超声测量胎儿颈项透明层厚度的临床意义

Clinical significance of ultrasound measurement of fetal neck transparent layer thickness

目的探讨超声测量胎儿颈项透明层(NT)厚度的临床意义。方法选取2016年1月~2017年12月在我院进行NT厚度测量的孕11~13^+6周单胎孕妇3013例的资料实施分析,按NT厚度将其依次分为5组,<2.5、2.5~3.4、3.5~5.4、5.5~6.4、≥6.5mm,对胎儿NT厚度≥2.5mm孕妇开展随访,通过绒毛穿刺、羊水穿刺或脐血穿刺获得染色体核型结果,在孕妇20~24周通过超声筛查胎儿是否存在其他结构畸形。结果3013例孕妇接受超声测量胎儿NT厚度显示正常孕妇2899例,检测胎儿NT厚度≥2.5mm的孕妇90例,在90例NT厚度≥2.5mm胎儿中,具有染色体核型异常24例(21.05%),染色体异常发生率分别为15.38%(8/52)、35.71%(10/28)、50.00%(3/6)及75.00%(3/4),具有严重心脏畸形9例,具有颈部水囊瘤8例,具有其他结构异常7例。NT厚度≥6.5mm胎儿染色体异常检出率高于NT厚度2.5~3.4、3.5~5.4、5.5~6.4mm组。结论在妊娠早期通过超声检查胎儿NT厚度可作为胎儿染色体异常介入性产前诊断的重要超声筛查指标,胎儿NT增厚与胎儿染色体异常、严重心脏畸形和其他结构异常等有关,随着NT值的增加,胎儿染色体异常、严重心脏畸形和其他结构异常的发生率升高。

Objective To explore the clinical significance of measuring the thickness of fetal neck transparent layer(NT)by ultrasound.Methods From January 2016 to December 2017,3013 single pregnant women with NT thickness measured in our hospital during 11-13^+6 weeks of pregnancy were selected and divided into 5 groups according to NT thickness,which were<2.5 mm,2.5-3.4 mm,3.5-5.4 mm,5.5-6.4 mm and(≥6.5 mm).Follow-up was conducted for pregnant women with NT thickness(>2.5 mm).Chromosome nuclei were obtained by villus puncture,amniocentesis or umbilical cord blood puncture.Ultrasound was used to screen fetuses for other structural abnormalities from 20 to 24 weeks of gestation.Results The results of fetal NT thickness measured by ultrasound in 3013 pregnant women showed that there were 2899 normal pregnant women,90 pregnant women whose NT thickness was more than 2.5 mm.Among90 pregnant women whose NT thickness was more than 2.5 mm,24(21.05%)had chromosomal abnormalities,and the incidence of chromosomal abnormalities were 15.38%(8/52),35.71%(10/28),50.00%(3/6)and 75.00%(3/4),respectively.There were 8 cases of cervical cystadenoma and 7 cases of other structural abnormalities.The detection rate of chromosomal abnormalities in fetuses with NT thickness(>6.5 mm)was higher than that in fetuses with NT thickness of2.5-3.4 mm,3.5-5.4 mm and 5.5-6.4 mm.Conclusion Ultrasound examination of fetal NT thickness in early pregnancy can be used as an important ultrasound screening index for interventional prenatal diagnosis of fetal chromosomal abnormalities,fetal NT hypertrophy is associated with fetal chromosomal abnormalities,severe heart malformations and other structural abnormalities.With the increase of NT value,the incidence of fetal chromosomal abnormalities,severe heart malformations and other structural abnormalities increases.