Functional language network connectivity in children of women with epilepsy with selective antenatal antiepileptic drug exposure

Purpose: Children of women with epilepsy and antenatal antiepileptic drug (AED) exposure have increased risk of language dysfunction. Our objective was to compare language related functional MRI network connectivity (FC) of children with women with epilepsy with antenatal AED exposure (CAED) with that of healthy children (COAED) for delineating functional basis of the language dysfunction. Methods: CAED under prospective follow up in Kerala Registry of Epilepsy and Pregnancy were consecutively sampled. COAED were identified from volunteers with normal brain MRI. Clinical Evaluation of Language Fundamentals score (CELF) was used to assess language. Functional MRI done using verb generation paradigm to activate language areas and key language network nodes were identified. A multivariate ROI-to-ROI and Seed-to-Voxel based FC was done using the selected seed regions in the language areas located in the right and left hemisphere in all subjects using the CONN functional connectivity toolbox in SPM8 under MATLAB. Results: Strong connectivity was observed within the identified language network between all language nodes bilaterally in CAED compare to controls. The mean connectivity strength of language network (LN) on the left side in CAED was 9.63 ± 4.62 (Mean ± SD) while for COAED it was 6.96 ± 3.67 (p=0.0001). The mean connectivity strength of LN between CAED (4.86 ± 1.07) and COAED (4.32 ±1.2) on the right hemisphere was not statistically significant (p=0.18). Conclusion: CAED with impaired language function had significantly increased functional connectivity which may indicate poor differentiation and localization of language centers.