基于双能CT的影像临床联合模型鉴别门静脉良恶性栓子的价值

Value of combined model of clinical and imaging based on dual-energy CT for differentiating benign and malignant portal vein embolus

目的评估双能CT(dual-energy CT,DECT)定量参数联合临床实验室指标在鉴别门静脉癌栓(portal vein tumor thrombus,PVTT)和门静脉血栓(portal vein thrombosis,PVT)的价值。方法采用病例-对照研究设计方案,分析2022年5月至2024年3月在陆军特色医学中心放射科接受腹部双能CT增强检查并诊断有门静脉血栓或癌栓的65例患者的临床和影像资料,其中门静脉血栓患者39例,门静脉癌栓患者26例,记录患者年龄、性别,在后处理工作站重建线性融合图(linear blending,LB)、非线性融合图(non-linear blending,NLB)、40 keV及100 keV虚拟单能图(virtual monoenergetic image,VMI)、碘图(iodine concentration,IC)、电子云密度/有效原子系数图(electron density/effective atomic number,Rho/Zeff),在LB图像上评估栓子影像特征,包括附栓处血管壁是否光滑、附栓处血管有无增宽、栓子有无新生血管。比较血栓和癌栓在双能CT定量参数及临床实验室指标的差异,实验室指标有甲胎蛋白(alpha-feto protein,AFP)、癌胚抗原(carcinoembryonic antigen,CEA)、谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST),将双能CT定量参数、栓子影像特征及临床实验室指标进行单因素和多因素Logistic回归分析,再用ROC曲线评估双能CT定量参数及联合模型的诊断效能。结果双能CT各定量参数中,除Rho在血栓和癌栓之间差异无统计学意义外,其余参数在癌栓中均高于血栓,差异具有统计学意义(P<0.05)。多因素Logistic回归分析中,LB、NLB、CEA、AST的差异具有统计学意义(P<0.05),以NLB的诊断效能较好(AUC:0.830,敏感性:53.85%,特异性:100.00%,准确率:81.54%)。基于双能CT定量参数与临床实验室指标结合构建的联合模型(LB+NLB+CEA+AST)诊断效能最佳(AUC:0.983,敏感性:96.15%,特异性:92.31%,准确率:93.85%)。结论基于双能CT的影像临床联合模型对门静脉良恶性栓子的鉴别诊断提供了可靠依据,具有潜在应用前景。

Objective To investigate the value of dual-energy CT(DECT)quantitative parameters combined with clinical laboratory indicators in differentiation of portal vein tumor thrombus(PVTT)from thrombosis(PVT).Methods A case-control study was conducted on 65 patients diagnosed with portal vein thrombosis(n=39)or tumor embolus(n=26)who underwent abdominal dual-energy enhanced CT examination in our department from May 2022 to March 2024.Their clinical and imaging data were collected.Linear blending image(LB),non-linear blending image(NLB),40 keV and 100 keV virtual monoenergetic image(VMI),iodine image and electron density/effective atomic number image(Rho/Zeff)were reconstructed with the aid of post-processing workstation.The image characteristics of thrombus were evaluated in LB images,including whether the vessel wall at the thrombus was smooth,whether the vessel at the thrombus was widen,and whether the embolus was neovascularization.The quantitative parameters and clinical laboratory indicators of PVT and PVTT in DECT were compared.Laboratory indicators included apha-fetoprotein(AFP),carcinoembryonic antigen(CEA),alanine aminotransferase(ALT)and aspartate aminotransferase(AST).Univariate and multivariate logistic regression analyses were employed to analyze DECT quantitative parameters,embolus image characteristics and clinical laboratory indicators.Then receiver operating characteristic(ROC)curve was plotted to evaluate the diagnostic efficiency of the quantitative parameters and combined model of DECT.Results Among the DECT parameters,except for Rho,the other parameters in PVTT were significantly higher than those in PVT(P<0.05).Multivariate logistic regression analysis showed that there were obvious differences in LB,NLB,CEA and AST(P<0.05),and NLB had better diagnostic efficacy(AUC:0.830,sensitivity:53.85%,specificity:100.00%,accuracy:81.54%).The combined model based on DECT quantitative parameters and clinical laboratory indicators(LB+NLB+CEA+AST)obtained the best diagnostic efficacy(AUC:0.983,sensitivity:96.15%,specificity:92.31%,accuracy:93.85%).Conclusion The combined imaging and clinical model based on DECT provides a reliable reference for the differential diagnosis of benign and malignant portal vein embolus,and it has potential application prospects.