Liu Wei, Qu Suhui, Wang Mujun, Xu Wanju, Zhang Guangying, Zhang Chengqi
Department of Ultrasound, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, 250014 Shandong China.
Department of Surgery, The First People's Hospital of Jinan City, Jinan, 250011 Shandong China.
Springerplus. 2016 Aug 11;5(1):1335. doi: 10.1186/s40064-016-2944-4. eCollection 2016.
The aim of this study was to observe whether there existed significant differences in the maxilla-nasion-mandible angle (MNM) between the first- and second-trimester of pregnancy, and to observe its predictive values for trisomy 18.
Two experienced ultrasonologists used 2D and 3D ultrasound imaging techniques to obtain the facial sagittal sections of fetuses in the first-trimester of pregnancy (crown-rump length 45-84 mm), respectively, so as to measure MNM.
MNM could be measured in 91 % of normal fetuses, and the measurement differences by different operators in different groups were <1.1°; average MNM was 11.0°, and no significant change was observed in different gestational ages (P = 0.15). The average of MNMs in fetuses with trisomy 18 was 16.6°, which were all higher than the 95th percentile of normal measurement data. The sensitivity and specificity of increased MNM on the abnormal detection of trisomy 18 were 54.7 and 97.4 %, respectively.
The feasibility and reproducibility of measuring MNM in early pregnancy were good. MNM had certain suggestive roles for aneusomic chromosomal abnormalities, especially for fetuses with trisomy 18.
本研究旨在观察妊娠早期与中期的上颌-鼻根-下颌角（MNM）是否存在显著差异，并观察其对18三体综合征的预测价值。
两名经验丰富的超声科医生分别使用二维和三维超声成像技术获取妊娠早期（头臀长45 - 84毫米）胎儿的面部矢状切面，以测量MNM。
91%的正常胎儿可测量MNM，不同组不同操作者的测量差异<1.1°；平均MNM为11.0°，不同孕周未见明显变化（P = 0.15）。18三体综合征胎儿的MNM平均值为16.6°，均高于正常测量数据的第95百分位数。MNM升高对18三体综合征异常检测的敏感性和特异性分别为54.7%和97.4%。
孕早期测量MNM的可行性和可重复性良好。MNM对染色体非整倍体异常，尤其是18三体综合征胎儿有一定的提示作用。
