Further insights into unusual acrania-exencephaly-anencephaly sequence caused by amniotic band – first trimester fetoscopic correlation with two- and three-dimensional ultrasound

Abstract Objectives Antenatal detection of acrania-exencephaly-anencephaly (AEA) sequence beyond 10 completed weeks of gestation is usually straight-forward. An earlier detection and classification of the causative conditions prior to disaggregation of exposed dysplastic brain tissue remains challenging. Case presentation We present two- and three-dimensional ultrasound correlated with fetoscopic findings of an unusual type of neural tube defect at 11 gestational weeks caused by an amniotic constriction ring resulting in cystic degeneration of the developing skull. Conclusions By giving further illustrative insights into early defective brain development, this report confirms recent findings of an unusual subtype of acrania-exencephaly-anencephaly sequence suggesting early disruption of the developing brain, following an amniotic entrapment of the skull.