Jung Eui, Won Hye-Sung, Lee Pil Ryang, Kim Ahm
Department of Obstetrics and Gynecology, College of Medicine, KyungHee University, Seoul, Korea.
Prenat Diagn. 2007 Feb;27(2):154-7. doi: 10.1002/pd.1641.
To establish the reference range of fetal nasal bone length (NBL) in the second trimester in the Korean population and to determine its clinical value in screening for trisomy 21.
A total of 3019 consecutive fetuses at 16-28 weeks of gestation underwent ultrasonographic measurement of NBL at Asan Medical Center from October 2003 to August 2005.
Fetal profile was successfully examined in 95.6% (2885/3019) of the fetuses. NBL increased linearly with advanced gestation (R(2) = 0.4337, p < 0.001). During this period, 23 fetuses with chromosomal abnormalities (including nine with trisomy 21, two with trisomy 18, and three with Turner syndrome) were detected. In trisomy 21, hypoplastic nasal bone (<2.5th percentile) was seen in 3/9 fetuses, and the NBL of one fetus was between the 2.5th and 5th percentile. Hypoplastic nasal bone was seen in 3.1% (89/2833) of fetuses with normal chromosomal or postnatal examination findings.
We present the normal range of NBL in the second trimester in the Korean population and also their linear relationship with gestational age (GA). The NBL appears to be shorter in Korean fetuses than Caucasian and Chinese fetuses. This indicates that the normal range would vary between races and that a relative percentile is a more reliable screening criterion than an absolute value.
建立韩国人群孕中期胎儿鼻骨长度（NBL）的参考范围，并确定其在21三体综合征筛查中的临床价值。
2003年10月至2005年8月，在峨山医疗中心，对3019例孕16 - 28周的连续胎儿进行了NBL的超声测量。
95.6%（2885/3019）的胎儿成功进行了胎儿面部检查。NBL随孕周增加呈线性增加（R² = 0.4337，p < 0.001）。在此期间，检测到23例染色体异常胎儿（包括9例21三体综合征、2例18三体综合征和3例特纳综合征）。在21三体综合征中，9例胎儿中有3例鼻骨发育不全（<第2.5百分位数），1例胎儿的NBL在第2.5至第5百分位数之间。在染色体或出生后检查结果正常的胎儿中，3.1%（89/2833）出现鼻骨发育不全。
我们给出了韩国人群孕中期NBL的正常范围及其与孕周（GA）的线性关系。韩国胎儿的NBL似乎比白种人和中国胎儿短。这表明正常范围在不同种族之间会有所不同，相对百分位数比绝对值是更可靠的筛查标准。
