Ferreira Carolina, Rouxinol-Dias Ana Lidia, Loureiro Teresa, Nicolaides Kypros
a Medical School, University of Porto , Porto , Portugal.
b Center for Research in Health Technologies and Information Systems (CINTESIS), Medical School, University of Porto , Porto , Portugal.
J Matern Fetal Neonatal Med. 2019 Jun;32(12):2079-2083. doi: 10.1080/14767058.2018.1425833. Epub 2018 Jan 16.
To examine the subarachnoid space diameters in chromosomally abnormal fetuses at 11-13 weeks' gestation.
Stored three-dimensional (3D) ultrasound volumes of the fetal head at 11-13 weeks' gestation from 407 euploid and 88 chromosomally abnormal fetuses (trisomy 21, n = 40; trisomy 18, n = 19; trisomy 13, n = 7; triploidy, n = 14; Turner syndrome, n = 8) were analyzed. The subarachnoid space diameters, measured in the sagittal and transverse planes of the fetal head, in relation to biparietal diameter (BPD) in each group of aneuploidies was compared to that in euploid fetuses. A total of 20 head volumes were randomly selected and all the measurements were recorded by two different observers to examine the interobserver variability in measurements.
In euploid fetuses, the anteroposterior, transverse and sagittal diameters of the subarachnoid space increased with BPD. The median of the observed to expected diameters for BPD were significantly increased in triploidy and trisomy 13 but were not significantly altered in trisomies 21 and 18 or Turner syndrome. In triploidy, the subarachnoid space diameters for BPD were above the 95th centile of euploid fetuses in 92.9% (13 of 14) cases. The intraclass reliability or agreement was excellent for all three subarachnoid space diameters.
Most fetuses with triploidy at 11-13 weeks' gestation demonstrate increased subarachnoid space diameters.
研究孕11 - 13周染色体异常胎儿的蛛网膜下腔直径。
分析了407例整倍体胎儿和88例染色体异常胎儿（21 - 三体综合征40例、18 - 三体综合征19例、13 - 三体综合征7例、三倍体14例、特纳综合征8例）孕11 - 13周时储存的胎儿头部三维超声容积。测量胎儿头部矢状面和横断面的蛛网膜下腔直径，并将每组非整倍体胎儿的蛛网膜下腔直径与双顶径（BPD）的关系与整倍体胎儿进行比较。随机选取20个头部容积，由两名不同的观察者记录所有测量值，以检查测量值之间的观察者间变异性。
在整倍体胎儿中，蛛网膜下腔的前后径、横径和矢状径随双顶径增加。三倍体和13 - 三体综合征中观察到的与预期的双顶径直径中位数显著增加，但21 - 三体综合征、18 - 三体综合征或特纳综合征中无显著变化。在三倍体中，92.9%（14例中的13例）的双顶径蛛网膜下腔直径高于整倍体胎儿的第95百分位数。所有三个蛛网膜下腔直径的组内可靠性或一致性都非常好。
孕11 - 13周的大多数三倍体胎儿表现出蛛网膜下腔直径增加。
