Cicero S, Longo D, Rembouskos G, Sacchini C, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2003 Jul;22(1):31-5. doi: 10.1002/uog.170.
To examine the association between absence of the nasal bone at the 11-14-week ultrasound scan and chromosomal defects.
Ultrasound examination was carried out in 3829 fetuses at 11-14 weeks' gestation immediately before fetal karyotyping. At the scan the fetal crown-rump length (CRL) and nuchal translucency (NT) thickness were measured and the fetal profile was examined for the presence or absence of the nasal bone. Maternal characteristics including ethnic origin were also recorded.
The fetal profile was successfully examined in 3788 (98.9%) cases. In 3358/3788 cases the fetal karyotype was normal and in 430 it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related firstly to the ethnic origin of the mother (2.8% for Caucasians, 10.4% for Afro-Caribbeans and 6.8% for Asians), secondly to fetal CRL (4.6% for CRL of 45-54 mm, 3.9% for CRL of 55-64 mm, 1.5% for CRL of 65-74 mm and 1.0% for CRL of 75-84 mm) and thirdly, to NT thickness, (1.8% for NT < 2.5 mm, 3.4% for NT 2.5-3.4 mm, 5.0% for NT 3.5-4.4 mm and 11.8% for NT > or = 4.5 mm. In the chromosomally abnormal group the nasal bone was absent in 161/242 (66.9%) with trisomy 21, in 48/84 (57.1%) with trisomy 18, in 7/22 (31.8%) with trisomy 13, in 3/34 (8.8%) with Turner syndrome and in 4/48 (8.3%) with other defects.
At the 11-14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT thickness and ethnic origin.
研究孕11 - 14周超声检查时鼻骨缺失与染色体缺陷之间的关联。
对3829例孕11 - 14周的胎儿在进行胎儿核型分析前立即进行超声检查。检查时测量胎儿头臀长（CRL）和颈部透明带（NT）厚度，并检查胎儿面部以确定鼻骨是否存在。还记录了包括种族在内的母亲特征。
3788例（98.9%）成功检查了胎儿面部。3788例中3358例胎儿核型正常，430例异常。在染色体正常组中鼻骨缺失的发生率首先与母亲的种族有关（白种人为2.8%，非裔加勒比人为10.4%，亚洲人为6.8%），其次与胎儿CRL有关（CRL为45 - 54 mm时为4.6%，CRL为
