Sepulveda Waldo
Fetal Medicine Center, Clinica Las Condes, Casilla 208, Santiago 20, Chile.
J Ultrasound Med. 2009 Aug;28(8):1077-80. doi: 10.7863/jum.2009.28.8.1077.
The purpose of this series is to describe the first-trimester sonographic findings leading to the diagnosis of monosomy 18p.
The sonographic appearance of 2 cases of monosomy 18p, detected as part of first-trimester sonographic screening for aneuploidy at this institution, was reviewed.
Increased nuchal translucency thickness, alobar holoprosencephaly, and facial defects were detected in both cases. Chromosomal analysis by chorionic villus sampling revealed de novo del(18p) in 1 case and monosomy 18p as the result of an 18q isochromosome in the other.
Increased nuchal translucency thickness in association with brain and face anomalies on a first-trimester scan allowed the early diagnosis of monosomy 18p. Fetuses with holoprosencephaly can be readily identified in the first trimester by examining a cross section of the fetal head looking for the "butterfly" sign. Prenatal karyotyping provides important information regarding the etiology and risk of recurrence in these cases.
本系列研究旨在描述孕早期超声检查发现导致18p单体综合征诊断的相关表现。
回顾了在本机构作为孕早期非整倍体超声筛查一部分而检测出的2例18p单体综合征的超声表现。
2例均检测出颈项透明层厚度增加、无脑叶型前脑无裂畸形和面部缺陷。经绒毛取样进行染色体分析，1例显示为新发18p缺失，另1例则是由于18号染色体等臂染色体导致的18p单体综合征。
孕早期超声扫描时颈项透明层厚度增加并伴有脑和面部异常，有助于早期诊断18p单体综合征。通过检查胎儿头部横断面寻找“蝴蝶”征，可在孕早期轻松识别前脑无裂畸形胎儿。产前核型分析为这些病例的病因及复发风险提供了重要信息。
