Middle interhemispheric variant of holoprosencephaly in an asymptomatic adult.

Middle interhemispheric variant of holoprosencephaly is an uncommon subtype of holoprosencephaly which is characterized by a midline connection of the two cerebral hemispheres in the posterior frontal and parietal regions with the separation of the anterior frontal and occipital lobes. It usually presents in early childhood with facial dysmorphism, seizures, motor dysfunction and mental-motor retardation. We herein present an unusual case of middle interhemispheric variant of holoprosencephaly which was asymptomatic and incidentally found in adulthood.