Abstracts

Rationale: Benign childhood epilepsy with centrotemporal spikes (BCECTS) is a localization-related, idiopathic epilepsy syndrome with benign evolution. Recent studies, however, have reported a higher incidence of neuropsychologic abnormalities including learning and behavioral dysfunctions in BCECTS although their neuroanatomical basis is not fully understood yet. The purpose of this study is to investigate the relationship between neuropsychological functions and structural changes of BCECTS. Methods: Fifteen children with benign childhood epilepsy with centrotemporal spikes (BCECTS) and sixteen healthy control subjects aged 6 to 17 were enrolled for this study (mean 11.66 3.18 year-old). All subjects were assessed by the Korean version Weschsler Intelligence Scale for Children (K-WISC III), frontal executive function test including Stroop and Trail-making test (TMT). Voxel-based morphometric (VBM) analysis was performed using SPM2 running in MATLAB 7.0. Images for volumetries were segmented into probabilistic maps of gray matter, white matter, and CSF with intensity nonuniformity. For statistical analysis, one-way ANOVA and Pearson s correlation coefficient were used. Results: Patients with BCECTS performed significantly worse than controls in several domains of the neuropsychological test: 105.09 16.12 vs. 112.67 12.62 for performance IQ, 101.09 8.68 vs. 114.00 13.63 for perceptual organization, 105.00 20.10 vs. 122.50 10.07 for attention, 87.36 10.28 vs. 105.50 16.90 for processing speed. Stroop and TMT showed longer response time and more frequent errors in patient group (p<0.001). VBM results revealed regional differences between BCECTS and control groups: most prominently, grey matter density of the bilateral prefrontal lobes (middle frontal gyri) decreased in BCECTS group compared with the control group (p<0.001). VBM analysis also demonstrated that TMT response time showed negative correlation with bilateral prefrontal (superior frontal gyri) grey matter densities in BCECTS group. Conclusions: Compared with controls, children with BCECTS exhibit a pattern of mild diffuse cognitive impairments, as well as significantly poor frontal executive functions. VBM and volumetric analysis in this study shows that BCECTS induced regional changes, which are possibly associated with altered brain functions in those patients. BCECTS might lead to neuroanatomical alterations in patients brains, which consequently affect their cognitive functions, especially in prefrontal and frontal regions.