Resting State Connectivity Changes of Normal Brain Structures due to AED Modulation: An SEEG Study
Abstract number :
2.094
Submission category :
3. Neurophysiology / 3G. Computational Analysis & Modeling of EEG
Year :
2018
Submission ID :
501704
Source :
www.aesnet.org
Presentation date :
12/2/2018 4:04:48 PM
Published date :
Nov 5, 2018, 18:00 PM
Authors :
Irina Popa, Emergency University Hospital, University of Medicine and Pharmacy “Carol Davila”, Bucharest, Romania; Andrei Barborica, University of Bucharest, Romania FHC Inc.; Dragos Mihai Maliia, Emergency University Hospital, Bucharest, Ro
Rationale: Antiepileptic drugs (AEDs) are known to inhibit signal transport in the brain, reduce synchronous firing rate of neural populations and in this way might influence brain connectivity. AEDs’s mechanisms affect not only the epileptogenic structures but also normal brain structures. This study aims to determine if there is a significant change of connectivity of normal brain structures due to AED modulation using an SEEG approach. Methods: We selected patients with focal drug-resistant epilepsy from the Emergency University Hospital Bucharest that needed presurgical invasive evaluation by Stereo-EEG to localize the epileptogenic zone and tailor the resection. We further included only those patients that had their AEDs withdrawn during video-SEEG to record seizures. Two conditions of 1 minute each, were defined for each patient: A – full AED and B – no AED. For each condition we determined the mean degrees and strength of connections for sampled structures by means of the nonlinear regression analysis based on the h2 coefficient (Wendling, 2001) using AnyWave software (Colombet, 2015). We then compared the connectivity between the two conditions. Results: We included 4 patients that allowed us to analyse several brain regions: prefrontal mesial and lateral, temporal lateral, mesial and basal, primary and secondary motor and somatosensitive area, insular cortex and opercular cortex and the posterior cortex (Fig. 1, patient 2). There was a global significant decrease in connectivity degrees (33 out of 118 contacts) and strength (44 out of 118 contacts) in most of the structures located outside the epileptogenic zone when comparing AED condition with no AED condition (Wilcoxon nonparametric paired test and Bonferroni correction, p=0.001) Conclusions: AEDs have an inhibitory effect over neural populations and connectivity patterns in an acute set up with abrupt variation on AED. These findings might help us understand the impact of antiepileptic treatment on cognition Funding: Romanian UEFISCDI research grants PN-III-P4-ID-PCE-2016-0588, COFUND-FLAGERA II-SCALES and COFUND-FLAGERA II-CAUSALTOMICS, PN-III-P1-1.1-TE-2016-0706
