The prenatal imaging of a rare congenital intracranial teratoma.

Fetal intracranial teratoma presents a rare and devastating diagnosis. Typically, this condition is first detected during routine prenatal ultrasounds, appearing as an irregular heterogeneous lesion. Further insights are gained through fetal magnetic resonance imaging (MRI), better characterizing the anomaly. The combination of these modalities provides detail-oriented high resolution MRI images, while follow-up ultrasounds capture dynamic growth changes, serving as a cost-effective and easily accessible adjunct. This fast-growing tumor leads to macrocephaly and ventriculomegaly, causing severe distortion of the brain parenchyma. Early detection is crucial for effective fetal management and preventing maternal complications. Unfortunately, treatment options are limited due to the tumor's aggressive nature, typically resulting in fetal demise shortly after birth. Here, we present the sonographic and MRI findings of a congenital intracranial teratoma, reaching massive proportions and replacing the entire cerebral hemisphere.

Prenatal diagnosis of zellweger syndrome by fetal MRI: a case report.

Zellweger Syndrome (ZS) is a rare peroxisomal disorder also referred to as cerebrohepatorenal syndrome. ZS is an autosomal recessive disease often manifesting in the neonatal period with profound dysfunction of the central nervous system, liver and kidneys. Prenatal diagnosis of this syndrome is infrequent with imaging findings on fetal MRI rarely illustrated in the literature. This case highlights the pivotal role fetal MRI can play in identifying subtle features of the disease that are difficult to visualize on prenatal ultrasound. It is important for pediatric radiologists to be familiar with the most common imaging features of ZS on fetal MRI to expedite the diagnosis and help facilitate appropriate prenatal counseling.

Prolonged hypoxia upregulates vascular endothelial growth factor messenger RNA expression in ovine fetal membranes and placenta.

OBJECTIVE: In ovine fetuses, 4 days of hypoxia resulted in a large increase in urine flow, without the development of polyhydramnios, which suggests that intramembranous absorption of the amniotic fluid was enhanced. Because vascular endothelial growth factor is speculated to be a regulator of intramembranous absorption through increases of membrane vascularity and fluid transport, we hypothesized that hypoxia upregulated vascular endothelial growth factor gene expression in the fetal membranes. STUDY DESIGN: Five near-term ovine fetuses that were subjected to 4 days of hypoxia and 5 age-matched time controls were studied. On day 4, the amnion, chorion, and placenta were collected for cellular localization and quantification of vascular endothelial growth factor messenger RNA and for the determination of vascular endothelial growth factor molecular forms that were expressed. The data were analyzed statistically with the use of t tests and 2-factor analyses of variance. RESULTS: Vascular endothelial growth factor messenger RNA was expressed in the fetal membranes localized to the amniotic epithelium and chorionic cytotrophoblast, and to the villous cytotrophoblast of the placenta. In hypoxic fetuses, vascular endothelial growth factor messenger RNA levels in these cell layers were significantly increased compared with the controls. Five vascular endothelial growth factor molecular forms were identified with vascular endothelial growth factor(164) being the most abundant form expressed. The pattern of expression of the forms was not altered by hypoxia. CONCLUSION: In the near-term ovine fetus, hypoxia induced vascular endothelial growth factor messenger RNA expression in the amnion, chorion, and placenta. This was associated with an increase in intramembranous absorption of amniotic fluid. We speculate that the increased intramembranous absorption was mediated by a vascular endothelial growth factor-induced increase in the transport of amniotic fluid into the fetal membranes.