Dagklis T, Borenstein M, Peralta C F A, Faro C, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2006 Sep;28(3):261-5. doi: 10.1002/uog.2841.
To investigate the mid-facial hypoplasia of fetuses with trisomy 21 at 11 + 0 to 13 + 6 weeks of gestation, by three-dimensional (3D) evaluation of the maxilla and the nasal bones.
A 3D volume of the fetal head was obtained before fetal karyotyping at 11 + 0 to 13 + 6 (median 12) weeks of gestation in 80 fetuses that were subsequently found to have trisomy 21 and in 862 fetuses subsequently found to be chromosomally normal. The multiplanar mode was used to obtain a sequence of transverse views of the fetal face and to demonstrate the maxilla, the adjacent rami of the mandible and the nasal bones. The maxillary depth, defined as the distance between the alveolus of the maxilla in the midline anteriorly and the midpoint of the line joining the rami posteriorly, was measured. Ossification of the nasal bones was considered to be normal if both bones were more echogenic than the overlying skin.
In the chromosomally normal group the maxillary depth increased linearly with crown-rump length (CRL) from 3.1 mm at a CRL of 45 mm to 4.8 mm at a CRL of 84 mm, and in the trisomy 21 fetuses the depth was significantly smaller than normal (mean difference = - 0.3 mm, P < 0.001). There was no significant association between the delta maxillary depth and delta nuchal translucency thickness in either the trisomy 21 or the chromosomally normal fetuses. Impaired ossification of the nasal bones was observed in 3.1% of the chromosomally normal fetuses and in 60.0% of those with trisomy 21. The mean maxillary depth was significantly smaller in fetuses demonstrating impaired ossification than in those with normal ossification of the nasal bones (mean difference = -0.2 mm; 95% CI, -0.3 to -0.1, P = 0.001).
In a high proportion of fetuses with trisomy 21 there is sonographic evidence of mid-facial hypoplasia at 11 + 0 to 13 + 6 weeks of gestation.
通过对上颌骨和鼻骨进行三维评估，研究孕11⁺⁰至13⁺⁶周21-三体胎儿的面中部发育不全情况。
在孕11⁺⁰至13⁺⁶周（中位值12周）进行胎儿核型分析前，获取80例随后被诊断为21-三体胎儿以及862例随后被诊断为染色体正常胎儿的胎儿头部三维容积数据。使用多平面模式获取胎儿面部的一系列横断图像，以显示上颌骨、下颌骨相邻支以及鼻骨。测量上颌深度，即上颌骨中线前部牙槽与后部下颌支连线中点之间的距离。若双侧鼻骨回声均强于其上方皮肤，则认为鼻骨骨化正常。
在染色体正常组中，上颌深度随头臀长（CRL）呈线性增加，CRL为45 mm时为3.1 mm，CRL为84 mm时为4.8 mm；而在21-三体胎儿中，上颌深度明显小于正常胎儿（平均差值=-0.3 mm，P<0.001）。在21-三体胎儿和染色体正常胎儿中，上颌深度差值与颈项透明层厚度差值之间均无显著相关性。在染色体正常胎儿中，3.1%观察到鼻骨骨化受损；在21-三体胎儿中，这一比例为60.0%。鼻骨骨化受损的胎儿平均上颌深度明显小于鼻骨骨化正常的胎儿（平均差值=-0.2 mm；95%可信区间，-0.3至-0.1，P=0.001）。
在很大比例的21-三体胎儿中，孕11⁺⁰至13⁺⁶周时超声检查有面中部发育不全的证据。
