Lennox-Gastaut syndrome (LGS) is a severe epileptic encephalopathy characterized by multiple drug-resistant seizure types, bursts of diffuse slow spike-waves (1.5–2.5 Hz), and generalized paroxysmal fast activity (GPFA) on EEG, as well as intellectual disability.1 Despite diverse underlying etiologies, and regardless of the presence or absence of a brain lesion, the electroclinical phenotype of LGS is stereotypical, suggesting the involvement of a common epileptic brain network. Indeed, LGS has been conceptualized as a secondary network epilepsy, where the clinical and electrophysiologic manifestations reflect the activated network while often not revealing the specific initiating process or site.2 Imaging and electrophysiologic studies pointed to widely distributed network components residing in multilobar cortical regions, brainstem, and thalamus. The fact that surgical resection of a cortical lesion can alleviate seizures in some patients with LGS3 strongly supports the key role of cortex in LGS-associated epilepsy. However, conventional methodologies did not allow the identification of brain structures initiating epileptic activity, and the exact origin of LGS-related seizures remains enigmatic.

Source link