Summary Epilepsy surgery is highly successful in achieving seizure freedom in carefully selected children with drug‐resistant focal epilepsy. Advances in technology have aided presurgical evaluation and increased the number of possible candidates. Many of the tests employed are resource intense, and in specific cases they may be unhelpful or have adverse effects. Some standardization of the evaluation process is thus considered timely. Given the lack of class 1 or 2 evidence defining the relative utility of each test in specific clinicopathologic cohorts, a set of expert recommendations was attempted using consensus among members of the Pediatric Epilepsy Surgery Task Force of the International League Against Epilepsy (ILAE) Commissions of Pediatrics and Diagnostics These recommendations aim to limit fringe over or underutilization of use while retaining substantial flexibility in the use of various tests, in keeping with most standard practices at established pediatric epilepsy centers. A PowerPoint slide summarizing this article is available for download in the Supporting Information section http://onlinelibrary.wiley.com/doi/10.1111/epi.12544/suppinfo.

Objective We sought to identify genetic causes of early onset epileptic encephalopathies with burst suppression (Ohtahara syndrome and early myoclonic encephalopathy) and evaluate genotype-phenotype correlations. Methods We enrolled 33 patients with a referral diagnosis of Ohtahara syndrome or early myoclonic encephalopathy without malformations of cortical development. We performed detailed phenotypic assessment including seizure presentation, EEG, and MRI. We confirmed burst suppression in 28 out of 33 patients. Research-based exome sequencing was performed for patients without a previously identified molecular diagnosis from clinical evaluation or research-based epilepsy gene panel. Results In 17/28 (61%) patients with confirmed early burst suppression, we identified variants predicted to be pathogenic in KCNQ2 (n=10), STXBP1 (n=2), SCN2A (n=2), PNPO (n=1), PIGA (n=1), and SEPSECS (n=1). In 3/5 (60%) patients without confirmed early burst suppression, we identified variants predicted to be pathogenic in STXBP1 (n=2) and SCN2A (n=1). The patient with the homozygous PNPO variant had a low CSF pyridoxal-5-phosphate level. Otherwise, no early laboratory or clinical features distinguished the cases associated with pathogenic variants in specific genes from each other or from those with no prior genetic cause identified. Interpretation We characterize the genetic landscape of epileptic encephalopathy with burst suppression, without brain malformations, and demonstrate feasibility of genetic diagnosis with clinically available testing in over 60% of our cohort with KCNQ2 implicated in one third. This electroclinical syndrome is associated with pathogenic variation in SEPSECS.

Dexmedetomidine sedation elicited an EEG pattern similar to that of Stage II sleep with modest increases in theta, alpha, and beta activity. Dexmedetomidine does not hinder interpretation of the EEG, suggesting that it may be a uniquely useful agent for EEG sedation in children.

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