二维超声对胎儿肺部发育规律的研究

Assessment of fetal lung development in using two-dimensional ultrasonography

目的探讨二维超声测量胎儿左右肺面积、左右肺纵径、左右肺体积及总肺体积,及通过其测量值评价胎儿肺部发育的应用价值。方法 2013年6月至2014年6月在广东省妇幼保健院进行产前超声检查并足月分娩的孕妇489例,对此489例12-40周胎儿进行二维超声扫查,在四腔心切面应用Trace法分别描迹左肺、右肺面积;在胎儿左、右侧肺最大矢状切面分别测量左、右侧膈顶至左、右肺尖的距离,应用体积公式长（cm）×宽（cm）×高（cm）×0.52分别计算左、右肺体积,总肺体积。应用Bivariate法分析孕周与左右肺面积、左右肺纵径、左右肺体积及总肺体积的相关性,绘制12-40周胎儿左右肺面积、左右肺纵径、左右肺体积及总肺体积的生长曲线,获取12-40周胎儿左右肺体积及总肺体积的第5,25,50,75,95百分位数。结果 （1）孕周与胎儿左右肺面积、左右肺纵径、左右肺体积及总肺体积的Spearson相关系数分别为0.929、0.923、0.923、0.917、0.946、0.943、0.951,且呈正相关,具有统计学意义（P〈0.05）。（2）左右肺面积、左右肺纵径、左右肺体积及总肺体积测值的增长速率趋势一致,均随孕周增加而增长;肺面积在孕26周前增长速度较快,26周后增长速度减缓;肺纵径及肺体积在整个孕期呈均速增长,但肺纵径增长速度略快于肺体积。（3）成功获取12-40周胎儿左右肺体积及总肺体积的第5、25、50、75、95百分位数参考值范围。结论 12-40周胎儿左右肺面积、左右肺纵径、左右肺体积及总肺体积随孕周的增加而增长。左右肺体积及总肺体积的第5、25、50、75、95百分位数为产前诊断胎儿肺发育不良提供有价值的参考指标。获取胎儿四腔心切面及左、右侧肺最大矢状切面操作简单、便捷、可行性良好,可能成为一种新型的评价胎儿肺部发育常规手段。

Objective To explore the application value of two-dimensional ultrasonic measurement of fetal left and right lung area, left and right pulmonary longitudinal diameter, left and right lung volume and total lung volume in evaluation of fetal lung development. Methods In 489 cases of normal singleton pregnancy, two-dimensional ultrasound scanning were conducted at 12-40 weeks. The left and right lung area was traced in the four chamber view using Trace method. The distances of left diaphragmatic dome to left lung apex and the right diaphragmatic dome to right lung apex were measured respectively on the left and right fetal lung parasagittal planes. Then calculation of left and right lung volume and total lung volume was carried out. Results Spearman correlation coefficient of gestational age and left and right lung area, left and right pulmonary longitudinal diameter, left lung volume and total lung volume were 0.929, 0.923, 0.923, 0.917, 0.946, 0.943, 0.951, and a positive correlation, with statistical significance（P 0.05）. At 12-40 weeks, fetal left and right lung area, left and right pulmonary longitudinal diameter, left and right lung volume and total lung volume increased with gestational age and fetal growth. Pulmonary area increased faster before 26 weeks than that after 26 weeks. Pulmonary longitudinal diameter and lung volume grew at a constant rate throughout pregnancy, but the growth rate of pulmonary longitudinal diameter was slightly faster than that of lung volume. The fifth, twenty-fifth, fiftieth, seventy-fifth, ninetyfifth percentile of fetal left and right lung volume and total lung volume at 12-40 weeks were obtained. Conclusions Fetal left and right lung area, left and right pulmonary longitudinal diameter, left and right lung volume and total lung volume were positively correlated with gestational age between 12 and 40 week. The normal values of lung volume and total lung volume provide a reference index for prenatal diagnosis of fetal pulmonary hypoplasia. The fetal four chamber view and fetal left parasagittal section was easy to obtain, and may serve as a new conventional method in evaluating fetal lung developments.