孕16～18周超声检查在核型正常但颈项透明层增厚胎儿中的临床应用价值

摘要

目的 探讨孕16～18周胎儿超声结构筛查在颈项透明层(nuchal translucency,NT)增厚但核型正常胎儿中的临床应用价值. 方法 2015年1月至2017年6月在广州市番禺区中心医院行早孕期超声检查提示胎儿NT增厚(≥3.0 mm)的214例孕妇,随后行介入性产前诊断染色体核型分析,对核型结果正常的病例,分别于孕16～18周和孕20～24周时行超声结构筛查,并电话随访妊娠结局.描述性统计分析检出畸形情况. 结果 214例NT增厚病例中,198例完成了核型分析,39％(78/198)检出染色体异常而终止妊娠.在核型正常并成功随访的107例孕妇中共检出37例(35％)结构畸形.在孕11～13周16、孕16～18周和孕20～24周分别检出19、11和6例结构畸形,另外1例在孕28周时检出结构畸形.孕16～18周检出的结构畸形分别为唇腭裂、心脏畸形、脊柱畸形、肢体畸形各2例,膈疝、脑膨出、左肾多囊性发育不良各1例.当核型正常且孕16～1 8周胎儿超声结构筛查未见异常时,91％(70/77)的NT增厚胎儿未发现结构畸形,活产分娩.结论 NT增厚胎儿染色体核型正常时,孕16～18周超声结构筛查能检出大部分结构畸形,将胎儿结构畸形的检出时间提前.%Objective To investigate the diagnostic value of ultrasound scan at 16 to 18 gestational weeks in euploid fetuses with increased nuchal translucency (NT).Methods From January 2015 to June 2017,214 fetuses diagnosed with increased NT thickness (NT ≥ 3.0 mm) during early pregnancy in Guangzhou Panyu Central Hospital were enrolled.Fetal chromosome karyotype analysis was carried out prenatally.Those cases with normal karyotype underwent ultrasound scan at 16-18 and 20-24 gestational weeks and their outcomes were followed up via telephone.Descriptive statistics was used for statistical analysis.Results There were 198 out of the 214 cases undergoing chromosome karyotype analysis and among them,78 (39％) pregnancies were terminated due to chromosomal abnormalities.Out of the 107 cases with normal karyotype and successful followups,35％(37/107) had structural malformations.There were 19,11 and 6 cases of fetal structural malformations diagnosed at 11-13+6,16-18 and 20-24 weeks of gestational age,respectively,and the rest one was at 28 weeks.Structural deformities detected at 16-18 weeks included cleft lip and palate (n=2),cardiac malformations (n=2),spinal deformities (n=2),body deformities (n=2),diaphragmatic hernia (n=1),encephalocele (n=1) and left multicystic dysplastic kidney (n=1).About 91％ (70/77) of the fetuses with normal karyotype but without abnormal ultrasound findings at 16-18 weeks were free of structural malformations and achieved good pregnant outcomes.Conclusions Ultrasound screening at 16 to 18 weeks of pregnancy can be used to detect multiple structural malformations in fetuses with increased NT and normal karyotype,which may contribute to early detection of fetal structural malformations and help gravidas and their families make timely decisions.