Lennox–Gastaut syndrome

Lennox–Gastaut syndrome (LGS) is a difficult-to-treat form of childhood-onset epilepsy that most often appears between the second and sixth year of life. LGS is characterized by a triad of signs including frequent seizures of multiple types, an abnormal EEG pattern of less than 2.5 Hz slow spike wave activity, and moderate to severe intellectual impairment.