Abstract
Congenital microcephaly with simplified gyral pattern has been well documented in
the literature. It is characterized by a head circumference of less than two standard
deviations for age associated with abnormal sulcation. In its mild presentation, this
entity is usually described as an isolated anomaly. It presumably results from a brain
insult associated with hypoxic–ischemic damage, intracranial infection, or metabolic
disease. Rhombencephalosynapsis is a rare condition usually consisting of vermian
agenesis or severe hypogenesis, fusion of the cerebellar hemispheres, and apposition
or fusion of the dentate nuclei. There are several recent studies focusing on each
one of those entities individually, but they do not show any correlation/association
between the two of them. This is a case report of an 8-year-old child with neurodevelopmental
delay who had episodes of seizures up to 3 years of age. An MRI scan showed marked
craniofacial disproportion with dominance of the face over the skull, simplified gyral
pattern associated with hypogenesis of the cerebellar vermis, and communication of
the folia in the posterior segments of the cerebellar hemispheres. In this case report,
we will briefly discuss cerebellar embryology and the process of cortical differentiation,
as well as possible associations between rhombencephalosynapsis and other brain abnormalities.
Keywords
rhombencephalosynapsis - simplified gyral pattern - microcephaly
