The antenatal diagnosis of migration disorders: a series of four cases

[Fetal MRI of pathological brain development]

Because of the superior tissue contrast, high spatial resolution, and multiplanar capabilities, fetal magnetic resonance imaging (MRI) can depict fetal brain pathologies with high accuracy. Pathological fetal brain development may result from malformations or acquired conditions. Differentiation of these etiologies is important with respect to managing the actual pregnancy or counseling future pregnancies. As a widened ventricular system is a common hallmark of both maldevelopment and acquired conditions, it may cause problems in the differential diagnosis. Fetal MRI can provide detailed morphological information, which allows refinement of the diagnosis of ventricular enlargement in a large number of cases. Systematic work-up of morphological details that may be recognized on MR images provides an approach for achieving a correct diagnosis in cases of ventricle enlargement.

Prenatal ultrasound detection of bilateral focal polymicrogyria

OBJECTIVES

Prenatal diagnosis by ultrasound of fetal polymicrogyria has been reported only once.

METHODS

We describe an additional case of polymicrogyria in a fetus from a monozygotic twin pair, probably the consequence of twin-to-twin transfusion syndrome.

RESULTS

On ultrasound, there were bilateral cortical hyperechogenic spots, and prenatal magnetic resonance imaging demonstrated the typical features of bilateral focal polymicrogyria.

CONCLUSION

Polymicrogyria can be considered in the differential diagnosis of hyperechogenic brain lesions on fetal ultrasound. We also confirm the risk of brain damage in monochorionic twins pregnancies and the likely hypoxic-ischemic etiology of polymicrogyria.