Related Experiment Video
Updated: Aug 30, 2026

Generation and On-Demand Initiation of Acute Ictal Activity in Rodent and Human Tissue
Published on: January 19, 2019
Idiopathic generalized epilepsy: biases and inconsistencies
Gabriella Foca1, Rajiv Potluri1, Juliana Laze1
1NYU Grossman School of Medicine, USA.
Objectives:
Distinguishing Idiopathic Generalized Epilepsy (IGE) from focal epilepsy (FE) can be challenging when IGE cases present with asymmetric clinical or electroencephalographic (i.e., atypical) features. We aimed to identify factors that lead to discordance in IGE diagnoses among epileptologists.
Methods:
41 patients with IGE and 6 patients with FE or mixed focal and generalized epilepsy followed at the NYU Comprehensive Epilepsy Center for ≥5 years were identified. IGE cases included typical (n = 18) and atypical (n = 23) presentations. Anonymized summaries of patients at initial presentation and 5-year follow-up were presented in random order to epileptologists who categorized them as generalized epilepsy (GE), FE, or other. Factors leading to discordance were identified.
Results:
Inter-rater agreement was moderate for atypical IGE cases at initial presentation (AC1 = 0.54, 95% CI 0.31-0.77, p < 0.01) and 5-year follow-up (AC1 = 0.48, 95% CI 0.25-0.72, p < 0.01). For atypical cases, asymmetric epileptiform activity was most commonly associated with increased discordance.
Discussion:
Epileptologists may underdiagnose IGE when patients have asymmetric EEG or clinical features. Review of one time point (i.e., vignettes) may mask the diversity of features that may support a localized epilepsy when serial reviews reveal a generalized epilepsy.
Related Concept Videos
Epilepsy ll: Types
Epilepsy and Seizures: Overview
Various factors can trigger epilepsy, including genetic factors, brain damage, metabolic causes, and unknown etiology. Diagnosis of epilepsy involves electroencephalography (EEG), which...
Seizures: Classification
Seizures are typically classified into two main categories: focal and generalized seizures.
Focal Seizures
Focal seizures originate from specific regions of the brain. These seizures are further sub-classified into two types:
Seizures l: Introduction
Seizures ll: Types
Encephalitis l: Introduction

