Revolution 256 CT低剂量能谱碘水基物质对及三段能谱曲线斜率法定量鉴别不同周围型肺癌

Revolution 256CT low dose energy spectrum iodine water-based material pairs and the slope of three segments energy spectrum curve in quantitatively identifying different peripheral lung cancer types

目的 探讨Revolution 256 CT低剂量能谱扫描及三段能谱曲线斜率在不同周围型肺癌定量分析中的价值。方法 选取并分析126例行Revolution 256 CT低剂量能谱扫描并经病理证实的周围型肺癌患者,分别为腺癌62例、鳞癌49例及小细胞癌15例,测量并计算癌灶双期碘含量及水含量、标准化碘水浓度(NIC、NWC)及标准化碘水浓度之差(ICD、WCD)。重建双期能量衰减曲线,把衰减曲线分为三个区间40~70 KeV、70~100 KeV、100~140 KeV,分别计算斜率。用单因素方差分析比较多组间差异,组间有差异时采用LSD法进行两两比较,P<0.05为差异有统计学意义。结果 1)双期碘基值、NIC及ICD:腺癌>鳞癌>小细胞癌,差异有统计学意义(F=3.397~6.188,P<0.05);2)动脉期水基值、NWCAP:鳞癌>腺癌、鳞癌>小细胞癌,差异有统计学意义(F=5.017~9.899,P<0.05),腺癌与小细胞癌间比较差异无统计学意义。结节静脉期水基值、NWCVP及WCD比较差异无统计学意义(F=0.341~0.710,P>0.05);3)分段斜率比较显示40~70 KeV段:腺癌>鳞癌>小细胞癌;70~100 KeV段:鳞癌>腺癌>小细胞癌;100~140 KeV段:鳞癌>腺癌>小细胞癌;三组低能量水平差异大,高能量水平差异小。小细胞癌对应单能量下CT值最低。结论 Revolution 256 CT能谱定量参数指标有助于临床无创鉴别周围型肺癌。

Objective To investigate the value of low dose energy spectrum scanning and the slope of three spectral curves of Revolution 256 CT in quantitative analysis of different peripheral lung cancer.Methods A total of 126 cases of peripheral lung cancer,including adenocarcinoma in 62 cases,squamous cell carcinoma in 49 cases and small cell carcinoma in 15 cases confirmed by Revolution 256 CT low-dose energy spectrum scanning were retrospectively analyzed.The biphase iodine content and water content,standardized iodine water concentration(NIC,NWC)and the difference of standardized iodine water concentration(ICD,WCD)were measured and calculated.The two-phase energy decay curve was reconstructed,and the decay curve was divided into three intervals of 40~70 keV,70~100 keV and 100~140 keV,and the slope was calculated respectively.Oneway analysis of variance was used to compare the differences between multiple groups,and LSD method was used for pairwise comparison when there were differences between groups.P<0.05 meant the difference was statistically significant.Results 1)Biphasic iodine-base value,NIC and ICD were as follows:adenocarcinoma>squamous cell carcinoma>small cell carcinoma,and the differences were statistically significant(F=3.397~6.188,P<0.05).2)The arterial phase water base value and NWCAPwere as follows:squamous cell carcinoma>adenocarcinoma,squamous cell carcinoma>small cell carcinoma(F=5.017-9.899,P<0.05),with significant differences;but,there was no significant difference between adenocarcinoma and small cell carcinoma.There was no significant difference in water base value,NWCVP and WCD in venous phase of nodules(F=0.341~0.710,P>0.05).and 3)The slope comparison showed that the 40~70 keV segment was as follows:adenocarcinoma>squamous cell carcinoma>small cell carcinoma;For 70~100 keV segment,the result was squamous cell carcinoma>adenocarcinoma>small cell carcinoma;As for 100~140 keV segment,the result was squamous cell carcinoma>adenocarcinoma>small cell carcinoma;The low energy level of the three groups showed a large difference, while, the high energy level showed a small differ-ence. Small cell carcinoma corresponded to the lowest CT value at single energy. Conclusion Revolution CT spectral quantita-tive parameters are helpful for noninvasive diagnosis of peripheral lung cancer.