Classic Case

Bilateral congenital perisylvian syndrome is a rare neurologic disorder characterized by intellectual disability, epilepsy, diplegia of the face, and pseudobulbar palsy. The syndrome is usually sporadic but can be autosomal recessive in rare cases. It is a form of malformations of cortical development, showing polymicrogyria over the bilateral opercular regions. The classic MR imaging findings are abnormally thick and excessive small gyri (polymicrogyria) in the perisylvian and insular cortices (A and C, white arrows). The opercula are open (B, arrows). Incidentally note absent septum pellucidum (C, yellow arrow).