Fetal Imaging Unit, FETALMED-Maternal-Fetal Diagnostic Center, Santiago, Chile.
Department of Obstetrics and Gynecology, Lennox Hill Hospital, Northwell Health, New York, New York.
Prenat Diagn. 2020 Apr;40(5):626-634. doi: 10.1002/pd.5667. Epub 2020 Mar 4.
To determine the key sonographic features for the diagnosis of sirenomelia in the first trimester of pregnancy.
Cases of sirenomelia from several prenatal diagnosis centers were retrospectively identified and reviewed. The diagnosis was established through the detection of fused lower limbs. Additional sonographic findings were also noted.
A total of 12 cases were collected. The most striking sonographic finding was the detection of malformed lower limbs, which appeared to be fused and in an atypical position. Nuchal translucency thickness was mildly increased in three cases (25%). An abdominal cyst, representing the dilated blind-ending bowel, was noted in seven cases (58%). Color flow imaging detected a single umbilical artery in six cases (50%) and the associated intra-abdominal vascular anomalies in three cases (25%). No cases of aneuploidy were detected. The pregnancy was terminated in nine cases (75%) and intrauterine demise occurred in the remaining three cases (25%).
The sonographic detection of abnormal lower limbs or an intra-abdominal cyst located laterally during the first-trimester scan may be warning signs of sirenomelia. This should prompt a detailed examination of the fetal lower body and intra-abdominal anatomy, including the main abdominal vessels, in order to look for additional confirmatory findings.
确定妊娠早期联体畸形的超声诊断要点。
回顾性分析了多家产前诊断中心的联体畸形病例。通过检测融合的下肢来确立诊断。还注意到了其他超声表现。
共收集了 12 例病例。最显著的超声表现是发现畸形的下肢，它们似乎融合在一起，位置异常。3 例（25%）胎儿颈项透明层厚度轻度增加。7 例（58%）病例中可见到一个腹部囊肿，代表扩张的盲端肠管。6 例（50%）病例中彩色血流成像检测到单脐动脉，3 例（25%）病例中检测到与宫内血管异常相关的血流。未发现非整倍体病例。9 例（75%）终止妊娠，其余 3 例（25%）胎儿宫内死亡。
在妊娠早期扫描中，若发现异常的下肢或位于腹部外侧的囊性结构，可能是联体畸形的预警信号。这应促使对胎儿下肢和腹部内脏解剖结构进行详细检查，包括主要腹部血管，以寻找其他确认性发现。
