The Lennox-Gastaut syndrome is characterized by a triad of multiple seizure types, characteristic electroencephalogram (EEG) findings, and intellectual impairment.
Tonic-type seizures are most commonly seen in these patients.
Behavioral disturbances and cognitive decline are gradual-onset and last long after the first episode of epileptiform activity.
- is a typical childhood-onset, severe epileptic encephalopathy associated with a serious intellectual disability in 20%-60% patients at the time of the onset of seizures, the proportion of which will increase to 75%-95% at five years after the onset of seizures
- note that in some cases with normal intellect and behavior have also been reported
- specific electroencephalographic pattern varies from either bursts of slow spike-wave complexes or generalized paroxysmal fast activity
- slow spike-wave complexes (<2.5 Hz) are not considered to be pathognomonic for Lenox-Gastaut syndrome, but some experts have found generalized paroxysmal fast activity on electroencephalogram to be an essential criterion for diagnosing Lennox-Gastaut syndrome
Reference:
- Jahngir MU, Ahmad MQ, Jahangir M. Lennox-Gastaut Syndrome: In a Nutshell. Cureus. 2018 Aug 13;10(8):e3134. doi: 10.7759/cureus.3134.