[Value of Fetal Frontomaxillary Facial Angle in Diagnosing Fetal Chromosomal Aneuploidy at 11+0 to 13+6 Weeks of Gestation].

OBJECTIVE: To determine the value of fetal Frontomaxillary facial angle (FMFA) in diagnosing chromosomal aneuploidy at 11+0-13+6 weeks of pregnancy. METHODS: Singleton pregnancies were randomly selected from January 2015 to August 2016 in our hospital. The crown-rump length (CRL), nuchal translucency (NT) and FMFA of the fetuses were measured and recorded, followed by chromosomal tests. FMFA and NT of the euploid fetuses were compared with those of the aneuploidy fetuses. A linear regression model was established between FMFA and CRL. The specificity and sensitivity of FMFA for diagnosing aneuploidy were assessed using the receiver operating characteristic (ROC) curve. RESULTS: The euploid fetuses had 80.61° (79.94°-81.28°) FMFA, compared with 91.24° (90.21°-92.25°) in the aneuploidy fetuses. The euploid fetuses had 1.63 mm (0.90-2.43 mm) NT, compared with 4.18 mm (3.12-5.44 mm) NT in the aneuploid fetuses. The differences were statistically significant (P<0.01). A negative correlation between CRL and FMFA was found in the euploid fetuses (y=-0.320 8x+100.32) . FMFA had a sensitivity of 90.5% and a specificity of 94.3% for diagnosing chromosomal aneuploidy with a cut-off value of 87.5° and 0.960 of the area under the curve. CONCLUSION: Aneuploid fetuses have significantly greater FMFA than euploid fetuses at 11+0 to 13+6 weeks of gestation.

Investigation of frontomaxillary facial angle in fetuses at 11+0 to 13+6 weeks with two- and three-dimensional ultrasound / 中国医学影像技术

Objective To investigate the role of two-dimensional ultrasound (2DUS) and three-dimensional ultrasonography (3DUS) in the measurement of fetal frontomaxillay facial (FMF) angle. Methods FMF angle in fetuses at 11~(+0) to 13~(+6) weeks were measured with 2DUS and 3DUS respectively. The difference between measurements and reproducibility were compared, and the relationship between FMF angle measured with 3DUS and crown-rump length (CRL) was assessed.Results FMF angle was obtained in 37 fetuses. Assessable fetuses increased with increased CRL, while the values of FMF angle decreased. Qualified 3D volumes were obtained from 30/37 (81.08%) fetuses, while qualified 2D measurements were available in 18/37 (48.65%) fetuses. For the same fetus, the difference between two measurements with 3DUS was significantly less than that with 2DUS (1.68°±1.01° vs 2.78°±1.95°, P<0.01). For the 11 fetuses assessed with both methods, the values of FMF angle obtained with two methods were not significant different. There was significant negative correlation between FMF angle and fetal CRL (r＝-0.540,P<0.01).Conclusion FMF angle in fetuses at 11~(+0) to 13~(+6) weeks can be achieved rapidly and accurately with 3DUS.