应用ROC曲线评价超声造影对肝纤维化的诊断价值

目的:应用活体大鼠肝纤维化模型,观察超声造影在不同肝纤维化进展过程中的微循环表现,探讨超声造影在肝纤维化无创性诊断中的应用价值。方法:60只雄性大鼠,对照组8只,实验组52只建立大鼠肝纤维化模型,超声造影记录造影剂到达肝动脉时间(HAAT)、造影剂到达门静脉时间(PVAT)、造影剂到达肝静脉时间HVAT,计算肝动-静脉渡越时间(HA-HVTT),获取肝实质时间-强度曲线,记录达峰值时间、峰值强度、曲线上升斜率、下降斜率。以病理肝纤维化分期进行分组,分别以S≥1、S=4为判定肝纤维化和早期肝硬化的标准,应用ROC分析法评价超声造影诊断肝纤维化的价值。结果:以S≥1为判定肝纤维化标准,HA-HVTT曲线下面积为0.792,且曲线与机会线不相交,对肝纤维化的诊断准确性中等。以S=4为判定早期肝硬化的标准,HVAT、HA-HVTT的ROC曲线下面积均大于0.9,对早期肝硬化的诊断有统计学意义,诊断准确性较高;峰值强度、下降斜率ROC曲线下面积分别为0.828及0.852,对早期肝硬化的诊断准确性中等。结论:应用超声造影可以观察大鼠肝动脉、门静脉、肝静脉显影过程,HA-HVTT对肝纤维化(S≥1)及早期肝硬化(S=4)均有一定的诊断价值,有望成为定量诊断肝硬化的重要影像学检测指标。

Diagnostic value of contrast enhanced ultrasound in diagnosis of liver fibrosis by receiver operating characteristic curve

Objective: To estabilish liver fibrosis mode of different stage in rats and observe the trending of hemodynamic change during the development of liver fibrosis by contrast enhanced ultrasound(CEUS).To study the value of CEUS in the noninjury diagnosis of liver fibrosis.Methods: Sixty SD rats were divided to two groups,8 as control group,52 for liver fibrosis mode.Hepatic artery arrival time(HAAT),portal vein arrival time(PVAT),hepatic vein arrival time(HVAT),and hepatic artery to vein transmit time(HA-HVTT) were recorded with CEUS.In CnTI program obtain the time-intensity curve of liver parenchyma and record the time to peak,peak intensity,ascending slope,descent slope.All rats were grouped according to pathological liver fibrosis stage.ROC analysis was performed to assess the value of these methords on diagnosis of liver fibrosis(S≥1) and early liver cirrhosis(S=4).Results: ROC analysis showed AUC of HA-HVTT was 0.792 and ROC curve was not intersected with diagonal reference line,the diagnostic value was moderate.AUC of HVAT、HA-HVTT for diagnosing early liver cirrhosis(S=4) were all bigger than 0.9,the diagnostic accuracy was high;the AUC of peak intensity and descent slope for diagnosing early liver cirrhosis was 0.828 and 0.852,the diagnostic value was moderate.Conclusions: CEUS can be used to observe the developing process of the hepatic artery,portal vein,hepatic vein.HA-HVTT was helpful for evaluating liver fibrosis(S≥1) and early liver cirrhosis(S=4),and it is promising that HA-HVTT will become a significant imaging index in quantitative diagnosis of liver cirrhosis.