对比脉冲序列造影参数与大鼠中、晚孕胎盘血管床变化的相关性

目的 应用超声造影连续对比脉冲序列(CPS)技术定量研究造影剂在中、晚孕大鼠胎盘的灌注参数,分析胎盘造影剂灌注参数与胎盘血管床变化的关系. 方法 随机选取健康SD孕鼠60只,按实验要求分三组:孕15天、孕17天、孕20天,每组20只.应用超声造影CPS技术,机械指数0.20,经鼠尾静脉快速团注SonoVue造影剂(1.0 ml/kg),利用灌注定量分析软件(ACQ)分别得到胎盘和子宫肌壁两个感兴趣区的时间-强度曲线和相关的参数值.造影结束取出所观察的胎盘,切片染色,应用图像分析软件测量胎盘母体血管平均面积密度. 结果 孕17天、20天两组胎盘造影剂峰值强度(PI)高于孕15天胎盘,差异有统计学意义(P＜0.05).孕17天、20天两组胎盘造影剂灌注PI间差异无统计学意义(P＞0.05).造影剂到达时间、造影剂达峰值强度所用时间三组之间差异无统计学意义(P＞0.05).三组胎盘绒毛间隙母体血管床的面积密度间差异有统计学意义(P＜0.05).三组胎盘PI与胎盘绒毛间隙母体血管面积密度呈正相关(P＜0.05). 结论 胎盘造影剂PI与胎盘绒毛间隙母体血管面积密度有密切相关性.造影连续CPS技术可以敏感地反映胎盘发育过程中血管床的变化.

Relationship between contrast pulsed sequencing parameters and changes of placental vascular bed in different stage of pregnant rats

Objective To quantitatively measure the perfusion parameters of placenta in different stage of pregnant rats using contrast-enhanced ultrasonography (CEUS) with contrast pulsed sequencing (CPS), and to analyze the relationship between perfusion parameters and changes of placental vascular bed. Methods Sixty healthy pregnant rats in according to the requirements of the experiment was divided into three groups: 15 days, 17 days and 20 days of gestation with 20 animals in each group. One blous injection of SonoVue (Sonovue 1.0 ml/kg) via a tail vein was administered to each rat, and the time-intensity curves (TIC) of placenta and uterine muscle wall were drawn with ACQ using CPS technique with MI 0.20, and the perfusion parameters were calculated. Then 4 μm vertical placenta sections were cut and stained with hematoxylin and eosin. Surface area densities of placental maternal blood space was measured with image analysis software. Results The peak intensity (PI) of 17 days and 20 days was higher than that of 15 days pregnant rats (P＜0.05). There was no difference in PI between 17 days and 20 days (P＞0.05), and nor of arrivel time (AT) and time-to-peak (TTP) (P＞0.05) among the three groups. There was significant difference of surface area densities of placental maternal blood space among the three groups (P＜0.05). PI was positively correlated to the surface area densites of placenta (P＜0.05). Conclusion There is close relationship between peak intensity and area densities of placental maternal blood space. CPS technique can sensitivly detect changes of the placenta vascular bed in different stage of pregnant rats.