Abstracts

Rationale: All pre-surgical functional mapping in pediatric epilepsy presents many practical difficulties and may require sedation especially in the case of very young children. But unlike somatosensory and motor mapping, laterality assessment and localization of receptive language presents additional theoretical challenges: it is debatable whether the cortical mechanisms of linguistic processing of speech stimuli are sufficiently activated under sedation to allow for hemispheric dominance determination. Methods: We addressed this issue using a consecutive series of 108 children assessed at the Le Bonheur Comprehensive Epilepsy Program of Le Bonheur Children s Hospital from January to December of 2012. Forty-nine children were assessed under sedation (age range 6 months 16 years) and 59 without sedation (age range 7 months 18 years) using our standard receptive language MEG protocol. Results: We were able to complete laterality assessment in approximately the same proportion of children and to obtain similar lateralization estimates in both groups, comparable to those that have been reported in the literature by our group and others, as shown in Table 1. Moreover, the reasons for unsuccessful assessment, listed in Table 2, were unrelated to sedation. Conclusions: The fact that the rates of successful laterality assessment in both groups are comparable suggests that such assessment can be performed under sedation using MEG. The rationale for the use and the reasons for the efficacy of the particular language protocol, even with very young children, will be discussed.