Proton MRS evaluation of inflammatory and drug refractoriness biomarkers in temporal lobe epilepsy.

Abstract

Temporal lobe epilepsy (TLE) is the most frequent type of focal epilepsies in adulthood and is often associated to an underlying lesion. Nearly 70% of TLE patients do not achieve seizure control using currently marked antiepileptic drugs (AED). It has been demonstrated both in human resected epileptic tissue and in animal models that epileptogenesis is a multifactorial process related to precipitant insults such as status epilepticus and also inflammatory events might be involved. Several studies using 1H-MRS as a tool have shown a relationship between trauma, viral infections, inflammatory CNS diseases and metabolic alterations, although such a parallel has not been yet demonstrated in human epilepsy. Moreover, glial and inflammatory alterations are possible mechanisms underlying refractoriness in TLE. Thus, our aim will be investigate a possible relationship between metabolic changes on 1H-MRS, inflammatory cytokines biomarkers and refractoriness in TLE. To address this issue, we propose three groups of study: 1 - patients with TLE who did not achieved satisfactory seizure control with the first AED trial (refractory group); 2 - patients who responded to the first AED trial (responsive group); 3 - control subjects (control group). Written informed consent will be taken from all subjects. After a regular T2 axial acquisition to define the region of interest, multivoxel 1H-MRS will be acquired using a PRESS ("Point Resolved Spectroscopy") sequence. Resonance intensities on MRS will be determined from integration of peak areas between frequency bounds using the software LC-Model. Then, the 1H-MRS metabolic profiles will be compared to each cytokine evaluated in the three referred groups.