产前超声评估胎儿颜面轮廓及相关遗传学疾病

Prenatal ultrasound in diagnosis of fetal facial profile and associated genetic disorders

目的探讨产前超声评估胎儿颜面轮廓的可行性及对胎儿遗传学疾病的提示价值。方法应用产前二维及三维超声观察20胎胎儿的颜面正中矢状面,评估颜面轮廓异常,并与染色体分析结果进行对照。结果发现9胎21-三体、4胎18-三体、1胎13-三体和1胎4p-,5胎染色体正常。20胎中,鼻骨缺失或发育不良共8胎(6胎21-三体,2胎染色体正常);鼻前组织增厚9胎(8胎21-三体,1胎4p-);小下颌8胎(4胎18-三体,1胎21-三体,1胎13-三体,1胎4p-及1胎染色体正常);颜面扁平5胎(2胎21-三体,2胎Larsen综合征,1胎染色体正常);上颌前突2胎(1胎13-三体,1胎18-三体)。结论颜面正中矢状面有助于提示胎儿染色体异常及遗传综合征,其中鼻骨及下颌评估对21-三体及18-三体的提示意义明确,可作为中孕期筛查的常规内容。

Objective evaluate fetal facial profile with prenatal ultrasound, and to determine its diagnostic value for ge- netic disorders. Methods Sonographic findings of 20 fetuses were reviewed. Facial midsagittal plane was carefully evalua- ted with two-dimensional and three-dimensional ultrasound, and all fetuses underwent chromosomal analysis. Results There were 9 fetuses of trisomy 21, 4 of trisomy 18, 1 of trisomy 13 and 1 of 4p-, the remaining fetuses had normal kary- otype. Eight fetuses had absent or hypoplastic nasal bones, including 6 of trisomy 21 and 2 of normal karyotype. Nine fetu- ses showed increasing prenasal thickness, including 8 of trisomy 21 and 1 of 4p-. Eight fetuses had micrognathia, inclu- ding 4 of trisomy 18, 1 of trisomy 21, 1 of trisomy 13, 1 of 4p- and 1 of normal karyotype. Five fetuses showed flat face, two of which were trisomy 21, another two were Larsen syndrome, and the remaining 1 showed normal karyotype. Two fetuses had premaxillary protrusion, proved to be trisomy 13 and trisomy 18. Conclusion Facial midsagittal plane may contribute to prenatal detection of genetic disorders and need to be routinely examined during second-trimeter screening. Trisomy 21 and trisomy 18 should be especially noted when hypoplastic nasal bones or jaws are detected.