声脉冲辐射力成像技术评价大鼠脂肪性肝炎的研究

目的探讨声脉冲辐射力成像(ARFI)技术无创评价大鼠脂肪性肝炎(NASH)的价值。方法将26只健康成年雄性无特定病原体级的SD大鼠分为对照组8只和脂肪肝组18只,根据不同喂养时间和单纯性脂肪肝(SS)、NASH诊断标准将脂肪肝组分为SS组9只和NASH组9只,分别行ARFI和CT检查,记录肝剪切波速度(SWV)和肝、脾CT值。实验到期后取其肝计算肝脏指数,并行病理分析。分析SWV值、CT值及肝脏指数与病理之间的关系,对SWV的诊断效率行ROC曲线分析,计算其敏感性和特异性。结果 SS组和NASH组肝SWV值分别为(1.01±0.02)m/s和(1.16±0.04)m/s,对照组肝SWV值(1.03±0.05)m/s,SS组与对照组间SWV值比较差异无统计学意义,SS组与NASH组间比较差异有统计意义(P﹤0.01)。SWV值与NASH有显著相关性(r=0.688)。应用SWV诊断NASH对应的ROC曲线下面积为0.91,SWV临界值为1.09 m/s,敏感性为85.7%,特异性为100%。结论 ARFI技术判断大鼠NASH有一定价值,且具有简便、无创的优势。

Evaluation of nonalcoholic steatohepatitis in a rat model by acoustic radiation force impulse elastography

Objective To investigate the value of acoustic radiation force impulse （ARFI） elastography for noninvasive evaluation on nonalcoholic steatohepatitis （NASH） in rats. Methods Twenty-six rats were divided into two groups according to different diets：a standard diet （control group, 8 rats） and a hyperlipidaemic diet （HL group, 18 rats）. According to different feeding time and diagnosis standard, HL group were divided into two subgroups, 9 rats with simple steatosis （SS） and 9 rats with NASH.The ARFI and computed tomography （CT） were performed to all rats respectively, the shear wave velocity （SWV）and the CT value of liver and spleen were measured and recorded. Data of the correlation between SWV, CT value of liver, hepatic index and histological findings were analyzed. The accuracy and specificity of the diagnosis effect of using SWV were calculated with ROC analysis. Results Mean SWV was （1.03±0.05）m/s in the control group, （1.01±0.02）m/s in the SS group and （1.16±0.04）m/s in the NASH group. Compared with the SS group, SWV was significantly higher in NASH group, there was no significant difference between rats in SS group and control group.There was a significant correlation between SWV and NASH （r=0.688）.The areas under ROC curve for the diagnosis of NASH was 0.91 （optimal cut-off value 1.09 m/s, sensitivity 85.7%, specificity 100% ）. Conclusion ARFI imaging is a non-invasive diagnostic tool that allows discrimination between the SS and NASH of liver in rats.