能谱CT在鉴别中央型肺癌与阻塞性肺不张中的价值研究

DUAL ENERGY CT DIFFERENTIATION CENTRAL LUNG CANCER AND PULMONARY ATELECTASIS

目的探讨能谱CT对中央型肺癌与阻塞性肺不张的鉴别能力。方法收集经病理证实为中央型肺癌且伴有肺不张的患者60例,进行能谱增强CT扫描,获得肺动脉期与支气管动脉期的常规图像和不同keV下的单能量图像,比较常规图像与单能量图像对肺癌和肺不张边界的检出率;测量肿瘤和不张肺组织的碘含量,分析碘含量的差异。结果肺动脉期和支气管动脉期单能量图像显示肿瘤与肺不张界限效果较好(检出率分别为81.67%、91.67%),检出率均高于常规混合能量图像检出率(65.00%、73.33%),差异均有统计学意义(均P<0.05)。肺动脉期和支气管动脉期肺癌组织碘含量分别为(12.78±4.53)μg/cm^(3)和(16.06±5.43)μg/cm^(3),均低于不张肺组织碘含量(28.82±12.13)μg/cm^(3)和(25.25±6.29)μg/cm^(3),差异均有统计学意义(均P<0.05)。肺动脉期界值为22.01μg/cm^(3)时灵敏度和特异度较高,支气管动脉期界值为19.223μg/cm时灵敏度和特异度较高。结论能谱CT对中央型肺癌与阻塞性肺不张有较高的鉴别能力,对指导临床尤其是放疗精确定位有一定帮助。

Objective To evaluate the ability of dual energy CT in differentiating central lung cancer from pulmonary atelectasis.Methods Sixty cases of central cancer with atelectasis were inspected with dual energy CT.The detection rates of lung cancer and atelectasis were compared between conventional image and single-energy image.The iodobase values of tumor and atelectatic lung tissues were measured.Results Single-energy images of pulmonary artery and bronchial artery showed a good borderline between tumor and atelectasis(detection rate 81.67%、91.67%).The detection rate was higher than that of the conventional mixed energy image(65.00%、73.33%),the difference was statistically significant.The Iodine Content(12.78±4.53) μg/cm^(3),(16.06±5.43) μg/cm^(3) of lung cancer tissue in pulmonary artery stage and bronchial artery stage was significantly lower than that in atelectasis(28.82±12.13) μg/cm^(3),(25.25±6.29) μg/cm^(3).The sensitivity and specificity were higher when the pulmonary arterial phase cutoff value was 22.01 μg/cm^(3),and the sensitivity and specificity were higher when the bronchial artery phase cutoff value was 19.22 μg/cm^(3).Conclusion Dual energy CT is helpful to improve subjective diagnosis of lung cancer with atelectasis, and it is helpful to guide the precise location of clinical, especially radiotherapy.