CT双能量成像在诊断肺结节不同病变中的诊断价值

Value of dual energy CT imaging in the diagnosis of different lesions of pulmonary nodules

目的探讨CT双能量成像在肺内非小细胞肺癌、结核、炎性结节等不同肺结节病变中的诊断价值。方法前瞻性收集2017年12月至2020年10月温州市人民医院经常规体检或CT检查收治的疑似肺内实性结节患者95例,根据病理结果将其分为非小细胞肺癌组(n=42)、结核组(n=33)、炎性结节组(n=20),所有患者均行CT双能量平扫及双期增强扫描,评估患者CT影像形态学特征(血管受累、病灶钙化、淋巴结增大、结节边缘、部位、强化特点),同时测量比较CT双能量成像相关定量参数[动脉期标准化碘浓度(normalized iodine concentration of arterial phase,NICAP)及静脉期标准化碘浓度(normalized iodine concentration of venous phase,NICVP)、能谱曲线斜率(K40~100keV)]。分析比较三组肺结节病变间CT双能量成像相关定量参数的差异。评价CT影像特征、CT双能量成像相关定量参数兼备诊断肺实性结节的效能。采用受试者操作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under the curve,AUC)评价非小细胞肺癌、结核、炎症的敏感度及特异性等诊断效能指标。结果三组肺结节病变的血管受累、病灶钙化、淋巴结增大、结节边缘、部位、强化特点等CT征象比较,差异均具有统计学意义(P<0.05)。非小细胞肺癌组结节多呈血管受累、淋巴结增大、结节边缘呈毛刺/分叶状、发病于两肺下叶、强化不均匀;结核组结节多呈病灶钙化、结节边缘不光整,发病于两肺上叶、强化不均匀;炎性结节组结节多呈边缘不光整、发病于两肺下叶、强化均匀。三组肺结节病变的NICAP、NICVP、K_(40~100keVap).、K_(40~100keVvp)比较,差异具有统计学意义(P<0.05),均呈炎性结节组>非小细胞肺癌组>结核组的顺序降低,差异均具有统计学意义(P<0.05)。NICAP、NICVP、K_(40~100keVap).、K_(40~100keVvp).均可用于鉴别诊断炎性和非小细胞肺癌、非小细胞肺癌和结核(P<0.05)。NICAP+NICVP+K_(40~100keVap).+K_(40~100keVvp).评价炎症和非小细胞肺癌、非小细胞肺癌和结核的ROC曲线AUC、敏感度及特异性等诊断效能指标均较高。结论CT可清晰地描述非小细胞肺癌、结核及炎症的形态学特征,但三种肺结节病变在形态学特征存在重叠,因此鉴别诊断的价值有限。CT双能量成像定量参数分析为非小细胞肺癌、结核及炎性结节的鉴别诊断提供了全新的思路,可提高临床诊断效能,值得推广应用。

Objective To investigate the diagnosis value of dual energy CT imaging in the pulmonary nodule lesions such as non-small cell lung cancer,tuberculosis,and inflammation in the lung.Methods A total of 95 patients with suspected solid nodules in the lung admitted to Wenzhou People's Hospital by routine physical examination or CT examination from December 2017 to October 2020 were collected,prospectively.According to the pathological results,the patients were divided into the non-small cell lung cancer group(42 cases),tuberculosis group(33 cases)and inflammation group(20 cases).All patients underwent dual energy CT plain scan and dual-phase enhanced scan to evaluate the CT image morphological features(vascular involvement,calcification,lymph node enlargement,nodule edge,location,enhancement characteristics).The quantitative parameters[normalized iodine concentration of arterial phase(NICAP),normalized iodine concentration of venous phase(NICVP),energy spectrum curve slope(K40-100keV)]of three groups were recorded and compared.The diagnosis value of the CT image features and quantitative parameters of dual energy CT imaging in the different solid nodules of lung were analyzed.Receiver operating characteristic(ROC)curve and area under the curve(AUC)were used to evaluate the sensitivity and specificity of non-small cell lung cancer,tuberculosis,inflammation and other diagnostic efficacy indicators.Results There were significant differences in CT signs such as vascular involvement,lesion calcification,lymph node enlargement,nodule edge,location and enhancement characteristics in three groups(P<0.05).In the non-small cell lung cancer group,the nodules were mostly vascular involvement,enlarged lymph nodes,spiculated/lobulated nodule edges,onset in the lower lobes of both lungs and uneven enhancement.In the inflammatory group,the nodules were mostly irregular in margins,occurred in the lower lobes of two lungs,and had uniform enhancement.There were significant differences in NICAP,NICVP,K_(40-100keVap).and K_(40-100keVvp).of nodules in three groups(P<0.05),which were all in the order of inflammatory group>non-small cell lung cancer group>tuberculosis group(P<0.05).NICAP,NICVP,K_(40-100keVap).and K_(40-100keVvp).can be used for the differential diagnosis of inflammation,non-small cell lung cancer and tuberculosis(P<0.05).The diagnostic efficacy indicators such as AUC,sensitivity and specificity of tuberculosis of the NICAP+NICVP+K_(40-100keVap).+K_(40-100keVvp).in differential diagnosis of inflammation,non-small cell lung cancer,and tuberculosis were all high.Conclusion CT imaging can clearly describe the morphological features of non-small cell lung cancer,tuberculosis and inflammatory nodules,but the morphological features of three different kinds of nodules are overlap,so the value of differential diagnosis is limited.Analysis of quantitative parameters of dual energy CT imaging can provide a new idea for the diagnosis of non-small cell lung cancer,tuberculosis and inflammatory nodules,which can improve the clinical diagnostic efficiency and is worthy of wide application.