From 2D to 5D the evolution of fetal neurosonography

Central nervous system (CNS) malformations are the most common defects in the human fetus and affect approximately 0.3-1% of live births1-2. Prenatal detection and accurate definition of CNS malformations are important since these anomalies frequently have a severe prognosis and are often associated with genetic syndromes2. Despite the high incidence of CNS anomalies and the clinical importance of their prenatal diagnosis, the efficacy of the screening program is still far from producing satisfactory results, especially when the study of the fetal head is limited to the axial brain planes3. An extended study of fetal CNS anatomy, including the addition of sagittal and coronal planes of the fetal brain, may help to improve the diagnostic efficacy4. Despite such evidence, the international guidelines for CNS anomalies screening suggest to limit the study to the three axial brain planes that allow to visualize falx, cavum septi pellucidum, thalami, lateral ventricles with the choroid plexus, cerebellum, and cisterna magna but do not permit the study of the corpus callosum, the cerebellar vermis, or other midline brain structures3. However, the identification of anomalies involving these structures is crucial since these anomalies are the most frequently associated with other malformations and chromosomal or genetic abnormalities2. “ 5D CNS simplifies the examination of a fetal brain and reduces inter-observer variability which helps to introduce coronal and sagittal planes in routine second trimester examinations, with the potential of improving the diagnostic efficacy of CNS anomalies. ” Article # WP201502-5D-CNS / Issue Date 5 Feb, 2015