Decrease of global current source density predicts successful treatment in absence and juvenile myoclonic epilepsies

Abstract Objective To investigate relationship between treatment efficiency and EEG background activity changes in absence epilepsy (AE) and juvenile myoclonic epilepsy (JME) patients. Patients and methods EEGs of 31 patients were analysed before treatment and after six months of treatment. Three minutes of artifact-free waking EEG background activity (without epileptiform potentials) were analysed for each patient in both conditions. All the EEG samples were processed to LORETA (Low Resolution Electromagnetic Tomography). Average of all the voxel-wise current source density (CSD) values within the 0.5–8.0 Hz frequency range was computed for each EEG. Fischer's exact test was used to investigate association between the global CSD changes and the therapeutic outcome. Results Tight connection was demonstrated between seizure freedom and decreased CSD, and between persisting seizures and increased CSD (p  Significance An EEG-based biomarker that predicts successful drug treatment was described.