摘要
目的比较四维CT（4DCT）与自主呼吸控制（ABC）辅助三维CT（3DCT）确定的周围型肺癌大体肿瘤体积（GTV）的位置、位移及相互包含度和匹配指数。方法18例周围型肺癌患者依次完成胸部4DCT扫描及ABC辅助平静吸气末屏气（EIH）和呼气末屏气（EEH）3DCT扫描。每个呼吸周期的4DCT图像平均分为10个呼吸时相，0时相为吸气末时相（CTo），50时相为呼气末时相（ck），分别在CT0、CT50、CTEIH和CTEEH上勾画GTV，得到GTV0、GTV50、GTVEIH和GTVEEH。结果全组患者GTV0与GTVEIH、GTV50与GTVEEH中心点间距分别为3．9和3．4mm，上叶组患者分别为3．2和3．1mm，下叶组患者分别为5．0和4．7mm。上叶组患者CTV0与GTVEIH体积相互包含度为65．9％和63．1％，GTV50与GTVⅢ体积相互包含度为67．5％和63．1％；下叶组患者GTV0与GTVⅢ体积相互包含度为35．3％和21．4％，GIN50与GTV EEH体积相互包含度为27．8％和24．8％。上叶组患者GTV0与GTVEIH、GTV50与GTV。体积匹配指数分别为0．5和0．6，下叶组分别为0．2和0．3。在三维方向上，无论上叶组还是下叶组，GIN。和GTVEEH中心点的位移（ABC位移）与GTV0和GTV50中心点的位移（4D位移）的差异均〈1mm。结论基于ABC辅助3DCT扫描测得的平静吸气末屏气和呼气末屏气间肿瘤的位移，可以代替4DCT极限时相测得的肿瘤位移用于内靶区的构建。但ABC辅助3DCT扫描平静吸气末和呼气末图像获取的GTV，与4DCT扫描得到的极限时相图像获取的GTV存在明显的空间错位，尤其是体积较小且运动幅度较大的肿瘤。
Objective To compare the position, displacement, degree of inclusion （DI） and matching index （MI） of the gross tumor volume （GTV） for peripheral lung cancer based on 4-dimensional CT （4D CT） and 3-dimensional CT （3D CT） assisted with active breathing control （ABC）. Methods Eighteen patients with peripheral lung cancer underwent 4D CT simulation scan during free breathing and 3D CT simulation scans in end-inspiratory hold （ CTEIH ） and end-expiratory hold （ CTEEn ） in turn. The 4D CT images from each respiratory cycle were sorted into 10 phases, phase 0 was defined as end-inspiratory phase （ CT0 ）, and phase 50 was defined as end-expiratory phase （ CT50）. The GTVs were delineated separately on CTo, CT5o, CTEIH and CTEEu images, and then GTVo, GTV50, GTVEm and GTVEEIt were constructed, respectively. Results The median distances between the centroids of GTV0 and GTVEm, GTVso and GTVEEs were 3.9 mm and 3.4 mm in all patients, 3.2 mm and 3.1 mm in the upper lobe group, and 5.0 mm and 4.7 mm in the lower lobe group, respectively. In the upper lobe group, the GTVo and GTVEIn were 65.9% and 63.1% , and the median mutual Dis of GTVso and GTVEEa were 67.5% , 63.1% , respectively. In the lower lobe group, the GTVo and GTVEIn were 35.3% and 21.4%, and the median mutual Dis of GTVs0 and GTVEE＂ were 27.8% and 24.8%, respectively. In the upper lobe group, the median MI of GTV0 and GTVEIn was 0.5, and the median MI of GTV50 and GTVEEn was 0. 6. In the lower lobe group, the median MI of GTV0 and GTVEm was 0.2, and the median MI of GTV50 and GTVEEH was 0.3. Whether in the upper or lower lobe groups, all the differences between displacements of centroid positions of GTVEm and GTVEEH （ABC displacement） and GTV0 and GTV50 （4D displacement ） were 〈 1 mm in three dimensional directions （ all P 〉 0.05 ）. Conclusions The target displacement of tumors based on 3D CT scanning in end-inspiratory hold and end-expiration hold can be used to construct internal target volume instead of that based on 4D CT scanning in extreme phase for peripheral lung cancers, but spatital mismatches of GTVs are obvious between extreme phases in 4D CT and corresponding phases in 3D CT assisted with ABC, especially for tumors of smaller volume and with larger motion amplitude.
出处
《中华肿瘤杂志》
CAS
CSCD
北大核心
2013年第7期514-517,共4页
Chinese Journal of Oncology
基金
山东省自然科学基金（ZR2011HM004）
山东省科技发展计划（2012GSFll839）
关键词
肺肿瘤
计算机体层摄成像
三维
成像
四维
自主呼吸控制
靶区位移
Lung neoplasms
Computed tomography
Imaging, three-dimensional
Imaging, four-dimensional
Active breathing control
Target displacement
