Reversible operculum syndrome caused by progressive epilepsia partialis continua in a child with left hemimegalencephaly.

In a child with left hemimegalencephaly and seizures, a reversible operculum syndrome developed when continuous epileptic discharges spread from the left hemisphere to the contralateral central regions. The operculum syndrome lasted for three months until left hemispherectomy was performed. Soon after surgery the seizures and the operculum syndrome resolved. The operculum syndrome is a facio-pharyngo-glosso-masticatory diplegia usually due to structural lesions in both opercular regions. The reversibility of the syndrome in the reported case demonstrates that the operculum syndrome is sometimes functional rather than lesional.