【摘要】 目的利用MRI体积测量技术精确测量胎儿肾脏体积,并分析其与孕周、羊水指数(AFI)、胎儿性别等因素的关系。方法对5只兔的10只肾脏采用5mm层厚、0.5mm层间距进行T2WI横、矢、冠状位扫描,分别测量出体积;扫描后解剖取肾脏测量实际体积,计算MRI各方位测量的误差率,找出最佳方位;采用与动物实验相同层厚与间距及最佳方位对114例30～39孕周无泌尿系统异常(经MRI检查和随访确认)胎儿双侧肾脏进行MRI扫描,测量出肾脏体积,进行统计分析。结果 (1)兔的MRI肾脏体积测量最佳扫描方位为横轴位,MRI测量误差率为(2.26±0.55)%;(2)胎儿平均肾脏体积由30孕周的(6.42±1.28)cm3逐渐增长至39孕周的(14.14±2.26)cm3,与孕周相关系数r=0.766(P<0.05),与AFI相关系数r=0.179(P>0.05);相同孕周男性肾脏体积大于女性(P<0.05)。结论 MRI体积测量技术可以精确测量胎儿肾脏体积;胎儿肾脏体积与孕周呈正相关,与AFI无明显相关性,有性别差异。更多还原

【Abstract】 Objective To measure the volume of fetal kidney using MRI accurately and explore its correlation with gestational weeks(GW),amnion fluid index(AFI) and gender.Methods First,five rabbits were examined by MRI with axial,sagittal and coronal sections and with slices thickness of 5 mm and interval space of 0.5 mm.Then the volume of 10 kidneys from 5 rabbits was measured on the workstation of MRI system.After autopsy,the volume of 10 kidneys was practically measured,and MRI error rate was calculated.In addition,the best scanning section was chosen.Second,MRI volumetic measurement of fetal kidney was performed through the best scanning section in 114 heathy fetus ranging from 30 to 39 weeks gestation without any uninary abnormalitity,which was confirmed by MRI and follow-up.Statistical analysis was used for all data.Results(1) The mean volume of the true rabbit kidneys was(10.75 ± 1.97) cm3.The best scanning section was axial and the mean MRI error rate was(2.26 ± 0.55) % .(2) The mean volume of the fetal kidney at 30th GW was(6.42 ± 1.28) cm3 and become as large as(14.14 ± 2.26) cm3 at 39th GW.The correlation coefficient of the renal volume with GW was r = 0.766(P < 0.05) and with AFI r = 0.179(P > 0.05) .The renal volume of male fetuses was bigger than that of female at the same GW(P < 0.05) .Conclusions The volume of fetal kidney could be measured by MRI accurately and it was correlated with GW,but not with AFI.The volume of male fetuses was bigger than that of female fetuses.更多还原