相位式呼吸门控放疗中门控窗口的选择方法研究  

Study on selection method of gating windows in phase-based respiratory-gating radiotherapy

作　　者：郑佳俊 翟振宇[1] 蒋明华[1] 孙丽[1] ZHENG Jia-jun;ZHAI Zhen-yu;JIANG Ming-hua;SUN Li(Jiangsu Cancer Hospital,Jiangsu Institute of Cancer Research,the Affiliated Cancer Hospital of Nanjing Medical University,Nanjing 210009,China)

机构地区：[1]江苏省肿瘤医院,江苏省肿瘤防治研究所,南京医科大学附属肿瘤医院,南京210009

出　　处：《医疗卫生装备》2022年第3期51-55,共5页Chinese Medical Equipment Journal

基　　金：江苏省卫健委干部保健科研项目(BJ19031)。

摘　　要：目的:提出一种相位式呼吸门控放疗中门控窗口的选择方法。方法:采用数字表法随机选取某院已完成基于实时位置管理(real position management,RPM)系统的相位式呼吸门控放疗的38例患者。针对每个患者的参考呼吸波形,分别计算所有可选的100(10×10)个窗口内的呼吸信号标准差,作为衡量该窗口内呼吸运动稳定性的指标。在100个可选窗口中,将与临床所选窗口占空比相同但呼吸信号标准差最小的窗口作为建议窗口。比较并分析38例患者的临床窗口和基于该方法选择的建议窗口之间的呼吸信号标准差差异,并进行配对样本t检验。结果:38例患者中,临床窗口的呼吸信号标准差为(0.114±0.050)cm,建议窗口的呼吸信号标准差为(0.108±0.049)cm,二者相比有统计学差异(P=0.009)。27例患者的建议窗口与临床窗口一致,其余11例患者的建议窗口与临床窗口相比呼吸信号标准差有所减小(窗口内呼吸运动稳定性提高),其中1例下降幅度超过30%,8例下降幅度在5%~30%,2例下降幅度在5%以内。结论:在相位式呼吸门控放疗中,基于窗口内的呼吸信号标准差选择门控窗口的方法可以保证和提高临床所选门控窗口的质量。Objective To propose a method for selecting the gating windows in phase-based respiratory-gating radiotherapy.Methods The digital table method was used to randomly select 38 patients who had completed phase-based respiratory-gating radiotherapy based on the real position management(RPM)system at some hospital.Based on the reference respiratory waveform of each case the standard deviation of the respiratory signal in each of all 100(10×10)alternative windows was calculated respectively as a metric to measure the stability of respiratory motion.The recommended window was designated with the same duty cycle as that of the clinically selected one and the respiratory signal having the lowest standard deviation.The differences in the standard deviations of the respiratory signals between the clinical window and the recommended window selected based on this method were compared and analyzed with a paired samples t-test in the 38 patients.Results For the 38 patients there were significant differences in the standard deviations of the respiratory signals in the clinical window(0.114±0.050)cm and in the recommended window(0.108±0.049)cm(P=0.009).The recommended window was consistent with the clinical window in 27 patients,and the standard deviations of the respiratory signals decreased in the remaining 11 patients compared to the clinical window(with increased stability of respiratory movements within the window),with one case decreased by more than 30%,eight cases decreased by 5%to 30%and two cases by 5%or less.Conclusion In phase-based respiratory-gating radiotherapy the window selection quality assurance method based on respiratory signal standard deviation analysis guarantees and improves the quality of clinically selected gating windows.[Chinese Medical Equipment Journal,2022,43(3):51-55]

关 键 词：呼吸门控放疗 窗口选择 呼吸信号标准差 门控窗口 临床窗口 建议窗口 

分 类 号：R318[医药卫生—生物医学工程] R815[医药卫生—基础医学]