A unilateral cleft lip patient with holoprosencephaly.

Holoprosencephaly includes a spectrum of conditions that have in common the associated anomalies of false median cleft lip, nasal malformation, orbital hypotelorism, and brain malformations. We recently encountered a patient with holoprosencephaly presenting with a rare unilateral cleft of the lip. This patient was potentially viable, although mental development was retarded.