Mapping Metabolite and Neurotransmitter Alterations in Mesial Temporal Lobe Epilepsy Using Optimized Multi-TE MRSI: A Preliminary Study

Motivation: Multimodal imaging integrating molecular information promises to improve seizure foci lateralization and disease progression monitoring for mesial temporal lobe epilepsy (mTLE). Goal(s): To evaluate the feasibility of a multi-TE MRSI method optimized for simultaneously mapping metabolites and neurotransmitters in mTLE. Approach: Volumetric multi-TE MRSI and structural MRI data were acquired and analyzed for an mTLE cohort. Regional analysis was performed to quantified molecular maps and hippocampus volumetrics. Results: Reduced NAA/Cr ratios were observed for the ipsilateral hippocampous (epileptic side), consistent with prior findings and overall reduced hippocampus volumes. Reduced Glx/Cr ipsilaterally was observed. Interesting differences in anterior vs. posterior hippocampus were also reported. Impact: We demonstrated the feasibility of a new MRSI technique for mapping metabolic alterations in mTLE patients. Initial results support promise for improved lateralization and better understanding biochemical mechanisms of the disease using MRSI.