中晚孕期超声筛查胎儿染色体异常的有效性及应用价值研究

目的 研究中晚孕期超声筛查胎儿染色体异常的有效性及应用价值.方法 经超声筛查为结构异常的中晚孕期胎儿和经孕母血清筛查为高风险的中期妊娠胎儿,行羊膜腔或脐静脉穿刺取羊水或脐血,作染色体核型诊断.结果 ①超声筛查接受检查的结构异常胎儿31例,检出异常染色体8例,检出率为25.8%.31例中颈部淋巴囊肿伴水肿3例,全部染色体异常;单纯颈项皮肤增厚3例,其中2例染色体异常;多发畸形、Dandy-Walker畸形及前脑无裂畸形各1例,染色体均异常.②血清筛查接受检查的唐氏综合征和18-三体高风险孕妇516例,检出异常染色体14例,检出率为2.71%.14例中唐氏综合征7例,其他染色体异常7例.③单纯超声筛查和血清筛查共筛查为高危又接受诊断者544(516+28)例,检出异常染色体21(14+7)例,两种方法互补染色体异常检出率为3.86%.互补筛查检出率是血清筛查的1.42倍,比血清筛查提高42.43%.结论 ①中晚孕期超声显示的某些胎儿结构异常是提示胎儿染色体异常的有效指征.②超声和血清两种筛查方法互补,可以提高染色体异常的检出率,对于血清失筛查或筛查低危漏诊孕妇是有效的弥补措施.

Clinical value and effectiveness of sonography screening for fetal chromosomal abnormalities in the middle and late pregnancy

Objective To evaluate the clinical value and effectiveness of ultrasound screening for fetal chromosomal abnormalitie in the middle and late pregnancy. Methods Fetuses who were detected with abnormal ultrasound findings during the middle and late pregnancy, and high risk of maternal serum screening underwent amnioeentesis or eordocentesis for fetal chromosome karyotypes. Results (1) A total of 31 cases with fetal malformation diagnosed by ultrasound were analysed for fetal chromosome karyotypes, and 8 (25.8%) cases were proved with fetal abnormal chromosome karyotypes. There were 3 cases of cervical springwater cyst accompany with edema,and all were fetal abnormal chromosome karyotypes. There were 3 cases of cervical pachyderma,and 2 were fetal abnormal chromosome karyotypes. There was one case with multiple malformations, one with Dandy-Walker malformation and one with holoprosencephaly malformation,all were revealed fetal abnormal chromosome karyotypes. (2) A total of 516 cases with high risk of Down's syndrome and trisomy 18 by maternal serum screening were analysed for fetal chromosome karyotypes,and 14(2.710%) cases were proved with fetal abnormal chromosome karyotypes, which include 7 cases of Down's syndrome and 7 cases of other fetal abnormal chromosome karyotypes. (3) A total of 544 (516 + 28)cases with high risk by the combination of ultrasound and maternal serum screening were analysed for fetal chromosome karyotypes, and 21 (3.86%) cases were proved with fetal abnormal chromosome karyotypes, the rate of detection higher than only maternal serum screening 42.43%.Conclusions Fetal structure abnormalities were the effective ultrasound signs for fetus chromosomal abnormalities screening in the middle and late pregnancy. The combination of ultrasound and maternal serum screening can improve the rate of fetus chromosomal abnormalities screening and be an effective way to retrieve false-positive and lower risk of maternal serum screening.