第11~13周胎儿额上颌角的二维及三维超声测量

目的 比较及评价二维和三维超声在测量胎儿额上颌(FMF)角中的作用.方法 分别应用二维及三维超声方法在颜面正中矢状面测量11～13周正常胎儿的FMF角,比较两种测量方法所得测值的差异及可重复性,分析三维测量的FMF角与胎儿头臀长(CRL)的关系.结果 共37名胎儿测得FMF角.随CRL增大,测量例数增加,而FMF角减小.其中18名(48.65%)得到符合要求的二维测量平面,30名(81.08%)胎儿获得符合要求的三维重建平面.对同一胎儿,二维测量平面两次测值间的平均差异为2.78°±1.95°,明显大于三维重建平面两次测值间的平均差异(1.68°±1.01°,P<0.01).11名胎儿同时应用两种方法进行测量,所得FMF角差异无统计学意义.三维重建平面测得的FMF角随CRL的增加而减小,二者明显相关(r＝-0.540,P<0.01).结论 在 11～13周正常胎儿中,与二维超声相比,应用三维超声可以快速而精确地测量FMF角.

Investigation of frontomaxillary facial angle in fetuses at 11+0 to 13+6 weeks with two- and three-dimensional ultrasound

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.