11～14孕周胎儿颅脑横切面筛查主要颅脑畸形的临床价值

Clinical value of a cross-sectional view of the fetal brain in screening for major brain malformations during 11—14 weeks

目的探讨11～14孕周胎儿颅脑横切面筛查主要颅脑畸形的临床价值,提高检查的诊断率。方法2004年1月-2007年6月共4985例孕妇进行11～14孕周超声检查,测量胎儿颈项透明层厚度和观察胎儿主要形态结构,重点观察胎儿颅脑横切面。结果11～14孕周超声共诊断14例主要颅脑畸形,颅盖缺失9例,全前脑2例,脑膨出3例,均引产证实;漏诊7例主要颅脑畸形,颅盖缺失3例,全前脑2例,脑膨出2例,于中孕期超声系统筛查诊断并引产证实。结论超声能在11～14孕周筛查主要颅脑畸形。胎儿颅脑横切面观察卵圆形的颅骨光环、脑中线、侧脑室及蝴蝶形的脉络膜是诊断的关键。规范的培训将增加胎儿颅脑畸形的检出率。

Objective To review the clinical value of a cross-sectional view of the fetal brain between 11-14 weeks＇ ultrasound scan, so as to avoid potential diagnostic pitfalls. Methods A total of 4985 pregnancies underwent 11-14 weeks＇ultrasound scan. Measured the thickness of nuchal translucengcy （NT） and evaluated fetal major anatomy structure, specially a cross-sectional view of the fetal brain. Results There were 14 major brain malformations detected at 11- 14 weeks and confirmed by postmortem examination, including 9 cases of acranium, 2 cases of holoprosencephaly and 3 cases of encephalocele. There were 7 major brain malformations missed at 11-14 weeks and detected at the second trimester and confirmed by postmortem examination, including 3 cases of acranium, 2 cases of holoprosencephaly and 2 cases of encephalocele. Conclusion Detection of major brain malformations is feasible during the 11- 14 weeks＇ scan. A cross-sectional view of the fetal brain is the key to detect major brain malformations during 11-14 weeks, including ovum-shaped skull, the presence of a midline, the lateral ventricles and a ＂butterfly＂ choroids plexuses. Proper criterion training should increase the detection rate of brain malformations.