Department of Obstetrics and Gynecology, Taipei City Hospital, Women and Children Campus, Taipei, Taiwan, ROC.
Prenat Diagn. 2013 Aug;33(8):711-5. doi: 10.1002/pd.4084. Epub 2013 May 1.
The aim of this research was to compare the fetal frontomaxillary facial (FMF) angle between normal and trisomy 21 fetuses at 11(+0) -13(+6) weeks gestation in a Chinese population.
A prospective observational study was performed that included 640 euploid and 45 trisomy 21 singleton pregnancies undergoing first trimester ultrasound screening between 11 and 13(+6) weeks of gestation. The FMF angle was measured in the midsagittal plane using the standard technique.
The fetal mean FMF angle decreased with the increasing crown-rump length (CRL) from 88.6°at a CRL of 45 mm to 78.5° at a CRL of 84 mm (FMF angle = 100.212 - 0.258 × CRL, R(2) = 0.222, p < 0.001). The overall mean FMF angle in the euploid population was 82.9° ± 4.1° and in trisomy 21 cases, 92.3° ± 5.2°.
Fetal FMF angle is affected by gestational age in a Chinese population, although it remains a significant predictor of fetal trisomy 21.
本研究旨在比较中国人群中 11（+0）-13（+6） 周正常和 21 三体胎儿的额眶面部（FMF）角。
这是一项前瞻性观察研究，纳入了 640 例正常二倍体和 45 例 21 三体单胎妊娠，这些孕妇均在妊娠 11-13（+6） 周行早期超声筛查。采用标准技术在正中矢状面测量 FMF 角。
胎儿的平均 FMF 角随头臀长（CRL）的增加而减小，从 45mm 的 CRL 时的 88.6°减小至 84mm 的 CRL 时的 78.5°（FMF 角=100.212-0.258×CRL，R²=0.222，p<0.001）。正常二倍体组的平均 FMF 角为 82.9°±4.1°，21 三体组为 92.3°±5.2°。
FMF 角在中国人中受孕周的影响，但它仍然是胎儿 21 三体的重要预测指标。
