Metabolic and structural white matter integrity in drug-resistant temporal lobe epilepsy: A multimodal study using MRSI and DTI

Motivation: How axonal NAA changes in epilepsy and whether it is concordant with DTI metrics remains unclear. Goal(s): To investigate white matter metabolic and structural integrity using MRSI and DTI. Approach: Sixty-nine patients with drug-resistant TLE were recruited. WM NAA and fractional anisotropy (FA) were calculated for TLE and compared to healthy controls. Hippocampal NAA was used to predict integrity of its connected fibers. Results: NAA levels did not correlate with FA in white matter of TLE patients. While hippocampal NAA has direct effect on NAA of CGC and SS, amygdala was found to mediate fornix, SS and CGH. Impact: This work highlights NAA as an independent marker for white matter metabolic integrity of temporal lobe epilepsy patients in comparison to DTI-FA.