Abstracts

Rationale: Lesion studies of the arcuate fasciculus (AC) indicate that this white matter pathway is a critical component of the linguistic network. It is also known that linguistic performance is often compromised in patients with non-lesional epilepsy. The goal of this diffusion tensor imaging (DTI) study was to explore the relation between the epilepsy, the functional integrity of the AC and the linguistic performance in the patients with non-lesional epilepsy. Methods: Twenty two epileptic patients with no apparent lesions on structural brain imaging (normal MRIs) underwent DTI analysis of the AC and neuropsychological testing. Results: The results show a high correlation between FA values in the left AC and some language and reasoning tasks (vocabulary, similarities and matrix reasoning). An analysis of variance was also carried out to check whether the FA values of the AC were affected in the hemisphere of seizure origin. The results showed that the patients had higher FA values in the left AC, regardless the origin of the seizure (left, right or both hemispheres). Conclusions: This study advances our understanding of how the epilepsy may affect the white matter pathways and the performance of the patients in neuropsychological tasks even in absence of evident brain injury.