The diagnostic utility of intracranial EEG monitoring for epilepsy surgery in children

Objective There are limited data on the indications for the use of chronic invasive electroencephalography (EEG) monitoring (IEM) for pediatric epilepsy surgery. Methods We retrospectively studied 102 children who underwent intracranial monitoring to map critical cortex, localize the epileptogenic region, or resolve divergent findings. We assessed IEM utility based on changes to the resection plan following analysis of noninvasive data. Results IEM was judged useful in 87% of cases and had greatest utility for resolving discordant data and localizing extratemporal and multilobar epileptogenic zones. IEM data were least useful for seizure onset in the temporal lobe and had little utility for direct cortical stimulation mapping unless functional magnetic resonance imaging (fMRI) revealed atypical language representation or the epileptogenic zone was in proximity to critical cortex. Significance IEM utility was demonstrated for a majority of cases with well-defined indications. The method of assessing utility will facilitate multicentric studies toward developing future consensus and practice guidelines.