Abstracts

Rationale: Attention Deficit Hyperactivity Disorder (ADHD) in childhood epilepsy is associated with academic underachievement, neuropsychological impairment with deficits in executive function and psychomotor abilities, and a wide range of parent-reported dysexecutive behaviors (Jones et al., 2007). Prior VBM research has focused specifically on the frontal lobes. The purpose of this work is to compare the morphometric differences in whole brain anatomy between a healthy control population and pediatric epilepsy subjects with and without ADHD using voxel-based morphometry (VBM).Methods: 47 pediatric subjects with idiopathic epilepsy were selected with the following criteria: 1) diagnosis of epilepsy in the past 12 months, 2) chronological age between 8-18 years, 3) no developmental disabilities or neurological disorder, and 4) normal clinical MRI with no motion artifact. Within the subject population, 11 subjects met the DSM-IV definition of ADHD. 40 control subjects were age and gender-matched first-degree cousins.Results: When compared to controls and ADHD-negative epilepsy subjects, ADHD-positive subjects exhibited significant regions of increased gray and white matter volume relative to both the control and ADHD-negative populations in separate comparisons near the sensorimotor cortex and supplementary motor area as seen in Figure 1. The ADHD-positive group did not exhibit any volume decreases in gray or white matter with respect to either the control or ADHD-negative groups. Additionally, the ADHD-negative group did not exhibit any significant volume increases or decreases with respect to the control group.Conclusions: Prior VBM research in children with ADHD and epilepsy has focused specifically on the frontal lobes. This examination of whole brain VBM fails to reveal significant gray or white abnormalities outside the sensorimotor/frontal regions and also detects excess white matter in addition to previously reported excess in gray matter.