The Hepatic Fetal Venous System

The vascular architecture of the human liver is established at the end of the 10th week of gestation as a result of a complex process. Recent developments in ultrasonographic imaging facilitate the prenatal evaluation of this system. However, many of the involved mechanisms are poorly understood. The hepatic primordium is in contact with the vitelline veins and the umbilical veins, and by the end of the 6th week, the afferent venous system of the liver is acquired giving rise to the portal vein, the portal sinus, and the ductus venosus. The only afferent vein of the liver that remains open at birth is the portal vein. Also, the efferent venous system of the liver is formed and emerges from the vitelline veins

Ductus Venosus Agenesis and Portal System Anomalies—Association and Outcome

To evaluate the prenatal diagnosis of agenesis of ductus venosus (ADV) and portal venous system (PVS) anomalies and describe the outcome of these cases, either isolated or associated. We evaluated the intrahepatic vascular system regarding the presence of normal umbilical drainage and PVS characteristics in the second and third trimester of pregnancy. The associated anomalies and umbilical venous drainage were noted. Follow-up was performed at six months follow-up. Ultrasonography was performed in 3517 cases. A total of 19 cases were prenatally diagnosed: 18 ADV cases, seven abnormal PVS cases, and six associations of the two anomalies. We noted an incidence of 5.1‰ and 1.9‰ for ADV and PVS anomalies, respectively. Out of the 18 ADV cases, 27.7% were isolated. Five cases (26.3%) presented genetic anomalies. PVS anomalies were found in 33.3% of the ADV cases. ADV was present in 85.7% of the PVS anomalies. DV and PVS abnormalities were found with a higher than reported frequency. Normal DV is involved in the normal development of the PVS. Additional fetal anomalies are the best predictor for the outcome of ADV cases. Evaluation of PVS represents a powerful predictor for ADV cases and addresses the long-term prognosis

First Trimester Ultrasound Detection of Fetal Central Nervous System Anomalies

Objective: To evaluate the potential of the first-trimester ultrasound (US) features for the detection of central nervous system (CNS) anomalies. Methods/Methodology: This is a prospective one-center three-year study. Unselected singleton pregnant women were examined using an extended first-trimester anomaly scan (FTAS) that included the CNS assessment: the calvaria shape, the septum (falx cerebri), the aspect of the lateral ventricles, the presence of the third ventricle and aqueduct of Sylvius (AS) and the posterior brain morphometry: the fourth ventricle, namely intracranial translucency (IT), brain stem/brain stem–occipital bone ratio (BS/BSOB) and cisterna magna (CM). The spine and underlying skin were also evaluated. The cases were also followed during the second and third trimesters of pregnancy and at delivery. FTAS efficiency to detect major CNS abnormalities was calculated. Results: We detected 17 cases with CNS major abnormalities in a population of 1943 first-trimester (FT) fetuses, including spina bifida with myelomeningocele, exencephaly-anencephaly, holoprosencephaly, hydrocephaly, cephalocele and Dandy-Walker malformation. The CNS features in the abnormal group are presented. In the second trimester (ST), we further diagnosed cases of corpus callosum agenesis, cerebellar hypoplasia, vein of Galen aneurysm and fetal infection features (ventriculomegaly, intraventricular bands, intraventricular cyst and hyperechoic foci), all declared normal at the FTAS. During the third trimester (TT) scan we identified a massive fetal cerebral haemorrhage absent at previous investigations. We report a detection rate of 72.7% of fetal brain anomalies in the FT using the proposed CNS parameters. The sensitivity of the examination protocol was 72.7%, and the specificity was 100%. Conclusion: A detailed FT CNS scan is feasible and efficient. The majority of cases of major CNS abnormalities can be detected early in pregnancy. The visualization rates of the CNS parameters in the FT are great with short, if any, additional investigation time. FT cerebral disorders such as haemorrhage or infections were missed in the FT even when an extended evaluation protocol was used