能谱CT评估肝硬化食管静脉曲张程度的价值研究

Studies of the Application of Spectral CT Evaluating the Grading of Esophageal Varices of Liver Cirrhosis

目的通过能谱CT碘基值与胃镜下食管静脉曲张(EV)程度进行比较,探讨能谱CT碘基值能否评估EV程度及出血风险,为临床治疗提供重要参考价值。方法 42例肝硬化患者分别进行能谱CT扫描及胃镜检查,分别记录动脉期、静脉期肝左叶、肝右叶、尾状叶、腹主动脉、门静脉、胃左静脉碘基值及胃镜下EV程度。胃镜下无、轻度EV为曲张非严重组,中、重度EV为曲张严重组。比较肝硬化组不同肝功能分级之间及胃镜下EV不同组别之间动/静脉期标准化碘浓度(A/VNIC)、胃左静脉指数(LGI)差异。绘制ROC曲线。结果肝硬化Child-C级的ANIC较Child-A、B级高,分别为(0.09±0.04)、(0.05±0.02)。胃镜下EV严重组较非严重组VNIC低,分别为(0.36±0.04)、(0.42±0.07);LGI高,分别为(1.04±0.16)、(0.76±0.31)。胃镜下严重胃底静脉曲张(GV)组较非严重曲张组LGI高,分别为(1.04±0.10)、(0.89±0.29)。出血组较未出血组VNIC低,分别为(0.36±0.04)、(0.42±0.08);LGI高,分别为(1.02±0.17)、(0.76±0.32)。LGI临界值为0.86时,ROC曲线下面积为0.84,诊断严重EV敏感性为92%,特异性为80%。LGI临界值为0.95时,ROC曲线下面积为0.73,诊断严重GV敏感性为92%,特异性为62%。结论能谱CT胃左静脉指数可以用来评估EV程度及出血风险,进而减少频繁地胃镜随访,为临床治疗提供重要的参考价值。

Objective To study the relationship between Iodine concentrations obtained by Spectral CT and the grading of esophageal varices( EV) via endoscopy and to evaluate whether these Spectral parameters might predict the grading of EV and the risk of variceal bleeding. Methods 42 patients with cirrhosis were prospectively enrolled in this study. They all underwent three-phases Spectral CT and endoscopic scanning. Spectral parameters as Normalized Iodine concentration( NIC) 、Left gastric vein index( LGI) were obtained by Spectral CT. The relationship between Spectral parameters and grading of EV evaluated by endoscopy were compared. ROC curve was drawn. The differences of Spectral parameters between different Child-Class were also compared. Results Patients with Child-C had a higher ANIC during AP than those in Child-A,B. There were significant differences in NIC during PVP and LGI value between patients with severe EV and those with no or non-severe EV determined by endoscopy,with those experienced bleeding episode and those without. Patients with large gastric varices have higher LGI than those with small one. The cut-off value of the LGI was 0. 86 for sever EV. The area under ROC curve was 0. 84. The sensitivity and specificity was 92%,80%. The cut-off value of the LGI was0. 95 for sever gastric varices GV. The area under ROC curve was 0. 73. The sensitivity and specificity was 92%,62%.Conclusion LGI obtained by Spectral CT could be a non-invasive method to evaluate the grading of EV and the risk of variceal bleeding so as to avoid repeated endoscopic monitor.