Ultrasonography of Normal Fetal Fourth Ventricle in the Second Trimester of Pregnancy / 中国医学影像学杂志

ABSTRACT

Purpose To characterize normal growth of the fetal fourth ventricle in the second trimester of pregnancy by standardized ultrasonography.Materials and Methods 516 cases of pregnant women with single fetus aged 18-27 weeks and 6 days were examined by conventional ultrasound.At the standard section of the fourth ventricle,the transverse dimension,anteroposterior dimension,circumference and area of the fourth ventricle were measured.Results The display rate of the fourth ventricles of fetuses aged 18-27 weeks and 6 days was up to 100％.There were no significant differences in the values of the fourth ventricles between fetuses with different gender (P＞0.05).The values of the fourth ventricle,including transverse dimension,anteroposterior dimension,circumference and area,increased linearly with the increase of gestational age,and there were positive correlations (r=0.374,0.378,0.387,0.379,P＜0.05).Conclusion The normal size of the fourth ventricle can be obtained by standardized measurement,which can be used as a reference for the clinical evaluation of the size of the fourth ventricle.