宝石能谱CT在非小细胞肺癌调强放疗中的应用价值

Application of CT Gemstone Spectral Imaging( GSI) in intensity modulated radiation therapy for non-small cell lung cancer

目的探讨宝石能谱CT在非小细胞肺癌调强放疗中的应用价值。方法经病理学或细胞学证实且行宝石能谱CT检查的非小细胞肺癌31例,放疗前普通模拟CT定位。比较普通模拟CT及宝石能谱CT肺原发灶大小、体积差异及纵隔淋巴结诊断的不同。结果普通模拟CT病灶直径平均为5.0 cm,宝石能谱CT直径为4.6cm(t=1.19,P=0.244);普通模拟CT病灶体积为63.5 cm3,宝石能谱CT病灶体积为50.4 cm3(t=22.049,P=0.000)。宝石能谱CT检出支气管壁增厚、管腔狭窄11例,普通模拟CT仅4例显示,且受侵长度及厚度均有差异。普通模拟CT诊断26枚淋巴结转移,宝石能谱CT诊断22枚淋巴结转移,4枚淋巴结考虑为反应性增生被排除转移。普通CT图像共5例有部分容积效应、伪影等,而宝石能谱CT各层面均显示了良好的空间分辨率和密度分辨率。宝石能谱CT使6例患者临床分期发生改变。结论宝石能谱CT在非小细胞肺癌原发灶确定、纵隔淋巴结诊断及调强放疗靶区勾画方面具有重要参考价值,对临床分期判定有指导、补充作用。

Objectlve To assess the application of high-definition CT （HDCT） Gemstone Spectral Imaging （GSI） in intensity- modulated radiation therapy （IMRT） for non-small cell lung cancer （NSCLC）. Methods Thirty one patients with pathologically or cytologically confirmed NSCLC were included in the study. All patients were examined with gemstone spectral HDCT and general simulation CT scan using the same position before radiotherapy. The size of primary loci, difference in volume and the diagnosis of mediastinal lymph nodes were compared between general simulation CT and gemstone spectral HDCT. Results The average diameter of lesion showed on general simulation CT was 5.0 cm, that on gemstone spectral HDCT was 4.6 cm （ t = 1.19,P = 0. 244）. The volume of lesion showed on general simulation CT was 63.5 cm3 and that on gemstone spectral HDCT was 50.4 cm3 （ t = 22. 049, P = 0. 000 ）. Gemstone spectral HDCT detected bronchial wall thickening,luminal stenosis in 11 cases, while general simulation CT detected only in 4 cases ; and there was difference in the detection of invaded length and thickness between two methods. General simulation CT detected 26 lymph nodes of metastasis,gemstone spectral HDCT detected 22 nodes of metastasis and the other 4 of reactive hyperplasia. General simulation CT images presented partial volume effect and artifacts in 5 case, and gemstone spectral HDCT showed a good spatial and density resolution. Clinical stage changes occurred in 6 patients based on gemstone spectral HDCT findings. Conclusion Gemstone spectral HDCT provides better clinical guidance than general simulation CT in intensity-modulated radiotherapy for NSCLC patients.