光学表面监测系统引导放射治疗对提高四肢肿瘤位置准确性和减小靶区外放的有效性研究  

Study on the effectiveness of OSMS-guided radiotherapy in improving the accuracy of tumor location of limbs and reducing the effectiveness of external expansion of target region

作　　者：郇福奎 冯鑫 芦凤玉 李朝辉 魏国友 李伟 李洪菊 张彦新 HUAN Fu-kui;FENG Xin;LUFeng-yu(Department of Radiation Oncology, National Cancer Center/National Clinical ResearchCenter for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing100021, China;不详)

机构地区：[1]国家癌症中心国家肿瘤临床医学研究中心中国医学科学院北京协和医学院肿瘤医院放疗科,北京100021

出　　处：《中国医学装备》2022年第6期10-14,共5页China Medical Equipment

摘　　要：目的:分析基于光学表面监测系统(OSMS)和基于激光定位灯系统摆位的四肢肿瘤患者椎形束CT(CBCT)图像,研究OSMS减小四肢肿瘤摆位误差的有效性。方法:选取在医院进行放射治疗的24例四肢肿瘤患者,按摆位方法的不同将其分为观察组和对照组,每组12例。观察组应用OSMS协助放射治疗摆位;对照组应用常规的激光灯系统进行放射治疗摆位。分别统计两组患者在左右(x)、头脚(y)及前后(z)3个方向的平移误差和矢状面(Rx)、横断面(Ry)及冠状面(Rz)3个平面的旋转误差,计算其系统误差个体病例误差平均值的标准差(Σ)和随机误差个体病例误差标准差的均方根(σ),以及摆位误差的分布情况。用公式2.5Σ+0.7σ计算临床靶区体积(CTV)至计划靶区体积(PTV)(CTV-PTV)的外放边界。结果:观察组和对照组x、y及z的3个方向平移误差分别为(1.14±1.43)mm和(2.52±3.08)mm、(1.38±1.88)mm和(2.26±2.51)mm及(1.26±1.76)mm和(4.80±3.41)mm;观察组和对照组在Rx、Ry及Rz的3个平面旋转误差分别为(0.71±0.69)°和(0.82±1.12)°、(1.11±1.53)°和(1.49±1.14)°及(0.89±0.82)°和(0.52±1.18);两组平移误差在z方向和横断面旋转误差在Ry平面的比较,差异有统计学意义(Z=-3.623,Z=-2.501;P<0.05)。观察组和对照组在x、y、z的3个方向上的CTV-PTV靶区外放边界分别为3.9 mm、4.8 mm、4.4 mm和8.5 mm、7.4 mm、14.4 mm。观察组CTV-PTV靶区外放边界在x、y和z方向分别减小为对照组的45.9%、64.8%和59.0%。结论:应用OSMS协助四肢的放射治疗摆位能够提高四肢肿瘤放射治疗的位置准确性,尤其是可减小z方向的平移误差和横断面的旋转误差,并能够有效的减小四肢肿瘤的靶区外放范围。Objective: To analyze the cone beam computed tomography(CBCT) images of patients with limbs tumor on the bases of optical surface monitoring system(OSMS) and laser location lamp system, so as to research the effectiveness that OSMS reduced the position error of limbs tumor. Methods: 24 patients with limbs tumor who received radiotherapy in hospital were selected, and they were divided into observation group and control group according to different positioning methods, with 12 cases in each group. Observation group adopted OSMS to assist position of radiotherapy, while control group adopted routine laser lamp system to conduct position of radiotherapy. The translation errors of three directions included left and right(x), head and foot(y) and front and back(z), and the rotation errors of three planes included vertical plane(Rx), transverse section(Ry) and coronal plane(Rz) of two groups were calculated respectively as statistical method.And the standard deviation(Σ) of the means of personal case errors of systematic error, and the root-mean-square(σ) of standard deviation of personal case errors of random error, and the distribution of position error were further calculated. The formula(2.5 Σ+0.7σ) was used to calculate the margin of external expansion from clinical target volume(CTV) to planned target volume(PTV). Results: The translation errors of 3 directions(x, y and z) of observation group and control group were [(1.14±1.43) mm,(2.52±3.08) mm and(1.38±1.88)mm] and [(2.26±2.51)mm,(1.26±1.76)mm and(4.80±3.41)mm], respectively. The rotation errors of 3 planes(Rx, Ry and Rz) of observation group and control group were [(0.71±0.69)°,(0.82±1.12)° and 1.11±1.53)°] and [(1.49±1.14)°,(0.89±0.82)° and(0.52±1.18)°], respectively. The differences of z direction of translation error and Ry plane of rotation error of transverse section between two groups were significant(Z=-3.623, Z=-2.501, P<0.05), respectively. The margin of external expansion of CTV-PTV target region on 3 directions(x, y and z) of

关 键 词：光学表面监测系统(OSMS) 四肢肿瘤放射治疗 靶区外放 摆位误差 椎形束CT(CBCT) 

分 类 号：R815.2[医药卫生—放射医学]