射波刀Xsight患者六维方向数据分析

目的:分析30例Xsight追踪方式的患者治疗过程中所有曝光点生成的六维方向数据。方法:随机选择30例Xsight追踪方式的患者,在真空垫固定、CT-SIM定位,使用G3射波刀进行治疗,共采集1 358个曝光点图像,得到1 358组需要机械臂校准六维方向数据,其中包括患者移动超出射波刀机械臂校准范围的337个曝光点的数据,进行各个方向的平均值、标准差的比较。结果:在患者6个方向上的左右平移LET(+)/RIG(-)、前后平移ANT(+)/POS(-)、头脚平移NIF(+)/SUP(-)、左右旋转R(+)/L(-)、头高低Head-up(+)/Head-up(-)、逆顺时针CCW(+)/CW(-)上的最大值为2.3 mm、2.0 mm、1.7 mm、2.5°、1.6°、2.1°,最小值为-2.8 mm、-2.1 mm、-1.2 mm、-2.1°、-1.3°、-1.5°,中位值为-0.4 mm、0.3 mm、0.1 mm、0.6°、0.2°、0.4°,变化范围为5.1 mm、4.1 mm、2.9 mm、4.6°、2.9°、3.6°。结论:在射波刀立体定向精确放疗中,患者本身的运动呈现出对称运动,幅度相当,中位值接近于0,但是患者本身的运动变化范围超出了射波刀Xsight系统所要求的总误差不超过0.95 mm的要求,尤其是左右平移LET(+)/RIG(-)及左右旋转R(+)/L(-)(°),这充分说明了射波刀系统在出射束前进行机械臂校准的必要性和重要性。

Six-dimensional Orientation Data Analysis of Patients Tracked by Cyber Knife Xsight

Objective To analyse all the six-dimensional orientation data generated from all the exposure points of 30 cases patients tracked by Cyber Knife Xsight.Methods Thirty cases tracked by Cyber Knife Xsight were selected randomly,fixed on CT-SIM location,and were treated by G3 Cyber Knife.A total of 1358 exposure point images were collected,from which 1358 teams of six-dimensional orientation data that needed to be calibrated by the robot arm were gotten,including the images of 337 exposure points when the patients were out of the calibrated range of Cyber Knife robot arm.The means and standard deviations of all the directions were compared.Results The six-dimensional orientations were including left and right translation LET(+) / RIG(-),forward and backward translation ANT(+) / POS(-),head and feet translation NIF(+) / SUP(-),left and right rotation R(+) / L(-)(degree),Head-up(+) / Head-up(-)(degree),and anticlockwise and clockwise CCW(+) / CW(-),the maximum value of which was 2.3,2.0,1.7,2.5,1.6 and 2.1,the minimum one was-2.8,-2.1,-1.2,-2.1,-1.3,and-1.5,the median was-0.4,0.3,0.1,0.6,0.2 and 0.4,and the changes range was 5.1,4.1,2.9,4.6,2.9 and 3.6,respectively.Conclusion The patients’ movement during the Cyber Knife precision radiation therapy shows a symmetrical characteristic with close amplitude and a median value closed to 0.But the movement range of patients themselves is beyond the requirements that the total error should not be more than 0.95 mm required by Cyber Knife Xsight system,especially the left and right translation LET(+) / RIG(-) and left and right rotation R(+) / L(-)(degree),which fully explains the necessity and importance of the calibration by the robot arm before the beam.