灰阶超声造影对正常肝实质及VX2肿瘤血流动力学的对照研究

目的 应用低机械指数灰阶超声造影定量研究肝恶性肿瘤及其周围肝实质血流动力学特点及其诊断价值。方法 分别经耳缘静脉对8只荷VX2肿瘤新西兰大白兔团注超声造影剂SonoVue（0．1ml／kg），应用低机械指数实时灰阶造影匹配成像技术和声学定量时间一强度曲线分析软件，定量分析兔VX2瘤及其周围肝实质血流动力学特点及造影增强效应。结果低机械指数灰阶超声造影可动态显示肝实质与肿瘤内造影剂的增强过程，其时间一信号强度曲线客观反映造影剂的渡越过程。与肝实质相比，VX2瘤造影剂开始增强时间和达到峰值时间均明显提前，分别为10．13s和17．48S，峰值强度较低，渡越时间明显缩短。VX2瘤与肝实质各造影定量参数间差异具有统计学意义（P〈0．01）。结论 低机械指数灰阶超声造影能很好地反映肝恶性肿瘤血流动力学变化，超声造影定量分析对肝恶性肿瘤的诊断有重要价值。

Gray-scale contrast enhancement ultrasonography in rabbit liver and VX2 tumor

Objective To evaluate the hemodynamic features of VX_2 tumor and peri-neoplastic liver parenchyma with low mechanical index gray-scale contrast enhancement.Methods Ultrasound contrast agent SonoVue((0.1) ml/kg) was applied respectively in 8 VX_2-bearing rabbits by intravenous bolus injection.Corresponding parameters of the time-intensity curve:time to enhancement(ET),time to peak intensity(PIT),peak signal intensity(PSI) and mean transit time(MTT) were measured using low mechanical index contrast gray-scale imaging and Wash-in/Wash-out time-intensity curve software.Results Gray-scale imaging delineated clearly the dynamic enhancement of the VX_2 tumor and the surrounding liver parenchyma.The ET and PIT were definitely earlier,the PSI lower and the MTT absolutely shorter in VX_2 tumors than those in the liver parenchyma.There were significant differences of parameters derived from the time-intensity curve between VX_2 tumors and liver parenchyma(P<(0.01)).Conclusions Low mechanical index contrast gray-scale imaging and time-intensity curve fully delineate the typical enhancement pattern of VX_2 tumors,with contrast agent being washed in and washed out quickly relative to the liver parenchyma,due to exclusive dependence on arterial blood supply.This technique is much valuable for the diagnosis of malignant tumor.