规范化多层螺旋CT门静脉成像诊断小型猪肝纤维化的实验研究

Diameter of portal venous system measured on computed tomography portography standardized by dynamic contrast-enhanced scans in a piglet model:association with stage of liver fibrosis

目的探讨规范化多层螺旋CT门静脉成像对实验小型猪肝纤维化的诊断价值。方法使用健康中国小型猪16只,采用四氯化碳(CCl4)制造肝纤维化各期模型。实验动物从第0周(正常实验动物)至建模后第5、9、16、21周分别接受CT动态增强扫描,获得门静脉强化达到峰值时间(TTP),以此确定门静脉最佳成像时间,并以此作为门静脉成像延迟时间行门静脉成像扫描,最后测量门静脉主干管径(PVD)、肠系膜上静脉管径(SMVD)、脾静脉管径(SVD),统计分析上述参数在疾病发展过程中的变化规律及其对实验性肝纤维化的诊断价值。结果 (1)在肝纤维化的进展过程中,TTP逐渐延长(r=0.234,p<0.05),SVD、PVD与SMVD逐渐增大(r=0.272-0.613,p<0.05);Mann-Whitney检验结果显示,SVD在肝纤维化0期与1-4期间差异具有统计学意义;SVD与PVD在肝纤维化S0-1vs.S2-4、S0-2vs.S3-4、S0-3vs.S4差异均具有统计学意义(各p<0.01)。SMVD在任何两期间对比差异不具有统计学意义(各p>0.05)。(2)在诊断肝纤维化ROC曲线中,SVD在诊断肝纤维化≥S1中具有意义(曲线下面积[AUC]=0.893);PVD和SVD均对诊断≥S2,≥S3以及S4有意义(AUC=0.789-0.829),其中SVD诊断效能大于PVD。结论应用规范化多层螺旋CT门静脉成像技术测得的SVD,对诊断肝纤维化具有重要价值。

Objective To explore the value of standardized multislice spiral CT portography for the liver fibrosis in piglets. Methods 16 Chinese healthy miniature piglets were prospectively used to make liver fibrosis models by carbon tetrachloride. On 0, 5th, 9th, 16th and 21st week after the beginning of modeling, all normal laboratory animals were treated with CT dynamic contrast-enhanced scans, respectively. Time to peak-enhancement （TTP） obtained from dynam- ic scan was used as standard scan time to perform CTP. Spleen vein diameter （SVD）, portal vein diameter （PVD） and superior mesenterie vein diameter （SMVD） were measured on CTP. Results TTP, SVD, PVD and SMVD increased with the progress of liver fibrosis （r=0. 234 to 0. 613, all p〈0.05）. Mann-Whitney tests demonstrated that SVD could classify liver fibrosis between stage 0 and 1-4. Both SVD and PVD could discriminate liver fibrosis between stage 0-1 and 2-4, between stage 0-2 and a-4, and between stage 0-3 and 4 （all p〈0.01）. SMVD could not differentiate between any two stages （all p〉0.05）. Receiver operating characteristic analysis （ROC） illustrated that SVD could classify the stage ≥1 （area under curve [AUC]=0. 893）. AUC of SVD was larger than that of PVD for classifying stage ≥2, ≥3 and 4 （AUC=0. 789 to 0. 829）. Conclusion Diameter of portal system could stage liver fibrosis, and SVD can be best used to classify this disease.