Typical lesions in the fetal nervous system: correlations between fetal magnetic resonance imaging and obstetric ultrasonography findings

Central nervous system (CNS) malformations play a role in all fetal malformations. Ultrasonography (US) is the best screening method for identifying fetal CNS malformations. A good echographic study depends on several factors, such as positioning, fetal mobility and growth, the volume of amniotic fluid, the position of the placenta, the maternal wall, the quality of the apparatus, and the sonographer’s experience. Although US is the modality of choice for routine prenatal follow-up because of its low cost, wide availability, safety, good sensitivity, and real-time capability, magnetic resonance imaging (MRI) is promising for the morphological evaluation of fetuses that otherwise would not be appropriately evaluated using US. The aim of this article is to present correlations of fetal MRI findings with US findings for the major CNS malformations.

Fetal neuroblastoma: ultrasonography and magnetic resonance imaging findings in the prenatal and postnatal IV-S stage

We report a case of a fetus with an ultrasonography diagnosis of a neuroblastoma during a routine third trimester fetal scan, which presented as a hyperechogenic nodule located above the right kidney. No other abnormalities were found in the ultrasonography scan; however, the follow-up ultrasonography during the 36th week of gestation revealed that the lesion had doubled in size. At the same time, magnetic resonance imaging demonstrated a round mass in the topography of the right adrenal gland with a low signal on T1-weighted images and slightly high signal on T2-weighted images, causing a slight inferior displacement of the kidney. The liver had enlarged and had heterogeneous signal intensity, predominantly hypointense on T2-weighted sequences. Based on these findings, a diagnosis of congenital adrenal neuroblastoma with liver metastases was suggested. A newborn male was delivered by cesarean section 2 weeks later. The physical examination of the neonate revealed abdominal distention and hepatomegaly. The infant had a clinical follow-up in which no surgical or medical intervention was required. At 5 months of age, the infant was asymptomatic with a normal physical examination.

Fetal neuroblastoma: ultrasonography and magnetic resonance imaging findings in the prenatal and postnatal IV-S stage

We report a case of a fetus with an ultrasonography diagnosis of a neuroblastoma during a routine third trimester fetal scan, which presented as a hyperechogenic nodule located above the right kidney. No other abnormalities were found in the ultrasonography scan; however, the follow-up ultrasonography during the 36th week of gestation revealed that the lesion had doubled in size. At the same time, magnetic resonance imaging demonstrated a round mass in the topography of the right adrenal gland with a low signal on T1-weighted images and slightly high signal on T2-weighted images, causing a slight inferior displacement of the kidney. The liver had enlarged and had heterogeneous signal intensity, predominantly hypointense on T2-weighted sequences. Based on these findings, a diagnosis of congenital adrenal neuroblastoma with liver metastases was suggested. A newborn male was delivered by cesarean section 2 weeks later. The physical examination of the neonate revealed abdominal distention and hepatomegaly. The infant had a clinical follow-up in which no surgical or medical intervention was required. At 5 months of age, the infant was asymptomatic with a normal physical examination.