Oh Se An, Yea Ji Woon, Kim Sung Kyu
Department of Radiation Oncology, Yeungnam University Medical Center, Daegu, Korea.
Institute of Medical Science, Yeungnam University College of Medicine, Daegu, Korea.
PLoS One. 2016 May 26;11(5):e0156357. doi: 10.1371/journal.pone.0156357. eCollection 2016.
Respiratory-gated radiation therapy (RGRT) is used to minimize the radiation dose to normal tissue in lung-cancer patients. Although determining the gating window in the respiratory phase of patients is important in RGRT, it is not easy. Our aim was to determine the optimal gating window when using a visible guiding system for RGRT. Between April and October 2014, the breathing signals of 23 lung-cancer patients were recorded with a real-time position management (RPM) respiratory gating system (Varian, USA). We performed statistical analysis with breathing signals to find the optimal gating window for guided breathing in RGRT. When we compared breathing signals before and after the breathing training, 19 of the 23 patients showed statistically significant differences (p < 0.05). The standard deviation of the respiration signals after breathing training was lowest for phases of 30%-70%. The results showed that the optimal gating window in RGRT is 40% (30%-70%) with respect to repeatability for breathing after respiration training with the visible guiding system. RGRT was performed with the RPM system to confirm the usefulness of the visible guiding system. The RPM system and our visible guiding system improve the respiratory regularity, which in turn should improve the accuracy and efficiency of RGRT.
呼吸门控放射治疗（RGRT）用于将肺癌患者正常组织所受辐射剂量降至最低。尽管在RGRT中确定患者呼吸阶段的门控窗口很重要，但并非易事。我们的目的是确定在使用可视引导系统进行RGRT时的最佳门控窗口。2014年4月至10月期间，使用实时位置管理（RPM）呼吸门控系统（美国瓦里安公司）记录了23例肺癌患者的呼吸信号。我们对呼吸信号进行统计分析，以找到RGRT中引导呼吸的最佳门控窗口。当我们比较呼吸训练前后的呼吸信号时，23例患者中有19例显示出统计学上的显著差异（p < 0.05）。呼吸训练后，呼吸信号在30% - 70%阶段的标准差最低。结果表明，在使用可视引导系统进行呼吸训练后，就呼吸重复性而言，RGRT中的最佳门控窗口为40%（30% - 70%）。使用RPM系统进行RGRT以确认可视引导系统的有效性。RPM系统和我们的可视引导系统改善了呼吸规律性，进而应提高RGRT的准确性和效率。
