Factors associated with lateralized cognitive dysfunction using the Cognitive Lateralization Rating Index in pediatric epilepsy.

Introduction: Optimizing cognitive outcomes of pediatric epilepsy surgery requires understanding of risk for change in function, typically based on hemispheric lateralization of language skills. Identification of cognitive lateralization in children is complicated by disease in the setting of ongoing functional development. A quantitative method for assessing lateralization, the Cognitive Lateralization Rating Index (CLRI), was used as a systematic way to assess lateralized cognitive dysfunction in a sample of pediatric epilepsy surgery candidates.

Method: The current study examined demographic and clinical variables in relation to the CLRI in 179 patients evaluated prior to epilepsy surgery from a national multi-site cohort.

Results: The sample was comprised of 179 patients (43.3% female; 76.3% White, 83.6% not Hispanic/Latino; age of seizure onset 6.58 years; seizure type: 84.7% focal; side of seizure onset: 51.3% left hemisphere, 38.1% right hemisphere). Results demonstrated that lateralization of cognitive dysfunction in a pediatric sample, as well as characterization of presumed atypical functional organization, is possible with the CLRI. There was no significant association of demographic variables on lateralization. Age of seizure onset was not significantly related to the CLRI. Children with focal epilepsy were more likely to have lateralized cognitive profiles than children with generalized seizures, though this relationship was not significant. Additionally, analyses demonstrated those with left hemisphere seizures were significantly more likely to have dominant hemisphere dysfunction or presumed atypical organization on the CLRI.

Conclusions: Results establish the CLRI as a potentially useful tool for both research and clinical care to quantitively stratify cognitive risk profiles for pediatric epilepsy surgery evaluations.