Epileptogenic zone diagnosis by means of deep electrical brain stimulation planned from electromagnetic simulations in a real head model. A case report

FERNANDEZ CORAZZA, MARIANO; C.H. MURAVCHIK; SANTIAGO COLLAVINI; J.P. PRINCICH; S. KOCHEN; S. ODDO; E. MAZZONI

Bangkok

Conferencia; 33rd International Epilepsy Congress (IEC 2019); 2019

ILAE

Deep electrical brain stimulation (DEBS) procedure was performed under the following characteristics. Electrode size diameter of 1,57 to 1,12 mm, contacts 1.57 to 2.41 mmlong, separated by 5 mm from one another. DEBS is applied between two adjacent leads of one electrode. Stimulation parameters: Bipolar 50Hz - 1mseg , T = 2 a 5 seg, Pulse widthand train frequency generally are kept constant throughout the whole stimulation procedure, intensity range from 1 to 10 mA, charge density (uC/cm2) from 12,34 to 123,38, untiltrigger after-discharges (AD), or clinical response. Cognitive tasks: hand tapping, naming, automatic speech (counting), reading and verbal fluency.We implemented a bipolar electrical stimulation procedure where the choice of injection electrodes was made by means of electromagnetic simulations to optimize thefocality of stimulation over an extensive lesion region with ZE hypothesis. The direct electromagnetic problem was simulated in a realistic head model. The model was madebased on the resonance of the subject. Using as stimulation threshold an electric field magnitude of 1 V / m, we analyze the focality of the volume of stimulation with respect tothe contacts of ZE and lesion.