摘要目的 探讨在4D-CBCT扫描后,人工图像配准与灰度T+R图像配准在NSCLC(NSCLC) SBRT中的临床应用,得到在NSCLC-SBRT疗程中最适合的配准方式.方法 10例接受SBRT的NSCLC患者,在分次4D-CBCT扫描后,对扫描图像与定位CT图像分别进行人工与灰度T+R配准.在患者分次治疗过程中,对配准图像分别计算最大互信息、Haunsdorff距离、平均对称距离,并行配对t检验差异.结果 第1～3次SBRT时,灰度T+R配准较人工配准的最大互信息平均提高8.8％ (P=0.003,0.000,0.008),Haunsdorff距离平均减少21.1％(P=0.000,0.000,0.000),平均对称距离平均较少13.4％(P=0.000,0.002,0.018);第6～8次SBRT时,人工配准较灰度T+R配准的最大互信息平均提高19.3％ (P=0.014,0.000,0.000),Haunsdorff距离平均减少17.6％ (P=0.000,0.000,0.000),平均对称距离平均较少19.6％(P=0.001,0.000,0.000).结论 在NSCLC患者治疗前期,4D-CBCT后应用灰度T+R进行图像配准较为合理,治疗后期应用人工配准较为合理.

abstractsObjective To investigate the artificial and gray T+R 4D-CBCT image registration for non-small cell lung cancer (NSCLC) with SBRT.Methods 2D SBRT 10 patients with NSCLC,their 4D-CBCT scan images and reference CT images were registered by the methods of artificial and gray T + R registration.The maximum mutual information (MI),Haunsdorff distance and average symmetry distance (ASD) were calculated and were analyzed by paired-t test.Results In 1-3 fraction SBRT,the maximum MI for Gray T+R registration was averaged improved 8.8％ (P =0.003,0.000,0.008),Haunsdorff distance and ASD were averaged reduced 21.1％ (P=0.000,0.000,0.000) and 13.4％ (P=0.000,0.002,0.018) respectively,and they all had the statistical significance compared with artificial registration in the early period of treatment;in 6-8 fraction SBRT,compared with gray T+R registration the maximum MI for artificial registration was averaged improved 19.3％ (P =0.014,0.000,0.000),Haunsdorff distance and ASD were averaged reduced 17.6％ (P =0.000,0.000,0.000) and 19.6％ (P =0.001,0.000,0.000) respectively,and they also had the statistical significance.Conclusions Gray T+R image registration was reasonable in early period of treatment and artificial image registration was available in later period of treatment.