锥形束CT图像引导乳腺癌放疗中不同配准方法研究  

Comparison of different registration methods in cone beam CT image guided radiotherapy for breast cancer

作　　者：刘姝言 高兴旺 刘懿梅 周杨 邓小武[1] 陈仲本[5] 彭应林 LIU Shuyan;GAO Xingwang;LIU Yimei;ZHOU Yang;DENG Xiaowu;CHEN Zhongben;PENG Yinglin(Department of Radiation Oncology,Sun Yat-sen University Cancer Center/State Key Laboratory of Oncology in Southern China/Collaborative Innovation Center for Cancer Medicine,Guangzhou 510060,China;The First Affiliated Hospital,Sun Yat-sen University,Guangzhou 510062,China;Shenzhen Hospital,National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital of Chinese Academy of Medical Sciences and Peking Union Medical College,Shenzhen 518116,China;Zhuzhou Hospital Affiliated to Xiangya School of Medicine,Central South University,Zhuzhou 412000,China;Xinhua College of Sun Yat�sen University,Guangzhou 510520,China)

机构地区：[1]中山大学肿瘤防治中心/华南肿瘤学国家实验室/肿瘤医学协同创新中心,广东广州510060 [2]中山大学附属第一医院,广东广州510062 [3]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深圳医院,广东深圳518116 [4]中南大学湘雅医学院附属株洲医院,湖南株洲412000 [5]中山大学新华学院,广东广州510520

出　　处：《中国医学物理学杂志》2023年第1期7-12,共6页Chinese Journal of Medical Physics

基　　金：国家自然科学基金(12005316);中华国际医学交流基金会肿瘤精准放疗星火计划(2019-N-11-20);广州市科技计划项目(202206010154,202206010180);广州新华学院大学生创新创业训练项目(202113902007)。

摘　　要：目的:比较锥形束CT(CBCT)图像引导乳腺癌放疗中采用不同配准方法[3D配准(平移)和6D配准(平移+旋转)]对配准精度的影响,为选择合理的图像引导方法提供临床依据。方法:回顾性分析18例乳腺癌患者共101次治疗前摆位CBCT图像,将CBCT图像与计划CT图像分别采用3D灰度配准和6D灰度配准方法进行配准,比较和分析两种配准方法的3D平移方向的配准偏差差异并计算其平移差别,进一步统计分析旋转角度偏差与平移差别的相关性并做线性模拟。结果:3D和6D两种配准方法得到不同的平移配准结果,其中在头脚(Y)方向[(-1.47±3.00)mm vs(-0.87±3.27)mm]和前后(Z)方向[(-2.91±4.49)mm vs(-3.41±5.38)mm]的差异存在统计学意义(P<0.001)。旋转角度偏差与平移差别存在相关性,其中ΔX和ΔZ均与Ry呈线性强相关性,其相关系数PCC分别为-0.883和0.795(P<0.001);ΔY与Rx呈线性强负相关性,PCC=-0.722(P<0.001)。根据线性模拟公式计算,当Rx>1°且Ry>2°时,两种配准方法将在各平移方向上存在将近1 mm的平移差别。结论:3D和6D平移配准结果的差异具有统计学意义。6D配准的旋转角度大小影响平移差别的大小,其中Ry影响最大。建议使用6D配准方法时应使用六维床进行6D偏差修正,以减小平移差别的影响。Objective To compare the effects of three-dimensional(3D)registration(translation only)and six-dimensional(6D)registration(translation+rotation)on registration accuracy in cone beam CT(CBCT)image guided radiotherapy for breast cancer for providing clinical basis for selecting the optimal image guidance method.Methods The positioning CBCT images before 101 treatments in 18 patients with breast cancer were retrospectively analyzed.The CBCT images and planned CT images were registered by 3D grey-scale image registration and 6D grey-scale image registration,separately.The registration deviation differences in the 3D translation directions of the two registration methods were compared and analyzed;and the translation difference(Δ)was calculated.Furthermore,the correlation between rotation angle deviation(R)and translation difference(Δ)was statistically analyzed,and a linear simulation was carried out.Results 3D and 6D registration methods had different translation registration results,in which there were statistical differences in superior-inferior(Y)direction and anterior-posterior(Z)directions[(-1.47±3.00)mm vs(-0.87±3.27)mm,(-2.91±4.49)mm vs(-3.41±5.38)mm;P<0.001].The rotation angle deviation(R)was correlated with the translation difference(Δ).ΔX andΔZ had strong linear correlations with Ry(PCC=-0.883,0.795;P<0.001),and there was a strong linear negative correlation betweenΔY and Rx(PCC=-0.722,P<0.001).According to the linear simulation formula,when Rx was greater than 1°and Ry was greater than 2°,there was nearly 1 mm translation difference between the two registration methods in each translation direction.Conclusion The 3D translation registration results significantly differ from 6D translation registration results.The rotation angle of 6D registration affects the translation difference,among which Ry has the greatest impact.It is suggested that when using 6D registration method,6D couch should be used to correct 6D deviations in order to reduce the effects of translation difference.

关 键 词：乳腺癌 图像引导放射治疗 锥形束CT 摆位误差 图像配准 六维床 

分 类 号：R318[医药卫生—生物医学工程] R811.1[医药卫生—基础医学]