Borenstein M, Dagklis T, Csapo B, Sotiriadis A, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2006 Dec;28(7):870-5. doi: 10.1002/uog.3858.
To investigate the incidence of brachycephaly and frontal lobe hypoplasia in fetuses with trisomy 21 at 11 + 0 to 13 + 6 weeks of gestation.
A three-dimensional (3D) volume of the fetal head was obtained before fetal karyotyping at 11 + 0 to 13 + 6 (median, 12 + 5) weeks of gestation in 100 fetuses that were subsequently found to have trisomy 21 and in 300 fetuses subsequently found to be chromosomally normal. The multiplanar mode was used to obtain a sequence of transverse views of the fetal head and to demonstrate the biparietal and suboccipitobregmatic views. We measured the biparietal diameter (BPD), the occipitofrontal diameter (OFD) and the frontothalamic distance (FTD) between the inner table of the frontal bone and the posterior thalami.
In the chromosomally normal group the BPD, OFD and FTD increased linearly with crown-rump length (CRL) from 16.7 mm, 19.0 mm and 12.1 mm at a CRL of 45 mm to 26.7 mm, 31.7 mm and 18.7 mm, respectively, at a CRL of 84 mm. In the trisomy 21 fetuses, compared to normal fetuses, there was shorter BPD (mean difference = -0.63 mm; 95% CI, -0.97 to -0.30 mm, P < 0.0001), OFD (mean difference = -1.41 mm; 95% CI, -1.75 to -1.07 mm, P < 0.0001) and FTD (mean difference = -0.77 mm; 95% CI, -1.02 to -0.54 mm; P < 0.0001) and higher BPD to OFD ratio (mean difference = 0.022; 95% CI, 0.012 to 0.032, P < 0.0001) but no significant difference in the FTD to OFD ratio (mean difference = 0.004; 95% CI, -0.006 to 0.013, P = 0.448).
In fetuses with trisomy 21 at 11 + 0 to 13 + 6 weeks of gestation there is evidence of brachycephaIy but not of frontal lobe hypoplasia.
研究孕11⁺⁰至13⁺⁶周21-三体胎儿短头畸形和额叶发育不全的发生率。
对100例随后被诊断为21-三体的胎儿以及300例随后被诊断为染色体正常的胎儿，在孕11⁺⁰至13⁺⁶（中位值12⁺⁵）周进行胎儿核型分析前获取胎儿头部的三维容积。采用多平面模式获取胎儿头部的一系列横切面图像，并显示双顶径和枕额径切面。我们测量了双顶径（BPD）、枕额径（OFD）以及额骨内板与丘脑后部之间的额丘脑距离（FTD）。
在染色体正常组中，双顶径、枕额径和额丘脑距离随头臀长（CRL）呈线性增加，在CRL为45 mm时分别为16.7 mm、19.0 mm和12.1 mm，在CRL为84 mm时分别为26.7 mm、31.7 mm和18.7 mm。在21-三体胎儿中，与正常胎儿相比，双顶径更短（平均差值=-0.63 mm；95%CI，-0.97至-0.30 mm，P<0.0001）、枕额径更短（平均差值=-1.41 mm；95%CI，-1.75至-1.07 mm，P<0.0001）、额丘脑距离更短（平均差值=-0.77 mm；95%CI，-1.02至-0.54 mm；P<0.0001），且双顶径与枕额径比值更高（平均差值=0.022；95%CI，0.012至0.032，P<0.0001），但额丘脑距离与枕额径比值无显著差异（平均差值=0.004；95%CI，-0.006至0.013，P=0.448）。
孕11⁺⁰至13⁺⁶周的21-三体胎儿有短头畸形的证据，但无额叶发育不全的证据。
