[Prenatal echographic diagnosis of iniencephaly. Apropos of a case].

Iniencephaly is a rare lethal malformation. It is associated with a defect in the occiput, alterations in the spinal column that are variable and retroflexion of the fetus. Antenatal diagnosis by ultrasound is possible because of the typical appearance: the fetal head is hyperextended, with distortion and shortening of the cervical spine. The occiput can be fused with lower vertebrae. Many associated malformations may be found: polyhydramnios, neurologic, facial and visceral abnormalities.