Microcephaly with Simplified Gyral Pattern Associated with Partial Rhombencephalosynapsis: A Case Report

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

• References

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