Cicero S, Rembouskos G, Vandecruys H, Hogg M, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2004 Mar;23(3):218-23. doi: 10.1002/uog.992.
To update the likelihood ratio for trisomy 21 in fetuses with absent nasal bone at the 11-14-week scan.
Ultrasound examination of the fetal profile was carried out and the presence or absence of the nasal bone was noted immediately before karyotyping in 5918 fetuses at 11 to 13+6 weeks. Logistic regression analysis was used to examine the effect of maternal ethnic origin and fetal crown-rump length (CRL) and nuchal translucency (NT) on the incidence of absent nasal bone in the chromosomally normal and trisomy 21 fetuses.
The fetal profile was successfully examined in 5851 (98.9%) cases. In 5223/5851 cases the fetal karyotype was normal and in 628 cases it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related first to the ethnic origin of the mother, being 2.2% for Caucasians, 9.0% for Afro-Caribbeans and 5.0% for Asians; second to fetal CRL, being 4.7% for CRL of 45-54 mm, 3.4% for CRL of 55-64 mm, 1.4% for CRL of 65-74 mm and 1% for CRL of 75-84 mm; and third to NT, being 1.6% for NT < or = 95th centile, 2.7% for NT > 95th centile-3.4 mm, 5.4% for NT 3.5-4.4 mm, 6% for NT 4.5-5.4 mm and 15% for NT > or = 5.5 mm. In the chromosomally abnormal group there was absent nasal bone in 229/333 (68.8%) cases with trisomy 21 and in 95/295 (32.2%) cases with other chromosomal defects. Logistic regression analysis demonstrated that in the chromosomally normal fetuses significant independent prediction of the likelihood of absent nasal bone was provided by CRL, NT and Afro-Caribbean ethnic group, and in the trisomy 21 fetuses by CRL and NT. The likelihood ratio for trisomy 21 for absent nasal bone was derived by dividing the likelihood in trisomy 21 by that in normal fetuses.
At the 11-14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT and ethnic origin.
更新孕11 - 14周超声检查时鼻骨缺失胎儿21三体综合征的似然比。
对5918例孕11至13⁺⁶周的胎儿进行胎儿面部超声检查，并在核型分析前即刻记录鼻骨的有无。采用逻辑回归分析，研究母亲种族、胎儿头臀长（CRL）和颈项透明层（NT）对染色体正常及21三体胎儿鼻骨缺失发生率的影响。
成功检查胎儿面部5851例（98.9%）。5851例中，5223例胎儿核型正常，628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2.2%，非裔加勒比人为9.0%，亚洲人为5.0%；其次与胎儿CRL有关，CRL为45 - 54 mm时为4.7%，55 - 64 mm时为3.4%，65 - 74 mm时为1.4%，75 - 84 mm时为1%；第三与NT有关，NT≤第95百分位数时为1.6%，NT＞第95百分位数至3.4 mm时为2.7%，NT 3.5 - 4.4 mm时为5.4%，NT 4.5 - 5.4 mm时为6%，NT≥5.5 mm时为15%。在染色体异常组中，21三体综合征的333例中有229例（68.8%）鼻骨缺失，其他染色体缺陷的295例中有95例（3
