[Antenatal diagnosis of holoprosencephaly and its consequences. Apropos of 2 cases].

Cyclops represents the worst form of a rare malformation of the brain and face: holoprosencephaly. Two cases are reported, including one that was diagnosed at the 23rd week of pregnancy. Now, ultrasonography makes it possible to diagnose early; as soon as the 15th week of gestation. Ultrasound diagnosis is based on hypotelorism and anomalies of the mid-line, with or without facial abnormalities. The outcome is always poor. This malformation is associated with various conditions and a complete assessment, including the karyotype, morphologic studies of the fetus and of his family, and search for related minor facial dysmorphias (median labial or cleft palate with, with a single upper incisor) is mandatory. The condition recurs in 2 to 50% of cases depending on various associated conditions and on the family histories.