Cyclopia: a radiological and anatomical craniofacial post mortem study.

Cyclopia is a rare foetal malformation characterized by a single palpebral fissure and a proboscis associated with severe brain malformation. Approximately 1.05 in 100,000 births including stillbirths are identified as cyclopian. Cyclopia is not compatible with life. The authors present an anatomical and histological study of the fronto-orbito-maxillary region carried out after 3-D CT reconstruction in a 21 week-old foetus with cyclopia. Anatomical and histological observations suggest that the integrity of the trigeminal nerves is very important for the normal development of the embryological structures of the face. Fusion of the facial processes in the midline takes place even if central prosencephalic structures are absent. For this reason the face in cyclopia, in both its positive and negative aspects, constitutes a model for the study of the normal development of this region.