兔VX2肝癌超声造影CT灌注及磁共振成像灌注定量分析的相关性研究

Study on the correlation analysis of rabbit VX2 liver cancer ultrasonic angiography with CT perfusion and MRI perfusion quantitative

目的探讨在肝癌诊断方面,超声造影定量指标与CT灌注及磁共振成像(MRI)灌注定量指标的相关性。方法开腹直视下将25只新西兰大白兔肝左叶种植VX2肿瘤组织块,建立兔VX2肝癌模型,造模后14 d分别行常规超声及实时超声造影检查,观察记录常规声像图特征及超声造影特点。利用QLab软件对造影动态图像进行时间-强度分析,得出肿瘤组织与周边正常肝组织曲线增强上升斜率(AS)、开始增强时间(AT)、达峰时间(TTP)、峰值强度(PI)、曲线下面积(AUC)及相对参数(相对参数指病灶区参数与周边正常肝组织区的参数之差值)。造影后行CT灌注得到参数血流量(BF)、血容量(BV)、表面通透性(PS)、平均通过时间(MTT)以及MRI灌注的相关参数平均强化时间(MTE)、正向增强积分(PEI)、达峰时间(TP)及最大上升斜率(MSI),处死动物后肝癌标本做MVD以及VEGF检测,然后对实验结果做相关性分析。结果超声造影的定量分析参数中相对TTP与血流量BF呈正相关(r=0.557,P=0.028),TP达峰时间与血流量BF呈正相关呈负相关(r=-0.424,P=0.035)。超声造影的定量分析参数相对PI与血流量BF及正向积分PEI均呈正相关(r=0.393、0.384,P=0.012、0.024)。结论超声造影定量指标可在一定程度上反映肿瘤内部微血管密度及血管内皮表达因子,有一定临床实用价值。超声造影的某些定量参数与CT灌注及MRI灌注的定量参数具有一定的一致性。

Objective To sum up and investigate correlation of contrast-enhanced ultrasound quantitative index with CT perfusion and MRI peffusion index in the diagnosis of hepatocellular carcinoma （HCC）. Methods Twenty- five New-Zealand white rabbits were inoculated with VX2 carcinoma in the liver by laparotomy implantation. Conven- tional color ultrasound and CEUS were performed 14 days after molding respectively, and to observe and record the sonographie characteristics of routine untrasound and CEUS. The dynamic images of CEUS were analyzed by QLAB, to get the parameters, including ascending slope （AS）, arrival time （AT）, time-to-peak （TIP）, peak intensity （PI）, area under curve （AUC） and relative parameters （the discrepancy of HCC and tissue around it）. CT and MRI peffusion weighted imaging were performed to get the parameters, including blood flow（BF）, blood volume（BV）, permeability sur- faee（PS）, mean transit time （MTT） of CT. Mean time to enhanee（MTE）, positive enhancement integral（PEI）, time to peak（TP） and maximum slope of inerease（MSI） of MRI. Finally kill the animal, the liver specimens were detected for MVD and VEGF, and then the correlation analysis were done with the experimental results. Results The relative time to peak was positive correlated to MVD and VEGF（r=0.517, 0.528, P〈0.05）, and the relative peak intensity was positive correlated to MVD（r=0.564, P〈0.01）. There was also correlation between VEGF and MVD（r=0.641, P=0.01）. Among the quantitative parameter of CEUS, relative time to peak was positive correlated to BF （r=0.557, P=0.028）, TP was negative correlation to BF（r=-0.424, P=0.035）, and the relative peak intensity was positive correlated to BF and PEI（r=0.393, 0.384,P=0.012, 0.024）. Conclusion To some extent, contrast-enhanced ultrasound quantitative pa- rameters have some clinical practical value; it can reflect tumor micro vascular distribution inside. Some quantitative parameters of CEUS has certain consistency with that of CT perfusion and MRI perfusion.