鼻咽癌表面引导放疗中2种参考表面的摆位准确性研究  

Setup accuracy of two reference surfaces in nasopharyngeal carcinoma surface-guided radiotherapy

作　　者：徐庚[1] 郑佳俊 孙丽[1] 丁乃昕 赵建[1] XU Geng;ZHENG Jia-jun;SUN Li;DING Nai-xin;ZHAO Jian(Jiangsu Cancer Hospital,the Affiliated Cancer Hospital of Nanjing Medical University,Jiangsu Institute of Cancer Research,Nanjing 210009,China;School of Biomedical Engineering and Informatics,Nanjing Medical University,Nanjing 211103,China)

机构地区：[1]江苏省肿瘤医院,南京医科大学附属肿瘤医院,江苏省肿瘤防治研究所,南京210009 [2]南京医科大学生物医学工程与信息学院,南京211103

出　　处：《医疗卫生装备》2023年第12期46-50,共5页Chinese Medical Equipment Journal

摘　　要：目的:比较鼻咽癌表面引导放疗(surface-guided radiation therapy,SGRT)中基于容积重建技术(volume rende-ring technique,VRT)参考表面和基于医学数字成像和通信(digital imaging and communications in medicine,DICOM)参考表面的摆位准确性。方法:选取2020年4—10月某院收治的20例采用塑形垫结合热塑网膜固定的鼻咽癌放疗患者。在首次锥形束CT(cone beam CT,CBCT)图像引导下完成治疗后,取下热塑网膜,基于光学表面监测系统(optical surface monitoring system,OSMS)获取患者的VRT参考表面,过程中嘱患者维持体位不变;DICOM参考表面则基于由患者的定位CT影像提取出的体表轮廓数据获得。在第5、10、15次放疗(CBCT图像引导)完成后,基于VRT和DICOM 2种参考表面分别测量患者6个维度的摆位误差。采用Python的Stats工具对基于2种参考表面测量的摆位误差分别进行维度相关性分析,以检查各个维度摆位误差之间的独立性。通过独立性检验后,对基于2种参考表面测量的每个维度的摆位误差数据进行Wilcoxon秩和检验。结果:基于2种参考表面测量的摆位误差在各个维度上相互独立,且基于VRT参考表面测量的6个维度上的摆位误差均小于基于DICOM参考表面测量的摆位误差。但基于2种参考表面测量的6个维度的摆位误差间的差异未随治疗进展而增大。结论:在采用塑形垫结合热塑网膜体位固定方式的鼻咽癌SGRT中,基于VRT参考表面的摆位准确性和一致性优于DICOM参考表面。Objective To compare the setup accuracies of the surface-guided radiation therapy for nasopharyngeal carcinoma based on volume rendering technique(VRT)reference surface and digital imaging and communications in medicine(DICOM)reference surface.Methods Twenty patients with nasopharyngeal carcinoma who received radiotherapy using the customized AccuCushion with a thermoplastic fixation mask were selected.After the first cone beam CT(CBCT)-based image-guided radiotherapy of each patient was completed,the thermoplastic mask was removed to obtain the VRT reference surface based on optical surface monitoring system(OSMS),during which the patient position was maintained through instructions;the DICOM reference surface was got based on the body surface contour data extracted from the patient's localized CT images.After the completion of the 5th,10th,and 15th CBCT image-guided radiotherapy treatments,the patients'6 dimensions of setup errors were measured based on the 2 reference surfaces,respectively.Dimensional correlation analyses were carried out on the setup errors measured based on the 2 reference surfaces separately using Python's Stats tool to test the independence between the setup errors in each dimension.After independence test,Wilcoxon rank sum test was performed on the data of the setup errors based on each dimension measured with the 2 reference surfaces.Results The two sets of setup errors were independent of each other in all dimensions.The errors based on VRT reference surface were lower than those based on DICOM reference surface in 6 dimensions,while the difference between the 6-D errors of the two groups did not gradually become significant as the treatment progressed.Conclusion In the SGRT of nasopharyngeal carcinoma using a customized cushion combined with a thermoplastic mask,the setup accuracy and consistency based on VRT reference surface are both higher than those based on DICOM reference surface.

关 键 词：鼻咽癌放疗 表面引导放疗 光学表面监测系统 参考表面 VRT DICOM 摆位准确性 

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