctuations on performance of breathing predictive filter in respiration-gated radiotherapy(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2022年第2期
- Page:
- 152-156
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Effects of respiratory baseline fluctuations on performance of breathing predictive filter in respiration-gated radiotherapy
- Author(s):
- ZHENG Jiajun; SUN Li; WANG Qi; MU Zhongde; ZHAI Zhenyu
- Department of Medical Physics and Technology, Jiangsu Cancer Hospital/Jiangsu Institute of Cancer Research/the Affiliated Cancer Hospital of Nanjing Medical University, Nanjing 210000, China
- Keywords:
- Keywords: real-time position management phase-based respiration gating breathing predictive filter respiratory baseline baseline fluctuation residual motion
- PACS:
- R815.6
- DOI:
- DOI:10.3969/j.issn.1005-202X.2022.02.004
- Abstract:
- Abstract: Objective To evaluate the effect of baseline fluctuations of patients breathing on the performance of breathing predictive filter in respiration-gated radiotherapy based on Varian real-time position management (RPM) system. Methods The reference respiratory waveforms and residual motions of 20 cases of RPM phase-based respiration-gated radiotherapy were analyzed, as well as the respiratory waveforms and residual motions in a total of 146 treatments. (1) After Savitsky-Golay smoothing, peak detection and abnormal point elimination for the respiratory waveforms (including reference and treatment), the respiratory baseline was obtained. Standard deviation was calculated as an index to measure the strength of baseline fluctuations, and the relative deviation of baseline fluctuations relative to the reference baseline fluctuations during each treatment was calculated. (2) The standard deviation of residual motions (including reference and treatment) was used as an indicator to measure the strength of residual motion, and the relative deviation of residual motion relative to the reference residual motion during each treatment was calculated. (3) Pearson correlation analyses on the baseline fluctuation deviations and residual motion deviations were carried out. Results The minimum and maximum values ?#8203of the deviations of respiratory baseline fluctuations in 146 treatments were -61.0%, 752.3%, and the quartiles were 42.8%, 90.3%, 161.7%. For the deviations of residual motions, the minimum and maximum values were -74.8%, 174.0%, and the quartiles were -7.8%, 15.1%, 48.8%. The correlation coefficient between residual motion deviations and baseline fluctuation deviations was 0.544, and the P value was much less than 0.01, indicating statistical significance. The linear fitting coefficient was 0.2. Conclusion Under the current technical conditions of RPM phase-based respiration-gated technology, the actual residual motion deviation of the patient during treatment is significantly linearly related to the baseline respiratory fluctuation deviation. Every 100% baseline fluctuation deviation can lead to an average of 20% residual motion deviation. Therefore, an effective quality control program needs to be formulated in clinic for avoiding respiratory baseline deviations during treatment.
Last Update: 2022-03-07