[Ultrasound scan of the fetal thymus]. / Evaluación ecográfica del timo fetal.

There is an increased interest nowadays on ultrasound analysis of the fetal thymus. Abnormal fetal thymic growth have been associated with DiGeorge syndrome, conotruncal cardiac malformations, chromosomal abnormalities and adverse outcome in different perinatal conditions as intrauterine growth restriction, preterm birth and others. Different methodologies that measure the fetal thymus by ultrasound have been published, however there is not a consensus of which one is the most useful. Our aim is to describe these methodologies and discuss their clinical applications.

[Perinatal outcome after prenatal diagnosis of intra-abdominal umbilical vein varix]. / Resultados perinatales luego del diagnóstico ecográfico prenatal de variz de la vena umbilical intra-abdominal.

BACKGROUND: Progress in echographic techniques, particularly, high-resolution echography and color Doppler, as well the higher deep on knowledge and systematization in fetal anatomy exploration, are the main responsible of the increased number of cardiovascular anomalies diagnosed prenatally. OBJECTIVE: To describe the sonographic findings and perinatal outcomes in cases with prenatal ultrasound diagnosis of intra-abdominal umbilical vein varix. MATERIAL AND METHODS: A descriptive and retrospective study of cases with prenatal ultrasound diagnosis of umbilical vein varix. The diagnosis is performed at the level of the abdominal circumference when the diameter of the vessel is above the established parameters for a certain gestational age. Variables concerning maternal-fetal features, ultrasound findings and perinatal outcomes of affected cases are described. RESULTS: From August 2008 to August 2012 14 cases of intraabdominal umbilical vein varix were diagnosed in our center with a mean gestational age at diagnosis of 29 weeks. Of the 14 cases, 35% had associated anomalies, mostly cardiovascular anomalies. No chromosomal defects were detected. Perinatal outcomes in newborns were favorable, with mean gestational age at delivery of 38 weeks. Only one case of monochorionic-monoamniotic twin pregnancy required preterm elective termination secondary to a twin-to-twin transfusion syndrome. CONCLUSION: Prenatal diagnosis of intra-abdominal umbilical vein varix should be followed by further studies given its possible association with other anomalies, chromosomal defects and cases of stillbirth. However, isolated cases of umbilical vein varix, representing a majority, often evolve favorably with few complications.