Abstracts

Rationale: Epilepsy often impairs intelligence, which may link with cortical abnormality of specific brain regions. This study aimed to investigate neuropsychological status and structural brain changes, and to characterize the relationship between each cognitive domain and specific brain areas in pediatric epilepsy patients. Methods: Twenty children and adolescents with epilepsy and sixteen healthy control subjects aged 6 to 17 were enrolled for this study (mean 12.3±3.8 years). All subjects were assessed by the Korean version Weschsler Intelligence Scale for Children (K-WISC III), Stroop and Trail-making test (TMT). Voxel-based morphometry (VBM) was used to compare the differences of gray matter (GM) and white matter (WM) density between patient and control groups.One-way ANOVA and Pearson’s correlation tests were used for statistical analysis. Results: Neuropsychological performance was significantly decreased in epilepsy patients compared with controls: 100.11±17.16 vs. 121.5±13.15 for total IQ (p=0.020), 101.42±15.54 vs. 117.33±7.44 for verbal IQ (p=0.026), and 98.58±10.94 vs. 112.67±12.62 for performance IQ (p= 0.030). Stroop and TMT showed longer response time and more frequent errors in patient group (p=0.005 and 0.002, respectively). VBM analyses showed decreased GM density in bilateral frontal cortex in epilepsy patients. In patient group, there was a positive correlation between the total IQ and bilateral frontal GM, between verbal IQ and left frontal GM, also between TMT scores and bilateral superior prefrontal GM densities. Conclusions: Epilepsy patients in childhood and adolescent age have lower intelligence and poorer performance in executive tests compared with healthy controls. Epilepsy might lead to neuroanatomical alterations in patients’ brains, which consequently affect their cognitive functions, especially in prefrontal and frontal regions.