Epileptic spasms in older pediatric patients: MEG and ictal high-frequency oscillations suggest focal-onset seizures in a subset of epileptic spasms.

摘要: Summary Objectives To elucidate the pathophysiology of intractable epileptic spasms in older children by describing interictal magnetoencephalography spike sources (MEGSSs), intracranial EEG ictal-onset zones (IOZs) and their ictal high-frequency oscillations (HFOs) surgical outcomes. Methods We studied five patients (4.5–14 years) who underwent surgery following video-EEG (VEEG) monitoring. analyzed clinical profiles, MRIs, scalp VEEGs, MEGSSs. localized HFOs using a sampling rate 1000 Hz multiple band frequency analysis (MBFA). Results Seizure onset ranged from 0.4 to 8 years. Three presented with asymmetrical spasms. Interictal VEEG recorded predominantly unilateral epileptiform discharges four; generalized multifocal one. Ictal showed high-amplitude slow waves superimposed fast four patients; hemispheric electrodecremental episodes MRI findings were normal three, polymicrogyria periventricular heterotopia one each. All had MEGSS clusters. HFOs, ranging 150 250 Hz, over Rolandic frontal regions four, also having extensive temporo-occipital HFOs. After cortical resection, three seizure free; >90% reduction frequency. One patient experienced residual seizures after resection HFO region. Conclusion Unilateral clusters MEGSSs overlapped regional IOZs High spatio-temporal MBFA before during revealed Seizure-free outcomes zone suggested that subset was focal-onset seizures.