Casasbuenas Alexandra, Wong Amy E, Sepulveda Waldo
Fetal Medicine Center, Department of Obstetrics and Gynecology, Clinica Las Condes, Santiago, Chile.
Prenat Diagn. 2009 Feb;29(2):108-12. doi: 10.1002/pd.2173.
To report normative data of nasal bone length (NBL) in first-trimester singleton fetuses in a normal cohort of Latin American women.
NBL was measured during routine first-trimester sonographic examination in 1040 singleton fetuses from an unselected population.
NBL increased linearly with advancing gestational age (GA) [NBL (mm) = - 1.10 + 0.03 x GA (days), R(2) = 0.21; p < 0.001]. Similarly, there was a linear relationship between the NBL and crown-lump length (CRL) [NBL (mm) = 0.41 + 0.02 x CRL (mm), R(2) = 0.27; p < 0.001]. The NBLs at the 50th percentile in our population were 1.5, 1.7, and 1.9 mm at 11, 12, and 13 weeks of gestation, respectively.
Whereas categorizing a nasal bone as absent or present can be subjective because of variations in echogenicity due to technique and equipment, measurement of NBL is a more objective approach to nasal bone assessment in screening for aneuploidy. Measurement of NBL in the first trimester is feasible and can be easily obtained at the time of nuchal translucency assessment. The normative data we report can provide a reference for defining nasal bone hypoplasia in the first trimester in the Latin American population.
报告拉丁美洲正常女性队列中孕早期单胎胎儿鼻骨长度（NBL）的规范数据。
对来自未选择人群的1040名单胎胎儿在孕早期常规超声检查时测量NBL。
NBL随孕周（GA）增加呈线性增加[NBL（mm）=-1.10 + 0.03×GA（天），R² = 0.21；p < 0.001]。同样，NBL与顶臀长（CRL）之间存在线性关系[NBL（mm）= 0.41 + 0.02×CRL（mm），R² = 0.27；p < 0.001]。在我们的人群中，孕11、12和13周时第50百分位数的NBL分别为1.5、1.7和1.9 mm。
由于技术和设备导致的回声差异，将鼻骨分类为缺失或存在可能具有主观性，而测量NBL是在非整倍体筛查中评估鼻骨的更客观方法。孕早期测量NBL是可行的，并且在颈部透明带评估时可以轻松获得。我们报告的规范数据可为拉丁美洲人群孕早期鼻骨发育不全的定义提供参考。
