Scott A
Issues Emerg Health Technol. 2007 Jun(100):1-6.
(1) Approximately three in every four fetuses with Down syndrome have increased nuchal translucency (NT), which is a larger than normal build-up of fluid at the back of the neck. (2) The ultrasound measurement of NT between 11 and 14 weeks' gestation, in combination with the mother's age and the levels of placental biochemical markers in her blood, can be used to detect approximately 84% of fetuses with Down syndrome. (3) The accuracy of NT measurement is affected by fetal position, measurement technique, the type of risk-calculation software used, and the sonographer's experience and technical expertise. (4) A rigorous standardization and quality assurance system for NT measurement is needed before any test using NT ultrasound is offered universally. The cost of establishing such a program is unknown.
（1）每四个患有唐氏综合征的胎儿中约有三个会出现颈部透明带（NT）增厚，即颈部后方液体堆积超过正常水平。（2）在孕11至14周期间对NT进行超声测量，结合母亲年龄和其血液中胎盘生化标志物水平，可用于检测约84%的唐氏综合征胎儿。（3）NT测量的准确性受胎儿位置、测量技术、所用风险计算软件类型以及超声检查人员的经验和技术专长影响。（4）在普遍提供任何使用NT超声的检测之前，需要建立严格的NT测量标准化和质量保证体系。建立这样一个项目的成本尚不清楚。
