First-trimester septated cystic hygroma and cavum velum interpositum cyst.

First-trimester septated cystic hygroma, frequently noted during general obstetric first-trimester screening, is strongly associated with fetal aneuploidy and structural anomalies and is considered an ominous finding. We present the case of a fetus with a first-trimester septated cystic hygroma and cavum velum interpositum cyst.