This syndrome is characterized by onset of refractory focal seizures in the first year of life, with associated severe encephalopathy. Focal seizures arise independently in both hemispheres and can migrate from one cortical region to another randomly but consecutively in the same seizure. Seizures are often prolonged with episodes of status epilepticus. Prognosis is poor with severe neurological disability and reduced life expectancy, although a milder evolution has been reported in a few children.