Benacerraf B R, Frigoletto F D, Cramer D W
Radiology. 1987 Jun;163(3):811-3. doi: 10.1148/radiology.163.3.2953039.
In an expanded series of patients a sonographic sign was found to correlate well with the diagnosis of Down syndrome in second-trimester fetuses. The sign is characterized by soft-tissue thickening at the back of the fetal occiput. Sonographic evaluation for this sign was done in 2,121 consecutive fetuses between 15 and 20 gestational weeks of age at the time of genetic amniocentesis. The mothers were 35 years old or older or were otherwise at increased risk for fetal trisomies. Ten fetuses had Down syndrome by karyotype and four of these (40%) had thickened soft tissues (6 mm or more) at the back of the neck or occiput. When these data are combined with those in series previously reported by the authors, similarly collected consecutively, total second-trimester fetuses studied equals 3,825. Nine of the 21 (42%) Down syndrome fetuses by karyotype from this 3,825 had the positive sonographic sign described.
在一组扩大的患者中，发现一种超声征象与孕中期胎儿唐氏综合征的诊断密切相关。该征象的特征是胎儿枕后部软组织增厚。在进行遗传羊膜穿刺术时，对2121例孕龄在15至20周之间的连续胎儿进行了该征象的超声评估。这些母亲年龄在35岁及以上，或因其他原因胎儿三体风险增加。通过核型分析，有10例胎儿患有唐氏综合征，其中4例（40%）在颈部或枕部后方有软组织增厚（6毫米或以上）。当这些数据与作者之前连续收集并报告的系列数据相结合时，孕中期研究的胎儿总数为3825例。在这3825例经核型分析诊断为唐氏综合征的21例胎儿中，有9例（42%）出现了上述阳性超声征象。
