Odibo Anthony O, Sehdev Harish M, Gerkowicz Sabrina, Stamilio David M, Macones George A
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
Am J Obstet Gynecol. 2008 Sep;199(3):281.e1-5. doi: 10.1016/j.ajog.2008.06.078.
The purpose of this study was to compare the efficiency of second-trimester nasal bone hypoplasia (NB) and increased nuchal fold (NF) in Down syndrome screening.
This was a prospective multicenter cohort study of women who underwent an anatomic survey between 16 and 22 weeks of gestation. The fetal NB and other markers of fetal aneuploidy that included NF were evaluated. NB was defined either as an absent NB or length of <0.75 multiples of the median for the gestational age. Two definitions of increased NF (>5 mm and >6 mm) were evaluated. Fetuses or infants with Down syndrome were compared with those fetuses without for the presence of NB and increased NF.
Among 4373 pregnancies that were evaluated over a 5-year period, there were 50 pregnancies with Down syndrome. NB evaluation was obtained in 3936 of 4373 pregnancies (90%); NF was evaluated in all of the fetuses. Absent NB was seen in 14/49 cases (29%), and NF of >6 mm was seen in 6 of 50 cases (12%) with Down syndrome.
Nasal bone and nuchal fold are efficient markers for Down syndrome. Absent nasal bone was a better predictor of Down syndrome, compared with nuchal fold, and should be a standard marker when a second-trimester genetic sonogram is performed.
本研究旨在比较孕中期鼻骨发育不全（NB）和颈项透明层增厚（NF）在唐氏综合征筛查中的效率。
这是一项对妊娠16至22周期间接受解剖学检查的女性进行的前瞻性多中心队列研究。评估了胎儿的NB以及包括NF在内的其他胎儿非整倍体标志物。NB定义为无鼻骨或鼻骨长度小于胎龄中位数的0.75倍。评估了两种NF增厚的定义（>5mm和>6mm）。将唐氏综合征胎儿或婴儿与无唐氏综合征的胎儿进行比较，以确定是否存在NB和NF增厚。
在5年期间评估的4373例妊娠中，有50例妊娠为唐氏综合征。4373例妊娠中有3936例（90%）进行了NB评估；所有胎儿均进行了NF评估。唐氏综合征的49例病例中有14例（29%）无鼻骨，50例病例中有6例（12%）NF>6mm。
鼻骨和颈项透明层是唐氏综合征的有效标志物。与颈项透明层相比，无鼻骨是唐氏综合征更好的预测指标，在进行孕中期基因超声检查时应作为标准标志物。
