VBM analysis of brain structures involved in the epileptogenic zone and clinical correlation with impulsivity and depression drug-resistant epilepsy

STIVALA E, KULSGAARD H, WOLFZUN C, SARUDIANSKY M, PRINCICH JP, GIAGANTE B, ODDO S, KOCHEN S, LARRABIDE I, D`ALESSIO L

Congreso; Reunión conjunta SAI-SAIC-AAFE-Nanomed; 2021

Sociedad Argentina de Investigación Clínica

Introduction: Impulsivity is a behavioral personality trait that may entail maladaptive social and personal consequences. Although several neuroimaging studies have investigated the structural correlates of impulsivity, the results remain highly inconsistent and heterogeneous.Objective: The aim of this work was to determine clinical features, impulsivity, and depression in patients with temporal and frontal epilepsy, and their correlation with brain anatomical structures by voxel-based morphometry (VBM - which analyzes the volume of cerebral gray matter) analysis. Methods: Patients with drug-resistant frontal (FLE) and temporal (TLE) epilepsy were included. The epileptogenic zone was confirmed by VEEG study. A complete neurological and psychiatric evaluation (SCID-I and -II, BDI-II, BIS-11, GAF) was performed in all patients. BIS-11 allows to divide impulsivity into three factors: Attentional, Motor and Nonplanning, aside of a Total impulsivity score. Brain images were analyzed with 3T MRI and epilepsy protocol (T2 coronal slices and 3-mm FLAIR). Two observers identified signal changes and loss of gray-white differentiation in the temporal pole ipsilateral to the epileptogenic zone. SPM12 and DARTEL were used for statistical analysis of VBM, from which the gray matter volume value (GMV), reference model creation, segmentation and normalization of the images emerged. Each patient was individually compared with the group of healthy subjects and a z-score value was established. Non-parametric tests (Mann Whitney and Spearman correlation) were performed, with a significance p-value of 0.05. Results: 36 patients with TLE and 7 patients with FLE (women, age) were included. No differences were found in the level of impulsivity and depression between both types of epilepsy (p> 0.05). GMV values were lower in the following structures: temporal amygdala, hippocampus, temporal pole, entorhinal cortex, and medial temporal gyrus ipsilateral to the epileptogenic zone in ELT; and in ipsilateral medial temporal gyrus in ELF.In ELT, higher levels of impulsivity correlated with higher GMV values in the ipsilateral entorhinal area (p